Sains Malaysiana 49(7)(2020): 1729-1743

http://dx.doi.org/10.17576/jsm-2020-4907-23

Syngas Production from Rubberwood Biomass in Downdraft Gasifier Combined with Wet Scrubbing: Investigation of Tar and Solid Residue

(Pengeluaran Singas daripada Biojisim Kayu Getah dalam Sistem Pengegas Alir Turun Digabungkan dengan Penggahar Basah: Kajian Tar dan Sisa Pepejal)

SYED HASEEB SULTAN¹, ARKOM PALAMANIT²*, KUA-ANAN TECHATO³, MUHAMMAD AMIN⁴, KHURSHID AHMED⁵& ASADULLAH⁴

¹Sustainable Energy Management Program, Faculty of Environmental Management, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand

²Interdisciplinary Graduate School of Energy Systems, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand

³Environmental Assessment and Technology for Hazardous Waste Management Research Center, Faculty of Environmental Management, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand

⁴Department of Chemical Engineering, Faculty of Engineering, BUITEMS, Quetta, Pakistan

⁵Molecular Biotechnology Laboratory, Department of Industrial Biotechnology, Faculty of Agro-Industry, Prince of Songkla University, Songkhla Province, Thailand

Diserahkan: 6 Oktober 2019/Diterima: 12 Mac 2020

Abstract

Production of synthesis gas by gasification is still a challenge due to the tar in the synthesis gas (syngas). This tar needs to be eliminated by appropriate methods before using the syngas as a fuel. Moreover, the solid residue after gasification also needs to be properly managed or destroyed. Therefore, the aim of this study was to investigate tar and solid residue generated by gasification of rubberwood biomass, including rubberwood chips (RWC), rubberwood pellets (RWP), rubberwood unburned char (UBC), and their blends, in a downdraft gasifier. Waste vegetable oil (WVO) and water were used as scrubbing media. Properties of the biomass samples were characterized by proximate and ultimate analysis, as well as for the higher heating value. The downdraft gasifier was operated at 850 °C and equivalence ratio (ER) of 0.25. The concentrations of tar in syngas both before and after passing through the wet scrubber were determined. Chemical compounds in the tar were analysed by GC-MS. The solid residue remaining after gasification was separated into biochar and ash. The biochar was characterized by CHNS/O analyser, FTIR, SEM, and for the iodine number. The compounds in ash were determined by XRF. The results show that biomass type and scrubbing media affected the tar removal efficiency. Scrubbing syngas with WVO had better tar removal efficiency than scrubbing with water. The highest tar removal efficiency with WVO was 82.16%. The tar sample consisted of complex compounds as indicated by GC-MS, and these compounds depended on type of biomass feedstock. The solid residue obtained after gasification process contained biochar (unburned carbon) and ash. Some biochars can be used as solid fuels, depending on carbon content and energy content. The biochar also had a highly porous structure based on SEM imaging, and a high iodine number (930-1134 mg/g). The biochar contained the functional groups OH, C-O, and C-H, as indicated by FTIR. CaO, K₂O, SiO₂, and MgO were the major components in ash. The spent WVO, biochar, and ash need to be properly managed or utilized for sustainable gasification operations, and these results support that pursuit.

Keywords: Biomass; gasification; rubberwood biomass; syngas cleaning; tar removal

