3 years ago

Antagonistic effects on biogas and methane output when co-digesting cattle and pig slurries with grass silage in in vitro batch anaerobic digestion

Antagonistic effects on biogas and methane output when co-digesting cattle and pig slurries with grass silage in in vitro batch anaerobic digestion
Anaerobic co-digestion of contrasting substrates can result in synergistic or antagonistic effects on methanogenesis. Biogas and methane yields of the mixtures of cattle slurry (CS1 and CS2) or pig slurry with grass silages (GS1 and GS2) were measured using in vitro anaerobic batch digesters, and synergistic and antagonistic effects were investigated. Slurries and silages were incubated as individual substrates or as part of binary mixtures (slurry:silage mass ratios of volatile solids (VS) of 1:0, 0.75:0.25, 0.5:0.5, 0.75:0.25 and 0:1). The biogas yields of CS1, CS2, pig slurry, GS1 and GS2 were 405.9, 380.4, 550.8, 673.7 and 610.6 L kg−1 of VS, respectively while the corresponding methane yields were 269.1, 246.4, 380.1, 427.7 and 359.0 L kg−1 of VS. The sequential replacement of either cattle slurry by either grass silage caused a progressive increase in biogas and methane yields, but there was not as clear-cut increase when pig slurry was replaced by grass silages. The methane yield for slurry and silage mixtures displayed non-linear blending and the maximum effect, which was always antagonistic, was at a 0.5:0.5 mass ratio of VS, and ranged from 5.7-7.6 % below the yields predicted from mono-digestion of individual substrates.

Publisher URL: www.sciencedirect.com/science

DOI: S0961953417304488

You might also like
Never Miss Important Research

Researcher is an app designed by academics, for academics. Create a personalised feed in two minutes.
Choose from over 15,000 academics journals covering ten research areas then let Researcher deliver you papers tailored to your interests each day.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.