Huishan Wastewater Treatment Co., Ltd. approved the use of the TETRA Denite system from Severn Trent Services to remove nitrate-nitrogen (NO3-N) and total suspended solids (TSS) at the wastewater plant, meeting stringent Class IA effluent discharge standards enacted by the China Central Government. Construction of the 25,000 m3/day plant is scheduled for completion in November 2009.The TETRA Denite system from Severn Trent Services removes NO3-N and TSS in a single treatment step. Denite is a fixed-film biological denitrification process that also serves as a deep bed filtration system capable of removing suspended solids to virtually any final effluent requirement. At the Huishan Wastewater Treatment Plant, the Denite system will integrate with other plant treatment processes to provide superior total nitrogen (TN) and phosphorus removal. Denite will be used as the final treatment step in the TN removal process to help the Huishan facility reduce TN influent from 20 mg/l to 15 mg/l and TSS from 40 mg/l to less than 10 mg/l.According to Marwan Nesicolaci, vice president of international sales for Severn Trent Services: “From the standpoint of cost and technical efficiency, biological treatment has become a preferred wastewater treatment choice for many new treatment facilities in China. The TETRA Denite technology has been used successfully throughout the world, including other projects in China.”
