At a small water treatment plant which has 4 filters the rates of filtration and backwashing are 200 m3/d/m2 and 1000 m3/d/m2

Q. At a small water treatment plant which has 4 filters, the rates of filtration and backwashing are 200 m³/d/m² and 1000 m³/d/m², respectively. Backwashing is done for 15 min per day. The maturation, which occurs initially as the filter is put back into service after cleaning, takes 30 min. It is proposed to recover the water being wasted during backwashing and maturation. The percentage increase in the filtered water produced (up to two decimal places) would be           

Ans: 7.53

Sol: