TITLE:
Study on the Reliability of Coke Research Establishment Micum 40 Formula to Predict Coke Micum 40 Strength at The Ajaokuta Steel Plant, Nigeria
AUTHORS:
A.O. Adeleke, A.O. Olulana, A.B. Adahama, R.S Makan, S.A. Ibitoye
KEYWORDS:
coal, blends, coking, micum, indices
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.6 No.2,
October
20,
2007
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.