According to the above contract, technical services and studies related to the study of the South Isfahan Wastewater Treatment Plant Upgrade and Development Project have been assigned to this consultant.

The purpose of the study is to increase the capacity and quality of the wastewater output of the South Isfahan Wastewater Treatment Plant by making maximum use of the current and existing facilities and equipment of the treatment plant and based on the latest design criteria, environmental standards, and world-class technology.

In the South Isfahan Wastewater Treatment Plant Upgrade and Development Project, raw wastewater first enters the grit unit to remove minerals with a diameter larger than 1 mm and then is transferred to the pumping station unit. In order to provide the necessary head for the process units, after the wastewater is lifted about 5 meters by screw pumps, the wastewater is directed to the coarse and then fine debris removal unit.

After separating the suspended matter to remove particles with an average diameter of 0.2 to 0.1 mm, the wastewater enters the grit unit.

After removing the granular materials, the raw wastewater enters the primary sedimentation unit to reduce the BOD and TSS concentration of the input and then enters the biological treatment system to complete the treatment process, which includes anaerobic, anoxic, aerobic and secondary sedimentation units. In this method, in addition to removing BOD and COD, phosphorus, nitrification and denitrification also occur. Finally, the effluent from the secondary sedimentation unit enters the filtration unit and, after passing through the disinfection unit, is directed to the outlet channel.