Largest carbon dioxide separation technology for power generation developed in South Korea

Korea Institute of Energy Research (KIER) has successfully demonstrated the world’s largest gas power generation technology capable of inherently separating carbon dioxide. They have also become the first in the world to use this approach to successfully generate steam for electricity production.

In conventional gas power generation, fuel combustion releases carbon dioxide, a major greenhouse gas, along with nitrogen and water vapor. Once emitted, CO₂ mixes with nitrogen from the air, necessitating specialized facilities to selectively separate and capture pure CO₂ for storage. This additional process increases power generation costs.

To tackle this challenge, chemical looping combustion (CLC) technology is emerging as an eco-friendly power generation solution. Unlike conventional methods where fuel reacts directly with air, CLC technology delivers pure oxygen to the fuel using oxygen-carrying particles. These particles release oxygen during combustion and later reabsorb it when exposed to air, continuously repeating the cycle to sustain the process.

By leveraging this technology, fuel interacts exclusively with pure oxygen, eliminating any reaction with nitrogen from the air. As a result, the combustion process generates carbon dioxide and water vapor, therefore after condensation of water vapor, enabling direct capture without the need for additional separation. Additionally, unlike conventional combustion, which produces nitrogen oxides (NOₓ), a major contributor to ultrafine particulate matter, this technology operates through flameless combustion, drastically reducing NOₓ emissions.

The research team, in collaboration with KEPCO Research Institute, developed a world-class chemical looping combustion (CLC) technology. In 2023, they established a 3 MW-scale pilot plant, the largest of its kind globally, and conducted full-scale demonstration tests. Over 300 hours of continuous operation, the technology achieved a carbon dioxide separation and emission efficiency exceeding 96%, surpassing the previous global benchmark of 94%.

Along with the successful demonstration, the research team has also opened the door to commercialization. For the first time in the world, they have successfully produced steam for power generation using chemical looping combustion (CLC) technology. While advanced countries such as the European Union, China, and the United States have been conducting CLC technology demonstrations, none have yet achieved steam production.

If the demonstration scale of the technology is small, efficiency is high, but heat loss is significant, making it impossible to generate steam. Similarly, if efficiency cannot be maintained while scaling up, steam production does not occur.

However, the research team has enabled steam production by developing process design and operation technologies that minimize heat loss while scaling up and by advancing large-scale production techniques for oxygen carrier particles. This transition has moved the technology from the realm of promising future innovations to the domain of commercialization.

An economic analysis of chemical looping combustion (CLC) technology predicts that, compared to a conventional 100MW natural gas power plant, it will generate an annual operating profit of 14.4 billion KRW and improve power generation efficiency by 4%.

Notably, CO₂ capture costs are expected to be reduced by 30% compared to existing methods, enabling the capture of over 150,000 tons of CO₂ per year. This advancement is expected to make a significant contribution to achieving national carbon neutrality goals.

Dr. Ryu Ho-jung, the lead researcher of the CCS Research Department, stated, “To achieve national carbon neutrality, it is essential to establish and operate gas power plants that incorporate innovative technologies such as chemical looping combustion (CLC).

“We will continue to advance and demonstrate our technology to accelerate the commercialization of next-generation power generation solutions.”