SAND TRAP Russian patent published in 1996 - IPC

FIELD: sewage treatment to remove mechanical impurities. SUBSTANCE: sand trap has straight channel with flow inlet and outlet at its ends and inclined bottom with trough for sand collection in the deepest part of the bottom, and device for sand removal. Installed above trough is circulating bubbling tube for producing circulation flow in cross-section of the channel. Secured to part of channel side wall adjacent to the part of bottom and to end face in which flow discharge device is installed, are interconnected to one another. Bubbling tubes are connected to the circulating bubbling pipe. In this case, the number of bubbling holes per running meter increases in direction from circulating bubbling pipe. Transverse bubbling tubes are installed between inlet device and end face of pan which is secured to side wall of sand trap. EFFECT: higher efficiency. 6 cl, 5 dwg