催化型柴油颗粒捕集器再生性能的试验研究

Experimental Study on Regeneration Performance of Catalytic Diesel Particulate Filter

为探究催化型柴油机颗粒捕集器(catalytic diesel particulate filter,CDPF)的再生性能,自制了CDPF颗粒加载装置,通过模拟气试验平台研究了炭载量、再生温度及气体流量对CDPF再生性能的影响,并对其再生效率、再生效能比、最高温度及最高温度梯度性能指标进行评价。试验结果表明:CDPF再生过程主要有两个阶段,第一个阶段主要发生在250~400℃之间,为低温长时间再生阶段;第二个阶段主要发生在500~600℃之间,为高温短时间再生阶段。当再生温度为350℃、气体流量为200mL/min时,3.2g/L、5.0g/L和7.0g/L 3种炭载量下的最高温度梯度均达到最小,分别为2 737.5℃/m、4 387.5℃/m和3 837.5℃/m。其再生效率在再生温度为250℃时均约为6.0%,而在550℃时均达到85.6%。当炭载量为5.0g/L,再生温度为500℃和550℃,气体流量为300mL/min时,最高温度、最高温度梯度及再生效率均达到最大,再生效能比随气体流量的增大从4.6×10-5 J-1下降到1.8×10-5 J-1。

In order to explore the regeneration performance of catalytic diesel particulate filter(CDPF),an in-house-made CDPF carbon particle loading device was developed.The effects of carbon loading,regeneration temperature and gas flow rate on the regeneration performance of CDPF were studied through a simulated gas test platform,and the regeneration efficiency,regeneration efficiency ratio,maximum temperature and maximum temperature gradient were evaluated.The results show that there are two main stages in the CDPF regeneration.The first stage mainly takes place between 250℃ and 400℃,which is a long regeneration at low temperatures;the second stage mainly occurrs between 500℃ and 600℃,which is a short regeneration at high temperatures.When the regeneration temperature is 350℃ and the gas flow rate is 200 mL/min,the maximum temperature gradients of 3.2 g/L,5.0 g/L and 7.0 g/L carbon loading are the smallest,being 2 737.5℃/m,4 387.5℃/m and 3 837.5℃/m respectively.The regeneration efficiency is about 6% at 250℃,and 85.6% at 550℃.When the carbon loading is 5.0 g/L,the regeneration temperature is 500℃and 550℃ and the gas flow rate increases to 300 mL/min,the maximum temperature,the maximum temperature gradient and the regeneration efficiency all reach the highest,and the regeneration efficiency ratio decreases from 4.6×10-5 J-1 to 1.8×10-5 J-1 with the increase in the gas flow rate.