Flexible feeding in anaerobic digestion - Impact on process stability, performance and microbial community structures.

Flexible feeding in anaerobic digestion - Impact on process stability, performance and microbial community structures. Anaerobe. 2020 Nov 16;:102297 Authors: Weithmann N, Mlinar S, Sonnleitner E, Weig AR, Freitag R Abstract Biogas has the potential to contribute to some of the most urgent issues of the energy transition, including mobility, energy storage, and grid stability. Flexibilization has been discussed as a means to improve the economics of biogas production, ideally restricting the production of electricity to times of strong need. Here the possibility of demand-driven, flexible biogas production is investigated, which saves substrates and storage capacity, while still enabling control over the production of electricity. Effects of different flexible feeding regimes were tested in a continuously operated 200 L reactor. After a period of 300 days under steady conditions (6.4 kg feed m-3d-1), varying flexible feeding patterns were applied over the next 700 days on top of a basic feed load of approximately 1.3 kg m-3d-1. Biogas production, volatile organic acid concentrations, and microbial dynamics were documented. Reduction of feeding resulted in reducing the gas production by up to 80% within a day. By increasing the feed, gas production could rapidly be reinitiated at similar levels as before even after fasting periods of up to 22 days. CH4-contents of the produced biogas were nearly constant over the investigation ...
Source: Anaerobe - Category: Microbiology Authors: Tags: Anaerobe Source Type: research