Enhancing methane production from waste activated sludge using combined free nitrous acid and heat pre-treatment

Wang, Qilin, Jiang, Guangming, Ye, Liu and Yuan, Zhiguo (2014) Enhancing methane production from waste activated sludge using combined free nitrous acid and heat pre-treatment. Water Research, 63 71-80. doi:10.1016/j.watres.2014.06.010

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
UQ334608OA.pdf Full text (open access) application/pdf 1.75MB 0

Author Wang, Qilin
Jiang, Guangming
Ye, Liu
Yuan, Zhiguo
Title Enhancing methane production from waste activated sludge using combined free nitrous acid and heat pre-treatment
Journal name Water Research   Check publisher's open access policy
ISSN 0043-1354
Publication date 2014-10-15
Year available 2014
Sub-type Article (original research)
DOI 10.1016/j.watres.2014.06.010
Open Access Status Not Open Access
Volume 63
Start page 71
End page 80
Total pages 10
Place of publication Oxford, United Kingdom
Publisher Elsevier Ltd
Language eng
Subject 2312 Water Science and Technology
2311 Waste Management and Disposal
2310 Pollution
2302 Ecological Modelling
Abstract Methane production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow degradation and poor substrate availability of WAS. Our previous study revealed that WAS pre-treatment using free nitrous acid (FNA, i.e. HNO2) is an economically feasible and environmentally friendly method for promoting methane production. In order to further improve methane production from WAS, this study presents a novel strategy based on combined FNA and heat pre-treatment. WAS from a full-scale plant was treated for 24h with FNA alone (0.52-1.43mgN/L at 25°C), heat alone (35, 55 and 70°C), and FNA (0.52-1.11mgN/L) combined with heat (35, 55 and 70°C). The pre-treated WAS was then used for biochemical methane potential tests. Compared to the control (no FNA or heat pre-treatment of WAS), biochemical methane potential of the pre-treated WAS was increased by 12-16%, 0-6%, 17-26%, respectively; hydrolysis rate was improved by 15-25%, 10-25%, 20-25%, respectively, for the three types of pre-treatment. Heat pre-treatment at 55 and 70°C, independent of the presence or absence of FNA, achieved approximately 4.5 log inactivation of pathogens (in comparison to ~1 log inactivation with FNA treatment alone), thus capable of producing Class A biosolids. The combined FNA and heat pre-treatment is an economically and environmentally attractive technology for the pre-treatment of WAS prior to anaerobic digestion, particularly considering that both FNA and heat can be produced as by-products of anaerobic sludge digestion.
Keyword Anaerobic digestion
Free nitrous acid
Waste activated sludge
Q-Index Code C1
Q-Index Status Confirmed Code
Grant ID DP120102832
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: School of Chemical Engineering Publications
Official 2015 Collection
Advanced Water Management Centre Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 39 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 39 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 15 Jul 2014, 10:12:23 EST by System User on behalf of Advanced Water Management Centre