Final Report Summary - PHOTOMEM (Photocatalytic and membrane technology process for olive oil mill waste water treatment)
Executive summary:
Olives undergo a series of treatments and operations in order to reach the point at which oil is extracted from them. One of the last steps in olive oil production is the purification and final separation of the olive oil from the residual pulp and an aqueous suspension, called olive mill wastewater (OMWW). The water present in the OMWW is partially added during the process, in major extent in the three phase process. This waste water stream is a strong pollutant because of its high organic load and phytototoxic, due to the presence of antibacterial phenolic substances, resistant to biological degradation. The discharge of OMWW is not allowed trough the municipal sewage system and/or natural effluents. Unfortunately, the available technologies for the wastewater treatment are too complicated to be operated in a mill factory environment and very expensive for to the olive oil business. Aim of the PHOTOMEM project is therefore to define and implement a process for the treatment of wastewater derived from agro-food processing, in particular olive mill wastewater (OMWW) waste water.
Project Context and Objectives:
Mediterranean countries are strongly affected by the serious environmental problem related to the disposal of the olive oil mills wastewater, since they produce 95% of the worldwide olive-oil. In these countries about 11 million tons of olives are produced per year from which around 1.7 million tons of olive oil are extracted. The seasonal polluting load of olive-oil production in these countries is equivalent to the one of 22 million people, since the in average COD value of OM http://www is about 80 g l-1 and its volume is about 0.8 ton per ton of olive. Moreover, this huge amount of polluted wastewater is produced only during 2-3 months per year (average duration of the olive oil campaign), making the storage difficult and entailing the need of an immediate treatment to eliminate its environmental hazard.
As already mentioned, the discharge of OM http://www is not allowed trough the municipal sewage system and/or natural effluents. At the same time, however, no efficient and low-cost treatment exists for the treatment of such effluents to be performed in an industrial environment such as the mill factory one. For this reason, the current disposal systems adopted, which in most of the cases infringe the European and national regulations, are:
- Evaporation: the OMWW and the alpechin are stored in huge tanks or in evaporation ponds and the water is evaporated by sun throughout the year. The main problem are: the storage needs huge tanks, the evaporation leads to bad smelling air and must be performed far away from towns; also, a pollutant rich solid residue is generated and must be disposed.
- Disposal on terrains: the legislation allows disposing OMWW on compatible and suitable terrains (which are relatively rare and need to be toughly monitored) and within certain limits (50-80 m3/ha/y). The available terrains are not sufficient when compared to the quantities produced yearly by an average olive mill factory (20-50 m3/d). The problems caused by this procedure are pollution of the groundwater layers and of the terrains. For this reason, the procedure is considered illegal according to the EU Directive 91/271/EEC on urban waste-water treatment.
Specific activities were carried out in order to obtain the above mentioned goals:
First Reporting Period
- The identification of the characteristics of PHOTOMEM target wastewaters, in terms of the organic matter contents, for the definition of the WW treatment to be applied,
- The definition of the optimal lab procedure for the production of magnetic nanocores and for their coating with silica and titania, based on the comparison between different processes,
- A preliminary evaluation of the photocatalytic process efficiency and the identification of the optimal catalyst for PHOTOMEM reactor,
- The determination of the process for polyphenols recovery and relative adsorption tests, and assembly of all these stages for building up the final WW treatment process.
Second Reporting Period
- The definition of the optimal lab procedure for the production of magnetic nanocores and for their coating with silica and titania, based on the comparison between different processes,
- The subsequent optimization of the production process so as to be able to produce high quantities of nanoparticles for the PHOTOMEM process,
- The determination of the process for polyphenols recovery and relative adsorption tests, and the sizing of an adsorption column to be used after the nanofiltration stage for recovering polyphenols from the treated wastewater,
- The selection of an optimized shape for the photoreactor allowing the scale up to industrially treated volumes of OMWW, obtained by testing different reactor configurations on lab scale prototypes and assessing their performances,
- The final 3D CAD design of the chosen photoreactor including the magnetic trap for the recovery of the nanoparticles used during the photocatalytic step,
- The implementation of the pilot plant, including automation and control
- The realization of beta tests and of a session of tests on fresh OMWW collected in November for the final assessment of the organics removal performed via the PHOTOMEM process.
The main technical outputs of the project were:
- The definition of the PHOTOMEM requirements
- The system specifications and layout
- A detailed report on the produced ferromagnetic nanoparticles characteristics and on their properties
- First results on adsorption and polyphenols recovery tests
- The WW treatment process design
- The realisation of a website dedicated to the project
- A detailed report on the produced ferromagnetic nanoparticles characteristics and on the production process performed by ARMINES in collaboration with MT, with an evaluation of the production costs for the future exploitation of the technology,
- the selection of the air lift configuration for the photoreactor, and its concept and executive design based on hydraulic and photocatalytic tests carried out at lab scale
- the Process and Instrumentation Scheme for the PHOTOMEM plant
- a pilot plant for the treatment of 1 m3/day of OMWW was implemented and tested
- The sizing of the adsorption column by which the recovery of polyphenols was possible in the PHOTOMEM process,
- The results of the tests on the pilot plant, allowing an estimation of the market potential of the PHOTOMEM technology,
On the dissemination and exploitation side, the main goals achieved in the reference period were:
- The estimation of nanoparticles production costs at an industrial scale,
- The implementation of specific dissemination activities having the purpose of spreading the results of the project to an audience as wide as possible,
- The assessment of the impact that the PHOTOMEM technology might have on the market once exploited by the SMEs and the realization of an exploitation strategy for the process and the plant commercialization.
- The update of the project website
The project activities can be thought as structured in 2 main phases:
- Phase 1: the setup of the system specifications and architecture and the preliminary tests on the photocatalytic process, the trials on the nanoparticles production for the identification of the best recipe, and the studies on the polyphenols recovery process (RP1);
- Phase 2: the outline of the process final design, the implementation of the different steps of the process on the PHOTOMEM pilot plant, and the field tests on OMWW with subsequent assessment of the technology performances (partially performed in RP1 and continued in RP2).
The specific objectives of each of the ongoing Work Packages in the whole project, according to the Description of Work, were:
WP1 Specifications and Layout
- Definition of the expected requirements for the WW treatment for the industrial application, expected performances, costs, etc.
- Definition of the technical specifications and draft of the process layout
- Definition of the expected performance of the photocatalytic nanoparticles production process and cost
Expected deliverables:
- D1: PHOTOMEM Requirements (Responsible partner: BIOAZUL - Report M1)
- D2: PHOTOMEM Specifications and Layout (Responsible Partner: UNIRO - Report M3)
WP2 Photocatalytic Nanoparticles Production Process.
This WP was devoted to perform the coating the ferromagnetic nanoparticles with sol gel silica and nanotitania, to carry out the optimisation of nanoparticles production in relation to photocatalytic performance, magnetic recovery, cost, etc., and to finally define an industrially scalable production process for the nanoparticles. Expected deliverables:
- D4: Ferromagnetic photocatalytic nanoparticles characteristics (Responsible partner: ARMINES Report M9)
- D8: Operative conditions for optimal production of ferromagnetic photocatalytic nanoparticles (Responsible partner: ARMINES Report - M12)
- D16: Layout and analysis of scalable production process for ferromagnetic photocatalytic nanoparticles (Responsible partner: ARMINES - Report - M18)
WP3 Development of photocatalytic process and reactor.
WP3 was intended to perform the definition and implementation of a lab setup of photoreactor for the photocatalytic reaction, to make tests on nanoparticles in the reactor and evaluate the COD content removal efficiency and recovery capacity, and, finally, to define the photoreactor design for the PHOTOMEM pilot plant. Expected deliverables:
- D5: Preliminary results of photocatalytic tests (Responsible partner: TUC Report M9)
- D9: Results of photocatalytic tests (Responsible partner: TUC - Report M12)
- D10: Photoreactor concept design (Responsible partner: TUC Report M12)
WP4 - Development of the polyphenols recovery.
This WP was aimed at performing an experimental investigation on the polyphenols adsorption-desorption process, at investigating the feasibility of the polyphenols recovery and at designing the adsorption recovery unit. Expected deliverables:
- D6: Preliminary results of the adsorption tests (Responsible partner: UNIRO Report M9)
- D11: Results of the adsorption tests (Responsible partner: UNIRO Report M12)
- D13: Polyphenols recovery unit design (Responsible partner: UNIRO Report M15)
WP5- WW treatment process design.
This WP had its main goals in the design of a pilot scale photoreactor with a recovery system for nanocatalyst, and in the design of a complete WW treatment pilot plant, integrating the photoreactor with membrane filtration steps. Expected deliverables:
- D7: WW treatment process design (Responsible partner: UNIRO Report M9)
- D14: Photoreactor final design (Responsible partner: TUC - Report M15)
- D15: P &I design (Responsible partner: LABOR Report M15)
WP6 PHOTOMEM pilot plant implementation and beta tests.
The main objectives of this WP were the implementation of a WW treatment plant and the performance of beta tests on the plant allowing the assessment of the technology performances in terms of COD removal and fouling issues. Expected deliverables:
- D18: PHOTOMEM Pilot plant (Responsible partner: LABOR - Prototype M21)
WP7 Field tests and results assessment.
The activities planned for this WP intended to reach the following objectives: i) to realize a field tests campaign with real OMWW, and ii) to assess results and evaluate the technical and economical impact of the PHOTOMEM technology. Expected deliverables:
- D19: Field tests results (Responsible partner: ECS - Report M24)
WP8 Dissemination, exploitation and training
The main objective of this WP was to facilitate the take-up of results by the small and medium-sized entreprises (SME)s, in particular by defining a dissemination, knowledge management and IPR protection strategy, as well as a route for the exploitation of PHOTOMEM results and for the transfer of the generated know-how to the small and medium-sized entreprises (SME)s.
Expected deliverables:
- D3: Website (Responsible partner: ECS Other M3)
- D12: Interim plan for use and dissemination of foreground (Responsible partner: ECS Report - M16)
- D17: PHOTOMEM brochure (Responsible partner: ECS Other M18)
- D20: Final plan for use and dissemination of foreground (Responsible partner: ECS Report M24)
WP9 - Project Management: the management tasks throughout the whole project were devoted to the implementation, the monitoring and maintenance of the Consortium agreement, performing an overall, ethical, financial and administrative management aiming at the full achievement of the scientific and technological objectives of the project (No deliverables expected for WP9). Details about the specific activities carried out under this WP will be reported in the dedicated section later on in this report.
Project Results:
GENERAL REMARKS
As planned in the description of work, the first year of PHOTOMEM project was aimed at achieving a major part of the results expected for WP1, WP2, WP3, with some preliminary results coming from the tests on adsorption and photocatalysis planned in WP4 and WP5. WP8 (Dissemination) and WP9 (Management) started in the first months of the project and have been object of activity for the whole period. The first year of the project had its central goals in:
- The definition of the PHOTOMEM requirements, specifications and layout,
- The identification of the photocatalytic nanoparticles characteristics and their production process outline
- The achievement of some preliminary results, to be confirmed and validated in the second year of the project, on the photocatalytic and adsorption tests,
- The design of PHOTOMEM WW treatment process
RESULTS OF WP1
FRA, as the PHOTOMEM end user has contributed for the identification of the end users requirements, which are summarised below:
1. Amount of OMWW generated. 2000 m3 as an average during the whole campaign.
2. Duration of the production. 5 months as average, from November to March.
3. Current discharge route of the OWMM and associated costs. Disposal of OMWW at an evaporation pond at the surroundings of the olive mill. Annual cost of about 10,000 EUROS to rent the ground for the construction of the evaporation pond.
4. Expected requirements with regards to COD removal (expected use) and polyphenols recovery. The main constrain is to fulfil the legal requirements with regards to the effluent. Therefore, the system proposed should at least reduce the pollutants in the effluent to comply with the legislation. The polyphenols recovery is a good option to support the investment of the system through its commercialisation.
5. Capacity/size. The system should be capable of treating all the generated OMWW (average 2000 m3/y). Moreover, it should be close to the olive mill premises in order to avoid extra transportation cost.
6. Investment and O &M costs, how much could they invest. The investment cost would be at about 10,000 to 15,000 Euros per year.
7. Trained operators. The system should be easy to operate and maintain as the end user sees as a problem to have an operator only dedicated to this work.
The different stages foreseen for our project are briefly described below.
1. Pre-treatment by flocculation
The first operation of the treatment of OMWW is necessarily the elimination of the suspended solid, which consists of organic and inorganic compounds. A fraction of the dry substance is present as suspended solid, which is around 1 % of the overall mass. A preliminary separation of the suspended solid is made by a coarse grinding, then a flocculation is performed by adding a flocculant to the OMWW and applying a suitable procedure in batch mode, through two subsequent stages of agitation and solid segregation by using a cylindrical apparatus fitted with a stirrer.
