Reduce Air Consumption in Blow Tank

Posted in: , on 7. Sep. 2006 - 05:18

Dear all masters,

I have a job to optimize the blow tank (blow pot) operation, the focus is to reduce the air consumption..And I confuse, because pneumatic conveying is new thing for me..

Can someone give me advices about the methodology of this project, step by step?

I try to get some field actual data (such as air supply, blowing time, feeder time, pipe diameter etc) but we don't have any flowmeter or annubar to know the air flowrate for blow pot..

Should I install the flowmeter or annubar?bcause I want to know the air flowrate and I want compare to manual operation rate..

And if I get the DP by annubar I could calculate the flowrate in SCFM by use dieterich standard flow calculation.

Any advices, please??

Thanks & Regard

Bangun Prayogi ■

Conveying
Transport
Pneumatic Conveying
Solids Flow Measurement
Instrumentation
Process Control
Replies
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Re: Reduce Air Consumption In Blow Tank

Posted on 11. Sep. 2006 - 08:03

dear Mr Bangun,

If you know the blower data, you also know the air flow rate and you do not need an annubar.

success

teus ■

Teus

Re: Reduce Air Consumption In Blow Tank

Posted on 25. Sep. 2006 - 01:20

dear Mr Bangun

if you donnt want to use the flowmeter, so you could know the material you want to be transported, if you tell the material , some experts or professors using their experiments would like to tell some basis parameters avaliable that could be very useful.

sucess

■

Re: Reduce Air Consumption In Blow Tank

Posted on 26. Sep. 2006 - 01:15

OK, thanks for your reply...I will give some description:

1. The material is dust.

2. The operation of blow tank (4 ft3 blowpot) is controlled by PLC using sequence logic. The cycle time is Dust Filling 10 sec Blowing 40 sec Total 50 sec..The permissive interlock to operate this blow tank is the low level of the dust bin above blow tank, so if the level is OK, then the sequence will operate.

3. Capacity per hour 4.35 t/hr.

4. Phase density design 42.3 (Dense Phase System).

5. length line 261 ft.

6. air flow required 200 scfm

So, I think my chance is only reduce the blowing time (regardless total system modification)..And I need the blowing time formula, I mean the factors that could influence it.

I need the air supply flow actual data, so the annubar/flow meter is required...

Please advice..

Thanks a lot

best regards

Bangun

bangunprayogi@yahoo.com ■

Re: Reduce Air Consumption In Blow Tank

Posted on 26. Sep. 2006 - 10:02

You can control the air by using a pressure regulator and a chocked flow nozzle.

There is no formula to determine transfer times as such. Scaling from a test plant is normally

done to determine the max SLR for a given material. Then everything is calculated from there.

Transfer time are dependent on a number of things. But the most influence is of conveying pressure

and air velocity. Try reducing the air velocity and increasing the conveying pressure. There will be

a max. SLR and velocity limit for the dust, which you will have to find out. ■

Mantoo

Re: Reduce Air Consumption In Blow Tank

Posted on 2. Oct. 2006 - 01:09

Thanks for replying,

We have a pressure regulator but the problem is still appears.

Mantoo, i am interrest on your advices to reduce the air velocity and increase the conveying pressure...Could you please show me the way ?

Thanks a lot

bangunprayogi@yahoo.com ■

Re: Reduce Air Consumption In Blow Tank

Posted on 2. Oct. 2006 - 10:01

Pressure regulator alone doesn’t control the airflow; it is used with a chocked flow nozzle. If you install a choked flow nozzle then you can reduce the upstream pressure to reduce the air flow rate to adjust the velocities (I am sure you can do the sums). Make sure that your conveying pressure is at least 20% below the critical pressure of the chocked flow nozzle.

As far as increasing the conveying pressure is concerned there are different ways depending on your equipment / instrumentation. Since I don’t know your system I cant make a comment. ■

Mantoo