Water saving in thermal power plant by use of membrane filter in cooling tower treatment

Abstract

A study was carried to investigate by placing a side stream filter in a cooling tower to observe the water conservation in the system. For any coal based power plant cycles of concentration plays important role for water conservation. The cycles of concentration in cooling tower was increased by installation of membrane system. The drain of the side stream filter was disposed to effluent treatment plant (ETP), while the filtered water will be recycled to the cooling tower inlet. The water parameter was measured by using various flow rates, pressure, and other factors. Significant water savings were demonstrated in the pilot. Maximum make-up water and outflow were both reduced by 14% and 48%, respectively. To save the most water, permeate recovery must be as high as possible. Water savings were minimal due to silica scaling on the membranes. Selected membranes are capable of lower total dissolved system (TDS) rejection than the 88% of total required membranes in the primary study, which might help to save water. The increased energy consumed by membrane treatment was compensated for by lower water outlays. To prevent scaling antiscalent chemical with chemical dosing system was installed along with membrane system.