Optimal location and scheduling of booster chlorination stations using EPANET and PSO for drinking water distribution system

Abstract

Chlorine applied at only source provides uneven distribution of residual chlorine at various locations in Drinking Water Distribution System (DWDS), whereas the booster chlorination which reapplies chlorine at strategic locations achieves the uniform chlorine concentration at all locations. The objective of the present work is to optimize the location of booster stations along with minimization of total mass rate of chlorine by developing coupled simulation optimization model using EPANET for hydraulic and water quality simulation and Particle Swarm Optimization (PSO) for optimization. The critical nodes are identified within DWDS by developing impulse response coefficient using EPANET. Manjalpur DWDS network, Vadodara, Gujarat, India is selected for the application of model. Maximum two booster stations are proposed to be selected by the model to find their locations and mass rate of chlorine injection in conjunction with the source chlorination. The optimum solution gives minimum lied dose of chlorine at the same time satisfying the constraint of residual chlorine of 0.2 mg/l (IS 10500 2012 Indian Standard Drinking Water Specification (IS: 10500), Second Revision. (2012). [Google Scholar]) at all the locations within DWDS. Optimization model suggests that reduction of about 30–33% is achieved in booster chlorination along with uniform distribution of chlorine over conventional approach which gives indirect benefit of reducing disinfection by products and overall cost reduction.