XUJia-hui,ZHAIHong-yan,SUNLing,et al.Algal Characteristics and Deposition in Regulating Tank of a Terminal Pumping Station Belonged to the South-to-North Water Diversion Project[J].China Water & Wastewater,2024,40(13):34-42.
Algal Characteristics and Deposition in Regulating Tank of a Terminal Pumping Station Belonged to the South-to-North Water Diversion Project
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第40卷
Number:
第13期
Page:
34-42
Column:
Date of publication:
2024-07-01
- Keywords:
- South-to-North Water Diversion Project; algae; sediment; regulating tank; water supply safety
- Abstract:
- The current deposition of sediment with high organic content in the regulating tank of a terminal pumping station belonged to the South-to-North Water Diversion Project has become an urgent operational problem, which has affected the stability of the water supply quality and the operational cost. However, quantitative analysis of the effect of algae on sediment deposition is rarely reported. In this study, the species and density of algae in the influent, inside, effluent and sediment of the regulating tank from April to October 2021 were investigated, and the algae mass and its contribution to the suspended solids and sediment were estimated. Bacillariophyta was the dominant algal species in the Yangtze River raw water, followed by Chlorophyta and Cyanophyta. From June to September, the algal densities in the influent, inside and effluent of the regulating tank were as high as 2.10×106-2.73×106 cells/L, 5.50×105-4.20×106 cells/L and 1.06×106-1.22×106 cells/L, respectively. The maximum mass concentration of algal cells in the influent, inside and effluent of the regulating tank was 5.04 mg/L, 3.35 mg/L and 2.31 mg/L, respectively, and the mass concentration of the recorded algal cells in the sediment was 17-984 μg/g. The mass concentration of algal cells accounted for 2% to 77% (average 36%) of the suspended solids. Large amounts of algae remained in the tank. The mass concentration of algae retained in the regulating tank in summer was estimated to be 0.60-2.72 mg/L, accounting for 9.2%-52% of the suspended solids. The influent introduced ten to hundred tons of algal cells into the regulating tank at most during the 30 days high algae period in summer, and algal cells retained and proliferated in the regulating tank, which seriously affected the water quality and water supply safety.
Last Update:
2024-07-01