Capture of CO2 from coal-fired power plant with NaOH solution in a continuous

A continuous pilot-scale bubble-column scrubber with NaOH as the absorbent was used to explore the capture of CO2 gas from a coal-fired power plant. The experimental design was based on the results of previous study. The diameter of the column was 20 cm and the height of the column was 2.4 m. According to the S/N ratio, parameters, including absorption rate (R-A), absorption efficiency (E), overall mass-transfer coefficient (K(G)a) and ratio of the gas-liquid flow rate (R), were selected for Taguchi analysis to obtain optimum conditions. A total of eleven experiments were carried out to verify the optimum conditions here. The range of the gas-flow rate (Q(g)) and liquid-flow rate (Q(LT)) conducted in this work were 48-192 L/min and 1.6-10 L/min, respectively. The input gas concentrations were 9-12.2%. Using a steady-state material balance with a two-film model, R-A and K(G)a could be determined. The results showed that E, R-A and K(G)a were in the range of 30-98%, 1.03x10-(4).11.48x10(-4) molls-L and 0.018-0.058 1/s, respectively. The obtained scrubbing factors (phi) were 0.00285-0.146 mol/mol-L, while R was in the range of 0.23-24.14. The dynamic behavior of the scrubber was also discussed in this study. The results could be used as a basis for commercial scale operation for the carbon capture at a power plant as well as microalgae cultivation.