Zero Liquid Discharge and Resource Treatment of Low-Salinity Mineralized Wastewater Based on Combing Selectrodialysis with Bipolar Membrane Electrodialysis

Separations

article

Xueting Zhao¹  Xinhao Cheng¹  Jinshan Sun¹  Jialin Liu¹  Zhaofeng Liu²  Yali Wang³  Jiefeng Pan¹ 

[1]College of Chemical Engineering, Zhejiang University of Technology

[2]State Key Laboratory of Water Resource Protection and Utilization in Coal Mining

[3]Department of Chemistry and Chemical Engineering, Yulin University

关键词: selectrodialysis;    bipolar membrane electrodialysis;    mineralized wastewater;    recovery;    influence factors;   

DOI  :  10.3390/separations10040269

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

A large amount of mine water is generated during coal production, which not only damages the surface environment and ecology but also wastes groundwater resources in the mining area, exacerbating regional water scarcity. In this work, a novel zero liquid discharge technology combining selectrodialysis (SED) and bipolar membrane electrodialysis (BMED) was developed for the resourceful treatment of low-salinity mineralized wastewater. The SED stack had demonstrated to be workable for the elimination of multivalent ions. The BMED stack converts brine into acid and base. After SED, a high pure crude salt (~98%) was attained. Furthermore, under the conditions of a current density of 20 mA/cm2, a flow velocity of 20 L/h, and an initial acid/base concentration of 0.10 mol/L, the maximum concentrations of acid and base were found to be 0.75 mol/L and 0.765 mol/L, respectively, for a feed conductivity of 55 mS/cm. The cost of the entire electrodialysis stage was evaluated to be USD 1.38/kg of NaOH. Therefore, this combined UF-RO-SED-BMED process may be an effective strategy for the sustainable treatment of low-salinity mineralized wastewater.

【 授权许可】

CC BY