Experimental investigation of Carbon dioxide absorption in a packed bed tower

Abstract

The continuous and unabated emission of CO2 from various industrial sources is a worrying sign for the future of this planet as it leads to global warming and alarmingly changing the geo-political and meteorological scenario of the world and at a faster rate. There has been an extensive research going on across various laboratories around the globe to mitigate this problem. Absorption using amine solutions, ionic liquids; adsorption on porous structural frameworks like zeolites, metal organic frameworks; natural storage (or, sequestration) under the favorable geological formations (under earth’s crust, ocean floor); chemical conversion to useful products are a few of the many steps that have been taken to address the issue. Although, a few of them have overcome the technological challenges and satisfies the economic feasibility and already implemented across various industries but many of the processes are yet to come out of their infancy and still at the nascent stage (lab stage) of their development before being implemented. In this project, CO2 was removed from (CO2+air) mixture using aqueous NaOH solution as the solvent in a packed bed absorption column. The column was operated counter currently using raschig ring as the packing material being randomly packed inside the column. CO2 removal efficiency was found to satisfactory approximately varying between 50-80% under various operational conditions. The effect of solvent flow rate on removal percentage was found to be important. The height of a transfer unit (HTU) and number of transfer units (NTU) were also calculated. Finally, overall mass transfer coefficients were also calculated from the absorption data