Design of Mixers 2

[Mandy]

Hello all,

Can any body point out methods utilized for the design of industrial mixers, basically for mixing liquids in a vessel.

How is it done in the field, are the designs optimized for power consumption, impeller sizes etc.

Does anybody know of any software for this type of design?

Thanks in advance,
Mandeep

 

[butelja]

Get your hands on a copy of the book FLUID MIXING TECHNOLOGY, by Oldshue, James Y.

Publisher: New York: McGraw-Hill, 1983
ISBN:0-07-047685-3.

This is the definitive reference for what you are after.

 

[MJCronin]

Mandy,

Contact Chemineer and ask about the technical papers that they offer (These are old reprints from "Chemical Engineering" magazine) Although ancient, they are well written and offer all that the beginner needs to know about mixer design and specification. The old standard... Perry's chemical engineers handbook has mixer information.

http://www.chemineer.com

A Chemineer competitor that will offer a manual is the "Lightnin" company ( I know.... it sounds like a moonshine distributor from Kentucky......) These people are very knowledgeable and take a lot of peride in thier products.

http://www.lightnin-mixers.com

The Sharpe mixer company offers software to size and to establish horsepower requirements....It is an EXCEL spreadheet that is useful to size simple one speed designs.

http://www.sharpemixers.com

Mixers are not typically sized in the field (unless of course that there was no project planning..... everything is being done at the last minute, and your boss has an MBa....)

Large industrial mixers are typically designed and selected based on the chemical process or processes expected to be used in production. I have sized several mixers for "paint production plants".

I have found out that the biggest difficulty is to get the production staff to decide upon all of the various paint combinations( percent solids, viscosity, density, temperature, mix times etc) that the mixermight see. This becomes especially difficult when the process may change in the future, or some new product is developed.


Hope that this helps !!!


MJC

 

[Mandy]

Thanks MJCronin and butelja for the information.

These sites also had a preliminary mixer sizing form.

MJCronin, in the design of mixers, the same agitation level can be obtained from diff. combinations - with/without baffles, number of impellers, center or out-of-center shaft etc. How to determine the optimum combination to reduce cost and power consumption. Is it some thing learnt by experience or are there guidelines available.

I will check the other reference material mentioned in the earlier posts.

Thanks,
Mandy

 

[MJCronin]

Mandy, (are you female ???)

Deep within the bowels of most process-oriented chemical companies, in a dark, smelly office near the boiler in the basement, there lives a semi-recluse mixer designer. The purpose of this old "troll-like" creature is to answer the occasional question about reactor and mixer designs

Upstairs, where the dancing young MBAs count their bonuses and celebrate quarterly profits.... a technical question is sometimes asked.... about mixer design.....a question much like yours...

The troll winces, scratches his balding head and responds.... sometimes.....and goes back to his lair....

Anyway.... the answer to your question, Mandy is that mixer design is, at a certain point, more art than science. Most mixer designs are not optomized for the process and the process at many plants repeatedly is changed....

Find that troll within your organization and ask him your questions......if he hasen't died or retired.....


MJC

 

[Mandy]

MJCronin, no I am not a female. ha ha...

I guess their r more females with the name Mandy.

thx for the information.