I had old tane and ran it through sieve 2x and then even soaked it in sieve. I ended up losing a bunch of tane in the process, I couldve run all my material instead of all that effort. Now Ill just buy tane and use the mole sieve every time.
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You can, but you have to wash the dust off first, i was just killing 2 birds 1 stone. Inject into a mol sieve that was attached to my distillation pot and was then recovered right back into the system. You dont need a pump for a mol sieve, you need a mol sieve either way.
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one problem with running the sieve pre is that at the end you have wet tane. if you put it in a tank it can rust and i can tell you havent spent 600 on a stainless tank yet and neither have I.
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Thatās a cool idea, although the geometry is going to make it difficult to operate as a cyclone separator. Typically for liquid/gas or liquid/liquid cyclone separators the chamber is conical, so that the angular velocity increases as the fluid travels from point A to point B.
I guess it would help to know, whatās the application for this thing?
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*The application was to protect the pump and to remove water vapor., both of which it did well, without the added inconvenience of handling dusty beads. As the name implies, it is not a cyclone separator, it is cyclonic filter drier.
Tech makes the point that driers are not required, more about that later, but there is no argument that its discharging against the inside tangent of the can protects the element and the pump.
As to whether butane picks up water, the solubility of water in butane is 61 mg Lā1 (at 20 Ā°C (68 Ā°F))
There is little argument that the process picks up water and deposits it in the supply/recovery tank and when it reaches the dip tube it is injected instead of LPG.
We remediate that situation by regularly inverting the tank and venting accumulated water from the vapor valve.
As to the fine polish provided by a drier, unless you vacuum bake them out regularly, they become saturated and cease to remove water and if they were 100% effective there would be no accumulated water in the recovery tank.
We rotated cores daily and inverted and vented our tanks weekly without water issues, but it really depends on what you are running, at what temperature, etc.
When I say without water issues, I mean that it was always present when we vented, it just never reached the dip tube. That is when it screws up the process.
The other thing it does if you are using a carbon steel tank of course is rust, so stainless is best for that application, unless it must also meet DOT certification.*
PS: If you back fill your system with N2 instead of humidity laden atmosphere, there is no condensation to coat the inside of the piping, and if you vacuum down your system to -29.9" Hg before charging with LPG, any moisture should be removed.
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Yeah Iām gonna eventually switch my lid to a 1/2" and go thru killa for a new tank lid. I wanna figure out a quick disconnect situation for the recovery and injection port.
I would like to discuss these two points. My personal experience has been different.
I see on wikipedia that butaneās solubility in water is indeed listed as 61mg/L @ 20C.
61mg of butane is equal to 0.1 ml butane.
That means if you have 1L of water 0.1ml of butane can dissolve in it. IMO for most intents and purposes, including ours, this means butane can be considered insoluble in water. I would also assume the solubility goes way down with the low temps used for extraction. The 0.1ml/L is at 20C. Water would also tend to be frozen at the temps used for extraction and it would be hard to dissolve into the butane/propane.
But weāre more concerned about getting water in our butane stream not butane in our water stream.
Can you automatically invert solvent and solute to say that the opposite is true? Just because 0.1ml (61mg) of butane will dissolve in 1L of water does that also mean the inverse is true, that 61mg of water will dissolve in 1L of butane?
I donāt think it works like that but Iām not a trained chemist and I canāt find any data specifically on waterās solubility in butane but I would bet itās similar to or less than butaneās solubility in water.
To the second point, can you explain a little further the exact way in which excessive water, ostensibly picked up from the material, would make itās way from the collection pot, through the subzero heat exchanger and into the tank?
Here is my thinking:
Even if you invert the data and 61mg (about one droplet) of water became dissolved in each liter of butane flowing over material and into the collection pot, that water would tend to stay with the oil and would likely cause sizzling on the nail before it would have a chance to find its way into the solvent tank.
The conditions in the boiling pool in the collection pot, even with high heat (150F) on the jacket/coil, are still well below the conditions that would evaporate water. For most of recovery with propane conditions are actually below the freezing point for water.
