New solvents and processes for post-combustion CO2 capture
Since it is proven, that the greenhouse effect is caused by men, strong actions are taken to find solutions against global warming. Today, most scientists are confident that carbon dioxide mitigation by carbon capture and storage is the most feasible option to significantly reduce the level of carbon dioxide emissions. Additionally, a slower climate change reduces the impact of the greenhouse effect. One of the most promising technologies is the Post-Combustion method, the capturing of CO2 after combustion.
The advantages of this technology are the feasibility for retrofit of existing power plants and the near readiness for marketing. In most applications, CO2 is captured by absorption into a solvent and released by stripping with water vapour after changing the temperature. By condensing the water out of the flue gas, almost pure CO2 can be stored underground. At present the absorption of CO2 is the most cost intensive stage and hence significant scientific effort has been directed to find more effective technologies, especially in developing new solvents.
In the first part of the project the vapour-liquid equilibrium (VLE) curve of new solvents should be determined experimentally for different temperatures. The VLE curve specifies the ability to capture CO2 and is the basis for the design of every absorption/stripping column. Additionally, important physical or chemical properties of solvents for CO2 absorption, should be investigated. Together with a continuously working absorption/stripping demonstrations column, measurements at a real power plant will be taken for MEA as a reference solvent and different new solvents. With these experiments, it is possible to determine the behaviour of the solvents under real conditions and other effects like cross reactions or fouling can be detected.
In the second part CO2 absorption experiments in a continuously working spray tower with following desorption unit are planed. The investment and operating costs of spray towers are lower compared to structured packing columns. The necessary installation size for the full scale applications are already available and proved through SO2 absorption. As a result of the project, the application of ionic liquids for CO2 capture should be evaluated and the achievable removal efficiency in a spray tower should be determined.
Dr. Martin Pogoreutz
Austrian Energy & Environment AG & Co KG
Project or cooperation partner
- Montanuniversität Leoben
- proionic GmbH