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

Abstract

Reduction of nitrogen oxide (NO_x) 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, NO_x emission control mechanisms are divided into primary methods and after-treatment methods. After-treatment methods focus on reducing NO_x 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.

Keywords

• Marine SCR,Simulation,NOxReduction,Urea decomposition

Kaynakça

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