Inclined piping in dense phase pneumatic conveying

Posted in: , on 2. Jul. 2002 - 16:13

The dense phase conveyor system uses dry compressed air at 5 bar(g) for conveying coke & carbon fines at a rate of 2 tons per hour through a steel pipe of 80 NB (pipe thickness is 4.5 mm). The material velocity is 5 m/s.

The coke material has following properties:

•Particle size is 0 to 1 mm.

•dry & abrasive nature.

•Angle of sliding friction between coke & steel pipe: 21°

•Hard groove index: 33 to 42

•density: 0.7 tons/cu.metre

We are utilizing the gallery portion of adjacent belt conveyor for

supporting this pipe. At the starting point, the material climbs up through the pipe along the gallery inclination of 12°.

The total conveying distance is 356 m, of which the vertical lift is 36 m. Booster air is introduced at mid conveying distance.

We would appreciate your feedback for following points:

“Whether the pneumatic conveying can be done through inclined piping, having inclination upto 15°.”


Mahesh Thota,

Mukand Limited (

biplab K. Datta - POSTEC, Norway
(not verified)

Re: Inclined Piping In Dense Phase Pneumatic Conveying

Posted on 5. Dec. 2002 - 09:45

Hello Mr Thota,

Having seen your mail today I feel the urge to reply your mail since no one has yet responded !

The answer is 'Yes' pneumatic conveying is possible in inclined pipeline as described by you !

However, I could not understand why you are adding booster air down the pipeline !!!

You claim the conveying velocity to be 5m/sec. But I guess you know that the velocity keeps on increasing as it travels the length of conveying ! Any additional air in the line will further increase the velocity leading to attrition of particles and erosion of pipelines and pipe components !!!

I shall be glad to be of any assistance to your organisation !My email address is

with best regards

Inclined Lines

Posted on 6. Dec. 2002 - 04:46

Dear friends.

Yes you can do almost anything with pneumatic conveying and get away with it.

You pay a price though.

The sloped pipeline will wear out faster than a combination vertical horizontal.

You can fall out of suspension if this was a diluted phase system, near the treshold, and present chugging and you might end out recirculating some particles after you shut down the solids feed.

Is there any way you can change the layout to go horizontal and then vertical?

like keeping your pipeline horizontal all the way to the end of the conveyor belt and then using the structure to hold the pipeline just go vertical.

It is always tempting to use the belt conveyors walkway as support for pneumatic conveying lines, it is there it is cheap. it is out of the way and it is logic. but sometimes it backfires.

Best regards

Marco Flores

TECMEN Consultant in: Sponge Iron (DRI) handling Sponge Iron DRI Automated Storage Firefighting and Root Cause Analysis Pneumatic Conveying Consultants Phone 5281 8300 4456.