Evaluation of scaling prevention in reverse osmosis membranes by anodic zinc addition and magnetic fields

Abstract

South Africa will experience a water crisis in the near future and the supply will not be able to meet the demand. One of the ways to solve this problem is the desalination of brackish water (groundwater). However, during this desalination process, salts can precipitate on the membrane surface, which leads to a decrease in the permeate quality (% salt rejection) and a decrease in flow per unit area of the permeate (flux). This phenomenon is called fouling. There are four categories of membrane fouling: scale, silt, bacteria and organic material. Scale has locally been found to be the greatest problem associated with groundwater desalination by Reverse Osmosis (RO) due to the occurrence of unwanted particles on the membrane surface that cause the membrane to clog or to be choked. Fortunately, the unwanted salt precipitates and other unwanted material on the membrane surface can be removed by using anti-scaling agents/chemicals.