Elimination of Sulfuric Acid Mist

[Fabcap]

I am in the process of designing a wet scrubber for the removal of sulfuric acid mist from exhaust air.

This mist is reported as having particle size of 5 - 6 micrometers and specific gravity slightly above 1, while the packing manufacturer has data only for 7 - 12 micron particles at that SPGR, and for SPGR 2 -4 at the particle size of interest.

Is there any equation to correlate removal efficiencies? Or rules of thumb to the same effect?

 

[Chance17]

H2SO4 mists are are amoung the hardest to mitigate.
I think you'll need fabric elements.
Hope you can stand the element pressure drop.

 

[Fabcap]

Yes, the scrubber will use a knit mesh mist eliminator above the liquid distributor.

 

[siretb]

A wet scrubber (alone, with no demister)can do about 2-4 microns d50 cut.

H2SO4 mist / aerosols should be much finer than that, so It's pretty sure that if the 5-6 microns you report is correct, it is not H2SO4 mist.

As said H2SO4 aerosols call for , a good mesh pad, and more effectives options would be ceramic candles / fabric (but you need to reheat if downstream a wet scrubber) or a wet electrostatic precipitator (WESP). A WESP is expensive, and ceramic filters mean pressure drop.

 

[Fabcap]

The mist is from battery formation lines, not sulfuric acid plant or the like. Particle size comes from the data I have been provided with.

I'm a bit rusty on the mist terminology: "d50 cut" means removal of 50% of the particles?

 

[siretb]

d50 means that a particule of that size has 50% chances of beeing collected, and 50% chances of escaping. So, yes 50% of the particules of the d50 size will be intercepted.

The particule distribution is a key element. If your mist is really 5-6 microns in size, a wet scrubber should get it by itself. A mesh pad too, and you will not need more sophisticated technolgies.