Continuous medium chain carboxylic acids production from excess sludge by granular chain-elongation process

Copyright © 2020 Elsevier B.V. All rights reserved..

Short chain carboxylic acids (SCCAs) production is one of the primary ways to recycle excess sludge (ES). However, the high cost for the SCCAs separation/extraction due to its complete miscibility in water hinders the practical application of SCCAs and the popularization of this recycling way. To overcome this barrier, this study performed an emerging chain elongation (CE) technology to upgrade the SCCAs-rich sludge fermentation broth into the highly hydrophobic medium chain carboxylic acids (MCCAs). In a continuous expanded granule sludge bed (EGSB) reactor, a maximal MCCAs yield of 67.39 % and the corresponding concentration of 9.80 g COD/L (224.97 mM C/L) were achieved. By supplying CO2 at a loading rate of 2 [Formula: see text] to lower the hydrogen partial pressure, the ethanol utilization rate and the resulting MCCAs yield were further improved. In addition, three branched-MCCAs including iso-caproate, iso-heptylate, and iso-caprylate were obtained the first time from waste biomass with the average proportions of 6.17 %, 3.65 %, and 0.8 %, respectively. The branched-MCCAs came from the CE of branched-SCCAs. The granule sludges performing CE were mainly consisted of rod-shaped cells, and dominated by Clostridium sensu stricto and Clostridium IV. This study is expected to lay a foundation for recycling ES to MCCAs.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:402

Enthalten in:

Journal of hazardous materials - 402(2021) vom: 15. Jan., Seite 123471

Sprache:

Englisch

Beteiligte Personen:

Wu, Qinglian [VerfasserIn]
Feng, Xiaochi [VerfasserIn]
Chen, Ying [VerfasserIn]
Liu, Min [VerfasserIn]
Bao, Xian [VerfasserIn]

Links:

Volltext

Themen:

3K9958V90M
Caproate
Carboxylic Acids
Chain elongation
Ethanol
Excess sludge
Granule sludge
Journal Article
Medium chain carboxylic acids
Research Support, Non-U.S. Gov't
Sewage

Anmerkungen:

Date Completed 14.05.2021

Date Revised 14.05.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jhazmat.2020.123471

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM312695616