Life cycle assessment (LCA) of Egypt’s cement manufacturing processes employing alternative fuel

Abstract

The cement industry is one of the world's most significant industrial sectors for development, which can stimulate economic growth for many countries. In Egypt, rapid urbanization and industrialization increased the demand for building materials, thus increasing cement production capacity. This industry is complex, energy-intensive, and resource-consuming, using various raw materials and energy sources. That leads to releasing pollutants, causing severe environmental impacts affecting ecosystem and air quality, human health, and climate change. The industry is pressured to adopt new technologies to mitigate emissions and environmental impacts. This study aims to adopt a Life Cycle Assessment (LCA) approach in Egypt to evaluate the environmental impacts of cement manufacturing processes by substituting conventional fossil fuels with green hydrogen as an alternative fuel. The study presents a "cradle-to-gate" approach to the life cycle assessment of cement industry processes, classifying them into raw material transportation, processing and preparation, clinker creation, and cement production. Unlike LCA studies, the recent study involves assessing the environmental impacts of the cement raw material transportation process, switching conventional fuel used in transport trucks into green hydrogen. Thus, two Egyptian hypothetical cement plants were assumed: the first Egyptian Hypothetical plant (EHP1), which uses diesel in transport trucks, and the second Egyptian Hypothetical plant (EHP2), which depends on mainly green hydrogen fuel. On the other hand, three Egyptian hypothetical plants with different operation scenarios were proposed to evaluate the environmental impacts assessment of cement manufacturing processes in cement factories. These scenarios include EHP1 (recent/old scenario), which utilizes 100% of conventional fuels (coal and electricity) in all cement manufacturing processes; EHP2 (hybrid scenario), which operates 50% of g conventional fuels (coal) and 50% of alternative fuel (green hydrogen) in cement manufacturing processes, and EHP3 (sustainable scenario) which applies 100% of alternative fuel (green hydrogen) in all cement manufacturing processes. The study analyses were employed using Open LCA software version 1.11.0, applying two methods of LCIA IMPACT 2002+ (midpoint and endpoint). When comparing EHP1 and EHP2 of the cement raw material transportation process, the most favorable results of the lowest environmental impacts were achieved when green hydrogen fuel replaced the fossil fuels in EHP2. Additionally, for the cement manufacturing processes, the most significant results of the lowest environmental impacts, such as the global warming potential, aquatic acidification, nonrenewable energy, and terrestrial eutrophication, were achieved in EHP3 (sustainable scenario) when green hydrogen fuel replaced the fossil fuels in all cement manufacturing processes, following EHP2 (hybrid scenario) which contributed with lower environmental impacts than EHP1 (recent/old scenario) by substituting fossil fuel used in clinker creation process into green hydrogen alternative fuel. It was concluded that applying the LCA methodology allowed evaluation of the environmental impact and improvements obtained with the fuel substitution with a cleaner energy source. This approach is indispensable for evaluating the environmental benefits of applying new technologies to cement production, leading to sustainable industry development.