How big is your biggest extractor?
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passive is as fast as your pipe aperture.
a piston or a rotary vane or a diaphragm just get in the way. the gas knows where it wants to be based on temperature and pressure.
one of our large condensers can burn(sublimate!) 2tons of dry ice in a day, and i know it is faster than any compression pump recovery unit.
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I weigh about 180lbs.
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Lololol
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Hahaahaaha
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Passive is not necessarily faster than active, itās about vapor generation in the collection pot/evaporator and how the system is setup and operated as a whole.
If youāre using an ideal example of two tube-in-shells to evap and condense, powering them is no object, and youāre only interested in fast recovery rate and not overall system work flow Iād say that passive offers the most direct route to the fastest recovery rate possible. You definitely could take the same setup and get a large enough pump from the oil and gas industry like a corken or blackmer and hook it up to the tube-in-shell evaporator and it would recover at the same rate as the passive setup because the vapor generation is still the same.
Iām guessing you did not use an adequate pump setup on your attempts to go active. Also, Titan Extraction claims to be doing 3lb/min butane active recovery. They arenāt saying which pump, but it sounds like itās probably a blackmer or corken.
Is your friend running for crude or dabbing oil passively at 3lb/min? Is he running cold solvent? To me the achievement your friend has made is to vaporize 3lb/min of butane because that is what dictates recovery speed, being active or passive is moot.
I will admit that the pump selection options are pretty dismal right now, especially for small hobbyist level systems. Getting a real active setup requires spending around $10-20k.
The CMEP-OL has terribly low displacement at 1.25CFM for what it costs. Also, the CMEP-OL uses a non-articulating piston design and has a very weak piston ring design. The manufacturer even recommends replacing the piston rings every 6 months, thatās pretty terrible. This pump was rushed to market around 2015 and IMO is a terrible option for the cost. CMEP piston/rods
The TR21 also has low displacement (no spec found) but has an articulating piston and a much better piston ring design. These are what I currently use and I have had good reliability from them. TR21 piston/rods
To get decent recovery rate, in line with what passive would do on a similar system, multiple TR21ās or CMEPās are usually needed.
CMEP and TR21 seem to be the most popular, and cheapest, options out there. Pumps like the GC5000 (Blackmer), PDX Gold, Haskel and MVP offer much better performance but are a step up from the hobbyist level and require the rest of the system be designed to support them. You canāt just hook a GC5000 up to an 8" collection pot with a 2kw heater and expect to get better results than a CMEP-OL or passive.
I guess one of the main points Iām trying to make is that itās about overall system work flow and design, not just achieving the fastest possible recovery rate.
In a passive system, how would you apply pressure assist to the solvent tank to inject a new column while simultaneously recovering from the collection pot?
It sounds like you would need to inject one column into the collection pot and recover it completely before starting to inject the next column. That sounds like a hindrance to overall system work flow that would require more chilled tanks and overall more complication to remedy versus an active system where the pump can deal with backpressure on the solvent tank while recovering at the same time.
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Your recovery tank is creating a negative pressure. Therefore sucking the next column in line and can be run continually. I started off passive and felt pumps were the way to go. After lots of money spent and dealing with leaks. Let alone the sound of a pump running for 8 hours and the electricity. I removed them and got recovery speeds I could only wish for! I can also improve the speed with inexpensive upgrades vs a pump set up was always causing problems . All around passive is the way to go for me running 1 column or 100
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Passive is significantly faster than active.
All of the rest about recovering at the same time as injection, you can still do if you have the correct setup. I can show you a picture of one and describe how it goes. I really donāt want to have to, quite honestly.
Yes passive is faster. Pumps canāt beat thermodynamics.
So, does titan have a video of what pump and setup will achieve this lustrous 3lb a min. What temp is their recovery, is their tank empty and at negative pressure, being itās maiden voyage.
He was running crude and probably only about 120f. When I push 120f. Iāll push 2lbs a min, easy. I can grab a video of this lustrous 3lb a min from two different passive guys I know. You can also follow my screen name and see my recovery videos.
