Methods for determination of biomethane potential of feedstocks: a review

Document Type: Review Paper

Authors

Chinhoyi University of Technology, P. Bag 7724, Chinhoyi, Zimbabwe.

Abstract

Biogas produced during anaerobic digestion (AD) of biodegradable organic materials. AD is a series of biochemical reactions in which microorganisms degrade organic matter under anaerobic conditions. There are many biomass resources that can be degraded by AD to produce biogas. Biogas consists of methane, carbon dioxide, and trace amounts of other gases. The gamut of feedstocks used in AD includes animal manure, municipal solid waste, sewage sludge, and various crops. Several factors affect the potential of feedstocks for biomethane production. The factors include nutrient content, total and volatile solids (VS) content, chemical and biological oxygen demand, carbon/nitrogen ratio, and presence of inhibitory substances. The biochemical methane potential (BMP), often defined as the maximum volume of methane produced per g of VS substrate provides an indication of the biodegradability of a substrate and its potential to produce methane via AD. The BMP test is a method of establishing a baseline for performance of AD. BMP data are useful for designing AD parameters in order to optimise methane production. Several methods which include experimental and theoretical methods can be used to determine BMP. The objective of this paper is to review several methods with a special focus on their advantages and disadvantages. The review shows that experimental methods, mainly the BMP test are widely used. The BMP test is credited for its reliability and validity. There are variants of BMP assays as well. Theoretical models are alternative methods to estimate BMP. They are credited for being fast and easy to use. Spectroscopy has emerged as a new experimental tool to determine BMP. Each method has its own advantages and disadvantages with reference to efficacy, time, and ease of use. Choosing a method to use depends on various exigencies. More work needs to be continuously done in order to improve the various methods used to determine BMP.

Graphical Abstract

Methods for determination of biomethane potential of feedstocks: a review

Highlights

  • The biomethane potential (BMP) provides baseline data for the performance of AD.
  • Both experimental and theoretical methods to determine BMP have been reviewed.
  • The BMP test is the most widely used method and is credited for reliability and validity of its results.

Keywords


[28] Elbeshbishy, E., Nakhla, G., Hafez, H., 2012. Biochemical methane potential (BMP) of food waste and primary sludge: influence of inoculum pre-incubation and inoculum source. Bioresour. Technol. 110, 18-25.

[32] European Communities (EC), 2002. Proceedings of the workshop on hamornisation anaerobic biodegradation, Activity and Inhibition Assays, Lago d’Orta, Italy.

[37] Gerardi, M.H., 2003. The microbiology of anaerobic digesters, John Wiley & Sons.

[46] International Energy Agency, 2009. Biogas production and utilization, IEA Task 37 Brochure. International Energy Agency, Paris.

[47] International Energy Agency, 2013. Biogas production and utilization.

[66] McCarty, P.L., 1972. Energetics of organic matter degradation, in: Mitchell, R. (Ed.), Water Pollution Microbiology. John Wiley & Sons, Inc., New Jersey, pp. 91-118.

[101] VDI 4630, 2006. Fermentation of organic materials-characterisation of the substrate, sampling, collection of material data, fermentation tests, VDI Guideline 4630. Verein Deutscher Ingenieure, Düsseldorf.