Why the Eden Labs FX2, 20 liter, 5,000 psi supercritical co2 extractor is the best choice on the market for botanical extraction

Eden Labs has been manufacturing supercritical co2 extractors since 1997. Co2 extractors were far less sophisticated in those days. Nobody built systems that recycled and recovered co2. The gas just fed in from co2 storage cylinders, through the extractor, and then vented out the building. Pumps, valves and gauges were not designed for the pressure and temperature swings that co2 extraction subjected them to so maintaining them was problematic.

The industry has come a long way since then. This article will cover the history of how the co2 extractors that Eden Labs, and its competitors made, changed and evolved in the intervening years and will make the case for why Eden Labs is the best choice today.

In 2007 I became determined to solve the problem of co2 recovery. It was just too costly and inefficient to constantly vent off gas and keep running to the gas vendor for more co2.

In my research, I ran across a type of pump called a gas booster which is designed for the sole purpose of pumping a compressed, pressurized gas to a higher pressure. The co2 coming out of the separator where co2 and extract separates was around 350 psi and the extractor vessel operated at 800 psi and upwards so it seemed like a perfect solution.

The early experiments went smoothly and the new design was launched the same year. This was before cannabis legalization so all the sales were for botanicals such as vanilla, kava kava and algaes due to the algae biodiesel boom which worked well with the new design.

Once the cannabis market came online, we started to notice two problems: the extractions were taking too long and the gas booster pumps were breaking too often. It turns out that cannabinoids dissolve more slowly in co2 than a lot of other compounds. Cannabis also contains a lot of mono terpenes which were entraining in the co2 vapor and going through the pump where they were carbonizing into grit and ripping up the pump cylinder.

It was clear to me we needed to figure out a new method that utilized pumping liquid instead of gas. The advantages to this were obvious. Co2 in liquid form would be much more dense so each piston stroke of a pump would be moving a much larger volume of co2 thus reducing the overall extraction time. We chilled the co2 as well making it much more dense. The mono terpenes in cannabis and other herbs would no longer be a problem because they would be dissolved in liquid where they would remain stable and not affect the pump.

There were challenges and disadvantages however. In a liquid system, the co2 is still leaving the extract separator in vapor form. Before it can be pumped, it has to be rapidly cooled and compressed back to liquid. This required the addition of chillers, cooling towers, and accumulators.

After much experimentation, the Eden Labs Hi-Flo line of extractors was launched at the end of 2012. These extractors were much faster than the old design and were pretty much maintenance free if used correctly. To this day, the original Hi-Flo units are part of our line of extractors. We also have the FX2 line which are double the speed of the Hi-Flo.

Getting back to advantages and disadvantages between gas booster vs. liquid pump extractors, there are only advantages for the end user of the liquid extractor. It’s faster, quieter, uses less power, and suffers far less maintenance issues than a gas booster extractor. The disadvantages fall only on the manufacturer. The liquid system has 4 pressure vessels, the cooling tower, a powerful recirculating chiller and dual heating systems whereas a gas booster unit has only 2 pressure vessels, one heater and a small chiller.

This means that an extractor manufacturer can build a gas booster extractor for half the price and have it done in half the time. For this reason, and this reason alone, gas booster extractors have flooded the cannabis market to the detriment of the entire industry.

In an odd twist of fate, I have been hired as an expert witness in three different lawsuits against three different manufacturers of gas booster co2 extractors. The problems are all the same: pumps constantly breaking, vessel closures failing due to cost cutting on pressure vessel standards, and automation failures that exacerbate the other problems due to false readouts.

The automation problems are an interesting side effect of the mindset of these manufacturers. They can build an extractor for half the price of a properly designed liquid unit, add a low budget automation package and still sell it for less than a manually operated liquid extractor. The sales pitch is, “why would you pay all that money for a manually operated extractor when you can get this fully automated beauty for less?”

Although Eden Labs offers automation as an upgrade, we know from experience that automation does not make an extraction faster, easier or more efficient in any way except for data logging which is important to larger institutions and R&D projects. Experienced extraction professionals always choose a manual system knowing it will be more reliable and offer more flexibility in extraction parameters other than the 3 or 4 programs that are the only options in a typical automated extractor.

Getting back to the original intent of this article, there’s more than just pumping liquid that makes the Eden Labs FX2, 20 liter, 5,000 the best choice for an extraction facility. Let’s start with the extractor vessel. With a 5,000 psi rating it allows for faster extractions under a wider range of conditions than a typical 2,000 psi system. This is important if you have a variety of herbs you are working with. Eden Labs can also offer a co-solvent pumping system for working with other organic solvents and compressed gases such as ethanol, methanol, water, propane, and R134a extractions.

The most amazing thing about the extractor vessel is it uses the most reliable closure on the market. Utilizing a Teflon coated metal seal that is squeezed into place by four large bolts that connect the two flanges, this seal will never fail. Anyone who has worked with a co2 extractor is probably familiar with the misery of having a seal blow in the middle of an extraction. Co2 fills your facility forcing everyone out of the building, the whole system has to be opened up and repaired, time and money is lost.

In recent years, many fast acting, toolless closure designs have hit the market. We tried them all. When they work, they’re wonderful. Simply lower the cap into place, give it a ¼ turn twist and you’re sealed up. Problem is they are all prone to frequent seal failures. The reason for this is they use a hard Teflon seal which is easily scratched when the cap is twisted to seal the vessel. The scratch turns into a crack when co2 pressure is applied and failure occurs.

Next in line as we move left to right across the extractor, we have the most accurate and reliable regulator valve on the market. This high precision, metering needle valve holds the extractor vessel pressure right where you want it and never clogs.

The dimensions, temperate and pressure of the extract separator has been carefully calculated so that extract sitting in the bottom of the separator during extraction is immersed in a pool of liquid co2 at 62F. This means that it will not degrade from the over heating that many other brands subject extract to and it will not come out of the separator in a frozen block of dry ice which immediately draws moisture out of the air which dilutes and acidifies your extract.

Further to the right, we have a secondary separator for catching overflow should operator error cause the first separator to overflow. Next is the cooling tower and accumulator which turns co2 vapor back to liquid. This is the complex thermodynamic process that makes Eden Labs co2 extractors superior.

Future projects and upgrades include inline dewaxing through precise filtration and true automation. By true, we mean automation that actually makes the extraction process faster, easier and less labor intensive.

All the hard, physical work in supercritical co2 extraction revolves around grinding the herb, placing it into the extractor vessel, and then removing it after it’s extracted. True automation would do all this automatically prior to starting up the extraction. Eden Labs is working with an industrial agriculture firm to design this next level automation.

While many others jumped into the extractor market in recent years thinking it was a quick get rich scheme, Eden Labs has steadily innovated and improved its designs for 26 years. We will continue this for many more years.