Bioindicators as a tool for monitoring and control biofilm reactors : a simplified approach

Abstract

The control of wastewater treatment plants requires an extensive monitoring programme based on physicochemical costly routine analysis. Microbial populations are well known indicators of operational conditions in biological reactors. This research was carried out by the CENTA and the University of Minho in the scope of the Erasmus programme. The aim of the work was the development of a simplified approach, based on biological indicators, for monitoring small biofilm wastewater treatment processes. In that regard, protozoa and metazoan were monitored at CENTA experimental plants - namely a trickling filter and a rotating biological contactor -, and correlated with influent wastewater and effluent composition. The relationship between wastewater performance and the microbiological composition of the biofilm was identified and assessed. Results indicate that a methodology based on the bioindicators provides useful data for process monitoring and control of small wastewater treatment plants, thus diminishing the associated costs of routine analysis and providing information when such analysis aren’t easily available.