Looking for alternatives to a baghouse for removing airborne starch 1

[GACOSUChE]

I have 6 mixing vessels of varying sizes and types for formulating adhesives in batches and the main powdered ingredient is corn starch. Currently, the bags are simply dumped in at the top of the mixer and a dust plume of starch is created, which is a situation that needs to be changed. We have an unused baghouse there (which was originally bought for a different facility by a company we bought), but the manufacturer's rep has told me that because of the deflagration index (Kst) of corn starch that we could not retrofit it for this use. Are there any alternatives we could consider for dust collection?

 

[PeterAB]

Hi GACOSUChe,
Your safest bet is a wet scrubber. I work for TurboSonic and we have installations treating particulate from corn milling. I never post my email address to prevent spammers from picking it up, but please check us out at

http://www.turbosonic.com

Peter.

 

[saxon]

GACOSUChe, I take it your using std. 50-80 paper bags, manually added to the process. Have you looked at the possibility of installing a bulk bagging system or pneumatic conveying system with storage silos tieing these sytems into an automatic dispensing control scheme? As your original baghouse manu'f. has pointed out, corn starch has a relatively wide explosibility range and a high deflagration-detonation pressure rise requiring special attention be paid to pressure and flash release and or suppresion in the equipment design.

If dusting is still a problem, you may want to take a look at cyclones or cyclones attached to baghouses. Once again, special attention must be paid to deflagration-detonation control/release.

Hope this helps.
saxon

 

[GACOSUChE]

Saxon,

You are correct in your assumption that we are manually adding 50 pound bags of corn starch. The problem with pneumatic conveying is the prohibitive costs involved with installing such a system. This particular starch is only used in one product, and while we would stand to gain a significant break in price by buying in bulk instead of bags, those savings wouldn't justify such a capital expenditure. I guess what I would like to know is if installing said baghouse would increase the likelihood of a "dust bomb" occurence.

 

[phoward]

Eliminate the source and the bag house question is moot.

Seek a closed system to empty the bags, let the dust settle before you open the door/hatch for the next bag.

Also, in a closed container, use the solvent for the adhesive as a side wall wash down to speed up the cycle time to open the hatch for the next bag.

Load all the bags for a batch inside a bag charging house, close/seal it up, remotely open the bags, and leave closed until process completed.

 

[saxon]

GACOSUChe, I'm not familiar with the existing bag house and whether or not blast panels and the like have been installed in the equipment for the service intended. You're Manu'f. nixed that idea.

As for the possibilities of a dust explosion. I've always been of the mind that if you're handling flammable or potentially explosive materials, sometime in the future you will either have a fire or explosion and the design and operations have to take this inevitability into account.

If you can't affored the capital investment in a closed distribution system, the next best thing would be the installation of capture hoods, and a dust collection system that has the proper deflagration/detonation equipment installed.

Good Luck.
saxon