Experimental Studies of Additives for Suppression of Ammonia Vaporization in the Ammonia based CO2 Capture Process

Abstract

Ammonia-based CO2 capture process is a one of the promising technologies for CO2 mitigation in the industrial and power sector. Even though the process has many advantages compared with amine based CO2 capture processes, such as low reaction heat, low corrosiveness, and low chemical cost, it has received lesser attention than the amine processes. One of the important reasons is ammonia slip caused by the intrinsic nature of its high volatility. Many studies have been conducted to reduce ammonia slip, but few studies have been considered property changes such as heat of reaction, overall mass transfer coefficient and transfer capacity, comprehensively. To reduce ammonia slip, in this study, three additives have been tested. The property changes with additives were examined regarding ammonia vaporization, heat of reaction, overall mass transfer coefficient, and transfer capacity. According to the results, additives were effect in reducing the ammonia vaporization without any significant change on CO2 adsorption properties. Under laboratory conditions the most effective additive was additive A based on higher CO2 loading capacity, and less influence on reaction heat and mass transfer coefficient. For more practical evaluation, comprehensive studies including physic-chemical property changes in field conditions should be regarded.