Electrodialysis on RO concentrate to improve water recovery in wastewater reclamation

摘要

With the increasing of high quality water demand and decreasing of operational cost, reverse osmosis (RO) is applied on drinking water production, wastewater recycling and industrial water treatment. However, there are still some drawbacks in the application of RO. One of the most important issues is the treatment of the concentrated waste drain from reverse osmosis due to the high salinity of RO concentrate. In wastewater treatment (WWT), this high salinity may disturb the treatment of wastewater and RO-concentrates are therefore often discharged in the environment after dilution with effluent of the WWT to meet discharge limits. To solve this problem, electrodialysis (ED) may play an important role: after desalination the RO-concentrate by ED further purification in the WWT becomes possible (Figure 1).