banana buds builds a butane extraction and recovery system

[banana buds]

before getting started, I need to say a huge thanks to those who made this project possible. gray wolf, jump, foaf, doublekindness, and others have been very kind to share their experiences so that i may stand on the shoulders of giants. if you are planning on embarking on a project like this, you would be well served to read their respective threads several times each.

My system is built as follows:

-5 gallon pressure pot for the flask
- 4"D x 24"L extraction column - 304 SS tri-clamp spool section
-appion g5 twin recovery machine
-IP n-butane (99.5%) tank for the solvent

the column end caps are also 304 SS. I had my machinist tap holes into the end caps to allow me to put fittings and a gauge on my column. I currently have 1/4" brass flares (using 1/4" MPT x 1/4" FL pieces) for my hose connections, and a 3/8" ball valve for the dump line into the flask.

the column top cap has a pressure gauge ( 30"Hg to 100 PSI), two spare 1/4" flare fittings that are capped, and two 1/4" flares that are used for pre-vacuum and butane breather/overflow.

the column bottom cap has a 1/4" flare fitting for the butane fill line, and has the 3/8" NPT ball valve that dumps down into the pressure pot.

the pressure pot is completely unmodified at this point other than removing a section of handle to clear the column. it sits in a 27 gallon tote filled about halfway with water that is used to heat the system during recovery. I tried using a 300 watt aquarium heater but it was inadequate (although better than nothing). my current solution is a submersible pump that pushes the bath water through a 1/4" copper heat exchanger coil which is currently resting in a large crock pot cranked to full heat. this gives me a pretty constant 100*F bath around the flask, which I am mostly happy with at this point.

when using a scale for the tank (which is not 100% of the time), i have a tif 9010 that works great. lines are all standard hvac type lines that are rated for handling much more pressure than this system should ever see. in addition to the gauges on both the column and flask, i have a set of yellowjacket manifold gauges that control fill/recovery. altogether if you count the gauges on the appion, there are 6 different ones in the system! yowza!


my initial gasket sets were white platinum-cured silicone, but these have proven unsuitable as they expand after some period of use and will no longer even fit the flanges.

i'm using 2mil teflon PFA pail liners (5 gallon size) to avoid scraping the flask. my procedure here is to carefully slip the bag in and fold the top over the rim of the pressure pot. i then snake a vacuum line in under the bag and suck out as much of the air underneath as possible so that the bag is tightly sucked against the sides of the pressure pot. the bag does not appear to cause any issues with the lid/pot seal, and allows me to quickly and easily remove a batch from the system and reset with another bag.

inside the pressure pot i have a tube that has 200-hole stainless cloth over the end to catch any particles before they are dumped into the pot. this also directs dumps into the middle / bottom of the pot, since my column is actually dumping through a hole that is offset in the lid.

for particle filtration, i have 100-hole stainless cloth discs pushed into either end of the column (3-4 per end for safety) and then



my current running procedure is thus:

1) pack column with approx 500g of material and put filter discs into ends.

2) put teflon bag in pot, vacuum it to the pot, put lid on.

3) mount column, tighten tri-clamps and then double check all hoses and fittings for tightness and proper settings.

4) fire up the vacuum pump and pull a good hard vacuum on the whole system for about 30 minutes.

5) fill column (remember this is a bottom fil) until the top breather line feels cold - this ends up being around 5 or 5 1/2 lbs of butane.

6) shut breather and fill lines, turn on recovery machine and pull pressure pot down to 10" vacuum (this takes a few minutes)

7) open dump valve to dump butane into pot. once pressure is equal between pot and column, top breather line is opened to allow any last dribbles to make their way down.

8) turn on recovery machine, and run until it gets whole system down to 10" vacuum (with current bath temps this usually leaves 2-4 oz of butane still in the system).

