Activated Sludge Activity Tests
Activated Sludge Activity Tests
Source:https://www.un-ihe.org/
Authors: Carlos M. Lopez-Vazquez Laurens Welles Tommaso Lotti Elena Ficara Eldon R. Rene Tessa P.H. van den Brand Damir Brdjanovic Mark C.M. van Loosdrecht
Introduction Different conditions and factors affect the degree and rate (speed) at which the compounds and contaminants of concern are removed by microbial populations in biological wastewater treatment systems. Certainly, the plant configuration and operational conditions play a major role in the prevalence of specific microbial populations and their activities, but factors as diverse and broad as wastewater characteristics and environmental and climate conditions have a strong influence as well. Eventually, in any biological wastewater treatment system, there will be a need to assess, define and understand the plant performance with regard to the removal of certain contaminants and the response of the sludge to inhibitory or toxic compounds of interest. Moreover, from a modelling perspective it is also of interest to assess and determine the stoichiometry and kinetic rates of the conversion processes performed by specific microbial populations (e.g. ordinary heterotrophic organisms: OHOs; denitrifying ordinary heterotrophic organisms: dOHOs; ammonium-oxidizing organisms: AOOs; nitrite-oxidizing organisms: NOOs; phosphate-accumulating organisms: PAOs; sulphatereducing bacteria: SRB, also identified as sulphatereducing organisms, SRO (Corominas et al., 2010); or, anaerobic ammonium-oxidizing organisms: anammox. Thereby, the execution of batch activity tests can be rather useful to: (i) study the biodegradability of a given wastewater stream (municipal or industrial), (ii) determine the stoichiometric and kinetic parameters involved in the conversion of a specific compound, (iii) study the potential interactions (e.g. symbiosis and competition) between microbial populations and (iv) assess the potential inhibitory or toxic effects of certain wastewaters, compounds or substances.
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Reproduction
This publication may be reproduced in whole or in part and in any form for educational or nonprofit purposes without special permission from the copyright holders, provided acknowledgement of the source is made. UNEP would appreciate receiving a copy of any publication that uses this publication as a source. No use of this publication may be made for resale or for any other commercial purpose whatsoever without prior permission in writing from the United Nations Environment Programme.
Clearing the Waters A focus on water quality solutions
Reproduction
This publication may be reproduced in whole or in part and in any form for educational or nonprofit purposes without special permission from the copyright holders, provided acknowledgement of the source is made. UNEP would appreciate receiving a copy of any publication that uses this publication as a source. No use of this publication may be made for resale or for any other commercial purpose whatsoever without prior permission in writing from the United Nations Environment Programme.
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