CO2 Capture and Storage (CCS) from Flue Gas

As a measure against global warming, there is an increasing demand for the development of technology for the recovery of carbon dioxide (CO2), a greenhouse gas, from thermal power plant fuel gas, and such development is underway around the world, especially for coal-fired thermal power plants, which produce large amounts of CO2 emissions. This technology is called CCS (Carbon dioxide Capture and Storage). Energy is required to separate and recover CO2 and store it deep underground or in the ocean, but consuming too much energy makes this technology meaningless as a measure against global warming. Therefore, an important technical challenge is to reduce the energy needed to separate, recover, and store CO2. Chiyoda is developing CCS, as a clean coal technology (CCT).

CO2 separation/recovery methods are classified into the following three types:

  1. Chemical absorption method
  2. Physical absorption method
  3. Membrane separation method

Flue gas has low CO2 content and low pressure, and therefore, the chemical absorption method is considered suitable for separating and recovering CO2 from flue gas. Chiyoda is continuing efforts with a focus on the chemical absorption method, aiming to put a CO2 separation/recovery system that allows for improved energy efficiency in an entire plant to commercial use.
In addition, Chiyoda is participating in research studies for CO2 storage, as a shareholder in Japan CCS Co., Ltd.