| 摘要 |
PROBLEM TO BE SOLVED: To perform sand collection under a low pressure even in a constant flow state with low energy consumption and high efficiency concerning a sand collection device and sand collection method in a wastewater sand basin.SOLUTION: A plurality of sand basins are installed in parallel in a flow direction of wastewater. Each sand basin is formed with a sand collection pit 20 on a bottom surface. In order to perform sand collection through a low pressure sand collection system while constantly maintaining the flow of wastewater, an entrance gate 12 is disposed at an inflow side to individually block the inflow of wastewater into a sand basin 10, and an exit gate 14 is disposed at an outflow side to separate the sand basin where sand is being collected from another sand basin where wastewater flows through. When a flow rate is low at nighttime or the like, the entrance gate 12 and the exit gate 14 of only one sand basin 10 are closed, and sedimentary sand accumulated in the sand basin 10 is collected into the sand collection pit 20 with water sprayed through nozzles 26, and the collected sand is discharged with a sand lifting pump 32 to execute sand collection. |
