Formation and Measurement of the Porosities, Tensile Strengths, and Deformation Coefficients of Gasification Filter Cakes at Operating Temperatures and Pressures

Kono, Hisashi; Jordan, Bill; Ohtake, Takaaki; Smith, Duane H.

doi:10.1080/02786829808965566

“…The phenomenon of lter clogging and/or particle dendrite growth has been observed in a number of studies (Brown and Wake 1999;Payatakes and Tien 1976;Kono et al 1998;Sioutas et al 1999;Thomas et al 1999;Walsh and Stenhouse 1997;Barrett and Rousseau 1998;Ferer and Smith 1998;Smith et al 1998). The factors in uencing the speci c dust cake resistance coef cient, K 2 , include the ltration velocity (Cheng and Tsai 1998;Dennis and Dirgo 1981;Dennis and Durham 1979;Spaite and Walsh 1963), the particle shape, and the size distribution of the challenge particles (Cheng and Tsai 1998;Japuntich et al 1994).…”

Section: Introductionmentioning

confidence: 99%

Experimental Study on the Loading Characteristics of Needlefelt Filters with Micrometer-Sized Monodisperse Aerosols

Chen

¹

,

Chen

²

,

Huang

³

et al. 2001

Aerosol Science and Technology

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In this work, three types of needlefelt lters, made of Polyester (PE), Ryton Sulfar (RS), and Polyaramid (PA), were tested to investigate the aerosol loading characteristics of fabric lters when challenged with micrometer-sized monodisperse potassium sodium tartrate (PST) particles. A brous lter with packing density of 9%, thickness of 0.38 mm, and ber diameter of 5.1 µ m was included for comparison. A vibrating ori ce monodisperse aerosol generator was used to produce three different sizes (5, 10, and 20 µ m) of PST particles for aerosol loading experiment. An ultrasonic atomizing nozzle and a TSI constant output nebulizer were used to generate polydisperse PST particles for the aerosol penetration test. The aerosol penetration of submicrometer-sized particles through the lters was measured by using a Scanning Mobility Particle Sizer. An Aerodynamic Particle Sizer was used to measure the penetration fraction of aerosol particles larger than 0.8 µ m. The pressure drop across the lter was monitored by using pressure transducers, which were calibrated against an inclined manometer. Air ows of 5, 10 , 20, and 30 cm/s were used to study the ow dependency. The aerosol penetration results showed that the particles larger than 3 µ m did not penetrate the clean fabric lters tested in the present study. The loading curves (plots of pressure drop against sampling time) displayed three regions: an initial region of fast increase, a transition region, and a nal linear region after the dust formation point. After the formation point of the dust cake, both fabric and brous lters shared the same slope (of the loading curves). The slope of different regions of the loading curves was determined by many factors, such as size of challenge aerosol, face velocity, surface treatment, and the compressibility of the dust cake forming on the lter. The method of nal surface treatment was found to be critical to the performance of the fabric lters. In order to avoid the unnecessary rise in air resistance, the melting clumps formed during nal surface treatment should be as thin and narrow as possible, just enough to support the lter bag cleaning. From the standpoint of lter quality and energy consumption, the low ltration velocity has to be adopted whenever possible, because high ltration velocity not only led to lower lter quality (in particular for submicrometer-sized particles) but also created dust cake of lower porosity, which caused an extra rise in pressure drop across the dust cake.

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“…The phenomenon of lter clogging and/or particle dendrite growth has been observed in a number of studies (Brown and Wake 1999;Payatakes and Tien 1976;Kono et al 1998;Sioutas et al 1999;Thomas et al 1999;Walsh and Stenhouse 1997;Barrett and Rousseau 1998;Ferer and Smith 1998;Smith et al 1998). The factors in uencing the speci c dust cake resistance coef cient, K 2 , include the ltration velocity (Cheng and Tsai 1998;Dennis and Dirgo 1981;Dennis and Durham 1979;Spaite and Walsh 1963), the particle shape, and the size distribution of the challenge particles (Cheng and Tsai 1998;Japuntich et al 1994).…”

Section: Introductionmentioning

confidence: 94%

Experimental Study on the Loading Characteristics of Needlefelt Filters with Micrometer-Sized Monodisperse Aerosols

Chen¹,

Chen²,

Huang³

et al. 2001

Aerosol Science and Technology

View full text Add to dashboard Cite

In this work, three types of needlefelt lters, made of Polyester (PE), Ryton Sulfar (RS), and Polyaramid (PA), were tested to investigate the aerosol loading characteristics of fabric lters when challenged with micrometer-sized monodisperse potassium sodium tartrate (PST) particles. A brous lter with packing density of 9%, thickness of 0.38 mm, and ber diameter of 5.1 µ m was included for comparison. A vibrating ori ce monodisperse aerosol generator was used to produce three different sizes (5, 10, and 20 µ m) of PST particles for aerosol loading experiment. An ultrasonic atomizing nozzle and a TSI constant output nebulizer were used to generate polydisperse PST particles for the aerosol penetration test. The aerosol penetration of submicrometer-sized particles through the lters was measured by using a Scanning Mobility Particle Sizer. An Aerodynamic Particle Sizer was used to measure the penetration fraction of aerosol particles larger than 0.8 µ m. The pressure drop across the lter was monitored by using pressure transducers, which were calibrated against an inclined manometer. Air ows of 5, 10 , 20, and 30 cm/s were used to study the ow dependency. The aerosol penetration results showed that the particles larger than 3 µ m did not penetrate the clean fabric lters tested in the present study. The loading curves (plots of pressure drop against sampling time) displayed three regions: an initial region of fast increase, a transition region, and a nal linear region after the dust formation point. After the formation point of the dust cake, both fabric and brous lters shared the same slope (of the loading curves). The slope of different regions of the loading curves was determined by many factors, such as size of challenge aerosol, face velocity, surface treatment, and the compressibility of the dust cake forming on the lter. The method of nal surface treatment was found to be critical to the performance of the fabric lters. In order to avoid the unnecessary rise in air resistance, the melting clumps formed during nal surface treatment should be as thin and narrow as possible, just enough to support the lter bag cleaning. From the standpoint of lter quality and energy consumption, the low ltration velocity has to be adopted whenever possible, because high ltration velocity not only led to lower lter quality (in particular for submicrometer-sized particles) but also created dust cake of lower porosity, which caused an extra rise in pressure drop across the dust cake.

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Evaluation of a Novel Granular Bed Filtration System for High Temperature Applications

Risnes

¹

,

Sønju

²

2001

Progress in Thermochemical Biomass Conversion

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Formation and Measurement of the Porosities, Tensile Strengths, and Deformation Coefficients of Gasification Filter Cakes at Operating Temperatures and Pressures

Cited by 11 publications

References 9 publications

Experimental Study on the Loading Characteristics of Needlefelt Filters with Micrometer-Sized Monodisperse Aerosols

Experimental Study on the Loading Characteristics of Needlefelt Filters with Micrometer-Sized Monodisperse Aerosols

Experimental Study on the Loading Characteristics of Needlefelt Filters with Micrometer-Sized Monodisperse Aerosols

Evaluation of a Novel Granular Bed Filtration System for High Temperature Applications

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