Flow Tests of Filter Media in Two-dimensional Model of Granular Moving-bed Filter with Louvers and Sublouvers
Granular moving bed filters for hot gas cleanup continue to be developed as a key component of current Integrated Gasification Combined Cycle (IGCC) and Pressurized Fluidized-Bed Combustion (PFBC) power generation systems.They are considered as alternative technologies to rigid ceramic candle filters.In the case of filtration in granular moving bed,the gas-entrained particulates and chemical impurities are collected both inside and on the upstream surface of the bed.As concentration of dust in gas changes in time and according to efficiency of combustion or gasification,the effort exists to increase the velocity of moving bed on inlet (dirty) side of filter in comparison with outlet (clean) side of filter.It is believed that faster withdrawal of dust on upstream surface of granular bed will keep stable efficiency of filtration without undesirable oscillations of gas pressure drop.Granular moving bed with a series of louvers and sub-louvers enables separation of granular moving bed into three streams.In this contribution we will present the experiments with flow of filter granules in two-dimensional systems with louvers only and with louvers and sublouvers.There were two parts of experimental tests.The first was the observation on the flow patterns of filter media (silica sand) in the whole moving bed.A digital video camera recorder was used to record the development of the flow of colored tracer sands.The second part of experiments was the velocity measurements.Colored tracers were uniformly distributed in granular moving bed.The digital video camera was used to record movement of tracers.The flow images could then be transferred and stored in a personal computer.By identifying the positions of every tracer particle in the consecutive images,the tracer displacement could be measured directly from the images.Dividing the displacements by the time between two images the individual tracer velocities could be found.We found that sublouvers designed according to flow properties of granular filter media and in agreement with theory for mass flow of granular media in plane hopper system are able to make flow uniform and diminish stagnant zones near louver walls
moving granular bed:louvered walls:sublouvers:gas filtration:high-temperature gas cleanup
S S Hsiau J Smid Y P Chyou
Department of Mechanical Engineering,National Central University,No.300,Jungda Road,Jhongli 32001,Ta Institute of Nuclear Energy Research,Atomic Research Council,No.1000,Wenhua Rd.,Longtan Township,Tao
国际会议
The 8th International Symposium on Gas Cleaning at High Temperatures(第八届国际高温气体净化技术研讨会 GCHT-8)
太原
英文
141-149
2010-08-23（万方平台首次上网日期，不代表论文的发表时间）