DE-IONIZER

Typical Number in Hospital: 20

Cost Bands: 2

References: 3

Impurities in water may be removed by a water softener or by a de-ionizer. These are most commonly encountered in connection with haemodialysis in which the concentration and composition of the dialysing fluid is extremely important, particularly if the life of the patient is sustained by haemodialysis for long periods. A de-ionizer is required in place of a water softener if there are significant quantities of calcium or magnesium in the domestic water supply. Aluminium levels exceeding 0.06 ppm can also cause serious disorders following long-term dialysis.

The de-ionizer employs an ion exchange resin column through which the water passes and this must be returned to the manufacturer or replaced at frequent intervals, which is relatively expensive. Automatic changeover systems also exist.