Wet Removal of Sulfur Dioxide and Nitrogen Oxides from Simulated Flue Gas by Ca(ClO)_2 Solution

摘要

To study the simultaneous removal of Sulfur Dioxide (SO_2) and Nitrogen Oxides (NO_x) from simulated flue gas by wet method, a bubbling device containing calcium hypochlo-rite (Ca(ClO)_2) solution was used in the experiments. In the first place, thermodynamic analysis was conducted to determine the depth of reaction process, and the reaction mechanism of desulfurization and denitration was proposed. After that, experimental results exhibited that SO_2 could be removed by Ca(ClO)_2 solution completely while the removal efficiency of NO_x was 41.2%. Moreover, on the basis of high SO_2 removal efficiency, the effects of various factors on the removal efficiency of NO_x, such as: the height of liquid layer, Ca(ClO)_2 concentration, reaction temperature, initial pH value, O_2 percent, SO_2 concentration, and additives were investigated, respectively. Finally, simultaneous removal of SO_2 and NO_x under the optimized conditions were investigated, SO_2 removal efficiency of 100% and NO_x removal efficiency of 85.9% were achieved. The analysis of reaction products indicated that the main anions in the liquid phase were SO_4~(2-) and NO_3~-.