Pull down blanket. Good one. Buying now.
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Hereās what FM Global (heckin big insurance company) has to say about static electricity. Their data sheets are very helpful.
2.2 Occupancy
2.2.7 Solvent Extraction Plants
2.2.7.1 Apply Recommendations in Section 2.3.1, and bond together all tanks, vessels, motors, pipes, conduits, and building frames within the process.
2.3 Electrical
2.3.1 Bonding and Grounding
2.3.1.1 Bond and ground all conductive objects. This is frequently the least expensive method of preventing the accumulation of a static charge.
2.3.1.2 Make sure bond wires are mechanically strong. They need not have large current carrying ability,as the currents involved are minute. Uninsulated bonding and grounding conductors are preferred becausetheir condition is easily determined by a visual inspection.
2.3.1.3 The resistance of the ground connection should not exceed 10^6 ohms. Ground electrodes used for lighting or power circuits or for lightning protection are more than adequate for static grounding purposes. Other grounding methods such as connecting to a sprinkler system, electric conduit system, and the steel frame of a building also are acceptable.
2.3.1.4 Shafts, metal rollers, or similar moving parts on a machine should be grounded as illustrated in Figure 1.
2.3.1.5 All isolated metal parts of the equipment should be bonded and grounded.
2.3.1.6 Shafts that turn at high speeds should be bonded to the journal housing.
FMDS0508.pdf (207.3 KB)
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Honestly can we see pictures of the lab? If being in a band has taught me anything itās that bad grounds cause all manner of static, not just in the sound system. Ever heard of a āhot micā
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I had a talk with a friend who told me that I should remove anything plastic from the processā¦
Pouring etoh from plastic HPDE might also cause a static discharge ir juat wiping with a clothā¦
So staniless steel cans are supposedly better than any plastic.Dont know aboute tanes xanes but probably same theory appliesā¦
Thank you people for contributing to much disregarded safety issue that is extraction to this comunity!!
Best to all and stay safeā¦
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The triboelectric effect can be a bitch.
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Yup. tanes in plastic is a no-no. Which sucks because plastic is cheap and metal is not.
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depends which wires you connectā¦ 
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hey yāall.
Iāve got another example of essentially the same ignition event.
at pour out. with higher than normal back pressure. higher than normal propane, because over recovered and added back 70/30 (or 85/15?!?).
missing were static dissipative hoses.
tracking those down now.
everybody is a ok. training, and being prepared are important. as is servicing your fire suppression equipment. and playing in a safe location.
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@Photon_noir forwarded me this today.
With the headline
BREAKING NEWS!!!
MIT Students making BHO recognize the flow of inflammable non-polar solvent through PTFE hoses generates static electricity that could potentially spark a fireā¦ and their imaginations!
Figured this was a decent place to shareā¦ might even suggest that molsieves would work for the MIT trick if @CuriousFuriousā ignition is repeatableā¦
Edit: ā¦and no, they were NOT making BHO at the time. Still seems relevant to the discussionā¦
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:Are these pretty common in the industry? Iāve bought static dissipative products, but donāt really understand the concept here. If the system is properly bonded/grounded, then there shouldnāt be a charge to be dissipated, no?
Except for that last trip through the ptfe hose and into your jar or onto your parchmentā¦
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Sounds like we should be pouring into stainless vessels that are bonded/grounded
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If you imagine the problem is charge separation between the solvent and the ptfe liner on the hose, grounding the platter you pour to will make things better? Or worse?
Pretty sure the correct response is to dissipate that charge separation at the sourceā¦the ptfe hose.
Makes sense. In my head, as long as everything is bound and ground, thereās nowhere for an arc to occur. However, if the charge is in the solvent itself, I can see how it could arc right before hitting the theoretically ground pour vessel
I am sorry this happened to you, @CuriousFurious ! You are correct that the Drierite, especially when dry, can build static electricity in friction with dry hydrocarbon. This happens with friction between two dry insulating materials, such as butane and PTFE.
The effect is particularly hazardous when it occurs near an exit of the insulating fluid, most especially when that fluid is inflammable. This is why the exit (to air) spout of an inflammable liquid container must NEVER be filtered with ANY NON-CONDUCTIVE material!
I do not fully understand this system, but perhaps it could be of some use: Earth-RiteĀ® II Plus Ground Monitoring System - SafeRack
You probably already know this the hard way, but it bears repeatingā¦
ā¢ NEVER mount any friable (dust-creating through rubbing attrition) material or media above your collection vessel.
ā¢ NEVER try to support the weight of media with only a screen gasket.
And you should avoid the use of Drierite in your BHO system. Calcium sulfate can only absorb 2 water molecules of hydration, anyway. Although it is a strong desiccant, it has the least usable lifetime. Also, all desiccant salts stop working above about 29Ā°C.
Use 3Ć or at most 4Ć molecular sieve in a fully supported trap system, down(vapor)stream from your collection vessel. I can help you with a fairly simple unit design. Take care!
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@cyclopath In these situations (or potential situationsā¦ as in any collection tank with a pour spout), the spout, itself, as close to the end as is practical, should be tightly bonded to a grounding conductor to ground.
Also, any conductive pan onto which a pour is deposited should be alligator clipped to a grounding wire to ground before pouring begins.
If both are grounded, especially to the same ground, even in the case of terminal static electrical buildup (as in the Drierite case, above), the potential between the two conductive areas will be zero.
Alternatively, they may be conductively bonded to each other, but they still require both to be grounded for this arrangement to remain safe throughout their inter-disconnection procedure.
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Graywolf pointed out the anti static hose years ago but its expensive.
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Indeed. Not many folks seem to use them though.
Boss claimed swagelok didnāt carry themā¦I didnāt just look that shit up for yāall
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If you actually google that you come up with this:
and at the bottom it reads
" CSB also suggested additional safety measures for companies that handle such liquids:
- Obtain more detailed additional technical information on the liquids from manufacturers that may not be found on MSDSs.
- Purge storage tanks with an inert gas to remove oxygen.
- Add anti-static agents to the liquids.
- Pump liquids more slowly.
- Verify that storage tank level floats are effectively bonded. "
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