STATIC MIXER FOR MIXING UREA SOLUTION AND ENGINE EXHAUST GAS

摘要

The present invention relates to a static mixer for mixing a urea solution and engine exhaust gas. The static mixer includes: an external tube (2) including one end portion connected to an exhaust manifold of a diesel engine, the other end portion connected to an SCR (Selective Catalytic Reduction), and a part with which a urea solution injection adaptor (5) is provided; an internal tube (3) installed inside the external tube (2) so as to have a constant gap between at least a part of an outer wall surface and an inner wall surface of the external tube (2); and a channel unit (10) comprising a plurality of guiding channels (11) provided inside the internal tube (3) in a longitudinal direction, and having a bent inlet portion (12) facing a lower end portion of the urea solution injector adaptor (5). The present invention may make the exhaust gas and the urea solution before passing through the SCR pass through the bent inlet portion and the plurality of guiding channels of the channel unit to form fine and even mixed gas, thereby largely decreasing an amount of nitride oxide (NOx) discharged to the air by improving a catalytic reduction reaction ratio in the SCR.