Hey guys so far not a good couple weeks lol
So we’ve tried for a second time today to run a 5L short path and we keep hitting problem after problem.
Our first run consisted of us going all the way to 230°C pulling out very DARK amber dist. You can’t even tell it’s amber unless you put a flashlight to it. It’s essentially cleaned up crude lol. Reason being (after much research this is my theory) we were using a pump that was way too small and had no vac guage. No problem. We’ll start fresh again with the right tools and everything will work out the second time right? Wrong.
We’ve been running our SPD for about 3.5 hours today. This is another first pass on some crude, not a second pass.
The biggest problem is the head temp won’t stabilize. It gets up as the mantle heats, but as soon as it reaches temp, it drops rapidly. We got all the way up to 220° on mantle, head temp jumped a little, but after a few min it dropped rapidly. Mantle to 225 and same thing. We’ve decided to stop for the day to try to get some answers and come back at this thing with a fresh perspective. We collected maybe 200ml of what we assume is heads. We were getting a good drip going as the head temp went up and finally stopped again at a mantle temp of 225° as we didn’t want to go higher and risk the crude.
I was noticing little air bubbles on the head/bf joint as well as the head thermometer joint. My guess is that it’s a vac leak. Is a vac leak the usual suspect when you’ve got head temps that keep dropping?
Here’s our set up
Here are clips of the little bubbles
Uploading: 2FD406B2-F02A-4624-BA12-83C3249EC789.MOV…
The lowest our vacuum would get to was 516, but blanked off, this vac gets down below 50 micron.
Any help would be greatly appreciated so my buddy and I can stop trying to kill each other via frustration
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Just realized the video of the bubbles on the joints won’t post. Working on getting it up on YouTube
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Not enough dry ice and or acetone/IPA-iso in cold trap? Fill it up to the mqx
Wrong type pump
No keck (sp) clamps at thermocoupler and head/bf joint
Nothing wrapping the bf to retain heat (not 100% needed, but sure helps)
Did you grease any joints?
What type?
What type of starting material?
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Ice has melted we kinda stopped filling it as it’s been off for about an hour
Wrong type pump? Can you explain? It’s a 12CFM 2 stage rotary vane Pump I was told should be fine?
We have about 40 feet of fire rope, but removed it to let everything cool so we can try to regrease the joints…
We use krytox grease. Greasing about 3/4 of the top part of the joint. Maybe we need to use more?
Material was mostly nugs. Maybe a year old but stored the entire year air sealed in 70° room.
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The pump ain’t nearly adequate. How high of a micron are you seeing during the run?
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It was jumping to 1000 when head temps would rise. But it did pull down to 500 when we started it up (mantle already heating) but blanked off we got it down below 50.
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You also have to ket the head warm up, so dont rush to a higher mantle temp just because you dont see anything happening. Probably have a vac leak, and that pump would if your real pump breaks and you can throw that on there just to finish a run. You should look on ebay for alcatel 2021i theres a bunch on there for a good price some even tested to 10 microns or less. Also with out knowing how you prepared your crude its hard to give a specific answer. Shine a flashlight from behind the glass and lokk for “smoke” and then try and find the source thats your vac leak
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Thanks for replying! So we did cold ethanol extraction, filtered it, stuck in the freezer for 24 hours, filtered again, let it come to room temp, carbon scrub with DE cake at bottom and a slow filter paper, then evaporated alcohol and decarb.
We let the temp sit for about 15-20 min before raising it more. After about 5 min every time of the head going up, it would sit for about 2-3 min at temp and then drop rapidly.
Pretty sure it’s vac leak cuz we saw bubbling on the tips of the head/bf joint…
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Ya rhe bubbles are a sure sign of a leak and sometimes your head temp until your in mains will go up and down its just all rhe different terp or whatever fracrions tour going through
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So did we not use enough grease maybe?
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Ok WTF so here’s another problem. Stir bar must’ve stopped functioning somewhere through the process. We can now pull the mantle out because it’s cooled enough (still at 100°C) and I couldn’t get the stirrer to make a reaction. Tilted flask to see the bottom and saw this char
Tried to use the mantle thermometer needle to feel around for the stir bar and realized it was stuck. We’re using a 64mm egg shaped on a 5L flask…
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Check your probe. Juat put any flask with some water in it and put you temp probe i side and set for a low temp and see how accurate it is. And then do the same with an empty flask with your stir bar to make sire both are working and how bigh rpm you can go. Im not sure what size mine are but they only fit through a #45 joint.
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Right. We definitely tried the stir bar in the mantle by itself and it can go full blast. Really curious what could hav caused this. @Demontrich you got any ideas on why It charred?
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Charred could be from scorching of the mantle and your crude. Could also be fines missed in the crude.
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Also just tested temp probe and it’s working well. Could star bar have got kicked off during, and then didn’t spin causing charring?
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In my experience its sugars and or chlorophyll. You said it was ethanol extracted. See if just plain water will clean the charred part. Ive ran etho crude and had the same,sometimes its even lil bit of plant material. But the flasks would not come clean with etho, a etone etc and then i tried just plain water and they were gonna in minutes
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Maybe but probably not unless theres a ton of char in there
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Will try that for sure. Honestly we bought this magnet for this run alone. And we drained flask, seems like magnet has lost its strength. Our magnetic wand can barely grab it now whereas before it was pulling it through thicker crude. How can that happen? Lol
Conclusion- quite sure the head fluctuations was due to vacuum leak. Could stirring also effect stability of head temp? Could be the combination of the two?
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Too high of heat will kill the magnets strength as your experiencing. Can even fully demagnetize it
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It wont let me upload a pic but check ebay for alcatel 2021i. I just founf one that pulls to 1 micron 600 free shipping. Irs a gamble but sometimes the people who have them for cheap got them from a real lab with monthly routine maintenance so a quick flush or two and you could have a brand new pump
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