Filtration

1.  If a sand filter is 18 feet wide and 24 feet long and receives a flow of 750 gpm,
     what is the filter loading rate in gpm/ft²?

a.  .576 gpm/ft² b.  1.7 gpm/ft² c.  3.52 gpm/ft² d.  4.1 gal/min

2.  A gravity flow filter bed measures 10 feet wide, 20 feet long, and 4 feet deep.
     If 375,000 gallons are filtered in a 12-hour period, what is the filter loading rate
     in gpm/ft²?

a.  1.3 gph/ft² b.  1.3 gal/ft² c.  2.6 gpm/ft² d.  3.0 gal/hour

3.  How many gallons can be treated in one day by a filter measuring 20 feet long,
     10 feet wide, and 6 feet deep if the filtration rate is 3 gpm/ft²? 

a.  384,112 gal b.  550,612 gal c.  864,000 gal d.  1.2 mg/ft³

Ion-Exchange

          4.  An ion-exchange unit is removing 450 ppm of hardness from the well water.
               How many grains per gallon (g/g) are being removed? 

a.  13.3 g/g b.  18.1 g/g c.  22.6 g/g d.  26.3 g/g

5.  Water from the system measures 5 g/g hardness.  How many ppm is this?

a.  85.5 ppm b.  124.2 ppm c.  240.1 ppm d.  86 grains

         6.  The total hardness of your water is 280 ppm.  The softener can remove 140,000
              grains before it needs to regenerate.  How many gallons will it treat before 
              regeneration?

a.  500 gallons b.  4,788 gallons c.  8,552 gallons d.  10,222 gallons

7.  A treatment unit contains 20 ft³ of cation exchange material that has a rated 
     removal capacity of 20,000 grains per cubic foot.  What is the total hardness
     removal capacity in grains?         

a.  100,000 grains b.  250,000 grains c.  400,000 grains d.  1,000,000 grains

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