Re: Pneumatic Conveying Design Queries!
Dear dineshpanta,
Your information is far from sufficient.
It seems that you are referring to a pressure system.
Particles up to 20 mm (20.000 micron) at a particle density of 2500 kg/m3 have a suspension velocity of approx. 32 m/sec, leading to an air velocity of approx. 80 m/sec.
No information is given about the dust size, nor the particle size distribution.
Then, regarding the short distance and the very low capacity, a mechanical system is likely more feasible.
best regards ■
Teus
Re: Pneumatic Conveying Design Queries!
Dear sir,
Thank you for the reply.Most of the particles have size about 90 microns. But some of the material to be conveyed are like crushed brick pieces of 20mm. Most of the volume is occupied by the dust size of about 90microns . So, we have planned to convey them by pneumatic conveying. Actually, can u help me with the calculation of my system requirements? We have calculated the saltation velocity and pressure drop in the system and proceeded accordingly. Upto what size, it would be better to convey by dilute phase pneumatic conveying?
Regards! ■
Re: Pneumatic Conveying Design Queries!
Dear dineshpanta,
We have calculated the saltation velocity and pressure drop in the system
-Assuming that you calculated the saltation velocity for the 90 micron fraction of the dust, what saltation velocity was calculated?
-Did you also calculate the saltation velocity for the 20000 micron particles and was the result?
-How did you calculate the pressure drop without knowing the pipe diameter?
As the maximum sized particles are 20 mm, (although a small, unknown fraction) the pipe diameter should be then at least 5 times this 20 mm in order to prevent blockage.
This results in a 4” pipe line.
A preliminary design could be as follows:
-particle size = 90 micron
-particle density = 2500 kg/m3
-bulk density 1062 kg/m3
-horizontal length = 26 m
-vertical length = 4 m
-pipe diameter = 4” (102 mm)
-compressor Aerzen GM015L (0.7 bar) – 4800 rpm
-blower displacement = 0.28 m3/sec
-rotary valve feeder 5 dm3 – 15 rpm – D = 0.185 m
-Filter size at receiving hopper = 25 m2
-capacity 3 tph
-pressure approx0.15 bar
-air velocity = 36 to 40 m/sec
-Solid Loading Ratio = 2.4
If you can eliminate the dust fractions above 100 micron, a smaller pipe diameter can be applied against a smaller compressor at a higher pressure.
Be aware, that this calculation is to be regarded as indicative only.
Take care ■
Teus
Re: Pneumatic Conveying Design Queries!
Originally Posted by dineshpanta
Particle size:less than 20mm(brick dust and crushed brick particles)
Particle density: 2500kg/m3
Bulk density: 1062kg/m3
Conveying distance: horizontal:26m,vertical:4m
Material flow rate: 1.8-2 tons/hr
Thank you!
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Dear Dinesh,
For this material a dense phase pneumatic conveying system will be more suitable. A dilute phase conveying system can be designed but it will not be practical.
I can design the dense phase system for you if you so wish.
Regards,
Amrit Agarwal
Pneumatic Conveying Consulting
email: polypcc@aol.com ■
Re: Pneumatic Conveying Design Queries!
Originally Posted by Teus Tuinenburg-Assuming that you calculated the saltation velocity for the 90 micron fraction of the dust, what saltation velocity was calculated?
-Did you also calculate the saltation velocity for the 20000 micron particles and was the result?
-How did you calculate the pressure drop without knowing the pipe diameter?
As the maximum sized particles are 20 mm, (although a small, unknown fraction) the pipe diameter should be then at least 5 times this 20 mm in order to prevent blockage.
This results in a 4” pipe line.
A preliminary design could be as follows:
-particle size = 90 micron
-particle density = 2500 kg/m3
-bulk density 1062 kg/m3
-horizontal length = 26 m
-vertical length = 4 m
-pipe diameter = 4” (102 mm)
-compressor Aerzen GM015L (0.7 bar) – 4800 rpm
-blower displacement = 0.28 m3/sec
-rotary valve feeder 5 dm3 – 15 rpm – D = 0.185 m
-Filter size at receiving hopper = 25 m2
-capacity 3 tph
-pressure approx0.15 bar
-air velocity = 36 to 40 m/sec
-Solid Loading Ratio = 2.4
If you can eliminate the dust fractions above 100 micron, a smaller pipe diameter can be applied against a smaller compressor at a higher pressure.
Be aware, that this calculation is to be regarded as indicative only.
