Dust mitigation

We have a serious dust issue in our shop. From welding, grinding, laser cutting, powder coating, and sand blasting we have too much dust circulating around. When sunlight shines inside you see it, and if you leave a cup of water out it's undrinkable the next day. We always have to wash or wipe down customer's parts regardless of how long they have sat before pickup.

We have decent ventilation in the welding booths, we have moved sandblasting into an outdoor booth, have the correct dust collector for our laser, etc. The powder coating booth uses MERV 12 furnace filters and is pretty bad, but it's on the other side of the shop and is far from the only source of dust. The oven is unventilated and smokes a fair bit every time a batch of parts is baked.

Aside from getting better powder booth ventilation and putting a vent hood over the oven, what else should we do? The laser dust collector works well but does allow some dust out during blowoff. It's a similar story for everything else. Works okay but not okay enough.

We are considering getting or making some air cleaners using hepa filters or powder coating type filters. Does anyone do anything similar and how is it working for you?

This is a 27000 square foot fabrication shop. Welders and sandblasters have supplied air respirators, and our powder coater has an adequate respirator as well. But other operators do not, and dust accumulation on electrical panels and machinery is a significant maintenance concern.

While we will be improving our point of use filtration, I don't think it's possible to catch everything.

What do you think the investment into a low dust shop would be and how much power do you think it would consume?

You could have the dust analyzed, and work from there.

I would think an electrostatic precip would be better.

Jesus, dust, tell me about it. Dust is our punishment for trying to reshape God's earth.

That's an interesting thought, getting it analyzed.

I completely forgot electrostatic precipitators were a thing, even though that's what I search when buying high voltage power supplies.


Anybody have recommendations on businesses to talk to? Or is it as simple as a high voltage electrode in a tube? I haven't looked all that much into them other than seeing they aren't readily available.

Strostkovy said:

That's an interesting thought, getting it analyzed.

I completely forgot electrostatic precipitators were a thing, even though that's what I search when buying high voltage power supplies.


Anybody have recommendations on businesses to talk to? Or is it as simple as a high voltage electrode in a tube? I haven't looked all that much into them other than seeing they aren't readily available.

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No I don't have any, I would buy a ready made unit.
I recall seeing a very old unit (had rectifier tubes) that had water & drain plumbed to it, it would wash itself.

You may want to talk to a HVAC engineer, but you won't like what he tells you. You can go all the way to clean room environment, but the cost would be great. More exhaust with an equal or greater amount of makeup air would be a start. See what they do in auto painting, drug making, computer chip manufacturing.

If you have multiple independent dust collection systems the airflow in the building is likely to be confused where the different air streams interact. Most of the dust will go where it should but around the edges it could be swept all over the place and hang in the air until it finds somewhere to settle.

Needs someone with appropriate experience to look at the whole building and sort out the airflow. Unlikely to be cheap and may need shop re-arrangement.

Possibly something as simple as some of those transparent hanging strips, just brush through, door/partition things in strategic places may make a difference.

Clive

I dont know about codes etc, ive experience in car body extraction.
How difficult would it be to separate 'clean and dirty' ops? Could be as simple as having the dirty side extracted, and drawing air though the clean side.


What Clive said about competing airflow is a good point, you could compartmentalize real dirty ops and input separately from outside.

My feeling is that the biggest mistake made in filtration systems is the distance between intake and exhaust. If you hang one of those units from the ceiling it pulls the dusty air in from one side and exhausts clean air out the other. So some of that clean air gets pulled around and right back in, and the air in the corner of the room doesn't get touched. My wife does crafting in a 12' x 40' (the top room of my 1 1/2 story shop) which generates very fine wood dust. I have an intake at one end of the room, ducting in the trusses to lead to the filtration unit and then ducting to get the clean air back to the other end of the room. So there is a constant flow of filtered air going from one end to the other and the air stays very clean.

If you want to speak with someone I would start here: Oneida Air Systems - The Industry Leader in Dust Collection | Oneida Air Systems

Steve

Your shop is significantly larger than my garage but I recently just put in a cheap Wen recirc filter type system during a fairly large fan/welding project that made me realize I was not being healthy and wanted to at least get started in the right direction quickly and easily. I am amazed how much improvement this unit makes in general cleanliness in the air while doing welding/grinding. The outer filter went from white to definitely not white very quickly.

I’d recommend something dedicated for the oven and then just a few of these simple cheap recirc units around the shop at grinding areas or other places that seem to collect dust as a starting point.

So everything except for the welding booths is filtered and returned. Powder coating filters are inadequate but powder only makes a fraction of the dust.

We do have a divided shop with swamp coolers on the clean side that can pressurize the entire building, but draw a lot of power. They help with the dust on one side of the shop, but not the other.

We also have the nuisance that powder coating is a real dirty application but is sensitive to dust, so airflow from other dust sources across powder is a problem.

We are revamping our powder coating next to include an oversized booth and a vented oven, and have already prevented sand and sand dust from entering the shop.

Strostkovy said:

I completely forgot electrostatic precipitators were a thing, even though that's what I search when buying high voltage power supplies.

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I have a Honeywell electrostatic unit in my 4000 sq ft shop. It was marketed to body shops etc. I purchased it when we were doing metalspraying and fabrication, still use it now for coolant mist. A search doesn't bring the same unit up now, perhaps it's discontinued, but there are other similar units, such as the smokeaters you saw in all the bars before smoking indoors was banned.
Aercology makes air filtration equipment, I bought 4 used units cheap intending to attach one or more to machines, you do see used collectors on the used market, could be just pick up a few and try something temporary to see what works?

Mud said:

I have a Honeywell electrostatic unit in my 4000 sq ft shop. It was marketed to body shops etc. I purchased it when we were doing metalspraying and fabrication, still use it now for coolant mist. A search doesn't bring the same unit up now, perhaps it's discontinued, but there are other similar units, such as the smokeaters you saw in all the bars before smoking indoors was banned.
Aercology makes air filtration equipment, I bought 4 used units cheap intending to attach one or more to machines, you do see used collectors on the used market, could be just pick up a few and try something temporary to see what works?

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How much did you pay for it and what square footage did it claim?

Strostkovy said:

How much did you pay for it and what square footage did it claim?

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No idea on either, was so long ago. It's about a 30"-36" cube, sucks air in the bottom and exhausts out all 4 sides at the top. I looked for it online and can't find it, so would assume it's no longer available, but searching for bodyshop dust solutions might turn up something similar.