Achieving carbon neutrality in the power and industrial sectors necessitates the deployment of deep-decarbonization technologies that can retrofit existing fossil fuel infrastructure while ensuring economic viability. Industrial-scale oxy-fuel combustion (OFC) stands out as a promising pathway, producing a high-concentration CO₂ flue gas that significantly reduces the energy and cost penalties associated with downstream carbon capture.

A new paper from the School of Energy and Environment at Shenyang Aerospace University in China provides a comprehensive techno-economic assessment of OFC systems, integrating advancements across core components (oxygen production technologies, combustion system engineering, and oxy-fuel combustion carbon capture).

The paper begins by assessing the evolution and performance of oxygen supply systems—from mature cryogenic air separation to emerging adsorption and membrane-based methods-evaluating their energy consumption, capital and operational costs, scalability, and integration economics for industrial-scale OFC applications.

It further examines the combustion performance and economic implications of varying oxygen concentrations, comparing OFC with conventional air combustion and alternative clean combustion technologies. A key focus is placed on retrofit economics for existing thermal power plants, analysing the trade-offs between increased capital expenditure and reduced carbon capture costs.

The analysis centres on CO₂ separation, identifying the two-stage flash compression and purification unit process as the techno-economically preferred route, alongside emerging direct desublimation options that gain competitiveness through LNG cold-energy recovery or pressurised OFC operation.

The paper offers a systematic techno-economic review for evaluating OFC’s potential contributions to carbon neutrality in the combustion sector.