9) repeat steps 5-8 another 3 times - for a total of 4 butane soakings

10) allow appion to pull all but the last 2oz of butane back into the system for final run, and then use vacuum pump to pull hard vacuum

11) crack machine open, lift bag of extract out. lay it out on a table and warm areas with a hair dryer in order to squeegee everything into one spot using a plastic card. throw the whole bag into freezer until the big cake of extract is solid enough to pull out.




issues that i am grappling with right now:
-extract seems to come out several shades darker and somewhat more gooey consistency than the same starting material does with other extraction methods.
-it takes a long time to recover 5 1/2lbs of butane, four times over. heat bath is good, i need to put my butane tank in a chilled reservoir. ideally i will upgrade and have separate tanks for filling and recovery.
-current ball valve is finicky and has started to leak a tiny amount when at 1/2 open - will probably upgrade this to a sanitary ball valve that can have the seals replaced easily
-silicone gaskets are no good for extended use, going to try out viton and buna-n
-stuffing filter discs into column is unreliable. once a suitable gasket is tested, will order one that has the right size of mesh already built in.
-need to upgrade to larger lines (current ones are 1/4") and possibly switch some parts to hard tubing in order to allow quicker and more efficient recovery / fill / vacuum on the system.



right now i am seeing 13-18% w/w yield from trim depending on source and strain. this makes my batches anywhere from 50g up to 80+g depending on what i'm running and how much i pack into the column. i am fine with this batch size for now but my next milestone is getting it so i can run a whole batch in much less time, increasing daily throughput (only 1-2 batches are practical to do in a day right now, when i have other stuff to deal with).

 

[Flying High]

Awesome read and strong work getting your own system up and running!!! Any advice for someone just putting their first unit together; other than reading all of the appropriate threads several hundred times over?

I am a little concerend about the gauges I see being rated for many refridgerants, but not r-6oo specifically?

I hope to be joinging the club soon; I thought I found a brand new pump for half price today from a friend who is a HVAC tech. Turns out the Pinnacle machine is exactly what Ricky Bong's describes as not working; so I hit send on the Appion unit. If I wouldn't have read GreyWolf's thread so many times, I may not have remembered to look there for a description of what not to use...

Now I am working on my order from Glacier Tanks for the Stainless triclamp stuff, and then just some odds and ends including the 99.5% n-butane...

I like the idea of a sanitary ball valve on the main column; especially one of the tri-clamp ball valves. I think I may run 1" from column into my pressure vessel just so I can use one of those tri-clamp ball valves they have at Glacier. Even though it will cost me a little more, I feel like using tri-clamp fittings from the column almost into the pot will make cleaning or maintenance that much simpler.

thanks for posting, i appreciate the information more than I can say...

 

[Gray Wolf]

before getting started, I need to say a huge thanks to those who made this project possible. gray wolf, jump, foaf, doublekindness, and others have been very kind to share their experiences so that i may stand on the shoulders of giants. if you are planning on embarking on a project like this, you would be well served to read their respective threads several times each.

Excellent job bro! Congratulations on forging forward!

My system is built as follows:

-5 gallon pressure pot for the flask
- 4"D x 24"L extraction column - 304 SS tri-clamp spool section
-appion g5 twin recovery machine
-IP n-butane (99.5%) tank for the solvent

the column end caps are also 304 SS. I had my machinist tap holes into the end caps to allow me to put fittings and a gauge on my column. I currently have 1/4" brass flares (using 1/4" MPT x 1/4" FL pieces) for my hose connections, and a 3/8" ball valve for the dump line into the flask.

the column top cap has a pressure gauge ( 30"Hg to 100 PSI), two spare 1/4" flare fittings that are capped, and two 1/4" flares that are used for pre-vacuum and butane breather/overflow.

the column bottom cap has a 1/4" flare fitting for the butane fill line, and has the 3/8" NPT ball valve that dumps down into the pressure pot.

I would consider a 3/4" or 1" for the lower dump valve, for faster pump down. A 3/8" recovery line to the pump makes a big difference too.

When dealing with vacuum, there is not much pressure involved and there are not as many gas molecules for the pump to grab hold of. In addition, the gas molecules are further apart, so they have less attraction to one another, to pull each other along.

I got my pre threaded end caps with both female and male NPT fittings from Glazier tank.

the pressure pot is completely unmodified at this point other than removing a section of handle to clear the column. it sits in a 27 gallon tote filled about halfway with water that is used to heat the system during recovery. I tried using a 300 watt aquarium heater but it was inadequate (although better than nothing). my current solution is a submersible pump that pushes the bath water through a 1/4" copper heat exchanger coil which is currently resting in a large crock pot cranked to full heat. this gives me a pretty constant 100*F bath around the flask, which I am mostly happy with at this point.

