Reclamation of ultra-fine coal with scenedesmus microalgae and comprehensive combustion property of the Coalgae® composite

Keywords: kinetics, modelling, optimisation, s-value, synergistic

Abstract

Combustion of South African discard ultra-fine coal (i.e. coal dust), charcoal, microalgae biomass, and composites of the three under air were studied. The study involves to find out the effect of Scenedesmus microalgae biomass on the comprehensive combustion characteristics of the ultra-fines. Coal dust is considered as waste material, but it could be modified and combusted for energy. The composites were designed with Design Expert, and unlike blending with the dry microalgae biomass, fresh slurry was blended with the ultra-fine coal and charcoal. Non-isothermal combustion was carried out at heating rate of 15 C/min from 40 – 900 ºC and at flow rate of 20 ml/min, O2/CO2 air. Combustion properties of composites were deduced from TG-DTGA and analysed using multiple regression. On combustion, the interaction of coal-charcoal-microalgae was antagonistic (b = - 1069.49), while coal-microalgae (b = 39.17), and coal-charcoal (b = 80.37), was synergistic (p = 0.0061). The coal-microalgae (Coalgae®) indicated first order reaction mechanism unlike, coal, and the charcoal. Comprehensive combustion characteristics index of Coalgae®, (S-value = 4.52E8) was superior relative to ultra-fine (S-value = 3.16E8), which indicated high quality fuel. This approach to combusting ultra-fine coal with microalgae biomass is partly renewable, and it would advance the production of heat and electricity.

Key words: coal-dust, combustion, s-value, Coalgae®, renewable.

