Compare/contrast of pneumatic & mechanical conveyance for quicklime

rcbabcock - Maguire Group, USA
(not verified)
Posted in: , on 6. Aug. 2002 - 01:17

I'm looking for your thoughts on the relative merits of replacing an existing vacuum/pressure system in kind or with a new mechanical system. The current system conveys quicklime from storage silos 350 ft via vacuum and then an additional 150 ft via pressure. The system is old and needs replacement. I'm considering simple replacement of the existing components with new equipment and/or installation of a new silo closer to the point of use with a tubular chain drag conveyor to move the lime the 150 ft to the hoppers. Any ideas?

Re: Compare/Contrast Of Pneumatic & Mechanical Conveyance For Q…

Posted on 13. Aug. 2002 - 11:39

In my opinion you should still use pneumatic conveying systems. You will have less maintenance, less wear and tear, and easy operation.

Regards,

Amrit Agarwal (Tim)

Pneumatic Conveying Consultants

polypcc@aol.com

Bosentang
(not verified)

Pneumatic Vs. Mechanical

Posted on 16. Aug. 2002 - 03:08

I must agree with Amrit. Pneumatic systems are less costly to maintain. However, I would add that if you are making a change, then you should consider reducing the lenght of the vacuum system and increasing the lenght of the pressure system. You maybe able to reduce the energy consumption and size of the equipment.

We would be happy to look at differant pneumatic conveying configurations with you.

Re: Compare/Contrast Of Pneumatic & Mechanical Conveyance For Q…

Posted on 16. Aug. 2002 - 06:53

Dear Mr. Ayed,

You will need the following data:

Tons of material to be stored

Bulk density of the material

Particle Size

Angle of repose

We may need other data if mass flow bins are required.

Regards,

Amrit Agarwal (Tim)

Pneumatic Conveying Consultants

Re: Compare/Contrast Of Pneumatic & Mechanical Conveyance For Q…

Posted on 16. Aug. 2002 - 07:05

Dear Mr. Rcbabcock,

In my view a single conveying system would be better than a vacuum and a pressure type system. A single system will cost less and will be easier to run.

Most likely it will be a vacuum type system but I will need more data to give you a firm recommendation

Regards,

Amrit Agarwal (Tim)

Pneumatic Conveying Consultants

polypcc@aol.com

Bosentang
(not verified)

Re: Compare/Contrast Of Pneumatic & Mechanical Conveyance For Q…

Posted on 16. Aug. 2002 - 07:38

Again I would have to agree with Amrit that a single system should be more cost effective. However, I think that a pressure system would be a less expensive option.

I used: 50 lbs/ft^3 bulk density

500 ft Horizontal run

167 lbs/min rate

Using this I calculate that a vacuum system would requrie a 5" line running at about 9.5 In Hg with 1200 CFM with a large blower with 30 BHP.

A pressure system could use a 4" line running at about 6.5 PSIG with 630 CFM with a much smaller blower with 21.5 BHP.

Also, remember the less air flow the smaller your receiver filters and bin vents will be.

Of course, this is based on the information above. I would need to know more about your exact project before giving you an accurate comparison.

Re: Compare/Contrast Of Pneumatic & Mechanical Conveyance For Q…

Posted on 21. Aug. 2002 - 04:00

In my opinion you should retain your dilute phase system and try to re-use your conveying blower to minimize your cost.

Dense phase (or low velocity) systems are used if particle attrition is a problem.

Regards,

Amrit Agarwal(Tim)

polypcc@aol.com,

or pccsolids@aol.com