Producing cement, essential for construction, accounts for approximately 7% of global carbon dioxide (CO2) emissions due to the high heat required, traditionally generated by burning fossil fuels. The HARMONI project, funded by the European Union with nearly €8 million, aims to replace fossil fuels with a blend of ammonia and hydrogen in cement plants.
The project will also investigate if this switch can help balance the electricity grid. Imperial College London researchers, from the Department of Civil and Environmental Engineering, will assess the environmental, economic, and social benefits of this new approach. High-temperature heat, crucial for industries like cement, steel, and glass, typically consumes 70%-92% of energy use.
Green ammonia, a carbon-free fuel produced using renewable energy, is a promising alternative. While it is easy to store and transport, it can be difficult to burn and may release harmful nitrogen oxides (NOx). HARMONI proposes recovering ammonia from wastewater, supplementing it with green ammonia, and splitting some into hydrogen on-site to improve combustion and achieve the necessary high temperatures for cement making.
Professor Evina Katsou, Chair in Water Engineering at Imperial College London, stated, “In HARMONI, our job is to check, across the whole life cycle, whether this approach really cuts emissions without creating new problems, using trialled scientific methods and data-driven evidence.” The system will also adapt its fuel mix to fluctuations in renewable power supply, enabling cement plants to act as 'intelligent energy hubs'.
The project partners will initially test technologies separately before integrating them into a digital twin of a real cement plant in Alicante, Spain. Professor Katsou, along with Dr Elham Mousania, Dr Daniel Dias, and Dr Elena Koumaki, will develop life cycle assessment models to track energy and water usage from raw materials to the factory gate. They will also collaborate with project coordinator SINTEF to estimate costs, examine social impacts like worker safety and job creation, and provide policy recommendations.
Dr Mousania highlighted the development of an interactive tool for other cement plants to explore the approach. The team is also designing a training programme with plant managers and staff, available online through the Erasmus+ Skills4EII Hub. The project, coordinated by SINTEF, aims to provide confidence to industry and policymakers by August 2029 on the viability of switching cement production to ammonia and hydrogen, with potential benefits for other heavy industries.
