WolfeXtracts
9m
This is meant to serve as kind of a general starting point for nitrogen backfilling vacuum ovens.
Get yourself a two stage nitrogen regulator, something that can regulate down to a single LB in resolution preferably. You’ll want to be between 0-15 PSI for the vast majority of use.
I like these:
https://www.micromatic.com/primary-nitrogen/low-pressure-series-nitrogen-primary-double-gauge-0-15-psi-gauge-842n-15
Hook up your regulator to your nitrogen tank (I prefer the UHP or ‘ultra high purity’ stuff for the negligible increase in cost its worth it in my opinion) Affix appropriate plumbing to your hosing situation and run a hose from your nitrogen tanks regulator to the vacuum inlet on your vac oven and voila, you’re hooked up. Remember to never build pressure in your oven, only using nitrogen to SWEEP through it.
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Do not pull vac.
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Warm your ENTIRE slab of hash oil to whatever the internal temperature of your oven is set to. I’m generally between 94-101 F for 100% butane hash oil. Check all four corners and then center with a non contact thermometer ensuring the temp of the slab is uniform. This can take up to an hour. Cannot stress the importance of this step, patience will be rewarded.
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Pull initial vacuum.
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As you see your slab start to react and 'Muffin" begin letting in the nitrogen to counteract the swelling of your hash oil.
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Repeat this process until the slabs bubbles become much more uniform in size. Just like decarb the initial pull will have all sizes of bubbles off-gassing, as they evap the bubbles will become more uniform.
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Close off nitrogen, keep vacuum running constantly. Be wary of a secondary muffin slowly creepin’
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Be sure to pay close attention to how the slabs react during sweep and after closing off nitrogen until you get a feel for those reactions.
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From here out every time you ever break vacuum the vacuum should be neutralized with nitrogen.
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Repeat the slab heating and sweeping process every time you flip or break vacuum.
Hope this helps.
Anyone who can amend or improve any part of this please feel free to add!
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Good info but it can be done with out nitrogen by just bleeding in o2, just make use to put a filter of some sort over you vacuum release so to not pull anything in.
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True, it’s just that O2 tends to corrupt pretty much everything it comes into contact with, oxidation and whatnot. I’ve seen definite color differences in doing a side by side 4 day purge at 90 degrees with N backfilling vs O2. Also if you simply vent with atmosphere you’ll be pulling in all the relative humidity your surrounding environment holds. Both water and oxygen are the enemies of good hash. I believe this inert backfilling process was invented for silicone and semiconductor curing back in the 60-70s could be wrong there though.
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Fully agreed n2 is the way I just saying it could be done
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Funny thing is I haven’t seen much degration once a stable extract is exposed to air for a few days
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How much reduction in purge time have you seen using this method? We are currently running a 6-7 day purge to get our shatter slabs under 100ppm. I’ve used various techniques when it comes to temperatures and vac pull, but the 6-7 day marker has been the most consistent. Just adds one more reason to the list of reasons i don’t like shatter. Will this method also help when it comes to purging the HTE after it has been separated from THCa crystalline?
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For every form of sugar, shatter, wax or batter I’ve never had to exceed 48 hours to achieve 0ppm residual solvent analysis.
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I haven’t played with it when it comes to hcfse and htfse but in theory I would say, yes, it should reduce times for removing solvent. Though with the supersaturation of the solvent being so crucial to forming crystals this quicker Evap may not work in your favor and will almost certainly create smaller crystals.
Thank you very much for the knowledge man! How often are you flipping when you use this technique? We’re currently flipping every 18-24hrs depending on when the slab is poured off.
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Happy to help, dude. I flip every 10-12 hours. 14 hours at the most.
You’re the man! I’ll implement this process and shoot you an update asap! 48hrs to 0ppm sounds like a dream.
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Let me know if you run into any hiccups! Happy to help you dial it in.
http://www.slickvacseal.com/slickvacseal_com_10262015_032.htm
One of these attached to hosing on the vent port.
That’s what I did. I also use one on my diaphragm pump when I use the compressor side when filtering etoh thru my columns
Do you know if these fit on the back of the 3.2cf AI vacuum ovens?
I use one attached to a silicone hose for my 0.9 AI Accutemp. Judging by the pic every AI oven is the same on the back so it should work as long as you have it attached to hosing (as a female adaptor).
https://aivacovens.com/vacuum-ovens/accutemp-32/
Excellent, thank you very much for the tip!
I’m always on a 72 hour schedule, with a flip every 12-14 hours w/no nitrogen. Does the nitrogen help sublimate the slab causing an easier purge?
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Sweeping nitrogen, especially on the initial purge allows you to lightly agitate the surface of the slab with an inert gas, this not only will prevent muffins which gives you greater usable oven space but it also increases the surface area exposed on the initial vacuum substantially. This greater surface area exposure leads to quicker and more uniform off-gassing. At least that’s my understanding. Nitrogen and argon also dramatically reduce oxidation of terpenes and cannabinoids during purge.
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@WolfeXtracts what pressure do your set your regulator to when you sweep?
Really appreciate the sop! Purchased the regulator you recommended as well 
. Do you use this in a cascade? Do I need anything else or any other tips?
