JMMCE  Vol.6 No.2 , October 2007
Study on the Reliability of Coke Research Establishment Micum 40 Formula to Predict Coke Micum 40 Strength at The Ajaokuta Steel Plant, Nigeria
Abstract: G-values of 0.97, 0.93, 0.94 and 1.01 were determined for Polish Bellview blend 1 (BV1), Polish Bellview blend 2 (BV2), Australian Agro-Allied blend (AA) and American Carbon Energy blend (CE), respectively. The coking duration of 18 hours, 17 hours, 16 hours and 22.5 hours, respectively were used to carbonize the coals each having volatiles 31.8%, 31.3%, 30.22%, and 21.90%, respectively. The Coke Research Establishment (CRE) formula predicted M40 micum strength of 77.98%, 77.12%, 77.55% and 92.05% for BV1, BV2, AA and CE blends, respectively. These predicted values were found to deviate from the experimentally determined M40 indices of 77.80%, 70.80%, 78.20% and 64.16% determined for BV1, BV2, AA and CE respectively by 0.18 units, 6.32 units, -0.65 units, and 27.89 units respectively. Thus, the best M40 index predicted was determined for BV1 blend with 0.97 G-value and 18 hours coking time with only a small allowable deviation of 0.18 units. The CRE formula has therefore been shown to be valid to predict M40 index of coke produced from coal blends with G-value of about 0.97 and carbonized at a moderate coking time of 18 hours. It has also been shown that the coking conditions that produce the best M40 index also produced the best M10 index.
Keywords: coal, blends, coking, micum, indices
Cite this paper: A. Adeleke, A. Olulana, A. Adahama, R. Makan and S. Ibitoye, "Study on the Reliability of Coke Research Establishment Micum 40 Formula to Predict Coke Micum 40 Strength at The Ajaokuta Steel Plant, Nigeria," Journal of Minerals and Materials Characterization and Engineering, Vol. 6 No. 2, 2007, pp. 135-142. doi: 10.4236/jmmce.2007.62011.

[1]   Krivandin, V. and Markov, B., 1980, Metallurgical Furnaces, 1st edn., Mir Publishers, Moscow.

[2]   Moitra, A.K., Banerjee, N.G., Shrinkhande, K.Y., Sing, K., Raja, K. and Banerjee, S., 1972, “Studies on coal carbonization in India”, Central Fuel Research Institute (FRI), Publication, pp. 17-23, 35-36.

[3]   Gibson, J., 1972, “Dilatometry and the Prediction of coke quality”. Yearbook of Coke Oven Managers, UK. pp. 182-201.

[4]   Afonja, A.A., 1991, New Techniques of low coking coal utilization in the blast furnace, In: The Seminar on the Potential of Nigeria Coals for Industries, Lagos.

[5]   Weskamp W., Rhode, W., Stewen, W., and Habermehl, T., 1987, “Greater coke strength through reactive additives to coking blends”, 1st International Cokemaking Congress, Essen, Section III.

[6]   National Metallurgical Development Centre (NMDC), Report of training at Deutsche Montane Technologies, Germany.

[7]   Prasad, H.N., Rao, P.V.T., Poddar, N.N. and Chaterjee, A., 1992, “Selection of coals for cokemaking by classical top charging and stamp charging”. 2nd international cokemaking congress, London, pp 231-235.

[8]   Garin, J., Pol, F. and Poulet, Ph., 1987, “Coal selection and blending practice at the USINOR Coke oven plant”. 1st International Cokemaking Congress, supplementary volume pp., Section III. 2.

[9]   Katsuhiko, O., Akira, K., Mitsumas, J., Seiji, N. And Kan, A., 1987, “Evaluation of coking Coal”, 1st International Cokemaking Congress, preprints Vol. 1, Essen, Section E.1.

[10]   Raw Materials specifications, 1994, for Federal Government Steel Companies, 1st edn., pp. 6.