Physical treatment facilities are a method of removing relatively large suspended solids in the first treatment stage of water purification plants and wastewater treatment, and are classified into screens, sedimentation ponds, sedimentation ponds, and adsorption. Chemical treatment has various purposes depending on the nature of the wastewater and the type of process, including fine suspended substances. And COD removal, PH control, oxidation treatment of CN, reduction treatment of CR+6, removal of NP, etc., as well as physical treatment, the system is achieved through complex combination rather than individual treatment.

Physical/Chemical/Tunnel wastewater treatment facilities administer chemicals to inorganic colloidal solids and heavy metals and contaminants existing in a dissolved state in wastewater to undergo physical and chemical reactions such as oxidation, reduction, and condensation into wastewater. Methods for removing contained contaminants are broadly divided into coagulation sedimentation and cohesion flotation treatment, and complex treatment methods mainly used.