GB870617A - Salt purification, reclaimation and treatment plant - Google Patents

Abstract

870,617. Washing granular materials. ROSSI, A. J. July 14, 1958 [July 16, 1957], No. 22500/58. Class 82(2) A plant for washing granular materials such as common salt comprises a separating cone 2, an overflow duct 4, a lower discharge opening connected to an entraining flow conduit 8 leading to a transverese passage which has an opposite inlet and outlet 8a and 8b, and flow displacing means such as a perforated pipe or ring 28 and a rotary valve 7 located in the bottom of the cone or in the flow conduit. The inlet 8a is connected to the discharge pipe 9 of a pump 10 and the outlet 8b discharges onto a tilted screen 12 located over a tilted settling tank 6 which is divided into three sections 6a, 6d and 6e The tank 6 is charged with brine which is conditioned by conditioning agents such as soda ash, caustic soda and aluminium sulphate in box 16 and the brine is circulated by pump 10 via conduit 8 to the cone 2 where it contacts the granular material such as salt. Impurities are floated off at 4 to a gutter 5 and rotation of valve 7 at 12 to 24 r.p.m: allows the washed salt to discharge into conduit 8 from where it is carried by the brine to screen 12, washed by sprays 14 from pump 10 and then discharged at 13. Rotation of valve 7 causes an intermitent upward flow of brine into cone 2 and an increased turbulence is effected by forcing compressed air or brine raising liquor through perforated ring 28.