Formulas

Alkalinity = mls of titrant  x  acid normality  x  50,000mls of sample

Area

  • Circle = 0.785 x Diameter2 OR x Radius2
  • Rectangle = Length x Width
  • Triangle = Base  x  Height2

Chemical dosage, lbs/day = mg/L x MGD x 8.34

Chemical feed, lbs/day = dose  x  MGD  x  8.34% purity (decimal)

Circumference = (π) (Diameter) OR (2) (π) (Radius)

Detention Time = volumeflow

Dilution = C1V1 = C2V2

Efficiency, % = In-OutIn x 100

Food/Microorganism Ratio = BOD, lbs/dayMLVSS, lbs

Horsepower

  • WHP = Flow, gpm  x  Head, ft3960
  • BHP = WHP% Efficiency (decimal)

MCRT = MLSS, lbs(solids in the effluent, lbs/day) + (solids wasted, lbs/day)

Sludge age = SS in aeration, lbsSS added, lbs/day

Slope = Drop or RiseDistance

Sludge Volume Index (SVI) = Settleable Solids, mL/L x 1,000MLSS,  mg/L

Solids, mg/L = Dry Solids, grams x 1,000 mg/G x 1,000 ml/Lmls of sample

Velocity, ft/sec = Distance,  ftTime,  min

Volatile Solids, % = Dry Solids, grams – Ash, grams x 100Dry Solids, grams

Volume

  • Cone = 1/3 x r2 x height
  • Cylinder = r2 x height
  • Rectangle = L x W x H