ABSTRAK

Penghasilan gas sintesis melalui proses pengegasan masih mencabar kerana kehadiran tar dalam gas sintesis (singas). Tar ini perlu disingkirkan melalui kaedah yang bersesuaian sebelum singas digunakan sebagai bahan api. Selain itu, sisa pepejal yang terhasil selepas proses pengegasan juga perlu diuruskan atau dimusnahkan dengan betul. Oleh demikian, tujuan kajian ini adalah untuk mengkaji tar dan sisa pepejal yang terhasil daripada proses pengegasan biojisim kayu getah, termasuk serpihan kayu getah, pelet kayu getah, arang kayu getah dan campuran kesemua bahan dalam pengegas alir turun. Minyak sayur terpakai dan air telah digunakan sebagai media penggahar. Ciri-ciri sampel biojisim telah dikaji melalui analisis proksimat dan muktamad, dan juga nilai pemanasan tinggi. Sistem pengegas alir turun telah beroperasi pada suhu 850 °C and nisbah kesetaraan 0.25. Kandungan tar dalam singas sebelum dan selepas melalui media penggahar telah diukur. Sebatian kimia dalam sampel tar telah dianalisis menggunakan GC-MS. Sisa baki pepejal selepas proses pengegasan telah dipisah daripada arang bio dan abu. Arang bio telah dicirikan melalui alat CHNS/O, FTIR, SEM, dan nombor iodin. Sebatian dalam abu dianalisis melalui XRF. Keputusan yang diperoleh menunjukkan bahawa jenis biojisim dan media penggahar telah mempengaruhi keberkesanan penyingkiran tar. Penggaharan singas menggunakan minyak sayur terpakai menunjukkan keberkesanan yang lebih baik berbanding dengan air daripada segi penyingkiran tar. Setinggi 82.16% penyingkiran tar telah tercapai menggunakan minyak sayur terpakai. Sampel tar mengandungi sebatian yang kompleks seperti yang ditunjukkan oleh GC-MS dan komposisi sebatian ini bergantung kepada jenis biojisim. Sisa pepejal terhasil selepas proses pengegasan mengandungi arang bio (karbon tak terbakar) dan abu. Sesetengah arang bio boleh digunakan sebagai bahan api pepejal yang bergantung kepada kandungan karbon dan tenaga. Arang bio yang terhasil juga mempunyai struktur berongga berdasarkan imej SEM dan nilai iodin yang tinggi (930-1134 mg/g). Arang bio yang terhasil mengandungi kumpulan berfungsi OH, C-O dan C-H seperti yang ditunjukkan oleh FTIR. CaO, K₂O, SiO₂ dan MgO adalah kandungan utama dalam abu. Minyak sayur terpakai, arang bio dan abu yang telah digunakan perlu diuruskan dengan betul untuk operasi pengegasan yang mampan dan hasil ini menyokong usaha tersebut.

Kata kunci: Biojisim; biojisim kayu getah; pembersihan singas; pembuangan tar; pengegasan

RUJUKAN

Abdullahi, N., Sulaiman, F. & Safana, A.A. 2017. Bio-oil and biochar derived from the pyrolysis of palm kernel shell for briquette. Sains Malaysiana 46(12): 2441-2445.

Abdoulmoumine, N., Adhikari, S., Kulkarni, A. & Chattanathan, S. 2015. A review on biomass gasification syngas cleanup. Applied Energy 155: 294-307.

Ahmad, N.A. & Zainal, Z.A. 2016. Performance and chemical composition of waste palm cooking oil as scrubbing medium for tar removal from biomass producer gas. Journal of Natural Gas Science and Engineering 32: 256-261.

Amin, M., Chetpattananondh, P. & Ratanawilai, S. 2019. Application of extracted marine Chlorella sp. residue for bio-oil production as the biomass feedstock and microwave absorber. Energy Conversion and Management 195: 819-829.

Antonopoulos, I.S., Karagiannidis, A., Gkouletsos, A. & Perkoulidis, G. 2012. Modelling of a downdraft gasifier fed by agricultural residues. Waste Management 32: 710-718.

Anwar, Z., Gulfraz, M. & Irshad, M. 2014. Agro-industrial lignocellulosic biomass a key to unlock the future bio-energy: A brief review. Journal of Radiation Research and Applied Sciences 7(2): 163-173.

Awais, M., Li, W., Arshad, A., Haydar, Z., Yaqoob, N. & Hussain, S. 2018. Evaluating removal of tar contents in syngas produced from downdraft biomass gasification system. International Journal of Green Energy 15(12): 724-731.

Bamdad, H., Hawboldt, K. & MacQuarrie, S. 2018. A review on common adsorbents for acid gases removal: Focus on biochar. Renewable and Sustainable Energy Reviews 81: 1705-1720.

Basu, P. 2010. Biomass Gasification and Pyrolysis: Practical Design and Theory. 1st ed. New York: Academic Press.