I recommend cranking up your temperature. I use 200F and it will cut your time in more than half.

Getting the heat back out of the butane at the recovery tank is also key, as the recovery pump is working against that back pressure.

when using a scale for the tank (which is not 100% of the time), i have a tif 9010 that works great. lines are all standard hvac type lines that are rated for handling much more pressure than this system should ever see. in addition to the gauges on both the column and flask, i have a set of yellowjacket manifold gauges that control fill/recovery. altogether if you count the gauges on the appion, there are 6 different ones in the system! yowza!


Good idea having as many gauges as possible to keep track of things while wringing out the system. The gauges on the Appion are a joke, which I studiously ignore, except to note what they generally say when trouble shooting.

After shake down, I rely on a single gauge on the pressure pot and the new system will have a single analog gauge there as well, plus three preset pressure switches.

my initial gasket sets were white platinum-cured silicone, but these have proven unsuitable as they expand after some period of use and will no longer even fit the flanges.

i'm using 2mil teflon PFA pail liners (5 gallon size) to avoid scraping the flask. my procedure here is to carefully slip the bag in and fold the top over the rim of the pressure pot. i then snake a vacuum line in under the bag and suck out as much of the air underneath as possible so that the bag is tightly sucked against the sides of the pressure pot. the bag does not appear to cause any issues with the lid/pot seal, and allows me to quickly and easily remove a batch from the system and reset with another bag.

inside the pressure pot i have a tube that has 200-hole stainless cloth over the end to catch any particles before they are dumped into the pot. this also directs dumps into the middle / bottom of the pot, since my column is actually dumping through a hole that is offset in the lid.

for particle filtration, i have 100-hole stainless cloth discs pushed into either end of the column (3-4 per end for safety) and then

We've had stellar luck with a 130 micron stainless screen over both ends of the column to hold filters in place, and then just wadding up a couple coffee filters and packing them in the ends of the column, between the plant material and the screens. The filter plugs work great and we end up filtering out very little plant material when we wash the oil out of the pot with alcohol and prefilter before winterization.

my current running procedure is thus:

1) pack column with approx 500g of material and put filter discs into ends.

2) put teflon bag in pot, vacuum it to the pot, put lid on.

3) mount column, tighten tri-clamps and then double check all hoses and fittings for tightness and proper settings.

4) fire up the vacuum pump and pull a good hard vacuum on the whole system for about 30 minutes.

5) fill column (remember this is a bottom fil) until the top breather line feels cold - this ends up being around 5 or 5 1/2 lbs of butane.

6) shut breather and fill lines, turn on recovery machine and pull pressure pot down to 10" vacuum (this takes a few minutes)

7) open dump valve to dump butane into pot. once pressure is equal between pot and column, top breather line is opened to allow any last dribbles to make their way down.

I would recommend not opening the dump valve at this point, but instead opening the top vent and the butane feed valve. Leave it open for the same amount of time that it took to flood the column the first time, and then close the vent, followed by the butane feed valve, to keep the column full.

Every time the recovery pump pulls the system back down to -10hg, repeat the flood/overflow step, until the last cycle, and then open the dump valve.

No need to pump the columns down until the last cycle, at which time I add heat, because they will ice up when the butane starts evaporating off.

8) turn on recovery machine, and run until it gets whole system down to 10" vacuum (with current bath temps this usually leaves 2-4 oz of butane still in the system).

9) repeat steps 5-8 another 3 times - for a total of 4 butane soakings

10) allow appion to pull all but the last 2oz of butane back into the system for final run, and then use vacuum pump to pull hard vacuum

11) crack machine open, lift bag of extract out. lay it out on a table and warm areas with a hair dryer in order to squeegee everything into one spot using a plastic card. throw the whole bag into freezer until the big cake of extract is solid enough to pull out.




issues that i am grappling with right now:
-extract seems to come out several shades darker and somewhat more gooey consistency than the same starting material does with other extraction methods.
-it takes a long time to recover 5 1/2lbs of butane, four times over. heat bath is good, i need to put my butane tank in a chilled reservoir. ideally i will upgrade and have separate tanks for filling and recovery.


Using the same tank for flooding the column and recovery, allow the use of push pull with the pumps, which is important because butane operates at such low pressure when cold.

