ENVE 420 Industrial Pollution Control Wastewater Sources in an Industry Dr. Aslıhan Kerç

Classification of Wastewaters Wastewaters from process and operations Cooling waters Cleaning of equipment, production areas, buildings Wastewaters from sub-processes: e.g. Boiler waters (blöf), condensate waters, regeneration water from softening plants Wastewater from toilets, baths, cafeterias (domestic ww characteristics) Storm water (rain water), drainage

Classification of Wastewaters Each source may have different characteristics. Should we mix them and treat together? Or not? If ww generated during cleaning process (cleaning of reactors) contain pollutants, they should be considered as process water.

Process water Flowrates and characteristics vary. Examples: Metal plating industry: plating baths Fertilizer industry: Chemical solution tanks Paint industry: ww generated from cleaning of tanks Cooling water which is in contact with the pollutants Stom water drainage from storage areas should be considered as process ww.

Cooling water Used for cooling of raw material, products or equipment Closed loop  No ww generation (or very small amount) Open loop  Water is used only once or a few times, then discharged H.W. : Cooling water discharge stds

Cooling water If the cooling water is not in direct contact with the equipment, it is not contaminated, generally clean They may contain small amounts of chemicals used for corrosion control  generally negligible. Cause thermal pollution If the cooling water is in contact with the equipment they may contain pollutants and should be considered as process water.

Cooling water In some industries cooling water may contain toxic chemicals. Example? Metal industry

Cleaning water Similar to the cooling water If no contamination  Maybe considered as domestic ww If contaminated  Handle like process ww

Wastewater from sub-processes Sub-process: Not directly related with production Can be classified in process ww according to its characteristics e.g. Boilers: Does not produce highly polluted ww  may not be considered as an important process in terms of water pollution In terms of air pollution  An important process

Storm water drainage If collected seperately and does not have contaminants  clean

Domestic wastewater From toilets, baths, cafeteria There should be a seperate collection system for ww of domestic characteristics. If mixed with process ww  all together considered as process ww.