Bensidhom, G., Hassen-Trabelsia, A.B., Alper, K., Sghairoun, M., Zaafouri, K. & Trabelsi, I. 2018. Pyrolysis of date palm waste in a fixed-bed reactor: Characterization of pyrolytic products. Bioresource Technology 247: 363-369.

Bhoi, P.R., Huhnke, R.L., Kumar, A., Payton, M.E., Patil, K.N. & Whiteley, J.R. 2015. Vegetable oil as a solvent for removing producer gas tar compounds. Fuel Processing Technology 133: 97-104.

Brammer, I.G. & Bridgwater, A.V. 2002. The influence of feed stock drying on the performance and economics of a biomass gasifier-engine CHP System. Biomass and Bioenergy 22(4): 271-281.

Chen, M., Yu, D. & Wei, Y. 2015. Evaluation on ash fusion behaviour of eucalyptus bark/lignite blends. Powder Technology 286: 39-47.

Corella, J., Caballero, M.A., Aznar, M.P. & Brage, C. 2003. Two advanced models for the kinetics of the variation of the tar composition in its catalytic elimination in biomass gasification. Industrial & Engineering Chemistry Research 42(13): 3001-3011.

Demirbaş, A. 2005. Thermochemical conversion of biomass to liquid products in the aqueous medium. Energy Source 27(13): 1235-1243.

Di Gregorio, F., Santoro, D. & Arena, U. 2014. The effect of ash composition on gasification of poultry wastes in a fluidized bed reactor. Waste Management & Research 32(4): 323-330.

Farzad, S., Mandegari, M.A. & Görgens, J.F. 2016. A critical review on biomass gasification, co-gasification, and their environmental assessments. Biofuel Research Journal 12: 483-495.

Fuentes-Cano, D., Von Berg, L., Diéguez-Alonso, A., Scharler, R., Gómez-Barea, A. & Anca-Couce, A. 2020. Tar conversion of biomass syngas in a downstream char bed. Fuel Processing Technology 199: 106271.

García, R., Pizarro, C., Lavín, A.G. & Bueno, J.L. 2013. Biomass proximate analysis using thermogravimetry. Bioresource Technology 139: 1-4.

Guo, Y. & Bustin, R. 1998. FTIR spectroscopy and reflectance of modern charcoals and fungal decayed woods: Implications for studies of inertinite in coals. International Journal of Coal Geology 37(1-2): 29-53.

Han, J. & Kim, H. 2008. The reduction and control technology of tar during biomass gasification/pyrolysis: An overview. Renewable and Sustainable Energy Reviews 12(2): 397-416.

Hossain, M.K., Strezov, V., Chan, K.Y., Ziolkowski, A. & Nelson, P.F. 2011. Influence of pyrolysis temperature on production and nutrient properties of wastewater sludge biochar. Journal of Environmental Management 92(1): 223-228.

Islam, M.W. 2020. A review of dolomite catalyst for biomass gasification tar removal. Fuel 267: 117095.

Jadhav, A., Ahmed, I., Baloch, A.G., Jadhav, H., Nizamuddin, S., Siddiqui, M.T.H. & Mubarak, N.M. 2019. Utilization of oil palm fronds for bio-oil and bio-char production using hydrothermal liquefaction technology. Biomass Conversion and Biorefinery. https://doi.org/10.1007/s13399-019-00517-y.

James, A.K., Thring, R.W., Helle, S. & Ghuman, H.S. 2012. Ash management review-Applications of biomass bottom ash. Energies 5(10): 3856-3873.

Jia, S., Ning, S., Ying, H., Sun, Y., Xu, W. & Yin, H. 2017. High quality syngas production from catalytic gasification of woodchip char. Energy Conversion and Management 151: 457-464.

Jindo, K., Mizumoto, H., Sawada, Y., Sanchez-Monedero, M.A. & Sonoki, T. 2014. Physical and chemical characterization of biochars derived from different agricultural residues. Biogeosciences 11(23): 6613-6621.

Johari, A., Mat, R., Alias, H., Hashim, H., Hassim, M.H., Zakaria, Z.Y. & Rozainee, M. 2014. Combustion characteristics of refuse derived fuel (rdf) in a fluidized bed combustor. Sains Malaysiana 43(1): 103-109.

