Vent system design

[sgoel]

We have a equipment for filteration of solid from mother liquor. This equipment uses air to dry the cake after filetration cycle. This drying air is also routed out through filterate line going to downstream equipment. This results into splashing of liquid in the tank.

We would like to provide a vapor separator/ vent stack to the outlet line. We would like to know the typical design procedure used for such a system.

Thanking you in anticipation please.

SGoel

 

[jeap]

Dear sgoel:

From my knowledge you should have an additional line for venting the air in a convenient way. As you explained, drying is a different operation than filtering. This new line could have an automatic valve that opens when your system is in the drying process.

Considering that such a line may have some liquid and it would splash over around the vent you could install a knock out drum in order to separate this liquid from the venting air.

A KOD is a vessel that is designed in the basis of a air velocity low enough to separate liquid droplets, let's say 300 micron in size, from the air phase.

A lot of information in the literature has been published regarding design details of such a equipment.

I remmember that design equation is the classic Sauders-Brown and it looks like:

Vgas = K (dens(liq)- dens(gas))/dens(gas))^0.5

check:

http://www.eng-tips.com/viewthread.cfm?qid=10444

where Mr. Montemayor gives a good explanation.

More details on the design could be supplied for other members....