Intensification of absorption rate of carbon dioxide and ammonia in a simulated packed (Stephens–Morris) column using pulsed gas phase under optimized parametric conditions

Abstract

BackgroundReducing gas emissions is a significant challenge in our ecosystem. Gas-liquid absorption is used in chemical industry to remove components from gas streams. Stephens–Morris tube, known for liquid-liquid and gas-liquid systems, has gained attention for gas absorption columns utilizing disc-shaped packing elements to improve mass transfer by creating tortuous flow path. MethodsThis investigation focuses on physical absorption of CO2 and NH3 in gas-liquid systems based on various process parameters vis. liquid flow rate (0.24–0.60 L/min), gas flow rate (6–60 L/min), pulsation frequency (0–9.06 Hz), pulsation amplitude (0–26 mm), effect of solute gas concentration (0–100 %), and effect of varying the number of discs in the disc column (15, 20, 25, 33). Response Surface Methodology (RSM) was used to predict maximum absorption efficiency under optimized conditions. Significant FindingsPulsation frequency and amplitude proportionally increased absorption coefficient, while liquid flow rate affected it differently in pulsed and unpulsed absorption. In gas film-controlled system, mass transfer coefficient was proportional to the gas flow rate. RSM yielded R2 of 0.975 while relative error and dwill was 0.097 and 0.96, respectively. Understanding system characteristics and operations at optimal pulsation frequencies and amplitudes can maximize absorption effectiveness, particularly for low-solubility gases dominated by liquid phase resistance.