GB1497082A - Ion exchange process and apparatus - Google Patents

Abstract

1497082 Ion-exchange HAGER & ELSASSER 21 Jan 1975 [24 Jan 1974] 2590/75 Heading B1J In a process for cyclic operation of an ion exchange mixed bed installation, the ion exchange masses through which the untreated water flows are batchwise and cyclically fed to a back-rinsing column, then to a system in which regeneration and washing is effected and thence returned to a treatment container, the drainage in the back-rinsing column occurring by means of drainage pipes which extend downwardly in the back-rinsing column from the upper end thereof separating the ion exchange masses in the back rinse column into a cation exchanger mass, a mixture of cation and anion exchanger masses, and an anion exchanger mass respectively along and simultaneously with contaminations being rinsed out, the cation and anion exchanger masses then being separately drawn off, through said pipes, conveyed into separate containers for washing and regeneration purposes and then again admixed prior to re-use, and said drainage pipes have their ion exchange mass entry openings set at such a spacing from one another that the exchanger mass present between the levels of said openings amounts to a multiple of the respectively cyclically conveyed ion exchanger masses. As shown, 26 indicates the back-rinse column; the denser resin, usually the cation exchanger, is removed by pipe 30; the whole bed descends and the less dense resin usually the anionexchanger, is then withdrawn by pipe 28. 18 represents a measuring column the volume of which-one "charge"-is the volume of resin moved at one time. In a preferred embodiment the back-rinse column has a volume of 10 charges and normally holds 5 charges of resin; the volume between the ends of the pipes 28 and 30 is three charges. After regeneration the resins are introduced into column 41 to be thoroughly re-mixed before admission to column 10 in which the ionexchange process takes place.