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What Is Slag?

There are a number of different types of Slag that are available and the information within these web pages refers solely to Ferrous Slags which are a by-product of the iron and steel making industry.

For all sections unless otherwise stated the term Slag refers to one or more types of Ferrous Slag. In the UK, slags are produced at iron and steel making facilities in the North of England and Wales.

Slag and Sustainability

Through the use of slag in a variety of applications there are distinct environmental advantages. For every tonne of slag utilised, there is an equivalent amount of quarried rock that is being replaced in the market, helping to both preserve our environment and conserve our natural resources. Additionally, through the successful utilisation of slag products, the need for landfill is avoided. As the source of these slag materials tend to be close to local conurbations and therefore the market, there is also a potential saving in transport costs and associated emissions. 

Ground granulated blastfurnace slag is a leading material in the sustainability debate. For every tonne used instead of Portland cement there is a saving of 1.5 tonnes of natural material and only one fifteenth of the energy is used. There is a very large saving in carbon dioxide emissions.

Where Do Slag Aggregates Come From?

Click the links below to view the production processes.

How Is Slag Used?

The main uses of Slag are in construction, water treatment, agriculture, cementitious applications. Full details of the specific properties and applications for each of the types of slag can be found on the below covering: