Watrion water & filter engineering has developed treatment scheme for effluent water for industries. The scheme not only treats water to meet pollution control board standard, but also enables about 70% of it recycled. The scheme includes collection of effluent of various batches in a balancing tank, injecting air into the tank to mix the effluent and to reduce the bod and cod. Lime solution is added into this tank to increase the ph for proper reaction with coagulants injected upstream. The water is pumped into a flocculent chamber where coagulant is added for creation of dense flocs for better settling. The treated effluent is allowed to settle in a clarifier where the sludge is settled at the bottom and clear water flows from the overflow launders. The sludge collected at the sloping bottom is collected in a sludge drying bed by gravity or by means of sludge re-circulation pumps. The clear water is filtered in a sand filter and activated carbon filter to remove remaining suspended matter, colour, odour, organic matter, part of cod and bod. The water becomes fit for process use.
