Solids are settled out of clarifiers by slow mixing a scraper(Figure). The surface loading rate, also called the overflow rate(fluid velocity) is 750 gallons/day/sq.ft. The clarifier surfacearea is 60 ft2. Rotation is 0.5/hr.
a. What work transferred to the wastewater
b. Assuming a motor efficiency of 80%, what is the workperformed by the motor?
c. Calculate the torque required for the scrapers
