Application of partial least-squares modelling in the optimization of a waste-water treatment plant

Abstract The partial least-squares method was applied to data collected at a municipal waste-water treatment plant to estimate the relationship between the process parameters and effluent quality. The main reason for poor treatment efficiency was the so-called bulking phenomemon of the activated sludge. The PLS model of the data presenting a normal period of operation and the bulking period thereafter showed that high temperature and decreasing concentrations of carbon and phosphorus contributed to the bulking state.