Environmental Engineering The percentage of filtered water, which is used for backwashing in rapid sand filters, is about 2 to 4 0.4 to 1.0 0.2 to 0.4 5 to 7 2 to 4 0.4 to 1.0 0.2 to 0.4 5 to 7 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering The main disadvantage of oxidation pond is that BOD removal is very low None of these Large area is required for construction Maintenance and operation cost are high BOD removal is very low None of these Large area is required for construction Maintenance and operation cost are high ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering In lime-soda process Lime reduces the carbonate hardness and soda-ash removes the non-carbonate hardness Lime reduces the non-carbonate hardness and soda-ash removes the carbonate hardness Only carbonate hardness is removed Only noncarbonated hardness is removed Lime reduces the carbonate hardness and soda-ash removes the non-carbonate hardness Lime reduces the non-carbonate hardness and soda-ash removes the carbonate hardness Only carbonate hardness is removed Only noncarbonated hardness is removed ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering In a BOD test, 1.0 ml of raw sewage was diluted to 100 ml and the dissolved oxygen concentration of diluted sample at the beginning was 6 ppm and it was 4 ppm at the end of 5 day incubation at 20°C. The BOD of raw sewage will be 400 ppm 300 ppm 100 ppm 200 ppm 400 ppm 300 ppm 100 ppm 200 ppm ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering When there is no recirculation of sewage, then recirculation factor is None of these 1 Infinity None of these 1 Infinity ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering The most common cause of acidity in water is Hydrogen Carbon dioxide Nitrogen Oxygen Hydrogen Carbon dioxide Nitrogen Oxygen ANSWER DOWNLOAD EXAMIANS APP