References

Chamber of Mines of South Africa. 2018. National Coal Strategy. Available at: www.chamberofmines.org.za (Accessed: 4 February 2020).
Antal, M. J. 2003. The art, science, and technology of charcoal production, Industrial & Engineering Chemistry Research, 42: 1619–1640.
Arias B., Pevida C., Rubiera F. and Pis J.J. 2008. Effect of biomass blending on coal ignition and burnout during oxy-fuel combustion, Fuel, 87: 2753–2759. doi: http://dx.10.1016/j.fuel.2008.01.020.
Bakhtyar, B., Ibrahim Y., Alghoul MA., Aziz N., Fudholi A. and Sopian K. 2014. Estimating the CO2 abatement cost: substitute price of avoiding CO2 emission (SPAE) by renewable energy’s feed in tariff in selected countries, Renewable and Sustainable Energy Reviews 35: 205–210. doi: https://doi.org/10.1016/j.rser.2014.04.016.
Baxter, L. 2005. Biomass-coal co-combustion : opportunity for affordable renewable energy, Fuel, 84: 1295–1302. doi: https://doi.org/10.1016/j.fuel.2004.09.023.
Baxter, L. 2010. Green energy and technology. Edited by Panagiotis Grammelis. Springer London Dordrecht Heidelberg New York. doi: http//:doi.10.1007/978-1-84996-393-0.
Borowitzka, M. A. 1999. Commercial production of microalgae: ponds, tanks, tubes and fermenters, Journal of Biotechnology, 70: 313–321.
Bosma, J. 2012a. Bivariate regression for analysts, scientists and engineers, Port Elizabeth, South Africa.
Bosma, J. 2012b. Introduction to data analysis for analysts, scientists and engineers, Port Elizabeth, South Africa.
BP Energy. 2018. BP Statistical review of World Energy 2018.
Bunt, J. R., Neomagus J.P. and Botha A.A. 2015. Reactivity study of fine discard coal agglomerates, Journal of Analytical and Applied Pyrolysis, 113: 723–728. doi: http//:doi.10.1016/j.jaap.2015.03.001.
Burhenne, L., Messmer J., Aicher T. and Laborie M. 2013. The effect of the biomass components lignin, cellulose and hemicellulose on TGA and fixed bed pyrolysis, Journal of Analytical and Applied Pyrolysis, 101: 177–184. doi: https://doi.org/10.1016/j.jaap.2013.01.012.
Campus, T. 2019. South Africa’s mineral industry 2017/2018 -SAMI-. Pretoria. Available at: www.dmr.gov.za.
CarbonBrief. 2018. The carbon brief profile : South Africa, CarbonBrief’s country profile series. Available at: https://www.carbonbrief.org/the-carbon-brief-profile-south-africa (Accessed: 4 February 2020).
Chen, C. Zhao, X., Yen, H., Ho, S. and Cheng, C. 2013. Microalgae-based carbohydrates for biofuel production, Biochemical Engineering Journal, 78: 1–10. doi: https://doi.org/10.1016/j.bej.2013.03.006.
David, P. 1995. The south african coal mining industry: a need for a more efficient and collaborative supply chain, Journal of Transport and Supply Chain Management, 5(1(2011)).
Demirba, A. 2003. Sustainable cofiring of biomass with coal, Energy Conversion and Management, 44(9): 1465–1479. doi: https://doi.org/10.1016/S0196-8904(02)00144-9.
Department of Energy. 2018. 2018 South African energy sector report. Pretoria. Available at: www.energy.gov.za.
Filippis, P. D., Caprariis B.D., Scarsella M. and Verdone N. 2015. Double distribution activation energy model as suitable tool in explaining biomass and coal pyrolysis behavior, Energies, 8: 1730–1744. doi: https://doi.org/10.3390/en8031730 .
Gil, M. V., Casal D., Pevida C., Pis J.J. and Rubiera F. 2010. Thermal behaviour and kinetics of coal/biomass blends during co-combustion, Bioresource Technology, 101(14): 5601–5608. doi: http://dx.doi.org/10.1016/j.biortech.2010.02.008.
James, G. S. 2005. Handbook of coal analysis. John Willey & Sons Inc. New Jersey. 2005.
Joel, C. 2010. Combustion characteristics of biomass briquettes. University of Nottingham.
Jones, J. M. and Ross, A. B. 2017. Organic carbon emissions from the co-firing of coal and wood in a fixed bed combustor, Fuel, 195: 226–231. doi: https://doi.org/10.1016/j.fuel.2017.01.061.
Khawam, A. and Flanagan, D. R. 2006. Solid-state kinetic models : Basics and mathematical fundamentals: 110(35): 17315–17328. doi: https://doi.org/10.1021/jp062746a.
Lee, J., Kim D., Lee, J.P., Park, S.C., Koh J.H., Cho, H.S. and Kim, S.W. 2002. Effects of SO2 and NOx on growth of Chlorella sp. KR-1, Bioresource Technology, 82: 2–5.
Moon, C., Sung, Y., Ahn. S., Kim, T., Choi, G. and Kim, D. 2013. Effect of blending ratio on combustion performance in blends of biomass and coals of different ranks, Experimental Thermal and Fluid Science, 47: 232–240. doi: https://doi.org/10.1016/j.expthermflusci.2013.01.019.
Munzhedzi, R. and Sebitosi, A. B. 2009. Redrawing the solar map of South Africa for photovoltaic applications, Renewable Energy, 34: 165–169. doi: https://doi.org/10.1016/j.renene.2008.03.023.
Muzenda, E. 2014. Potential uses of South African coal fines, 3rd International Conference on Mechanical, Electronics and Mechatronics Engineering (ICMEME 2014): 37–39.
Niu, S., Han, K. and Lu, C. 2011. Characteristic of coal combustion in oxygen/carbon dioxide atmosphere and nitric oxide release during this process, Energy Conversion and Management, 52(1): 532–537. doi: https://doi.org/10.1016/j.enconman.2010.07.028.
P. Spolaore, C. Joannis-Cassan, E. and Duran, A. I. C. 2006. Commercial applications of microalgae, Journal of Bioscience and Bioengineering, 101: 201–211.
Packer, M. 2009. Algal capture of carbon dioxide; biomass generation as a tool for greenhouse gas mitigation with reference to New Zealand energy strategy and policy, Energy Policy, 37(9): 3428–3437. doi: https://doi.org/10.1016/j.enpol.2008.12.025.
Pirraglia, A., Gonzalez, R., Denig, J., Saloni, D. and Wright, J. 2012. Assessment of the most adequate pre-treatments and woody biomass sources intended for direct co-firing in the U.S., 7: 4817–4842.
Plis, A., Lasek, J. and Skawi, A. 2017. Kinetic analysis of the combustion process of Nannochloropsis gaditana microalgae based on thermogravimetric studies, Journal of Analytical and Applied Pyrolysis, 127(March):109–119. doi: https://doi.org/10.1016/j.jaap.2017.08.017.
Rafey, W. and Sovacool, B. K. 2011. Competing discourses of energy development : The implications of the Medupi coal-fired power plant in South Africa, Global Environmental Change, 21(3): 1141–1151. doi: https://doi.org/10.1016/j.gloenvcha.2011.05.005.
Rosemary, F. 2013. Coal geology, types, ranks and grades in coal, coke and carbon in the metallurgical industry.
Sami, M., Annamalai, K. and Wooldridge, M. 2001. Co-firing of coal and biomass fuel blends, Progess in Energy and Combustion Science, 27: 171–214.
Shen, D. K., Gu, S., Luo, K.H., Bridgwater. A.V. and Fang, M.X. 2009. Kinetic study on thermal decomposition of woods in oxidative environment, Fuel. Elsevier Ltd, 88(6): 1024–1030. doi: https://doi.org/10.1016/j.fuel.2008.10.034.
Spolaore, P., Joannis-cassan, C., Duran, E., Isambert, A., Génie, L.D. and Paris E.C. 2006. Commercial applications of microalgae, Journal of Bioscience and Bioengineering, 101(2): 87–96. doi: https://doi.org/10.1263/jbb.101.87.
Syed, S., Qudaih, R., Talab, I. and Janajreh, I. 2011. Kinetics of pyrolysis and combustion of oil shale sample from thermogravimetric data, Fuel, 90(4): 1631–1637. doi: https://doi.org/10.1016/j.fuel.2010.10.033.
Xiumin, J., Chuguang, Z., Jianrong, Q., Jubin, L. and Dechang, L. 2001a. Combustion characteristics of super fine pulverized coal particle: 1100–1102.
Xiumin, J., Chuguang, Z., Jianrong, Q., Jubin, L. and Dechang, L. 2001b. Combustion characteristics of super fine pulverized coal particles, Energy & Fuels, 15: 1100–1102.
Yun, Y., Lee, S.B., Park, J.M. and Lee, C.I., 1997. Carbon dioxide fixation by algal cultivation using wastewater nutrients.
Zeelie, B. 2013. Carbonaceous fines beneficiation using micro-algae and related processes. South Africa: US Patent.
Views
  • Abstract 129
  • pdf 140
Views and downloads are with effect from 11 January 2018
Published
2020-02-28