Very Low Budget Essential Oil Extractor Butane Recovery System

Pyewacket

Well-Known Member
Inspired by Fadedawg's Terpenator models and write-ups -- I have found myself wanting to try my hand at a VERY low budget strip-down version -- oil extractor. Absolutely nothing fancy about this, and it is very much specific to what I have been making (winterized BHO shatter). In fact (if this works--and it is a big IF) the only way to reclaim the oil from the collection vessel will be to dissolve it in ethanol and pour it it out -- as opposed to scraping it.

Here are some thoughts and concerns:
Copper - Yes I am using copper for the evacuation chamber. I am comfortable with using copper in distillation equipment construction. Copper is used world-wide in a variety of distillation apparatuses...it is used in many homes/municipalities for potable water -- it is even common in cooking-ware. Some folks are concerned with copper patina contaminating the product -- properly cared for copper will impart no contamination.

Pressure -- I have made similar vessels, and I have pressure tested them well above the PSIg/temp evaporation pressure of butane. I will be pressure testing these vessels once I receive my valves.

Stainless solder integrity. Over the years I have soft soldered stainless to copper and stainless to stainless with very good results. Using the correct flux and solder is imperative, but if one takes his time...the join is amazingly strong.

Cleaning without the ability to fully disassemble. One of the advantages of working with these two solvents is that they can naturally strip and remove most of what needs to be cleaned. Most homedistillers have boilers that are fully enclosed (except for still head path). Additional cleaning will be done with abrasive raschig rings that can be swirled inside the vessels...for extra cleaning.

Cost. I still need to purchase my valves and connection hose, but what you see in the photos is roughly $20 worth of materials. My guess, $65-$75.

Some photos of what I have thus far:

The copper evacuation tube is soldered onto a soldered sealed vessel. The vessel is two medium thickness stainless steel bowls soldered together. The vessel on the right will be the butane storage vessel.
20140105_160637.jpg


This is the top of the evacuation tube. I will solder a 1/4" stainless valve suitable NPT fitting to receive the stainless valve for this evacuation tube. The two threaded fittings will be sealed with gas appropriate Teflon tape.
20140105_160544.jpg


To construct the vessel. Both lips are tined(pre-solder coated). A torch applies the heat, and the two halves are melted together. I used these clasps to apply downward pressure as I am heating the perimeter to melt them together.
20140105_152948.jpg


The above step does a wonderful job of fusing. But to ensure a good seal...You need to back fill with solder. This takes a while. When finished, the joint must be cleaned with a grinder. This will reveal any air-pockets, and you will have to re-solder that spot.
20140105_154548.jpg

If done correctly, you get a nice THICK bead of fill...that is remarkable strong. This is the butane storage vessel. I will need to solder a valve into the vessel once they arrive.
20140105_160508.jpg

This is a passive extractor (no vacuuming device). Meaning, temperature variants will create vacuum/suction pressure and allow the butane to flow through the system. It is very much a distillation process when extracting the butane into to the storage container -- leaving behind the THC oil in the first container -- capturing the solvent in the storage container. The storage container will be stored in the freezer...at this temperature the PSIg should be nearly zero.

This is where I am in the process. Not sure anyone cares, but I will add additional information as I finish this build. Once I have the valves installed, I will try to do a better job of explaining the flow of butane and the way this mess should work.
 

LIBERTYCHICKEN

Well-Known Member
A tip from a plumber that works with SS

research the specific type of SS your useing and what to solder/braze it with, with SS minute differences can make all the difference in the world .

Also when fitting male to female SS NPT (or any thread) adapters , use the correct tape/ or paste designed specificly for SS, It costs alot more but is well worth it, Becouse SS is usualy so hard it is a bitch to make a proper seal , Let alone one that can withstand high pressure
 

Pyewacket

Well-Known Member
Thanks folks -- I will update once the valves are here.


A tip from a plumber that works with SS

research the specific type of SS your useing and what to solder/braze it with, with SS minute differences can make all the difference in the world .

Also when fitting male to female SS NPT (or any thread) adapters , use the correct tape/ or paste designed specificly for SS, It costs alot more but is well worth it, Becouse SS is usualy so hard it is a bitch to make a proper seal , Let alone one that can withstand high pressure
Thanks Liberty. I am lucky enough to be able to pull from Fade's parts list on the SS valves and fittings, but I did not consider the special Teflon. I will research that out, and I have no trouble paying extra. It is nice to finally run into a plumber that has worked with soldering SS. Through the years I have had chats with many plumbers and most think I am nuts when I mention it -- even my plumber neighbor.
 