-current ball valve is finicky and has started to leak a tiny amount when at 1/2 open - will probably upgrade this to a sanitary ball valve that can have the seals replaced easily
-silicone gaskets are no good for extended use, going to try out viton and buna-n
-stuffing filter discs into column is unreliable. once a suitable gasket is tested, will order one that has the right size of mesh already built in.

I use Neoprene, Viton or buna n gasket material. The cheeks of my ball valves are PTFE, but the seals are Viton.

-need to upgrade to larger lines (current ones are 1/4") and possibly switch some parts to hard tubing in order to allow quicker and more efficient recovery / fill / vacuum on the system.

The dump line and the recovery line are the two critical ones.

right now i am seeing 13-18% w/w yield from trim depending on source and strain. this makes my batches anywhere from 50g up to 80+g depending on what i'm running and how much i pack into the column. i am fine with this batch size for now but my next milestone is getting it so i can run a whole batch in much less time, increasing daily throughput (only 1-2 batches are practical to do in a day right now, when i have other stuff to deal with).

That is not an unreasonable yield for trim, which can be all over the place. I gauge removal efficiency on bud, which is more uniform. Our best yield is around 27%, the worst 5.8%, and average is about 23% BHO AA from our indoor plants.

As far as color pickup, the butane will eventually pickup water and darken the extraction some if you don't dry it out, but in thin films, the two extractions look about the same. Here are a couple of examples. The larger sample was done with single pass columns and the smaller one with the Terpenator.

The smaller one is also a part of an early experiment on color pickup by cycle, and it is from cycles 4 and 5, where we now get all the oil in about three cycles. Note the faint electric green hue.

 

[banana buds]

Awesome read and strong work getting your own system up and running!!! Any advice for someone just putting their first unit together; other than reading all of the appropriate threads several hundred times over?

I am a little concerend about the gauges I see being rated for many refridgerants, but not r-6oo specifically?

I hope to be joinging the club soon; I thought I found a brand new pump for half price today from a friend who is a HVAC tech. Turns out the Pinnacle machine is exactly what Ricky Bong's describes as not working; so I hit send on the Appion unit. If I wouldn't have read GreyWolf's thread so many times, I may not have remembered to look there for a description of what not to use...

Now I am working on my order from Glacier Tanks for the Stainless triclamp stuff, and then just some odds and ends including the 99.5% n-butane...

I like the idea of a sanitary ball valve on the main column; especially one of the tri-clamp ball valves. I think I may run 1" from column into my pressure vessel just so I can use one of those tri-clamp ball valves they have at Glacier. Even though it will cost me a little more, I feel like using tri-clamp fittings from the column almost into the pot will make cleaning or maintenance that much simpler.

thanks for posting, i appreciate the information more than I can say...

i looked at both glacier tank and gvc direct and i went with gvc as they were cheaper on some items and also did custom sizing on the spool sections in diameter i wanted to use. ymmv but definitely take a look at the gvc site.

i would say gray has the best advice here in general, so i'll defer to him.

one thing i found was that sealing my fittings with teflon tape was a pain, i'd use a thread sealant if i was doing it again, or at least use a lot of teflon the first time around. definitely use soapy water and pressure test your system to check for ANY leaks, and then do a vacuum test as well. don't want to be blowing that expensive n-butane out of leaks, both for cost and safety reasons.

 

[banana buds]

That is not an unreasonable yield for trim, which can be all over the place. I gauge removal efficiency on bud, which is more uniform. Our best yield is around 27%, the worst 5.8%, and average is about 23% BHO AA from our indoor plants.

As far as color pickup, the butane will eventually pickup water and darken the extraction some if you don't dry it out, but in thin films, the two extractions look about the same. Here are a couple of examples. The larger sample was done with single pass columns and the smaller one with the Terpenator.

The smaller one is also a part of an early experiment on color pickup by cycle, and it is from cycles 4 and 5, where we now get all the oil in about three cycles. Note the faint electric green hue.

so the procedure (which my quote did not pick up) that you are outlining basically keeps the column filled with butane at all times? flood it, then re-flood it to push the first flood out the vent line?

and your pictures are neat, but you should see some of the batches i'm pulling. one of them came out GREEN GREEN GREEN, and in general they are all darker and have at least a slightly green tinge. wild stuff, but problematic when you are dealing with picky people. other than a filter dryer (which i have one that i need to install) how would i figure out what kind of moisture is in my tank of butane right now?

