Ok understood. I’ll pull out the standard tomorrow and see exactly what’s allowable. If it requires normalization maybe we can add normalized results on a second page (or issue a supplement as you recommended). If we are required to list normalized results, I think I would prefer to keep it the same document though but with the “un-normalized” data front and center since that’s what y’all are wanting to see at a glance.
Thanks for your input!
Awesome that you are willing to listen to us!! Super appreciate it
I think we’re all lucky to be part of a community where this conversation can even take place. We’re smarter together than any one of us is individually 
.
I have more coming on sulfurs, single phase liquid sampling, olefins, remediation measures. With everyone’s help we can sort all this out so y’all have the products you deserve.
I personally think if you did this. Every other company that didn’t follow suit is gonna lose market share to you……
Oh we’re doing it.
Whatever standard y’all help us come up with we will be adhering to. And that goes beyond the testing and data presentation pieces.
I just think the more data. The more the consumer has to make an informed decision. I’ve talked to so many gas companies over the last few days. Some mad at me. Some enjoying this conversation and some genuinely trying to better themselves.
I’m just kinda dumbfounded no one really noticed all the 100% coas till I mentioned it. I was like how is everyone’s gas perfect but I’m always finding lubricants in my collections in the past. Weird.
I wish you and your team a lotta success. And that goes for all the gas people here. I have deceit relationship with most if not all the gas people and wish everyone the best!
Definitely more data. But we can go beyond that. What olefin hydrocarbons do we not want to see in our products? What sulfur limitations? Do we need a standardized single phase sampling method? How should our tests be run and the data quantified and presented?
There’s A LOT to sort through and nail down here. I know my posts are long (and getting longer lol) but I’m trying to end each one with a proposal to include as part of a centralized “forum standard” for these solvents. And that’s where we need to put collective our heads together.
Dumb guy in the room.
I buy gas with .1% unknowns. I use a whole tank and add another one in. I now have ~.2% unknowns in my tank minus whatever is left in the product. This keeps adding up and up and up.
I may not notice a difference on my first second or third run. It might even take me 100 runs. At some point it’s going to leave more and more unknowns in the product which would cause an issue.
As an extractor we need to know the how much is in there, how much is acceptable, and do a complete purge of the system every x tanks to clear the unknowns.
Am I wrong in thinking maybe this isn’t just a bad gas issue but an issue of people scaling and using more and more butane and the unknowns adding up into levels higher than we’ve seen?
Even this solution sounds fine. If you want to show what percentage is unknown in any clear way that’s exactly what I’m looking for! Can you get THC to do this for me?
I’m sure that’s an issue. I’m not familiar enough with extraction SOP’s to give you any guidance as to cleaning procedures and intervals but there are plenty here who are. And at the new gas standard with greater levels of transparency, maybe that possibility is reduced? Or at the very least you’ll have the information you need to make a more informed decision about the potential buildup in your system.
For you? Anything. I can’t speak for THC but I can pull the right strings for customers I’ve set them up with.
We’ll work up a few sample formats over the next few days and see what y’all think is the most useful. Once we finalize I’ll call your rep and let him know what you need.
Thats a valid point, assuming its not from a new tank, my operating tank is rarely empty. Only when cleaning it but then running multiple new tanks into it over time. Potentially compounding whatever might be in there.
Come to think of it I’ve never met anyone (myself included) that ever cleaned there operating tank
I do it every couple months just to make sure no moisture and give the transferred gas another trip through the sieves.
Let’s talk about sampling for analyses.
Headspace analysis for water is definitely pretty straight forward, the hardest part is collecting the vapor phase without releasing it to the atmosphere. Drilling a hole in a mason jar then quickly putting in a gas syringe is usually the best practice but that type of sample testing is definitely not ideal for anything other than water.
I sincerely hope no suppliers in the extraction space are producing COA’s via vapor phase headspace sampling. But I don’t know that they aren’t. Another great reason for standardized practices. As @SidViscous mentioned above, such a sampling method would not result in a thorough analysis as it is not representative of the composition of the tank as a whole, especially when looking for heavier hydrocarbons.
However, ensuring single, liquid phase sample introduction is difficult and, as such, may not be a regular practice. To properly pull a single, liquid phase sample we have found it necessary to apply a 1,000 psi helium pad on the constant volume sample cylinder. The current requirement is only 200 psi above the sample pressure but, as soon you open the cylinder to analyze, that pressure starts to fall. The massive pressure pad allows us to avoid any bubble point issues which would produce lower recovery results. Even then, you’re still always limited by the sample collection itself, slow and steady is always best especially with such light hydrocarbons that would rather “flash” into the cylinder. The helium pad definitely helps squeeze all those hydrocarbons into one homogenous single phase sample.
Additionally, any sample drawn is only as good as the sample cylinder being used also. There is an “industry standard” sample cylinder available that, if we so decide, I can link into our ultimate sampling SOP.
Given this, can we safely assume that our standard should include testing only via single, liquid phase samples taken via an SOP that mirrors the above steps?
We do complete cleans and fresh solvent once a month. We make sure we are at the end of our batch of solvent, then empty our tanks, clean them with water and soap followed by lab grade acetone. They then are ready for fresh distilled solvent to enter. Just got a new system with one large solvent tank so this will make this process a bit easier as its on wheels an one tank vs 4. Im sure there are lots of companies not taking the time to clean their solvent tanks nor using fresh solvent. Im a firm believer that there is carry over from runs when going at scale from time to time and so its needed to have some procedure in place to mitigate any contaminations.
You can actually do headspace effectively even looking for heavier compounds as long as your curve is generated using the same/similar matrix. IE if you use gc headspace grade butane and add the impurity standards to that, you can accurately quantify c6+. It will obviously not pick up the mystery oils though as they are nonvolatile. This method should be used to quantify water anyways because it is substantially less volatile than the light alkanes
I went to a gas tank filling training class in Denver provided by general air… what you have there is more than likely soot from the inside of the tank. From what was explained to us, the way they clean out gas tanks is by torching the inside of the tanks to eliminate any trace gases and anything else that might have built up inside of the tank. Not too sure how often it’s done, but it definitely comes through on majority of tank fills that we do. I started using the same setup I would for any other run as far as my filters go. I pass the gas through the usual 5 micron screens, followed by a one micron paper, on top of a one micron sintered disc. The collection vessel is always clean after that during tank fills.
Learn something new every day!
So would the best practice to be to analyze the liquid phase sample to pick up any potential nonvolatiles then if there is any indication of moisture look to headspace sampling to pin down?
Yikes to that cleaning method.