Okay, here we go
I’m pretty new to extraction, have emptied my collection base half a dozen times or so. On every run, I seem to be averaging around 5% yield across the board. From different strains, different combinations of trim/lowers/nug, dry vs FF (after compensating for 70% water weight) my average yield seem to always land around 5% +/- 1%. The quality varies of course. Just ran FF nug for the first time and got some wet consistency badder that I’m quite proud of, however, with these yields,I must be doing something wrong here. I’m certainly open to hiring a consultant on this, just thought I’d test my luck with an open conversation first. Anyhow, here’s my set up
I currently have a 5lb top fill bvv professional apollo. I swapped the solvent tank out for a 50lb SS non-jacketed tank, and run 100% nbutane. All of my hoses are jic, injection hoses are insulated. I inject through a 28" 1/4 condensing coil, then through a 1/4" mt69 coil before filling the top of my 4x24" open jacket column. I recover with 1/2" lines, through a 4x24" sieve with 13x beads, then into a 1/2" 50’ coil before going back to the tank
Material prep procedure:
For dry trim/lowers, I don’t manipulate the material before filling my column. I pack down each handful with a packing rod and rubber mallet. For FF, the material is cut off the plant, weighed, vacsealed, and thrown in a cooler with dry ice until I receive it. Before packing that, I smash the nugs in the bag with a rubber mallet, then load/pack each handful
Once pressure testing, distilation, and cleaning is complete, I begin the process by leaving my solvent tank on dry ice for an hour or two (something I don’t find necessary for following runs because the solvent gets cooled during the recovery process). As the tank sits on dry ice, I fill each condensing coil bucket with a dry ice/denatured alcohol slurry, adding enough dry ice in each until it stops boiling off, and gets below what my -40 infrared thermometer can read. I then mount my packed tubes, vac down the whole system, and add dry ice slurry to the column jacket, letting that sit for 20-30min or so.
When I’m ready to run, I load the headspace on my tank with 50psi of nitrogen and keep the tap open. I then crack the injection valve, push until I see solvent in my collection, then close the valve the separates the column from collection and soak for a minute or so before dumping. I repeat this until I hit at least a 4:1 solvent ratio. When it comes time to switch columns, I recently started running n2 through the spent column to push all the solvent I can into the collection. When I feel i got the majority of it, I circulate hot water through the spent column jacket and recover everything I can before dismounting the tube, and doing it over again with the next.
I like to keep my recovery water temp around 100 degrees or so. When I get down towards the bottom of the extract, I let it get a little colder, around 80 or so. With the butane recovered, I remove the splatter platter and pour either on parchment or in pyrex and begin post processing. There’s usually a gram, maybe two that gets left in the platter.
Possible causes for 5% yield:
Moisture in solvent- During my first run, I ran live material that was quite wet, not FF. It was cut off a plant, and thrown in a freezer. It thawed and unthawed a couple of times, and was, to reiterate, quite wet. I was young, naive, and had no idea what a molecular sieve was either. I never dumped that solvent tank after, but it has been refilled enough times that the original solvent from that run is rather dilluted at this point. It has also been through my oversized sieve quite a few times since
Material prep- I don’t grind or breakup my dry material, however I’ve never run dry nug, just dry lowers and trim. I’m more concerned about my FF prep, and that I may be taking too long from cooler to column, and the material is dragging in moisture from the air.
Solvent ratio- is 4:1 (dry material) a pretty optimistic number for someone in my situation? My tank holds 24lbs, and if I can I run all of it. Sometimes if I feel it wasn’t enough, I’ll recovery some, then push it again
Soak time- I’m pretty aware the cost/benefit of soak times are contentious, but if anyone would like to lend an opinion on my soak method please feel free.
To those who’ve gotten this far through this post-- I really appreciate it. I’ve been scratching my head for quite a while on these returns, and would love to hear another opinion. Thank you.
Photo caveats: the brass fittings on top of my material column are temporary. I was in a pinch after discovering leaky threads on a SS tee. I know the mole sieve should be vertically mounted, and have made racking mount this system my winter project. Not in the frame is my 20" allegro explosion proof fan/ducting