The Blast Furnace Casthouse

An excellent casthouse operation is an important factor in a low cost, high productivity blast furnace operation. The casthouse functional design, operational practice, refractory technology, automatization and environmental requirements are described to meet today's demands for greater reliability and output. Danieli Corus' technologies, which have been successfully implemented into commercial practice, will be presented. The casthouse is the most labour intensive area in the entire blast furnace operation. Its design must be fully integrated with the expected hot metal production, hearth volume, and tapping practice whilst minimizing use of labour, maintenance, materials and improving working environment. The prime objective is to remove the liquid iron from the blast furnace at a casting rate and through a number of casts per day that is determined by the smelting rate, effective hearth volume, and the desire to maintain the hearth in a "dry" condition rather than by the availability of the casthouse troughs, runners and equipment.

Improving the working environment in the casthouse can be realised by a good casthouse layout, diligent "housekeeping", elimination of potential hazards, and containment of the dust and fumes emitted during casting operations. A substantial reduction in labour costs can be achieved through mechanisation and automation. A prerequisite of mechanisation is a level casthouse floor with flush and flat runner covers to provide mobile maintenance equipment with ease of access to all areas. Automation of all functions, such as dedusting damper position control, taphole drill and clay gun operation, via the software residing in a dedicated casthouse PLC in combination with radio controlled tapping equipment reduces labour requirements, allows operator mobility, and the convenience to effectively monitor each cast. The key to cost reduction in refractory consumption is to optimize the length, and extend the campaign life of the iron troughs and hot metal runner systems. These objectives can be attained by implementing forced air cooling along with temperature monitoring capabilities, primarily in the iron trough. The implementation of forced air cooling is particularly important where iron trough and/or hot metal runner covers are utilised.