2. Photocatalysis Assisted by Doped TiO2
Heterogeneous photocatalysis, based on the interaction of light and nanoparticles has emerged as an innovative and promising technique for wastewater purification. Titanium dioxide (TiO2) is the catalyst most commonly used today because of its high performance, low cost, high photoactivity, low toxicity, chemical stability, insolubility and resistance to photo corrosion.
3. Membrane Processes
Different pre-treated olive mill waste water samples were used in the past for membrane process experiments. In case of coagulation, the treatment was done in batch mode by using a 20 L reactor using as flocculant aluminium sulphate ('AS'). The coagulant mass was changed and added to the wastewater, at a high stirring rate. After the fast mixing regime which lasted a couple of minutes, the suspension was mixed slowly for 20 more minutes and afterwards stirring was stopped.
4. Post-treatment processes by photocatalysis
The organic matter content of the RO permeate exiting the membrane process step could be, in some cases, still too high to permit discharge in the municipal sewer system. In this case an additional post treatment step should be necessary to reduce the residue organic matter content for the water disposal. This kind of RO permeate, which may exhibit COD values smaller than 2000 mg/l and is transparent, may be treated again by photocatalysis, using nano-TiO2 as catalyst. This time, since the wastewater stream is not opaque, the irradiation with UV is easier and more efficient.
5. Polyphenols Recovery
OOMW contains a polyphenolic fraction (up to 3 g/l in the fresh material) whose composition is variable. Several low-molecular-weight phenolic compounds are present such as, for instance, the phenolic derivatives of hydroxycinnamic, ferulic and caffeic acids and, in larger amounts, tyrosol (4-hydroxyphenetil alcohol) and hydroxytyrosol (3,4-dihydroxyphenetil alcohol). Hydroxytyrosol (3,4-dihydroxyphenylethanol; DOPET) is a phytochemical with antioxidant properties; it is the most powerful antioxidant contained in olive oil and, after gallic acid, one of the most powerful antioxidants.
RESULTS OF WP2
Detail of activities:
1. Development of a procedure for core magnetic particles, based on Fe(II) precipitation followed by oxidation with H2O2.
2. This procedure was then transferred to MT for scale-up.
3. Validation by X-Ray diffraction and transmission electron microscopy (TEM) was performed on the samples.
4. A procedure for silica coating based on Stober process, and validation by dissolution test, zeta potential measurement and TEM observation were carried out. Alternative process by silicate acidification and recipes were transferred to MT.
5. The procedure for titania coating based on titanium tetrabutoxide hydrolysis was used, while an alternative recipe based on mixing at controlled pH silica coated magnetite particles with amorphous titanium oxide precipitated from oxychloride was also tried. The validation stage has been performed via photocatalytic tests, XRD, TEM
In this activity, contribution to the research on the nanoparticles production came from UNIRO, who produced magnetic core nanoparticles, according to the following process:
- Production of nanoparticles of magnetite (FeO.Fe2O3) from the reaction between FeCl3 and Na2SO3 and subsequent processes (precipitation of the iron hydroxide, in presence of ammonia, by evaporation and calcination);
- Production of silica nanoparticles by sol-gel method and subsequent calcination and their addition to magnetite ferromagnetic particles as coating;
- Production of titania by sol-gel method and subsequent drying and mixing of the obtained powder with the nanoparticles produced in the step 2. The obtained nanoparticles are submitted to calcination at a temperature higher than 450 °C to transform TiO2 to the anatase phase, which holds high photocatalytic properties.
i) Synthesis of Fe3O4 nanoparticles
A production procedure of magnetite (Fe3O4) has been optimized. This method leads to pure magnetic particles (particle size control 50 to approximately 80 nm). We consider that this protocol is satisfactory and there is no need for alternatives.
ii) Silica coating of magnetite particles - synthesis of Fe3O4@SiO2
The Stober (TEOS) coating procedure was chosen over the silicate coating (previously investigated) to be the most efficient method to obtain a uniform coating protecting perfectly the magnetite particle from dissolution in acidic media. Some dissolution of magnetite with time was observed in the case of particles coated by the silicate method. The quantity of silica was calculated from the value of the specific surface area of magnetite particles and the targeted thickness of the shell (for instance in the range 5-10 nm), assuming a homogenous and dense shell of amorphous silica of volumic mass 2.2 g.cm-3. The dissolution test proves that all particles may be considered as coated and that the silica coating produced by the Stober method is homogenous and dense.
iii) Synthesis of Fe3O4@SiO2@TiO2 particles
Different approaches and methods were considered and investigated to select a method that would allow the most uniform and efficient anatase coating. First, the so-called TBOT hydrolysis procedure (widely studied in the literature) was evaluated and optimized for our purposes. The method has shown to lead to a quite good anatase coating on the Fe3O4@SiO2 particles.
RESULTS OF WP3
The catalyst KM110511 yields higher MB degradation rate than the KM110512 sample, achieving almost total MB removal within 40 min of photocatalytic treatment under UV-A irradiation. The catalysts Kronos 7101, 7100, 7000 and Degussa P25 seem to be the most suitable to degrade organic pollutants such as phenolic compounds that are usually found at OMWW, in the presence of solar irradiation. The optimal catalyst concentration for the photocatalytic treatment of OMWW was estimated at about 2 g/L TiO2. Kinetic simulation of the photocatalytic process showed that experimental data indicate a zero-order chemical reaction, in terms of COD removal. Application of photocatalytic treatment, in the presence of solar irradiation, at OMWW with high initial COD0, of 65 g/L, is not feasible. Increasing treatment time the energy consumption is substantially increased.
Further oxidant addition in reactant mixture was not investigated in order to prevent
(a) the increase of treatment cost,
(b) the interference of H2O2 with COD measurements, and
(c) the hydrogen peroxide scavenging of the photogenerated oxidizing species (i.e. valence band holes and hydroxyl radicals), thus reducing process efficiency.
The main results of the research carried out in this WP by TUC, already reported in D9, can be summarized as follows:
- The catalyst KM110511 yields higher MB degradation rate than the KM110512 sample, achieving almost total MB removal within 40 min of photocatalytic treatment under UV-A irradiation.
- The catalysts Kronos 7101, 7100, 7000 and Degussa P25 seem to be the most suitable to degrade organic pollutants such as phenolic compounds that are usually found at OMWW, in the presence of solar irradiation.
- The optimal catalyst concentration for the photocatalytic treatment of OMWW was estimated at about 2 g/L TiO2.
- Kinetic simulation of the photocatalytic process showed that experimental data indicate a pseudo-zero order chemical reaction, in terms of COD removal.
- Application of photocatalytic treatment, in the presence of solar irradiation, at OMWW with high initial COD0, of 65 g/L, is not feasible.
- Increasing treatment time the energy consumption is substantially increased. Hence, the increase of the photocatalytic treatment time will not constitute an energy- and thus cost-effective solution for process performance.
- Experiments were not performed by artificial irradiation of higher energy power than 400W, in order to apply an efficient photocatalytic process from both an environmental and economic point of view.
- Increasing hydrogen peroxide addition up to 0.1 g/L had a beneficial effect on treatment performance in terms of COD reduction.
- KM110511 achieved optimal photocatalytic efficiency after only 1 h of treatment when COD removal was 26%.
- Optimal treatment time for the efficient oxidation of an OMWW effluent with an initial COD0 of 0.6 g/L, is estimated at 1 h, in the presence of magnetic TiO2 nanoparticles.
- When the effluents COD (i.e organic compounds including toxic substances, such as polyphenols) at the end of the treatment is substantially low, eco-toxicity of the OMWW sample decreases.
- Practically, KM110511 catalytic activity after three consecutive runs, with regard to COD removal, remained unchanged.
RESULTS OF WP4
In task 4.1 the experimental results about adsorption tests performed by resins on a nanofiltration concentrate of a pre-treated 3-phase OOMW were obtained. Aim is the recovery of marketable polyphenols, mostly importantly hydroxytyrosol.
The raw OMWW used during the experimental work had a concentration of 2086 mg/l of polyphenols. The concentrate of nanofiltration has a value is reduced, down to 1691 mg/l, after the pretreatment steps (that is flocculation, ultrafiltration, nanofiltration), and has no suspended solids. This concentrate was taken as feed streams for the polyphenols recovery process.
The recovery of polyphenols from the feed stream will be performed by adsorption on resins and a subsequent desorption of the captured molecules in an ethanol-water solution. Many resins are available on the market, but only a few are suitable for polyphenol recovery. Three resins, all of them of 'Amberlite' type, were chosen and will be further analyzed by experimental work.
Conclusions
Following the results of the runs described in the project deliverables on the process for recovering Polyphenols, the following design choices will be adopted for the PHOTOMEM plant:
- Polyphenol recovery will be carried out in batch mode. If polyphenol recovery must be made semi-continuous, multiple units of the type described will be required.
- Two packed adsorption column will be used, adopting the same resin (FPX66), the former for dephenolising the nanofiltration concentrate (Dephenolisation Column, DP-C), the latter for recovering the polyphenols contained therein (Depolyphenolisation Column, DPP-C).
- DP-C will be sized and operated in order to minimise polyphenols adsorption while still capturing all phenol.
- DPP-C will be sized and operated in order to maximise polyphenols adsorption and ensure a reasonably long operating time before regeneration. During the adsorption procedure, DPP-C will be arranged so as to be downstream of DP-C.
Column arrangement will be different during the adsorption and desorption phase:
- during the adsorption procedure, DP-C will be arranged so as to be upstream of DPP-C; this way, DPP-C will only target polyphenols recovery without bothering of unwanted compounds. The liquid out flowing from column DPP-C will be sent to wastewater treatment.
- during the desorption procedure, DP-C and DPP-C will be operated in parallel, and each will be fed an ethanol/water mixture.
The liquid out flowing from DP-C is rich in phenol and will be sent to treatment; the liquid out flowing from DPP-C is rich in polyphenols and will be sent to a polyphenol concentration unit (evaporation, or other).
Tests on the adsorption columns for the PHOTOMEM pilot plant
First of all, the general characteristics of the polyphenol recovery unit were determined and are listed below.
- Operating mode: Polyphenol recovery was implemented according to a two-column scheme including a dephenolisation column (which rapidly saturates in polyphenols and continues to adsorb phenol long after polyphenol saturation) and a polyphenol recovery column (which adsorbs polyphenols from the dephenolised product.
- Working volume: the volume of the adsorption columns will will be 0.5 L for both columns. Packing height will be 10 cm for the dephenolisation column and 20 cm for the polyhenol recovery column.
- Materials: the adsorption columns will be in contact with an aqueous solution during adsorption and with an ethanolic solution during the desorption phase; consequently the column material will require compatibility with organic solvents. For the pilot plant, both columns will be manufactured in glass.
The resins will be:
- For the dephenolisation column, the FPX66 resin by Rohm and Haas;
- For the polyphenols recovery column, the MN202 resin by Purolite
RESULTS OF WP5
First of all, the general characteristics of the pilot photocatalytic unit were determined and are listed below.
Operating mode: the pilot photocatalytic reactor will operate at batch mode, while the whole process time for each photocatalytic run will be 3h (i.e. 1 h for catalyst treatment and 2 h for the photocatalytic oxidation of OMW).
Working volume: the volume of the photocatalytic reactor tank will be 350L (about 350000cc in volume).
Catalyst treatment tank: the volume of the catalyst treatment tank will be 150 L.
Materials: all the tanks will be constructed by stainless steel (SS316) as OMW is slightly acidic it requires special non-corrosive materials.
Photocatalytic Reactor Shape and Geometry
There are various designs of photocatalytic reactors that can be selected for the photocatalytic treatment of OMW. The lab-scale experiments were conducted in an open rectangular photocatalytic reactor (20cm × 11cm ×5 cm) operating in batch mode. The UVA lamp was placed on the top of the reactor and the distance between the lamp and the liquid surface was 3.7 cm, while the depth of the reaction solution was 1.3 cm.
To adapt a reactor having the suitable capacity to PHOTOMEM project, two main aspects must be taken into account:
- The scale-up factor: the aim of the pilot plant scale is processing about 1m3/24h of OMW split in three batch processes of 350L/3h each. Such mass flow rate requires huge dimensions of the parts and influences the choice of the construction materials, preferring stainless steel over glass, guarantying minor costs, an easy manufacturing and heavy toughness;
- The UV diffusion: the choice of steel, instead of glass, obviously implies that the most convenient placement of the UV lamps must be now considered. The main advantage related to glass, that of transparency, is in fact no more present when taking into account this configuration, and the same OMW, even if previously subject to flocculation, presents a percentage of particles matter which obstructs the diffusion of light.
So, taking in account both issues, two solutions were proposed to the partners.
Final design of the photoreactor
The tests performed at laboratory scale level suggested the best configuration regarding the shape of the photoreactor which will be used in the PHOTOMEM pilot plant. In the end the external tube airlift configuration proven to be more effective than the internal draft tube so the sizing of the reactor was adjusted to the working volume of 350L, able to cover a total of 1m3 of OMWWs treated daily. A laboratory scale reactor is easy to handle, works with low volume of liquids and doesn't need particular attention regarding its toughness. On the other hand, a pre industrial scale reactor like the one intended in the project must deal with these issues.
