SCRF降低柴油机NO_x和颗粒物排放的数值模拟
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- 英文论文题名：Numerical Simulation of Diesel SCRF System Reducing NO_x and PM
- 论文作者：苏庆运 ; 付细平 ; 冯廷智
- 英文论文作者：Qingyun Su ; Xiping Fu ; Tingzhi Feng ; Institute of Internal Combustion Engine ; Dalian University of Technology
- 年：2016
- 作者机构：大连理工大学能源与动力学院内燃机研究所;
- 论文关键词：柴油机 ; 氮氧化物 ; 颗粒物 ; 选择性催化还原 ; 碳烟氧化
- 会议召开时间：2016-07-01
- 会议录名称：中国化学会第30届学术年会摘要集-第四十六分会：燃烧化学
- 语种：中文
- 分类号：X701;O643.3
- 学会代码：ZGHY
- 会议名称：中国化学会第30届学术年会-第四十六分会 ; 燃烧化学
- 会议地点：中国辽宁大连
- 主办单位：中国化学会
- 学会名称：中国化学会
- 页数：1
- 文件大小：288k
- 原文格式：D
- 会议级别：全国
摘要
SCRF是将选择性催化还原SCR催化剂涂覆到壁流式微粒过滤器内,能同时降低柴油机NO_x和颗粒物排放的集成式后处理装置。为了探究SCRF内Cu分子筛催化剂表面的NO_x转化过程,建立了壁流式SCR总包反应动力学模型。对NH_3吸附和脱附反应的模拟结果如图1a所示,表明采用Eley-Rideal机理的单吸附位模型能较好地预测NH_3的程序升温脱附过程。图1b所示为不同温度条件下的稳态NO_x转化率,模拟值与实验值吻合良好。600℃时模拟值与实验值出现约5%的偏差,这是由于尾气中的水分会影响NH_3氧化速率,进而影响整体的NO_x转化率~[1]。基于壁流式SCR反应模型发展了双层碳烟氧化模型,模拟了碳烟氧化过程中反应器出口含碳产物的浓度变化情况,结果如图1c所示。在Cu的催化作用下~[2],碳烟氧化反应能在较低的温度(300℃)下开始发生。从图1看出本文所建的SCRF模型能较好地预测文献中实验结果~[3]。
The SCRF system incorporates SCR catalyst into a wall-flow filter as a single device which can remove PM and NO_x from diesel engine exhaust gases simultaneously. The kinetic model of wall-flow SCR was established, and the adsorption and desorption of NH_3 were considered. Results show that the single site adsorption model based on Eley-Rideal mechanism can reproduce the adsorption and desorption processes of NH_3 well. The simulated steady-state NO_x conversion is in good agreement with experimental data, and the discrepancy of 5% at 600℃ is due to the inhibiting effect of water vapor on NH_3 oxidation. Since Cu-zeolite is the catalytic material for soot oxidation, the established dual layer soot oxidation model can capture the regeneration process, and the soot oxidation starts at a lower temperature(300℃).
The SCRF system incorporates SCR catalyst into a wall-flow filter as a single device which can remove PM and NO_x from diesel engine exhaust gases simultaneously. The kinetic model of wall-flow SCR was established, and the adsorption and desorption of NH_3 were considered. Results show that the single site adsorption model based on Eley-Rideal mechanism can reproduce the adsorption and desorption processes of NH_3 well. The simulated steady-state NO_x conversion is in good agreement with experimental data, and the discrepancy of 5% at 600℃ is due to the inhibiting effect of water vapor on NH_3 oxidation. Since Cu-zeolite is the catalytic material for soot oxidation, the established dual layer soot oxidation model can capture the regeneration process, and the soot oxidation starts at a lower temperature(300℃).
引文
[1]Lietti L.,Nova I.,Forzatti P.Top.Cata.2000,11(1),111.
[2]Murphy M.,Hillenbrand L.,Trayser D.,Wasser J.1981,SAE Paper 810112.
[3]Tan J.,Solbrig C.,Schmieg S.J.2011,SAE Paper 2011-01-1140.
[2]Murphy M.,Hillenbrand L.,Trayser D.,Wasser J.1981,SAE Paper 810112.
[3]Tan J.,Solbrig C.,Schmieg S.J.2011,SAE Paper 2011-01-1140.