TITLE:
Numerical Computations to Produce Cokeable Coal Blends at The Ajaokuta Steel Plant, Nigeria
AUTHORS:
A.O. ADELEKE, P. ONUMANYI
KEYWORDS:
model, coal, blending, cokemaking, blast furnace
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.6 No.2,
October
20,
2007
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.