Screening-The Preliminary unit operation of Water for the separation of floating matter and harmless solids of diameter more than 3mm, utilising various bars arranged in inclined position with openings of different diameter that obtruct the flow of particles with water.
Sedimentation- The Physical unit operation for the separation of impurities based on their size and density under the influence of gravitational force that encourage the particle to settle down is called sedimentation.
Coagulation- The Chemical unit process for the separation of fine suspended solids and colloids by utilising a trivalent aqua metallic cation as coagulant and colloids that entraps impurities. Coagulation is a three step process which involves rapid mixing,gentle mixing and secondary sedimentation carried out in a three chamber tank.
