ORC Extractor

This is my 2 ounce sample size ORC Extractor.

This unit is capable of processing around 2 ounces of biomass at one time. However due to the nature of the process, the sample can be replaced with new material.

The solvent volume is around 700ml.

This system is able to be used with high pressure, vacuum, or ambient pressure. It can be run active or passive.

By changing a single valve, the mode of operation is selected. When the valve is closed, the system is in ORC mode. When the valve is open, the system is set for standard CLS operation.

When a seperate collection container is added, the system can be used to dry biomass, and recover solvent. Straight distillation from liquid (for purification) can be accomplished, in the same manner.

#orcextractor #orctek #orctech #orctekextractor #orctechextractor


Starting at the top:

There is a vacuum line, connected thru an end plate, to a jacketed column.

The system, when in ORC mode, operates nicely under a vacuum. The vacuum takeoff is placed above the jacketed column, for a reason.

The jacket of the column is our chiller. Numerous methods can be used to cool it. The main point is that the column must be a lot colder than the collection pot, at the bottom of the setup.

Vacuum usually needs a trap, but here we use the whole condensing column as a trap. The column is packed with SS wool, for better thermal transfer.

Below the condenser column is a split.

The straight through side consists of 4 parts: the sample chamber at the top, followed by a tee (top of ORC loop), a valve under that, followed by another tee (bottom of ORC loop)

Under that is the bottom split.

The other sides of the splits are connected by a continuous tube, to form a rising vapor path.

The hose to the side is the ORC loop.

This hose loop must stay elevated above the sample chamber level, but also kept below the bottom of the upper split.

Small sight glass at the bottom is optional. It is there to monitor when solvent dumps are occuring.

That brings us to the bottom.

Nothing special here. Collection spool with a sight glass and a splatter platter. Also standard compound gauge and valve, with vacuum connector.

One thing different about the collection pot.

If used in ORC mode, the solvent will be boiling for extended periods. Use boiling stones (SS balls work well and are easy to remove later).

Oops, forgot a vital piece.

There has to be a screen gasket between the sample chamber and the upper tee.

Without that gasket, sample material will flow into the collection pot. I use a 5 micron filter, but a 100 micron should suffice.

Another point of interest, that is actually a very serious warning.

The gaskets that you use are important.

The solvents used in extractions vary in properties, but a prominent characteristic is that some solvents eat some types of gaskets.

Having gaskets blow, because the solvent ate through them, is something that can happen.

Since the range of solvent choices is wide, I suggest that PTFE gaskets are the ideal choice, since PTFE is OK with just about everything. That said, they are terribly difficult to seal.

A couple of compromise solutions are available…Envelope gaskets and Tuf-Steel gaskets

Envelope gaskets are PTFE, on top of (enveloping), a different material.

Tuf-steel are a 50:50 mix of PTFE and nano-sized stainless steel.

Either one will be a good choice, as they are both PTFE types. Get them as your first choice, don’t bother buying the others.

For reference: silicone seals are cheap, but are only good with alcohols…never use them with alkanes.

This system, as shown will easily handle solvents with sea level boiling points greater than -15 F, or so. Butane, Dimethyl Ether, Pentane or hexane would be fine.

Running straight propane, or even propane mixes would probably require a much larger chiller. The best achievable, with 99% ISO/DI slurry, at around -110 F, but the column is short. Explosive gas through the vacuum pump is not good.

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Looking at the above, I mentioned solvents that were all alkanes.

This system can also be run using alcohols. Although, due to their higher boiling points, even under vacuum, slight heating would be needed to obtain good results.

The stuff with lower BP’s, under vacuum, will boil without additional heat input, allowing a room temperature process. As long as the top is cold, it will continue to work, passively.

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This system can be scaled up for larger samples.

I have plans for both a 10lb sample size and 20lb sample size. At the 20lb size, you could extract around 400lbs of biomass, in around 5-6 hours, with all crude collected in a single liquid fraction, of around 70 liters of solvent.

The large size ones are designed to operate continuously, until they are shut down for cleanout. Process continues, even during sample changes.