The collection pot is, in this sense, a distillation apparatus whose conditions are such that only the butane āfractionā would boil off and the oil/water fractions would remain in the pot. In other words, the collection pot is a water trap.
IMO if there was so much water getting into the collection pot that it still managed to co-distill with the butane in appreciable quantities, we would have a way bigger problem industry wide with oil sizzling on the nail from the residual water, especially with newer operators, but we donāt have such an issue.
To add a personal story to this: In my early days I once severely over packed a column of fresh frozen material to the point is was very nearly, but not completely clogged.
This required me to significantly increase the temperature on my warm vapor assist tank and also apply the pressure to the column for much, much longer than usual. This caused the fresh frozen to thaw out and some water and water soluble compounds got pushed into my collection pot.
It was a good amount of water, probably at least 20-30ml. The entire mass of water stayed frozen as a nasty ice cube floating around in my collection pot while I recovered because the temp is so low.
I quickly recovered the run, broke down the system and opened the pot. I attempted to remove as much of the still frozen ice as possible with my fingers/tools but enough of it had melted that despite me repeatedly heat purging the oil to death (220F) it still sizzled hopelessly on the nail.
As a final point of contention, if water were indeed able to vaporize out of the collection pot and everyone was picking up significant amounts of water, wouldnāt we also be seeing a lot of condensers picking up water/clogging with ice? I have heard of this issue a couple of times but it doesnāt present itself on the forum with any type of regularity that would lead me to think water pickup is a big problem overall.
I have been running without a dedicated mol sieve for over a year. I regularly run my solvent tank very close to being empty during my runs and I run lots of fresh frozen. I never invert the tank to remove water and Iāve never had an issue with water pickup except the above example from years ago.
Let me know what you think.
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No need to invert the math or whatnot. Graywolfās quote is for the solubility of water IN butane.
61 mg/liter doesnāt sound like very much at all, so it does lead one to wonder how the water in a cls can accumulate to the point where it can freeze and clog injection coils. Either way, this is something that seems to happen, whether the water is dissolved in the butane or not. If there is enough water present to do that, perhaps there is some other mechanism at play.
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To our first issue, you canāt dissolve 61 mg of water in a liter of n Butane. The Vander Waal forces attracting the two molecules not strong enough to break the hydrogen bonds of the water, to allow the alkane molecules between them, so solubility is low.
Water does however get carried along, as evidenced by the accumulation in our tanks. The industries concern about water was borne of hard data from multiple sources and I have flushed water from my own storage tanks, as well as customers.
Consider that the hydrogen bonds are not in play in a vapor state when individual molecules collide and can be attracted to each other by the Vander Waal forces as they move along in a stream.
At a pound a minute recovery rate, passive or active, with a 224:1 vapor to liquid ratio, consider the vapor 238 feet per minute velocity through a Ā½ā tube heat exchanger.
Here are a couple of links I stumbled across in a brief search that might give some insight:
https://digitalcommons.uri.edu/cgi/viewcontent.cgi?article=1057&context=chm_facpubs
https://hemphacker.com/dehydrate-your-butane-and-improve-live-resin-yields/
Note the latter gives water solubility in n-Butane as 3.25 mL per L and n-Propane 3.9 mL/L.
To your second point, a subzero heat exchanger is not a subzero cold trap.
Water sublimates below 0C/32F, which the recovery pot is above during recovery, so an opportunity for water vapor to enter the steam of butane molecules.
Moisture can fall out of solution and still be carried in the gas stream as a cloud or as ice particles unless the velocities are relatively low.
As the process operates on vapor transfer, liquid solubility data doesnāt correlate with regard to potential pickup.
The issue isnāt that the concentrate is sizzling, it is that water accumulates in the bottom of the storage tank and if it get deep enough to be picked up by the dip tube, you can inject a water butane mixture through your column. If it is a carbon steel tank, that water can contain rust, which was the initial problem before stainless storage tanks were readily availableā¦
Inverting and venting or bottom feed stainless tanks is a simple way to address the issue before it accumulates in excess. A bottom bleed valve, even if the tank feed was a dip tube, would work.
