| Article ID: | iaor201530063 |
| Volume: | 47 |
| Start Page Number: | 28 |
| End Page Number: | 33 |
| Publication Date: | Jan 2016 |
| Journal: | Waste Management |
| Authors: | Schmidt Andreas, Koch Konrad, Plabst Markus, Helmreich Brigitte, Drewes Jrg E |
| Keywords: | waste management, chemical engineering, biofuel, biochemistry |
The effects of co‐digestion of food waste in a municipal wastewater treatment plant (WWTP) were studied in batch tests. The results obtained were compared with the mass balance of a digester at a full‐scale WWTP for a one‐year period without and with the addition of co‐substrate. The specific methane yield calculated from the balance was 18% higher than the one in the batch tests, suggesting a stimulation of methane generation by co‐digestion. It was hypothesized that this increase was caused by shifting the C/N ratio of raw sludge (8.8) to a more favourable ratio of the added food waste (17.7). In addition, potential benefits by adding food waste for energy autarky was investigated. While just 25% of the total energy demand of the plant could be recovered by biogas generation when no co‐substrate was fed, this percentage has more than doubled when food waste was added at a ratio of 10% (w/w).