| 摘要 |
<p>The invention relates to a reducing agent addition system for adding a reducing agent upstream of an exhaust gas catalyst (8) arranged in an exhaust pipe (9) of an internal combustion engine, and a method for preparing a reducing agent for catalytic exhaust gas purification and for adding the same to an exhaust pipe (9) of an internal combustion engine. The reducing agent addition system comprises a reducing agent dosing and mixing unit (1) to which a reducing agent and compressed gas can be supplied, and which comprises a reducing agent dosing valve (11) and a mixing chamber (5) for producing a reducing agent/gas mixture, an addition nozzle (7) for adding the reducing agent/gas mixture to the exhaust pipe (9), and a mixture line (6) connecting the mixing chamber (5) to the addition nozzle (7), said mixture line being embodied in such a way that it can be heated (6). According to the inventive method, a reducing agent/gas mixture produced in a mixing chamber (5) of a reducing agent dosing and mixing unit (1) is supplied to an addition nozzle (7) arranged in the exhaust pipe (9), the reducing agent/gas mixture being heated during the supply to the addition nozzle (7). The invention is preferably used in exhaust gas purification installations of internal combustion engines, especially commercial vehicles.</p> |