Even if it is mandatory to take into account the importance of the light diffusion, it is impossible to build a 350L reactor made of glass and/or quartz both for economical and for resistance reasons.
Therefore the reactor will be made of stainless steel. Even if the the scale up of the reactor can appear easy, some issues must be well evaluated:
- The lamps disposition: 30 UVA lamps (30W each) will be placed around the Plexiglas transparent cylinder in the upper region of the riser, while 3 UVA lamps (60W each) will be submerged into the riser. This is directed to maximise the UV total output voltage to ensure a good radiation during the photocatalysis.
- The plexiglas cylinder: usually the plexiglas adsorbs the UV light. On this purpose a special Plexiglas is used: PLEXIGLAS 7H whose UV absorbance in function of the wavelength can be observed. This kind of material still is blocking UV light but only the low region of the UV spectrum, under 300nm, having a good transparency in the high region of the spectrum up to 95%.
Conclusions
The photoreactor was designed to keep it as easy as possible, without losing efficiency, and as flexible as possible in order to permit a wide-spread study of the operating conditions. The flexible design of the apparatus will allow multiple investigation and evaluation of the efficiency of the process, concluding an optimization of the best suitable operating conditions to maximize the recovery yield of the suspended ferromagnetic nano-particles by assisted sedimentation of magnetic fields and of the organic matter reduction.
Task 5.3 of this WP produced as main output the P&I scheme of the overall PHOTOMEM process. Deliverable D15 P&I, illustrates every single step of the process, which is composed of 6 sections:
i) Section A Flocculation;
ii) Section B Photocatalysis;
iii) Section C Ultrafiltration (UF);
iv) Section D Nanofiltration (NF);
v) Section E Reverse Osmosis (RO);
vi) Section F Adsorption;
- Section A - The first section covers a pretreatment step, the flocculation, where the OMWW is treated by means of a new optimized flocculation process method, where a preliminary separation of the suspended solids is made by first an acidification followed by a temperature ambient recirculation of the OMWW stream. The process permits to reduce the COD content up to 50% and the recovery of 90% of the initial wastewater volume after decantation of the suspended solid by means of gravity force once the recirculation is stopped.
- Section B - The second section of PHOTOMEM project is photocatalysis, which proposes a novel technical solution based on degradation of organic pollutants through photocatalytic UVA irradiation using ferromagnetic particles of titanium dioxide to reduce the COD content of OMWWs. Therefore the industrial production process for ferromagnetic photocatalytic nanoparticles was optimized covering the particles with titanium dioxide through sol-gel coating.
The advantages of this catalytic step are:
- the photocatalytic oxidation with TiO2 is effective under UVA light in destroying a wide range of contaminants in aqueous phases, the COD can be removed by treating OMWWs with 1-3 g/l of TiO2 for few hours;
- TiO2 shows high resistance to corrosion, biological immunity and relatively low cost. The particles can be recovered up to 98% through the use of a magnetic filtering system;
- Oxidation of organic compounds with photocatalytic nanoparticles is much more effective than conventional ways: COD reduction is up to 2 times faster.
- Section C-D-E - The third step of the PHOTOMEM process is a membranes process which involves three similar sections: section C ultrafiltration, section D nanofiltration and section E reverse osmosis. PHOTOMEM optimized this membrane multi-stage process which is capable to separate pollutants from up 85% of the wastewater and to reduce its COD content.
- Cleaning of the membranes - the cleaning membrane procedure is started when a pressure active control related to the membranes process is activated. To clean the surface of the membranes the clarified waters deriving by the end of the reverse osmosis and collected in tank T09 are used.
- Section F - The last step of the PHOTOMEM process is a packed column adsorption process having the aim to recover the polyphenols content inside the OMWWs and selling them to the nutraceutical/cosmetics markets for the reduction of the net cost of the treatment.
- The control system - The control system is capable to supervise each single operation of the pilot plant.
RESULTS OF WP6
The main output of the work carried out in this WP is the PHOTOMEM pilot plant located at LABOR facilities in V. Giacomo Peroni 386, 00131 Rome, Italy.
Following the P&I scheme of the process, the different steps of the treatment were implemented in the plant as follows:
1. Flocculation
Olive Mill Waste Waters (OMWWs) collected from oil mills are stored into T02. Then they are pumped into flocculation reactor R01, where the pH is adjusted by means of a peristaltic pump connected to a nitric acid solution, while they are circulating. Once the correct value of the pH is achieved the circulation is kept for 20 minutes, flocculation phase, then the circulation stops and a 23-hour sedimentation phase begins.
2. Photocatalysis
The clarified OMWWs from flocculation are stored into a intermediate storage tank T03 to allow flocculation start another run, then the first batch of waters (working volume 350L) are loaded into the photoreactor. The catalyst, the magnetic core titanium dioxide nanoparticles, is added, the air flow and the UVA lamps are switched ON and the photocatalysis starts for 4 hours.
Once ended, the photoreactor is depleted by means of a centrifuge pump which pumps the OMWWs through the magnetic trap where the nanoparticles are retained switching ON electromagnets.
The pilot photoreactor is made of:
- A tank of 0.5 m3 capacity, filled up to 350 liters, with a wooden board on the top to support the lamps, a marine propeller with 4 PVC draft tubes, each provided with a sparger, and a PVC piping air system;
- On the bottom side of the board 24 UVA lamps (each rate 30W) are mounted to irradiate the liquid surface with the UV needed for the photocatalysis;
- Four draft tubes placed inside the reactor, to reproduce the behaviour of four internal draft tube airlift reactors;
- The air inlet piping system providing air to the draft tube air lifts to generate the conditions of recirculation of the water and provide oxygen for the photocatalysis to happen: four branches each one ending in the bottom centre of each draft tube;
- A propeller placed in the centre of the reactor to help maintain the catalyst in suspension
3. Magnetic trap
The recovery of the nanoparticles is performed by means of a Plexiglas magnetic trap, in the shape of a vertical cylinder inside which a septum is placed to force the flowing of the waters, rich in nanoparticles content, in a U-shape route through the bottom of the cylinder. The magnetic trap is placed on the top of a chessboard, having square holes where up to 16 super magnets can be inserted.
4. Membrane process
The three membrane processes, UF-NF-RO, are working in series. They work in the same way, i.e.: photocatalysed OMWWs are circulated from UF tank T04 through the corresponding membrane module M01 where the concentrated is separated from the clarified waters to return into T04. Clarified waters fill the NF tank T05 and the next membrane step starts.
The only difference with filtration is that the concentrated waters deriving from UF are discharged while the ones from NF and/or RO can be redirected to section F adsorption for the recovery of polyphenols. Each membrane module contains 4 radial membranes and it is connected to its respective tank:
- Ultrafiltration (UF): 4 UF membranes inserted into UF/M01 module connected to UF/T04 tank;
- Nanofiltration (NF): 4 NF membranes inserted into NF/M02 module connected to UF/T05 tank;
- Reverse Osmosis (RO): 4 RO membranes inserted into UF/M03 module connected to UF/T06 tank.
5. Adsorption
The column feeding tank T07 collects the residues of the NF process. The residues are therefore irculated through the packed column R03 where polyphenols are trapped inside the resin filling the column. The adsorption phase lasts 3 hours and the waste is discharged switching the three-way valve V14 into right, R, position.
6. The control system
The control system of the PHOTOMEM pilot plant, as illustrated in deliverable D15, is able to supervise each single section of the process. It controls:
- Sensors: in order to read the most important process parameters in real time and step-in taking decisions according to the read values;
- Actuators: such as on-off and regulation valves to allow flow control, peristaltic, volumetric and centrifuge pumps for liquid transfer and pressurization;
RESULTS OF WP7
Two operations were performed at pilot plant lab scale: the polyphenols recovery and the post-treatment, consisting in a photocatalytic reactor, assisted by immobilized nanostructured TiO2 catalyst. This latter operation was adopted to reduce the COD content under 0,5 g/l. Chemical oxygen demand (COD) measurements were made by applying the Standard Method 5520 C. pH measurements were performed by using a Mettler Toledo EL120 instrument. Electro conductivity (EC) was measured by using a Delta Ohm HD9021r2 instrument.
During flocculation the following steps were performed:
1. addition of nitric acid solution (36% in weight) to the feedstock in order to reach a pH value equal to 3.2 in strong mixing conditions.
2. slow mixing for a period of 20 minutes, used to favour mixing.
3. Finally, flocculation takes place within the next 23 hours, during which the suspended solids - while flocculating -aggregate and give sedimentation.
The 10% of the feedstock at the bottom of the flocculation reactor is discharged and collected as mud. The remaining 90%, as clarified wastewater is sent to the next process step: Photocatalysis. The water was left to sediment for 24 hours, obtaining a well defined separation between the mud and the clarified phase. The water, as expected, results rich in solid residues. The same process of flocculation was performed on 1m3 of raw OMWWs by means of the reactor R01 of the PHOTOMEM pilot plant.
At the end of the process two samples were taken:
- one of clarified water, from the top of the flocculation reactor;
- one of muds, from the bottom of the flocculation reactor;
Again the two samples were analyzed in lab to investigate the flocculation stage performed on a huge amount of waste waters, to compare the efficiency between a laboratory scale and a pilot plant scale.
Photocatalysis was performed by using the backup photoreactor developed and described in in detail in 'paragraph 2 Section B Photocatalysis' of Deliverable D18, by using the protocol developed and described in the same document.
The tests carried out consist in:
1. addition of 2g/l of ferro-megnetic titania nanophotocatalyst to the feedstock
2. implementation of the photocatalysis for 4 hours, under the UV light (24 lamps having a total consumption of 720W with a wavelenght of 365nm) and the air supply (air flow rate equal to 200 Nm3/h)
3. Recovery of the photocatalyst through the magnetic trap described in 'paragraph 2.2 Magnetic Trap'.
4. The 100% of the feedstock is sent to the next process step, that is ultrafiltration.
Tests for Utrafiltration, Nanofiltration and Reverse Osmosis were performed by using the plant section and the protocol described in detail in 'paragraph 3 Section C-D-E Membrane processes' of Deliverable D18.
The tests on Ultrafiltration consisted in:
- separation by using 4 Desal Osmonics spiral wounded membrane modules (type GM 4040F), featuring a total membrane area of 32 m2 with a pore size about 2nm. The operating pressure was optimized during the testing phase to 4 bar, to maximize productivity without incurring in severe fouling.
Tests on Nanofiltration were performed as follow:
- separation by using 4 Desal Osmonics spiral wounded membrane modules (type DK 4040F), featuring a total membrane area of 32 m2 with a pore size about 0.2nm. The operating pressure was optimized during the testing phase to 8 bar, to maximize productivity without incurring in severe fouling.
Tests on the Reverse Osmosis were performed as follows:
-separation by using 4 Desal Osmonics spiral wounded membrane modules (type SC 4040F), featuring a total membrane area of 32 m2. The operating pressure was optimized during the testing phase to 25 bar. Fouling is not a severe issue here, therefore the minimum operating pressure capable to guarantee maximized selectivity was chosen. The recovery of the polyphenols was performed by using the protocol previously developed and described in detail in 'paragraph 4 Section F Adsoprtion' of Deliverable D18 - PHOTOMEM Pilot Plant.
- Operating mode: Polyphenol recovery was implemented according to a two-column scheme including a dephenolisation column (which rapidly saturates in polyphenols and continues to adsorb phenol long after polyphenol saturation) and a polyphenol recovery column (which adsorbs polyphenols from the dephenolised product.
- Working volume: the volume of the adsorption columns is about 0.5 L for both columns. Packing height is 10 cm for the dephenolisation column and 20 cm for the polyhenol recovery column.
- Materials: the adsorption columns is in contact with an aqueous solution during adsorption and with an ethanol solution during the desorption phase; consequently the column material requires compatibility with organic solvents. For the pilot plant, both columns are manufactured in glass.
Post-treatment
Both the organic matter content and the pH value of the RO permeate exiting the membrane process step could be, in some cases, still not within the limits to permit discharge in the municipal sewer system. In this case an additional post treatment step should be necessary to reduce the residue organic matter content and the pH value adjustment for the water disposal.
This kind of RO permeate, which may exhibit COD values smaller than 2000 mg/l and is quite transparent, may be treated again by photocatalysis, using nano-TiO2 immobilized over glass spheres as catalyst. This time, since the wastewater stream is not opaque, the irradiation with UV is more easy and efficient. Therefore, immobilized nano-TiO2 on glass spheres in a reactor may be used.
The PHOTOMEM process is effective to reduce the COD content to values in line with the limits imposed by legislation.
One of the objectives of the project is to make the initial investment of the plant and the cost of treatment acceptable, in line with the present cost of disposal for mill wastewater (which is nowadays around 30-40/m3).
Furthermore, the recovery of Polyphenols at the end of the treatment is meant to further reduce the final net cost of the overall treatment.
