METHOD FOR REMOVING SAND IN SEDIMENTATION BASIN

摘要

PROBLEM TO BE SOLVED: To provide a method for removing sand where the frequencies of operations and stops of a feed water pump and a sand lifting pump are reduced as much as possible and a usual inexpensive pump can be used.SOLUTION: In a method for removing sand being a low pressure sand collecting system where: the operation of a sand lifting pump is started when the water surface of a sedimentation basin reaches a high water level or higher; the operation of the sand lifting pump is stopped when the water surface of the sedimentation basin reaches a low water level; the water level of the sedimentation basin is kept in a drained state; low pressure water fed from a feed water pump is jetted from a nozzle to the bottom surface of the sedimentation basin; earth and sand accumulated on the bottom surface of the sedimentation basin are flown into a main trough and collected in a sand collecting pit; and the collected earth and sand are pumped up with water by the sand lifting pump, the high water level of the sedimentation basin is set between the highest point and the lowest point in the main trough.SELECTED DRAWING: Figure 8