I have been training as a synthetic organic chemistry for the past four years. We have always had a static gun in the lab near the scales to prevent the loss of precious starting materials. They are cheap and get the job done.
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He means all metal enclosed equipment (extractor, pumps, fans, chillers) should be bonded to your ground ring. Much like a clean room in semiconductor manufacturing, you should wear anti static shoes as well.
Deffinatly No wool or polyester garment
I have a ground wire to almost al equipment being cls or not
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It is very important to fully understand what is meant by grounding a piece of gear. If you start adding grounded component chassis wires going to ground then with shielded components the shielding itself can become a ground loop that will drive sensitive electronics crazy.
Generally speaking the system must be bonded from component to component or you have a floating ground which in some cases is necessary but not for this discussion. All good designs deal with this internally with the third wire in a grounded cord which is green. This wire is often tied to the same point as the white nuetral wire (typically system ground on single phase gear) on a standard three wire plug. This makes it possible also to detect ground fault errors by the systems watch dog circuits.
What happens if you add a third wire between components is that you now have a path for current flow in a loop. It connects both chassis on two components and each of those metal chassis is also connected to ground through the third wire. Somif you trace the wires you can see that a loop is formed by the conductors. This might work fine for years however when that ground loop is hit with electrostatic emmisions that cross part of the ground loop then that wire acts like a conductor inside a generator and an unwanted voltage can easily down very spendy equipment acting goofy. Mucho billions over the years since we uncorked electricity have been soent chasing down ground faults.
My point is that prior to adding a bonding wire it really takes fairly intimate electronis info to understand how a ground loop works and how to avoid them. My experience from many years as a control systems engineer taught me how finnicky this stuff is to wire around. Some internal circuits are meant to be a floating ground inside the cabinet somadding a simple bonding wire can defeat this scheme and you mat or may not ve able to tell. If you have a good meter you can test for youself and only then if a problem with floating ground exists would anyone normally want to add anything to mitigate electrstatic discharge.
Standard practice upon appriaching a bench is to touch the metal bench to discharge the static. Or touch your dogs nose to see if you have static build up… mans best friend. 
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I was speaking mainly to racking and extractors thet could develop a potential difference. At the local flavor extractors Kelsec, all large vessels and stainless equipment are bonded, same at pfeizer.
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that would explain the lack of static electrickery that I have experienced in OR, at least moist of the time 
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very punny…lolz
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Edit: mats outside room walking in.
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Yeah, I asked my buddy real quick. Discharge outside of room). We have flex seal rubber for walls inside the room we’re building. Just got the 12” 863cfm c1d1 fan, and wiring that up tomorrow. Then plexi for lights to be sealed off… all in the far back of the container
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Grounding is something I’d have expected to be a feature on any big extractor.
When hydrocarbons pass through tubing they can create static which can then explode.
@MagisterChemist I’m curious if your membrane skids that recover heptane are grounded?
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I agree. On mine, I put grounding on all columns and racks, number 14 wire, then number 6 green wire from the whole set up to a panel outside the room.
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I got a shock from the critter I’m currently bringing online…just a couple of days ago.
200psi air rushing out of the pour spout not only cooled the pour spout below freezing, it ripped a respectable number of electrons from their former homes.
Ive received larger shocks, but this was the first solid nip I’ve gotten from an extractor (excluding the 600V AC the fuge I’m sitting in delivered…) in seven years of playing this game.
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Yes, they are. It’s not exactly a hard thing to include though — you should be able to do it yourself on any extractor that doesn’t already haveit.
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That’s scary. Knowing it is possible is one thing…but when possibility becomes reality…
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This event was scarier.
Included ignition.
I was working the problem with @CuriousFurious via text when he solved it.
He’s agreed to share what happened in greater detail shortly.
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Here’s 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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Seen an explosion from liquid alkanes entering a vacuum pump.
The lab I was visiting had 1 vacuum pump with a T leading to their vacuum oven AND evacuating their CLS post extraction.
Well…one day they forgot to close the evac line and flooded the system.
When I noticed the vacuum pump spitting hazy clouds of liquid I pointed it out and went to close the evac valve. The other guy went to turn off the vac pump…big mistake…soon as he touched it a fireball erupted in his face
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