Posting this to see the variations in technique and SOPs when it comes to THCa crystallization. I have made diamonds with and without CRC. Interested in hearing from people who do and people who don’t. My process for NON CRC crystallization is as follows and will cover where temperature variations and strain has had a huge impact on speed of crystallization.
Pack your empty columns with dry ice or dry ice/ethanol to precool columns, then proceed with packing the columns with premium flower preferably (we only grow and process hydro). While you’re doing this you should have your Butane/Propane blend (70/30, 60/40) on dry ice for at minimum 30 minutes, a separate tank with just propane on dry ice also if possible. Let your columns sit packed with flower, sealed off, and with dry ice sleeves packed for at minimum 1 hour to freeze your flower. This can vary substantially depending on how big (wide) your columns are, the wider the circumference of the column the longer it takes to get those cryo temps to reach the center of your flower packed columns, adjust your chilling time accordingly. After this has been done we will proceed with CLS extraction. A dewaxing secondary column can help a lot achieving higher purity, but isn’t a must as long as you are running cold enough and have small enough micron filters in place. If possible use multiple filters and have your last filter be 1-2 microns in size (paper or weeve) . After she’s all together (column, collection pot, gas tanks, lines, recovery pump…etc) and we’ve achieved our temperature range, pull vacuum to assure we have no leaks and well begin cooling our columns even more. We start with “whetting” our flower with the propane only tank we’ve been cooling by pushing just enough solvent to lightly coat our bud. Propane has a much lower BP and will help our column get even colder as the recovery pump recovers the propane we lightly coated our flower with. Hydrocarbons produce a refrigeration effect when evaporating and more so under vacuum. To do this push propane until you barely start to see it drip into your collection pot or sight glass, then turn off the gas valve stopping the flow of propane and start recovering your gas via your hydrocarbon recovery pump for a good 15 minutes, the propane is now evaporating into you recovery tank, leaving behind ice cold temperatures from our refrigeration effect mentioned early. When finished recovering your propane, Next hook up your Butane/Propane blend tank which has been chilling on dry ice, restart recovery pump and start pushing your gas blend through your columns. We do not use soak times in sealed columns, we only allow the gas to run through our columns as fast as possible leaving minimal time to pick up unwanted impurities. You will need to run more gas then usual to get all the goodies since you are not allowing your flower to soak in your hydrocarbons, but just passes over and through your flower at high speeds. Some gas will still remain trapped in the columns, you can use N2 or a SMALL amount of warm propane to push the rest through into your collection pot, these methods will produce headspace pressure at the top of your columns forcing your wanted goodies and gases down to the collection pot . At this point you will continue with regular hydro carbon recovery until you have recovered around 97% of your gases. After you have done this, bring your collection pot over to your hooded ventilator to crack open your collection pot/plate and let gas evaporate until bubbling slows down. While that is happening you should be prepping your glass jars or miner. I put .5 grams of high quality shatter in each jar as this helps tell us when we are reaching our point of super saturation (will explain more). At this point you should have a thick syrup consistency extract ready for pouring into jars, use no more than 75% of jar volume as we need headspace to allow gas and terpenes to expand inside our jar. Pour your solution into the jars, which will start bubbling rapidly when it comes into contact with the shatter we added, pour very slowly. The shatter helps remove excess gas quicker, and tells us when the solution cant hold anymore THCa and is super saturated, if the shatter is disappearing and does completely that means there was excessive gas as it absorbed the shatter and isn’t quite ready to be seeded. Once the solution in your jars is just starting to stick when tipping jar back and fourth (very carefully) you should be ready to seed. Seeding is SUPER important and the quality of your seed is key to this whole process. If you don’t have diamonds on hand, I recommend going to a shop that sells high test diamonds and purchasing some. By high test I mean just large double facets that test out at 95% or better. if you seed with caviar consistency thca, you will most likely get caviar consistency. Ive had some jars need a seed to do anything and Ive had some jars grow double facets with no seed, but MOST of the time with MOST strains, the seed can make or break the size of our THCa diamonds and quality. Toss your seed or seeds if you have multiple, in the jar and lightly tighten your lid and allow to sit at room temperature. keep an eye on your jars as you are watching to assure the solution doesn’t absorb your seed into the solution. Bubbles should be coming from your seed even after light pressure has built up in the jar, this is your crystal starting to add to its size very slowly as long as saturation points were hit. Once you are sure your seed isn’t being absorbed into the solution tighten the lid all the way. Now a big variation I’ve seen is temperature needed to crystallize with different strains and this is partly due to the different molecular weights of the 200+ terpenes that exist in my opinion, they all having there own different molecular mass (weight). We’ve all been told terpenes are part of the crystallization process and they also gas off into the empty (air) portion of the jar along with your residual butane/propane. As these gas off into our jar head space, the content (%) of THCa very slowly increases allowing crystallization to occur, as the gas and terpene % decreases. As pressure increases in the jar, so does the BP of everything in the jar. To much pressure and nothing can gas off as the BP of your terps, cannabinoids, and gas gets to high. Just as a vacuum decreases BP’s of everything in a sealed vessel. I’ve had strains crystallize beautifully sitting at room temperature and ive had strains need to be on 105 f heat. Heat scares a lot of people when it comes to this process, but with our increased BPs due to PRESSURE were still all good and diamonds form wonderfully with minimal if any decarboxylation of any of our goodie’s. Example: If you put huge 2 gram THCa diamonds into a steel vessel under 1000 PSI pressure, you could let it sit on 150f heat and still not decarb it as the pressure increases the BP of EVERYTHING. So place your sealed jars on your heating pad or inside your vac oven at 85f and watch to see if tiny bubbles are slowly coming off your THCa seeds we added earlier. If not increase temp by 3 degrees every 30 mins until you see this start to happen. From there the jar will do the rest and slowly let off your gas and terpenes as jars are not made to seal under pressure, only under vacuum, so they will slowly leak for you. You can crack your jars to increase speed a few times in the first week, but also being sure to not let off to much gas as this will take away your pressure if you crack open to long. I personally only crack my jars one time after the first night and let the jars do the rest. The higher the temp the faster the jars leak. The process could be quick or take a month depending on purity and temperature. Ill be honest, in my experience CRC extraction does allow for a much faster crystallization time and lower temps and this is because there is next to no impurities (chlorophyll, fats, wax…etc) and this allows for rapid crystallization. But not everyone has access to CRC equipment so hopefully this helps some and curious to hear variations from other processors for NON CRC crystallization process’s and different SOP’s. Wrote this up fast, I will check it later as I get more time.