Proximate analysis, rheological properties and technological applications of some Nigerian coals
Tóm tắt
Nigeria is endowed with large coal deposits, but some of them are yet to be explored. A combination of proximate analysis and rheological properties were used in characterizing the newly discovered Tai, Garin Maiganga and Shankodi-Jangwa coals in order to determine their suitable applications. Tai, Garin Maiganga and Shankodi-Jangwa coals were found to have moisture contents of 9.61%, 5.51% and 1.33%; volatile matter contents of 45.11%, 40.53% and 17.37%; ash contents of 23.40%, 20.42% and 17.37%; and fixed carbon contents of 24.11%, 34.75% and 57.57%, respectively. Shankodi-Jangwa coal had the highest percentage of sulphur (1.63%), while both Tai and Garin Maiganga coals had sulphur contents of less than 1%. The agglomerating and rheological properties of the coals revealed that only Shankodi-Jangwa coal has some coking properties with a crucible number of 3.0, temperature range of 107°C, maximum fluidity of 300 and dilatometric G value of 0.96, indicating that it is a low-plasticity and medium-coking coal, which may be blended with strongly coking, low-ash, low-sulphur and high-fluidity coal. The results indicate that all the coal samples could be suitable for liquefaction; Shankodi-Jangwa coal may be suitable for hydro-gasification in the production of methane. Classification of the Tai, Garin Maiganga and Shankodi-Jangwa coals using the International Standard Organization (ISO) chart revealed that the ISO code numbers are 900, 800 and 622, respectively.
Tài liệu tham khảo
Oshinowo T, Ofi O: Chemical desulphurization of Lafia-Obi coal in aqueous ferric chloride. J Niger Soc Chem Eng 1984,3(1):148–150.
Famuboni AD: Maximizing exploration of Nigeria’s coal reserves. Steel Raw Materials Exploration Agency, Kaduna; 1988.
Jefford G, Cassey OP, de Swardt AMJ: The coal resources of Nigeria. Bulletin No. 28. Federal Government of Nigeria, Lagos; 1963.
Nwadinigwe CA, Egereonu UU: Chemical and instrumental analysis of Enugu coal. Niger J Min Geol 1985, 22: 149–151.
Jauro A, Agho MO, Abayeh OJ, Obaje NG, Abubakar MB: Petrographic studies and coking properties of Lamza, Chikila and Lafia-Obi of the Benue Trough. J Min Geol 2008, 44: 11–18.
Aderonpe WIA: Desulphurization of Nigerian Lafia-Obi coal for metallurgical coke production. PhD thesis. University of Ibadan; 1988.
Afonja AA: A study of potential of Nigerian coals for metallurgical coking. Paper presented at the 1st National Conference on Steel, Ovwian-Aladja, April 1983. 1983, 51–95.
Afonja AA: Optimization of the utilization of sub-bituminous coal in conventional and form coking. Int J Fuel Process Technol 1998, 7: 293–310.
Jauro A, Chukwu CJ: Production of formed coal from Nigerian coals. J Petrol Coal 2011, 53: 1–4.
American Society for Testing and Material (ASTM): Annual book of ASTM standard: petroleum products, lubricants and fossil fuels. ASTM, Easton; 1992.
Francis W, Peters MC (Eds): Fuels and fuels technology. Pergamon, New York; 1980.
Jauro A: Organic geochemistry of Benue trough coals: biomarkers, hydrocarbon generation and coking potentials. LAP Lambert Academic Publishing, Saarbrucken; 2011.
Obaje NG: Petrographic evaluation of the coking potentials of the Cretaceous Lafia-Obi coal deposits in the Benue trough of Nigeria. J Min Geol 1997, 43: 103–176.
Bustin RM, Cameron AR, Greve DA, Kalkreuth WD: Coal petrology: its principles, methods and applications (short course notes). Geological Association of Canada, St. John's; 1985.
Adeleke AA, Onumanyi P, Ibitoye SA: Mathematical optimization of non-coking coal inclusion in coking blend formulations. J Petrol Coal 2011, 53: 212–217.
Diez MA, Alvarez R, Barriocanal C: Coal for metallurgical coke production: predictions of coke quality and future requirements for coke making. Int J Coal Geol 2002, 50: 389–412. 10.1016/S0166-5162(02)00123-4
Mason DM, Gandhi K: Formulas for calculating the heating value of coal and coal char: development, tests and uses. Am Chem Soc Div of Fuel Chem 1980, 25: 235–245.
Williams K: Primary coal - analytical needs. J Pure Appl Chem 1977, 49: 1465–1473. 10.1351/pac197749101465
Nasirudeen MB, Jauro A: Quality of some Nigerian coals as blending stock in metallurgical coke production. J Miner Mater Char Eng 2011, 10: 101–109.
Adeleke AO, Olulana AO, Adahama AB, Makan RS, Ibitoye SA: A prediction of micum strength of metallurgical coke using Ruhr dilatometric parameters of parent coals. J Petrol Coal 2009, 51: 75–79.
Ahindra G, Amit C: Theory and practice of iron and steel making. Prentice-Hall, New Delhi; 2008.
Walker R, Mastalerz M, Padgett P: Quality of selected coal seams from Indiana: implications for carbonization. Int J Coal Geol 2001, 47: 277–288. 10.1016/S0166-5162(01)00046-5
James GS: The chemistry and technology of coal. 3rd edition. CRC/Taylor & Francis, Boca Raton; 2012.