What pumps (plural) can keep up with passive? I havenāt seen it. The amount of driving force that pump needs to be faster than the latter. Isnāt even worth spending the money to prove a point.
Having the right pump for the system will absolutely help you recover, āefficientlyā I guess, but it doesnāt change that I can dial in a system and it will recover faster than a pump in its place.
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You canāt just compare āactiveā vs āpassiveā. There are multiple factors to ultimately consider (which have already been touched on):
- Solvent recovery rate (aka power transferred to system)
- Ancillary equipment power consumption (thus, cost of operation)
- Equipment dimensions
- Time & cost of maintenance
Maybe youād need an algorithm, based on importance, to really figure it outš. Iām assuming certain variables are standard across the board (e.g. required end product).
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hey dred, been wanting to pick your brain on this for a while now, I read online some time ago that passive is not ideal due to lack of turbulence created from the pump causing your driers to not work how they should. Iāve seen such great results from you and others though that seem to show otherwise. Do you have any experience in this regard or is it just an opinionated piece?
Iām all for passive, it works great in my experience, but just want to understand more of the science behind it.
The uses of recovery pumps are so important to this feature because they create a oscillating effect with the flow of the gas. This minuscule and split second where the gas technically stops and sits in the void is the theory where desiccant beads actually work.
This is why we do not like passive when it comes to cleaning hydrocarbons, and managing the purity and moisture content. We prefer pumps because they act as regulator in the process.
(source: Closed Loop Extractor 101 : The Basics | Summit Research)
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I disagree with this theory
Passive is the best if equipment allows the dynamics of gasses is a fairly simple on and so are sieves
One can make things as complex as one wishes but passive once set has very few hassels
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molsiv works fine with the turbulence around the beads. why create pauses in flow with a pump?
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Think I saw your dude on IG pulling 3lbs/min. Badass and makes me want to sell my MVP and set up to ādowngradeā ā¦ passive is kickass.
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@Dred_pirate you must have missed this sentence from my response above. If powering (both hot and cold) a pair of tube-in-shells is no object I would agree that that is probably the fastest way to transfer butane purely via evaporation and condensation. You could also use a tube-in-shell evaporator with a properly sized gas compressor to make an equally fast active setup. Whether active or passive, itās all about the vapor generation.
Once you want to apply the idea to a high throughput, larger scale batch extraction system where simply dunking the supply tank in a DI slurry is not an effective or economical option, things change. You start needing large, expensive jacketed or double jacketed tanks, high capacity chillers and/or micro-bulk levels of LCO2 or DI to get the cooling exactly where it will be most effective on the recovery side. When they need to clear the butane vapor from a rail car there are probably several reasons they use a compressor and not a tube-in-shell/chiller to get it done.
Iāll agree that given the very shitty options for smaller pumps, namely CMEPOL and TR21, itās no surprise to me that people who are not well versed in sizing pumps for specific applications would falsely think they can put a single CMEP or TR21 on their system and be faster than passive. That is why Iām not surprised a lot of people who are small scale switch methods from active to passive with better results, in a lot of cases the pump is undersized and creates a bottleneck.
Both those pumps, CMEP and TR21, really are terrible options and it usually requires 3-4 of them (or more) to handle a 12" recovery pot w/ propane mix, IME. Lots of pumps out there could keep up with your passive vapor generation rate of 2-3lb/min butane, I think that would be around 14 cubic feet of vapor per minute. Iām pretty sure a GC5000 (maybe), Blackmer, PDX Gold or the new 18CFM MVP could keep up with that. Those are expensive pumps though and I understand in some cases and scales of operation the passive route could make more sense and itās easier to just dunk the 50# tank in DI/alcohol.
My major point here is that a passive system works based on pressure/temperature gradient and therefore cannot work with significant back pressure on the recovery side. This presents issues with regard to pressure assisting, system workflow, and equipment needed to scale up beyond hobby level.
