摘要
Abstract
With the acceleration of urbanization,non-point source pollution of urban surface runoff is an important factor affecting the quality of river water environment.Adding initial rainwater storage tanks at the current drainage pumping station at the end of the drainage system is one of the important engineering measures to control runoff pollution in built urban areas.The paper takes the design of initial rainwater storage tank in an existing system in Shanghai as an example,and introduces the construction type,equipment selection,process parameters,and operation mode of the initial rainwater storage tank based on the land conditions and surrounding environment.The design scale of the storage tank is 13 600 m3,and the effective water depth is designed to be 16.3 m,and a fully underground gravity-inlet special-shaped reinforced concrete storage tank is adopted.The construction land area is 1 161.8 m2,and the land use index of the storage tank is only 0.085 m2/m3.The storage tank is emptied by a"high and low head matching"pump lifting method,and the designed emptying time is 24 h.The deodorization adopts a combined process of"water washing+ion oxygen+chemical filler adsorption",with a designed air volume of 35 000 m3/h,and the deodorization device is placed in the underground equipment interlayer.In view of the complex surrounding environment and the risk of pressurized water,the engineering measures of"two walls in one"underground diaphragm wall and metro jet system(MJS)rotary jet pile horizontal partition are adopted.According to calculations,the storage tank can reduce the stormwater pollutant to 295.8 tons of CODCr,236.6 tons of SS,22.2 tons of TN and 1.8 tons of TP per year,which have good environmental,social and economic benefits.This case can provide a certain reference for other projects of the same type.关键词
初雨调蓄池/全地下式/复杂地块/面源污染/地下连续墙Key words
initial rainwater storage tank/full underground type/complex land parcel/non-point source pollution/underground diaphragm wall分类
建筑与水利
