Multi Effect Evaporator Plant (MEE)
Neutral effluent from Primary Treatment Plant is passed through 3 stages Evaporator System and the evaporated water is collected in an Evaporated Water Collection Tank and then recycled to plant after filtering through sand filter and carbon filter. The sludge from the evaporators is filtered through Nutsch Filter whereby solid filtered sludge is obtained and the filtrate is recycled back to process.
Multi stage evaporator (3 – stages) is a long tube forced circulation type evaporators where in the first effect high pressure steam of 7.0 kg/cm2 is used to evaporate waste water. The evaporated water in the form of steam at 2.0 kg/cm2 g pressure is used for evaporating the effluent in the second stage at atmospheric pressure. Evaporated water from the second stage is used for evaporating waste water in the third stage under vacuum of 650- 720 mm Hg. Finally evaporated water from the third stage is condensed in the steam condenser using cooling water on other side. Condensate from all the three stages is collected in condensate receiving tanks, which is pure water and hence reused in the process. Concentrated mass from each effect is collected in the
crystallizer where, on cooling inorganic salts are precipitated along with organic contaminants. This mass is filtered in CF / Nutsch filter and filtrate is recycled back to process.