For hydropower stations, they all need sand and gravel processing systems for concrete demand. On the one hand, rocks will be broken to provide sands. On the other hand, machine-made sands are used to make concrete. The two system complement each other. This not only optimizes natural resources, but also greatly saves operating costs. While hydropower stations building, the designed stone aggregate might be 1000 tons per hour. Due to the huge production capacity, huge amount of sand washing wastewater and concrete wastewater will be generated during the entire construction process. In order to fully save resources and protect the environment, water supply and drainage system, and wastewater treatment system are also required. And the both are also important parts.
Generally, for machine-made sand wastewater, the general process flow is: mechanical pretreatment - radial flow sedimentation tank - filter press for sludge dewatering. As for the wastewater of the concrete production system, the process normally adopts "coagulant and precipitation". After pretreatment, the final sludge will be dehydrated by plate and frame filter presses, and can realize dry stack. According to that, more than 70% of water resources can be recycled. And the drainage standard can meet the Chinese first-level discharge requirements or achieve zero discharge.