Publication
Title
Increased salinity improves the thermotolerance of mesophilic nitrification
Author
Abstract
Nitrification is a well-studied and established process to treat ammonia in wastewater. Although thermophilic nitrification could avoid cooling costs for the treatment of warm wastewaters, applications above 40 A degrees C remain a significant challenge. This study tested the effect of salinity on the thermotolerance of mesophilic nitrifying sludge (34 A degrees C). In batch tests, 5 g NaCl L-1 increased the activity of aerobic ammonia-oxidizing bacteria (AerAOB) by 20-21 % at 40 and 45 A degrees C. For nitrite-oxidizing bacteria (NOB), the activity remained unaltered at 40 A degrees C, yet decreased by 83 % at 45 A degrees C. In a subsequent long-term continuous reactor test, temperature was increased from 34 to 40, 42.5, 45, 47.5 and 50 A degrees C. The AerAOB activity showed 65 and 37 % higher immediate resilience in the salt reactor (7.5 g NaCl L-1) for the first two temperature transitions and lost activity from 45 A degrees C onwards. NOB activity, in contrast to the batch tests, was 37 and 21 % more resilient in the salt reactor for the first two transitions, while no difference was observed for the third temperature transition. The control reactor lost NOB activity at 47.5 A degrees C, while the salt reactor only lost activity at 50 A degrees C. Overall, this study demonstrates salt amendment as a tool for a more efficient temperature transition for mesophilic sludge (34 A degrees C) and eventually higher nitrification temperatures.
Language
English
Source (journal)
Applied microbiology and biotechnology. - Berlin, 1984, currens
Publication
Berlin : 2014
ISSN
0175-7598 [print]
1432-0614 [online]
Volume/pages
98:10(2014), p. 4691-4699
ISI
000335460700036
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
[E?say:metaLocaldata.cgzprojectinf]
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 09.02.2015
Last edited 20.11.2017