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I'm looking for the standard requirement for setting up controls, vfds, switches and outlets near distilling equipment. Basically what needs to be explosion proof and what doesn't. Our electrical inspector is throwing a fit about controls and conduit running near our fermenters and mashtun, nowhere near our still.

From my understanding anything over 3 ft from the ground and outside a 6ft radius of the equipment isn't required to be explosion proof. Ideally it would be, but I'm looking for written regulation to bring to my inspector.

Any help is appreciated.

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Hey all,

The only definitive guide that will give you the real and actual answer is the "Recommended Fire Protection Practices for Distilled Spirits Beverage Facilities 3rd Edition", available from DISCUS for a small fee.

Anyone other than an engineer with a PE in Fire Protection, Mechanical / HVAC, or Electrical will not be able to give you answers enough to satisfy your Fire Marshall. And additionally, anyone offering you advice without those qualifications would be liable for any future damages or injuries incurred as a result of their advice.

The best reference is the DISCUS doc. Get it.

Cheers,

McKee

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Both Appleton and Killark publish guides to NEC Articles 500. It's a good guide to understanding the kinds of equipment you would see within classified areas, as well as what the commonly understood boundaries based on typical situations. Sometimes your local electrical contractor supply house will have the printed versions of these books on hand for free. Generally these will give you some good insight into the kinds of things your AHJ are insisting. The intent isn't to make you an expert, but to understand their position.

http://www.killark.com/literature/2011NEC.pdf

http://www.emersonindustrial.com/en-US/documentcenter/EGSElectricalGroup/brochures_flyers_pdf/nec-code-review-2014-appleton.pdf

Also critical is the NFPA 497, you can get free access here. If you haven't yet, take a look at the last 20-30 pages or so, you'll find them very helpful.

http://www.nfpa.org/codes-and-standards/document-information-pages?mode=code&code=497

Typically, the crux of the argument is what is considered a classified area, and for what reason, everything else is secondary.

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I always suggest that chillers or motors without proper wiring not be placed anywhere near possible spirit fumes. Partitioning off usually is a method used.

It's not just the distance of the equipment, it is where the fumes may possibly travel.

I know of an instance at a chemical plant that fumes traveled from an open door to their substation that resulted in an explosion and a death.

All of the above comments apply.

Mike

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The only definitive guide that will give you the real and actual answer is the "Recommended Fire Protection Practices for Distilled Spirits Beverage Facilities 3rd Edition", available from DISCUS for a small fee.

Anyone other than an engineer with a PE in Fire Protection, Mechanical / HVAC, or Electrical will not be able to give you answers enough to satisfy your Fire Marshall. And additionally, anyone offering you advice without those qualifications would be liable for any future damages or injuries incurred as a result of their advice.

The best reference is the DISCUS doc. Get it.

Which is exactly what I just went through. I already purchased it and was willing to share that information. Some people on here actually have been to law school are simply offering some basic help and direction without charge. You comments about liability are unfounded and ridiculous in this situation. Chill out.

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Lucidi,

The only time I'm not chill, is when the ADI Forums are used in the same way as homedistiller.org. This is a forum for professionals to share professional advice. If you aren't a PE in at least one of the areas I mentioned above, then you are not qualified to offer professional advice....especially on something so important, period.

The advice I was giving, which is the advice we all should be giving, is "seek out a professional opinion" especially in an area as important as the safety of your future distillery, its employees and your well being. The horrible accident at Silver Trail Distillery is your wake up call.

Humbly,

McKee

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"Humbly" McKee,

I have literally shopped out and priced well over 70 different explosion proof items/options for my distillery. I put in the work. I made my selections, based on what my PE recommended, and what was for the MAXIMUM amount of safety, not the foolish state/city minimums I happen to have here where I live. I own and have read the "Recommended Fire Protection Practices for Distilled Spirits Beverage Facilities", as obviously as my PE has. That being said, I have hundreds of hours invested into researching the equipment, availability and pricing. For example:

The lighting in my distillery is Dialite Safesite Wide-Lens Highbays. I was quoted pricing anywhere between $1,511.11 and $4,560.00 for the EXACT same products, from different vendors. The original poster is building a distillery, so that kind of information and the source in which he can buy it AT the best price, might be of some use to him, you think? Especially if it turns out he need 4 of them to achieve his desired luminous emittance. I'm pretty sure he would want to save that additional $12,000 or so for barrels maybe in that scenario. This is a forum to HELP each other. Plenty have helped me, and I intend on helping others.

And that is one of many examples...

