Marijuana extraction technology has changed rapidly over the last few years thanks to a greater demand for concentrates and wide-spread decriminalization and legalization. The black, tarry “oils” that were once acceptable forms of “hash” have all but disappeared (apparently some poor fools are still smoking that toxic ‘Rick Simpson Oil’) and in particular, the development of closed-loop extraction technologies has represented a paradigm shift in the way both producers and consumers approach concentrates. At this point, closed-loop butane extraction is the best, most efficient method we have for extracting THC and when set up properly, it provides a scientific level of safety and control that can yield the highest quality products possible.
Closed-Loop Extraction is Safer
The most obvious advantage to a closed-loop extraction setup is that it provides a much greater degree of safety than “open blasting.” BHO extraction has gotten a bad rap over the last few years because plenty of stupid, inexperienced stoners try their hand at open BHO extraction and end up on the news because they blew themselves up. A closed-loop extraction is just that– it’s completely sealed off so that no butane can escape the system into the surrounding environment (thus avoiding filling the room with butane, though proper ventilation is always necessary, closed-loop or not).
Closed-Loop Extraction is More Efficient
Closed-loop systems will naturally be under greater pressure than open systems which, while not directly affecting solubility in any meaningful way, does increase the interface time between the raw marijuana and butane thus allowing for a more complete extraction.
Closed loop systems also allow for a more precise control of temperature which does have a direct effect on the solubility of THC into butane– though there are two ways of thinking about it. While an increase in temperature of the butane does allow for greater solubility of THC (and thus a more efficient extraction), it also increases the amount of water in the product (as water is just slightly soluble in butane), though thorough drying of the raw material and solvent could combat this.
Rather, many extraction artists choose to cool the extraction column to sub-zero temperatures which, while decreasing the solubility of butane, prevents many of the undesirable plant fats and waxes (and water) from making it into the solvent. This is a choice method since it avoids the need to “polish” or de-wax later using a cold ethanol wash. Closed-loop extraction systems also prevent butane from being needlessly evaporated and some systems even offer the ability to recover butane, allowing solvent to be used many more times without needing to be recharged.
Closed-Loop Extraction Yields The Highest Quality Product
The great Budweiser-endowed beer-scholar Charles Bamforth says with regards to taste in what is good, “to each her own,” but it’s hard to deny that the strongest, most flavorful, most cosmetically pleasant concentrates have been produced through closed-loop extraction. The only products that seem to come even close are the most carefully crafted, ultra-fine ice hashes which can hardly be seen as representative of an efficient extraction method.The use of these technologies is always accompanied by temperature-controlled vacuum purging which is the other half of the art & science of MMJ extraction. The vacuum purge is used to remove butane below the taste threshold of 3ppm, far below any level that could be considered dangerous to anyone.
While concentrates still have some legal-grey area, even in states where marijuana is legal, these advantages to closed-loop extraction are the reasons why the most forward-thinking states– states like Colorado– are creating regulations that will impose industry standards requiring closed-loop extraction for the safety of everyone.
If marijuana helps you and you live somewhere where it isn’t legal, you should move to Colorado (seriously!). Let’s stop open blasting once and for all, it’s just not very good.