Pneumatics - Solid Transports and Separator Types

[Esam]

In a pneumatic transport system, solids as dust, flour, sugar, sand and many other products, are transported in high speed air flows.
The table below can be used as an indication of minimum particle sizes recommended for the different types of separators.

Separator Principle	Minimum Particle Size (micron)
Gravity	200
Inertial	50-150
Centrifugal, large diameter cyclone	40-60
Centrifugal, small diameter cyclone	20-30
Fan type	15-30
Filter	0.5
Scrubber	0.5-2.0
Electrical	0.001-1.0

• 1 micron = 0.001 mm

[Esam]

[h=Pneumatics - Solid Transports and Particle Sizes]1[/h]
The table below can be used as an indication of typical particle sizes of some common products.

Product	Typical Particle Size (micron)
Outdoor dust	0.5
Sand blasting	1.4
Foundry dust	1.0 - 200
Granite cutting	1.4
Coal mining	1.0
Raindrops	500 - 5000
Mist	40 - 500
Fog	1 - 40
Fly ash	3 - 70
Pulverized coal	10 - 400

• 1 micron = 0.001 mm

[Esam]

[h=Pneumatic transport systems may be suited to move powder and other solid products]2[/h]
Some common solids as flour, sugar, cement and many more, can be suspended and transported in air - referred as pneumatic conveying. A pneumatic conveying system may transport solids up to approximately 50 mm size. The powder or solid must be dry, with no more than 20% moisture and not sticking.
In a pneumatic conveying system, most of the energy is used for the transport of the air itself. The energy efficiency of a pneumatic conveying plant is therefore relatively low, but this is often outweighed by easy handling and, in well designed systems, dust free solutions.
In general the length of a pneumatic system should not extend 300 m for each pneumatic unit. The products can be conveyed over long distances by connecting the systems in series.
There are three basic designs of pneumatic transport systems:

• dilute phase conveying at a high gas speeds (20 - 30 m/s)
• strand conveying at a limited gas speeds (15 - 20 m/s)
• dense phase conveying at a low gas speeds (5 - 10 m/s)

Pneumatic systems can operate with both positive and negative pressures - vacuum. The working pressure should not extend 40 kN/m².
The maximum temperature rise during pneumatic compression is seldom above 5^oC, which makes pneumatic transport systems suitable to sensitive products as ********s, food or similar.

[Munich]

Hi Esam,
Thanks for tips. I am doing a prelim. line sizing for gas-solid fluid sys. (Pneumatic conveying) and since I am new to this, I appreciate any help on that.

Regards

[Lennart]

Where Do I need software for pneumatic transport design (like pneuDesign)? tank you