Periodic Reporting for period 1 - MicroAlgae 4.0 (Microalgae cultivation in a WRRF scheme to improve circularity and risk-based assurance in wastewater treatment using digital tools.)
Reporting period: 2022-09-01 to 2024-08-31
MicroAlgae 4.0 is a research and career development project that aims to develop a Water Resource and Recovery Facility (WRRF) scheme based on microalgae cultivation biotechnology to maximise reclaimed water production and nutrient recovery from wastewater, produce by-products from microalgae biomass, and to minimise environmental pollution. To this aim, MicroAlgae 4.0 will focus on overcoming the barriers that hinder the wide implementation of microalgae-based systems by improving the performance and reliability of the process, developing innovative digital tools that monitor and automate the system, and assuring the safety of the by-products obtained.
MicroAlgae 4.0 follows some principles recognised in the European Green Deal, specifically: i) Circular Economy (CE) principles; ii) safety in reclaimed water and nutrient management; iii) digitalisation; iv) water-energy-food-ecosystems (WEFE) Nexus approach; and v) the zero-pollution ambition. Microalgae cultivation biotechnology appears as one of the main approaches to develop CE in the water and waste sectors due to their capacity to recover nutrients from wastewater. Microalgae present other advantages: act as carbon sink, valuable biomass can be obtained, can grow in non-arable lands, can be cultivated in different wastewater streams and are capable of oxidising pollutants of emerging concern (photocatalysis). Previous studies on microalgae-based wastewater treatment have mainly focused on design factors and on the removal of organic matter, solids and nutrients. However, wide implementation of microalgae technology in WRRF schemes is still lacking, mainly due to: i) the difficulty to reach and maintain steady state (due to variable conditions and the proliferation of competing organisms); ii) poor monitoring and automation which usually entails high operating costs; iii) scarce information related to the removal emerging pollutants (pharmaceuticals, endocrine disruptors, microplastics, metals); iv) legal, political and social barriers in the application of CE; v) lack of information in terms of possible risks in the use of reclaimed water and nutrients in agriculture. MicroAlgae 4.0 tries to overcome these barriers and go beyond the current state-of-the-art due to its innovative approach and the alignment with current European policies.
The knowledge, techniques and digital tools developed in MicroAlgae 4.0 are achieved by pursueing the following objectives:
- To implement microalgae cultivation technology to maximise the recovery of reclaimed water, nutrients, and energy from urban wastewater in a WRRF scheme.
- To assess and manage the developed microalgae-based WRRF scheme to ensure the economic and environmental feasibility and safety in a Circular Economy approach.
- To simulate, model and develop ICA systems for the microalgae cultivation system evaluated to improve the reliability and feasibility of the microalgae cultivation system.
By achieving these objectives, it is expected that:
i) the reliability and stability of the microalgae cultivation process improve, since outdoor cultivation systems are rarely continuously operated in the long term (time scale of years);
ii) the development of digital tools for microalgae-based systems help to maximise resource recovery. This is a promising and scarcely developed topic in this kind of systems;
iii) data and information concerning safe water reuse from microalgae-based systems is increased. Most of microalgae systems studied so far focus on the recovery of the microalgae biomass, but scarce information can be found about water reuse and nutrient management.
MicroAlgae 4.0 follows some principles recognised in the European Green Deal, specifically: i) Circular Economy (CE) principles; ii) safety in reclaimed water and nutrient management; iii) digitalisation; iv) water-energy-food-ecosystems (WEFE) Nexus approach; and v) the zero-pollution ambition. Microalgae cultivation biotechnology appears as one of the main approaches to develop CE in the water and waste sectors due to their capacity to recover nutrients from wastewater. Microalgae present other advantages: act as carbon sink, valuable biomass can be obtained, can grow in non-arable lands, can be cultivated in different wastewater streams and are capable of oxidising pollutants of emerging concern (photocatalysis). Previous studies on microalgae-based wastewater treatment have mainly focused on design factors and on the removal of organic matter, solids and nutrients. However, wide implementation of microalgae technology in WRRF schemes is still lacking, mainly due to: i) the difficulty to reach and maintain steady state (due to variable conditions and the proliferation of competing organisms); ii) poor monitoring and automation which usually entails high operating costs; iii) scarce information related to the removal emerging pollutants (pharmaceuticals, endocrine disruptors, microplastics, metals); iv) legal, political and social barriers in the application of CE; v) lack of information in terms of possible risks in the use of reclaimed water and nutrients in agriculture. MicroAlgae 4.0 tries to overcome these barriers and go beyond the current state-of-the-art due to its innovative approach and the alignment with current European policies.
