Brief Introduction to the Third Waste Water Treatment Plant in Chenzhou
Located at the west bank of East River, Jintian Village, Bailutang Town, Suxian District of Chenzhou City, the Third Sewage Treatment Plant of Chenzhou City serves the Banqiao-Bailutang Cluster of the new urban district under planning, that is, the new urban district on the east of the West River, covering a population of 230,000 in the long term,daily capacity 180,000 cubic meters.Adopted in the plant is the A2/O process, namely, the anaerobic- hypoxic-aerobic treatment process as illustrated below:
The pretreatment structures like the coarse screens, booster pump chamber, fine screens and sedimentation tank remove the big-size floaters, part of the suspended matters and grains in the sewage water first; the feed water then enters the biological treatment section- the A2/O bio-tank, wher_e COD, NH3-N and total P are removed; the outlet water then enters the secondary sedimentation tank for sludge and water separation and clearing, after which the water goes to the ultraviolet disinfection tank and finally discharged to the East River nearby. Most of the sludge at the bottom of the secondary sedimentation tank is returned to the A2/O bio-tank, while a small portion is pumped to the sludge storage tank, and removed and buried in fillings afterwards after dewatering via the belt filtering press.
The designed indexes of quality of water entering the plant are COD 280mg/l, BOD5 130 mg/l, SS 220 mg/l, TN 30 mg/L, NH3-N 20 mg/l and TP 3 mg/l；while the outlet water quality shall meet Grade-1 B standards of Discharge Criteria of Pollutants for Municipal Waste-water Treatment Plants, specifically: COD ≤60mg/l, BOD5≤20 mg/l, SS ≤20 mg/l, TN ≤20 mg/l, NH3-N ≤8 mg/l and TP ≤1.0 mg/l. Annually, the plant could reduce the discharge of COD by 15,000 tons；BOD by 1,807 tons；SS by 3,285 tons；TN by 164 tons and TP by 33 tons.
Hydrochina Zhongnan Engineering Corporation undertook this project on EPC basis,The Project was started in November, 2009.The Project was checked and accepted by the employer on December 18th, 2010. It was taken over by Guiyang City Construction Investment Company Limited on December 21st, 2012. The warranty period stated in the contract was from December 21st, 2010 to December 20th, 2012.