Solubility and Absorption Performance of Enhanced Amine Solvent (Stonvent) for Carbon Dioxide Removal

There has been increasing attention on developing technologies for carbon dioxide (CO2) capture and sequestration in order to reduce CO2 emissions into atmosphere while still allowing the use of fossil fuels. Hence, there is a need to efficiently remove the high CO2 content in bulk. This paper is a continuation of our previous preliminary work which observed that an enhanced amine solvent, Stonvent, had better CO2 solubility capacity compared to conventional amine. In this paper, the solubility of CO2 in Stonvent was further analyzed up to 70 barg using high pressure solubility cell. Then, CO2 absorption performance of Stonvent under continuous process was assessed at atmospheric pressure. The CO2 concentration in continuous absorption study was elevated from the usual 10 to 20% level done by other researchers to 40% in order to explore the possibility of capturing high CO2 concentration in methane gas stream. The continuous absorption experiment was conducted using Borosilicate glass column with diameter of 100mm and column height of 2.97m. The CO2 removal efficiency of Stonvent was benchmarked with 20 wt% monoethanolamine (MEA). It was observed that the CO2 loading in solubility cell increased almost linearly with increase of pressure while the absorption performance of Stonvent under continuous process at atmospheric pressure was slightly lower than MEA. The solubility finding shows that Stonvent has great potential for application to remove CO2 at high pressure.