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Title: Liquidization of dewatered organic sludge and anaerobic treatment

Abstract

Dewatered sewage sludge was thermochemically liquidized at 175 {degrees}C and the liquidized sludge was separated by centrifugation to 58% (w/w) supernatant and 42% precipitate. The amount of proteins in the liquidized sludge slightly decreased through the liquidization process, however, that of lipids increased. The supernatant separated from the sludge liquidized with dewatered sewage sludge was successfully anaerobically digested. Biogas yield from the supernatant from dewatered sewage sludge at organic loading concentrations of 1.9-2.2 g VS/l during 9 days incubation was 440 ml/g-added VS and digestion ratio was 66% (w/w). Biogas yield in the case of dewatered sewage sludge was 257 ml/g-added VS and digestion ratio was 45%. Similar results were obtained in the case of the anaerobically digested with sewage sludge and dewatered sludge. Anaerobic digestion of the supernatants from the liquidized sludges resulted in high biogas productivity and high digestion ratio compared with these of the original sludges. Moreover, the precipitates contained lower moisture, therefore, they can be incinerated easier than the respective original sludges.

Authors:
; ;  [1]
  1. National Institute for Resources and Environment, Tsukuba, Ibaraki (Japan)
Publication Date:
OSTI Identifier:
430330
Report Number(s):
CONF-960807-
Journal ID: ACFPAI; ISSN 0569-3772; TRN: 97:000003-0009
Resource Type:
Journal Article
Resource Relation:
Journal Name: Preprints of Papers, American Chemical Society, Division of Fuel Chemistry; Journal Volume: 41; Journal Issue: 4; Conference: 212. national meeting of the American Chemical Society (ACS), Orlando, FL (United States), 25-30 Aug 1996; Other Information: PBD: 1996
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 55 BIOLOGY AND MEDICINE, BASIC STUDIES; SEWAGE SLUDGE; BIOCONVERSION; ANAEROBIC DIGESTION; LIPIDS; MOISTURE; PROTEINS; METHANE

Citation Formats

Sawayama, Shigeki, Inoue, Seiichi, and Ogi, Tomoko. Liquidization of dewatered organic sludge and anaerobic treatment. United States: N. p., 1996. Web.
Sawayama, Shigeki, Inoue, Seiichi, & Ogi, Tomoko. Liquidization of dewatered organic sludge and anaerobic treatment. United States.
Sawayama, Shigeki, Inoue, Seiichi, and Ogi, Tomoko. 1996. "Liquidization of dewatered organic sludge and anaerobic treatment". United States. doi:.
@article{osti_430330,
title = {Liquidization of dewatered organic sludge and anaerobic treatment},
author = {Sawayama, Shigeki and Inoue, Seiichi and Ogi, Tomoko},
abstractNote = {Dewatered sewage sludge was thermochemically liquidized at 175 {degrees}C and the liquidized sludge was separated by centrifugation to 58% (w/w) supernatant and 42% precipitate. The amount of proteins in the liquidized sludge slightly decreased through the liquidization process, however, that of lipids increased. The supernatant separated from the sludge liquidized with dewatered sewage sludge was successfully anaerobically digested. Biogas yield from the supernatant from dewatered sewage sludge at organic loading concentrations of 1.9-2.2 g VS/l during 9 days incubation was 440 ml/g-added VS and digestion ratio was 66% (w/w). Biogas yield in the case of dewatered sewage sludge was 257 ml/g-added VS and digestion ratio was 45%. Similar results were obtained in the case of the anaerobically digested with sewage sludge and dewatered sludge. Anaerobic digestion of the supernatants from the liquidized sludges resulted in high biogas productivity and high digestion ratio compared with these of the original sludges. Moreover, the precipitates contained lower moisture, therefore, they can be incinerated easier than the respective original sludges.},
doi = {},
journal = {Preprints of Papers, American Chemical Society, Division of Fuel Chemistry},
number = 4,
volume = 41,
place = {United States},
year = 1996,
month =
}
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