The knowledge, techniques and digital tools developed in MicroAlgae 4.0 are achieved by pursueing the following objectives:
- To implement microalgae cultivation technology to maximise the recovery of reclaimed water, nutrients, and energy from urban wastewater in a WRRF scheme.
- To assess and manage the developed microalgae-based WRRF scheme to ensure the economic and environmental feasibility and safety in a Circular Economy approach.
- To simulate, model and develop ICA systems for the microalgae cultivation system evaluated to improve the reliability and feasibility of the microalgae cultivation system.
By achieving these objectives, it is expected that:
i) the reliability and stability of the microalgae cultivation process improve, since outdoor cultivation systems are rarely continuously operated in the long term (time scale of years);
ii) the development of digital tools for microalgae-based systems help to maximise resource recovery. This is a promising and scarcely developed topic in this kind of systems;
iii) data and information concerning safe water reuse from microalgae-based systems is increased. Most of microalgae systems studied so far focus on the recovery of the microalgae biomass, but scarce information can be found about water reuse and nutrient management.
- Design and construction of a pilot microalgae system which was integrated to conventional wastewater treatment process based on activated sludge. This approach could facilitate its industrial implementation, as activated sludge systems are widely implemented (especially at large scale), so that their total substitution by microalgae systems would imply very high economic investment in infrastructure.
- The year-long operation provides useful knowledge on the behaviour that the system would have along the year, thus leading to more accurate assessment.
- The methodologies implemented in this study: risk assessment, Nexus assessment, are relatively easy to replicate in similar studies, projects or processes.
- The results of the project have high applicability to industrial scale and for the commercialisation of the by-products as the project was developed with this approach. Proof of that is the evaluation of legal requirements of by-products, comprehensive evaluation of impacts and/or benefits of the process, etc.
- Digitalisation based on machine learning techniques to improve the control and prediction of the microalgae cultivation system.
- Evaluation of the current legislation on the use of circular by-products and gaps analysis.
- Training activities on: upscaling of industrial water and waste treatment systems, with special focus on microalgae biotechnology; modelling of microalgae cultivation; machine learning techniques for data analysis and control of the microalgae cultivation process; alternative assessment methodologies; project management, advanced analyses for the evaluation of microalgae properties and emerging pollutants; agronomic indicators to evaluate the biofertilising capacity of microalgae biomass; proposal writing.
- The year-long operation provides useful knowledge on the behaviour that the system would have along the year, thus leading to more accurate assessment.
- The methodologies implemented in this study: risk assessment, Nexus assessment, are relatively easy to replicate in similar studies, projects or processes.
- The results of the project have high applicability to industrial scale and for the commercialisation of the by-products as the project was developed with this approach. Proof of that is the evaluation of legal requirements of by-products, comprehensive evaluation of impacts and/or benefits of the process, etc.
- Digitalisation based on machine learning techniques to improve the control and prediction of the microalgae cultivation system.
- Evaluation of the current legislation on the use of circular by-products and gaps analysis.
- Training activities on: upscaling of industrial water and waste treatment systems, with special focus on microalgae biotechnology; modelling of microalgae cultivation; machine learning techniques for data analysis and control of the microalgae cultivation process; alternative assessment methodologies; project management, advanced analyses for the evaluation of microalgae properties and emerging pollutants; agronomic indicators to evaluate the biofertilising capacity of microalgae biomass; proposal writing.
