This service provides three different solutions for the valorisation of bio waste for biogas production. Each technology can be sold or leased to the users.
The first solution (7a) is based on the joint treatment of blackwater and grinded bio waste at building (pilot) scale for wet anaerobic digestion using AnMBR solution. The solution foresees the recovery of >95% food waste and >95% organic matter from blackwater. This may lead to:
- >90% treated blackwater reuse for toilet or fertigation.
- renewable energy from biogas (linked to S7c).
- compost (linked to S8) at home level for use by dwellers, neighbours or use in public gardens.
In HOUSEFUL, an innovative AnMBR system for the joint treatment of blackwater and grinded BW will be designed and constructed at laboratory and pilot scale as a compact and transportable unit. The design will be addressed for a minor odour production. The systems will be started up and optimised using real wastewater and grinded bio-waste effluents. Biogas will be treated using absorption technologies (Solution S7c) ensuring a biogas quality corresponding to natural gas grid specification for potential grid injection, use in μCHP, combustion in a natural gas boiler or other valorisation routes proposed by stakeholders. Once safety of the system is ensured, the system will be emptied and transported in a container for final integration in Demo 1 in operational environment at pre-commercial scale. The biogas conversion system will be initially dimensioned for the renewable energy recovery of 2600 kWh/y from biogas.
The second solution (7b) uses the solid fraction of wastewater together with grinded biowaste to produce biogas and compost using a dry anaerobic digester. The anaerobic digestion will happen below the ground while the biogas produced will be stored above the ground. After separation of the un-segregated WW in Demo 3, the solid fraction and grinded BW can be mixed and used for production of biogas and compost using a dry anaerobic digester. Goals foreseen by these solutions include the minimum recovery >95% food waste and >95% organic matter from solid fraction of WW for production of renewable energy from biogas (linked to S7c) and compost (linked to S8) at home level. HOMEBIOGAS system will be adapted for biogas and compost production from BW or manure to the new feed. To make the existing system to work autonomously, some modifications like a feed slide need to take place. The sludge at the bottom of the anaerobic digester can be emptied regularly (once every 6 months), to produce high-quality compost.
The last solution (7c) complements the two core AD technologies developed in HOUSEFUL for the treatment of blackwater and BW at building scale. This is focused on the development of absorption technologies for ensuring a biogas quality corresponding to natural gas grid specification for potential grid injection, use in µCHP, combustion in a natural gas boiler or other valorisation routes proposed by stakeholders.
The solution will also include the cleaning of biogas for increase of CH4 content (>80%) and potential storage in inflatable and impermeable fabrics. This energy storage can be further used for potential grid injection, use in µCHP, or combustion in a natural gas boiler and can support the NZEB or even passive house claim to reach full autonomy (100%) even in winter times (December-February), when heating systems are mostly needed, and sun heating will not be easily available.
In case of an ´in situ´ storage for a long time period (for example to use in winter the biogas generated in the warm seasons), upgraded biogas could be storage in gas bottles at 200 bar. In this case, a compression system should be required an specific safety measures should be taken according local/national legislation. Also an extracost for the compression stage has to be taken into consideration.
In terms of biogas uses, service 7c could be adapted to fit with energy, cogeneration or accumulation requirements of buildings. On balance, a flexible service is provided.
