Refrigerant recovery cylinders

Because a lot of folks are using these to store butane in, I figured I would start this thread instead of asking people in pm's and other threads.

I have a couple questions that are fairly basic, I just want to make sure I am using it safely before I start.

Ok, so for those of you who don't know what these look like, here is a picture:


I know the red valve is for gas output, and the blue for liquid, as it says so right on it. I know the liquid one means it is drawn out of dip tube, ensuring liquid does indeed flow out.

My questions are:
- Can I fill the RRC passively-- i.e. with the use of temperature manipulation instead of a vacuum pump? If I freeze my recovery cylinder, and warm up my output vessel, the liquid should flow freely, no?

-If so, do I need to use the liquid valve when putting liquid into the tank? It seems like it wouldn't really matter for input, as I fill my recovery tank for my Tami this way, and it has no syphon in it.

-I took the advice of banana buds, and picked up a refrigerant charging hose. With the use of a 1/4" male flare > 1/4" male NPT adapter, I easily can attach a quick disconnect nipple or coupler to it. Thanks!
Question is--
What are these hoses made of? neoprene? I can't seem to find any info on them.
This is a PDF from the manufacturer of my hoses: http://www.thermalengineeringcompany.com/pdf/thermal-hoses.pdf

You can certainly fill them without a pump.
A scale is needed in either case though. Weigh the tank empty and write the empty weight on the tank where it can't get rubbed off.
Freeze the tank, and fill through the vapor port. That way if the gas pressures in both tanks equalize gas bubbles can migrate to the supply tank and liquid can flow.
The primary thing driving the liquid to the fill tank is the greater gas pressure in the supply tank dead space. Heating the supply tank with hot water will help.

I set the supply tank upside down elevated from the tank to be filled. Best thing is to place the fill tank on a bathroom scale so you can check the weight.

Make sure you calculate the weight of your fill.

Example: a 30lb. recovery tank has a volume of 11.9liters, so max safe fill is 9.5 liters or 5.7kg. You can go a bit over, the 80% rule is for a worst case scenario but if the tank is going to be stored I'd stick to 80%. Double check your calculations...

Make sure you weigh the tank empty, the catalog tares are off sometimes.

Another important point is to pull max vacuum on the recovery tank before you start to fill. This ensures you have as little oxygen as possible in the tank and speeds up filling.

One note before you use a new cylinder, flush it out a few times. New cylinders can have traces of oil from manufacturing in them.

Add a small amount of butane, shake, rattle and roll to dissolve anything on the inside. Then tip it upside down and open the vapor valve to drain the (possibly) dirty liquid.
Rinse, repeat and wipe hands on your pants...

Don't vent it upright through the liquid port as the dip tube won't suck up all the liquid. Upside down through the vapor valve ensures any crap in the tank gets expelled.

RB

Thanks for the reply the Ricky!
Still need a bit of clarification however.

Rickys bong said:

You can certainly fill them without a pump.

Click to expand...

Rickys bong said:

Another important point is to pull max vacuum on the recovery tank before you start to fill. This ensures you have as little oxygen as possible in the tank and speeds up filling.
A scale is needed in either case though. Weigh the tank empty and write the empty weight on the tank where it can't get rubbed off.
Freeze the tank, and fill through the vapor port. That way if the gas pressures in both tanks equalize gas bubbles can migrate to the supply tank and liquid can flow.

Click to expand...

How would one go about achieving max vacuum without a pump? I guess this is what I was referring to when I asked if a pump was necessary. Does freezing the cylinder really achieve a full vac? I understand the scale is necessary, as I have been utilizing butane recovery for quite a bit now. I know it will work if I just use temp. differential, but if a pump is necessary to pull a vacuum on the empty cylinder first, that is good to know. I plan on acquiring one soon for vac purging anyway. Since I won't actually be pumping liquid butane through my vac, I don't really need to go big like y'all using the Apion G5 correct? I'm thinking a standard 1 or 2 stage vacuum pump will be adequate.

