Study on the Reliability of Coke Research Establishment Micum 40 Formula to Predict Coke Micum 40 Strength at The Ajaokuta Steel Plant, Nigeria

A.O. Adeleke, A.O. Olulana, A.B. Adahama, R.S Makan, S.A. Ibitoye

Dept of Materials Science and Engineering, Obafemi Awolowo University,Ile-Ife, Nigeria..
National Metallurgical Development Centre (NMDC), P.M.B. 2116,Jos, Nigeria.
National Metallurgical Development Centre (NMDC), P.M.B. 2116,Jos, Nigeria..

DOI: 10.4236/jmmce.2007.62011                

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

Conflicts of Interest

The authors declare no conflicts of interest.

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