2 replies to this topic

[mana.hdn]

Hello Everyone

I have been assigned to design a deaerator

It is needed to deaerate a water entering at a rate of 35 m3/hr at temperature of 25 C so when it leaves the deaerator with oxygen content of 8 ppb

I have read a lot of books, searched for design criteria, asked friends or professors no one had a clue or could not give me any reference or method to calculate or design it.

I tried to use the common distillation tower design criterias (trying to design the tower and packings or trays needed then size the vacuum pumps and air ejectors to produce a high vacuum) since it has to be done in 25C the absolute pressure should be 0.4543 psia (so water can boil and release O2 or CO2 or any other gas dissolved in it) the gas density is very low around 0.02 kg/m3 (infered from Aspen plus flash2 calculation) and it will give me very high rates for flood velocity like 80000 m/s and because of that i will have a very small cross sectional area for the tower.

can anyone help me how to calculate and design this? Is there any reference, design criteria or something to help me with it? how can i calculate the amount of packing or trays needed? 

the data I have are as below

water incoming rate 35 m3/hr

tower should work at vacuum and 25C

outlet specification is 8 ppb O2 

electrical conductivity (which I don't know why is it needed) 0.0002 micro s/cm

TDS 10 mg/lit

Chloride 6 ppm

calcium 0.1 ppm

magnesium 0.3 ppm

sodium 3 ppm

viscosity in and out 0.89 cP

outlet pressure 1.7 barg

hold up time at sump 5 mintues

I truly would be grateful if you help me

 

[Profe]

Hi Mana.hdn

 

First of all why do you need deareator?

 

For boiler feed water conditioning, try the next links:

 

http://www.spiraxsar...nditioning.aspx

 

or: http://www.gewater.c...h_10_boiler.jsp

 

I think that will be useful

 

Good luck

 

Fausto.

Edited by Profe, 20 October 2015 - 08:53 AM.

[mana.hdn]

Thank you profe

I read the two sites you sent the links

I have read like 20 or more articles like that, see it is all like theoretical approach none has been practical design approach

If you have any information toward that i would be grateful

and yes the deaerator is for producing boiler feed water but has to be under vacuum and done at 25 centigrade degree

Edited by mana.hdn, 21 October 2015 - 05:30 AM.