Efficiency of sand filter device on reducing water turbidity in rivers

In recent years, it has been an increased demand for ecological and high-quality development, and urban water environment management has gradually shifted its focus from "water quality improvement" to "enhancing the clarity of water bodies." Currently, there are many technologies available for improving water clarity, but for urban water bodies, it is difficult to meet the needs for cost-effectiveness, ecological excellence, and minimal land use all at once. This paper describes the design of a small-scale filter device and presents the results of a water purification experiment aimed at reducing water turbidity, conducted on-site at a typical river in Shanghai. The main findings of the study areas follows: The filter device primarily utilizes quartz sand with a particle size of 2-4mm as the core filter material. When the operational flow rate is adjusted to 0.4 m ³ /h, the turbidity removal effect is significant, with the effluent turbidity stabilizing between 5-12 NTU, the turbidity reduction rate remaining stable at 60-70%, and the clear water production capacity per unit area reaching 12.7 m/h. The purification efficiency of the filter device per unit area is 328.0 NTU·m/h.