A TREAMENT OF DOMESTIC SEWAGE AND GENERATION OF BIO SLUDGE USING NATURAL COAGULANTS

Abstract

The waste generated from various human activities promotes an environmental degradation. Sewage a waste produced through human is a source of water pollution. An improper handling of sewage and waste generated from societies pollutes fresh water bodies. In Indian conditions, conventional treatments like Activated Sludge Process, Oxidation Ponds, Aerated lagoons, and Trickling filters are the most suitable treatment process to treat sewage generated in urban areas. While the land required to setting conventional treatment plant along with energy and time required is more which increases overall cost of the treatment process. To upgrade conventional treatment process and reduce cost of treatment, uses of natural coagulants are best alternative. The study is carried out to check efficiency of combinations of natural coagulants in different preparations, to treat sewage. Natural coagulants extracted from seeds of Acacia Nilotica [Babul] and Mangifera Indica [Mango] are used with different combinations to treat sewage. After laboratory analysis of treated water through primary treatment process shows around 45% and 56 % of BOD and TSS removal respectively which is more than primary settling tank of conventional treatment process. Which will increases efficiency of primary treatment and reduces organic loading over secondary treatment. Due this the size of secondary unit can be reduced so area of land required to set plant can also be reduced. Use of natural coagulants will minimize time and energy required for aeration. Also sludge generated through primary treatment process will effectively used as soil stabilizer after proper composting. This study aims to reduce overall cost of sewage treatment along with recovery of plant nutrients as compost.