Key Features of Municipal Sewage Treatment Plant

• The raw sewage is pumped to the inlet chamber of treatment plant, from there it flows to screen chamber where physical separation of floating and suspended organic and inorganic materials takes place.
• The sewage water from screen chamber flows to grit chamber, where coarse particles of sand, ash and clinkers, egg shells, bone clips and inert materials are removed.
• The sewage water from grit chamber flows to primary clarifier where sedimentation of settle able solids takes place. Primary clarifier also reduces the organics load on secondary treatment units.
• The sewage water from primary clarifier flows to aeration tank, where the sewage containing waste organic matter is aerated and micro-organisms metabolise the soluble and suspended organic matter.
• The waste water from aeration tank flows to secondary settling tank, where separation of biological sludge takes place. The efficient separation of the biological sludge is necessary for ensuring final effluent quality and also for return of adequate sludge to maintain the MLSS level in the aeration tank.
• The treated water from secondary clarifier collected in treated water collection tank is pumped for final disposal.
• The excess sludge from secondary clarifier and sludge from primary clarifier is pumped to sludge thickener for thickening of sludge.
• The thickened sludge from sludge thickener is pumped to sludge digester for anaerobic sludge digestion.
• The digester sludge is taken to centrifuge or sludge drying bed for sludge dewatering.
• The filtrate from dewatered sludge is collected in a sump and pumped back in inlet chamber.