ETP - AUTOMOBILE BODY PAINT SHOP
The various effluent streams from the paint shop will be segregated into two categories, viz rinse & concentrated effluent. Rinse effluent is basically very dilute effluent streams whereas the concentrated effluents are process bath dumps. The purpose of collecting these effluents separately is to avoid shock loading of the effluent treatment plant.
Accordingly, as explained earlier rinse effluent (continuous flow) as well as rinse bath dumps are collected into the homogenized effluent collection tank. Concentrated effluents from process bath dumps are collected into a dump effluent collection tank. A Small quantity of this dump effluent is gradually transferred to the homogenized effluent collection tank, wherein it will get diluted by other effluents ant will not have any impact on the effluent composition.
The homogenized effluent will be pumped at a flow rate of 4000 lph from the homogenized effluent treatment plant. The downstream effluent treatment plant will operate continuously 24 hrs/day. The effluent treatment process will consists of the following steps:
â— The effluent will be homogenized by air agitation through an air sparger grid provided at the bottom of homogenized collection tank.
â— The homogenized effluent stream will be pumped into a flash mixer tank fitted with a high-speed propeller type agitator.
â— Lime will be dosed for effecting precipitation of heavy metal, and phosphate ions in the effluent. A polyelectrolyte will also be added into the effluent for effecting heavier flocs leading to quicker settling of sludge in the adjacent parallel plate clarifier. The effluent will flow by gravity into the parallel plate clarifier.