Study And Design Of Baodi District's Wastewater Treatment Project

Baodi District, a small town, is located in the northern part of Tianjin. There is an existing plant of sewage treatment for daily discharge in the south of Baodi, but it is not enough to fulfill the requirements of the development for the rate and depth of treatment. The more comprehensive and extensive modern sewage treatment plant is in urgent need.Municipal wastewater takes larger proportion by analysis of water quality of sewage discharge in Baodi. Effluent water for sewage discharge is required by"discharge standard of pollutants for municipal wastewater treatment plant"GB18918-2002 of class A, so biological nitrogen and phosphorus removal is provided for the high removal of pollutants.This article presents further and detailed analysis for Biological Nitrogen and Phosphorus Removal, comparative descriptions for A/A/O, Oxidation Ditch and SBR etc. According to treatment scale, influent quality and effluent requirement, two spares of Step-feeding A/A/O and Carrousel 2000 Oxidation Ditch are available for sewage treatment, and by further compare on costs of investment and business, the former is preferred.It is difficult to reach class A for secondary sedimentation tank effluent only by biology technique, so post-processing chemical phosphorus removal is added to secure the water quality.Biological sludge is produced in proceeding of biology treatment, if not treat properly, it will bring secondary pollution. Mechanical concentration dewatering is used for sludge dewatering by technical and economic proof. Sludge is to be disposed by way of being taken outward after treatment.Furthermore, this article also presents detailed planning for general design and process design.The recent design scale is 30,000 m~3 / d for the project, long-term design scale 50,000 m~3 / d, budget for total investment 75.6857 million yuan and plot area 70.23 acres.