 

[Hydrosun]

Reading all I can and trying to learn. Thanks for putting your information out there for us.

 

[banana buds]

here's one of the greener batches that has come out of the machine, and this is from my own trim that i've blown some of it other ways with no green tint at all.

 

[banana buds]

and a quick shot of the majority of the setup (missing vac pump, water bath, etc)

 

[Gray Wolf]

so the procedure (which my quote did not pick up) that you are outlining basically keeps the column filled with butane at all times? flood it, then re-flood it to push the first flood out the vent line?

Yes. Residence time affects temperature, which affects extraction rates.

and your pictures are neat, but you should see some of the batches i'm pulling. one of them came out GREEN GREEN GREEN, and in general they are all darker and have at least a slightly green tinge. wild stuff, but problematic when you are dealing with picky people. other than a filter dryer (which i have one that i need to install) how would i figure out what kind of moisture is in my tank of butane right now?

Robinaire makes some inline moisture gauges for their refrigeration recovery machines. We have a Robinaire refrigerant recycle system, that pumps liquid through a filter dryer and has a visable moisture sight gauge that changes color.

Another method to dry out the butane, would be to pack a column with molecular sieve and circulate the butane through it using the push pull of your recovery pump.

I also heard from a reclaimer, who lets his tank sit in ice water for an extended period and then pumps off the butane, leaving most of the water behind.

 

[Gray Wolf]

and a quick shot of the majority of the setup (missing vac pump, water bath, etc)

View Image

Nice rig!

Good job sorting out the Teflon bag issue. That allows the use of a cheaper lower end, even if you choose to wash out the bag and winterize later.

I haven't had good luck with that type of inline valve in the butane liquid hose. I originally had one, but took it out after it started leaking.

 

[Gray Wolf]

here's one of the greener batches that has come out of the machine, and this is from my own trim that i've blown some of it other ways with no green tint at all.

View Image

I've made it that green before, when I ran long soaks, or continued to run cycles on depleted material.

You also appear to have some water in your system.

You can get rid of some of that color by winterizing and then if you stick the alcohol mixture in bright sunlight for a few hours, it will breakdown the rest of the chlorophyll.

UV is the enemy of cannabinoids, but it doesn't happen in the blink of an eye, or the cannabinoids would never survive being in sunlight in the first place. Not a cure for greeeeeeeeeeeeeen material, but it will take out green tints without totally destroying the oil.

How are your preparing your material for packing?

 

[banana buds]

I've made it that green before, when I ran long soaks, or continued to run cycles on depleted material.

You also appear to have some water in your system.

You can get rid of some of that color by winterizing and then if you stick the alcohol mixture in bright sunlight for a few hours, it will breakdown the rest of the chlorophyll.

UV is the enemy of cannabinoids, but it doesn't happen in the blink of an eye, or the cannabinoids would never survive being in sunlight in the first place. Not a cure for greeeeeeeeeeeeeen material, but it will take out green tints without totally destroying the oil.

How are your preparing your material for packing?

well as far as the tinted batches, they probably won't be in my hands long enough to bother trying to remove the color. if they are, i will definitely give it a try, although sourcing 190-proof in my area is difficult at best, but appears to be illegal for the average joe.

if i pick up an empty recovery tank i'm thinking i can juggle the butane around to pass it through a filter dryer a few times. putting molecular sieve in the column sounds great, but sourcing it in the next few days (i'm intending to be running the machine daily, downtime is an issue) is not necessarily practical unless you have an idea of the kind of outfits that would sell it in the quantities i need.

