Application of green hydrogen for decarbonization of cement manufacturing process: A technical review

Abstract

Abstract Rising carbon dioxide (CO2) levels in the atmosphere have a direct effect on the weather, climate events, and global temperature that leads to adverse impacts on the environment and human beings. Industrial sectors are the major source of carbon footprint and contribute more than 30% of global CO2 emissions in global cement industries being the second largest after the steel industry i.e., 7% contribution. Raw material preparation, clinker burning, and cement grinding are the three major processes involved in cement manufacturing. The CO2 emissions throughout these phases are split into two categories: direct emissions (90%), mostly from the burning of fossil fuels and the breakdown of limestone (CaCO3) during the calcination of raw materials; and indirect emissions (2–10%), primarily from the use of electricity. Fossil fuel combustion is the major source of energy in cement manufacturing processes, accounting for 35% of cement’s CO2 emissions. In this study, the various pathways of decarbonization of the cement industry have been extensively reviewed. This research has revealed that hydrogen may be an appropriate substitute for carbon-intensive fuels in kilns. It can be concluded that the usage of hydrogen as a source of process heat, can present a potential for comparatively smooth integration into, or replacement of, process heat systems based on fossil fuels.