ICOPE-15-C147 Simultaneous removal of SO_2 and NO_x using ammonia-based aqueous solution in a submerged circulative impinging stream reactor

Abstract

Experiments were carried out in a self-designed submerged circulative impinging stream reactor in a continuous model aiming at simultaneous desulfurization and denitrogenation. Important parameters were studied and intensively discussed. The experimental results indicated that liquid level was an important factor on the denitrogenation and desulfurization efficiency. The effect of gas flow rate on desulfurization efficiency was weak while the NO_x removal efficiency increased with the increasing gas flow rate. The additional urea had a negative performance on denitrogenation efficiency while the increasing urea concentration showed no obvious improvement on SO_2 removal. The composition of aqueous solution was found to be an important factor on denitrogenation efficiency, which was caused by the mixing effect between liquid and gas. The mixture alcohol amine solution, a kind of surfactant, decreased the surface tension which is benefit for the formation and stabilization of small bubbles. Thus the contact area between liquid and gas increased and the mass transfer ability was enhanced. At optimal operation condition, the average desulfurization and denitrogenation efficiency can be achieved to 57% and 99.8%, respectively. Accordingly, the absorption of nitrogen oxides in ammonia-based aqueous solution shows a promising prospect to control the emission of SO_2 and NO_x simultaneously.