Mineral Products Association Ltd (MPA), Hanson Cement, Building Research Establishment, Forterra Building Products
• Up to 60% reduction in CO2 emissions vs CEM I (the market leader) • New cements have been demonstrated for use in all concrete applications • UK standards to be updated to include the new cements
Construction, cement, concrete
Cements for UK concrete applications generally consist of two main components which are usually Portland cement (CEM I) with limited quantities of either fly ash*, GGBS** or limestone powder. The scientific literature has shown that cements can work better if more than two main components are used. In this project, cements with three main components were developed: CEM I-fly ash-limestone powder, and CEM I-ggbs-limestone powder. Not only can cements with more than two components work better in concrete, there is also the opportunity to improve energy efficiency and to reduce embodied carbon vs. single component (CEM I) and two component cements (CEM II and CEM III).
Of the 10 clays investigated in the project, two clays will be selected for pilot scale production using two heating processes: (1) rotary and (2) flash. Following this, low-carbon cements will be formulated and tested for conformity against current standards. The calcined clays will be sent to the University of Dundee for rigorous strength and durability testing in concrete, with the aim of establishing their suitability as general purpose cements in BS 8500.
Currently 79% of the UK cement market sales is CEM I, with a total market of 10 million tonnes per annum. Of the new cements trialled in the project - one has a CO2 profile 60% lower than CEM I. If fully deployed this would result in a reduction in direct emissions from cement production of over 4 million tonnes of CO2 every year. On completion of the testing, the cements will need adoption and deployment.
MPA recommendations have been put to the British Standards Institution to include these new cements in the UK concrete standard (BS 8500), to help designers, specifiers, contractors and the wider construction sector reduce emissions related to the use of concrete.
The project was funded through the IEEA programme which supports the development of innovative technologies that will help industry reduce energy consumption and cut carbon emissions. It focuses on innovations with large potential cross-sector energy and carbon reduction impact - either new technologies or established technologies applied to new sectors. Over £15 million in public and private funding has been committed to develop solutions through partnerships between technology developers and industrial companies willing to test technologies on-site. The programme is funded by the UK government (BEIS) and managed by the Carbon Trust, with support from Jacobs.