Free-flowing particles size range

Powdered cellulose occurs as a white or almost white, odorless and tasteless powder of various particle sizes, ranging from a free-flowing fine or granular dense powder, to a coarse, fluffy, nonflowing material. 

Pastelike materials Solids mixed with liquid to form a free-flowing paste size of particles approximately in the range 0.1-50 pm... 

Air pulse OK for free flowing and wide range in particle size i.e. one size > 3 times the other. Use when have fines with FRI < 2.2 kg/s and other components that have about the same size or are in same FRI range. OK for moderately free flowing dry solids. 

When the size of a particle approaches the same order of magnitude as the mean free path of the gas molecules, the setthng velocity is greater than predicted by Stokes law because of molecular shp. The slip-flow correc tion is appreciable for particles smaller than 1 [Lm and is allowed for by the Cunningham correc tion for Stokes law (Lapple, op. cit. Licht, op. cit.). The Cunningham correction is apphed in calculations of the aerodynamic diameters of particles that are in the appropriate size range. 

The catalytic test of propane ODH reaction was performed in the 350-600°C range in a quartz fixed bed flow reactor with on line GC analysis. The free volume of the reactor after the catalyst bed was filled with quartz particles to minimize the homogeneous reactions. All the testing set was placed in a thermostat with heated lines to the gas chromatographs at about 100°C to prevent water condensation. The feed gas composition was C3H8/02/N2 = 20/10/70 vol.% at total gas flow 50 cm3 min-1. Catalyst fractions of 0.2-0.315 mm particle size and of 80 mg weight were loaded into the reactor. Before the reaction, the catalyst samples in the reactor were kept under airflow at 600°C for lh. 

Pure alumina (A1203) is a dry, snow-white, free-flowing crystalline powder and may be obtained in a wide range of particle sizes. 

Ancillaries include a micro-volume module, a hazardous fluid module and a dry powder module. Their small volume module uses less than 125 ml of diluent. The micro volume module has a total volume of 12 ml this has an internal stirring mechanism to keep particles suspended during analyses. The automatic hazardous fluids module can be supplied with a microtip eight power ultrasonic probe to keep the particles dispersed. The dry powder module analyzes both free flowing and cohesive powders covering the size range from 0.375 pm to 2000 pm. 

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