DIY idea: what about packing the column with something that will absorb water but not butane? the first thing that comes to my mind is just regular salt. in theory it would work as the butane would easily pass through it, water would be snatched, and nothing should be in salt that could make its way back with solvent vapors....

this idea is obviously only good in this case where i am willing to devote a chunk of time to remedial moisture removal, i do need to get my filter dryer into the system, although i'm not sure my little one (032 size) is going to cut it if i've got enough moisture in the 'tane to cause bad batches after only running around 12lbs of material in the machine thus far... any thoughts on a more industrial scale solution?




here's what i have in mind for going two-tank:
-one tank holds the butane at the beginning, and sits at room temp or maybe even a little warmer to increase output pressure and thusly decrease fill time
-the other tank sits in a cold bath (either 39*F via chiller, or maybe do something with dry ice and 90% iso bath to get REAL cold) so that it has a very low pressure.

a fringe benefit is that this would also gain me the ability to be adding and removing butane from the system at the same time. this would alllow experimenting with things like a sustained blow-through done at whatever recovery rate is being achieved. the main point is just that i noticed running a chilled tank filled slower and thus increased the amount of time i'm stuck soaking. i don't like not having control over all variables.

 

[foaf]

good work, I like your design.

 

[knowhere]

Nice column, how much did that spool cost you? I have seen 4" spools from GW kents wine products site for around $44.50ea but these are only 12" long.

I have bids in from gvc for teflon and borosilicate glass sight-glasses that are 1' - 2' in length in both the 2" id and 4" id sanitary (tri clamp) fitting. I do find their prices for fittings, especially sight-glasses and adapters to be a little higher then other places though...

where did you get your paint pressure pot and what is its max working pressure rated to? link please

Currently we are using 5 gallon (20 liters) and 2.6 gallon (10 liters) alloy products pressure vessels atm as well as 2" id tri clamp spools 24" length. the alloy products vessels, they are electro-polished and fit for pharmacological production with dip tubes and all but they sure are pain to get liners in and out of even with the 6.4" x 5.5" oval opening..

For the npt thread sealant use "yellow gas line teflon tape", it is much much thicker and you only need to wrap the threads 2 - 4 times tightly and then really tighten up on the wraping to tension tear the tape, this causes the end of the torn tape to adhese to the tape under it sealing the wrapped threads tightly so you have no loose tail of teflon tape hanging off, when you wrap the threads make sure you wrap them in the correct direction so that screwing the threads together does not loosen the tape wraping.

the colder the solvent passed through the column the better tasting and less green I find the end product to be, more often then not unless it is my second run on material I am getting more sparkly golden salt water taffy or clear amber, this is also strain dependent, some strains have more waxes then others. Also the temp you bake off your solvent in evaporation effects oil darkness as well, too high and you darken what could have been a golden or amber too black.


Awesome work and thank you for contributing your experience on your adventure in this wonderful land of BHO solvent recycling systems

 

[banana buds]

Nice column, how much did that spool cost you? I have seen 4" spools from GW kents wine products site for around $44.50ea but these are only 12" long.

I have bids in from gvc for teflon and borosilicate glass sight-glasses that are 1' - 2' in length in both the 2" id and 4" id sanitary (tri clamp) fitting. I do find their prices for fittings, especially sight-glasses and adapters to be a little higher then other places though...

where did you get your paint pressure pot and what is its max working pressure rated to? link please

Currently we are using 5 gallon (20 liters) and 2.6 gallon (10 liters) alloy products pressure vessels atm as well as 2" id tri clamp spools 24" length. the alloy products vessels, they are electro-polished and fit for pharmacological production with dip tubes and all but they sure are pain to get liners in and out of even with the 6.4" x 5.5" oval opening..

For the npt thread sealant use "yellow gas line teflon tape", it is much much thicker and you only need to wrap the threads 2 - 4 times tightly and then really tighten up on the wraping to tension tear the tape, this causes the end of the torn tape to adhese to the tape under it sealing the wrapped threads tightly so you have no loose tail of teflon tape hanging off, when you wrap the threads make sure you wrap them in the correct direction so that screwing the threads together does not loosen the tape wraping.

the colder the solvent passed through the column the better tasting and less green I find the end product to be, more often then not unless it is my second run on material I am getting more sparkly golden salt water taffy or clear amber, this is also strain dependent, some strains have more waxes then others. Also the temp you bake off your solvent in evaporation effects oil darkness as well, too high and you darken what could have been a golden or amber too black.


