Question 8.8: Pneumatic Conveyor Describe the operation of a pneumatic co......

Solved Practical Problems in Fluid Mechanics [1011255]

Pneumatic Conveyor

Describe the operation of a pneumatic conveyor.

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Pneumatic conveying is the transportation of granular free-flowing particulates such as grains and catalyst particles that are suspended in a fast-moving flow of air or gas. The particles move freely and can be readily transported to and from hoppers and silos through pipes and ducts, which may be circular in cross section or of some other geometry and may be made of various materials including plastic tubing. However, the risk of static electricity, which may lead to ignition of the particles being transported, needs to be carefully considered. The flow may be caused by a blower or compressor upstream of the feed point or may operate with a negative pressure with the blower or compressor located downstream. For low gauge pressure transportation, a Roots blower is typically used. This is a type of compressor used to transport large volumes of gas and consists of two rotating lobe-type rotors which have a small clearance between the rotors and the casing.

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