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[Boon Ping]

Hi everyone,

 

I'm currently assigned to design a packed tower to absorb a HCl exhaust gas stream saturated with water.

Some details are:

mol fac: HCl, air and water are 40%, 54.3% and 5.7% respectively

Inlet T: 60degC

Inlet P: 1.05bar

 

The scrubber is to be scrubbed by a 60degC water stream.

 

The gas flowrate is 335m3/hr.

 

My problems are:

When I wanted to decide the Lmin for this system, I don't know how to decide constant gas flow, Gs for this system. The air flowrate is constant but the HCl and water flowrate is changing along the tower! And how do I account for the evaporation loss of water?

 

For HCl equilibrium line at what temperature should I be using?

How do I decide the operating temperature of this absorber? By outlet temperature of the cooler?

Can I assume HCl is readily absorbed in water and all the mass transfer resistance lie on the gas side?

If I were to solve this design problem with manual mass and enthalpy balance, how do I approach it?

 

Please share your experience with us.

 

Boon

 

 

 

 

[S.R.Shah]

Boon Ping

This is gas controlled as it is easily soluble.Please refer Parry for coefficient
Please also refer Ludwig for cooled absorber design for
HCl gas absorption.

Cooled Absorber with recirculation of more quantity of water shall be suggested for varying gas rates

Please also check this web site for more data

SRShah

For varying flow rates cooled absorber with recirculation
Of absorbent shall be solution

Water temperature shall be at room temperature as it produces lot of heat

More ever please refer this website for more help