Experimental study on simulated denitrification of ship exhaust gas with NaClO2/Mg(OH)2 seawater solution

Abstract

In order to study the denitrification effect of NaClO2/Mg(OH)2 seawater solution, the wet oxidation denitrification experiment was carried out by circulating spray. The experiment compared the denitrification time of NaClO2 water solution, NaClO2 seawater solution and NaClO2/Mg(OH)2 seawater solution; at the same time, studied the influence of different NaClO2 concentration, spray solution temperature and NO concentration in flue gas on the denitrification effect of NaClO2/Mg(OH)2 seawater solution. The experimental results showed that during the cyclic spraying process, the NO removal rate of NaClO2 water solution, NaClO2 seawater solution, and NaClO2/Mg(OH)2 seawater solution could reach 100%, and the time to completely remove NO was 68, 85 and 91 minutes, respectively. The NaClO2/Mg(OH)2 seawater solution could keep the pH value above 8 under the action of Hydroxide ion and the acid-base buffering capacity of seawater. Under alkaline conditions, it effectively inhibited the decomposition of NaClO2 in the solution to produce ClO2 gas, and inhibiting the escape of ClO2 was the main reason for increasing the time for NaClO2 to remove NO. The removal rate of NO increased with the increase of the concentration of NaClO2 and the temperature of the spray solution, and decreased with the increase of the NO concentration in the flue gas; however, the denitrification time decreased with the increase of the temperature of the spray solution.