Ion exchange filter - has regenerating liq. drainage fittings with liq. permeable sidewalls

摘要

Ion exchange filter has a resin filling above a particle bed, a regenerating liq. distributor within the bed and a regenerating liq. withdrawal system with liq. permeable regions located at least predominantly below the resin filling surface. The bed consists of porous consolidated material and that the withdrawal system consists of drainage fittings distributed over the cross-section of the filter vessel and connector to a collector pipe, the fittings being impermeable to resin particles but having sides permeable to liqs. and gases so that the liq. permeable area increases with rising liq. level. Process for regenerating the resin filling of the ion exchange filter is also claimed. ADVANTAGE - Gives improved flow distribution of the regenerating liq. and wash water and thus better liq. utilisation, without being affected by slight displacements of the withdrawal system. The drainage fittings have the same internal pressure as that in the gas space above the resin filling so that liq. flows into all the fittings under the same conditions. Any liq. level increase is compensated by the increased permeable area of the fittings and the fittings can be easily arranged or dimensioned to provide uniform liq. withdrawal over the entire filter cross-section.