On the fouling mechanism of polysulfone ultrafiltration membrane in the treatment of coal gasification wastewater

Abstract

Membrane fouling has been investigated by using a polysulfone ultrafiltration membrane with the molecular weight cutoff of 20 kDa to treat crushed coal pressurized gasification wastewater. Under the conditions of different feed pressures, the permeate flux declines and rejection coefficients of pollutants referring to three parameters (total organic carbon (TOC), chroma and turbidity) were studied. The membrane fouling mechanism was simulated with three classical membrane fouling models. The membrane image and pollutants were analyzed by scanning electron microscopy and gas chromatography-mass spectrography (GC-MS). The results indicate that the permeate flux decreases with volume reduction factor before reaching a constant value. The rejection coefficients were also measured: f_TOC = 70.5%, f_C = 84.9% and f_T = 91%. Further analysis shows that the higher the feed pressure is, the sooner the permeate flux reaches constant value and the more sharply the permeate flux declines. Constant flux indicates a nonlinear growth with feed pressure (P_F): when P_F equals 1.2 bar, the mark for the critical flux, slight membrane fouling occurs; when P_F exceeds 1.2 bar, cake layer pollution aggravates. Also the rejection coefficients of global pollutant increases slightly with P_F, suggesting the possibility of cake compression when P_F exceeds 1.2 bar. Through regression analysis, the fouling of polysulfone ultrafiltration membrane could be fitted very well by cake filtration model. The membrane pollutants were identified as phthalate esters and long-chain alkenes by GC-MS, and a certain amount of inorganic pollutants by X-ray photoelectron spectroscopy.

Key words： membrane fouling; ultrafiltration membrane; coal gasification wastewater; rejection coefficient

Acknowledgements

The research funding was provided by the National High Technology Research and Development Program of China. (Grant No. 2015AA050502: Research on the key technology of coal gasification and wastewater control)

References

1 Li H Q, Han H J, Du M A, Wang W. Removal of phenols, thiocyanate and ammonium from coal gasification wastewater using moving bed biofilm reactor. Bioresource Technology, 2011, 102(7): 4667–4673

2 Li H Q, Han H J, Du M A, Wang W. Inhibition and recovery of nitrification in treating real coal gasification wastewater with moving bed biofilm reactor. Journal of Environmental Sciences (China), 2011, 23(4): 568–574

3 Liu D M, Liu Z H L, Li Y Y. Distribution and occurrence of polycyclic aromatic hydrocarbons from coal combustion and coking and its impact on the environment. Energy Procedia, 2011, 5(5): 734–741

4 Burmistrz P, Burmistrz M. Distribution of polycyclic aromatic hydrocarbons in coke plant wastewater. Water Science and Technology, 2013, 68(11): 2414–2420

5 Zhang W, Wei C, Yan B, Feng C, Zhao G, Lin C, Yuan M, Wu C, Ren Y, Hu Y. Identification and removal of polycyclic aromatic hydrocarbons in wastewater treatment processes from coke production plants. Environmental Science and Pollution Research International, 2013, 20(9): 6418–6432

6 Luthy R G, Stamoudis V C, Campbell J R, Harrison W. Removal of organic contaminants from coal conversion process condensates. Water Pollution Control Federation, 1983, 55(2): 196–207

7 Qian Y, Wen Y, Zhang H. Efficiency of pre-treatment methods in the activated sludge removal of refractory compounds in coke-plant wastewater. Water Research, 1994, 28(3): 701–710

8 Zhang M, Tay J H, Qian Y, Gu X S. Coke plant wastewater treatment by fixed biofilm system for COD and NH₃-N removal. Water Research, 1998, 32(2): 519–527

9 Yu H Q, Gu G W, Song L P. The effect of fill mode on the performance of sequencing-batch reactors treating various wastewaters. Bioresource Technology, 1996, 58(1): 46–55

10 Yu H Q, Yang C Y, Zhang H. The study on PAC leading in UF removing NOM of water. Membrane Science and Technology, 2009, 29(6): 85–89 (in Chinese)

11 Lee M W, Park J M. Biological nitrogen removal from coke plant wastewater with external carbon addition. Water Environment Research, 1998, 70(5): 1090–1095

12 Li Y M, Gua G W, Zhao J F, Yu H Q, Qiu Y L, Peng Y Z. Treatment of coke-plant wastewater by biofilm systems for removal of organic compounds and nitrogen. Chemosphere, 2003, 52(6): 997–1005

13 Marañón E, Vázquez I, Rodríguez J, Castrillón L, Fernández Y, López H. Treatment of coke wastewater in a sequential batch reactor (SBR) at pilot plant scale. Bioresource Technology, 2008, 99(10): 4192–4198

14 Giménez J B, Robles A, Carretero L, Duran F, Ruano M V, Gatti M N, Ribes J, Ferrer J, Seco A. Experimental study of the anaerobic urban wastewater treatment in a submerged hollow-fibre membrane bioreactor at pilot scale. Bioresource Technology, 2011, 102(19): 8799–8806

