A primary sedimentation tank that has a removal efficiency of 65% and settles out solids from a wastewater that has concentration of 220 mg/L. The wastewater flows into the sedimentation tank at a rate of 2.35 million gallons per day (MGD). How many tons (as dry mass) of primary sludge are produced each day?

Question

A primary sedimentation tank that has a removal efficiency of 65% and settles out solids from a wastewater that has  concentration of 220 mg/L. The wastewater flows into the sedimentation tank at a rate of 2.35 million gallons per day (MGD). How many tons (as dry mass) of primary sludge are produced each day?

The answer is 1.40 tons, but I don't know how to do it.

bobpursley · Answer

tons=.65*.220g/liter*3.9liters/gal*2.35e6gallons/day*ton/9.06e5 grams=140 tons those tons are US tons, not metric.