Technology development for the reduction of NOx in flue gas from a burner-type vaporizer and its application

We developed a modified process of a submerged combustion vaporizer (SMV) to remove nitric oxides (NOx) efficiently from flue gas of the SMV at liquefied natural gas (LNG) terminals. For this, excess oxygen is injected into exhaust gas that contains NOx from SMV burner. Then, the mixed gas spreads into a hydrogen peroxide solution or water bath. We initially performed experiments of the modified system to estimate the effect of various process variables (temperature, excess O2 concentration, pH of water, residence time of flue gas in water tank, and H2O2 concentration) on NOx conversion, and developed a mathematical model of the system based on the experiment results. Lastly, we confirmed higher performance of the modified system and validated the feasibility for its field application.