On-line nitrification inhibition monitoring using immobilised bacteria

Abstract

As wastewater treatment plant managers are required to meet increasingly stringent standards the focus on processes has shifted more and more towards assessing the treatability of a waste. Many substances discharged to effluent treatment plants may inhibit the process of nitrification. Traditional testing methods are costly and cannot be used for real time control which has led to the development of the AmtoxTM system. AmtoxTM uses a culture of immobilised nitrifying bacteria in a system maintained at 30°C. This enhances the rate of nitrification and gives an early warning of toxicity. This paper presents data comparing Amtox with the conventional nitrification inhibition test method and describes the instrument designed for laboratory use. Preliminary data for the on-line Amtox system are also included: these data provide the first, direct, continuous measure of nitrification inhibition on an effluent treatment plant.