CHARACTERIZATION AND TREATMENT OF WASTEWATER FROM AUTOMOBILE SERVICE STATION

Abstract

Wastewater generated by automobile service stations is one of the sources causing pollution of surface as well as ground water. The water bodies are being polluted increasingly as the growth in automobile population has assumed alarming proportions. The types of waste generated at automobile service stations include; solid material. solvents (paints and paint thinners). antifreeze mixture, brake fluid and brake lining, batteries acid. motor oils. fuels (gasoline. diesel, kerosene). lubricating grease. rubber material- detergents and organic matter. This studv aimed at determininu the sources, quantity and characteristics of wastewater uenerated from automobile service stations and to find out the most economical treatment method. For effective removal of oil contents from wastewater a desiun of proto type 1110del has been carried out. The design of this model is based on the separation of oil and water due to the difference in specific gravities of two liquids. The has been provided coalescor inclined PVC plates and dispersed air floatation systelll tor break inu the oil emulsion and rise of oil contents to the water surface. Fo study the efficiency of the tnodel. the synthetic samples were prepared and run in the oil separator and the oil removal from such sarnples was noted 9()-96 percent. wastewater samples from different autotnobile service stations were analyzed and treated in the nnodel. All other pollutants were in the NEQS limits except oil contents. dissolved and suspended solids. COD and turbiditv. The •treatment of wastewater was carried out in two steps. (l) ()il removal and sedimentation. (2) Allilll treatment. The retuoval of oil contents, solid, COD and turbidity was 5()-92 percent in oil separator and 4 -3 1 percent by alum treatment. The results of the study revealed that the wastewater ii•om automobile service stations is treatable and its recyclinu may control water pollution and conserve our water resources. The recycling of the wastewater is econonlical and due to its execution, the pollutant level will be brought within NEQS linnits and automobile washing cost will be reduced. Finally water recycling process