Characterization of textile wastewater and other industrial wastewaters byrespirometric and titration biosensors

Many industrial effluents, such as textile and tannery wastewater, contain slowly biodegradable, refractory or even toxic compounds at variable concen trations which may interfere with the efficient operation of biological was tewater treatment plants, in particular with the nitrification stage. Agro- industrial effluents may occasionally contain sanitising agents which are b y definition biocides. Two different biosensors, based on respirometry (oxy gen uptake rate, OUR measurements) and on basic titration respectively, wer e used to measure degradation rates of industrial wastewater samples by aut otrophic bacteria (ammonia oxidizers). Specific sanitisers such as sodium h ypochlorite and benzalconium chloride were used to evaluate and compare the nitrifying activity measured by the two different instruments. (C) 1999 IA WQ Published by Elsevier Science Ltd. All rights reserved.