engineering recuitment GATE CE 2023-24 Test Series Environmental Engineering Quality and Characteristics of Sewage
A conventional activated sludge plant designed to treat 40 m3/d of settled sewage having BOD equal to 260 mg/l. The effluent BOD is 20 mg/l, F/M ratio is 0.26, hydraulic retention time is 6 hours, Waste Activated Sludge (WAS) biomass concentration is 6000 mg/l and WAS discharge is 5 m3/d. If the mean cell residence time is X and the recirculation ratio is ‘Y’, the value of 3XY is__________.
Enter numerical value using the virtual keypad. Round off where necessary.