The types of sewage treatment facilities are:
Basic treatment-including screening and sand removal, to separate hourglass with a diameter of more than 2.5 mm and suspended solids with a diameter of more than 6 mm from sewage.
Primary treatment-including screening, sand removal and primary precipitation treatment. After the basic treatment, the sewage will continue to precipitate for a long time to separate out fine suspended solids.
Chemical enhanced primary treatment-adding appropriate amount of ferric chloride and polymer to sewage to enhance the ability to reduce suspended solids and biochemical oxygen demand in sewage. After chemical action, the suspended solids in sewage will condense into larger solids and deposit at the bottom of the pond. These precipitated sludge will be separated by machines.
Secondary treatment-after the sewage passes through the screen (primary treatment), it will not only precipitate to remove fine suspended solids, but also flow into the aeration tank, so that microorganisms in the tank can decompose the organic matter in the sewage and then disinfect it.
Finally, the treated sewage will be discharged into the sea, rivers and inland waters through the discharge port.