In this section an estimation of the investment and operational costs associated to each step of the PHOTOMEM process is reported for a plant of 40 m3/day, so as to compare them with the initial objective and to be able to evaluate with the support of the small and medium-sized entreprises (SME) working in the project and operating in the sector the attractiveness and the commercial potential of this solution for the wastewater sector.
For ease of reading, we will highlight:
i) The costs of the components of the plant that will bring to a final evaluation of the initial investment associated to a 40m3/day plant using the PHOTOMEM process;
ii) The costs of operation of the same plant for an estimation of the cost per m3 of OMWW treated.
The indicators identified at the beginning of the project showed a cost of less than 300.000 EUROS for the 40m3/day plant (investment), and a cost of operation reduced respect to the current 40 EUROS/m3 estimated for the existing technologies and disposal treatments.
Total cost per day
The estimation of the costs of operation of the plant comes as a consequence from the values reported above. The depreciation over the 15 years hypothesized for the plant itself has been calculated accordingly.
The parameters used for this estimation are the following:
1) The days of operation along one year (estimated: 135 days);
2) The hours of operation of the plant in one year (135 days x 24 hours a day = 3.240);
3) The capacity of the plant, 40 m3 treated per day;
4) The cost of chemicals;
5) The cost of electricity;
6) The personnel costs;
7) The daily depreciation cost including the maintenance cost;
The estimated cost of operation is of the order of 60 EUROS/m3, which is slightly higher than current treatments (40-50 EUROS/m3) However, the cost can be optimized with the following measures:
- recovery of polyphenols which are added value products which can have an outstanding market value (refer to the following paragraph)
- reduction of the membrane size and operating pressure, reducing the installation, maintenance and operational costs. This aspect is considered to be feasible due to the presence of the pretreatment realized by flocculation and photocatalysis. A centrifuge could be included in the plant to reduce the charge experienced by the membranes.
- reduction of the cost of the MAG TiO2 nanocatalyist for the operation, which represents the most relevant share of the cost of operation.
This can be achieved by:
a. optimization of the production costs of the Nanoparticles
improvement of the regeneration of the nanocatalysts. The number of batches after which the nanocatalyst cannot be regenerated, now estimated to be 8, should be verified in detail with further tests. Also a stronger regeneration process could be studied and assessed. In case it would be verified the possibility to regenerate the nanocatalyst for 12 cycles (3 days) the cost of the nanocatalyst would be reduced of 33% and the total cost of the OMWW treatment would be reduced to 46 /m3.
Conclusions
Following the results of the tests carried out on OMWW collected from an Italian olive mill near Rome, it is evident that:
- 75.3% of the initial raw OMWW was obtained as purified wastewater solution to discharge into a municipal sewer system.
- The photocatalysis assisted by the developed magnetic core TiO2 catalyst was quite effective, leading to a COD reduction of 35 %.
- The magnetic trap was able to recover 96% of the magnetic photocatalyst.
- The separation by membrane processes exhibit an overall effectiveness as expected, however the separation by NF was better than predicted, whereas the RO underperformed.
- In order to get the COD target of 500 mg/l a post-treatment based on photo-catalysis assisted by immobilized nanostructured TiO2 was applied. This operation not considered in the proposal, was developed during the project.
- The process recovery of polyphenols represented the hardest task to be achieved, because of the presence in the OMWW of phenols which was unpredicted at the time of the proposal submission. The presence of phenol fostered a process development based on a two stages adsorption.
An economic evaluation of the investment and operation costs of the PHOTOMEM plant scaled up to a common treatment capacity for a medium olive mill (40m3 of WW treated per day) was performed. As it can be seen from the results of such analysis:
a) The target of the 300.000 EUROS investment for the plant was achieved: from the costs of equipment and accessories for assembling the plant it is evident that a major part of the investment is due to the necessity to have a high number of modules for the membrane stage, which represents a core step in the purification process of the plant. High costs are also associated to the purchase of the tanks and reactors for the treatment, to the electric wiring and cabling, to the start up phase of the plant and to the use of valves and UV lamps.
b) The target of reducing the operation costs respect to the current estimation of 40/m3 has been exceeded: in fact, this initial requirement has not been reduced. This refers to a mean value for the treatment of olive mill wastewaters with other techniques respect to the ones constituting the PHOTOMEM technology. This one makes great use of chemicals and of a catalyst for the photocatalytic step which, even for high production quantities, remains quite an expensive consumable.
RESULTS OF WP8
In this WP, two important documents summarizing the intentions of the partner small and medium-sized entreprises (SME)s in the Consortium to disseminate and exploit PHOTOMEM results were produced: the first is the Interim Plan for Use and Dissemination of Foreground, and the second is the final version of this deliverable, the Final PUDF, completed with the latest considerations on the achieved results and on the basis of the performances obtained during the field tests on the plant. We hereby summarize the main results that this WP produced in the whole project duration.
Public Deliverables and Brochures
The partner small and medium-sized entreprises (SME)s specifically requested and arranged to have 3 different materials for dissemination:
- Brochure for dissemination purposes,
- Brochure with technical aspects of the project,
- The project poster
The reason for this choice is mainly due to the intention, of the project partners, to differentiate the tool to be used with the target audience; in particular:
- The brochure for dissemination is intended as an immediate and communicative material, that can be spread to any type of public, not specifically expert in technological fields or in the sector addressed by the PHOTOMEM project. This material can reach any type of public, and proves easy to read, rich in bullet points summarizing the objectives and the results expected from the research, and highlighting the improvements that this innovative treatment aims at providing to the wastewater market sector in the reference countries and in Europe.
Furthermore, to reach a wider audience and with the purpose of allowing the beneficiary small and medium-sized entreprises (SME)s to reach any of their already ongoing contacts with dedicated materials, the partners also arranged for a translation of these brochures into the Consortium languages, in particular:
- ECS translated into Italian the 2 brochures,
- MT translated them into French,
- BIOAZUL translated them into Spanish, and
- FRA translated the brochures into Greek,
- The technical brochure is intended as a more detailed description regarding the research leading to the PHOTOMEM project results, thus represents an optimal tool to be diffused among the technical staff of the existing wastewater plants, either technicians or plant responsible; this brochure shows the different steps of the process, going into detail of each of them. It therefore supports the communication with the expert audience, to whom the specifications and the layout of the overall process can be described accurately.
- A dedicated, specific dissemination material of immediate impact, especially when participating to national or international events of relevance in the industrial wastewater sector , is the project poster. In fact, it can be used for several purposes, when organizing seminars or dedicated speeches to the target audience, or when taking part to fairs or exhibitions to show the innovation behind the project.
Newsletter and Contacts
In order for the project to be duly disseminated to a representative group of companies belonging to this type of audience, the project partners, and the small and medium-sized entreprises (SME)s in particular, identified, thanks to their networks and already established contacts, a list of potentially interested small and medium-sized entreprises (SME)s to be involved in the diffusion of news about PHOTOMEM. The main tool used for these contacts was the newsletter via mailing. Appendix II of the PUDF Deliverable reports the list of companies were these updates regarding the project developments were sent. This list has been updated with some other companies through the second period of the project.
As a general rule, each small and medium-sized entreprises (SME) in the Consortium sent a newsletter to the companies listed for their reference countries, so that:
- ECS promotionally emailed the Italian companies involved in the OMWW treatment or oil production in the region of Rome (Lazio),
- BIOAZUL contacted via email the Spanish companies,
- MT the French ones, and
- FRA the Greek ones.
Particular attention was given, by the Technical Manager, in the person of Prof. Angelo Chianese from UNIRO (University of Rome 'La Sapienza' Department of Chemical Engineering) to keeping the contacts with a big player in the market of olive oil production in Italy, Oleifici Mataluni - http://www.oleificimataluni.com/oliodante/.
Events and training to the small and medium-sized entreprises (SME)
As for the participation to events in the wastewater treatment sector, relevant respect to the project scope and technological objectives, demonstration events, as initially planned in the interim PUDF were not possible, due to the assessed delays in the finalization of the pilot plant and the tests sessions necessary for the fulfillment of a proper assessment of the results.
Patent and publication search
Respect to the original patent and publications search performed in the Interim Plan for use and dissemination of foreground deliverable, we now selected only the most relevant ones, having a certain connection to the results developed in PHOTOMEM. This research was of support in the definition of the exploitation strategy, which was intended in the project as a way to take advantage of a new treatment technology, on which no direct application or commercialised product has already been found on the market.
Exploitation Strategy and IPR Management
The concrete output of the IPR Management tasks was the definition of an agreed strategy for the exploitation of the obtained results. The PUDF reports the degree of completion of each specific result of the project, with the missing steps for their commercialization, and the exploitation intention of the owners for the future.
The output of such discussions led to the identification of the following points for the exploitation plan to be adopted by the SMEs for the plant commercialization and exploitation:
1) The photocatalytic reactor developed in the project cannot be exploited as a stand-by result, especially in case of an application for a patent;
2) The production process for the ferromagnetic nanoparticles, owned by the French SME Marion Technologies should not be patented alone, as patenting a process might not be successful if not related to a specific application;
3) The PHOTOMEM plant, because of its commercial potential, will be object of exploitation by the owning partners, ECS and BIOAZUL, and thus patents will not be sought after for this result.
On the basis of these considerations, the partners decided what follows:
The only attractive solution, for the enterprises owning the project results, for the protection of the knowledge generated in the project, is to unify at least 2 results of the project to apply for a patent covering several aspects of the treatment process. In particular, the best option for the protection of the IPs coming from the PHOTOMEM research was considered to be the application for a patent including the design of the photocatalytic reactor using dispersed photocatalytic ferromagnetic titania nanoparticles for the treatment of high COD wastewater.
This strategy would therefore include:
i) The use of result no. 1 - that is, the photocatalytic ferromagnetic titania nanoparticles produced by ARMINES and MT,
ii) The use of part of result no. 2 that is, the procedure outlined for photocatalysis, which represents one of the steps of the overall PHOTOMEM treatment, and
iii) The use of part of result no. 3 that is, the photocatalytic reactor allowing for further reduction of COD contents in the olive wastewater with respect to the traditional techniques.
According to this choice, the intention of the beneficiaries owning this result BIOAZUL, ECOSYSTEMS and MT - is that of performing a deep analysis of the photocatalytic treatment in terms of COD reduction, and to eventually decide to apply for a patent which considers the specific application of photocatalysis, via a photocatalytic reactor with dispersed photocatalytic nanotitania particles, to the treatment of high COD waste water.
In summary, the exploitation strategy for each of the beneficiaries can be outlined:
- ECS , MT and BIOAZUL intend to jointly:
1) Study and evaluate the possibility to patent the photocatalytic reactor with dispersed nanotitania for treatment of high COD content wastewater on the basis of the tests assessment and on the performances of photocatalysis in reducing the organic content in the olive wastewater;
MT intends to:
1) Act as exclusive producer of the ferromagnetic nanoparticles for the PHOTOMEM and other plants installed by ECS and BIOAZUL (and their licensees), provided that:
- they furnish the nanotitania for PHOTOMEM plants at a market value,
- the particles are produced in the respect of the quality standards required for the process.
2) Modify or apply the production process to any other application or for producing other materials;
FRA intends to:
1) Exercise an exclusivity option for the use of PHOTOMEM in Crete for 2 years after the end of the project;
2) Request to have the pilot plant at his facilities after the end of the project, or to have a new plant (at own costs);
ECS and BIOAZUL intend to:
1) Commercialize the PHOTOMEM plant in their countries (Spain and Italy);
2) Use the plant in other WW treatments and to license the results to third parties;
3) Jointly look for a licensee of PHOTOMEM plant in other markets.
On the base of the evaluation of how to proceed with the exploitation actions mentioned above, the PHOTOMEM beneficiaries co-owning results of the project will develop a Joint Ownership Agreement.
Potential Impact:
Each of the participating small and medium-sized entreprises (SME) in the Consortium will receive great benefits and gain competitive advantage by owning the project results as they have been agreed and shared, in relation to each partner's business line.
In fact:
- the proposer SMEs, ECS and BIOAZUL, specialized in the wastewater treatment plants design and construction will strongly benefit from the possibility to sell the PHOTOMEM wastewater treatment plant in 2 different countries (Italy and Spain).
- On the other hand, the producer of custom-made ceramic powders and nanostructured materials for industrial use (MT) intends to produce and provide the ferromagnetic photocatalytic titania nanoparticles.
- Finally, the end-user FRA (Greece) will apply the technology in its production site and will contribute to validate the purification process.
We believe the market potential for such a solution would be of the order of several tens of millions of Euro. The tangible outcomes of the PHOTOMEM project, available to small and medium-sized entreprises (SME) partners for exploitation will be:
1) Production process for ferromagnetic photocatalytic titania nanoparticles
2) Economical wastewater treatment for OMWW based on photocatalytic pretreatment, membrane filtration and polyphenols recovery
3) PHOTOMEM pilot plant of 1 m3/day capacity to validate the OMWW treatment.
The attached file to this report shows a table indicating:
- For each result, the SMEs proposers who are going to have a main role in the exploitation, and the RTD performer who are providing research services,
- Competences and role of the SMEs and RTD performers
List of Websites:
http://www.photomem.eu/.
