GB542729A - Improvements in or relating to the washing of sand, gravel and the like - Google Patents

Abstract

542,729. Washing granular material. UNIFLOC REAGENTS, Ltd., and SAMUEL, J. O. June 17, 1940, No. 10497. [Class 82 (ii)] In an apparatus for washing sand, gravel &c. a feed vessel B into which the mixture of sand &c. and water is fed by a pipe S, is connected to a washing vessel A by a conduit C. A shaft M driven by a motor O is rotatably mounted on the three vessels and has mounted thereon at least one impeller G and also a spinner E provided with a serrated upper edge. Secured to the lower edge of an adjustable frusto-conical base Z embracing the lower end of the vessel C is an annular plate D provided with two annular sets of pegs X and another impeller F is mounted on the shaft M below the spinner E. In use, the sand &c. mixed with water is fed into the vessel B, the vessel A being full of water and the spindle M revolving at high speed. When the spinner E gets up to speed, the water is forced by the blade of the impeller G against the sides of the conduit C and rises in the vessel B. As the sand continues to enter the conduit C it is retained by centrifugal action until the head of sand exceeds a certain figure when it discharges into the spinner E. The sand is then thrown violently and upwardly between the pegs X and finally washed sand settles and passes out through the outlet Y; the fines and impurities overflow at H. The rate at which water is passed through the apparatus may be controlled so that the amount of the suspended matter in the effluent is for example between 0.3 and 1 lb. per gallon as referred to in Specification 450,032 and is flocculated by the process described in Specification 435,126, [Group I], or by the use of flocculating gels produced as described in Specification 5'16,294, [Group I], the clarified water being returned to the washing apparatus. A small amount of deflocculating agent may be added to the washing water before use.