Absorption principle and techno-economic analysis of CO2 absorption technologies: A review

Abstract

Abstract Since the industrial revolution, human activities have led to massive CO2 emissions, and the greenhouse effect has intensified. Therefore, scientists have developed and explored various CO2 capture technologies, such as absorption, adsorption, membrane separation and cryogenic technology. Among them, the absorption technology has been the most widely used. This paper reviews and summarizes the CO2 absorption technologies in the past ten years, introduces the principles of the following six mainstream technologies for CO2 absorption: monoethanolamine (MEA), ionic liquid, calcium looping, microalgae, ammonia, and molten carbonate fuel cells. Through comparing absorption cost, energy consumption, absorptivity as well as the advantages and disadvantages, this paper reveals that calcium looping and ammonia are the relatively suitable technologies at present. The calcium looping has low capture cost and energy consumption, but the reaction capacity of CaO adsorbent decreases rapidly during the absorption process. The absorptivity of ammonia is high and fertilizers (NH4HCO3) with added value can be produced, but the ammonia volatilization problem is challenging. Consequently, the two technologies have their own advantages and disadvantages and should be used considering the actual situation. The conclusions of this paper can guide industries to select CO2 absorption technologies with relatively lower cost, less energy consumption and higher absorptivity.