Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30685
Physico-chemical Treatment of Tar-Containing Wastewater Generated from Biomass Gasification Plants

Authors: Vrajesh Mehta, Anal Chavan

Abstract:

Treatment of tar-containing wastewater is necessary for the successful operation of biomass gasification plants (BGPs). In the present study, tar-containing wastewater was treated using lime and alum for the removal of in-organics, followed by adsorption on powdered activated carbon (PAC) for the removal of organics. Limealum experiments were performed in a jar apparatus and activated carbon studies were performed in an orbital shaker. At optimum concentrations, both lime and alum individually proved to be capable of removing color, total suspended solids (TSS) and total dissolved solids (TDS), but in both cases, pH adjustment had to be carried out after treatment. The combination of lime and alum at the dose ratio of 0.8:0.8 g/L was found to be optimum for the removal of inorganics. The removal efficiency achieved at optimum concentrations were 78.6, 62.0, 62.5 and 52.8% for color, alkalinity, TSS and TDS, respectively. The major advantages of the lime-alum combination were observed to be as follows: no requirement of pH adjustment before and after treatment and good settleability of sludge. Coagulation-precipitation followed by adsorption on PAC resulted in 92.3% chemical oxygen demand (COD) removal and 100% phenol removal at equilibrium. Ammonia removal efficiency was found to be 11.7% during coagulation-flocculation and 36.2% during adsorption on PAC. Adsorption of organics on PAC in terms of COD and phenol followed Freundlich isotherm with Kf = 0.55 & 18.47 mg/g and n = 1.01 & 1.45, respectively. This technology may prove to be one of the fastest and most techno-economically feasible methods for the treatment of tar-containing wastewater generated from BGPs.

Keywords: lime, Biomass Gasification, activated carbon, coagulation-flocculation, alum, Tar-containing wastewater

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1084594

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3164

References:


[1] G. Sridhar, P. J. Paul and H. S. Mukunda, "Biomass derived producer gas as a reciprocating engine fuel-an experimental analysis," Biomass and Bioenergy, vol. 21, no. 1, pp. 61-72, July 2001.
[2] C. Z. Wu, H. Huang,, S. P. Zheng and X. L. Yin, "An economic analysis of biomass gasification and power generation in China," Bioresource Technology, vol. 83, no. 1, pp. 65-70, May 2002.
[3] P. Hasler and Th. Nussbaumer, "Gas cleaning for IC engine applications from fixed bed biomass gasification," Biomass and Bioenergy, vol. 16, no. 6, pp. 385-395, June 1999.
[4] M. Jayamurthy, S. Dasappa, P. J. Paul, G. Sridhar, H. V. Sridhar, H. S. Mukunda, N. K. S. Rajan, C. Brage, T. Liliedahl and K. SjÖstrÖm, "Tar characterization in new generation agro-residue gasifiers-cyclone and downdraft open top twin air entry systems," in Biomass gasification and pyrolysis, State of the art and Future Prospects, CPL press, UK, 1997, pp. 235-248.
[5] M.W. Rogers, "Gasification apparatus and method," U. S. Patent 0 176 36, Aug. 4, 2004.
[6] M. W. Fcok, "Toxicity of wastewater generated from gasification of woodchips," Technology Brief, Dept. Water & Env. Eng., Lund Inst. Tech., Denmark, 2002.
[7] T. Nissen, "Method for cleaning tar-bearing waste water and apparatus for performing said method," U. S. Patent 7396454, July 8, 2008.
[8] F. Lettner, H. Timmerer and P. Haselbacher, "Biomass gasification-State of the art description," Graz Univ. Tech.-Institute of thermal engineering, Dec. 2007.
[9] A. V. Bridgwater, AACM. Beenackers and K. Sipila. (1998). An assessment of the possibilities for transfer of european biomass gasification technology to china (part 1)
[Online Available].
[10] I. O. Asia and E. E. Akporhonor, "Characterization and physicochemical treatment of wastewater from rubber processing factory," Int. J. Phy. Sci. vol. 2, no. 3, pp. 61-67, Mar. 2007.
[11] H. Selcuk, "Decolorization and detoxification of textile wastewater by ozonation and coagulation processes," Dyes & Pigments. vol. 64, no. 3, pp. 217-222, Mar. 2005.
[12] APHA, AWWA and WEF Standard methods for the examination of water and wastewater, American Public Health Association, 21st ed. Washington D.C, 2005.
[13] Z. Sapci and B. Ustun, "The removal of color and COD from textile wastewater by using waste pumice," Electron. J. Environ. Agric. & Food Chem. vol. 2, no. 2, pp. 286-290, 2003.
[14] H. F. Berger, B. Rouge, H. W. Gehm, N. J. Annandale and A. J. Herbet, "Decolorizing kraft waste liquors," U. S. Patent 3 120 464, Feb. 4, 1964.
[15] B. Inanc, F. Ciner and I. Ozturk, "Colour removal from fermentation industry effluents," Water Sci. and Tech. vol. 40, no. 1, pp. 331-338, 1999.
[16] H. Asilian, Sh. M. Fard, A. Rezaei, S. B. Mortazavi and A. Khavanin, "The removal of color and COD from wastewater containing water base color by coagulation process," Int. J. Env. Sci. Tech. vol. 3, no. 2, pp. 153-157, Apr. 2006.
[17] H. A. Aziz, S. Alias, F. Assari and M. N. Adlan, "The use of alum, ferric chloride and ferrous sulphate as coagulants in removing suspended solids, colour and COD from semi-aerobic landfill leachate at controlled pH," Waste Manage. Res. vol. 25, no. 6, pp. 556-565, Dec. 2007.
[18] J. Dwyer, P. Griffiths and P. Lant, "Simultaneous colour and DON removal from sewage treatment plant effluent: Alum coagulation of melanoidin," Water Res. vol. 43, no. 2, pp. 553-561, Feb. 2009.
[19] A. E Ghaly, A. Snow and B. E. Faber, "Treatment of grease filter wash water by chemical coagulation," Canadian Biosystems Engineering. vol. 48, pp. 6.13-6.22, 2006.
[20] S. H. Mutlu, U. Yetis, T. Gurkan and L. Yilmaz, "Decolorization of wastewater of a baker-s yeast plant by membrane processes," Water Res. vol. 36, no. 3, pp. 609-616, Feb. 2002.
[21] A. Amokrane, C. Comel and J. Veron, "Landfill leachates pre-treatment by coagulation flocculation," Water Res. vol. 31, no. 11, pp. 2275-2282, Nov. 1997.
[22] J. C. Liu and C. S. Lien, "Pre-treatment of bakery wastewater by coagulation flocculation and dissolved air floatation," Water Sci. & Tech. vol. 43, no. 8, pp. 131-137, 2001.
[23] M. R. Jekel, "Interactions of humic acids and aluminium salts in the flocculation process," Water Res. vol. 20, no. 12, pp. 1535-1542, Dec. 1986.
[24] L. Caceres, "Comparison of lime and alum treatment of municipal wastewater," Water Sci. & Tech. vol. 27, no. 11, pp. 261-264, 1993.
[25] M. A. Zazouli and Z. Yousefi, "Removal of heavy metals from solid wastes leachates coagulation-flocculation process," J. App. Sci. vol. 8, no. 11, pp. 2142-2147, 2008.
[26] A. Ginos, T. Manios and D. Mantzavinos, "Treatment of olive mill effluents by coagulation-flocculation-hydrogen peroxide oxidation and effect on phytotoxicity," J. Hazard. Mater. vol. 133, no. 1-3, pp. 135- 142, May. 2006.
[27] T. A. Ozbelge, O. H. Ozbelge and S. Z. Baskaya, "Removal of phenolic compounds from rubber-textile wastewaters by physico-chemical methods," Chem. Engineering and Processing. vol. 41, no. 8, pp. 719- 730, Sep. 2002.
[28] C. Brasquet, E. Subrenat and P. Lecloirec, "Selective adsorption on fibrous activated carbon of organics from aqueous solution: correlation between adsorption and molecular structure," Water Sci. & Tech. vol. 35, no. 7, pp. 251-259, 1997.
[29] I. Vázquez, J. Rodríguez-Iglesias, E. Marañón, L. Castrillón and M. Álvarez, "Removal of residual phenols from coke wastewater by adsorption," J. Hazard. Mater. vol. 147, no. 1-2, pp. 395-400, Aug. 2007.