Olives undergo a series of treatments and operations in order to reach the point at which oil is extracted from them. One of the last steps in olive oil production is the purification and final separation of the olive oil from the residual pulp and an aqueous suspension, called olive mill wastewater (OMWW). The water present in the OMWW is partially added during the process, in major extent in the three phase process. This waste water stream is a strong pollutant because of its high organic load and phytototoxic, due to the presence of antibacterial phenolic substances, resistant to biological degradation. The discharge of OMWW is not allowed trough the municipal sewage system and/or natural effluents. Unfortunately, the available technologies for the wastewater treatment are too complicated to be operated in a mill factory environment and very expensive for to the olive oil business. Aim of the PHOTOMEM project is therefore to define and implement a process for the treatment of wastewater derived from agro-food processing, in particular olive mill wastewater (OMWW) waste water.
Project Context and Objectives:
Mediterranean countries are strongly affected by the serious environmental problem related to the disposal of the olive oil mills wastewater, since they produce 95% of the worldwide olive-oil. In these countries about 11 million tons of olives are produced per year from which around 1.7 million tons of olive oil are extracted. The seasonal polluting load of olive-oil production in these countries is equivalent to the one of 22 million people, since the in average COD value of OM http://www is about 80 g l-1 and its volume is about 0.8 ton per ton of olive. Moreover, this huge amount of polluted wastewater is produced only during 2-3 months per year (average duration of the olive oil campaign), making the storage difficult and entailing the need of an immediate treatment to eliminate its environmental hazard.
As already mentioned, the discharge of OM http://www is not allowed trough the municipal sewage system and/or natural effluents. At the same time, however, no efficient and low-cost treatment exists for the treatment of such effluents to be performed in an industrial environment such as the mill factory one. For this reason, the current disposal systems adopted, which in most of the cases infringe the European and national regulations, are:
- Evaporation: the OMWW and the alpechin are stored in huge tanks or in evaporation ponds and the water is evaporated by sun throughout the year. The main problem are: the storage needs huge tanks, the evaporation leads to bad smelling air and must be performed far away from towns; also, a pollutant rich solid residue is generated and must be disposed.
- Disposal on terrains: the legislation allows disposing OMWW on compatible and suitable terrains (which are relatively rare and need to be toughly monitored) and within certain limits (50-80 m3/ha/y). The available terrains are not sufficient when compared to the quantities produced yearly by an average olive mill factory (20-50 m3/d). The problems caused by this procedure are pollution of the groundwater layers and of the terrains. For this reason, the procedure is considered illegal according to the EU Directive 91/271/EEC on urban waste-water treatment.
Specific activities were carried out in order to obtain the above mentioned goals:
First Reporting Period
- The identification of the characteristics of PHOTOMEM target wastewaters, in terms of the organic matter contents, for the definition of the WW treatment to be applied,
- The definition of the optimal lab procedure for the production of magnetic nanocores and for their coating with silica and titania, based on the comparison between different processes,
- A preliminary evaluation of the photocatalytic process efficiency and the identification of the optimal catalyst for PHOTOMEM reactor,
- The determination of the process for polyphenols recovery and relative adsorption tests, and assembly of all these stages for building up the final WW treatment process.
Second Reporting Period
- The definition of the optimal lab procedure for the production of magnetic nanocores and for their coating with silica and titania, based on the comparison between different processes,
- The subsequent optimization of the production process so as to be able to produce high quantities of nanoparticles for the PHOTOMEM process,
- The determination of the process for polyphenols recovery and relative adsorption tests, and the sizing of an adsorption column to be used after the nanofiltration stage for recovering polyphenols from the treated wastewater,
- The selection of an optimized shape for the photoreactor allowing the scale up to industrially treated volumes of OMWW, obtained by testing different reactor configurations on lab scale prototypes and assessing their performances,
- The final 3D CAD design of the chosen photoreactor including the magnetic trap for the recovery of the nanoparticles used during the photocatalytic step,
- The implementation of the pilot plant, including automation and control
- The realization of beta tests and of a session of tests on fresh OMWW collected in November for the final assessment of the organics removal performed via the PHOTOMEM process.
The main technical outputs of the project were:
- The definition of the PHOTOMEM requirements
- The system specifications and layout
- A detailed report on the produced ferromagnetic nanoparticles characteristics and on their properties
- First results on adsorption and polyphenols recovery tests
- The WW treatment process design
- The realisation of a website dedicated to the project
- A detailed report on the produced ferromagnetic nanoparticles characteristics and on the production process performed by ARMINES in collaboration with MT, with an evaluation of the production costs for the future exploitation of the technology,
- the selection of the air lift configuration for the photoreactor, and its concept and executive design based on hydraulic and photocatalytic tests carried out at lab scale
- the Process and Instrumentation Scheme for the PHOTOMEM plant
- a pilot plant for the treatment of 1 m3/day of OMWW was implemented and tested
- The sizing of the adsorption column by which the recovery of polyphenols was possible in the PHOTOMEM process,
- The results of the tests on the pilot plant, allowing an estimation of the market potential of the PHOTOMEM technology,
On the dissemination and exploitation side, the main goals achieved in the reference period were:
- The estimation of nanoparticles production costs at an industrial scale,
- The implementation of specific dissemination activities having the purpose of spreading the results of the project to an audience as wide as possible,
- The assessment of the impact that the PHOTOMEM technology might have on the market once exploited by the SMEs and the realization of an exploitation strategy for the process and the plant commercialization.
- The update of the project website
The project activities can be thought as structured in 2 main phases:
- Phase 1: the setup of the system specifications and architecture and the preliminary tests on the photocatalytic process, the trials on the nanoparticles production for the identification of the best recipe, and the studies on the polyphenols recovery process (RP1);
- Phase 2: the outline of the process final design, the implementation of the different steps of the process on the PHOTOMEM pilot plant, and the field tests on OMWW with subsequent assessment of the technology performances (partially performed in RP1 and continued in RP2).
The specific objectives of each of the ongoing Work Packages in the whole project, according to the Description of Work, were:
WP1 Specifications and Layout
- Definition of the expected requirements for the WW treatment for the industrial application, expected performances, costs, etc.
- Definition of the technical specifications and draft of the process layout
- Definition of the expected performance of the photocatalytic nanoparticles production process and cost
Expected deliverables:
- D1: PHOTOMEM Requirements (Responsible partner: BIOAZUL - Report M1)
- D2: PHOTOMEM Specifications and Layout (Responsible Partner: UNIRO - Report M3)
WP2 Photocatalytic Nanoparticles Production Process.
This WP was devoted to perform the coating the ferromagnetic nanoparticles with sol gel silica and nanotitania, to carry out the optimisation of nanoparticles production in relation to photocatalytic performance, magnetic recovery, cost, etc., and to finally define an industrially scalable production process for the nanoparticles. Expected deliverables:
- D4: Ferromagnetic photocatalytic nanoparticles characteristics (Responsible partner: ARMINES Report M9)
- D8: Operative conditions for optimal production of ferromagnetic photocatalytic nanoparticles (Responsible partner: ARMINES Report - M12)
- D16: Layout and analysis of scalable production process for ferromagnetic photocatalytic nanoparticles (Responsible partner: ARMINES - Report - M18)
WP3 Development of photocatalytic process and reactor.
WP3 was intended to perform the definition and implementation of a lab setup of photoreactor for the photocatalytic reaction, to make tests on nanoparticles in the reactor and evaluate the COD content removal efficiency and recovery capacity, and, finally, to define the photoreactor design for the PHOTOMEM pilot plant. Expected deliverables:
- D5: Preliminary results of photocatalytic tests (Responsible partner: TUC Report M9)
- D9: Results of photocatalytic tests (Responsible partner: TUC - Report M12)
- D10: Photoreactor concept design (Responsible partner: TUC Report M12)
WP4 - Development of the polyphenols recovery.
This WP was aimed at performing an experimental investigation on the polyphenols adsorption-desorption process, at investigating the feasibility of the polyphenols recovery and at designing the adsorption recovery unit. Expected deliverables:
- D6: Preliminary results of the adsorption tests (Responsible partner: UNIRO Report M9)
- D11: Results of the adsorption tests (Responsible partner: UNIRO Report M12)
- D13: Polyphenols recovery unit design (Responsible partner: UNIRO Report M15)
WP5- WW treatment process design.
This WP had its main goals in the design of a pilot scale photoreactor with a recovery system for nanocatalyst, and in the design of a complete WW treatment pilot plant, integrating the photoreactor with membrane filtration steps. Expected deliverables:
- D7: WW treatment process design (Responsible partner: UNIRO Report M9)
- D14: Photoreactor final design (Responsible partner: TUC - Report M15)
- D15: P &I design (Responsible partner: LABOR Report M15)
WP6 PHOTOMEM pilot plant implementation and beta tests.
The main objectives of this WP were the implementation of a WW treatment plant and the performance of beta tests on the plant allowing the assessment of the technology performances in terms of COD removal and fouling issues. Expected deliverables:
- D18: PHOTOMEM Pilot plant (Responsible partner: LABOR - Prototype M21)
WP7 Field tests and results assessment.
The activities planned for this WP intended to reach the following objectives: i) to realize a field tests campaign with real OMWW, and ii) to assess results and evaluate the technical and economical impact of the PHOTOMEM technology. Expected deliverables:
- D19: Field tests results (Responsible partner: ECS - Report M24)
WP8 Dissemination, exploitation and training
The main objective of this WP was to facilitate the take-up of results by the small and medium-sized entreprises (SME)s, in particular by defining a dissemination, knowledge management and IPR protection strategy, as well as a route for the exploitation of PHOTOMEM results and for the transfer of the generated know-how to the small and medium-sized entreprises (SME)s.
Expected deliverables:
- D3: Website (Responsible partner: ECS Other M3)
- D12: Interim plan for use and dissemination of foreground (Responsible partner: ECS Report - M16)
- D17: PHOTOMEM brochure (Responsible partner: ECS Other M18)
- D20: Final plan for use and dissemination of foreground (Responsible partner: ECS Report M24)
WP9 - Project Management: the management tasks throughout the whole project were devoted to the implementation, the monitoring and maintenance of the Consortium agreement, performing an overall, ethical, financial and administrative management aiming at the full achievement of the scientific and technological objectives of the project (No deliverables expected for WP9). Details about the specific activities carried out under this WP will be reported in the dedicated section later on in this report.
Project Results:
GENERAL REMARKS
As planned in the description of work, the first year of PHOTOMEM project was aimed at achieving a major part of the results expected for WP1, WP2, WP3, with some preliminary results coming from the tests on adsorption and photocatalysis planned in WP4 and WP5. WP8 (Dissemination) and WP9 (Management) started in the first months of the project and have been object of activity for the whole period. The first year of the project had its central goals in:
- The definition of the PHOTOMEM requirements, specifications and layout,
- The identification of the photocatalytic nanoparticles characteristics and their production process outline
- The achievement of some preliminary results, to be confirmed and validated in the second year of the project, on the photocatalytic and adsorption tests,
- The design of PHOTOMEM WW treatment process
RESULTS OF WP1
FRA, as the PHOTOMEM end user has contributed for the identification of the end users requirements, which are summarised below:
1. Amount of OMWW generated. 2000 m3 as an average during the whole campaign.
2. Duration of the production. 5 months as average, from November to March.
3. Current discharge route of the OWMM and associated costs. Disposal of OMWW at an evaporation pond at the surroundings of the olive mill. Annual cost of about 10,000 EUROS to rent the ground for the construction of the evaporation pond.
4. Expected requirements with regards to COD removal (expected use) and polyphenols recovery. The main constrain is to fulfil the legal requirements with regards to the effluent. Therefore, the system proposed should at least reduce the pollutants in the effluent to comply with the legislation. The polyphenols recovery is a good option to support the investment of the system through its commercialisation.
5. Capacity/size. The system should be capable of treating all the generated OMWW (average 2000 m3/y). Moreover, it should be close to the olive mill premises in order to avoid extra transportation cost.
6. Investment and O &M costs, how much could they invest. The investment cost would be at about 10,000 to 15,000 Euros per year.
7. Trained operators. The system should be easy to operate and maintain as the end user sees as a problem to have an operator only dedicated to this work.
The different stages foreseen for our project are briefly described below.
1. Pre-treatment by flocculation
The first operation of the treatment of OMWW is necessarily the elimination of the suspended solid, which consists of organic and inorganic compounds. A fraction of the dry substance is present as suspended solid, which is around 1 % of the overall mass. A preliminary separation of the suspended solid is made by a coarse grinding, then a flocculation is performed by adding a flocculant to the OMWW and applying a suitable procedure in batch mode, through two subsequent stages of agitation and solid segregation by using a cylindrical apparatus fitted with a stirrer.
2. Photocatalysis Assisted by Doped TiO2
Heterogeneous photocatalysis, based on the interaction of light and nanoparticles has emerged as an innovative and promising technique for wastewater purification. Titanium dioxide (TiO2) is the catalyst most commonly used today because of its high performance, low cost, high photoactivity, low toxicity, chemical stability, insolubility and resistance to photo corrosion.
