Process for CO_2 Capture Using Ionic Liquid That Exhibits Phase Change

摘要

A novel process for capturing carbon dioxide from the flue gas of a coal-fired power plant has been shown to reduce parasitic power consumption substantially. The process employs an ionic liquid created at the University of Notre Dame that has a high capacity for absorbing CO_2 by chemical reaction. A distinguishing property of this ionic liquid is that it changes phase from solid to liquid upon reaction with CO_2. The process uses heat generated by this phase transition to lower parasitic power consumption. The driving force for CO_2 separation is a combination of temperature and pressure differences; the process could even work without the addition of heat A realistic process was created to capture CO_2 efficiently. Computer simulation of the process enabled calculation of viable process conditions and power usage. The main concepts of the process were shown to work using a lab-scale apparatus. Parasitic power consumes 23% of net power generation, 55% lower than that of the monoethanolamine (MEA) process. However, capital cost is higher. The cost of electricity (COE) is 28% lower than that of the MEA process.