【作者】 颜翠平；

【导师】 刘桂建； 陈海焱；

【作者基本信息】 中国科学技术大学 ， 环境科学， 2014， 博士

【摘要】 褶皱式滤筒除尘器与同样占地面积的平式滤袋除尘器相比具有更大的过滤面积,因而得到越来越多的工厂在控制颗粒物排放和回收有价值的颗粒物方面的应用。但是褶皱式滤筒由于皱褶数量多导致无效的清灰或不完全清灰一直是其广泛运用的障碍。因此,研究脉冲喷吹褶皱式滤筒的清灰效果是推进滤筒除尘器应用的主要手段之一,探索脉冲喷吹滤筒的清灰机理能有效解决滤筒除尘器不完全清灰的问题,促进滤筒除尘器在更多的工业领域中应用。本文以脉冲喷吹褶皱式滤筒为研究对象,利用扫描电镜、压力传感器、高速摄影仪等手段测试滤筒用滤料的微观结构、滤筒侧壁压力、清灰的动态过程,结合环境科学、流体力学等理论方法,对滤筒侧壁压力的变化规律及滤筒的清灰机理等科学问题进行了研究。通过研究得出：(1)以具有代表性的2种微观结构的滤料为研究对象,分析了2种微观结构的滤料在使用过程中的差异性,揭示了2种微观结构的滤料与收集粉尘颗粒和清灰效果的关系。(2)通过褶皱比高、过滤面积大的滤筒(ΦD325×Φ215×1000mm)的侧壁压力的测定,对比研究了操作参数和工况参数不同下滤筒侧壁压力的变化,探讨了滤筒清灰效果与侧壁压力峰值的关系,从而揭示了滤筒侧壁压力在整个滤筒长度方向的变化规律及其与各个影响因素的关系。(3)通过高速摄影仪拍摄滤筒清灰的动态过程,分析引起清灰过程的脉冲气流变化特点,揭示滤筒清灰动态过程与脉冲气流变化的关系。(4)基于滤筒清灰动态过程和滤筒侧壁压力变化过程的实验结果,对比分析了滤筒与滤袋清灰的动态变化过程及压力峰值与清灰效果的规律,并结合实验室研究的结果与滤筒工业生产使用中的差异性,揭示对滤筒清灰效果贡献的主要是滤筒侧壁压力峰值及其持续时间。(5)检验滤筒侧壁压力在工业生产中的变化,根据滤筒侧壁压力的变化规律,解决滤筒除尘器收集两种不同性质的物料在工业生产中存在的问题,有效指导滤筒除尘器收集不同性质的物料。更多还原

【Abstract】 Recently, the use of pleated filter cartridges in dust collectors has attracted great attention because the pleated filter cartridges offer a larger filtration surface compared to flat-sheet filter bags (if both filters are used in housing of the same size). Therefore, dust collection technology has been used to control particulate emission and recover valuable particles in many factories. However, cleaning way of pleated filter cartridges is more difficult compared to this of the flat-sheet filter bags because of the higher pleated ratios of the filter cartridges. Deficient filter cleaning allows for shorter filtration periods and extremely shorter cleaning intervals. Thus, the pleated filter cartridge can be used to many factories through the researches on the cleaning effect and cleaning mechanism of pleated filter cartridge.Based on the pleated fabric filter cartridge, the microstructures of filter media, the surface pressures on filter cartridge and the dynamic cleaning process were determined using a scanning electron microscope, pressure transducers and a high-speed camera with a metal halide lamp. With the theory of environmental science and fluid dynamics, the scientific problems of surface pressure rules on filter cartridge and cleaning mechanisms of filter cartridge were discussed in details.The major research achievements are summarized as follows:(1) The variety behaviors of two typical kinds of media with ages using a scanning electron microscope (SEM) are obtained and to determine the effect of fabric microstructures on cake formation and dust dislodgement from filter cartridge.(2) Based on pleated filter cartridge (Φ325×Φ215×1000mm) with a higher pleat ratio and a larger filtration area, the influences of operational and conditional parameters on surface pressures on filter cartridge are discussed. The relativities of cleaning effects and peak pressures are investigated. The varied laws of pressures over the full height of filter cartridge and the relations of its and parameters are revealed.(3) The dust dislodgement from the filter cartridge is recorded using a high-speed camera. The effect of pulse airflow on cleaning process is studied. The relativity of dust dislodgement from the filter cartridge and pulse airflow is revealed.(4) Based on experimental results of dynamic cleaning process and the pressure-varied process, the dynamic cleaning process of pleated filter cartridge and filter bag are discussed in details. The laws of peak pressure and cleaning effect are obtained. With the discrepancy of experimental result and industrial application of pleated filter cartridge, the surface peak pressure and its duration on filter cartridge play an important role in dust cake dislodgement.(5) Based on the operational effects of pleated cartridge filter in industrial application, the problems of the pleated cartridge filter for collecting two different particles are resolved with the pressure laws over full height of pleated filter cartridge. This can give guidance to the application of pleated cartridge filter for collecting different particles.更多还原