Biogas Micro-Production from Human Organic Waste - A Research Proposal

Organic waste (OW) management tackles the problem of sanitation and hygiene in developing countries and humanitarian camps where unmanaged waste often causes severe health problems and premature death. OW still has a usable energy content, allowing biogas production, potentially contributing to satisfy the local needs, e.g., cooking, lighting and heating. Digesters are the devices converting OW into biogas under anaerobic conditions. They are simple and effective solutions for the OW management in rural areas, humanitarian camps and remote developing regions, producing energy and fertilizers for local farming as residual. This paper describes the design and lab-test of a domestic OW management system integrating a waterless toilet with a small-scale digester producing safe biogas for local micro-consumption. Starting from people’s needs and an extensive review of the current state-of-art technology, the proposed system’s key innovation and strength is the combination of effectiveness and a very simple construction, set up and use, fitting with the rural conditions and raw materials available within the emerging countries. A small-scale prototype is assembled and lab-tested assessing the quantity—i.e., productivity—and quality—i.e., composition and methane content—of the produced biogas. The measured productivity in terms of specific biogas production (SBP) is of about 0.15 m3/kgSV and a methane content of about 74% in mass match the energy needs of domestic users, encouraging the spread of such systems in developing regions and rural areas.