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An integrated multidisciplinary approach
to furnace design that considers the interde
pendence between furnace cooling elements
and other furnace systems, such as binding,
cooling water, and instrumentation, is nec
essary to achieve maximum furnace produc
tion and a long refractory life. The retrofit of
the BHP Hartley electric furnace and the
Kidd Creek copper converting furnace are
successful examples ofan integrated approach
to furnace cooling design.
INTRODUCTION
The need for robust furnace cooling is driven by the need for smelter operators to intensify their operations (i.e., to maximize returns by minimizing vessel size and maximizing throughput). This is done by increasing the production rate of existing metallurgical furnaces without increasing their size or by adopting new processes that treat a large tonnage of material in a single vessel. Process intensification results in higher heat fluxes and, hence, accelerated refractory wear. However, the benefits of intense processes can be obtained while achieving long campaign life by implementing a robust furnace cooling system integrated with the furnace structural binding system, the refractory, and the control/monitoring system.1
A number of operations have found that their furnaces lack sufficient cooling and are inadequate to handle design production rates, experiencing severe refractory erosion and run-outs. As a result, cooling technology has been installed on a retrofit basis for many furnaces. Two examples of such retrofits, both completed by Hatch, are the BHP Hartley Platinum smelting furnace and the Kidd Creek converting furnace, which are discussed in the sidebar. The design improvements to these furnaces included one or more of the following:
* Water-cooled copper elements in the slag zone to stabilize refractory wear and increase furnace life.
* Air-cooled copper fins at the skew level to reduce matte/metal penetration into the brickwork.
* Water-cooled copper tapholes to prolong tapping channel campaigns.
* Instrumentation to monitor furnace and cooling system performance.
* Refractories.
* Binding systems to promote tight brick joints that are resistant to matte/metal or slag leaks.
FURNACE SIDEWALL COOLING A range of sidewall cooling technology is available for furnaces, depending on the intensity of the process. The types of cooling include:
* Force air-cooled copper fins attached to the shell plate in the metal/matte zone to maintain the temperature of the shell plate within acceptable limits and...