Kaewluan, S. & Pipatmanomai, S. 2011a. Gasification of high moisture rubber woodchip with rubber waste in a bubbling fluidized bed. Fuel Processing Technology 92(3): 671-677.

Kaewluan, S. & Pipatmanomai, S. 2011b. Potential of synthesis gas production from rubber wood chip gasification in a bubbling fluidised bed gasifier. Energy Conversion and Management 52(1): 75-84.

Kate, G.U. & Chaurasia, A.S. 2018. Gasification of rice husk in two-stage gasifier to produce syngas, silica and activated carbon. Energy Sources, Part A: Recovery, Utilization and Environmental Effects 40(4): 466-471.

Kirubakaran, V., Sivaramakrishnan, V., Nalini, R., Sekar, T., Premalatha, M. & Subramanian, P. 2009. A review on gasification of biomass. Renewable and Sustainable Energy Reviews 13(1): 179-186.

Khongphakdi, P., Palamanit, A., Phusunti, N., Tirawanichakul, Y. & Shrivastava, P. 2020. Evaluation of oil palm biomass potential for bio-oil production via pyrolysis processes. International Journal of Integrated Engineering 11(10): 45-52.

Ku, X., Jin, H. & Lin, J. 2017. Comparison of gasification performances between raw and torrefied biomasses in an air-blown fluidized-bed gasifier. Chemical Engineering Science 168: 235-249.

Kumar, P., Barrett, D.M., Delwiche, M.J. & Stroeve, P. 2009. Methods for pretreatment of lignocellulosic biomass for efficient hydrolysis and biofuel production. Industrial and Engineering Chemistry Research 48(8): 3713-3729.

Liang, M., Zhang, K., Lei, P., Wang, B., Shu, C.M. & Li, B. 2019. Fuel properties and combustion kinetics of hydrochar derived from co-hydrothermal carbonization of tobacco residues and graphene oxide. Biomass Conversion and Biorefinery 10: 189-201.

Li, C. & Suzuki, K. 2009. Tar property, analysis, reforming mechanism and model for biomass gasification-an overview. Renewable and Sustainable Energy Reviews 13(3): 594-604.

Li, F., Xu, M., Wang, T., Fang, Y. & Ma, M. 2015. An investigation on the fusibility characteristics of low-rank coals and biomass mixtures. Fuel 158: 884-890.

Lopez, G., Artetxe, M., Amutio, M., Alvarez, J., Bilbao, J. & Olazar, M. 2018. Recent advances in the gasification of waste plastics. A critical overview. Renewable and Sustainable Energy Reviews 82: 576-596.

Mckendry, P. 2002a. Energy production from biomass (part 2): Conversion technologies. Bioresource Technology 83(1): 47-54.

McKendry, P. 2002b. Energy production from biomass (part 3): Gasification technologies. Bioresource Technology 83(1): 55-63.

Milne, T.A., Abatzoglou, N. & Evans, R. 1998. Biomass Gasifier “tars”: Their Nature, Formation, and Conversion, Colorado (US). https://www.nrel.gov/docs/fy99osti/25357.pdf. Accessed on 4 March 2020.

Mishra, R.K. & Mohanty, K. 2018. Pyrolysis kinetics and thermal behavior of waste sawdust biomass using thermogravimetric analysis. Bioresource Technology 251: 63-74.

Molino, A., Chianese, S. & Musmarra, D. 2016. Biomass gasification technology: The state of the art overview. Journal of Energy Chemistry 25(1): 10-25.

Monir, M.U., Khatun, F., Abd Aziz, A. & Vo, D.V.N. 2020. Thermal treatment of tar generated during co-gasification of coconut shell and charcoal. Journal of Cleaner Production 256: 120305.

Müller-Langer, F. & Kaltschmitt, M. 2015. Biofuels from lignocellulosic biomass - a multi-criteria approach for comparing overall concepts. Biomass Conversion and Biorefinery 5: 43-61.

Nakamura, S., Siriwat, U., Yoshikawa, K. & Kitano, S. 2015. Development of tar removal technologies for biomass gasification using the by-products. Energy Procedia 75: 208-213.

