Metallurgical Slags

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Metallurgical slags are co-products of the iron and steel industry. They are non-metallic materials which are produced together with the metallic products of these processes. Owing to
• careful selection
• suitable process route
• appropriate heat treatment
• good processing
a range of construction, agricultural and other products is formed for use in a large number of important applications.

Iron- and steel making are high tech, well-controlled process operations which employ the most up to date methods of manufacture. All metallurgical products have to meet stringent specifications and acceptance criteria, and as slag is produced under exactly the same regime they too are endowed with consistent compositional and performance characteristics. Metallurgical slags can be subdivided into blast furnace- and steel slags.

Slags are rock-like or glassy materials composed chiefly of lime and silica. Minor components are magnesia and alumina. The exact ratio of these constituents depends on the process origin of the slag. Post-furnace treatment is carried out to enhance and optimise the properties and qualities of such compositional characteristics to ensure that the requirements of the end user are completely matched.

The world-wide move towards environmental improvement inevitably means increasing the utilisation of slag in order to minimise the extractive quarrying of primary aggregates thereby protecting more of our natural resources and landscape.