Mahdieh Asgari Bajgirani - Department of Physical Chemistry, Faculty of Chemistry, University of Lorestan, Lorestan, Iran

Wastewater is the excess water flow caused by water consumption in various human activities that can contain various physical, chemical and biological pollutants and endanger human health by polluting the environment. On the other hand, 99.9% of wastewater is water and only 0.1% of wastewater is external materials including soluble, suspended (sediment able/non-sediment able), organic and inorganic materials. However, the presence of such a seemingly small amount can cause irreparable damage to the environment. Nitrogen and phosphorus compounds in the effluent of wastewater treatment plants cause dangerous problems. Various methods and processes have been used to achieve the reduction of wastewater nitrogen to the standard level at different scales, one of which is the A2/O method in the activated sludge process. It can be shown that 87% of the oxygen required for the nitrification process can be recovered, meaning that this method can be very effective in reducing energy consumption for the use of air blowers.

Activated sludge, Effluent, oxygen, Treatment Plant, Water, Wastewater