Abstract:
In 2002 the commissioning of an ilmenite smelter on the North Coast
of South Africa was extended by three months due to the failure
and subsequent replacement of the magnesia-based refractory
lining. The lining failed due to the hydration of magnesia caused by
an unexpected source of water. The incident resulted in significant
financial losses and a prolonged insurance claim which was settled
in 2009. As magnesia-based refractories are used extensively in
both ferrous and non-ferrous applications, the authors of the paper
want to share the experience gained from this incident with others.
The paper reviews the literature available on furnace start-up
practices and explains the hydration of magnesia using available
sources. The incident is studied in more detail, both technically and
economically, and the costs incurred are quantified in terms of the
cost of the original lining. The paper concludes with lessons learned
and recommendations made for future work. The intention of the
paper is to stimulate open debate regarding best practices in
preheating of furnaces lined primarily with magnesia.