Awesome work and thank you for contributing your experience on your adventure in this wonderful land of BHO solvent recycling systems

pressure pot - http://www.paintsprayersplus.com/pr...on-Resin--Mold-Casting-Pressure-Pot-Tank.html

the spool section was $190.88, and after shipping came out to $215.76

 

[Gray Wolf]

well as far as the tinted batches, they probably won't be in my hands long enough to bother trying to remove the color. if they are, i will definitely give it a try, although sourcing 190-proof in my area is difficult at best, but appears to be illegal for the average joe.

if i pick up an empty recovery tank i'm thinking i can juggle the butane around to pass it through a filter dryer a few times. putting molecular sieve in the column sounds great, but sourcing it in the next few days (i'm intending to be running the machine daily, downtime is an issue) is not necessarily practical unless you have an idea of the kind of outfits that would sell it in the quantities i need.

DIY idea: what about packing the column with something that will absorb water but not butane? the first thing that comes to my mind is just regular salt. in theory it would work as the butane would easily pass through it, water would be snatched, and nothing should be in salt that could make its way back with solvent vapors....

this idea is obviously only good in this case where i am willing to devote a chunk of time to remedial moisture removal, i do need to get my filter dryer into the system, although i'm not sure my little one (032 size) is going to cut it if i've got enough moisture in the 'tane to cause bad batches after only running around 12lbs of material in the machine thus far... any thoughts on a more industrial scale solution?


Sodium chloride salt is water soluble and might introduce corrosive liquid into your system. I might be more inclined to try Water Keep or Silica Gel. http://www.water-keep.com/shop/, or http://www.deltaadsorbents.com/?gclid=CN6pouf97q8CFQ4zhwodNx2z3A


here's what i have in mind for going two-tank:
-one tank holds the butane at the beginning, and sits at room temp or maybe even a little warmer to increase output pressure and thusly decrease fill time
-the other tank sits in a cold bath (either 39*F via chiller, or maybe do something with dry ice and 90% iso bath to get REAL cold) so that it has a very low pressure.

a fringe benefit is that this would also gain me the ability to be adding and removing butane from the system at the same time. this would alllow experimenting with things like a sustained blow-through done at whatever recovery rate is being achieved. the main point is just that i noticed running a chilled tank filled slower and thus increased the amount of time i'm stuck soaking. i don't like not having control over all variables.

With push pull, it averages about 15 seconds for me to flood a 1 1/4" X 24" column, and 1 1/2 minutes to recover enough to drop the system pressure to -10hg.

As it has a volume of 37.4 cubic inches and a 4" X 24 would have a 301.6 cubic inch capacity, so the same technique would take about 2 minutes to flood and about 12 minutes to pull back down.

In looking at those numbers, I think we may have just located your dark color source.

My supply/ recovery tank is sitting in an ice bath, and yours is being subjected to the heat of compression, plus the heat from your water bath.

Secondly, my flood time is about 15 seconds and yours is over two minutes. The time to pump back down is proportionally longer at 12 minutes, which means that the plant material is in contact with the warming butane significantly longer.

By making short fast runs and chilling my butane, I suspect my average solvent temperature is lower than yours, which lowers my extraction efficiency, but keeps my material at a lower temperature.

The longer recovery time also means you are heating your oil longer.

The way you are set up, it would be super easy to slip in a 1 1/2" X 24" column to test it out and if you are local, I will loan you one with threaded end caps for the test to see if the differences in our systems is temperature.

Another thing you might do, is run two cycles and check the material with a microscope to see if you have removed the trichomes. With your long soak times, you may be over extracting.

 

[banana buds]

With push pull, it averages about 15 seconds for me to flood a 1 1/4" X 24" column, and 1 1/2 minutes to recover enough to drop the system pressure to -10hg.

As it has a volume of 37.4 cubic inches and a 4" X 24 would have a 301.6 cubic inch capacity, so the same technique would take about 2 minutes to flood and about 12 minutes to pull back down.

In looking at those numbers, I think we may have just located your dark color source.

My supply/ recovery tank is sitting in an ice bath, and yours is being subjected to the heat of compression, plus the heat from your water bath.

Secondly, my flood time is about 15 seconds and yours is over two minutes. The time to pump back down is proportionally longer at 12 minutes, which means that the plant material is in contact with the warming butane significantly longer.

By making short fast runs and chilling my butane, I suspect my average solvent temperature is lower than yours, which lowers my extraction efficiency, but keeps my material at a lower temperature.

The longer recovery time also means you are heating your oil longer.

The way you are set up, it would be super easy to slip in a 1 1/2" X 24" column to test it out and if you are local, I will loan you one with threaded end caps for the test to see if the differences in our systems is temperature.

