The efficient use of GGBS in reducing global emissions

Ground granulated blast furnace slag (GGBS) is a co-product of the iron and steel industry obtained by water-cooling and grinding blast furnace slag. It is used as a supplementary cementitious material (SCM) in concrete due to its cementitious properties, which enhance the long-term strength and durability.
The technical benefits of including GGBS in concrete are now well understood and documented, but in recent years GGBS has also been a subject of discussion among concrete producers for its ability to partially replace Portland cement clinker (referred to as ‘clinker’ in this paper) and thus reduce the emissions of an individual concrete.

This briefing paper provides:
(1) An objective view of global GGBS availability, both present and future, through market and industry research.
(2) An appraisal of how global greenhouse gas (GHG) emissions can be affected by concrete mix designs.
(3) Recommendations towards the efficient use of GGBS, in reducing global GHG emissions.

The paper uses terminology from BS EN 197-1:2001, Cement – Composition, specifications and conformity criteria for common cements, and equivalent standards as far as possible.1