本文在分子动力学模拟基础上采用了考虑黏附作用的JKR理论取代传统Hertz理论作为颗粒间作用力,并吸取了DEM中滑动摩擦、滚动摩擦和扭动摩擦的思想建立一种细颗粒碰撞和团聚过程的多时间尺度粒子动力学模拟方法.成功地实现了颗粒在纤维...本文在分子动力学模拟基础上采用了考虑黏附作用的JKR理论取代传统Hertz理论作为颗粒间作用力,并吸取了DEM中滑动摩擦、滚动摩擦和扭动摩擦的思想建立一种细颗粒碰撞和团聚过程的多时间尺度粒子动力学模拟方法.成功地实现了颗粒在纤维上沉积过程的模拟,结果表明微米颗粒的Van der Waals力量纲约是曳力2~10倍,中心流线附近颗粒更易于在纤维上沉积,初始沉积的颗粒则会在纤维上形成"遮挡"效应。展开更多
Coal-fired power plants are considered a major source of fine particle emissions in China.Aimed to improve the removal efficiency of fine particles during the limestone-gypsum wet flue gas desulfurization(WFGD) proces...Coal-fired power plants are considered a major source of fine particle emissions in China.Aimed to improve the removal efficiency of fine particles during the limestone-gypsum wet flue gas desulfurization(WFGD) process, a novel technology using chemical agglomeration to abate the emission of fine particles is presented herein. The relationship between fine particle emission and the proportion of fine particles in the desulfurization slurry was studied.Additionally, the influence of chemical agglomeration on fine particle size distribution, both in the flue gas and slurry was experimentally investigated. When chemical agglomeration agents were added to the desulfurization slurry, the fine particle removal performance as well as the effects of the operation parameters was also explored via the simulated experimental facility.The results revealed that the fine particles in both the desulfurization slurry and flue gas were significantly enlarged after the addition of the agglomeration agents. This was more marked in the submicron particles. Thus, the proportion of fine particles(< 10 μm) in the slurry decreased from 31.1% to 22.6%. An increase in the desulfurization slurry temperature and liquid-to-gas ratio aided the reduction in fine particle emission. Moreover, the addition of an agglomeration agent in the slurry did not affect the desulfurization efficiency of the desulfurization tower and even promoted the WFGD process. Thus, the proposed chemical agglomeration technique reduced the fine particle emission of the WFGD system by ~30%, while a desulfurization efficiency >90% was maintained.展开更多
文摘本文在分子动力学模拟基础上采用了考虑黏附作用的JKR理论取代传统Hertz理论作为颗粒间作用力,并吸取了DEM中滑动摩擦、滚动摩擦和扭动摩擦的思想建立一种细颗粒碰撞和团聚过程的多时间尺度粒子动力学模拟方法.成功地实现了颗粒在纤维上沉积过程的模拟,结果表明微米颗粒的Van der Waals力量纲约是曳力2~10倍,中心流线附近颗粒更易于在纤维上沉积,初始沉积的颗粒则会在纤维上形成"遮挡"效应。
基金supported by the National Key Research and Development Program of China (No. 2016YFB0600602)
文摘Coal-fired power plants are considered a major source of fine particle emissions in China.Aimed to improve the removal efficiency of fine particles during the limestone-gypsum wet flue gas desulfurization(WFGD) process, a novel technology using chemical agglomeration to abate the emission of fine particles is presented herein. The relationship between fine particle emission and the proportion of fine particles in the desulfurization slurry was studied.Additionally, the influence of chemical agglomeration on fine particle size distribution, both in the flue gas and slurry was experimentally investigated. When chemical agglomeration agents were added to the desulfurization slurry, the fine particle removal performance as well as the effects of the operation parameters was also explored via the simulated experimental facility.The results revealed that the fine particles in both the desulfurization slurry and flue gas were significantly enlarged after the addition of the agglomeration agents. This was more marked in the submicron particles. Thus, the proportion of fine particles(< 10 μm) in the slurry decreased from 31.1% to 22.6%. An increase in the desulfurization slurry temperature and liquid-to-gas ratio aided the reduction in fine particle emission. Moreover, the addition of an agglomeration agent in the slurry did not affect the desulfurization efficiency of the desulfurization tower and even promoted the WFGD process. Thus, the proposed chemical agglomeration technique reduced the fine particle emission of the WFGD system by ~30%, while a desulfurization efficiency >90% was maintained.