Nakamura, S., Kitano, S. & Yoshikawa, K. 2016. Biomass gasification process with the tar removal technologies utilizing bio-oil scrubber and char bed. Applied Energy 170: 186-192.

Nanda, S., Mohammad, J., Reddy, S.N., Kozinski, J.A. & Dalai, A.K. 2014.  Pathways of lignocellulosic biomass conversion to renewable fuels. Biomass Conversion and Biorefinery 4(2): 157-191.

Nunalapati, D., Gupta, R., Moghtaderi, B. & Wall, T.F. 2007. Assessing slagging and fouling during biomass combustion: A thermodynamic approach allowing for alkali/ash reactions.  Fuel Processing Technology 88(11-12): 1044-1052.

Nunes, L.J.R., Matias, J.C.O. & Catalão, J.P.S. 2016. Biomass combustion systems: A review on the physical and chemical properties of the ashes. Renewable and Sustainable Energy Reviews 53: 235-242.

Office of Agricultural Economics. 2018. Agricultural Statistics of Thailand in 2018. Office of Agricultural Economics, Ministry of Agriculture and Cooperatives of Thailand. http://www.oae.go.th/assets/portals/1/ebookcategory/27_yearbook2561/. Accessed on 20 June 2019.

Paethanom, A., Nakahara, S., Kobayashi, M., Prawisudha, P. & Yoshikawa, K. 2012. Performance of tar removal by absorption and adsorption for biomass gasification. Fuel Processing Technology 104: 144-154.

Paethanom, A., Bartocci, P., Alessandro, B.D., Amico, M.D., Testarmata, F., Moriconi, N., Slopiecka, K., Yoshikawa, K. & Fantozzi, F. 2013. A low-cost pyrogas cleaning system for power generation: Scaling up from lab to pilot. Apply Energy 111: 1080-1088.

Palamanit, A., Khongphakdi, P., Tirawanichakul, Y. & Phusunti, N. 2019. Investigation of yields and qualities of pyrolysis products obtained from oil palm biomass using an agitated bed pyrolysis reactor. Biofuel Research Journal 24: 1065-1079.

Pereira, E.G., da Silva, J.N., de Oliveira, J.L. & Machado, C.S. 2012. Sustainable energy: A review of gasification technologies. Renewable and Sustainable Energy Reviews 16(7): 4753-4762.

Phuphuakrat, T., Namioka, T. & Yoshikawa, K. 2011. Absorptive removal of biomass tar using water and oily materials. Bioresource Technology 102(2): 543-549.

Plante, L., Sheehan, N.P., Bier, P., Murray, K., Quell, K., Ouellette, C. & Martinez, E. 2019. Bioenergy from biofuel residues and waste. Water Environment Federation 91(10): 1199-1204.

Plis, P. & Wilk, R.K. 2011. Theoretical and experimental investigation of biomass gasification process in a fixed bed gasifier. Energy 36(6): 3838-3845.

Rajendran, K., Drielak, E., Varma, V.S., Muthusamy, S. & Kumar, G. 2017. Updates on the pretreatment of lignocellulosic feedstocks for bioenergy production - A review. Biomass Conversion and Biorefinery 8(2): 471-483.

Rasmussen, N.B.K. & Aryal, N. 2020. Syngas production using straw pellet gasification in fluidized bed allothermal reactor under different temperature conditions. Fuel 263: 116706.

Rubber Authority of Thailand. 2018. Academic Information of Rubber in 2018. https://km.raot.co.th/book/read-product/230. Accessed on 20 June 2019.

Saad, M.J., Chia, C.H., Zakaria, S., Sajab, M.S., Misran, S., Rahman, M.H.A. & Chin, S.X.  2019. Physical and chemical properties of the rice straw activated carbon produced from carbonization and koh activation processes. Sains Malaysiana 48(2): 385-391.

Schuster, G.L., Loffler, G., Weigl, K. & Hofbauer, H. 2001. Biomass steam gasification - An extensive parametric modeling study. Bioresource Technology 77(1): 71-79.

Seggiani, M., Vitolo, S., Puccini, M. & Bellini, A. 2012. Co-gasification of sewage sludge in an updraft gasifier. Fuel 93: 486-491.

