This study is devoted to the explanation of different characteristics of magnetic filtration and the way these characteristics affect the important filtration parameters. Magnetic fields in pores and the force effect ...This study is devoted to the explanation of different characteristics of magnetic filtration and the way these characteristics affect the important filtration parameters. Magnetic fields in pores and the force effect of these fields on magnetic particles and the magnetization properties of packed beds composed of ferromagnetic spheres and metal chips are evaluated. The profile of accumulation and capture regions of the particles, the variation of the fluid velocity in these regions and analytic expressions of particle capture radius are presented. The effects of filtration regime parameters on magnetic filter performance were investigated. An analytical expression has been obtained for the dependence of the logarithmic efficiency coefficient on filtration velocity, the geometry of filter elements, the particle size and other parameters of filtration. The stationary and non-stationary equations of the magnetic filtration processes are given. An expression of magnetic filter performance is shown with dimensionless parameters obtained from the filtration system. These relations are useful for calculations in engineering practice, including the design of magnetic filters, provision of suggestions on construction, and optimization and control of filter operation.展开更多
The effects of the filtering granule particle size and filtration superficial velocity on the dust particle size distribution in different layers of a granular bed system are discussed herein.A multilayer drawer granu...The effects of the filtering granule particle size and filtration superficial velocity on the dust particle size distribution in different layers of a granular bed system are discussed herein.A multilayer drawer granular bed filtration system was designed for these experiments based on filtering fly ash from a power plant.After a 1-h experiment,47.8% of dust particles smaller than 2.5μm,63.7% of dust particles smaller than 10μm,and 39.1% of dust particles larger than 10μm were captured by the granular bed(corresponding to initial volume fractions of 6%,19.3%,and 80.7%,respectively).Large dust particles were more easily trapped by the granular bed than small dust particles.Increasing the size of the filter granules and increasing the superficial velocity of the inlet flue gas were both effective ways to enhance the dust-holding capacity of the granular media throughout the granular bed.展开更多
文摘This study is devoted to the explanation of different characteristics of magnetic filtration and the way these characteristics affect the important filtration parameters. Magnetic fields in pores and the force effect of these fields on magnetic particles and the magnetization properties of packed beds composed of ferromagnetic spheres and metal chips are evaluated. The profile of accumulation and capture regions of the particles, the variation of the fluid velocity in these regions and analytic expressions of particle capture radius are presented. The effects of filtration regime parameters on magnetic filter performance were investigated. An analytical expression has been obtained for the dependence of the logarithmic efficiency coefficient on filtration velocity, the geometry of filter elements, the particle size and other parameters of filtration. The stationary and non-stationary equations of the magnetic filtration processes are given. An expression of magnetic filter performance is shown with dimensionless parameters obtained from the filtration system. These relations are useful for calculations in engineering practice, including the design of magnetic filters, provision of suggestions on construction, and optimization and control of filter operation.
基金the support of the National Key Research and Development Program of China(grant No.2018YFB0605903).
文摘The effects of the filtering granule particle size and filtration superficial velocity on the dust particle size distribution in different layers of a granular bed system are discussed herein.A multilayer drawer granular bed filtration system was designed for these experiments based on filtering fly ash from a power plant.After a 1-h experiment,47.8% of dust particles smaller than 2.5μm,63.7% of dust particles smaller than 10μm,and 39.1% of dust particles larger than 10μm were captured by the granular bed(corresponding to initial volume fractions of 6%,19.3%,and 80.7%,respectively).Large dust particles were more easily trapped by the granular bed than small dust particles.Increasing the size of the filter granules and increasing the superficial velocity of the inlet flue gas were both effective ways to enhance the dust-holding capacity of the granular media throughout the granular bed.
