Continuous H2 and CH4 production from high-solid food waste in the two-stage thermophilic fermentation process with the recirculation of digester sludge

Dong Yeol Lee, Yoshitaka Ebie, Kai Qin Xu, Yu You Li, Yuhei Inamori

Research output: Contribution to journalArticlepeer-review

177 Citations (Scopus)

Abstract

A thermophilic two-stage fermentation process using 10% total solids (TS) food waste was tested at varying organic loading rates (OLRs). The system was configured to produce H2 and CH4 in conjugation with the chemical oxygen demand (COD), nitrogen removal, and adjustment of the pH by returning sludge as an alkali buffer from the sludge storage tank for denitrification. The pH in the H2 fermentation reactor was maintained in the range of 5.4-5.7 using sludge recirculation (Qr/Qi ratio 1). The average H2 (11.1 l-H2 l-1-fed d-1) and CH4 (47.4 l-CH4 l-1-fed d-1) production rates were achieved at OLRs of 39 (H2 fermentation reactor) and 4.16 gCOD l-1 d-1 (CH4 fermentation reactor), respectively. These results suggest that long-term stability of the continuous two-stage process can be successfully achieved by recirculation of high-alkalinity sludge of 6.7-7.5 g l-1 as CaCO3, without any added external chemical buffer.

Original languageEnglish
Pages (from-to)S42-S47
JournalBioresource Technology
Volume101
Issue number1 SUPPL.
DOIs
Publication statusPublished - 2010 Jan

Keywords

  • Hydrogen
  • Methane
  • Organic loading rate
  • Thermophilic fermentation
  • Two-stage process

ASJC Scopus subject areas

  • Bioengineering
  • Environmental Engineering
  • Renewable Energy, Sustainability and the Environment
  • Waste Management and Disposal

Fingerprint

Dive into the research topics of 'Continuous H<sub>2</sub> and CH<sub>4</sub> production from high-solid food waste in the two-stage thermophilic fermentation process with the recirculation of digester sludge'. Together they form a unique fingerprint.

Cite this