1. If a flow of 2 MGD were being treated with 20 mg/L of coagulant, how many pounds are used each day?

2. What is the concentration of chemical being fed to a flow of 2.2 MGD if 40 lbs/day of chemical are used?

3. What is the concentration of chemical being fed to a flow of 5 MGD if 28 lbs/day of chemical are used?

4. Convert 8 cuft/day to lbs/min

5. A clarifier is 18 ft long, 8 ft wide and 12 ft deep how many pounds of water will it hold?

Answers:

1. 2 MGD x 20 mg/L x 8.34 lbs/gal = 333.6 lbs

2. 2.2 MGD x 8.34 lbs/gal = 18.348 mlbs/day, next (40 lbs/day) / (18.348 mlbs/day) = 2.2 ppm

3. 5 MGD x 8.34 lbs/gal = 41.7 mlbs/day, next (28 lbs/day) / (41.7 mlbs/day) = 0.67 ppm

4. (8 cuft/day) / (1440 min/day) = .00056 cuft/min x 7.48 gal/cuft = 0.042 gal/min x 8.34 gal/lb= 0.35 lb/min

5. 18’ x 8’ x 12’ = 1728 cuft x 7.48 gal/cuft = 12925.4 gal x 8.34 gal/lb = 107798.2 lbs