Rickys bong said:

One note before you use a new cylinder, flush it out a few times. New cylinders can have traces of oil from manufacturing in them.

Add a small amount of butane, shake, rattle and roll to dissolve anything on the inside. Then tip it upside down and open the vapor valve to drain the (possibly) dirty liquid.
Rinse, repeat and wipe hands on your pants...

Don't vent it upright through the liquid port as the dip tube won't suck up all the liquid. Upside down through the vapor valve ensures any crap in the tank gets expelled.

RB

Click to expand...

Good to know about flushing the cylinder. Will do.

ahhhhhh... sorry fer the confusion.

I thought you were referring to using a recovery pump to pull the vapor from one tank and pump the compressed/condensed liquid into the smaller recovery tank. I should read more carefully...

You really don't need to pull a vacuum but with a new tank getting rid of any air is important. Two ways to do this, either with a recovery pump or any vacuum pump that will get a good vacuum.

The other way would be to fill a bit of butane into the tank, just a tiny amount of liquid, 50mls or less. Put the tank in some hot water and purge off the vapor. Do this a few times to purge the air out. Not really a good method but it'll work.

If your recovery tank has been purged of air and all that's inside it is butane vapor then freezing the tank will drop the pressure close to zero, and a vacuum pump won't help much.

Maintaining a pressure differential is the important part.

RB

Trichgnomes said:

How would one go about achieving max vacuum without a pump? I guess this is what I was referring to when I asked if a pump was necessary. Does freezing the cylinder really achieve a full vac? .

Click to expand...

What RB said.

We use two different pumps. A high vacuum two stage rotary vane pump and a G-5 refrigerant recovery pump.

You can pull a vacuum with Cryo=pumping , which works on the principle of Boyles Law: See a Boyles law calculator at http://www.1728.org/boyle.htm.

You could drop the gas pressure to rough vacuum levels if you got it cold enough. At zero Kelvin, you would have no gas pressure, but you would still have oxygen in a flammable gas tank.

Consider having a refrigeration repair shop pull a vacuum for you, if you want to save the cost of the high vacuum pump.

THOSE TANKS ARE SO DIRTY!!!! Im trying to get mine clean but im having no luck really.

Ive ran 4 distillation runs threw my machine and every time its dirty as hell.

Im going to try the upside down trick because i know the dip tube isnt getting it all out for sure.

If i were you i would seriously look into building a tank from a spool that is all stainless steel rather than waste money on those. They have brass parts too which im not too into.

As far as the pump. You will need a vacuum pump to pull the cylinder to a full vacuum. The pumps are around $100 to $150 and you can get one from harborfreight or amazon. a 3 cfm will work fine.

Here is how i run passive.

Hook up your recovery tank and supply tank to your extractor.

Hook up the vacuum pump to the extractor and turn the pump on.

Open the vac line valve and both ball valves to the tanks and pull a vac on the extractor, the recovery tank and the line between the supply tank. (supply tank is always closed untill your ready to run) this will get all the atmosphere out of the entire system. NOTE: The recovery tank line goes into the vapor side of the recovery cylinder and the supply tank line goes in the liquid port of the solvent tank.

Once your gauge reads 29.9 or 30 and the pump stops gurgling and starts to run smooth you can now close off the recovery cylinder vapor valve, then the recovery ball valve then the supply ball valve and then turn off the vacuum pump. NOTE: Never turn off the pump then close the valves, you might suck all the oil out of your vacuum pump into your machine.....

Now put your recovery cylinder in a gatorade style cooler (like the football players dump on the coach after a win) and fill the space around the cylinder with dry ice. This should bring the tank down to -50* and now your ready to distill some butane or do a run.

Now just open the liquid port on the solvent tank and then the ball valve to the machine. You will now hear and see if you have a sight glass liquid flowing threw the column into the collection pot. Put the extractor on a ice bath and gently warm up the solvent tank.

