Near-Zero Emissions Oxy-Fuel Combustion

The increased carbon dioxide (CO2) level in the atmosphere is the dominant contributor to the phenomenon of climate change. Anthropogenic CO2 (i.e. CO2 produced as a result of human activities) originates from the combustion of fossil fuels in power generation, transportation, and industrial and other sources. Currently, fossil fuels supply the bulk of the world’s energy and this situation is anticipated to continue for at least the next few decades. In order to continue using fossil fuels in an efficient and environmentally sustainable way, near-zero emissions technologies are being developed for demonstration and large-scale commercial deployment.

There are 3 main approaches to reducing the CO2 emissions from fossil fuel energy conversion processes, namely:

  • increase the efficiency of energy conversion systems and move towards more efficient power plants and advanced power cycles;
  • fuel switching, through the use of low-carbon fossil fuels such as natural gas, or by resorting to renewable or nuclear technology;
  • carbon management through the development and deployment of clean coal and CO2 capture and storage technologies.

CO2 capture and storage technology combined with improved energy conversion efficiency is a possible near-term solution to reducing CO2 emissions from fossil-fuel power generation on a global scale. Currently, near-zero emissions fossil-fuel technology can be achieved through three main CO2 capture pathways: pre-combustion, post-combustion, and oxy-fuel combustion.

CO2 Capture Pathways

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CO2 Capture Pathways

Oxy-Fuel Combustion

The oxy-fuel combustion pathway is a process of burning fossil fuels with an oxygen-enriched gas mixture instead of air. This results in a flue gas that mainly comprises CO2 and H2O (water), as well as a small concentration of impurities such as argon and oxygen. In this way, the oxy-fuel combustion process provides an opportunity to capture CO2 by direct physical compression and cooling techniques (such as a low-temperature separation/distillation process).

Oxy-Fuel Combustion Process

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Oxy-Fuel Combustion Process

The advantages of oxy-fuel combustion are:

  • a highly concentrated stream of CO2, ready for capture and storage;
  • excellent opportunities for integrated emissions control through reduced flue gas flow;
  • combustor unit size/volume that may be reduced to one-fifth of that used in air-fired combustion.

The novel application of oxy-fuel combustion technology to fossil-fuel energy conversion systems represents an emerging opportunity for developing new concepts and designs, increasing the efficiency of the baseline combustion processes, and reducing their environmental footprints, including greenhouse gas emissions, through CO2 capture and storage.

The current research on oxy-fuel systems at CanmetENERGY has focused on the development of next generation oxy-fuel combustion technologies, oxy-fuel process and power plant modeling, and oxy-fuel gas turbine technologies with near-zero emissions. New research activities include experimental investigation of oxy-fuel combustion processes for opportunity fuels and development of integrated processes for both hydrogen and oxygen production. These research activities are supported by a strong research team and by our state-of-the-art pilot-scale Vertical Combustor Research Facility.

The CanmetENERGY’s Oxy-Fuel Combustion Program enables industrial clients and stakeholders to collaboratively develop and examine advanced process configurations and new equipment design principles for the existing and new generation of oxy-fuel combustion systems with CO2 capture. The outcomes of our research support industry initiatives in this area and will assist them in determining cost-effective approaches for pre-commercial demonstration and commercial deployment of these near-zero emissions combustion systems.