15 replies to this topic

[P4ul4]

Hi,

 

I would like to do the degasifier design to remove carbondioxide to reduce anion exchanger load.

Can anyone share with me the literature how to do the degasifier sizing?

 

Thanks in advance.

[fallah]

p4ul4,

 

As far as i know CO2 degasifying is mostly to be done by air stripping method. Googling will provide a lot of materials can help you out...

[P4ul4]

Hi Fallah,

 

Thanks for your reply.

 

To remove CO2, I will use blower and media.

 

I have tried googling to get info to do the design, however I couldn't get what I want. To do the design, I need to decide:

- location and size of water inlet and outlet nozzle; air inlet and outlet nozzle

- the distance between the point of water sprayed and the media

- what blower to be used

- the distance (height) between media and air inlet

- shape of the degasifier basin (circular or rectangular)

- etc

 

Please share if you have any info of it. Thanks.

[fallah]

P4ul4,

 

Most info you needed are detail design relevant. Anyway, as far as i know the blower is centrifugal type and circular basin included. The link below from a relevant company shows the main design parameters for an actual CO2 degasifier may help you out:

 

 

http://www.lantecp.c...ier_example.pdf

Edited by fallah, 11 April 2014 - 05:50 AM.

[P4ul4]

Dear Fallah,

 

Thanks for your quick reply and pdf file.

 

I got task to do detail design for degasifier system. 

For blower, I was suggested to use blower at 40 mmAQ. Is it a centrifugal type?

Please advise, since I am not familiar with this system design.

Thanks.

[fallah]

P4ul4,

 

The blower pressure depends on the packing bed elevation and packing characteristics but the air flow is normally considered almost 3 SCFM for each GPM of falling water in blower sizing.

Edited by fallah, 11 April 2014 - 05:49 AM.

[P4ul4]

Hi Fallah,

 

If I use pall ring media with 0.7m height.

I would like to know the ratio of air and water.

Is there any formula to calculate the ratio?

 

I have difficulty to decide the distance (height) between water inlet and bed ; and also the distance between air inlet and bed.

Do you have any literature about this? How do I make sure if water will distribute even for all bed's area?

Thanks. 

[Santoshp9]

Dear ,

Here is the design calculation sheet for degassier for your reference.

You will get all answers of questions you have through it.

 

Regards,

Santosh  CO2 Degassifier.xls   97KB   392 downloads

[breizh]

To support your query , I've attached document & link,

 

http://dardel.info/I...s/degasser.html

 

"The degasifier has three main components: the tower, the blower and the sump. The tower is filled with a large surface area packing that breaks up the falling column of water into a thin film and small drops. The blower forces a stream of air upflow through the water and out through the vent pipe. The sump receives the degasified water and stores it for a few minutes before it is pumped to the point of use."

 

It should help you out

 

Breizh

Edited by breizh, 14 April 2014 - 03:54 AM.

[P4ul4]

Dear Santosh, thanks for the excel file. however, i couldn't fully understand your example. can you please give me another example?

Dear Breizh, thanks for your explanation. i would like to ask you:
1. Should i design degasifier sump in circular shape area or square shape area? In my opinion, square shape is better so with the same volume, i need lower value in height. what is your opinion?
2. I found top manhole (at tower), side manhole (at sump) and overflow (at sump) are required. do you know the reason? if yes, please share.
3. Air flow value must be higher than water flow. is it correct the bigger ratio air/water, the better degasifier design?
Thanks in advance

[breizh]

Point 1 : I did a project where the design is really as described on the picture , material was FRP . The material for  construction should dictate the best choice ( SS steel , FRP, )

 

Point 2 : On tower manholes are necessary to introduce the packing and to remove them > 2 manholes , For the sump you also need a manhole for inspection and cleaning . You also need a overflow , in case of pump shut down (power outage is an example) , in normal operation level will quite high .

 

Point 3 : you need a good contact between air and water to remove the CO2 . ( refer to the PDF attached)

 

Breizh

Edited by breizh, 15 April 2014 - 10:30 AM.

[P4ul4]

Dear Breizh,

Point 1: so you used sump with circular shape area?
Point 2: as my understanding you have more than 2 manhole at tower. is it correct? and where did you place it? top and side?
Point 3: understood.
Thanks

[breizh]

P4UL4

 

Point 1 :Rectangular sump

Point 2 : Top : to get access to the sprays /distributor of liquid and introduce the packing ; Bottom : above the grid which is supporting  the packing

 

Hope this helps

 

Breizh

Edited by breizh, 15 April 2014 - 08:15 PM.

[P4ul4]

Dear Breizh,

 

Yes, it helps me a lot.

Please allow me to ask you more questions:

1. Why do you need to remove the packing? Will it break down or what? On my design, I will use pall ring from plastic. Can I assume no side manhole (tower; bottom) is needed?

2. What material did you use for grid? FRP?

3. Did you have level gauge in your degasifier sump?

Thank you.

[breizh]

P4UL4

After a while your packing will be dirty , broken , Delta P will increase meaning you will have to replace them .

For Operation manholes are mandatory .

Yes FRP / Plastic is  a good option .

 

Yes to protect the pump you need at least a LSL !  a simple gauge or tube should be sufficient for reading the level in the sump .

 

I cannot offer more .

 

Breizh

[P4ul4]

Dear Breizh,

 

Thank you for your quick reply.