ABSTRACT
Despite the system is very effective in removing sulphur dioxide [“SO2”] and dark smoke, it has very little effect on nitrogen oxides [“NOx”] removal in the exhaust gas due to the poor solubility of NO in seawater while more than 90% of NOx is NO. Right now, the most commonly used technology for removing NOx in the exhaust gas is selective catalytic reduction [“SCR”] method using ammonia or urea to reduce the NOx to nitrogen. SCR has been successfully used in stationary sources and recently used in Euro V and higher vehicles. Its NOx removal efficiency varies from 50-90%. However, its application in marine engine is not common and its cost is very high that makes it difficult to be widely adopted by the trades.
