Anaerobic digestion of food waste for volatile fatty acids (VFAs) production with different types of inoculum: effect of pH

Bioresour Technol. 2014 Jun:161:395-401. doi: 10.1016/j.biortech.2014.03.088. Epub 2014 Mar 27.

Abstract

Food waste anaerobic fermentation was carried out under acidic conditions using inocula based on aerobic activated sludge (Inoculum AE) or anaerobic activated sludge (Inoculum AN) for volatile fatty acids (VFAs) production. The results showed that food waste hydrolysis increased obviously when Inoculum AN was used relative to Inoculum AE at any pH investigated. Hydrolysis at pH 4.0 and uncontrolled pH was higher than that at other pHs when either inoculum was used. Additionally, VFAs production at pH 6.0 was the highest, regardless of the inoculum used. The optimum VFA yields were 0.482g/gVSSremoval with Inoculum AE and 0.918g/gVSSremoval with Inoculum AN, which were observed after 4d and 20d of fermentation, respectively. VFAs composition analysis showed that butyrate acid was the prevalent acid at pH 6.0, followed by acetate acid and propionic acid.

Keywords: Anaerobic fermentation; Food waste; Inoculum; Volatile fatty acid; pH.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Fatty Acids, Volatile*
  • Fermentation*
  • Garbage*
  • Hydrogen-Ion Concentration
  • Hydrolysis

Substances

  • Fatty Acids, Volatile