Wastewater treatment of bottle oil washing water (BOWW) by hybrid coagulation–flocculation and biological process

Abstract

AbstractThe efficiency of physico-chemical and biological combined treatment processes of bottle oil washing wastewater (BOWW) was investigated. The coagulation and flocculation process followed by activated sludge treatment was carried out in order to produce a suitable chemical oxygen demand (COD) and oily effluent in conformity with the regulatory standards. Attempts were made in this study to examine the effectiveness of the coagulation and flocculation process using aluminium sulfate and polyelectrolyte (non-ionic preastol) for the treatment of BOWW. The removal of organic matter (COD), oil and color using Al2(SO4)3·18H2O and preastol during coagulation–flocculation process was investigated. Also, the optimum conditions for the coagulation–flocculation process, such as coagulant dosage, polyelectrolyte dosage, and solution pH were investigated using jar-test experiment. Results revealed that in the tested pH range tested, the optimal operating pH was 6.5. Removal percentage of 87, 95, and 97% for COD...