Aggregation of fine ash into larger particles benefits fly ash removal in an electrostatic precipitator.Thermal aggregation,turbulent aggregation,and electrical aggregation of fine ash (derived from co-firing of bioma...Aggregation of fine ash into larger particles benefits fly ash removal in an electrostatic precipitator.Thermal aggregation,turbulent aggregation,and electrical aggregation of fine ash (derived from co-firing of biomass fuel and anthracite coal) was simulated under different conditions in an electrostatic precipitator.A population balance model and user-defined function in Fluent were assumed to obtain aggregation kernel functions and calculate the aggregation effects on the co-combusted particles.The results show that electrical aggregation had an obvious effect on both micron-and submicron-sized particles.For submicron particles,the effect of thermal aggregation is about ten times greater than turbulent aggregation.Meanwhile,for micron-sized particles,turbulent aggregation is about seven times greater than thermal aggregation.Therefore,particle aggregation in the electrostatic precipitator mainly occurs because of electrical aggregation,supplemented by thermal aggregation and turbulent aggregation.When the flow velocity is 1.0 m/s,particle volume fraction is 1.4%,and biomass co-firing ratio is 10%,the effects of all three aggregation processes on ash particles are optimized.展开更多
随着我国环保标准日益严格,很多燃煤电厂静电除尘器已不能满足排放标准的要求,需进行改造。该文首先分析了造成静电除尘器除尘效率低下的主要原因;提出3种改造方案:增加电场;改造为袋式除尘器;改造为静电袋式复合除尘器。并从技术性能...随着我国环保标准日益严格,很多燃煤电厂静电除尘器已不能满足排放标准的要求,需进行改造。该文首先分析了造成静电除尘器除尘效率低下的主要原因;提出3种改造方案:增加电场;改造为袋式除尘器;改造为静电袋式复合除尘器。并从技术性能和经济性2个方面对3种改造方案进行了比较,以郑州热电厂200 M W机组静电除尘器改造为例对3种方案进行了对比分析,结果表明:改造为静电袋式复合除尘器的方案是静电除尘器改造的最佳方案,并认为静电袋式复合除尘是我国除尘技术未来的发展方向之一。展开更多
基金the National Natural Science Foundation of China(Grant No.51376063).
文摘Aggregation of fine ash into larger particles benefits fly ash removal in an electrostatic precipitator.Thermal aggregation,turbulent aggregation,and electrical aggregation of fine ash (derived from co-firing of biomass fuel and anthracite coal) was simulated under different conditions in an electrostatic precipitator.A population balance model and user-defined function in Fluent were assumed to obtain aggregation kernel functions and calculate the aggregation effects on the co-combusted particles.The results show that electrical aggregation had an obvious effect on both micron-and submicron-sized particles.For submicron particles,the effect of thermal aggregation is about ten times greater than turbulent aggregation.Meanwhile,for micron-sized particles,turbulent aggregation is about seven times greater than thermal aggregation.Therefore,particle aggregation in the electrostatic precipitator mainly occurs because of electrical aggregation,supplemented by thermal aggregation and turbulent aggregation.When the flow velocity is 1.0 m/s,particle volume fraction is 1.4%,and biomass co-firing ratio is 10%,the effects of all three aggregation processes on ash particles are optimized.
文摘随着我国环保标准日益严格,很多燃煤电厂静电除尘器已不能满足排放标准的要求,需进行改造。该文首先分析了造成静电除尘器除尘效率低下的主要原因;提出3种改造方案:增加电场;改造为袋式除尘器;改造为静电袋式复合除尘器。并从技术性能和经济性2个方面对3种改造方案进行了比较,以郑州热电厂200 M W机组静电除尘器改造为例对3种方案进行了对比分析,结果表明:改造为静电袋式复合除尘器的方案是静电除尘器改造的最佳方案,并认为静电袋式复合除尘是我国除尘技术未来的发展方向之一。