A kind of evaluation method of scr catalyst of selective catalytic reduction technology

Abstract

The invention discloses an evaluation method for a selective catalytic reduction technology SCR catalyst. The evaluation method particularly comprises that a fresh catalyst is arbitrarily sampled, three samples are intercepted respectively at an inlet section, a middle section and an outlet section of an aged catalyst, and the average of sample evaluation results is used as a parameter finally reflecting the catalyst performance. Each temperature point on a flow reactor is evaluated by the steps: firstly, introducing NO, O2, CO2 and N2, and real-timely recording the amount of produced NO2 and changes thereof, to obtain the NO oxidation rate and the NOX balance time; then adding excess NH3, to obtain the NOX conversion rate, the NH3 escape rate and the NH3 balance time; subsequently, purging with N2, getting ready to enter the next temperature point, and evaluating; and finally obtaining the NOX conversion rate, the NH3 escape rate, the NO oxidation rate, the NH3 and NOX balance time and other parameters of the catalyst in the whole temperature window, to compare good or bad of the performance of the catalyst. The whole evaluation method has high combination degree with a real vehicle, and improves the status of more and disunity SCR catalyst evaluation indexes and lack of systematic evaluation process.

Description

technical field [0001] The invention relates to a catalyst evaluation method, especially for the evaluation method of selective catalytic reduction technology SCR catalyst, which can systematically evaluate the selective catalytic reduction technology SCR catalyst used in engine tail gas treatment, flue gas denitrification and the like. Background technique [0002] With people's emphasis on environmental protection and increasingly stringent emission regulations, selective catalytic reduction technology SCR has become the current X One of the most effective technical means, it has been widely used in engine exhaust treatment, flue gas denitrification and other occasions. There are many studies on SCR catalysts, but there are few unified evaluation indicators. of which NO X Conversion rate is the most commonly used evaluation index. In addition, NH 3 Oxidation rate, N 2 Selectivity of NH 3 escape rate, NO oxidation rate, NO 2 reduction rate, N 2 The generation rate of...

AI Technical Summary

Problems solved by technology

Although the "four-step method" is comprehensive, it is complicated to operate and requires multiple sets of instruments to complete, and the purpose is to establish a SCR flow response model rather than to evaluate

[0005] In addition, due to uneven exhaust and axial changes in flow velocity in real vehicles, the aging degree of SCR reactors is not uniform, and this phenomenon has not been included in the evaluation index.

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