GB778859A - Improvements relating to methods of and apparatus for bringing liquids into contact with granular materials - Google Patents

Abstract

778,859. Purifying liquids. PERMUTIT CO., Ltd. Oct. 20, 1955 [Oct. 20, 1954], No. 30258/54. Class 46. The passage of liquid vertically through a bed of granular material such as ion-exchange material or activated carbon to purify the liquid or to regenerate or wash the material is interrupted from time to time, a liquid is introduced at one end of the bed-container to move the bed vertically as a whole, thereby leaving a space at the one end and expelling material at the other end, and fresh material is introduced into the space. Liquid to be treated is introduced at 6, Fig. 1, and treated liquid passes out at 8. When partially-treated liquid withdrawn as a sample at 35 indicates deterioration in the liquid condition the valves on 6 and 8 are closed. Thereupon liquid is introduced at 20 and drives the bed 4 before it, granular material being expelled through a now-open valve 22 and the driving liquid passing out through a ring of holes 14 and valve 18, opened at the same time as 22. After discharge of the top layer of the bed the valve controlling 20 and valve 22 are shut and fresh granular material is introduced at 24, displacing the liquid filling the granule-free space below the bed through the valve 18. The treatment process is then restarted. In Fig. 2 features 6, 8 and 20 are as before, but in this case the liquid introduced to move the bed carries the bed bodily with it and passes out with the expelled granular material at 22 so that features 14, 16 and 18 may be dispensed with. Fresh granular material is in this case introduced at 30 through a ring of holes 26, the displaced liquid passing out at 22. In either case the collecting device 8 may be at the bottom of the container. In Fig. 3 the liquid to be treated passes upwards from inlet 6 to outlet 8. Liquid for moving the bed downwards is introduced at 20 through pipe 10 and withdrawn at 8 ; expelled granular material passes out at 22. Fresh granular material is introduced at 24 and displaces the liquid filling the granulefree space above the bed through 20 and an outlet 38. In all cases the distribution device 20 may also act as the collecting device on the outlet 8, -appropriate connections being provided outside the bed. According to the Provisional Specification the outlet 22 in Figs. 1 and 2 may be replaced by a discharge pipe with an open mouth in the top of the bed, the pipe extending downwards from its mouth and outwards through the container wall.