Experimental Research On NO_x Removal From Marine Diesel Engine Exhaust Gas Based On Chlorate Oxidation

With the development of economic globalization, the amount of international shipping vessels that are linked to the global trade is increasing dramatically, and the air pollution problem is increasingly prominent accordingly, which has already affected health seriously of people. In recent years, with the increasingly stringent environment regulations on the emission of marine diesel engine exhaust gas, the treatment of exhaust gas has become an import and urgent task at present.In this paper, the mainstream denitrification technologies at home and abroad are introduced, and the advantages and disadvantages of which are summarized. Aiming at the problem about denitration of international shipping vessels exhaust gas. The method that removing NOx from marine diesel engine exhaust gas based on chlorate oxidation are proposed and the corresponding experiments are carried out in this paper. Based on the self-designed vessel exhaust gas simulative experiment table and the bubble reaction equipment, to research the denitrification performance of NaCIO solution the concentration of NO and O2 of the simulative exhaust gas, initial concentration and pH of absorption liquid are changed; to research the denitrification performance of NaClO2 solution the concentration of NO, SO2 and O2 of the simulative exhaust gas, initial concentration and pH of absorption liquid and the reaction temperature are changed.The experiment result shows that the denitrification efficiency of NaClO2 is obviously higher than NaCIO in the same condition, and the maximum NO rate of removal is 43.9% for NaCIO and 96% for NaClO2 under laboratory condition. It is obtained through experiments that reaction condition of high denitrification efficiency for NaCIO is that the initial concentration of NaClO solution is 0.01mol/L, the initial pH of absorption liquid is between 5-6 and the concentration of NO is 600ppm. The reaction condition of high denitrification efficiency for NaClO2 is that the initial concentration of NaClO2 solution is 0.01mol/L, the initial pH of absorption liquid is 6, the concentration of NO is 400 ppm and the reaction temperature is 50℃. The parallel experiment is carried out for NaC102 absorption solution under the above experiment condition, the average oxidation rate of NO can reach 87.6% and the average removal rate of NOX reaches 74%, which verifies the efficiency and stability of denitrification. From the experiment result, the denitrification efficiency of NaCIO are influenced greatly by the initial pH and concentration of absorption.the denitrification efficiency of NaClO2 are influenced greatly by the initial pH and concentration of absorption and the NO concentration of inlet exhaust gas.This paper researches the denitrification performance of NaClO and NaClO2 solution, which provides theory and experiment basis for the application in the real vessel.