Another thing you might do, is run two cycles and check the material with a microscope to see if you have removed the trichomes. With your long soak times, you may be over extracting.

well i can tell you the 2 minutes to flood is accurate, but 12 minutes to recover is something i wish was true. as it sits the system takes more like 50-70 minutes to recover all ~5lbs of butane once it's been dumped into the flask. i am baffled as to how you're recovering so quick, except that maybe the combined factors of the insulation from the teflon bag, lower bath temps, and less surface area per pound of butane being recovered....?

my goal has been maximum throughput on a per-hour / per-day basis, hence designing in a column that can pack so much at once. i know that normally tube diameters like mine are bad for blow-through due to channeling etc, but given that its acting as a soak chamber i felt it was an ok way to accomplish my goals. maybe i was wrong?

is it unreasonable for me to be trying to move 5lbs of butane through such a system with my one recovery machine? maybe i need to be considering the possibility of using multiple appions for the scale i'm trying to do? supposing i use one fill tank and two recovery tanks, or just tee two appions onto the recovery tank, might i be getting better results?

 

[knowhere]

what temp range is the outside edge and lid of your "flask" in the bath? might want to get some brisk heat cable and keep things between 125 - 160f with a dedicated temperature controller. the hotter the evaporation chamber the faster the solvent will boil off, but this also increases pressure on the system and temps approaching 250f will darken your oil and degrade the thc content as well as decarb the oil.


also mentioned is using 3/8" ID vacuum lines instead of 1/4" I just recently purchased materials to upgrade my own unit to 3/8" vacuum lines because I was experiencing longer recovery times.

how new are the seals on your appion?


What pressures are you seeing at what stages of your process?

most of the time mine are under 45 psi throughout my unit.

I am also curious about using multiple recovery machines to speed up recovery time, or perhaps even building my own recovery unit from components, I would prefer the condensers my butane passes through during vapor reclaim to also be at least 304 ss instead of copper or aluminum.

How dry is the material you are running?* wetter not cured material also = more green as the water in the material acts as a secondary solvent and grabs the chlorophyll. you can stand longer soak times with dryer material.

vacuum dessicated material work very well in this process, even better if they are frozen and if you can keep the column frozen during the run with cold solvent, also if you use tri clamp fittings with screened gaskets and unbleached coffee filters on top of those screens you will get less particulate / much cleaner product.

 

[Gray Wolf]

well i can tell you the 2 minutes to flood is accurate, but 12 minutes to recover is something i wish was true. as it sits the system takes more like 50-70 minutes to recover all ~5lbs of butane once it's been dumped into the flask. i am baffled as to how you're recovering so quick, except that maybe the combined factors of the insulation from the teflon bag, lower bath temps, and less surface area per pound of butane being recovered....?

my goal has been maximum throughput on a per-hour / per-day basis, hence designing in a column that can pack so much at once. i know that normally tube diameters like mine are bad for blow-through due to channeling etc, but given that its acting as a soak chamber i felt it was an ok way to accomplish my goals. maybe i was wrong?

is it unreasonable for me to be trying to move 5lbs of butane through such a system with my one recovery machine? maybe i need to be considering the possibility of using multiple appions for the scale i'm trying to do? supposing i use one fill tank and two recovery tanks, or just tee two appions onto the recovery tank, might i be getting better results?

Skinny columns relative to the openings in the ends, will always be more efficient. As the diameter of the column goes up, the rest of the system needs to follow.

Another underlying secret to fast recovery is a large surface area relative to the volume. You could use a larger paint pot to promote a larger boiling surface.

Two pumps would speed up recovery, especially if they were operating with separate lines to the lower pressure vessel and separate recovery tanks in cooled baths.

You could speed up the flood cycle with larger lines and/or higher differential pressure. As most tank valves are 1/4", perhaps two tanks on a common manifold might be a solution.

 

[knowhere]

only concern with running 2x recovery units would be over filling one of the tanks if the volume of solvent being used in a run is greater then a single tanks holding capacity, 1 appion might be a little faster then the other for multiple reasons. perhaps building a tank manifold and adapting it to larger volume propane tank with a longer dip tube and larger fittings, might be cheaper in the end this route then buying multiple purpose built recovery tanks