Industrial application of grid flocculation double-layer inclined pipe sedimentation tank
A power plant used grid flocculation sedimentation tank to remove turbidity from make-up water of circulating cooling water system,for the purpose of solving the problem of too high liquid level load which can not meet the code requirement due to space restriction,by adding an additional layer of inclined pipes with a di-ameter of 50 mm and a diagonal length of 0.5 m in the sedimentation tank,a grid flocculation double-layer in-clined pipe sedimentation tank structure was formed,which not only achieved dual solid-liquid separation,but also extended hydraulic retention time,the theoretical calculation of suspended solids removal rate could be in-creased by 4.27%.After actual operation,the turbidity of the produced water remained stable below 5 NTU,and the cost per ton of water treatment chemicals was 0.29 yuan.However,there is a problem of inconvenient flush-ing of sediment in the lower inclined pipes,it is recommended to adjust the lower inclined pipes to inclined plates and configure automatic flushing facilities to solve this provlem when constructing grid flocculation dou-ble-layer inclined pipe sedimentation tanks in future projects.