Power and limitations of biochemical methane potential (BMP) tests

Abstract

As energy systems transition toward renewable sources, anaerobic digestion (AD), which can be used to recover energy from organic substrates, is receiving growing attention. AD research and practice both rely on biochemical methane potential (BMP) tests to determine the methane potential of sewage sludge, energy crops and organic wastes (Pearse et al., 2018). In contrast to continuous reactor experiments, BMP tests are batch, and can be conducted without a major investment of equipment, labor and time. However, this and other differences limit the applicability of results from a BMP test to full-scale plant operation. Yet even in the peer-reviewed literature, BMP test results are not always used appropriately. An example is the determination of synergistic or antagonistic effects during anaerobic co-digestion in substrate mixtures. A BMP test is a powerful and useful tool, but it is important to recognize the type of questions that can and cannot be answered with this experimental setup. Clarification of these issues is the objective of the present contribution.