Carbon Capture and Management Strategies for Decarbonizing Secondary Aluminium Production
Abstract
The production of aluminium relies heavily on fossil fuels, leading to significant greenhouse gas emissions. As the industry seeks to reduce its environmental impact, eliminating direct emissions from remelting is increasingly crucial. This research explores decarbonizing secondary aluminium remelting and rolling through optimized carbon capture and abatement strategies. Various capture and management routes are developed and evaluated using process integration and optimization techniques via mixed integer linear programming (MILP). A blueprint of an aluminium plant is designed, integrating multiple carbon capture and management technologies, including oxy-combustion, amine-based absorption, membranes, structured solid sorbents and cryogenic beds. Captured CO2 can be pressurized for pipeline transport and injection into basaltic rock formations, converted into synthetic natural gas, mineralized into cement additives or lower CO2 taxes via injection routes results in a net negative change in plant operating costs compared to continued fossil CO2 emissions. Methanation offers a potential defossilization route when renewable electricity is available but incurs higher CO2 upgrading costs than currently subsidized fossil fuel prices. Similarly, producing value-added chemicals (olefins) from captured CO2 remains costlier than current fossil-based commodity prices. Among the capture technologies, oxyfuel combustion proves particularly promising in secondary aluminium production due to its energy efficiency and high technology readiness levels, leading to lower application costs. All these capture and utilization systems are nearly three times cheaper than importing green hydrogen for aluminium furnaces. Lastly, where concentrated point-source emissions are available, direct air capture, is more energy- and cost-intensive, while tree planting remains uncertain and land-occupying.
Bio
Dareen Dardor is a PhD in Energy candidate at École Polytechnique Fédérale de Lausanne (EPFL) in the group of Industrial Process and Energy Systems Engineering. My goal is to make contributions to science and help in developing innovative solutions for a sustainable future. I completed a BSc and Meng in Chemical Engineering with high distinction from Qatar University and Texas A&M University, respectively. I have five years of experience as a research engineer developing fit-for-purpose solutions for the treatment and management of wastewater from the oil & gas industry (at ConocoPhillips Global Water Sustainability Center). My PhD Thesis topic is about Developing Carbon Neutral Solutions Towards a Net Zero Aluminium Industry and is in the context of the Net Zero Lab Valais Consortium, a collaboration between EPFL, HES-SO, Novelis, and Oiken.