Application of Taguchi Method in the Investigation of the Carbon Dioxide Removal Process Using Water Absorption Innovated with the Water-Film-Forming-Unit

摘要

The assessment of using water as the absorbent to capture CO_2 from simulated gas in a water scrubber coupled with the water-film-forming-unit was presented in this study. The water-film-forming-unit was used to enhance the contact area between liquid and gas phase by forming a huge number of water-films and fine-bubbles, which then, improve the CO_2 dissolving rate in water. The Taguchi statistical method was applied to assess the effects and the contributions of four factors including gas pressure, initial CO_2 concentration, gas-to-liquid ratio and temperature on the removal and absorption rates thoroughly and systematically. Based on the analysis data obtained by Taguchi method, the highest CO_2 removal percentage of nearly 90.0% is reached at the conditions of a low temperature of 10℃, a liquid-to-gas ratio of 1.40, a gas pressure of 0.30 MPa, and a high inlet CO_2 concentration. Meanwhile, when the pressure is 0.70 MPa, inlet CO_2 concentration is 35%, liquid-to-gas ratio is 0.70 and temperature is 10℃, the highest absorption rate is 44.5 × 104 mol s~(-1)L~(-1). These results may provide the evidence to apply this water absorption method for large-scale CO2 capture from exhaust gases and become a promising solution for the air pollution problem.