Investigations with Electrodialysis Reversal for the Treatment of Surface Water to Make-Up Water

Abstract

Abstract In the Dutch power stations, boiler make-up water is nowadays prepared by treating drinking water with ion exchangers. A problem, however, is that drinking water is expensive in certain areas of the Netherlands. Therefore it seems to be attractive to prepare make-up water out of surface water with aid of electrodialysis reversal (EDR). The experiments with an EDR installation were carried out with different types of surface water. The process consists of three main stages: pretreatment of the surface water to meet the requirements set for feed water for the EDR unit desalination in the EDR unit post-treatment of product water (with ion exchangers) from the EDR unit to comply with the guidelines for make-up water. From experiments on pilot plant scale it could be concluded that a simple filtration step to remove suspended matter was sufficient to comply with the requirements set for feed water for the EDR unit. Further it was possible to desalt the surface water to a large extend (about 90% or mor...