Semi-Dry / Dry Anaerobic Digestive Systems

Semi-dry and dry anaerobic digestion treats the organic fraction of waste that carries little free liquid — solids from the sewage treatment process, and organic kitchen waste generated in homes and communities — in a sealed, oxygen-free digester that recovers biogas from material otherwise sent to landfill.

Ion Exchange offers two systems for this duty, both built on INDION IPC MBR and the INDION Advanced Bio-methanation process. ANDICOS® Waste To Energy integrates those technologies to treat a combination of the solid waste generated in the sewage treatment process and organic kitchen waste from homes and communities. The INDION Integrated Waste Management System applies the same pairing to liquid waste — sewage and sullage — alongside that organic kitchen waste.

How It Works

Prepared organic waste is fed into a sealed digester from which oxygen is excluded. Without it, the bacterial community breaks the biodegradable fraction down through hydrolysis, acidogenesis and methanogenesis rather than oxidising it, and the methane-rich biogas that results is drawn off the digester as the process’s energy output.

Semi-dry and dry digestion run at a higher solids content than conventional wet digestion. That is what suits them to feedstocks with little free liquid — screened kitchen waste and sewage solids — which can be digested as they are rather than diluted back to a pumpable slurry first.

Systems in This Range