System for the removal and automatic washing of sand in black, municipal and residual waters

摘要

The invention relates to an automatic desanding system (fig. 29). The design of the desanding tank structure induces the sand into a sedimentation chamber having a second sand removal chamber, which is provided with a sand collecting hopper having sensor systems that activate a pump depending on the weight difference between the displaced sand and liquid. The sand is deposited in said hopper and is then removed periodically by means of a removal system formed by several accessories, which include a nozzle and a tuyere. A high speed jet is formed therein when clarified water is pumped, said jet dragging water, sludge and sand into the tank by means of a float system that activates the butterfly valves with the purpose of draining and returning the diluted sludge while reasonably cleaning the sand. The pipes have fixing elements enabling movement thereof and reducing effort as the sand is being removed. To ensure its operation, the desanding device also has sliding gates and dumping plates provided with a hole. The desanding device works intermittently by means of a control system thereby achieving low energy consumption per kg. of removed sand.