3. Membrane Processes
Different pre-treated olive mill waste water samples were used in the past for membrane process experiments. In case of coagulation, the treatment was done in batch mode by using a 20 L reactor using as flocculant aluminium sulphate ('AS'). The coagulant mass was changed and added to the wastewater, at a high stirring rate. After the fast mixing regime which lasted a couple of minutes, the suspension was mixed slowly for 20 more minutes and afterwards stirring was stopped.
4. Post-treatment processes by photocatalysis
The organic matter content of the RO permeate exiting the membrane process step could be, in some cases, still too high to permit discharge in the municipal sewer system. In this case an additional post treatment step should be necessary to reduce the residue organic matter content for the water disposal. This kind of RO permeate, which may exhibit COD values smaller than 2000 mg/l and is transparent, may be treated again by photocatalysis, using nano-TiO2 as catalyst. This time, since the wastewater stream is not opaque, the irradiation with UV is easier and more efficient.
5. Polyphenols Recovery
OOMW contains a polyphenolic fraction (up to 3 g/l in the fresh material) whose composition is variable. Several low-molecular-weight phenolic compounds are present such as, for instance, the phenolic derivatives of hydroxycinnamic, ferulic and caffeic acids and, in larger amounts, tyrosol (4-hydroxyphenetil alcohol) and hydroxytyrosol (3,4-dihydroxyphenetil alcohol). Hydroxytyrosol (3,4-dihydroxyphenylethanol; DOPET) is a phytochemical with antioxidant properties; it is the most powerful antioxidant contained in olive oil and, after gallic acid, one of the most powerful antioxidants.
RESULTS OF WP2
Detail of activities:
1. Development of a procedure for core magnetic particles, based on Fe(II) precipitation followed by oxidation with H2O2.
2. This procedure was then transferred to MT for scale-up.
3. Validation by X-Ray diffraction and transmission electron microscopy (TEM) was performed on the samples.
4. A procedure for silica coating based on Stober process, and validation by dissolution test, zeta potential measurement and TEM observation were carried out. Alternative process by silicate acidification and recipes were transferred to MT.
5. The procedure for titania coating based on titanium tetrabutoxide hydrolysis was used, while an alternative recipe based on mixing at controlled pH silica coated magnetite particles with amorphous titanium oxide precipitated from oxychloride was also tried. The validation stage has been performed via photocatalytic tests, XRD, TEM
In this activity, contribution to the research on the nanoparticles production came from UNIRO, who produced magnetic core nanoparticles, according to the following process:
- Production of nanoparticles of magnetite (FeO.Fe2O3) from the reaction between FeCl3 and Na2SO3 and subsequent processes (precipitation of the iron hydroxide, in presence of ammonia, by evaporation and calcination);
- Production of silica nanoparticles by sol-gel method and subsequent calcination and their addition to magnetite ferromagnetic particles as coating;
- Production of titania by sol-gel method and subsequent drying and mixing of the obtained powder with the nanoparticles produced in the step 2. The obtained nanoparticles are submitted to calcination at a temperature higher than 450 °C to transform TiO2 to the anatase phase, which holds high photocatalytic properties.
i) Synthesis of Fe3O4 nanoparticles
A production procedure of magnetite (Fe3O4) has been optimized. This method leads to pure magnetic particles (particle size control 50 to approximately 80 nm). We consider that this protocol is satisfactory and there is no need for alternatives.
ii) Silica coating of magnetite particles - synthesis of Fe3O4@SiO2
The Stober (TEOS) coating procedure was chosen over the silicate coating (previously investigated) to be the most efficient method to obtain a uniform coating protecting perfectly the magnetite particle from dissolution in acidic media. Some dissolution of magnetite with time was observed in the case of particles coated by the silicate method. The quantity of silica was calculated from the value of the specific surface area of magnetite particles and the targeted thickness of the shell (for instance in the range 5-10 nm), assuming a homogenous and dense shell of amorphous silica of volumic mass 2.2 g.cm-3. The dissolution test proves that all particles may be considered as coated and that the silica coating produced by the Stober method is homogenous and dense.
iii) Synthesis of Fe3O4@SiO2@TiO2 particles
Different approaches and methods were considered and investigated to select a method that would allow the most uniform and efficient anatase coating. First, the so-called TBOT hydrolysis procedure (widely studied in the literature) was evaluated and optimized for our purposes. The method has shown to lead to a quite good anatase coating on the Fe3O4@SiO2 particles.
RESULTS OF WP3
The catalyst KM110511 yields higher MB degradation rate than the KM110512 sample, achieving almost total MB removal within 40 min of photocatalytic treatment under UV-A irradiation. The catalysts Kronos 7101, 7100, 7000 and Degussa P25 seem to be the most suitable to degrade organic pollutants such as phenolic compounds that are usually found at OMWW, in the presence of solar irradiation. The optimal catalyst concentration for the photocatalytic treatment of OMWW was estimated at about 2 g/L TiO2. Kinetic simulation of the photocatalytic process showed that experimental data indicate a zero-order chemical reaction, in terms of COD removal. Application of photocatalytic treatment, in the presence of solar irradiation, at OMWW with high initial COD0, of 65 g/L, is not feasible. Increasing treatment time the energy consumption is substantially increased.
Further oxidant addition in reactant mixture was not investigated in order to prevent
(a) the increase of treatment cost,
(b) the interference of H2O2 with COD measurements, and
(c) the hydrogen peroxide scavenging of the photogenerated oxidizing species (i.e. valence band holes and hydroxyl radicals), thus reducing process efficiency.
The main results of the research carried out in this WP by TUC, already reported in D9, can be summarized as follows:
- The catalyst KM110511 yields higher MB degradation rate than the KM110512 sample, achieving almost total MB removal within 40 min of photocatalytic treatment under UV-A irradiation.
- The catalysts Kronos 7101, 7100, 7000 and Degussa P25 seem to be the most suitable to degrade organic pollutants such as phenolic compounds that are usually found at OMWW, in the presence of solar irradiation.
- The optimal catalyst concentration for the photocatalytic treatment of OMWW was estimated at about 2 g/L TiO2.
- Kinetic simulation of the photocatalytic process showed that experimental data indicate a pseudo-zero order chemical reaction, in terms of COD removal.
- Application of photocatalytic treatment, in the presence of solar irradiation, at OMWW with high initial COD0, of 65 g/L, is not feasible.
- Increasing treatment time the energy consumption is substantially increased. Hence, the increase of the photocatalytic treatment time will not constitute an energy- and thus cost-effective solution for process performance.
- Experiments were not performed by artificial irradiation of higher energy power than 400W, in order to apply an efficient photocatalytic process from both an environmental and economic point of view.
- Increasing hydrogen peroxide addition up to 0.1 g/L had a beneficial effect on treatment performance in terms of COD reduction.
- KM110511 achieved optimal photocatalytic efficiency after only 1 h of treatment when COD removal was 26%.
- Optimal treatment time for the efficient oxidation of an OMWW effluent with an initial COD0 of 0.6 g/L, is estimated at 1 h, in the presence of magnetic TiO2 nanoparticles.
- When the effluents COD (i.e organic compounds including toxic substances, such as polyphenols) at the end of the treatment is substantially low, eco-toxicity of the OMWW sample decreases.
- Practically, KM110511 catalytic activity after three consecutive runs, with regard to COD removal, remained unchanged.
RESULTS OF WP4
In task 4.1 the experimental results about adsorption tests performed by resins on a nanofiltration concentrate of a pre-treated 3-phase OOMW were obtained. Aim is the recovery of marketable polyphenols, mostly importantly hydroxytyrosol.
The raw OMWW used during the experimental work had a concentration of 2086 mg/l of polyphenols. The concentrate of nanofiltration has a value is reduced, down to 1691 mg/l, after the pretreatment steps (that is flocculation, ultrafiltration, nanofiltration), and has no suspended solids. This concentrate was taken as feed streams for the polyphenols recovery process.
The recovery of polyphenols from the feed stream will be performed by adsorption on resins and a subsequent desorption of the captured molecules in an ethanol-water solution. Many resins are available on the market, but only a few are suitable for polyphenol recovery. Three resins, all of them of 'Amberlite' type, were chosen and will be further analyzed by experimental work.
Conclusions
Following the results of the runs described in the project deliverables on the process for recovering Polyphenols, the following design choices will be adopted for the PHOTOMEM plant:
- Polyphenol recovery will be carried out in batch mode. If polyphenol recovery must be made semi-continuous, multiple units of the type described will be required.
- Two packed adsorption column will be used, adopting the same resin (FPX66), the former for dephenolising the nanofiltration concentrate (Dephenolisation Column, DP-C), the latter for recovering the polyphenols contained therein (Depolyphenolisation Column, DPP-C).
- DP-C will be sized and operated in order to minimise polyphenols adsorption while still capturing all phenol.
- DPP-C will be sized and operated in order to maximise polyphenols adsorption and ensure a reasonably long operating time before regeneration. During the adsorption procedure, DPP-C will be arranged so as to be downstream of DP-C.
Column arrangement will be different during the adsorption and desorption phase:
- during the adsorption procedure, DP-C will be arranged so as to be upstream of DPP-C; this way, DPP-C will only target polyphenols recovery without bothering of unwanted compounds. The liquid out flowing from column DPP-C will be sent to wastewater treatment.
- during the desorption procedure, DP-C and DPP-C will be operated in parallel, and each will be fed an ethanol/water mixture.
The liquid out flowing from DP-C is rich in phenol and will be sent to treatment; the liquid out flowing from DPP-C is rich in polyphenols and will be sent to a polyphenol concentration unit (evaporation, or other).
Tests on the adsorption columns for the PHOTOMEM pilot plant
First of all, the general characteristics of the polyphenol recovery unit were determined and are listed below.
- Operating mode: Polyphenol recovery was implemented according to a two-column scheme including a dephenolisation column (which rapidly saturates in polyphenols and continues to adsorb phenol long after polyphenol saturation) and a polyphenol recovery column (which adsorbs polyphenols from the dephenolised product.
- Working volume: the volume of the adsorption columns will will be 0.5 L for both columns. Packing height will be 10 cm for the dephenolisation column and 20 cm for the polyhenol recovery column.
- Materials: the adsorption columns will be in contact with an aqueous solution during adsorption and with an ethanolic solution during the desorption phase; consequently the column material will require compatibility with organic solvents. For the pilot plant, both columns will be manufactured in glass.
The resins will be:
- For the dephenolisation column, the FPX66 resin by Rohm and Haas;
- For the polyphenols recovery column, the MN202 resin by Purolite
RESULTS OF WP5
First of all, the general characteristics of the pilot photocatalytic unit were determined and are listed below.
Operating mode: the pilot photocatalytic reactor will operate at batch mode, while the whole process time for each photocatalytic run will be 3h (i.e. 1 h for catalyst treatment and 2 h for the photocatalytic oxidation of OMW).
Working volume: the volume of the photocatalytic reactor tank will be 350L (about 350000cc in volume).
Catalyst treatment tank: the volume of the catalyst treatment tank will be 150 L.
Materials: all the tanks will be constructed by stainless steel (SS316) as OMW is slightly acidic it requires special non-corrosive materials.
Photocatalytic Reactor Shape and Geometry
There are various designs of photocatalytic reactors that can be selected for the photocatalytic treatment of OMW. The lab-scale experiments were conducted in an open rectangular photocatalytic reactor (20cm × 11cm ×5 cm) operating in batch mode. The UVA lamp was placed on the top of the reactor and the distance between the lamp and the liquid surface was 3.7 cm, while the depth of the reaction solution was 1.3 cm.
To adapt a reactor having the suitable capacity to PHOTOMEM project, two main aspects must be taken into account:
- The scale-up factor: the aim of the pilot plant scale is processing about 1m3/24h of OMW split in three batch processes of 350L/3h each. Such mass flow rate requires huge dimensions of the parts and influences the choice of the construction materials, preferring stainless steel over glass, guarantying minor costs, an easy manufacturing and heavy toughness;
- The UV diffusion: the choice of steel, instead of glass, obviously implies that the most convenient placement of the UV lamps must be now considered. The main advantage related to glass, that of transparency, is in fact no more present when taking into account this configuration, and the same OMW, even if previously subject to flocculation, presents a percentage of particles matter which obstructs the diffusion of light.
So, taking in account both issues, two solutions were proposed to the partners.
Final design of the photoreactor
The tests performed at laboratory scale level suggested the best configuration regarding the shape of the photoreactor which will be used in the PHOTOMEM pilot plant. In the end the external tube airlift configuration proven to be more effective than the internal draft tube so the sizing of the reactor was adjusted to the working volume of 350L, able to cover a total of 1m3 of OMWWs treated daily. A laboratory scale reactor is easy to handle, works with low volume of liquids and doesn't need particular attention regarding its toughness. On the other hand, a pre industrial scale reactor like the one intended in the project must deal with these issues.
