6 replies to this topic

[conan_kaya]

Can i know what is a turndown ratio for a distillation column?

[fallah]

Can i know what is a turndown ratio for a distillation column?

Minimum controllable feed flowrate / Maximum controllable feed flowrate

[Padmakar Katre]

Can i know what is a turndown ratio for a distillation column?

Dear,
For any system the turn-down ratio is called as ratio of minimum flow to maximum flow which it can handle.

[latexman]

The turndown ratio I'm familiar with is always > 1, so it's maximum controllable feed flowrate / minimum controllable feed flowrate. The keyword is controllable.

[Padmakar Katre]

The turndown ratio I'm familiar with is always > 1, so it's maximum controllable feed flowrate / minimum controllable feed flowrate. The keyword is controllable.

I hope the word Turn-Down itself is evident to say its value is less than 1. Normal terminology in design is
Normal Flow = 100%
Degin Flow = 100% + Degin Margin e.g. 10% = 110%
Turn-down = e.g. 60%.
I hope it will be helpful.

[latexman]

I hope the word Turn-Down itself is evident to say its value is less than 1.

Sorry, but logic and the English language sometimes do not coincide. Maybe, it's a regional thing, so all I can speak to is the common practice in the U.S. chemical industry where the turndown ratio is > 1. Specifically, it would be written as, for example, 10:1, and spoken as "10 to 1". Take a look here:

http://en.wikipedia..../Turndown_ratio

Hope this helps.

[Padmakar Katre]

Sorry, but logic and the English language sometimes do not coincide. Maybe, it's a regional thing, so all I can speak to is the common practice in the U.S. chemical industry where the turndown ratio is > 1. Specifically, it would be written as, for example, 10:1, and spoken as "10 to 1". Take a look here:

http://en.wikipedia..../Turndown_ratio

Hope this helps.

Dear Latexman,
Thanks for this and yes thats true. I checked it on my side its always more than or minimum equals 1. Sorry I hope you don't mind for my argument. Have a nice time.