Fadedawg

Well-Known Member
Inspired by Fadedawg's Terpenator models and write-ups -- I have found myself wanting to try my hand at a VERY low budget strip-down version -- oil extractor. Absolutely nothing fancy about this, and it is very much specific to what I have been making (winterized BHO shatter). In fact (if this works--and it is a big IF) the only way to reclaim the oil from the collection vessel will be to dissolve it in ethanol and pour it it out -- as opposed to scraping it.

Here are some thoughts and concerns:
Copper - Yes I am using copper for the evacuation chamber. I am comfortable with using copper in distillation equipment construction. Copper is used world-wide in a variety of distillation apparatuses...it is used in many homes/municipalities for potable water -- it is even common in cooking-ware. Some folks are concerned with copper patina contaminating the product -- properly cared for copper will impart no contamination.

Pressure -- I have made similar vessels, and I have pressure tested them well above the PSIg/temp evaporation pressure of butane. I will be pressure testing these vessels once I receive my valves.

Stainless solder integrity. Over the years I have soft soldered stainless to copper and stainless to stainless with very good results. Using the correct flux and solder is imperative, but if one takes his time...the join is amazingly strong.

Cleaning without the ability to fully disassemble. One of the advantages of working with these two solvents is that they can naturally strip and remove most of what needs to be cleaned. Most homedistillers have boilers that are fully enclosed (except for still head path). Additional cleaning will be done with abrasive raschig rings that can be swirled inside the vessels...for extra cleaning.

Cost. I still need to purchase my valves and connection hose, but what you see in the photos is roughly $20 worth of materials. My guess, $65-$75.

Some photos of what I have thus far:

The copper evacuation tube is soldered onto a soldered sealed vessel. The vessel is two medium thickness stainless steel bowls soldered together. The vessel on the right will be the butane storage vessel.
View attachment 2952721


This is the top of the evacuation tube. I will solder a 1/4" stainless valve suitable NPT fitting to receive the stainless valve for this evacuation tube. The two threaded fittings will be sealed with gas appropriate Teflon tape.
View attachment 2952725


To construct the vessel. Both lips are tined(pre-solder coated). A torch applies the heat, and the two halves are melted together. I used these clasps to apply downward pressure as I am heating the perimeter to melt them together.
View attachment 2952728


The above step does a wonderful job of fusing. But to ensure a good seal...You need to back fill with solder. This takes a while. When finished, the joint must be cleaned with a grinder. This will reveal any air-pockets, and you will have to re-solder that spot.
View attachment 2952729

If done correctly, you get a nice THICK bead of fill...that is remarkable strong. This is the butane storage vessel. I will need to solder a valve into the vessel once they arrive.
View attachment 2952731

This is a passive extractor (no vacuuming device). Meaning, temperature variants will create vacuum/suction pressure and allow the butane to flow through the system. It is very much a distillation process when extracting the butane into to the storage container -- leaving behind the THC oil in the first container -- capturing the solvent in the storage container. The storage container will be stored in the freezer...at this temperature the PSIg should be nearly zero.

This is where I am in the process. Not sure anyone cares, but I will add additional information as I finish this build. Once I have the valves installed, I will try to do a better job of explaining the flow of butane and the way this mess should work.
Hee, hee, hee, good to see fertile minds at work! Have fun, and play safe!

You can also have the valve ports TIG welded to the stainless. Solder is probably stronger at the folded lap joint where the two half hemispheres join, as given the natural joint design, you don't have access to the weld root for TIG.

With a folded lap joint, you can also add a bolt circle after soldering to take the strain off the solder.

I can't see how big the flats are on the bottom of the two bowls, but under pressure everything will want to be round and the bowls are thin walled. Heavy enough to withstand the pressure, but will deflect at relatively low pressure.

If you fill it with water first, and put air pressure on top of that to test it, if something does blow, there won't be as much compressed air involved and any failures will be less spectacular. It will also help reveal any leaks.
 

Pyewacket

Well-Known Member
Hee, hee, hee, good to see fertile minds at work! Have fun, and play safe!

You can also have the valve ports TIG welded to the stainless. Solder is probably stronger at the folded lap joint where the two half hemispheres join, as given the natural joint design, you don't have access to the weld root for TIG.

