Experimental investigation on dye wastewater treatment with reverse electrodialysis reactor powered by salinity gradient energy

Abstract

A novel advanced oxidation process technology for organic wastewater treatment was proposed in this paper. The working principle is that a low-grade heat (LGH) is first converted into a salinity gradient energy (SGE), and then the SGE is converted into the degradation energy of organic pollutions by a reverse electrodialysis (RED) reactor. To verify the feasibility of converting a SGE into a degradation energy by a RED reactor, an experimental investigation of dye wastewater treatment with a RED reactor powered by SGE had been done. The results showed that the output current of RED reactor, operating parameters of electrode rinse solution (ERS) and degradation circulation modes have effects on the decolorization of acid orange 7 (AO7) dye wastewater. Under the present experimental conditions, after 20 min treatment, the decolorization efficiencies of AO7 dye wastewater for the independent degradation circulation mode reached 99.93% and 96.52% in the anodic and cathodic loops respectively, while that for the synergetic degradation circulation mode reached 82.85%.