Sewage Treatment Plant (STP)

Wastewater coming out as effluent from Industries or households enters into raw sewage inlet chambers and then makes its way through a screening chamber where physical separation of organic and inorganic material takes place with the help of a fine and coarse screen. After the raw water moves to the grit removal section where sand, ash as well as clinker is removed and further move towards primary clarifier where sedimentation of solid takes place and excess oil, as well as grease, is removed from the wastewater, helps in reducing the BOD level by almost 15-30 percent. After primary treatment, secondary treatment starts where sewage water or wastewater from the primary tank enters into the aeration tank where sewage water is aerated and microorganism present inside metabolizes the soluble suspended organic matter. The use of aeration tank is to remove the dissolved gases and further oxidize the organic material removing BOD (Biochemical Oxygen Demand) and also reduces the odor of the wastewater. The sewage wastewater from an aeration tank flows towards the secondary settling tank where the separation of biological sludge takes place and in the outlet of the tank, the wastewater is treated with chlorine and final treated water is obtained. The excess sludge from the primary and secondary clarifiers is pumped to sludge thickener to thicken up the sludge which can further be used as a manure in agriculture industries. This is the whole process flow of the Sewage Treatment Plant and one must know it‘s importance in saving water.