Life Cycle Assessment of Sustainable Cement

Cement is the 'glue' in concrete, and provides the foundation on which modern civilisation is built. But this comes at a huge environmental cost - nearly half of all materials extracted from the Earth annually are used in concrete, and cement production alone accounts for 8% of human-caused CO2 emissions. By replacing traditional Portland cement with low-CO2, alkali-activated or alkaline earth-activated cement (AAC/AEAC), we can reduce these CO2 emissions by more than 80%. However, uptake of these low-carbon cements within industry has been slow, due to variability in characteristics of raw materials, and difficulty controlling the reaction, setting and hardening processes, which govern performance. The raw materials used are dictated by local availability, which results from local supply patterns, cost and transport logistics. The environmental and economic potential of these low-carbon cements depends heavily on cost, availability and suitability of the raw materials, and the needs of the end-user. Currently, understanding of the life cycle environmental and economic performance of these cements produced from commonly available raw materials is limited. This cross-disciplinary PhD project aims to develop a new material chemistry circularity comparative framework for sustainable cement for construction and energy sectors. It will perform a hybrid life cycle analysis (LCA) of AAC/AEAC produced from both traditional and non-traditional raw materials, in a system defined in space and time, and compare the environmental and economic performance of these low-carbon cements against traditional Portland cement. Using data of their material chemistry, mass, energy and transport sourced from industry partners, laboratory and the literature, the life cycle environmental impact and carbon cost of these low-carbon cements will be produced. It will model future scenario of AAC and hence forecast their impact towards Net Zero 2050 considering economy, geography, capacity, technology, energy and policy revolutions.