Even if there were moisture in the crude, ostensibly the vacuum oven/chamber deals with it, so it shouldnāt be present in the finished product.
A rhetorical question for you.
If you were running enough volume to constantly replenish your tank, had a stainless holding tank so water wasnāt rusty, and you did inject it along with the LPG in the small quantities that it actually accumulates at, versus in a slug, how would you tell looking at the finished product?
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Looks like that is one of my quotes, so mea culpa, my bad, because it is the solubility of butane in water, not verse visa.
Sometimes I have moments of insanity.
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Thank you for the explanation! This makes so much sense. Just like a log doesnāt need to be dissolved by a river to be carried along with the current.
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Sorry for correcting you when you were in fact correct. Props for checking the info yourself. Thatās a good reminder to check facts for ourselves, because even the best of us can get mixed up from time to time.
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as someone running passive, 150lb stock tank in 55gal barrel of dry iceā¦I can attest that water/watersolubles do form at bottom of tankā¦I can see ice at bottom when under vacā¦think <-20c well below boiling point of nbutabe and freezing poi t of waterā¦which are the same conveniently 0cā¦32fā¦ I have a sight glass to observe several processes in this tankā¦ I utilize runs where I dump it fully to clean it out every 3 months or soā¦as far as water trapping goesā¦the dip tube is a good 1/2" to 1" from the bottom so as long as a shit ton of water isnāt allowed to build up , it is always left behind in frozen form as tube socks up last of liquid taneā¦hope that all made senseā¦just chiming in quickly between flipping valves
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Iām a little confused here.
The two above statements seem to be direct contradictions of each other. I also believe you have the statistic in your top statement backwards, rendering it ineffective as evidence that butane picks up water as you are trying to present it.
The solubility statistic given on the butane wiki says 61mg of butane dissolves in 1L of water. Not that 61mg of water dissolves in 1L of butane like your top quoted statement says.
The hemphacker source you give seems like itās a random guyās blog from 2015 that just states the solubility statistics out of nowhere with no direct sources listed like a proper scientific article would have.
I cannot find the 3.25ml or 3.9ml statistics listed anywhere else.
I even checked through the sources the guy listed at the bottom of the article and the Airliquide encyclopedia he lists gives the solubility in water of both butane and propane as negligible. This is in direct opposition to what he says in his article.
Iām not sure about your personal threshold for vetting sources, but I am heavily inclined to disregard this one as Bravo Sierra.
I have also read through the other source you listed.
They are researching a method of estimating the solubility of water in hydrocarbons as a function of temperature. The intro talks about waterās effects on gasoline and jet fuel.
The lightest hydrocarbon they tested was 2,3-Dimethylbutane (C6H14) with a BP of 58C @STP. A significantly heavier/larger molecule than C4H8 butane. Itās solubility of water at 0C given as a mol percentage is .01387.
If you extrapolate this data down to butane/propane at -40C the water solubility would again negligible, wouldnāt it?
Concentrate sizzling would be a byproduct of water accumulating in the tank via the collection pot.
For the water to allegedly get into the tank via the material it would first have to be in the collection pot mixed with the oil as a liquid or solid then distilled out as a gas or carried as small liquid droplets with the gas flow.
The collection pot is, for the most part, well away from the temperature/pressure conditions necessary to evaporate water. Especially for propane, the boiling liquid is actually well below the freezing point of water so distillation would be impossible. Elevated pressure in the pot also raises the BP. I have seen ice cubes in my collection pot before as part of a mistake.
Even if I concede that there is possible co-distillation and whatever other ways it could be marginally possible for water to become liberated from the collection pot, it would not be highly likely that we are removing all or even the majority of the entrained water through these methods. This would cause sizzling.
The threshold for water content to cause sizzling oil is very low, have you experienced this? Sizzling oil would be a much bigger problem than it is now if we were getting appreciable water pickup from material. Can you imagine the issues that would be popping up with new extraction techs running fresh frozen live resin?
