卫生防护距离受限下污水厂的扩建提标工程设计

Design of Wastewater Treatment Plant Expansion and Upgrading Project with Limited Health Protection Distance

随着城市的发展,与周边敏感点的卫生防护距离不足是制约污水厂扩建提标工程实施的主要因素。抚州某污水厂原规模为1.5×10^(4)m^(3)/d,现需扩建至3×10^(4)m^(3)/d,同时出水水质由一级B标准提升至一级A标准,污泥含水率由80%降低至60%,扩建提标工程卫生防护距离受限。实践证明,污水处理工艺采用“改良A^(2)/O+高密度沉淀池+精密过滤器”,污泥处理工艺采用“污泥浓缩池+调理池+厢式隔膜压滤机”,可保证出水水质和污泥含水率稳定达标。通过优化总平布置、采用集约型设计、对构筑物进行加盖除臭等措施,可以降低卫生防护距离,并通过环评报告论证及验收。

The development of the city leads to the lack of health protection distance from the surrounding sensitive points, which has become the main factor restricting the implementation of wastewater treatment plant expansion and upgrading projects. The original scale of a wastewater treatment plant in Fuzhou was 1.5×10^(4)m^(3)/d, and now it needs to be expanded to 3×10^(4)m^(3)/d. In addition, the effluent quality is required to upgrade from first level B standard to first level A standard, and the sludge water content needs to be reduced from 80% to 60%. However, health protection distance of the expansion and upgrading project is limited. The wastewater treatment process of improved A^(2)/O, high density sedimentation tank and precision filter and the sludge treatment process consisting of sludge thickening tank, conditioning tank and van-typed diaphragm filter press ensured that the effluent quality and sludge water content stably met the standard. The health protection distance was reduced by optimizing the general layout, adopting intensive design and covering for deodorization, which had passed the environment impact assessment demonstration and acceptance.