With a folded lap joint, you can also add a bolt circle after soldering to take the strain off the solder.

I can't see how big the flats are on the bottom of the two bowls, but under pressure everything will want to be round and the bowls are thin walled. Heavy enough to withstand the pressure, but will deflect at relatively low pressure.

If you fill it with water first, and put air pressure on top of that to test it, if something does blow, there won't be as much compressed air involved and any failures will be less spectacular. It will also help reveal any leaks.
These are very good ideas. I hadn't thought about adding water for the test...I will be doing that. I more than half expect the bottoms to ping out...should be exhilarating when they do- that could easily compromise my joins; I have been going around and around about soldering copper plates to the tops/bottoms of the bowls. I have added SS bolts to salad bowl/pot solders in the past...I may still add them.
 

Pyewacket

Well-Known Member
Ok, I couldn't wait. I wanted to see at what point the bowls would fail. So I decided to sacrifice one in the name of a large explosion. Since I did not have my valves, I installed a tire stem valve and pumped it up with a bike tire pump. I had the bowl on the other side of a wall and I pumped away. I could hear the top and bottom concavities Ping out at around 50PSI...I kept pumping and pumping until 130PSI...and BOOM~
20140106_154318.jpg

It ripped a large hole at the tire valve...and poped the two halves apart. Not sure how I feel about this. 130PSI seams high -- but wow that was a crazy explosion.

I wanted to add something about safety. The bowl was essentially surrounded by reinforced concrete...I was on the other-side of the concrete. This is incredibly dangerous otherwise -- dangerous anyway...However, I don't want to move forward unless I know that a vessel like this is safe enough to use; I felt compelled to push it to failure.
 

Fadedawg

Well-Known Member
130 psi is outside the normal operating range of a passive extractor, but not outside the pressure possible in a closed butane system that is heated.

I've never seen a Lil Terp above 50 psi, but have never heated ours hotter than 110F.

With multiple screw ups, I've seen a Terpenator hit 80 psi at 200F, and depending on the passive systems butane fill, it could go much higher.

I typically design to at least a 3X safety factor, but putting a lid on the larger Terpenators that would resist the deflection from a 3X pressurization would make it so heavy that lifting it for many people would be an issue, so I'm using a pressure relief valve, protected from vacuum by a spring check valve.

Another connection that might work at the valve port, and that is a bulkhead fitting, that would reinforce the area around it some, and resist tearing.
 

Pyewacket

Well-Known Member
130 psi is outside the normal operating range of a passive extractor, but not outside the pressure possible in a closed butane system that is heated.

I've never seen a Lil Terp above 50 psi, but have never heated ours hotter than 110F.

With multiple screw ups, I've seen a Terpenator hit 80 psi at 200F, and depending on the passive systems butane fill, it could go much higher.

I typically design to at least a 3X safety factor, but putting a lid on the larger Terpenators that would resist the deflection from a 3X pressurization would make it so heavy that lifting it for many people would be an issue, so I'm using a pressure relief valve, protected from vacuum by a spring check valve.

Another connection that might work at the valve port, and that is a bulkhead fitting, that would reinforce the area around it some, and resist tearing.
This is invaluable information. Although I have a butane psig/temp chart, I needed that real-world perspective. I have seen folks use those bulkhead fittings for keg connections etc....I will look into them. I will quest to find thicker/higher quality stainless containers. The ones I used were only a few bucks...Higher quality would only cost a few bucks more. Adding those stainless bolts around the lip of the bowls...is a good idea.

Thanks again~
 

LIBERTYCHICKEN

Well-Known Member
This is invaluable information. Although I have a butane psig/temp chart, I needed that real-world perspective. I have seen folks use those bulkhead fittings for keg connections etc....I will look into them. I will quest to find thicker/higher quality stainless containers. The ones I used were only a few bucks...Higher quality would only cost a few bucks more. Adding those stainless bolts around the lip of the bowls...is a good idea.

Thanks again~



Most small scrap metal dealers will sell you about anything they have for around double the price of scrap - It's a awesome budget resource
 

Pyewacket

Well-Known Member
Most small scrap metal dealers will sell you about anything they have for around double the price of scrap - It's a awesome budget resource
That is some very good advice...I go to one where I live and they have giant bins of various metals. One example, I purchased 12' of 2" type L copper for $75...A 10' stick at Lowes runs $170. They do require you to bring cash...
 
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