Enhanced methane bioenergy recovery at Australian piggeries through anaerobic co-digestion: Project 4C-113

Enhanced methane bioenergy recovery at Australian piggeries through anaerobic co-digestion: Project 4C-113

This project was a collaboration between the Pork CRC, Australian Meat Processor Corporation, Queensland Urban Utilities, Melbourne Water Corporation and The University of Queensland. The focus was on anaerobic co-digestion, a method by which the economics of biogas projects are improved by boosting methane production. Co-digestion involves the simultaneous anaerobic digestion of two or more wastes. At a piggery, other wastes (termed co-substrates) might be added together with pig manure (termed base substrate) into a covered pond or digester to boost methane production. Gate fees charged for receiving/treating wastes may provide additional revenue. Of key concern is the microbial health of a digester or covered pond when co-digesting. Poor digestion performance can limit methane production, cause odour, and increase residues to post-handle and dispose of. To prevent unhealthy digesters or covered ponds, safe volumetric and organic loading limits should not be exceeded. Of key concern was a current poor knowledge of the impacts of waste mixture composition and operating temperature on co-digestion loading capacity. To address this, the project was structured into two sub-projects. Sub-project 1 conducted fundamental laboratory studies via two PhD projects (1A and 1B), and Sub-project 2 validated the laboratory results by testing various industrial wastes and monitoring co-digestion trials at full-scale.

Final report prepared for the Cooperative Research Centre for High Integrity Australian Pork.