Improving Biomethanation of Chicken Manure by Co-Digestion with Ethanol Plant Effluent

Int J Environ Res Public Health. 2019 Dec 10;16(24):5023. doi: 10.3390/ijerph16245023.

Abstract

As the global production of chicken manure has steadily increased, its proper management has become a challenging issue. This study examined process effluent from a bioethanol plant as a co-substrate for efficient anaerobic digestion of chicken manure. An anaerobic continuous reactor was operated in mono- and co-digestion modes by adding increasing amounts of the ethanol plant effluent (0%, 10%, and 20% (v/v) of chicken manure). Methanogenic performance improved significantly in terms of both methane production rate and yield (by up to 66% and 36%, respectively), with an increase in organic loading rate over the experimental phases. Correspondingly, the specific methanogenic activity was significantly higher in the co-digestion sludge than in the mono-digestion sludge. The reactor did not suffer any apparent process imbalance, ammonia inhibition, or nutrient limitation throughout the experiment, with the removal of volatile solids being stably maintained (56.3-58.9%). The amount of ethanol plant effluent appears to directly affect the rate of acidification, and its addition at ≥20% (v/v) to chicken manure needs to be avoided to maintain a stable pH. The overall results suggest that anerobic co-digestion with ethanol plant effluent may provide a practical means for the stable treatment and valorization of chicken manure.

Keywords: anaerobic digestion; chicken manure; co-digestion; co-substrate; ethanol plant effluent.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ammonia
  • Anaerobiosis*
  • Animals
  • Bioreactors*
  • Chickens*
  • Ethanol / chemistry*
  • Manure*
  • Methane / chemistry

Substances

  • Manure
  • Ethanol
  • Ammonia
  • Methane