Take care
Thank you so much sir! Actually, we calculated the saltation velocity and pressure drop by taking 4 inch diameter pipe because it gave us lower value of pressure drop compared to other lower dia. pipes. We wanted to use centrifugal blower for this purpose but the pressure required came out to be quite high and we also looked for roots blower(bulky and expensive). So, we have been iterating different parameters to design a working system, which is our main goal.
Obviously, the saltation velocity of 20mm particles is very high compared to that of 90microns.
Using a 6 inch pipe gave us lower pressure drop as well. According to you, the pressure required is 0.15 bar.But in our country such high pressure centrifugal blowers aren't available. SO, would you please suggest me a system that is feasible and it can work with centrifugal blower as well.
Upto what size of particles can we blow efficiently? If larger size particles are major problems, we would design another system for larger particles(like the dense phase conveying). But that would be done afterwards. We are determined to work with dilute phase conveying.
Thank you!! ■
Re: Pneumatic Conveying Design Queries!
Originally Posted by Amrit AgarwalDear Dinesh,
For this material a dense phase pneumatic conveying system will be more suitable. A dilute phase conveying system can be designed but it will not be practical.
I can design the dense phase system for you if you so wish.
Regards,
Amrit Agarwal
Pneumatic Conveying Consulting
email: polypcc@aol.com
Thank you sir for your concern. If we use dense phase pneumatic conveying, we require high pressure compressors, which isn't feasible in terms of our weight and economy requirements.
What if the maximum particle size we are conveying is less than 5 mm....
Can you please give me design guidelines for dilute phase conveying of such a system...
Thanks in advance!! ■
Re: Pneumatic Conveying Design Queries!
Dear dineshpanta,
To give more specific answers to your questions, it is necessary to have more specific information.
- Can you confirm that the system is a pressure system, fed by a rotary valve?
- A particle size distribution of the brick dust is required.
- Can the maximum particle size be limited to approx. 100 micron?
- What centrifugal blowers (volume and pressure at operating point, or full curve) are available?
A sketch of the intended installation would help
Have a nice day ■
Teus
Re: Pneumatic Conveying Design Queries!
Originally Posted by Teus TuinenburgTo give more specific answers to your questions, it is necessary to have more specific information.
- Can you confirm that the system is a pressure system, fed by a rotary valve?
- A particle size distribution of the brick dust is required.
- Can the maximum particle size be limited to approx. 100 micron?
- What centrifugal blowers (volume and pressure at operating point, or full curve) are available?
A sketch of the intended installation would help
Have a nice day
Thank you sir!
-It is a pressure system ,fed by a rotary valve.
-The particle size is around 90 microns on an average, but the maximum particle size may be upto 5mm(which are very less in quantity). Exact distribution isn't known.
-If we design a system for large particle size,it would work certainly for smaller size particles.We are trying to find upto what size of particles we can convey with the blower specs. that are available easily in our region.
-The centrifugal blowers that are available have a pressure of 0.1 bar guage(at max.) , cfm can be as high as required.
Have a nice day!! ■
Re: Pneumatic Conveying Design Queries!
Dear dineshpanta,
Using a centrifugal blower at an 6”pipe and an air volume of 0.38 m3/sec,
the indicated pressure is:
0.15 bar at 3 tph
0.108 bar at 2 tph
Whether this design is OK, depends very much on the fan curve.
A wrong curve might lead suddenly to a choked pipeline.
This calculation is an indication only
Take care ■
Teus
About The Pdf
Originally Posted by Amrit AgarwalDear Dinesh,
For this material a dense phase pneumatic conveying system will be more suitable. A dilute phase conveying system can be designed but it will not be practical.
I can design the dense phase system for you if you so wish.
Regards,
Amrit Agarwal
Pneumatic Conveying Consulting
email: polypcc@aol.com
Dear Amrit can you please email the pdf od yours i have already mailed you mentioning this
Thanks in Advance ■
About Pdf
Can anyone please email PDF of MR Agarwal or any pdf that has calculations for the design of the conveyor that will be very helpful for me.
Thanks in advance
kiran varghese ■
Pneumatic Conveying Design Queries!
Hello experts...Please help me with the blower design parameters(cfm and pressure) and pipe sizing for pneumatic conveying system according to my requirements. Following is a brief overview of my requirements:
Particle size:less than 20mm(brick dust and crushed brick particles)
Particle density: 2500kg/m3
Bulk density: 1062kg/m3
Conveying distance: horizontal:26m,vertical:4m
Material flow rate: 1.8-2 tons/hr
Thank you! ■