Performance of a UV-assisted Hydrogen-peroxide-fed Spray Tower for Sulfur Dioxide Abatement

• Published in: Chemical engineering & technology 2013-07, Vol.36 (7), p.1255-1260
• Main Authors: Codolo, M., Bizzo, W., Bertazzoli, R.
• Format: Article
• Language: English
• Subjects: Hydrogen peroxide; Mass transfer; Spray tower; Sulfur dioxide
• ISSN: 0930-7516; 1521-4125
• DOI: 10.1002/ceat.201200699

Spray towers are widely used for controlling air pollution by gases such as SO2, CO2, NOx, and HCl. Results of sulfur dioxide absorption in a spray tower using solutions of 1 g L–1 and 2 g L–1 of hydrogen peroxide are reported. For comparison, a water and sodium hydroxide solution was also used for SO2 abatement. The results indicate that H2O2 may be an important alternative for SO2 removal in spray towers. A set of experimental removal efficiency data was obtained as a function of gas and liquid flow rates. Volumetric mass transfer coefficients (kga) were calculated and an experimental relationship among kga, gas, and liquid flow rates was proposed. As a final experiment, an oxidation process assisted by UV radiation using a 1 g L–1 solution of H2O2 was carried out to speed up the SO2 removal rate. The results obtained in this condition are similar to those achieved with a solution of 2 g L–1 H2O2. Results of SO2 absorption in a spray tower using hydrogen peroxide solutions are investigated. For comparison, a H2O and NaOH solution was also used. A correlation is proposed, which shows the strong influence of the liquid flow rate. The results indicate that H2O2 is an important alternative for SO2 removal in spray towers.