3 replies to this topic

[bosun]

Helllo,

 

I am currently studying hydraulics of packed tower. One thing that I am stuck at finding is minimum wetting rate. Can anyone help me how I can calculate the minimum wetting rate?

 

Thank you in advance

[breizh]

Consider this resource :

 

http://kolmetz.com/p...Rev 1.0 web.pdf

 

Breizh

[kkala]

Besides books on unit operations provide information, e.g. 'Unit Operations of Chemical Engineering" by McCabe, Smith, Harriott (McGraw-Hill), Chapter "Gas absorption".

As long as liquid flow rate is decreasing, minimum wetting rate is understood to occur just an interval before dewetting point (referred in the useful resource by breizh) and channeling (referred in mentioned book).

I also understand from this  resource  that operational capacity range of a packed tower (from turn down to maximum normal) should be from "loading point" to (a percentage of estimated) "flooding point". Minimum wetting rate is understood lower than loading point, but a general predicting correlation has not been found; only general recommendations to avoid channeling, like tower dia > 8×packing dia, liquid redistributors every 5-10 m of packing ( from McCabe; mentioned resource contains more and more precise recommendations).

Advice to improve above understandings would be welcomed.

Edited by kkala, 06 February 2013 - 05:07 AM.

[Michael_K]

Also "Packed Tower Design and Applications Random and Structured Packings" by R.F. Strigle Jr. and section 14-55 from Perry's Chemical Engineers' Handbook (8th ed) are worth to recommend for reading.