COUNTERCURRENT REGENERATION PROCESS

摘要

A method of regenerating an ion exchanger which is used to treat a solution introduced to the ion exchanger in a downward charging direction. The ion exchanger comprises a non-constrained bed of ion exchange material in the form of ion exchange granules and has a concentration profile through the ion exchange material after the solution has been introduced to the ion exchanger in the charging direction. The method in one embodiment comprises passing a regenerating solution upwardly through the non-constrained bed of ion exchange material in an intermittent pulsed flow comprising a pulse or up flow of regenerating solution, a subsequent non-flow pause time, followed by a down flow pulse in a direction opposite to the up flow. The duration and velocity of the pulse or up flow of regenerating solution is sufficient to hydrodynamically lift the ion exchange granules A controlled distance through all of the ion exchange granules without causing significant mixing of ion exchange granules between different layers of the ion exchange material. The duration of the subsequent non-flow pause time being of short duration to allow for some perceptible settling of the ion exchange granules, with the down flow pulse being sufficient to reduce the sedimentation time of the ion exchange granules to a fraction of the normal settling time for the granules in the absence of the down flow pulse Docket 4011 50630