Silver Trail is not a wakeup call to me. While it is unfortunate that people were hurt/killed, did you even look at that equipment they were using? It doesn't surprise me. It should be expected when you operate in a manner less than safely professional, you are going to suffer the consequences... eventually.

As for you previous comment, that I would be held liable for such advice, we can always test that. My advice to you is to pull that stick out of your butt and jump off a cliff. Then you can have your next of kin try and sue me because I recommended and advised it. Your call on the stick though... you can leave it in while you jump if you'd like.

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If the advice is only to "seek out professional opinion", why not just put that on every forum topic post and close the thread?

I appreciate the valuable assistance offered in many posts, that I believe is what this forum is for.

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Distilling is completely safe if YOU know what you are doing. Most the people "inspecting" writing codes such as 3ft off floor etc havent a clue about distilling. Flash arc will be an issue provided you have flammable vapor in the air. Having an emergency shut down, the knowledge to use ONLY the emergency shut down and the switch for the proper exhaust fan are things you should practice on a regular basis. As I posted in another post www.schnappstills.com is now making CERTAIN electric controllers, with explosion proof contactors that will shut the unit down. Nothing else other than the E switch and exhaust fan (located as far away as possible in the same room) and the switch preferably around the corner in another room) should be touched until the issue is cleared. Good luck and be safe. 

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On 7/1/2015 at 3:56 PM, John McKee said:

Lucidi,

The only time I'm not chill, is when the ADI Forums are used in the same way as homedistiller.org. This is a forum for professionals to share professional advice. If you aren't a PE in at least one of the areas I mentioned above, then you are not qualified to offer professional advice....especially on something so important, period.

The advice I was giving, which is the advice we all should be giving, is "seek out a professional opinion" especially in an area as important as the safety of your future distillery, its employees and your well being. The horrible accident at Silver Trail Distillery is your wake up call.

Humbly,

McKee

Just FYI if you read the report on Silver Trail you would see one thing in particular that does not make sense. The manufacturer of the still said it was rated at 8 psi I think it was. The still had a 150 psi WATER HEATER pressure relief valve!! The report did not say who installed the PR valve but I am guessing the distillery. Most small still guys will not install safety equipment to avoid the liability. 

A still should be an OPEN system and the pressure will not go above maybe 1/4 psi. It is necessary to have some pressure to move the vapor through but it will not go above 1/2 psi unless you have some blockage or something. You can get Apollo PR valves for 5 psi that are more than you will need unless you have a still made from tin foil. 

You have to remember that one psi spread over the surface of a 36 inch diameter still is about 1,000 lbs of actual force over that area! 

By the way the one thing the report does not clearly state is whether the injuries sustained were from fire or from hot water. Water at 200 degrees will cause severe burns as well. And the suspicious thing about the report is that the still blew out of the building. At 8 psi or even 10 or 20 psi it would most likely split open and not "blow up."

There are a lot of unanswered questions. 

Above all get a pressure gauge and relief valve with LOW psi. Very low.

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Heck, it could even be a propane tank from a forklift! I saw a building wall blown out from one.

Ethanol fumes can be really dangerous if they can move to a small area and concentrate. 

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GCD is correct, you should have a 5psi pressure relief valve on your inner boiler.  We go farther than that now and put one on top of all of our larger columns, as well as the inner boiler.  It is a very good idea to vent these pressure relief valves to the exterior of the building.  If anyone needs 5 psi pressure relief valves please click here https://shop.distillery-equipment.com/collections/parts-and-replacement-parts/Valves  We are Apollo dealers.  If you need help sizing pressure relief valves just give us a call 417-778-6100 or email paul@distillery-equipment.com.  Pressure relief valves must be sized according to the maximum volume of vapor that your still will produce.  A  1/2" pressure relief valve is not going to work for a 300 gallon still.  Also, it is a very good idea to have a vacuum relief valve on your stills inner boiler.  Some people have learned about the need for vacuum relief the hard way  We carry Apollo vacuum relief valves.  We also carry section VIII Apollo safety valves for steam jackets.

http://distillery-equipment.com

http://moonshine-still.co

 

 

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@Southernhighlander We might be hijacking this thread a bit...

Are you talking about using those relief valves on a steam supply or on the product side as well? I noticed that there are parts with B16 brass, which I believe contains up to 2% lead? Have you had any resistance from inspectors for using that on the product side, or is it not a problem since material is not routinely flowing through the valve?