Even if it is mandatory to take into account the importance of the light diffusion, it is impossible to build a 350L reactor made of glass and/or quartz both for economical and for resistance reasons.
Therefore the reactor will be made of stainless steel. Even if the the scale up of the reactor can appear easy, some issues must be well evaluated:
- The lamps disposition: 30 UVA lamps (30W each) will be placed around the Plexiglas transparent cylinder in the upper region of the riser, while 3 UVA lamps (60W each) will be submerged into the riser. This is directed to maximise the UV total output voltage to ensure a good radiation during the photocatalysis.
- The plexiglas cylinder: usually the plexiglas adsorbs the UV light. On this purpose a special Plexiglas is used: PLEXIGLAS 7H whose UV absorbance in function of the wavelength can be observed. This kind of material still is blocking UV light but only the low region of the UV spectrum, under 300nm, having a good transparency in the high region of the spectrum up to 95%.
Conclusions
The photoreactor was designed to keep it as easy as possible, without losing efficiency, and as flexible as possible in order to permit a wide-spread study of the operating conditions. The flexible design of the apparatus will allow multiple investigation and evaluation of the efficiency of the process, concluding an optimization of the best suitable operating conditions to maximize the recovery yield of the suspended ferromagnetic nano-particles by assisted sedimentation of magnetic fields and of the organic matter reduction.
Task 5.3 of this WP produced as main output the P&I scheme of the overall PHOTOMEM process. Deliverable D15 P&I, illustrates every single step of the process, which is composed of 6 sections:
i) Section A Flocculation;
ii) Section B Photocatalysis;
iii) Section C Ultrafiltration (UF);
iv) Section D Nanofiltration (NF);
v) Section E Reverse Osmosis (RO);
vi) Section F Adsorption;
- Section A - The first section covers a pretreatment step, the flocculation, where the OMWW is treated by means of a new optimized flocculation process method, where a preliminary separation of the suspended solids is made by first an acidification followed by a temperature ambient recirculation of the OMWW stream. The process permits to reduce the COD content up to 50% and the recovery of 90% of the initial wastewater volume after decantation of the suspended solid by means of gravity force once the recirculation is stopped.
- Section B - The second section of PHOTOMEM project is photocatalysis, which proposes a novel technical solution based on degradation of organic pollutants through photocatalytic UVA irradiation using ferromagnetic particles of titanium dioxide to reduce the COD content of OMWWs. Therefore the industrial production process for ferromagnetic photocatalytic nanoparticles was optimized covering the particles with titanium dioxide through sol-gel coating.
The advantages of this catalytic step are:
- the photocatalytic oxidation with TiO2 is effective under UVA light in destroying a wide range of contaminants in aqueous phases, the COD can be removed by treating OMWWs with 1-3 g/l of TiO2 for few hours;
- TiO2 shows high resistance to corrosion, biological immunity and relatively low cost. The particles can be recovered up to 98% through the use of a magnetic filtering system;
- Oxidation of organic compounds with photocatalytic nanoparticles is much more effective than conventional ways: COD reduction is up to 2 times faster.
- Section C-D-E - The third step of the PHOTOMEM process is a membranes process which involves three similar sections: section C ultrafiltration, section D nanofiltration and section E reverse osmosis. PHOTOMEM optimized this membrane multi-stage process which is capable to separate pollutants from up 85% of the wastewater and to reduce its COD content.
- Cleaning of the membranes - the cleaning membrane procedure is started when a pressure active control related to the membranes process is activated. To clean the surface of the membranes the clarified waters deriving by the end of the reverse osmosis and collected in tank T09 are used.
- Section F - The last step of the PHOTOMEM process is a packed column adsorption process having the aim to recover the polyphenols content inside the OMWWs and selling them to the nutraceutical/cosmetics markets for the reduction of the net cost of the treatment.
- The control system - The control system is capable to supervise each single operation of the pilot plant.
RESULTS OF WP6
The main output of the work carried out in this WP is the PHOTOMEM pilot plant located at LABOR facilities in V. Giacomo Peroni 386, 00131 Rome, Italy.
Following the P&I scheme of the process, the different steps of the treatment were implemented in the plant as follows:
1. Flocculation
Olive Mill Waste Waters (OMWWs) collected from oil mills are stored into T02. Then they are pumped into flocculation reactor R01, where the pH is adjusted by means of a peristaltic pump connected to a nitric acid solution, while they are circulating. Once the correct value of the pH is achieved the circulation is kept for 20 minutes, flocculation phase, then the circulation stops and a 23-hour sedimentation phase begins.
2. Photocatalysis
The clarified OMWWs from flocculation are stored into a intermediate storage tank T03 to allow flocculation start another run, then the first batch of waters (working volume 350L) are loaded into the photoreactor. The catalyst, the magnetic core titanium dioxide nanoparticles, is added, the air flow and the UVA lamps are switched ON and the photocatalysis starts for 4 hours.
Once ended, the photoreactor is depleted by means of a centrifuge pump which pumps the OMWWs through the magnetic trap where the nanoparticles are retained switching ON electromagnets.
The pilot photoreactor is made of:
- A tank of 0.5 m3 capacity, filled up to 350 liters, with a wooden board on the top to support the lamps, a marine propeller with 4 PVC draft tubes, each provided with a sparger, and a PVC piping air system;
- On the bottom side of the board 24 UVA lamps (each rate 30W) are mounted to irradiate the liquid surface with the UV needed for the photocatalysis;
- Four draft tubes placed inside the reactor, to reproduce the behaviour of four internal draft tube airlift reactors;
- The air inlet piping system providing air to the draft tube air lifts to generate the conditions of recirculation of the water and provide oxygen for the photocatalysis to happen: four branches each one ending in the bottom centre of each draft tube;
- A propeller placed in the centre of the reactor to help maintain the catalyst in suspension
3. Magnetic trap
The recovery of the nanoparticles is performed by means of a Plexiglas magnetic trap, in the shape of a vertical cylinder inside which a septum is placed to force the flowing of the waters, rich in nanoparticles content, in a U-shape route through the bottom of the cylinder. The magnetic trap is placed on the top of a chessboard, having square holes where up to 16 super magnets can be inserted.
4. Membrane process
The three membrane processes, UF-NF-RO, are working in series. They work in the same way, i.e.: photocatalysed OMWWs are circulated from UF tank T04 through the corresponding membrane module M01 where the concentrated is separated from the clarified waters to return into T04. Clarified waters fill the NF tank T05 and the next membrane step starts.
The only difference with filtration is that the concentrated waters deriving from UF are discharged while the ones from NF and/or RO can be redirected to section F adsorption for the recovery of polyphenols. Each membrane module contains 4 radial membranes and it is connected to its respective tank:
- Ultrafiltration (UF): 4 UF membranes inserted into UF/M01 module connected to UF/T04 tank;
- Nanofiltration (NF): 4 NF membranes inserted into NF/M02 module connected to UF/T05 tank;
- Reverse Osmosis (RO): 4 RO membranes inserted into UF/M03 module connected to UF/T06 tank.
5. Adsorption
The column feeding tank T07 collects the residues of the NF process. The residues are therefore irculated through the packed column R03 where polyphenols are trapped inside the resin filling the column. The adsorption phase lasts 3 hours and the waste is discharged switching the three-way valve V14 into right, R, position.
6. The control system
The control system of the PHOTOMEM pilot plant, as illustrated in deliverable D15, is able to supervise each single section of the process. It controls:
- Sensors: in order to read the most important process parameters in real time and step-in taking decisions according to the read values;
- Actuators: such as on-off and regulation valves to allow flow control, peristaltic, volumetric and centrifuge pumps for liquid transfer and pressurization;
RESULTS OF WP7
Two operations were performed at pilot plant lab scale: the polyphenols recovery and the post-treatment, consisting in a photocatalytic reactor, assisted by immobilized nanostructured TiO2 catalyst. This latter operation was adopted to reduce the COD content under 0,5 g/l. Chemical oxygen demand (COD) measurements were made by applying the Standard Method 5520 C. pH measurements were performed by using a Mettler Toledo EL120 instrument. Electro conductivity (EC) was measured by using a Delta Ohm HD9021r2 instrument.
During flocculation the following steps were performed:
1. addition of nitric acid solution (36% in weight) to the feedstock in order to reach a pH value equal to 3.2 in strong mixing conditions.
2. slow mixing for a period of 20 minutes, used to favour mixing.
3. Finally, flocculation takes place within the next 23 hours, during which the suspended solids - while flocculating -aggregate and give sedimentation.
The 10% of the feedstock at the bottom of the flocculation reactor is discharged and collected as mud. The remaining 90%, as clarified wastewater is sent to the next process step: Photocatalysis. The water was left to sediment for 24 hours, obtaining a well defined separation between the mud and the clarified phase. The water, as expected, results rich in solid residues. The same process of flocculation was performed on 1m3 of raw OMWWs by means of the reactor R01 of the PHOTOMEM pilot plant.
At the end of the process two samples were taken:
- one of clarified water, from the top of the flocculation reactor;
- one of muds, from the bottom of the flocculation reactor;
Again the two samples were analyzed in lab to investigate the flocculation stage performed on a huge amount of waste waters, to compare the efficiency between a laboratory scale and a pilot plant scale.
Photocatalysis was performed by using the backup photoreactor developed and described in in detail in 'paragraph 2 Section B Photocatalysis' of Deliverable D18, by using the protocol developed and described in the same document.
The tests carried out consist in:
1. addition of 2g/l of ferro-megnetic titania nanophotocatalyst to the feedstock
2. implementation of the photocatalysis for 4 hours, under the UV light (24 lamps having a total consumption of 720W with a wavelenght of 365nm) and the air supply (air flow rate equal to 200 Nm3/h)
3. Recovery of the photocatalyst through the magnetic trap described in 'paragraph 2.2 Magnetic Trap'.
4. The 100% of the feedstock is sent to the next process step, that is ultrafiltration.
Tests for Utrafiltration, Nanofiltration and Reverse Osmosis were performed by using the plant section and the protocol described in detail in 'paragraph 3 Section C-D-E Membrane processes' of Deliverable D18.
The tests on Ultrafiltration consisted in:
- separation by using 4 Desal Osmonics spiral wounded membrane modules (type GM 4040F), featuring a total membrane area of 32 m2 with a pore size about 2nm. The operating pressure was optimized during the testing phase to 4 bar, to maximize productivity without incurring in severe fouling.
Tests on Nanofiltration were performed as follow:
- separation by using 4 Desal Osmonics spiral wounded membrane modules (type DK 4040F), featuring a total membrane area of 32 m2 with a pore size about 0.2nm. The operating pressure was optimized during the testing phase to 8 bar, to maximize productivity without incurring in severe fouling.
Tests on the Reverse Osmosis were performed as follows:
-separation by using 4 Desal Osmonics spiral wounded membrane modules (type SC 4040F), featuring a total membrane area of 32 m2. The operating pressure was optimized during the testing phase to 25 bar. Fouling is not a severe issue here, therefore the minimum operating pressure capable to guarantee maximized selectivity was chosen. The recovery of the polyphenols was performed by using the protocol previously developed and described in detail in 'paragraph 4 Section F Adsoprtion' of Deliverable D18 - PHOTOMEM Pilot Plant.
- Operating mode: Polyphenol recovery was implemented according to a two-column scheme including a dephenolisation column (which rapidly saturates in polyphenols and continues to adsorb phenol long after polyphenol saturation) and a polyphenol recovery column (which adsorbs polyphenols from the dephenolised product.
- Working volume: the volume of the adsorption columns is about 0.5 L for both columns. Packing height is 10 cm for the dephenolisation column and 20 cm for the polyhenol recovery column.
- Materials: the adsorption columns is in contact with an aqueous solution during adsorption and with an ethanol solution during the desorption phase; consequently the column material requires compatibility with organic solvents. For the pilot plant, both columns are manufactured in glass.
Post-treatment
Both the organic matter content and the pH value of the RO permeate exiting the membrane process step could be, in some cases, still not within the limits to permit discharge in the municipal sewer system. In this case an additional post treatment step should be necessary to reduce the residue organic matter content and the pH value adjustment for the water disposal.
This kind of RO permeate, which may exhibit COD values smaller than 2000 mg/l and is quite transparent, may be treated again by photocatalysis, using nano-TiO2 immobilized over glass spheres as catalyst. This time, since the wastewater stream is not opaque, the irradiation with UV is more easy and efficient. Therefore, immobilized nano-TiO2 on glass spheres in a reactor may be used.
The PHOTOMEM process is effective to reduce the COD content to values in line with the limits imposed by legislation.
One of the objectives of the project is to make the initial investment of the plant and the cost of treatment acceptable, in line with the present cost of disposal for mill wastewater (which is nowadays around 30-40/m3).
Furthermore, the recovery of Polyphenols at the end of the treatment is meant to further reduce the final net cost of the overall treatment.
In this section an estimation of the investment and operational costs associated to each step of the PHOTOMEM process is reported for a plant of 40 m3/day, so as to compare them with the initial objective and to be able to evaluate with the support of the small and medium-sized entreprises (SME) working in the project and operating in the sector the attractiveness and the commercial potential of this solution for the wastewater sector.
