That is basically the same conclusion I've come to as well. After running 2 25lb tanks at 1800psi (~3 hours each), the end result was a only a few grams of golden goo. The taste was rich and dabbed smooth, but would've been able to produce a couple ounces of BHO for the cost in CO2 that was used.
TBH, instead of tinkering with it more, I'm going to sell or repurpose the unit and go back to butane.
Here are a couple pictures of what came out. After a few days, most of the excess water dried out and the waxier chunks became more translucent.
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Yeah, what I've found as well. SCFE CO2 extraction is more expensive than hydrocarbon extraction, and while it can produce a good product, I have yet to see a superior product.
Some of the research with compound extractions and co solvents may turn that around but a persons actions are usually a direction reflection of their perspective and you will note that though I have experimented with and could be designing and building CO2 systems, I continue to experiment with more elaborate hydrocarbon systems.
If and when we get the Apeks's lab unit offered to us pro bono for trials, we will pick up where we left off with JYN's SCFE CO2 scuba tank system.
To test my theories, requires a greater fluid exchange rate than you can achieve in a passive system like either the scuba or the Joe Blow, so I need a system with pumps.
Sort of like the difference between a passive and active butane CLS.