Assessment of Biogas Production from Source Separated. Fat, Oil and Grease (FOG) from Households

Waste in form of fat, oil and grease (FOG) is generated where food is prepared or consumed, e.g. in households. If collected properly, the household FOG could be interesting for biogas production. This fraction has been source-separated and collected separately in a residential area in Malmö, Sweden. The biogas potential has been evaluated by mesophilic digestion experiments. Both single-substrate digestion of two different FOG fractions and co-digestion of FOG with WWTP sludge or food waste could be achieved in batch laboratory tests. Potential methane production from all FOG (from households and restaurants) in Malmö could in total amount to 1.7-2.8 GWh/year. This makes up about 7-12% of the total methane production from sludge digestion at the largest wastewater treatment plant in the same city.