For ease of reading, we will highlight:
i) The costs of the components of the plant that will bring to a final evaluation of the initial investment associated to a 40m3/day plant using the PHOTOMEM process;
ii) The costs of operation of the same plant for an estimation of the cost per m3 of OMWW treated.
The indicators identified at the beginning of the project showed a cost of less than 300.000 EUROS for the 40m3/day plant (investment), and a cost of operation reduced respect to the current 40 EUROS/m3 estimated for the existing technologies and disposal treatments.
Total cost per day
The estimation of the costs of operation of the plant comes as a consequence from the values reported above. The depreciation over the 15 years hypothesized for the plant itself has been calculated accordingly.
The parameters used for this estimation are the following:
1) The days of operation along one year (estimated: 135 days);
2) The hours of operation of the plant in one year (135 days x 24 hours a day = 3.240);
3) The capacity of the plant, 40 m3 treated per day;
4) The cost of chemicals;
5) The cost of electricity;
6) The personnel costs;
7) The daily depreciation cost including the maintenance cost;
The estimated cost of operation is of the order of 60 EUROS/m3, which is slightly higher than current treatments (40-50 EUROS/m3) However, the cost can be optimized with the following measures:
- recovery of polyphenols which are added value products which can have an outstanding market value (refer to the following paragraph)
- reduction of the membrane size and operating pressure, reducing the installation, maintenance and operational costs. This aspect is considered to be feasible due to the presence of the pretreatment realized by flocculation and photocatalysis. A centrifuge could be included in the plant to reduce the charge experienced by the membranes.
- reduction of the cost of the MAG TiO2 nanocatalyist for the operation, which represents the most relevant share of the cost of operation.
This can be achieved by:
a. optimization of the production costs of the Nanoparticles
improvement of the regeneration of the nanocatalysts. The number of batches after which the nanocatalyst cannot be regenerated, now estimated to be 8, should be verified in detail with further tests. Also a stronger regeneration process could be studied and assessed. In case it would be verified the possibility to regenerate the nanocatalyst for 12 cycles (3 days) the cost of the nanocatalyst would be reduced of 33% and the total cost of the OMWW treatment would be reduced to 46 /m3.
Conclusions
Following the results of the tests carried out on OMWW collected from an Italian olive mill near Rome, it is evident that:
- 75.3% of the initial raw OMWW was obtained as purified wastewater solution to discharge into a municipal sewer system.
- The photocatalysis assisted by the developed magnetic core TiO2 catalyst was quite effective, leading to a COD reduction of 35 %.
- The magnetic trap was able to recover 96% of the magnetic photocatalyst.
- The separation by membrane processes exhibit an overall effectiveness as expected, however the separation by NF was better than predicted, whereas the RO underperformed.
- In order to get the COD target of 500 mg/l a post-treatment based on photo-catalysis assisted by immobilized nanostructured TiO2 was applied. This operation not considered in the proposal, was developed during the project.
- The process recovery of polyphenols represented the hardest task to be achieved, because of the presence in the OMWW of phenols which was unpredicted at the time of the proposal submission. The presence of phenol fostered a process development based on a two stages adsorption.
An economic evaluation of the investment and operation costs of the PHOTOMEM plant scaled up to a common treatment capacity for a medium olive mill (40m3 of WW treated per day) was performed. As it can be seen from the results of such analysis:
a) The target of the 300.000 EUROS investment for the plant was achieved: from the costs of equipment and accessories for assembling the plant it is evident that a major part of the investment is due to the necessity to have a high number of modules for the membrane stage, which represents a core step in the purification process of the plant. High costs are also associated to the purchase of the tanks and reactors for the treatment, to the electric wiring and cabling, to the start up phase of the plant and to the use of valves and UV lamps.
b) The target of reducing the operation costs respect to the current estimation of 40/m3 has been exceeded: in fact, this initial requirement has not been reduced. This refers to a mean value for the treatment of olive mill wastewaters with other techniques respect to the ones constituting the PHOTOMEM technology. This one makes great use of chemicals and of a catalyst for the photocatalytic step which, even for high production quantities, remains quite an expensive consumable.
RESULTS OF WP8
In this WP, two important documents summarizing the intentions of the partner small and medium-sized entreprises (SME)s in the Consortium to disseminate and exploit PHOTOMEM results were produced: the first is the Interim Plan for Use and Dissemination of Foreground, and the second is the final version of this deliverable, the Final PUDF, completed with the latest considerations on the achieved results and on the basis of the performances obtained during the field tests on the plant. We hereby summarize the main results that this WP produced in the whole project duration.
Public Deliverables and Brochures
The partner small and medium-sized entreprises (SME)s specifically requested and arranged to have 3 different materials for dissemination:
- Brochure for dissemination purposes,
- Brochure with technical aspects of the project,
- The project poster
The reason for this choice is mainly due to the intention, of the project partners, to differentiate the tool to be used with the target audience; in particular:
- The brochure for dissemination is intended as an immediate and communicative material, that can be spread to any type of public, not specifically expert in technological fields or in the sector addressed by the PHOTOMEM project. This material can reach any type of public, and proves easy to read, rich in bullet points summarizing the objectives and the results expected from the research, and highlighting the improvements that this innovative treatment aims at providing to the wastewater market sector in the reference countries and in Europe.
Furthermore, to reach a wider audience and with the purpose of allowing the beneficiary small and medium-sized entreprises (SME)s to reach any of their already ongoing contacts with dedicated materials, the partners also arranged for a translation of these brochures into the Consortium languages, in particular:
- ECS translated into Italian the 2 brochures,
- MT translated them into French,
- BIOAZUL translated them into Spanish, and
- FRA translated the brochures into Greek,
- The technical brochure is intended as a more detailed description regarding the research leading to the PHOTOMEM project results, thus represents an optimal tool to be diffused among the technical staff of the existing wastewater plants, either technicians or plant responsible; this brochure shows the different steps of the process, going into detail of each of them. It therefore supports the communication with the expert audience, to whom the specifications and the layout of the overall process can be described accurately.
- A dedicated, specific dissemination material of immediate impact, especially when participating to national or international events of relevance in the industrial wastewater sector , is the project poster. In fact, it can be used for several purposes, when organizing seminars or dedicated speeches to the target audience, or when taking part to fairs or exhibitions to show the innovation behind the project.
Newsletter and Contacts
In order for the project to be duly disseminated to a representative group of companies belonging to this type of audience, the project partners, and the small and medium-sized entreprises (SME)s in particular, identified, thanks to their networks and already established contacts, a list of potentially interested small and medium-sized entreprises (SME)s to be involved in the diffusion of news about PHOTOMEM. The main tool used for these contacts was the newsletter via mailing. Appendix II of the PUDF Deliverable reports the list of companies were these updates regarding the project developments were sent. This list has been updated with some other companies through the second period of the project.
As a general rule, each small and medium-sized entreprises (SME) in the Consortium sent a newsletter to the companies listed for their reference countries, so that:
- ECS promotionally emailed the Italian companies involved in the OMWW treatment or oil production in the region of Rome (Lazio),
- BIOAZUL contacted via email the Spanish companies,
- MT the French ones, and
- FRA the Greek ones.
Particular attention was given, by the Technical Manager, in the person of Prof. Angelo Chianese from UNIRO (University of Rome 'La Sapienza' Department of Chemical Engineering) to keeping the contacts with a big player in the market of olive oil production in Italy, Oleifici Mataluni - http://www.oleificimataluni.com/oliodante/.
Events and training to the small and medium-sized entreprises (SME)
As for the participation to events in the wastewater treatment sector, relevant respect to the project scope and technological objectives, demonstration events, as initially planned in the interim PUDF were not possible, due to the assessed delays in the finalization of the pilot plant and the tests sessions necessary for the fulfillment of a proper assessment of the results.
Patent and publication search
Respect to the original patent and publications search performed in the Interim Plan for use and dissemination of foreground deliverable, we now selected only the most relevant ones, having a certain connection to the results developed in PHOTOMEM. This research was of support in the definition of the exploitation strategy, which was intended in the project as a way to take advantage of a new treatment technology, on which no direct application or commercialised product has already been found on the market.
Exploitation Strategy and IPR Management
The concrete output of the IPR Management tasks was the definition of an agreed strategy for the exploitation of the obtained results. The PUDF reports the degree of completion of each specific result of the project, with the missing steps for their commercialization, and the exploitation intention of the owners for the future.
The output of such discussions led to the identification of the following points for the exploitation plan to be adopted by the SMEs for the plant commercialization and exploitation:
1) The photocatalytic reactor developed in the project cannot be exploited as a stand-by result, especially in case of an application for a patent;
2) The production process for the ferromagnetic nanoparticles, owned by the French SME Marion Technologies should not be patented alone, as patenting a process might not be successful if not related to a specific application;
3) The PHOTOMEM plant, because of its commercial potential, will be object of exploitation by the owning partners, ECS and BIOAZUL, and thus patents will not be sought after for this result.
On the basis of these considerations, the partners decided what follows:
The only attractive solution, for the enterprises owning the project results, for the protection of the knowledge generated in the project, is to unify at least 2 results of the project to apply for a patent covering several aspects of the treatment process. In particular, the best option for the protection of the IPs coming from the PHOTOMEM research was considered to be the application for a patent including the design of the photocatalytic reactor using dispersed photocatalytic ferromagnetic titania nanoparticles for the treatment of high COD wastewater.
This strategy would therefore include:
i) The use of result no. 1 - that is, the photocatalytic ferromagnetic titania nanoparticles produced by ARMINES and MT,
ii) The use of part of result no. 2 that is, the procedure outlined for photocatalysis, which represents one of the steps of the overall PHOTOMEM treatment, and
iii) The use of part of result no. 3 that is, the photocatalytic reactor allowing for further reduction of COD contents in the olive wastewater with respect to the traditional techniques.
According to this choice, the intention of the beneficiaries owning this result BIOAZUL, ECOSYSTEMS and MT - is that of performing a deep analysis of the photocatalytic treatment in terms of COD reduction, and to eventually decide to apply for a patent which considers the specific application of photocatalysis, via a photocatalytic reactor with dispersed photocatalytic nanotitania particles, to the treatment of high COD waste water.
In summary, the exploitation strategy for each of the beneficiaries can be outlined:
- ECS , MT and BIOAZUL intend to jointly:
1) Study and evaluate the possibility to patent the photocatalytic reactor with dispersed nanotitania for treatment of high COD content wastewater on the basis of the tests assessment and on the performances of photocatalysis in reducing the organic content in the olive wastewater;
MT intends to:
1) Act as exclusive producer of the ferromagnetic nanoparticles for the PHOTOMEM and other plants installed by ECS and BIOAZUL (and their licensees), provided that:
- they furnish the nanotitania for PHOTOMEM plants at a market value,
- the particles are produced in the respect of the quality standards required for the process.
2) Modify or apply the production process to any other application or for producing other materials;
FRA intends to:
1) Exercise an exclusivity option for the use of PHOTOMEM in Crete for 2 years after the end of the project;
2) Request to have the pilot plant at his facilities after the end of the project, or to have a new plant (at own costs);
ECS and BIOAZUL intend to:
1) Commercialize the PHOTOMEM plant in their countries (Spain and Italy);
2) Use the plant in other WW treatments and to license the results to third parties;
3) Jointly look for a licensee of PHOTOMEM plant in other markets.
On the base of the evaluation of how to proceed with the exploitation actions mentioned above, the PHOTOMEM beneficiaries co-owning results of the project will develop a Joint Ownership Agreement.
Potential Impact:
Each of the participating small and medium-sized entreprises (SME) in the Consortium will receive great benefits and gain competitive advantage by owning the project results as they have been agreed and shared, in relation to each partner's business line.
In fact:
- the proposer SMEs, ECS and BIOAZUL, specialized in the wastewater treatment plants design and construction will strongly benefit from the possibility to sell the PHOTOMEM wastewater treatment plant in 2 different countries (Italy and Spain).
- On the other hand, the producer of custom-made ceramic powders and nanostructured materials for industrial use (MT) intends to produce and provide the ferromagnetic photocatalytic titania nanoparticles.
- Finally, the end-user FRA (Greece) will apply the technology in its production site and will contribute to validate the purification process.
We believe the market potential for such a solution would be of the order of several tens of millions of Euro. The tangible outcomes of the PHOTOMEM project, available to small and medium-sized entreprises (SME) partners for exploitation will be:
1) Production process for ferromagnetic photocatalytic titania nanoparticles
2) Economical wastewater treatment for OMWW based on photocatalytic pretreatment, membrane filtration and polyphenols recovery
3) PHOTOMEM pilot plant of 1 m3/day capacity to validate the OMWW treatment.
The attached file to this report shows a table indicating:
- For each result, the SMEs proposers who are going to have a main role in the exploitation, and the RTD performer who are providing research services,
- Competences and role of the SMEs and RTD performers
List of Websites:
http://www.photomem.eu/.
