Dairy

Diary is the usually place where milk and all the milk by-products are stored and processed. After processing (chilling, pasteurization, homogenization) raw milk is transformed in butter, cheese, ice cream yogurt and all kind of milks.

The diary industry generates wastes, odours and dusts. The wastewater contains sugars, proteins, fats, residues of additives and so on. These pollutants involve especially a high BOD (mainly from cream, butter and cheese processing), COD and some issues with the TSS (total suspended solids) and TDS (total dissolved solids) rate as you can see in the table bellow.

BOD	0.8 to 2.5 kg/ton of milk
COD	around 1.5*BOD
TSS	100-1000 mg/l
TDS	phosphorus 10-100 mg/l around nitrogen 5% of BOD level

Treatment of the wastewater:

pretreatment neutralization, screening, flow equalization, air flotation
ozone disinfection.
Biological treatment: trickling filters, rotating biological contactors, activated sludge