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Optimisation of a Urea Selective Catalytic Reduction System with a Coated Ceramic Mixing Element
M.A. Damm1, M. Sauerborn1, T. Fend2, U. Herrmann1
1 Solar-Institut Jülich (SIJ), FH Aachen University of Applied Sciences
2 Institute for Solar Research, Facilities and Solar Materials
received August 1, 2016, received in revised form October 3, 2016, accepted November 4, 2016
Vol. 8, No. 1, Pages 19-24 DOI: 10.4416/JCST2016-00056
Abstract
The selective catalytic reduction of NOx emissions to H2O and N2 is a major technology in automotive applications for exhaust gas aftertreatment. In this process, the reactant ammonia (NH3) is produced by injecting AdBlue®. With the help of an SCR catalyst, this NH3 reduces emitted NOx to non-toxic nitrogen (N2) and water (H2O). For the homogenization and evaporation of the urea solution, usually metallic mixing elements are used. The new approach uses a mixing element based on structured porous ceramic with an enlarged surface and a special catalytic coating. The Solar-Institut Jülich and the German Aerospace Centre have developed a manufacturing process to modify and optimise the structure of basic polyurethane foams to achieve a high NH3 conversion rate in combination with adjustable backpressure. The optimised flow dynamics of the exhaust gas and the additional special catalytic coating lead to a high-performance mixing element. As a consequence, the size of the conventional SCR catalyst, which is located downstream of the mixer, can be reduced. This leads to cost-efficient and compact exhaust gas aftertreatment. In this paper the experimental results of the performance analysis of this newly designed porous-ceramic-coated mixing element will be presented.
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Keywords
Selective catalytic reduction system, selective catalytic reduction catalyst, mixing element, porous ceramic polyurethane foam
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