GB378890A - Improvements in sedimentation apparatus - Google Patents

Abstract

378,890. Gravity-separation apparatus. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.- (Dorr Co. ; 247, Park Avenue, New York, U.S.A.) April 13, 1931, No. 10880. [Class 111.] A device for scraping sludge from the bottom of a settling-tank is actuated by a traveller which moves round the circumference of the tank and has means for counteracting the lateral pull of the scraper. Fig. 1 shows a settling-tank having the bottom in the form of hoppers 16 with sludge outlets 13. The scraper consists of chains suspended in loops 45 from a cable 26, the ends of which are connected to carriers T, Fig. 6, suspended from a rail 17, and moved along it by a chain 20 which is driven by a sprocket 22 and passes round idler pulleys 21. Auxiliary chain loops may be provided near the ends of the cable 26 and all the loops may be stiffened by wire rope 49. Each carrier T comprises rollers 25, pivoted members 27, 28 to which the chain 20 is attached, a frame 34 to receive weights 35, and a clevis 33 for attachment of the cable 26. The frame 34 can move relatively to the supporting member 28 so as to prevent undue strain on the chain 20 when the traveller passes round a corner of the tank. The clevis also supports a rod 40 carrying an adjustable counterweight, which serves to steady the cable. Fig. 7 shows a rectangular tank with sludge outlets 54, 55, a short distance from the centre at which the mid point of the cable 26 is held by a rotatable collar. Fig. 9 shows a scraper built up of wooden blocks 68 connected by flexible strips 70.