Skip to main content
SpringerLink
Log in

Evaluation of beneficiation options for recovery of ultrafine thermal coal

  • Published:
Minerals & Metallurgical Processing Aims and scope Submit manuscript

Abstract

Recent requirements to reduce thermal coal plant emissions, and ultrafine coal’s tendency to produce these emissions due to its typically high ash and moisture contents have limited the use of ultrafine coal. Ultrafine coal in beneficiation plants are usually either disposed of in tailing ponds at a loss in combustible material or disposed of by blending with coarser higher-grade products, resulting in a reduction in marketed product quality. A study of the options for processing ultrafine coal, consisting of < 200 μm hydrocyclone overflow, with 38.8 percent ash content is presented here. Ultrafine coal was processed based on 200-μm sieve bend and 10-μm hydrocyclone classifications, enhanced gravity separation (EGS) and froth flotation concentration as well as combinations of these. Yield, combustible material recovery (CMR) and product humidity were evaluated as test results.

Depending on the processing applied, product ash content could be reduced up to 49.7 percent, and up to 95.8 percent CMR of the actual run of mill feed could be attained. All of the processing options analyzed could reduce produced thermal electric plant emissions due to ash and moisture from 22 to 38 percent of the actual unprocessed ultrafine coal product.

Froth flotation was found to be the optimal process, yielding a product with the lowest ash content attained of 19.5 percent and CMR of 92.3 percent. Being the most versatile of the processes evaluated, it is capable of producing coal with varied ash contents but is subject to potential variations in coal flotability. The most complicated of the processing options, a combined sieve bend recovery of the > 200 μm fraction and EGS processing of the 10 to 200 μm fraction was found to be the next best option, attaining a combined 90.1 percent CMR and 25.0 percent ash content.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Arbiter, N., 1985, “Flotation,” SME Mineral Processing Handbook, Weiss N.L., ed., Society for Mining, Metallurgy & Exploration, Englewood, CO, (5–1)–(5–110).

    Google Scholar 

  • Bosoaga, A., Panoiu, N., Mihaescu, L., Blackeedy, R.I., Ma, L., Pourkashanian, M., and Williams, A., 2006, “Pollutants from the combustion of solid biomass fuels,” Fuel, Vol. 85, 1591–1598.

    Article  Google Scholar 

  • Burt, R.O., and Mills, C., 1984, Gravity Concentration Technology, Elsevier, Amsterdam, 607 pp.

    Google Scholar 

  • Chugh, Y.P., Patil, D., Patwardhan, A., Honaker, R.Q., Parekh, B.K., Tao, D., and Latif Khan, 2000, “Development and Demonstration of Integrated Carbon Recovery Systems from Fine Coal Processing Waste,” U.S. National Technical Information Service, Springfield, VA, 163 pp.

  • Daniel, I., 2007, personal communication.

    Google Scholar 

  • Davis, V.L., Jr., Bethell, P.J., Stanley, F.L., and Lutrell, G.H., 1995, “Plant practices in fine coal column flotation,” High Efficiency Coal Preparation, S.K. Kawatra, ed., Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 237–246.

    Google Scholar 

  • European Commission, 2010, “Directive 2010/75/EU of the European Parliament and of the Council of 24,” November 2010, https://doi.org/eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:334:0017:0119:en:PDF, accessed Jan. 7, 2013, 103 pp.

    Google Scholar 

  • Fernandez, R.J., 2013, personal communication.

    Google Scholar 

  • Firth, B.A., 1999, “Australian coal flotation practices,” Advances in Flotation Technology, B.K. Parekh and J.D. Miller eds, Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 289–308.

    Google Scholar 

  • Fueyo, L., 1999, Equipos de trituración molienda y clasificación. Tecnología, diseño y aplicación, 2nd Edition, Rocas y Minerales, Madrid, Spain, 360 pp.

