Sustainable management of biogas produced with an anaerobic digestion plant

There are several ways to use biogas from anaerobic digestion, in addition to the traditional use in cogeneration and trigeneration plants, there is also the possibility to purify biogas by using an up-grading plant and to inject biomethane in the gas network SNAM. This paper analyses technical, economic and environmental feasibility among alternative uses of biogas produced in an anaerobic digestion plant fed by zootechnical wastes eventually integrated with corn silage: • cogeneration plant producing electrical power to satisfy the company needs and to sell to the power grid if exceeding and heat only to warm-up the digester and the post-digester; • cogeneration plant producing electrical power to satisfy the company needs and to sell to the electrical grid if exceeding and heat to warm-up the digester and the post-digester and to feed a dryer for reducing cereals moisture to optimal conditions for their storage; • trigeneration plant producing electrical power to satisfy the company needs and to sell to the electrical grid if exceeding and heat to warm-up the digester and the post-digester and for air-conditioning the company; • regenerative water scrubbing up-grading plant to inject bio-methane into the gas network SNAM. The results of this analysis enable to make a choice not only technologically developed but also economically and environmentally sustainable; it strictly binds to a plant fed by renewable energy sources as the anaerobic digestion is.