Development of high-performance thermophilic two-phase digestion process

N. Aoki, M. Kawase

Research output: Chapter in Book/Report/Conference proceedingConference contribution

38 Citations (Scopus)

Abstract

Anaerobic digestion of anaerobic sewage sludge leads to the generation of methane gas and reduction of the sludge volume. Because conventional digestion requires a long time, the digestion facilities must be large. We studied decomposing volatile suspended solids (VSS) in sewage sludge, capacitating high acid generation rates and a high-speed methane evolution reactor to reduce retention time for anaerobic digestion. We also studied how to increase VSS reduction ratio by using bio-technology. The high-performance thermophilic two-phase digestion (HPTTD) process is proposed as a innovative digestion system which has high-rate reducing and high-ratio reduction of volatile suspended solids in sewage sludge. This thermophilic digestion process consists of sludge conditioning, acidification and methanation steps. In the sludge conditioning step, sewage sludge is conditioned with thermal treatment and dosed with a protolytic enzyme. In the next step, acidification, acid fermentation is carried out at 70°C; this temperature is higher than that of conventional fermentation (conventional thermophilic digestion process: 55°C). In the methanation step an anaerobic fixed-bed reactor is used. In the digestion experiments using excess sludge, we obtained a 30% higher VSS reduction ratio (78% at HPTTD process) than that of conventional mesophilic digestion.

Original languageEnglish
Title of host publicationWater Science and Technology
Pages1147-1156
Number of pages10
Volume23
Edition7-9
DOIs
Publication statusPublished - 1991
Externally publishedYes
EventProceedings of the 15th Biennial Conference of the International Association on Water Pollution Research and Control - Kyoto, Jpn
Duration: 1990 Jul 291990 Aug 3

Other

OtherProceedings of the 15th Biennial Conference of the International Association on Water Pollution Research and Control
CityKyoto, Jpn
Period90/7/2990/8/3

ASJC Scopus subject areas

  • Environmental Engineering
  • Water Science and Technology

Fingerprint Dive into the research topics of 'Development of high-performance thermophilic two-phase digestion process'. Together they form a unique fingerprint.

  • Cite this

    Aoki, N., & Kawase, M. (1991). Development of high-performance thermophilic two-phase digestion process. In Water Science and Technology (7-9 ed., Vol. 23, pp. 1147-1156) https://doi.org/10.2166/wst.1991.0566