Cement 2 Zero

In 2018, 7.3Mt of CO2 emissions were attributable to the UK concrete and cement sector; 4.4Mt of which were from clinker production. Researchers at the UoC have invented a new process of clinker production which has the potential to eliminate these emissions and enable the production of zero emission cement. The vision of Cement 2 Zero (C2Z) is to demonstrate this innovative process on an industrial scale for the first time.

Described by Tarmac's Innovation Director as "an exciting option for future cement", Cambridge Electric Cement (CEC) is the world's first potentially zero emission cement, made by recycling used cement in a symbiotic process with steel recycling (Electric Arc Furnace - EAF). Existing methods of reducing cement emissions rely on supplementary materials, whilst these strategies reduce emissions, they cannot eliminate them entirely as a proportion of Portland Cement is still required. In contrast, the CEC process does not make a supplementary material, CEC can directly replace Portland Cement, enabling zero emission cement production.

Not only will this transform cement production, but it will also diversify and expand steel recycling, and reduce process emissions. If UK steel recycling expands to process the 11Mt of steel scrap collected annually in the UK, CEC production could meet 25% of UK cement demand. There are currently no other options available for producing any cement without emissions.

C2Z will investigate both the technical and commercial aspects of the process. This will involve Techno-Economic Assessment, Life Cycle Assessment, the construction of a prototype crusher for concrete disaggregation and installation of a novel slag cooling system. 20 tonnes of CEC will be produced in an EAF at CELSA, which will be evaluated and used in a demonstration UK construction project. C2Z unites research expertise from the Materials Processing Institute (the Institute), the UoC, and the complete supply chain including Tarmac, CELSA, Balfour Beatty, Atkins, Brewster Brothers (a fast-growing SME), and Day Aggregates.

Using the EAF to recycle cement to reduce waste, energy, and emissions is a novel cross-sector technology adaption and the process has been proven and patented by the UoC (patent application: 2110292.6). This innovative industrial demonstrator will enable a significant step-change in cement production, the most important, prevalent, and CO2 emitting construction material. The project enables co-production of two critical materials, steel and cement, via one near zero emissions process, transforming a by-product of steel recycling into a valuable material.