Carbon Capture

Carbon capture refers to the process of intercepting and collecting carbon dioxide (CO₂) emissions generated by industrial activities — including mining, mineral processing, and smelting operations — before they are released into the atmosphere, for subsequent transportation to storage sites or utilization in industrial processes. In the context of bauxite mining, alumina refining, iron ore processing and steelmaking, gold mining, and diamond recovery, carbon capture represents one of the most technically ambitious and potentially impactful climate mitigation strategies for deep decarbonization of emissions that are difficult to eliminate through fuel switching or efficiency improvements alone. The three primary technology pathways for carbon capture are: post-combustion capture, which removes CO₂ from flue gases after fuel combustion using chemical solvents (such as amine-based solutions), physical solvents, solid sorbents, or membrane separation; pre-combustion capture, which converts fossil fuels into hydrogen and CO₂ before combustion, then captures the CO₂; and oxyfuel combustion, in which fuels are burned in nearly pure oxygen, producing a concentrated CO₂ exhaust stream that is easier to capture. Iron and steel production — a major downstream consumer of iron ore — is a priority sector for carbon capture deployment, with several demonstration projects targeting the capture of CO₂ from blast furnace gases. Aluminum smelters present a more complex carbon capture challenge due to the distributed nature of fluoride-containing emissions. Carbon capture is energy-intensive, adding a "capture energy penalty" that reduces net efficiency, and remains expensive at the commercial scale. Combined with carbon storage (geological sequestration) or utilization (CCU), it forms the broader concept of carbon capture, utilization, and storage (CCUS).