Numerical Computations to Produce Cokeable Coal Blends at The Ajaokuta Steel Plant, Nigeria

A.O. ADELEKE, P. ONUMANYI

DEPARTMENT OF MATERIALS SCIENCE AND ENGINEERING,OBAFEMI AWOLOWO UNIVERSITY, ILE-IFE, NIGERIA.
DEPARTMENT OF MATHEMATICS,UNIVERSITY OF JOS,JOS, NIGERIA.

DOI: 10.4236/jmmce.2007.62010                

Abstract

A mathematical model and its associated numerical search algorithm has been developed for routine coal blending to include local coals for cokemaking at the Nigerian blast furnace-based Ajaokuta Steel Plant. A typical binary blend proposed using the model includes 28.38% and 29.00% of the ash- laden Lafia and non-caking Okaba coals, respectively. The proposed blends satisfy basic chemical and mechanical strength requirements at the lowest cost per ton of coal. The blending calculations showed that only low ash, low sulphur, medium volatile and high vitrinite reflectance prime grade coals such as the UK Ogmore should be imported for blending with the ash-laden medium coking Lafia coal. When the proposed blends are successfully confirmed with bench and pilot scale carbonization tests, cokemaking at Ajaokuta will be conducted with substantial savings in foreign exchange.

Keywords

model, coal, blending, cokemaking, blast furnace

Conflicts of Interest

The authors declare no conflicts of interest.

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