Inner Selective Non-Catalytic Reduction Strategy for Nitrogen Oxides Abatement: Investigation of Ammonia Aqueous Solution Direct Injection with an SI Engine Model

• Published in: Energies (Basel) 2019, Vol.12 (14), p.2742
• Main Authors: He, Fengshuo, Yu, Xiumin, Du, Yaodong, Shang, Zhen, Guo, Zezhou, Li, Guanting, Li, Decheng
• Format: Article
• Language: English
• Subjects: Ammonia; aqueous solution of ammonia; Aqueous solutions; Automobiles; Automotive parts; Boundary conditions; Carbon monoxide; Catalysts; Catalytic converters; Chemical reactions; Chemical reduction; combined injection; Computational fluid dynamics; Computer applications; Computer simulation; Cylinders; deNOx technology; Diesel engines; Diesel fuels; Emission control equipment; Emission standards; Emissions; Energy; Engine cylinders; Engines; Equivalence ratio; Exhaust systems; Gasoline; Gasoline engines; Heat; Hydrocarbons; Hydrogen; Industrial plant emissions; Injection; inner selective non-catalytic reduction; Internal combustion engines; Nitrogen oxides; Oxidation; Oxides; Peak pressure; Phase matching; Photochemicals; Pollutants; Purification; Selective catalytic reduction; Soot; Technology; Temperature; Water flooding; Working conditions
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en12142742

This study contributes to a method based on an aqueous solution of ammonia direct injection for NOx emissions control from internal combustion engines. Many previously published studies about deNOx technology are based on selective catalytic reduction (SCR), but only few deal with inner selective non-catalytic reduction (inner SNCR) technology, which is an intensive improvement of selective non-catalytic reduction (SNCR) applied in the in-cylinder purification procedure. Before numerical calculations were carried out, the computational fluid dynamic (CFD) simulation model was validated with steady-state experimental results. The main results revealed that with the increasing concentration of aqueous solution of ammonia, nitrogen oxides gradually decrease, and the largest decline of NOx is 65.1% with little loss of cylinder peak pressure. Unburned hydrocarbon (UHC) and carbon monoxide (CO) may increase using inner SNCR, and soot emissions show a decreased tendency. However, there is little change when ammonia content varies. Ulteriorly, refining the direct injection phase is of great help to inner SNCR technology to enhance the reduction of NOx and reduce NH3 oxidation and NH3 slipping.