MicroAlgae 4.0 project has advanced quite significantly the state-of-the-art in comparison to the beginning of the project. The main advances have been reached in the following topics:
- Experimental data on the assessment of the most appropriate microalgae cultivation media obtained by combining sewage streams. This aspect was unclear in the literature as it was normally assessed qualitatively rather than using experimental data.
- Experimental data on the operation of microalgae cultivation system at demonstrative scale and outdoor conditions for one year.
- Multi-criteria analysis of data produced during the continuous operation of microalgae cultivation system.
- Results on the evaluation of the microalgae cultivation system according to biorefinery approach, i.e. considering the integrated system as a producer of by-products (reclaimed water and microalgae biomass) from wastewater, rather than focusing on wastewater treatment only (conventional approach).
- Evaluation (experimental and/or theoretical) of potential uses of the microalgae biomass, i.e. biofertilisers, biostimulants, biogas, biochar.
- Results on the comprehensive evaluation of the system using not only techno-economic assessment, but also more complex methodologies such as Nexus assessment.
- Risk analysis of the by-products obtained, including the development of standard methodology for its implementation.
- Knowledge regarding the development of scientific-based models and predictive control system for improving the long-term operation of the system. Current studies generally lack practical application of these techniques for operating microalgae systems.
- The pilot-scale microalgae system of this project is expected to be the starting point of other EU-funded projects where the coordinator is involved, i.e. HE-CARDIMED and HE-SEACURE, which also use microalgae cultivation system to treat diverse wastewater streams.
- Results of the survey has help to detect certain gaps in the knowledge of university students regarding sustainability and circular economy issues.
- Use of fluorescence-based parameters to evaluate microalgae performance. These parameters can serve as indicators of microalgae performance, but are rarely used in water treatment systems.
- Improvement of respirometric methodology to evaluate simultaneously the activity of microalgae, ammonium oxidising, nitrite oxidising and heterotrophic bacteria. Respirometric methodologies normally focus on specific groups of organisms.
- Microalgae biomass showed good characteristics for sustainable biochar production, although their high water content is significant drawback.
- Experimental data on the assessment of the most appropriate microalgae cultivation media obtained by combining sewage streams. This aspect was unclear in the literature as it was normally assessed qualitatively rather than using experimental data.
- Experimental data on the operation of microalgae cultivation system at demonstrative scale and outdoor conditions for one year.
- Multi-criteria analysis of data produced during the continuous operation of microalgae cultivation system.
- Results on the evaluation of the microalgae cultivation system according to biorefinery approach, i.e. considering the integrated system as a producer of by-products (reclaimed water and microalgae biomass) from wastewater, rather than focusing on wastewater treatment only (conventional approach).
- Evaluation (experimental and/or theoretical) of potential uses of the microalgae biomass, i.e. biofertilisers, biostimulants, biogas, biochar.
- Results on the comprehensive evaluation of the system using not only techno-economic assessment, but also more complex methodologies such as Nexus assessment.
- Risk analysis of the by-products obtained, including the development of standard methodology for its implementation.
- Knowledge regarding the development of scientific-based models and predictive control system for improving the long-term operation of the system. Current studies generally lack practical application of these techniques for operating microalgae systems.
- The pilot-scale microalgae system of this project is expected to be the starting point of other EU-funded projects where the coordinator is involved, i.e. HE-CARDIMED and HE-SEACURE, which also use microalgae cultivation system to treat diverse wastewater streams.
- Results of the survey has help to detect certain gaps in the knowledge of university students regarding sustainability and circular economy issues.
- Use of fluorescence-based parameters to evaluate microalgae performance. These parameters can serve as indicators of microalgae performance, but are rarely used in water treatment systems.
- Improvement of respirometric methodology to evaluate simultaneously the activity of microalgae, ammonium oxidising, nitrite oxidising and heterotrophic bacteria. Respirometric methodologies normally focus on specific groups of organisms.
- Microalgae biomass showed good characteristics for sustainable biochar production, although their high water content is significant drawback.