Biomethane innovation: the CAP for research into methane produced from sewage

BIOMETHANE FOR TRANSPORT –

In Milan, CAP Holding has started experimentation with the support of the CNR to use – after treatment – ​​the residual sludge from the classic biological purification system as an alternative fuel in the transport sector.The research, which involves the collaboration of the FCA group, aims to replace the fuels currently used and evaluate the impact of biogas on the environment, specifically the atmosphere. Simultaneously, it is conducting studies with the company Agrosistemi to test fertilizer from liquid biological sludge.

ALSO READ: Renewable energy: In Germany, a municipality runs on wind, solar, and biogas alone.

CAP HOLDING –

The CAP Holding group manages the water supply, sewerage, and wastewater treatment systems of the Metropolitan City of Milan. Adopting a circular economy approach has allowed the company to: identify sewage waste as a new source of energy supply as an alternative to fossil fuels. In fact, through sector research, it was possible to find an alternative fuel: biomethane. It is a gas containing at least 95% methane and produced from renewable sources. It is produced using gas generated by the anaerobic digestion of biomass in a controlled environment (digester) or in a landfill, following the decomposition of waste, or from gas resulting from the gasification of biomass. Subjected to a purification and upgrading process, it reaches the quality of natural gas and, respecting the chemical-physical characteristics foreseen in the AEEGSI directives, it is suitable for the subsequent compression phase for injection into the natural gas network.

THE POTENTIAL OF BIOMETHANE IN THE TRANSPORT SECTOR –

Studies into the development of biomethane as a fuel were conducted at the Niguarda-Bresso sewage treatment plant, built in the 80s and activated in 1991. It is capable of collecting wastewater from the municipalities of Besso, Cinisello, Balsamo, Cormano, Cusano Milanino, and Paderno Dugnano and has been estimated to be capable of generating an annual production of 341.640 kg of biomethane. This quantity is sufficient to power 416 vehicles for 20 kilometers per year, corresponding to a total of 8.320.000 kilometers. That is, more than 200 times the circumference of the Earth. The production cost (€0,58/kg) is significantly lower than the cost of imported methane (€0,9/kg).  The advantages of biomethane are therefore numerous. In the first place, is capable of counteracting climate changeThe released methane would be able to balance the gaseous composition of the atmosphere, limiting the greenhouse effect. This environmental motivation is followed by a strategic one, given that Italy is the world's second largest importer of natural gas. privileging the consumption of biomethane would increase the number of economic resources availableA further consideration is added, which concerns the production sector. In our system, sewage is constantly generated, so it is worth asking the question of how to exploit this raw product.Unlike wind and photovoltaic energy, biogas and biomethane, precisely because of this intrinsic property, allow for greater reliability in energy planning.

THE FERTILIZER –

For the development of the defecation calcium carbonate fertilizer, trials were conducted at the Cassano d'Adda wastewater treatment plant, starting with the liquid biological sludge produced by the Cassano and Settala wastewater treatment plants. The research involved recovering and feeding the liquid biological materials to a chemical reactor, alkaline conditioning of the starting biological material, and subsequent neutralization with sulfuric acid or carbon dioxide and dehydration of the liquid biological material. From a commercial perspective, the CAP Group collaborated with the VOMM Group, leveraging its support, technologies, and expertise for drying and pelletizing, with the goal of transforming the sludge into a baggable fertilizer for potential mass distribution.

The project is competing for the 2016 edition of the Non Sprecare Award. To learn more about the competition and participate, go to here!

If you liked the project, share it on Facebook, Twitter, and G+!

TO KNOW MORE:A London public bus runs on excrement (Video)