Shen, Y. & Yoshikawa, K. 2013. Recent progresses in catalytic tar elimination during biomass gasification or pyrolysis-a review. Renewable and Sustainable Energy Reviews 21: 371-392.

Shrivastava, P., Khongphakdi, P., Palamanit, A., Kumar, A. & Tekasakul, P. 2020. Investigation of physicochemical properties of oil palm biomass for evaluating potential of biofuels production via pyrolysis processes. Biomass Conversion and Biorefinery. https://doi.org/10.1007/s13399-019-00596-x.

Sikarwar, V.S., Zhao, M., Fennell, P.S., Shah, N. & Anthony, E.J. 2017. Progress in biofuel production from gasification. Progress in Energy and Combustion Science 61: 189-248.

Stevens, D.J. 2001. Hot gas conditioning: Recent progress with larger-scale biomass gasification systems. National Renewable Energy Laboratory. https://www.nrel.gov/docs/fy01osti/29952.pdf.

Susastriawan, A.A.P., Saptoadi, H. & Purnomo. 2017. Small-scale downdraft gasifiers for biomass gasification: A review. Renewable and Sustainable Energy Reviews 76: 989-1003.

Tanger, P., Field, J.L., Jahn, C.E., Defoort, M.W. & Leach, J.E. 2013. Biomass for thermochemical conversion: Targets and challenges. Frontiers in Plant Science 4: 1-20.

Tarnpradab, T., Unyaphan, S., Takahashi, F. & Yoshikawa, K. 2016. Tar removal capacity of waste cooking oil absorption and waste char adsorption for rice husk gasification. Biofuels 7(4): 401-412.

Thapa, S., Bhoi, P.R., Kumar, A. & Huhnke, R.L. 2017. Effects of syngas cooling and biomass filter medium on tar removal. Energies 10(3): 349.

Tursi, A. 2019. A review on biomass: Importance, chemistry, classification, and conversion. Biofuel Research Journal 6(2): 962-979.

Unyaphan, S., Tarnpradab, T., Takahashi, F. & Yoshikawa, K. 2017. An investigation of low cost and effective tar removal techniques by venturi scrubber producing syngas microbubbles and absorbent regeneration for biomass gasification. Energy Procedia 105: 406-412.

Valderrama Rios, M.L., González, A.M., Lora, E.E.S. & Almazán del Olmo, O.A. 2018. Reduction of tar generated during biomass gasification: A review. Biomass and Bioenergy 108: 345-370.

Vecchione, L., Cossio, F. & Longo, L. 2016. Comparison of different systems for tar removal for renewable energy derivation from biomass gasification. Contemporary Engineering Sciences 9(9): 413-423.

Watson, J., Zhang, Y., Si, B., Chen, W.T. & de Souza, R. 2018. Gasification of biowaste: A critical review and outlooks. Renewable and Sustainable Energy Reviews 83: 1-17.

Werther, J., Saenger, M., Hartge, E.U., Ogada, T. & Siagi, Z. 2000. Combustion of agricultural residues. Progress in Energy and Combustion Science 26(1): 1-27.

Widjaya, E.R., Chen, G., Bowtell, L. & Hills, C. 2018. Gasification of non-woody biomass: A literature review. Renewable and Sustainable Energy Reviews 89: 184-193.

Yao, X., Zhou, H., Xu, K., Xu, Q. & Li, L. 2020. Investigation on the fusion characterization and melting kinetics of ashes from co-firing of anthracite and pine sawdust. Renewable Energy 145: 835-846.

Yokoyama, S.Y., Ogi, T. & Nalampoon, A. 2000. Biomass energy potential in Thailand. Biomass and Bioenergy 18(5): 405-410.

Yu, L.Y., Wang, L.W. & Li, P.S. 2014. Study on prediction models of biomass ash softening temperature based on ash composition. Journal of the Energy Institute 87(3): 215-219.

Zhu, Y., Niu, Y., Tan, H. & Wang, X. 2014. Short review on the origin and countermeasure of biomass slagging in grate furnace. Frontiers in Energy Research: Bioenergy and Biofuel 2(7): 1-10.

*Pengarang untuk surat-menyurat; email: arkom.p@psu.ac.th