amount of dust created when milling

[Crooked Arrow]

I'm working with an architect on building plans for a 1 BBL brewery and the local municipality has expressed concern about milling grain on site. They are asking how much dust will be generated is there any kind of industry standard that I can reference? I'm not really sure what to tell them.

[spetrovits]

I don't know if anyone has quantified the amount of dust created by the crushing process. Most of what I found was related to actual milling, that is, making flour, which is clearly not useful for brewers. I did find this thread, though>

https://discussions.probrewer.com/sh...-and-City-Hall

Maybe something in there will help. Good luck!

Edit: I noticed that the links in that thread are broken. The pic of crushed grain I can't help with, no idea where you could find another one (wink smiley not working), but the NC-OSHA document referred to is at http://cdm16062.contentdm.oclc.org/c...oll22/id/79893

[Jer]

This is an ongoing piss-off with inspectors and municipalities.

Where I live there are breweries (50HL) that mill in a “room” made of poly curtains, one that mills in a sea can on the owner’s driveway,, and they wanted me to build a 24’ tall, 12’x 12’ concrete block “chimney” to direct the blast skyward... I declined that suggestion.

I’ve looked and looked and looked, and could not find any data for a brewery mill. I did find the details of what is required to have a plant explosion - particle size, % in the air, etc - and a brewery mill could run uncleaned for decades before it’d even be close. My architect and I are actually planning on doing a journal article (with some test data using sieves) on this topic to try and put an end to the shit-show that this is.

After all my reading, I think that a few hours with a sheet-metal-smith to make an enclosure, and a basic grounded wood shop vac should be more than enough, and reasonable, and affordable, but hey, who am I??

JR

[GlacierBrewing]

I'm working with an architect on building plans for a 1 BBL brewery and the local municipality has expressed concern about milling grain on site. They are asking how much dust will be generated is there any kind of industry standard that I can reference? I'm not really sure what to tell them.

Hi Crooked Arrow,
When we were building out, our local/state governments required us to mill in an “explosion-proof” room: external light switch, sealed light housing, industrial external venting with make-up air, 2x6 walls. This was all due to the threat of a grain dust explosion.
Now when I actually grind in, I see little dust in the air, however, if I take my mask off I do smell it and feel it a little in my throat so it is present. I suggest you find the next closest municipality with a small brewery and find out their requirements and present that to your powers that be.

Prost!
Dave

[Jer]

Hi Crooked Arrow,
When we were building out, our local/state governments required us to mill in an “explosion-proof” room: external light switch, sealed light housing, industrial external venting with make-up air, 2x6 walls. This was all due to the threat of a grain dust explosion.
Now when I actually grind in, I see little dust in the air, however, if I take my mask off I do smell it and feel it a little in my throat so it is present. I suggest you find the next closest municipality with a small brewery and find out their requirements and present that to your powers that be.

Prost!
Dave

What makes up your external venting and make up air Dave??

JR

[Larry Horwitz]

don't call it a mill...call it a grain cracker. (which it is) Save yourself a pile of headaches.

[Jer]

don't call it a mill...call it a grain cracker. (which it is) Save yourself a pile of headaches.

Did that. Someone tipped them off.

JR

[GlacierBrewing]

What makes up your external venting and make up air Dave??

JR

JR,
I have an industrial, wall mounted, ducted, ventilation fan (similar to this: https://www.mcmaster.com/ventilation-fans). This fan sucks out the dust-laden air from the room and deposits it outside of the building. I have, also, an appropriately sized make-up air duct coming into the room bringing in fresh air. The fan is wired with the light so it all turns on at once. We had to make certain the fan was specifically suited to remove grain dust; e.g. adequate air movement, sealed electrical connections.
Grain dust explosions are no joke not to mention all the nasties that will grown in accumulated grain dust in your mill room.
Prost!
Dave

[Jer]

That makes sense. So a basic draw out for the floating particles, and a sweep of the floor once a week. Fan with explosion proof motor, wiring, switches.

I agree that dust shouldn’t be ignored, but some jurisdictions are completely bloody out to lunch re: the reality of what a “cracking room” in a small to medium brewery entails.

JR

[lhall]

I'm working with an architect on building plans for a 1 BBL brewery and the local municipality has expressed concern about milling grain on site. They are asking how much dust will be generated is there any kind of industry standard that I can reference? I'm not really sure what to tell them.

https://discussions.probrewer.com/sh...dust+collector

Build you one of these. It will keep the dust down and save your sinuses.

[Jer]

That’s exactly what I was thinking. Makes perfect sense to me. Not sure if it’d make “enough” sense to the local inspectors.

JR

[Junkyard]

Our inspectors and fire Dept. didn't really even realize what was going on in our mill room (our mill wasn't set up when they came) they came back for some other stuff and our mill room was very dusty on the floor so they started saying that was unacceptable and they might require an explosion wall. Luckily we had our grist case designed to be totally sealed up, with a stainless pipe connecting the bottom of our mill to our grist case. So we sealed everything up and then attached a duct and a dust collector to pull positive pressure on the grist case while we are milling. There is almost no dust now and zero percent chance of any explosions. We invited them back to inspect the mill room upgrades and they were very satisfied. I've heard some people report their counties, states being much more unnecessarily tough on breweries in the mill dept. However so it's best to check with your surrounding breweries like others have stated