Approximate Decarb Time for Ethanol Extracted Crude

Help Support and Requests
, ,
1

Just looking for a ballpark consensus for those who decarb ethanol extracted crude in regards to the time to per volume ratio.

After extraction and solvent recovery, we’re loading the crude into a 100L jacketed stainless steel reactor and mixing/heating at 110 C (230F) while under vac (< -15psi).

Obviously the time it takes to fully decarb is dependent on several factors but for practical purposes, does 1hr/kg seem like a reasonable guideline?

Thanks in advance

2

Its not nearly as dependent on volume as you seem to think it is.

Since you have stir and vacuum just run it until there are no more bubbles when you stop stirring that will be your stop point, if it still bubbling, turn the stir back on and keep going . Since you are under vacuum you can turn up the heat some to speed it up a bit.

3 Likes
3

Thanks! That’s essentially what we’ve been doing so far, waiting until there are no more bubbles. I just wasn’t aware of, or haven’t been able to find, if there was a general relationship between time and volume based on a given temp. Was more just curious to help try and streamline the process so I dont end up bottlenecking but as time goes on, I’ll be able to gather more real time data to dial it in

4

Residual solvent (and water) will (both) change the temp profile your extract sees, and are probably the biggest source of variation folk see in decarb times.

Pull vac. Turn on heat. Once back to full vac, chances are you’re done…

Tune “how long” or “how close” to full vac is required based on in-house or 3rd party analytics.

2 Likes
5

this number seems excessive. Maybe at the temps you’re running the reactor at it could take this long but even then I don’t think so. We use a 100L jacketed glass at 140° - 145°C. We usually run between 35L - 50L with a 18% - 25% solvent load. Our decarb times don’t exceed 5hrs unless we load more than that in the reactor, and we see 70% - 80% THC analytically when we we’re done. So max we’re loading 50L - 25% solvent = 37.5L crude return in 5hrs we’re looking at 1hr/7.5kg. This can vary obviously but the lowest I would say we’ve seen is 1hr/3.5kg of finished crude!

1 Like
6

There are a few variables to answer your question.

  1. Surface area to Volume
  2. Residual solvents
  3. Temperature setting
  4. Power
  5. Transfer
  1. The surface area to volume will cause larger volumes to be exponentially slower to decarb.
  2. Residual solvents will boil and keep your oil from reaching decarb temperatures until they have evaporated off. They can also cause other problems during processing.
  3. The temperature the equipment is set too will affect decarb time. The higher the temperatures the shorter the decarb time, but there are problems that arise with using excessively high temperatures.
  4. Power of the heating element is important, especially for large volumes. Low power can lead to very long decarb times, because there is a lot of time wasted heating up the oil.
  5. Transferring oil into the equipment takes time, if you can move the oil as a liquid this will save you time.

A rate of 1hr/kg is reasonable in some settings. I used to take large pans of about 5kg of crude oil and put them on a hot plate and it would take about half an hour per kg to decarb, and another half an hour to heat up. I could spend another half an hour per kg offgassing volatiles while I did this, but I prefer to do this under vacuum.

2 Likes