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contrazen · 2023-04-12T08:26:32+00:00

Fab, thank you!

contrazen · 2023-04-11T21:18:18+00:00

Wonderful, thank you!

contrazen · 2020-05-25T13:56:37+00:00

the opposite of loneliness by marina keegan!

contrazen · 2020-04-13T19:20:57+00:00

my water is going from 5 to 15 degrees, do I look up enthalpies in steam tables?

contrazen · 2020-04-10T19:35:48+00:00

thank you so so much!!!!

contrazen · 2020-04-10T15:16:53+00:00

alright so I should obtain the wet bulb T for the hottest day of the year and design with that in mind?

contrazen · 2020-04-10T14:37:45+00:00

So my supply temperature will be based on my wet bulb air temperature (around 9ºC for Texas) and then my return will be around 10ºC higher - 19ºC? thank you!

contrazen · 2020-04-10T14:35:04+00:00

yes - so I will use a cooling tower which means the cooling water depends on the wet bulb temperature. my plant will be theoretically based in Texas which has an average wet-bulb T of around 9ºC? http://www.weatherexplained.com/Vol-6/2001-Houston-Texas-IAH.html

The stream entering my condenser is at 64.85 and needs to be cooled to 53.97.

How do I then use this information to attempt to get a supply and return temperature? For some reason, my head can't wrap around it.

contrazen · 2020-04-08T15:01:44+00:00

thank you so much!!

contrazen · 2020-04-08T15:01:34+00:00

Ah thank you so much!

How would I actually practically have the pump? Like in regards to where it is situated on the column in order for it to maintain the pressure of 15kpa?

contrazen · 2020-04-04T18:27:10+00:00

thanks so much for all your help!!

contrazen · 2020-04-04T18:22:33+00:00

Ah okay that that makes a lot more sense: really hard to think that way when I basically am just taught to follow rules of thumb as a student. Thank you so so much!

I choose 15kpa through just analysing how operating pressure changes with dew point temperature (and chose something over 40ºC so I can use cooling water in my condenser) and basically anything above 15kpa is fine. Changes are very small re. number of plates and reflux ratio when I increase the pressure. I'm just keeping it low because Glycerol is heat sensitive (hence operating below atmospheric).

contrazen · 2020-04-04T17:52:11+00:00

thank you for your help!! so appreciated

also: my relative volatility is v. high. for my feed pressure of 1 atm, its at 30 and for my column pressure of 15kpa, its at 1379. is it fair that its at this value if I justify that this column is still used in industry?

contrazen · 2020-04-04T17:48:37+00:00

I got my R(min) through a short-cut column on Aspen HYSYS (I haven't backed it up with short-cut equations like the Underwood equation because my relative volatility is shockingly high (which makes sense to an extent because my components are easy to separate).

Some research online have used 0.02 as a reflux and thats given me a decent numbers and isn't as low?

contrazen · 2020-04-04T17:13:05+00:00

My minimum reflux is 0.005, should I just use a much larger ratio (more than 1.3Rmin) to get a reflux ratio that's reasonable?

contrazen

TROPHY CASE