7 replies to this topic

[Rajesh Patel]

Hi

I have an action to determine capacity of existing scrubber used to scrub pure (100%) HCL gas.

How to apply NTU = LN ( Ybottom/ Ytop ) equation for 100% HCL gas input and 2ppm HCL concentration in outlet?

Can you recommend equation for HTU also for same condition?

Thanks

Rajesh Patel

[breizh]

Rajesh,

Consider this resource.

Hope this helps

 

Breizh

[Art Montemayor]

Pierre:

 

What happened to your handsome photo?  It was much better than the present one.

[breizh]

Art ,

I tried to upload  a "fresh one" and failed !

Have a good day .

Pierre

[Art Montemayor]

Pierre:

Ah!  That's a lot better.

I thought for a moment that some viral attack had taken place on our member's photos.

 

Thanks.

[Rajesh Patel]

In ref of my question as above:

 

Inlet is pure HCL gas and density is 1.4 kg/m3.

 

Outlet should not increase HCL concentration more than 2PPM.

Can I take following value of Ybottom and Ytop?

Ybottom = 1400 gm/m3

Ytop = 2PPM = 0.00.2982 gm/m3 (Converted PPM into gm/m3)

[Rajesh Patel]

Please note, Ytop =  0.002982 gm/m3

[siretb]

Hi

You want to scrub pure HCl?  When you say you want 2ppm at top, does this imply that that the rest is water vapor and some inerts (not present in the feed of pure HCl) to be scrubbed.

I think that 2ppm is not much, I would rather consider 5 but this is your specification

 

Scrubbing HCl with water will have a large heat (enthalpy) effect, and shortcut designs (like the ones involving HTU-NTU) are not safe when you deal with concentrated solutions, which seems the case.

You should calculate the first stages using rigorous methods (you need to make a choice on how concentrated you want the acid to be at bottom, that will yield the liquid rate, and the temperature.

for the final stages (top) the HTU will be packing dependant    Count HTU between 0.2 and 0.4 meters.

 

keep in mind hot HCl is highly corrosive