Control of Electrocoagulation Batch Reactor for Oil removal from Automobile Garage Wastewater

Wastewater from Automobile garages and workshops is an important contributor to the water pollution. Oil is one of the major content of wastewater from vehicle garages. The work focuses on the design of an electrocoagulation (EC) reactor for the removal of oil content in wastewater from Automobile garages with automation and control for efficient operation. The samples for the study were collected from Kerala State Road Transportation(KSRTC) Thrissur depot. Experimental study has been conducted to investigate the influence of various factors affecting electrooagulation. Major factors selected were current density, time of EC, salt concentration and pH on oil removal. The influence of these factors on percentage oil removal was found to be non-linear. Experiments were designed by Response Surface Method(RSM) and a nonlinear empirical relationship between percentage oil removal and input parameters was obtained. Responses were optimized using MINITAB software and these values were used in the control purpose. Control and automation of electrocoagulation process was developed with reaction time in the batch electrocoagulation reactor as the controlling variable. Power supply to the electrodes was also controlled with a level switch. Both inlet and outlet control were proposed for the efficient run of the batch EC reactor.