The fact that the entire mass of solvent on the recovery side has to be kept at very low vapor pressure so as to no impede recovery really seems to be a big thorn in the side of passive recovery, IMO. Especially if you want to start running propane mixes or pure propane. A chiller with a large cooling capacity at 0C for butane is much cheaper than one with large capacity at -40C or lower for propane.
I think being able to inject while recovering is an important aspect of an extraction system. If you ever feel like explaining it, please do. It sounds like it must add to the overall complication of a passive system.
recovery pumps are a crutch for poorly designed systems.
significant pressure on recovery side is generally due to the heat of compression which you eliminate with cooling the same as a passive system.
the pumps that keep up with hundreds into thousands of cfm of gas compression are much much much much more expensive than tubes and cold.
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Long story short. I donāt dunk anythingā¦
Iām busy at work and donāt have the time to rebut.
Get a gc5000 and I bet it wonāt keep up with me after I change a couple things, and lower my recovery temperature.
For the price of continuous maintenance on a pump. They still arenāt worth it.
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This is a cool thread, IME having your system set up for active recovery is a bit more user friendly for people with less of an understanding of thermodynamics. Itās takes a bit more know how to run a passive system efficiently but when done right will crush an active system. We currently process upwards of 60lbs per day working 8-10 hours while recovering about 360lbs of solvent on an passive system and have upgrades coming soon that will massively expand our capabilities. We definitely arenāt the biggest out there but for non-hemp extraction I think we put up some good numbers
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I think recovery pumps allow for simpler system design and operation. Remember, Iām talking about multiple batches of quality dabbing oil, not continuous crude production.
In my system, significant pressure of about 50-70 PSIG on the recovery side comes from pressure assisting to flood columns while simultaneously recovering. This is exasperated by the addition of CRC filtering to the process which requires an extended period (over several minutes) of high pressure on the recovery side to facilitate fluid flow through the filter bed.
How do you deal with this in your passive systems?
Also, my recovery side pressure will see a slow increase to around 20 PSIG as the liquid level in recovery the tank rises. This is no problem because I have a pump that can work against pressure. There is no need to chill the entire mass of solvent on the recovery side to lower vapor pressure. I have no mechanical chiller anywhere in my system.
Heat of compression in my current system adds about 40F to the gas stream which translates to only needing about 15.6 Btu/lb to counteract (40F X .39 Btu/lb/F). Compared to the energy removal needed for phase change, its not super significant.
Here is a link to a new surplus Corken T891 with 128 CFM listed for $24,500. Thatās way more than enough CFM for the current state of the industry and at a very reasonable price. Corken T891
@Dred_pirate Yea, the capacity of the GC5000 is questionable, especially for the price they charge, thatās why I put the ā(maybe)ā after it in my list.
Also, Iām not sure about pumps needing continuous maintenance. If youāre talking about the disaster that is the CMEPOL with the greased bearings and shitty piston design I understand, but the other pumps like Haskel, PDX Gold, Blackmer/Corken etc. are very low maintenance and are designed for heavy use.
Iām not sure about you, but I have way more trouble with low temperature chillers needing maintenance and having issues than positive displacement gas pumps. Didnāt you have your chiller get knocked off-line not long ago?
@WarrenB Can you elaborate on what you mean when you say a proper passive system will ācrushā an active one?
Just out of plain old curiosity because you said āweā, how many people do you have working to get through 60lbs in 8-10 hours?
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@Tech1145 weāve used the Haskell pumps before and definitely had to rebuild more then once a year like they claim. Iām a little confused by what your saying about high pressures but if your saying what I think you are then the answer is nitrogen pressure assistance. We constantly scrub our head space in the recovery tank to remove the nitrogen during recovery. This flow aids in pulling the liquid solvent building up in the condenser into the recovery tank via siphon. Iām sure we lose a small amount of hydrocarbon vapor that may be in the headspace but with the cold liquid solvent coming in and chilling the tank our tank is always sitting at a vacuum during recovery so any vapor loss is minimal.
For your question on how many people we have in our operation, Itās just me and my partner who run the extraction equipment, however we have a crew for packaging, traceability, HR, and sales.
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