    Google Scholar 

  • Gagarin, S.G., Gyul’maliev, A.M., and Tolchenkin, Yu.A., 2008, “Trends in coal beneficiation: A review,” Coal, Vol. 51, No. 2, pp. 31–42, https://doi.org/10.3103/s1068364x08020014.

    Google Scholar 

  • Goktepe, F., Pooley, F.D., Williams, K.P., Wise, G.J., and Trillo-Soto, R., 1996, “Coal desulphurisation with the Mozley Multi-Gravity Separator,” Changing Scopes in Mineral Processing, M. Kemal, V. Arslan, A. Akar and M. Canbazoglu, eds., Balkema, Rotterdam, pp. 97–101.

    Google Scholar 

  • Gupta, A., and Yan, D., 2006, Mineral Processing Design and Operation. An Introduction, Elsevier Science & Technology, Amsterdam, 718 pp.

    Google Scholar 

  • Honaker, R.Q., 1998, “High capacity fine coal cleaning using an enhanced gravity concentrator,” Minerals Engineering, Vol. 11, No. 12, pp. 1191–1199, https://doi.org/10.1016/s0892-6875(98)00105-8.

    Article  Google Scholar 

  • Honaker, R.Q., and Das, A., 2004, “Ultrafine coal cleaning using a centrifugal fluidized-bed separator,” Coal Preparation, Vol. 24, pp. 1–18, https://doi.org/10.1080/07349340490467668.

    Article  Google Scholar 

  • Honaker, R.Q., Das, A., and Nombe, M., 2005, “Improving the separation efficiency of the Knelson Concentrator using air injection,” Coal Preparation, Vol. 25, No. 2, pp. 99–116, https://doi.org/10.1080/07349340590962757.

    Article  Google Scholar 

  • Honaker, R.Q., Mohanty, M.K., and Govindarajan, B., 1998, “Enhanced gravity separation: An effective tool for fine coal cleaning,” Proceedings of the 13th International Coal Preparation Conference, A.C. Partidge, and I.R. Partidge, eds., Australian Coal Preparation Society, Newcastle, Australia.

    Google Scholar 

  • Honaker, R.Q., and Ozsever, A.V., 2003, “Innovations in fine coal density separation,” Advances in Gravity Concentration, R.Q. Honaker, and W.R. Forrest, eds., Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 125–140.

    Google Scholar 

  • Honaker, R.Q., Patil, D.P., Sirkeci, A., and Patwardhan, A., 2001, “Production of premium fuels from coal refuse pond material,” Minerals & Metallurgical Processing, Vol. 18, No. 4, pp. 177–183.

    Google Scholar 

  • Honaker, R.Q., Paul, B.C., Wang, D., and Huang, M., 1995, “Application of centrifugal washing for fine-coal cleaning,” Minerals & Metallurgical Processing, Vol. 12, No. 2, pp. 80–84.

    Google Scholar 

  • Honaker, R.Q., Singh, N., and Govindarajan, B., 2000, “Application of dense medium in an enhanced gravity separator for fine coal cleaning,” Minerals Engineering, Vol. 13, No. 4, pp. 415–427, https://doi.org/10.1016/s0892-6875(00)00023-6.

    Article  Google Scholar 

  • Honaker, R.Q., and Wang, D., 1998, “Falcon Concentrators: A High Capacity Fine Coal Cleaning Technology,” SME Annual Conference & Expo, Orlando, FL, Preprint 98–212, Society for Mining, Metallurgy & Exploration, Englewood, CO, 9 pp.

    Google Scholar 

  • Honaker, R.Q., Wang, D., and Ho, K., 1996, “Application of the Falcon concentrator for fine coal cleaning,” Minerals Engineering, Vol. 9, No. 11, pp. 1143–1156, http://dx.doi.org/10.1016/0892-6875(96)00108-2.

