New membranes and integrated hybrid membrane systems for VOCS removal from industrial contaminated water

Project Information

NISIW

Grant agreement ID: IC15980140

Project closed

Start date 1 December 1998

End date 31 May 2002

Funded under

• Specific research, technological development and demonstration programme in the field of cooperation with third countries and international organizations, 1994-1998

Total cost

No data

EU contribution

No data

Coordinated by

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE
France

CORDIS provides links to public deliverables and publications of HORIZON projects.

Links to deliverables and publications from FP7 projects, as well as links to some specific result types such as dataset and software, are dynamically retrieved from OpenAIRE .

Deliverables

New PTMSP based disk-type membrane module for VOC recovery from gaseous streams

Based on polytrimethylsilylpropyne (PTMSP) prepared with Nb-catalyst, physical coating of thin PTMSP films (obtained from solution) was developed on porous stainless steel support with pore size about 3-5 microns providing disk type elements. This coating procedure was carried out under lab dust-free conditions with using particular glassy flat sheet and particular knife to provide thin dense layers with film dimensions suitable for membrane elements preparation. It was shown that for long-life operating, the thickness of PTMSP films about 10 microns was needed. Air permeability testing experiments showed that all prepared films were defect-free. The stainless steel porous supports (about 45 disks) were specially prepared for disk-type module. These supports consist of three disk-type layers with central hole: two external layers based on sheets and one net with cells about 1mm introduced in between. The prepared disks were physically coated with PTMSP thin films through pre-fixation step and dried under air during two days. This technique provides a good permeation stability of composite membrane and module. The permeability rate of each element was found to be in good agreement with expected values (Flux of N2 about 200l/m²hbar) and O2/N2 selectivity mainly upper than 1.5 (mainly about 1.7-2.0). This membrane block module had a membrane area of about 0.75m².

Transport parameters of VOCs' selective polymer films based on phosphazene, siloxane or propene backbones for industrial water treatment by membrane processes

Polymer film transport parameters for three VOCs, dimethylketone (DMK), dichloromethane (DiCl), toluene (Tol), and for water were determined by isothermal sorption and gas/vapour permeability. The critical role of the activity range as well as the temperature dependence were clearly identified and quantified to optimise separation parameters for VOCs for either water-organic vapours or inert gas-organics mixtures. Polyorganofluorophosphazene (PTFEP) exhibits a marked endothermic sorption for DiCl (Eac=22kJ/mole, S=0.7cm³ (STP)/cm³cm²Hg at 20°C) whereas for DMK (S=2.5) and Tol. (S=0.2) exothermic sorptions were recorded. PTFEP permeabilities for N2, H(2)O, DMK, DiCl and Tol are respectively in barrers 32, 16000, 13800, 600 and 700. Copolysiloxaneurea (BPDMS) exhibits a marked exothermic sorption for DiCl (Eac=-11kJ/mole, S= 4cm³ (STP)/cm³cm²Hg at 20°C) whereas for DMK (S=0.3) and Tol.(0.8) the sorptions are thermally activated. BPDMS permeabilities for N2, H(2)O, DMK, DiCl and Tol are respectively in barrers 310, 38000, 27000, 210000 and 63500. Polytrimethylsilylpropyne (PTMSP) exhibits a marked exothermic sorption for Tol (Eac=-20kJ/mole, S= 6.6cm³ (STP)/cm³cm²Hg at 20°C) whereas sorptions for DMK (S=1.3) and DiCl (S=1.4) are thermally activated. PTMSP permeabilities for N2, H(2)O, DMK, DiCl and Tol are respectively in barrers 4000, 38000, 172000, 900000 and 275000.

New hybrid membrane process of lower energy consuming wastewater treatment of closed re-circulating type with VOCs recovery based on new polymeric membranes

The new hybrid membrane process designed to recover VOCs from industrial water was based on a single membrane stage of closed type implementation on a stripper unit. The membrane part of this hybrid system was constituted of a membrane module having of surface area of 0.75m², the active dense layer being prepared from PTMSP polymer produced under pilot scale production, i.e. with a cost estimated as 200 Euro per kg corresponding to 30-50m² of active layer. Connected to a wastewater model containing Toluene or Dichloromethane, this system was operated during 4 months (day-time) as a pilot unit to treat about 1m³ per day with gas flux up to 800Nl/h with low VOC concentration, i.e. 0.2-0.6 vol.%; the rate of membrane VOC recovery was about 150g/day for toluene and 100g/day for dichloromethane. The results of experiments were in good agreement with calculated ones. For producing of 100m³ of recycling water per day with VOC recovery (e.g. 15l toluene or 10l dichloromethane per day) the separating hybrid system would require 20 membrane modules of 4m²; such a membrane block will have dimensions 80x80x90cm (very compact) and could be installed in line of traditional strippers. Since VOC recovery takes place from vapour phase there is no problem for scaling up procedure. It was calculated that if the hybrid system will operate during at least two years the developed system should return money at least from solvent recovery point in the range of studied initial concentrations.