Sewage Treatment Plant Lab Questions with Answers

Combined treatment system Correct Answer carrys away both water polluted by humans use and water polluted as it drains off homes, streets, or land during a storm What is D.O. and why is it important? Correct Answer Dissolved Oxygen maintains life in aquatic areas. If to low life in water will die What is B.O.D. and why is it important? Correct Answer biochemical oxygen demand is important because if it is to high then it will decrease the amount of O2 in the water which then can not support aquatic life. primary treatment of sewage Correct Answer a mechanical process in which large solids are removed by screening and some suspended solids are removed by settlement (sedimentation) secondary treatment of sewage Correct Answer a biological oxidation process in which the levels of suspended and dissolved organic materials are reduced, i.e. the sewage is decomposed by means of bacteria which use the nutrients from the sewage together with oxygen from the air to break down the sewage