    Article  Google Scholar 

  • Honaker, R.Q., Wang, D., and Voyles, R., 1996, “Evaluation of a Full-scale C40 Falcon Concentrator for Fine Coal Cleaning,” Coal Preparation ′96, Lexington KY, 7 pp.

    Google Scholar 

  • International Organization for Standardization, 2010, “ISO 1171:2010, Solid mineral fuels — Determination of Ash,” Geneva, Switzerland.

    Google Scholar 

  • Jameson, G.J., 1983, Proceedings, Improving Froth Flotation of Coal, W.B. Membrey, ed., ACIRL, University of New South Wales, New South Wales, Australia.

    Google Scholar 

  • Kawatra, S.K., and Eisele, T.C., 1987, “Column flotation of coal,” Fine Coal Processing, S.K. Mishra and R.R. Klimpel, eds., Noyes Publications, Park Ridge, NJ.

    Google Scholar 

  • Kawatra, S.K., and Eisele, T.C., 2001, Coal Desulfurization: High-Efficiency Preparation Methods, Taylor and Francis, New York.

    Google Scholar 

  • Kurose, R., Ikeda, M., and Makino, H., 2001, “Combustion characteristics of high ash coal in pulverized coal combustion,” Fuel, Vol. 80, pp. 1447–1455, https://doi.org/10.1016/s0016-2361(01)00020-5.

    Article  Google Scholar 

  • Laskowski, J.S., and Poling, G.W., eds., 1995, Processing of Hydrophobic Minerals and Fine Coal, Proceedings of the 1st UBC-McGill Bi-Annual International Symposium on Fundamentals of Mineral Processing, Montreal, Canada, Canadian Institute of Mining, Metallurgy and Petroleum.

    Google Scholar 

  • Luttrell, G.H., Honaker, R.Q., and Phillips, D.I., 1995, “Enhanced gravity separators: new alternatives for fine coal cleaning,” Proceedings of the 12th International Coal Preparation Conference, Center for Coal and Minerals Processing, Lexington, KY.

    Google Scholar 

  • Majumder, A.K., and Barnwal, J.P., 2006, “Modeling of enhanced gravity concentrators–present status,” Mineral Processing & Extractive Metallurgy Review, Vol. 27, pp. 61–86.

    Article  Google Scholar 

  • Majumder, A.K., and Barnwal, J.P., 2011, “Processing of coal fines in a wateronly cyclone,” Fuel, Vol. 90, No. 2, pp. 834–837, https://doi.org/10.1016/j.fuel.2010.10.038.

    Article  Google Scholar 

  • Majumder, A.K., Tiwaria, V., and Barnwala, J.P., 2007, “Separation characteristics of coal fines in a Knelson concentrator–A hydrodynamic approach,” Coal Preparation, Vol. 27, pp. 126–137, https://doi.org/10.1080/07349340701249745.

    Article  Google Scholar 

  • Meenan, G.F., 1999, “Modern coal flotation practices,” Advances in Flotation Technology, B.K. Parekh, and J.D. Miller, eds., Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 309–316.

    Google Scholar 

  • Menendez, M., Gent, M., Toraño, J., and Diego, I., 2007, “Optimization of multigravity separation for recovery of ultrafine coal,” Minerals & Metallurgical Processing. Vol. 24, No. 4, pp. 253–263.

    Google Scholar 

  • Öney, O., and Tanrıverdi, M., 2012, “Optimization and modelling of fine coal benefication by Knelson concentrator using central composite design (CCD),” Journal of Ore Dressing, Vol. 14, No. 27, pp. 11–18.

    Google Scholar 

  • Oruç, F., Özgen, S., and Sabah, E., 2010, “An enhanced-gravity method to recover ultra-fine coal from tailings: Falcon concentrator,” Fuel, Vol. 89, pp. 2433–2437, https://doi.org/10.1016/j.fuel.2010.04.009.

    Article  Google Scholar 

  • Osborne, D.G., 1988, Coal Preparation Technology, Graham and Trotman Ltd., London, 1175 pp.