Also, most tanks I see in use in extraction today have the diptube extending down to within a couple inches or less from the bottom of the tank so as to make efficient use of the available liquid solvent volume. This would allow issues with water pickup to present themselves much quicker even if the system didnāt run the tankās liquid volume down very low during normal operation.
I know some of the tanks back in the day had much shorter diptubes, like only 3/4 of the way to the bottom of the tank. Iām guessing that thatās why you were having to tip them upside down to vent the water?
My overall point is that if there is appreciable water making it into the collection pot, it is very unlikely we would be distilling it completely or even close to completely out. This would lead to sizzling oil if water pickup from material was significant.
Do you by any chance have a pic of this? Why is the tank under vac?
With a diptube 1" or less from the bottom of the tank I would think you could flush any water just by having the tank at room temp and venting the liquid valve into a safe place, no?
Hey there I donāt have a picture currently but I can try to snap one in the next few daysā¦ The issue issue is having such a close boiling and freezing point respectively, butane does have some water holding capabilityā¦without a molesieve , the solvent always carries some as a vapor back into the tankā¦
I have solvent tank under vacuum conditions due to it being surrounded completely in dry ice lowering Temps to sub boiling pointā¦once nitrogen is vented if psi is possotove at these Temps after an hour plus to settle out, the remaining atmospheric head pressure in tank can be assumed to be nitrogen as butane is liquid at these Temps, and no atmospheric gas mixture has been addedā¦
using a venturi vac pump driven by air compressor (ideally 
) an operator can observe via sight glass when boiling point has been reduced to current (-40ish C) temp conditions and remove that tanks head of nitrogenā¦if that makes senseā¦
all of that being done to reduce back pressure on either a vapor to vaporā¦or vapor to liquid side recovery
ā¦
ā¦as for venting liquid out thereās never more than maybe a few hundred ml over 3 or so month period typically, so couldnāt isolate without dumping the half L or so of solvent that itās sitting in when it is in ice formā¦
sorry if that was ramblyā¦hope it answered question
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Youāve got a Venturi vac but no mol sieve?
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lol that was the (ideally remark) ā¦
A few ādo as the Sop Says and not what the operator truly doesāā¦at play
I do have a mole sieve , it just never got reinterpreted into a larger manifestation of steel orientation a couple years back and hasnāt been to much detriment tankfullyā¦it is something I think about adding back every so often
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Ah, makes more sense. Thatās absolutely the vac to go with for such a task. My new build will be using one
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itās up tgere on my wish list for sureā¦I will say thisā¦a hydrocarbon sniffer doesnāt smell anything off gassing from rotary vane until right up on the exhaust 
wouldnāt recommend it as a full solution but eases some of the worry along with regular oil change
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āIām a little confused here.
The two above statements seem to be direct contradictions of each other. I also believe you have the statistic in your top statement backwards, rendering it ineffective as evidence that butane picks up water as you are trying to present it.
The solubility statistic given on the butane wiki says 61mg of butane dissolves in 1L of water. Not that 61mg of water dissolves in 1L of butane like your top quoted statement says.ā
Perhaps it would be less confusing to you if you read the part of this thread where we already discussed that very same question.
The original question was whether LPG picks up water during extraction, not how much.
It clearly can pickup enough water, or there would be no one experimenting with desiccants, and we wouldnāt be having this discussion.
There would also be no concerns about using carbon steel tanks.
Define negligible?? The ocean is full of negligible mist and drops. I know from personal experience that it can be an issue and designed WolfWurx equipment to deal with it.
Of course concentrate sizzling is a byproduct of water accumulating in the LPG and being injected, if you donāt take it out with subsequent processing. If it is still there after final purge, you have yet another problem with your process.
On the other hand, purging it longer to remove the water doesnāt do kind things to the terpene content, and it leaves water solubles behind, so best to avoid where possible.
With regard to dip tubes, Iāve yet to see one a couple inches from the bottom, with most within fractions of an inch of the bottom and cut at a 45 degree angle.
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