The Effect of Exhaust Temperature on Urea-Water Decomposition in Marine SCR Systems

Abstract

Reduction of nitrogen oxide (NOx) emissions from ships due to environmental pollution and greenhouse gas impact has been made obligatory by regulations introduced by the International Maritime Organization (IMO). Basically, NOx emission control mechanisms are divided into primary methods and aftertreatment methods. After-treatment methods focus on reducing NOx emissions from the exhaust gas by various methods. In this study, the efficiency of the urea transformation for different exhaust temperature values for a modelled Selective Catalytic Reduction (SCR) system has been investigated numerically. As a result of numerical model, isocyanic acid, temperature, urea and ammonia values have been determined for Urea-Water Solutions (UWS) process values. The study has been calculated by the computational fluid dynamics (CFD). The numerical results obtained were confirmed by experimental studies from the literature.