Dairy Industry Wastewater Treatment

These effluents have the following characteristics

  • Biochemical oxygen demand (BOD), with an average ranging from 0.8 to 2.5 kilograms per metric ton (kg/t) of milk in the untreated effluent
  • Chemical oxygen demand (COD), which is normally about 1.5 times the BOD level
  • Total suspended solids (TSS), at 100–1,000 milligrams per liter (mg/l)
  • Total dissolved solids (TDS): phosphorus (10–100 mg/l), and nitrogen (about 6% of the BOD level).

Cream, butter, cheese, and whey production are major sources of BOD in wastewater. The waste load equivalents of specific milk constituents are:

  • 1 kg of milk fat = 3 kg COD
  • 1 kg of lactose = 1.13 kg COD
  • 1 kg protein = 1.36 kg COD
The reuse of wastewater from the dairy industry can also be provided for by usage of adsorption and membrane separation among other processes. The color and the odor may be removed completely after activated carbon treatment. The pretreated water can be passed through a cross flow reverse osmosis membrane system and the permeate water can then be reused.
Filtration Media