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At the 20lb sample size, I stated that 400lbs could be processed in around 5-6 hours. While this is a true statement, it doesn’t illustrate the true value of the process.

The truth is, if you are willing to work longer hours, the theoretical capacity is closer to 1200lbs, before a cleanout is needed. It depends on the % of desirables in your biomass. Theoretically the 70 liters of solvent would not be saturated until you were around 70 liters of crude (140 liter total 1:1).

I want to point out that even the small 2 ounce sample size, shown in the picture above., would have the ability to extract around 12lbs of biomass, gathering around 1.5lbs of crude. The small one has a solvent volume around 700ml.

Of course to do this, you would have to do an unreasonable number of sample swaps, but it could be done.

This tek is powerful.

Once a sample is exhausted, it will still be pretty wet, so spinning will be needed. The solvent recovered during the spin would be used to wet new samples. You want to keep returning as much solvent to the system, as possible. Try to add as little fresh new solvent as possible, to keep final volumes low.

Here is a parts list. Fair warning, Valves, Tees and Sight Glass parts all seem to be odd sizes. The pieces that I used will fit together properly. Be careful with changing pieces. All pieces are SS304.

4 x 1.5" x 5.5" Tee Spools
2 x 1.5" 90 Degree Bends
1 x 1.5" x 24" Spool
1 x 1.5" x 6.5" Inline Sight Glass
1 x 1.5" x 4.5" Inline Valve
1 x 1.5" x 2" Spool (suggest using filter holder)
1 x 1.5" Screen Gasket (5 micron or tighter)
14 x 1.5" Gaskets (PTFE or envelope type preferred)
15 x 1.5" Tri-Clamps
1 x 1.5" x 18" Jacketed Dewaxing Column with bottom 1/4" female NPT
3 x 1.5" End Caps with 1/4" NPT female fitting
4 x 1/4" male NPT to JIC male adapter
4 x 1/4" ball valve (1 male and 1 female end)
SS304 mesh packing
78" Braided SS Chemical hose, with 1/4" female JIC each end

The small sight glass at the bottom is not needed, was included to observe tipover.


It should be obvious, but I will say it anyway. The collection pot pieces are not listed in the parts list above. As shown in the picture, the pot on this setup is a 4" diameter, with a sight glass side port and a splatter platter. The lid has a 1.5" Tri-Clamp port and a female NPT port, with a gauge, ball valve and JIC connection attached. Standard collection pot stuff.

The size of the pot is not really important, it just needs to be large enough to hold all of your chosen solvent.

In the picture, I used an 18" spool and a 6" spool to form the riser side. The parts list shows a 24" tube instead. Doesn’t matter how you get the proper length, but more pieces means more gaskets, clamps and joints to tighten.

If you need larger sample sizes, you can add more spools. You just have to add exactly the same number of inches to the riser side.

If the riser side gets too long, you will get condensation inside. If this occurs, warm the riser.

Oh yeah, since nobody cared to even guess, I will tell you.

O.R.C. = Organic Rankine Cycle … not the big green character

Also referred to as a heat engine.


Normally, mechanical energy is pulled out of these systems, through the use of a turbine in the riser. That is not being done in this setup.


Couple more comments.

The design is quite tall, top heavy, and awkward. As shown, it weighs around 40 pounds. It definitely requires some sort of support. I use velcro to attach to a shelving unit.

The usefulness of the small unit is questionable, but it will function properly. However, it was built mostly for testing “proof of concept”. It is with the upscaled sizes that this process becomes sensible.


Here is a picture of a different configuration. I don’t remember the exact weight capacity, but think it will hold more than a pound. Here the collection pot would need to be a larger diameter (than 4"), as much more solvent would be used. Note that the ORC return is below the riser split and there is no central valve…a plate gasket was used instead (so no CLS function available)

Stainless Steel tinker toys for big boys

The 2 ounce sample size is a better design, as all ORC parts reside completely between the splits (where the bends are).


that’s a spacing miracle.
i like it.


Looks like a big soxhlet apparatus


It is a soxhlet … in steel