A by product from pig iron manufacture in the blast furnace is slag. Iron ore, coke and limestone are charged into the top of the blast furnace and a hot blast of air is blown into the furnace near the base. As the hot air burns the coke it reduces the iron ore to iron and the limestone, acting as a flux, promotes the formation of a slag which attracts and retains unwanted impurities. Until it became commercially viable to recover the slag (eg. in cement manufacture, road building etc.) the slag was dumped on a suitable site. In Workington, over a century of ironmaking has resulted in a huge man made hill which shelters the town from the sea. Whilst the former slag bank has largely been landscaped, the material is still being recovered and graded for resale as aggregate.

There is A process and apparatus by which blast-furnace slag can be added to the feedstock materials fed into the feed-end of a rotary cement kiln to form cement clinkers. The blast-furnace slag is crushed and screened to provide blast-furnace slag particles having particles with a predominant size of up to a maximum diameter of substantially 2" or less.

Blast Furnance Slag can be recycled into high quality cement clinkers, waterproofing material, raw ingredients for surface protection against chemical, abrasion, toxic, water, ...

Working on newest high technology recycling for blast furnance slag and fly ash.