Anaerobic Biodigester at Surrey Docks farm
We have our very own Anaerobic Biodigester onsite at the farm. The biodigester was installed in a collaborative project between the farm and the Environmental Systems Engineering / Engineering for International Development department of UCL.
The Background, Objectives and Specific outputs of the project as laid out by Dr. Ilan Adler of UCL are detailed here. If you would like to take a closer look at our Biodigester or know more about the project please get in touch with James or Hugh. Details can be found on the contact us page.
- Anaerobic digestion (AD) is a promising technology for farmers to use their organic waste products to generate valuable biogas (used as fuel) and high quality liquid fertiliser (biol). It relies on anaerobic, heat-producing, bacteria inside a reactor.
- Sistema Biobolsa is a Mexican social enterprise, an offshoot from IRRI-Mexico (www.irrimexico.org), which is an NGO with ample experience in community-based biogas projects. They developed a unique and cost-effective biodigester solution which has been successfully installed all over Mexico and in other parts of Latin America (www.sistemabiobolsa.com)
- UCL secured funding in 2013 through the grand challenges scheme to install the first Sistema Biobolsa digester in Europe, at Surrey Docks, an urban farm located along the Thames in East London. The system is now fully operational, and currently uses a small fraction of the animal waste generated in the farm to heat water. The effluent is currently sprayed on compost piles to accelerate its degradation, enrich the soil and, as a new experimental feature, to release additional heat inside a greenhouse.
- The project was designed and implemented by 4th year MEng students starting in 2013, in parallel to a collaborative project. Initial operation of the Biobolsa was closely monitored by an MSc project in the summer of 2014, and by two subsequent 6 month undergraduate projects. These reports will all be available to you as part of this project.
The main aim of this collaborative project is to find optimal ways in which to treat and reuse the relatively large volumes of effluent which are currently generated by the Biodigester. This will include looking into compost acceleration, pasteurisation (i.e. using a combination of solar energy and biogas), as well as testing a novel technique for nutrient recovery and disinfection developed by the University of Beja in Portugal. Business ideas related to the marketing of this liquid fertiliser (biol) are also expected, along with studies as to the quality of the product, and the treatment required to bring it up to a market standard.
- Design an experimental plan to sample the biol from the pilot project, comparing with previous studies, analysing for nutrients, microorganisms and other quality characteristics.
- Refine the ‘cost-benefit calculator’ developed by previous CESP students, which will help the farm get better estimates of gas production, fertiliser, marketing value, etc.
- Investigate ways in which the fertiliser could be treated to comply with regulations, health and safety aspects.
- Develop a social feasibility study around acceptance of farmers, policy, regulation and subsidies for farmers.
- Test (in the lab and in the field) and design the optimal application system of the lime/precipitation technique developed by the University of Beja.
- Outline business model for the farm, comparing the different options for fertiliser reuse available, as well as looking into the fertiliser market to analyse competing options, etc.