    Google Scholar 

  • Patwardhan, A., Chugh, Y.P., Mohanty, M.K., and Sevim, H., 2003, “Comparative economics of advanced fine coal cleaning in refuse pond recovery and active mine applications”, Minerals & Metallurgical Processing, Vol. 20, No. 5, pp. 113–119.

    Google Scholar 

  • Rao, T.C. and Bandopadhyay, P., 1992, “Application of a Mozley mineral separator for treatment of coal washery rejects,” International Journal of Mineral Processing, Vol. 36, 137–150, https://doi.org/10.1016/0301-7516(92)90070-d.

    Article  Google Scholar 

  • Rao, T.C., Govindarajan, B., and Barnwal, J.P., 1995, “A simple model for industrial coal flotation operation,” High-Efficiency Coal Preparation, S.K. Kawatra, ed., Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 177–185.

    Google Scholar 

  • Rázumov, K.A., and Perov, V.A., 1985, Proyectos de fábricas de preparación de minerales, Mir, Moscow, Russia.

    Google Scholar 

  • Richard Mozley Ltd., 1992, “Operating Manual, Multi-Gravity Separator, Laboratory/Pilot Plant (with Speed Controller),” Issue 5, Redruth, Cornwall, U.K., 19 pp.

    Google Scholar 

  • Riley, D.M., Firth, B.A., and Lockhart, N.C., 1995, “Enhanced gravity separation, high efficiency coal preparation,” High Efficiency Coal Preparation: An International Symposium, S.K. Kawatra, ed., Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 79–88.

    Google Scholar 

  • Rubiera, F., Hall, S.T., and Shah, C.L., 1997, “Sulfur removal by fine coal cleaning processes,” Fuel, 76, 13, 1187–1194, https://doi.org/10.1016/s0016-2361(97)00015-x.

    Article  Google Scholar 

  • Talmage, W.P., and Fitch, E.B., 1955, “Determining thickener unit areas,” Industrial and Engineering Chemistry, Vol. 47, pp. 38–41, https://doi.org/10.1021/ie50541a022.

    Article  Google Scholar 

  • U.S. Environmental Protection Agency, 2015, “Clean Power Plan,” https://doi.org/www2.epa.gov/cleanpowerplan/clean-power-plan-existing-power-plants, accessed Sept. 3, 2015.

    Google Scholar 

  • Venkatraman, P., Luttrell, G.H., Yoon, R.H., Knoll, F.S., Kow, W.S., and Mankosa, M.J., 1995, “Fine coal cleaning using the multi-gravity separator,” High Efficiency Coal Preparation: An International Symposium, S.K. Kawatra, ed., Society for Mining, Metallurgy & Exploration, Englewood, CO, pp. 109–117.

    Google Scholar 

  • Wei, S.U., 2015, “Enhanced Actions on Climate Change,” https://doi.org/www4.unfccc.int/submissions/INDC/Published percent20Documents/China/1/China’spercent20INDC percent20-percent20on percent2030 percent20June percent202015.pdf, accessed Sept. 3, 2015.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. School of Mining, Energy and Materials Engineering, Universidad de Oviedo, Oviedo, Spain

    M. Menéndez (Professor), M. R. Gent (professor), P. Riesgo (professor) & A. Suarez (professor)

Authors
  1. M. Menéndez
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. M. R. Gent
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. P. Riesgo
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. A. Suarez
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to M. R. Gent.

Additional information

Paper number MMP-15-092.

Discussion of this peer-reviewed and approved paper is invited and must be submitted to SME Publications Dept. prior to Feb. 28, 2017.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Menéndez, M., Gent, M.R., Riesgo, P. et al. Evaluation of beneficiation options for recovery of ultrafine thermal coal. Mining, Metallurgy & Exploration 33, 116–125 (2016). https://doi.org/10.19150/mmp.6747

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.19150/mmp.6747

Key words

Search

Navigation