SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2020, Vol. 28 ›› Issue (1): 122-135.DOI: 10.1016/j.cjche.2019.07.011

• Separation Science and Engineering • Previous Articles     Next Articles

Investigation on removing recalcitrant toxic organic polluters in coking wastewater by forward osmosis

Zhiqiang Li1, Lanying Jiang1,2,3, Chongjian Tang1   

  1. 1 School of Metallurgy and Environment, Central South University, Changsha 410000, China;
    2 National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410000, China;
    3 Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410000, China
  • Received:2019-05-06 Revised:2019-06-17 Online:2020-03-31 Published:2020-01-28
  • Contact: Lanying Jiang

Investigation on removing recalcitrant toxic organic polluters in coking wastewater by forward osmosis

Zhiqiang Li1, Lanying Jiang1,2,3, Chongjian Tang1   

  1. 1 School of Metallurgy and Environment, Central South University, Changsha 410000, China;
    2 National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410000, China;
    3 Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410000, China
  • 通讯作者: Lanying Jiang

Abstract: Investigation was made on the efficiency of two commercial membranes in removing via forward osmosis (FO) the low molecular weight organic compounds typical of coking wastewater. The membranes were supplied by Poten and HTI companies. The organics in the simulated coking water were indole and pyrridine. Under FO mode, the rejection to the organics by Poten membrane was around 50%, whereas that for HTI membrane was obviously higher, ranging from 65% to 74%. The response of the two membranes in terms of Water flux and reverse salt flux (RSF) towards changing feed/draw solution (DS) flow rates in FO mode showed similar tendency, but different degree. Generally, the flux in FO using HTI membranes was lower. For HTI membrane, FO operated with pressure retarded osmosis (PRO) mode was also performed and the overall rejection of the organics was slightly lower than that in FO mode. In the long term FO test within 15 days, both Poten and HTI membranes displayed flux reduction and rejection enhancement. But the variation with Poten membrane was much more obvious. Discussion was carried out about the reasons and the mechanisms behind the FO performance difference between two membranes and the variation in flux and rejection with operation conditions. Characterizations by SEM, FTIR, AFM, XRD and XPS were tried to support the proposed explanations.

Key words: Coke wastewater, Organics rejection, Forward osmosis, Water flux, Reverse salt flux

摘要: Investigation was made on the efficiency of two commercial membranes in removing via forward osmosis (FO) the low molecular weight organic compounds typical of coking wastewater. The membranes were supplied by Poten and HTI companies. The organics in the simulated coking water were indole and pyrridine. Under FO mode, the rejection to the organics by Poten membrane was around 50%, whereas that for HTI membrane was obviously higher, ranging from 65% to 74%. The response of the two membranes in terms of Water flux and reverse salt flux (RSF) towards changing feed/draw solution (DS) flow rates in FO mode showed similar tendency, but different degree. Generally, the flux in FO using HTI membranes was lower. For HTI membrane, FO operated with pressure retarded osmosis (PRO) mode was also performed and the overall rejection of the organics was slightly lower than that in FO mode. In the long term FO test within 15 days, both Poten and HTI membranes displayed flux reduction and rejection enhancement. But the variation with Poten membrane was much more obvious. Discussion was carried out about the reasons and the mechanisms behind the FO performance difference between two membranes and the variation in flux and rejection with operation conditions. Characterizations by SEM, FTIR, AFM, XRD and XPS were tried to support the proposed explanations.

关键词: Coke wastewater, Organics rejection, Forward osmosis, Water flux, Reverse salt flux