SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2020, Vol. 28 ›› Issue (7): 1911-1917.DOI: 10.1016/j.cjche.2019.08.001

• Energy, Resources and Environmental Technology • 上一篇    下一篇

Acid precipitation coupled membrane-dispersion advanced oxidation process (MAOP) to treat crystallization mother liquor of pulp wastewater

Rongzong Li, Zhaoyang Li, Qian Jiang, Zhaoxiang Zhong, Ming Zhou, Weihong Xing   

  1. State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
  • 收稿日期:2019-06-18 修回日期:2019-07-30 出版日期:2020-07-28 发布日期:2020-08-31
  • 通讯作者: Ming Zhou, Weihong Xing
  • 基金资助:
    Financial supports from the Prospective Joint Research Project of Jiangsu Province (BY2014005-06), National Natural Science Foundation of China (U1510202), and the Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM) are gratefully acknowledged.

Acid precipitation coupled membrane-dispersion advanced oxidation process (MAOP) to treat crystallization mother liquor of pulp wastewater

Rongzong Li, Zhaoyang Li, Qian Jiang, Zhaoxiang Zhong, Ming Zhou, Weihong Xing   

  1. State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
  • Received:2019-06-18 Revised:2019-07-30 Online:2020-07-28 Published:2020-08-31
  • Contact: Ming Zhou, Weihong Xing
  • Supported by:
    Financial supports from the Prospective Joint Research Project of Jiangsu Province (BY2014005-06), National Natural Science Foundation of China (U1510202), and the Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM) are gratefully acknowledged.

摘要: Treatment to crystallization mother liquor containing high concentration of organic and inorganic substances is a challenge in zero liquid discharge of industrial wastewater. Acid precipitation coupled membrane-dispersion advanced oxidation process (MAOP) was proposed for organics degradation before salt crystallization by evaporation. With acid-MAOP treatment CODCr in mother liquor of pulping wastewater was eliminated by 55.2% from ultrahigh initial concentration up to 12,500 mg·L-1. The decolorization rate was 96.5%. Recovered salt was mainly NaCl (83.3 wt%) having whiteness 50 brighter than industrial baysalt of whiteness 45. The oxidation conditions were optimized as CO3 = 0.11 g·L-1 and CH2O2 = 2.0 g·L-1 with dispersing rate 0.53 ml·min-1 for 100 min reaction toward acidified liquor of pH = 2. Acidification has notably improved evaporation efficiency during crystallization. Addition of H2O2 made through membrane dispersion has eliminated hydroxyl radical “quench effect” and enhanced the degradation capacity, in particular, the breakage of carbon-chloride bonds (of both aliphatic and aromatic). As a result, the proposed coupling method has improved organic pollutant reduction so as the purity of salt from the wastewater mixture which can facilitate water and salt recycling in industry.

关键词: Advanced oxidation process, Crystallization mother liquor, Ceramic membrane dispersion, Pulping wastewater

Abstract: Treatment to crystallization mother liquor containing high concentration of organic and inorganic substances is a challenge in zero liquid discharge of industrial wastewater. Acid precipitation coupled membrane-dispersion advanced oxidation process (MAOP) was proposed for organics degradation before salt crystallization by evaporation. With acid-MAOP treatment CODCr in mother liquor of pulping wastewater was eliminated by 55.2% from ultrahigh initial concentration up to 12,500 mg·L-1. The decolorization rate was 96.5%. Recovered salt was mainly NaCl (83.3 wt%) having whiteness 50 brighter than industrial baysalt of whiteness 45. The oxidation conditions were optimized as CO3 = 0.11 g·L-1 and CH2O2 = 2.0 g·L-1 with dispersing rate 0.53 ml·min-1 for 100 min reaction toward acidified liquor of pH = 2. Acidification has notably improved evaporation efficiency during crystallization. Addition of H2O2 made through membrane dispersion has eliminated hydroxyl radical “quench effect” and enhanced the degradation capacity, in particular, the breakage of carbon-chloride bonds (of both aliphatic and aromatic). As a result, the proposed coupling method has improved organic pollutant reduction so as the purity of salt from the wastewater mixture which can facilitate water and salt recycling in industry.

Key words: Advanced oxidation process, Crystallization mother liquor, Ceramic membrane dispersion, Pulping wastewater