 

 

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Lead is used in very tiny amounts on B16 as a cutting lubricant.  We pickle the contact area of the valves with a solution that removes the residual surface lead on all of the valves that go on our stills and mash tuns, but it's not really necessary.  The mash never flows through the valve and the contact area is very limited, so it is not a problem, even if we did not pickle them.     

 Of course there are residual welding chemicals left in the stills and the customer must fallow the instructions to remove those chemicals during the initial cleaning run.   This is a standard practice in the industry.  If the results of the cleaning run were tested there would be residual chemicals and minerals in abundance.  If there were any tiny traces of lead on the brass valves the cleaning run would remove it as well as the other nasties.  

Of course there are several nasties that you will have in your spirit including acetone and methanol.

I guarantee that no lead in any levels greater than normal would be found in the spirits produced by the hundreds of stills that I have in the field. 

      

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I was specifically referring to the pressure relief valve. The only risk I could foresee is if there was a drip path that allowed it to drain to the condensate collection.

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I was specifically referring to the relief valve in isolation, not to any particular still design. Meaning, if the valve was placed in a location where it could lead to condensate collection, I was wondering if it could be a problem.

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   If you pickle the area of the valve (only allow the solution to be on the brass) that will be in the contact with the vapor, with 2 parts white vinegar and 1 part hydrogen peroxide, by letting it sit in the solution for 5 minutes.  It will remove any residual lead.  If you did not pickle it, the first cleaning run would remove the residual lead.   If a cleaning run was not done, then the residual lead would be removed by the forshots/heads vapor of any run.  Keep in mind that the contact area of the vapor to the brass portion of the valve is tiny and the amount of lead there minuscule to begin with and that will be removed very quickly by the first ethanol vapor that comes through the vapor path because that vapor is a strong solvent

But to answer your question, because I always do whatever is safest, I would never put a b16 brass pressure relief valve or vacuum breaker at the apex of the vapor path, or in the downside of the vapor path on a still.  I have no reason to do that.  I would only put them in the upside of the vapor path  We put a 5 psi pressure relief valve on the top of the still pot and another near the top of the first column, just below the apex of the vapor path.

This discussion has caused me to decide to begin stocking stainless  pressure relief valves and vacuum breakers as well as some chrome ones .  Personally I like the look of the brass ones in contrast with the copper and stainless, but I think that most people probably like the look of the stainless better.

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Ok, I had looked at a few other sources for stainless ones, but I'll see what you find. Personally, I am comfortable with a brass valve, knowing that I can locate it properly. My bigger fear was whether an inspector would have a problem with it.

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If this is something that really bothers you, why not use a sanitary rupture disc for overpressure protection?

No moving parts, all compatible materials.

Simple metallic disc that is in a triclamp adapter.  Kettle on one side, exterior vent piping on the other.  No moving parts, very simple design.  Some companies even make rupture discs integrated with a triclamp gasket - that can be installed directly into a clamped pipeline junction.

Unfortunately, they are not inexpensive, and it's one time use.  However, if it bursts, it probably saved your a$$, and is worth every penny.

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I am considering that as an option as well. The cost per piece will be a big factor. I will not be using a conventional pot still or kettle. The design I am using will require about a dozen pressure relief points. My main reason for not using rupture disks is the one-time use. During software tuning, I could accidentally overpressure several times. It's not that I am seriously worried about my safety while doing this, the components are more than capable of handling the pressures, but I am planning to stay below 15 psig in operation to avoid ASME B31 compliance and let my building and plumbing inspectors rest easy.

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biodzlden

I don't think that any inspectors are going to have a problem with the brass valves.  We have stills in over 200 distilleries with the brass valves and no inspectors  have mentioned any problem with them..  

 Email me privately paul@distillery-equipment.com and I will get you a price for the stainless ones.  They can be a lot more expensive than the brass ones.

 There is another way.  You can run tubes into the bottom of a column of water.  Every 27.7" of water column gives you one psi.  If you run into a 56" column of water you will have a pressure relief device that is actuated when the internal pressure of the still reaches 2 psi.  The diameter of the water column does not matter so you could use a 2" diameter piece of pipe that is 83" tall and that will give you a relief device that operates at 3 psi.  If you need help calculate the diameter of the tubes needed to feed the water column pipe, just let me know the diameter and height of your continuous column and the amount of vapor going in and the amount of condensate that you will be producing per hr, and I can give you the size of the tubes that you need, if you decide to go that direction.

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That's a clever way to safely make a pressurized system. However, I will have pressures ranging from 7psia-15psia, depending on the part of the system so it probably isn't a great fit for my application. My water columns would be clumsily tall and I would run the risk of back siphoning during process upsets and startup conditions. 

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