No. 117: Separating and collecting carbon dioxide from coal-fired thermal power by physical absorption (February 25, 2012)

Technology

J-Power is currently separating and collecting carbon dioxide by chemical absorption that uses amine solution for ion binding. Chemical absorption cannot be free from a certain limit because the amount of carbon dioxide increases with the absorbed amount. Physical absorption applies a high pressure to carbon dioxide and dissolves it in a special alcohol solution. That is, physical absorption is better than chemical absorption if the process grows higher in temperature and pressure. The company is constructing a test plant for physical absorption that is scheduled to be open shortly. Because the test plant is conducting tests of chemical absorption, it is the first test plant in the world that has test facilities both for chemical absorption and physical absorption. It plans to accumulate data and knowledge of physical absorption until 2013.

J-Power is working on the substantial experiments to generate electricity by driving a turbine using flammable gas collected from coal. At the same time, it is conducting experiments on the shift reaction of gases to separate carbon dioxide and hydrogen for effective collection of higly-pure carbon dioxide. Physical absorption will supposedly become widespread because increasing generation efficiency inevitably makes the process higher both in temperature and pressure. At the same time, physical absorption allows for desulfuration simultaneously because the degree of solubility of hydrogen sulfide is high in the alcohol solution.