15 Ahmad A L, Sarif M, Ismail S. Development of an integrally skinned ultrafiltration membrane for wastewater treatment: Effect of different formulations of PSf/NMP/PVP on flux and rejection. Desalination, 2005, 179(1-3): 257–263

16 Wintgens T, Melin T, Schäfer A I, Muston M, Bixio D, Thoeye C. The role of membrane processes in municipal wastewater reclamation and reuse. Desalination, 2005, 178(1-3): 1–11

17 Ajmani G S, Goodwin D, Marsh K, Marsh K, Fairbrother D H, Schwab K J, Jacangelo J G, Huang H O. Modification of low pressure membranes with carbon nanotube layers for fouling control. Water Research, 2012, 46(17): 5645–5654

18 Tian J Y, Ernst M, Cui F Y, Jekel M. Correlations of relevant membrane foulants with UF membrane fouling in different waters. Water Research, 2013, 47(3): 1218–1228

19 Mallevialle J, Odendaal P E, Wiesner M R. Water Treatment Membrane Processes.New York: McGraw-Hill, 1996, 31–32

20 Bruggen B V, Lejon L, Vandecasteele C. Reuse, treatment and discharge of the concentrate pressure-driven membrane processes. Environmental Science & Technology, 2003, 37(17): 3733–3738

21 Magara Y, Kunikane S, Itoh M. Advanced membrane technology for application to water treatment. Water Science and Technology, 1998, 37(10): 91–99

22 Wen X, Zhou Z, Wei G, Zhang N. Experimental study on advanced treating process of coking wastewater by UF and RO. Technology of Water Treatment, 2010, 36(3): 93–96

23 Ma M, Jing D. Research on immersed UF-RO combined technological processes of recycling coal-gasification wastewater. . Journal of Tianjin Institute of Urban Construction, 2009, 15(4): 280–284

24 Karakulski K, Morawski W A, Grzechulska J. Purification of bilge water by hybrid ultrafiltration and photocatalytic processes. Separation and Purification Technology, 1998, 14(1-3): 163–173

25 Luo M, Wang Z S. Studies on the dentification and mechanism of the nanofiltration membrane fouling. Technology of Water Treatment, 1998, 24(6): 318–323 (in Chinese)

26 Yu H Q, Yang C Y, Zhang H. The study on PAC leading in UF removing NOM of water. Membrane Science and Technology, 2009, 29(6): 85–89 (in Chinese)

27 Yiantsios S G, Karabelas A J. An experimental study of humid acid and powdered activated carbon deposition on UF membranes and their removal by back washing. Desalination, 2001, 140(2): 195–209

28 MEP. Determination Methods for Examination of Water and Wastewater.Beijing: China Environmental Science Press, 2003: 1–213 (in Chinese)

29 Hermia J. Constant pressure blocking filtration laws—application to power-law non-newtonian fluids. Chemical Engineering Research & Design, 1982, 60: 183–187

30 Gonsalves V E. Recueil Des Travaux Chimiques Des Pays-Bas. Journal of the Royal Netherlands Chemical Society, 1950, 69: 873

31 Field R W, Wu D, Howell J A, Gupta B B. Critical flux concept for microfiltration fouling. Journal of Membrane Science, 1995, 100(3): 259–272

32 Defrance L, Jaffrin M Y. Comparison between filtrations at fixed transmembrane pressure and fixed permeate flux: Application to a membrane bioreactor used for wastewater treatment. Journal of Membrane Science, 1999, 152(2): 203–210

33 Choo K H, Lee C H. Membrane fouling mechanisms in the membrane-coupled anaerobic bioreactor. Water Research, 1996, 30(8): 1771–1780

34 Benítez F J, Acero J L, Leal A I. Treatment of wastewaters from the cork process industry by using ultrafiltration membranes. Desalination, 2008, 229(1-3): 156–169

35 Pillay V L, Buckley C A. Cake formation in cross-flow microfiltration systems. Water Science and Technology, 1992, 25(10): 149–162

36 Benítez F J, Acero J L, Leal A I. Application of microfiltration and ultrafiltration processes to cork processing wastewaters and assessment of the membrane fouling. Separation and Purification Technology, 2006, 50(3): 354–364

37 Xu H, Chen W, Sun M. Effect of two pretreatment techniques on preventing membrane fouling. Journal of Civil. Architectural & Environmental Engineering, 2012, 34(1): 108–112 (i<?Pub Caret?>n Chinese)

38 Lai P, Zhao H, Ye Z, Ni J. Assessing the effectiveness of treating coking effluents using anaerobic and aerobic biofilms. Process Biochemistry, 2008, 43(3): 229–237

39 Wang W, Han H J, Yuan M, Li H, Fang F, Wang K. Treatment of coal gasification of wastewater by a two continuous UASB system with step-feed for COD and phenols removal. Bioresource Technology, 2011, 102(9): 5454–5460