Once you have put the desired amount of butane into your collection pot valve off the ball valve and liquid port. Move the extractor into a 80* to 90* water bath and open the return line ball valve then the vapor port on the recovery cylinder all the way (dont just crack it it needs to be totally open to not leak potentially) you will now hear thhe gas returning to the cylinder rapidly. Your pressure gauge should be around 10 to 15psi if the water is warm and 6 psi in cold water. Not much pressure but thats kind of why this is not very dangerous if done correctly. (for reference a beer tap flows at 5 psi) cheers.

So after about 1 our your gauge will drop to 0 or even go into a slight vacuum. If your distilling you want to watch that gauge carefully and not pull a vac or you might boil off the pentane your trying to distill out. If you go over 96* you will also boil off the pentane so watch that warm water bath temp real close. Its much easier to remove pentane from butane than from oil.

Now carefully unhook all the hoses and vent off any trapped gas.

Weigh your recovery cylinder. Does it have roughly the same amount of butane as your target weigt in the extractor? You might loose a few ounces if any during the recovery.

Now open up the machine and check out the surprise inside!!!!! If your distilling clean it real good and do another run. Keep doing runs untill you can not wipe anything from the machine.

Now your system is clean and ready to do a run.

To do a run of material just do tis exactly the same but put the material column on the machine. I distill without the column because its easier to move it around since my column is giant.

Hope that helps.

Gray Wolf said:

Consider having a refrigeration repair shop pull a vacuum for you, if you want to save the cost of the high vacuum pump.

Click to expand...

Os there a simple excuse as to why i would be doing this should the question arise?

Spooky ghosts in this thread its so old...

Os there a simple excuse as to why i would be doing this should the question arise?

Click to expand...

Pretty standard procedure to have done on a refrigerant recovery tank. I guess my question if you asked me to pull a vacuum on one is why you have a refrigerant recovery tank and no vacuum pump.

pay to play

pay to play

You should just buy the right equipment to do the job imho. This is a professionals game if not taking seriously dumb asses blow themselves up.

100 lb Manchester tank

100 lb Manchester tank

Greetings all,

I'm just ordering new, larger recovery tanks. I just want to confirm I am ordering the proper ones.

100 lb Manchester HVAC, dual ported recovery cylinder with 3/4" fitting? Are there any other pertinent ordering details I am missing?

Thank you kindly!

OregonKushFarm said:

THOSE TANKS ARE SO DIRTY!!!! Im trying to get mine clean but im having no luck really.

Click to expand...

Is it a re-furbished tank? The re-furbs are way cheaper and a lot of busy HVAC shops stock only these for that very reason. They are not pretty inside and should not be used.

Best Value Vacs is sourcing stainless lp bottles. they look kewl

I wouldn't get one of the BVV tanks, they arnt the best quality from what ive heard. Theres a guy james dellay on Facebook who is ordering tanks made in china and so far everyone has been happy. Im about to buy one of the bigger SS ones to replace my 100# Manchester.

MrSpectre said:

http://wenzhoukst.en.alibaba.com/pr..._MNPT_threads_siphon_tube_to_tank_bottom.html

Click to expand...

Keep spool diameters small enough for 3x the working pressure. The larger the diameter the less pressure the triclamp gasket will hold. Also be wary of long term storage with triclamps. The clamping system is not appropriate for long term storage and it will not meet DOT standards for storage tanks.

The gasket/clamp joint is the weak point. Flat end caps hold more pressure than the gaskets already.

https://instagram.com/p/2R-tmggp8X/?taken-by=bestvaluevacs

Supposedly the BVV tank will be rated to 400 PSI and be fitted with blow out valves, all SS. They are gonna be round $400, and a month away at the earliest. They said they are launching a full scale SS supply biz for the BHO, brewing and auto market. I spoke w Adam this morning...I gotta say I hope they give glacier tank a run for their money, I am getting very wary of going through the backorder game, even when I order stuff they say is in stock! ��

^^^now I hope that works out, but in the meantime I was hoping for some advice about my spool tank...

I've built a Lil terp style system, for now just using a 6" welded bottom spool for my recovery tank. I'm using high pressure clamps torqued to 20 ft lbs all around, and envelope gaskets. I've pressure and vacuum tested for days....it holds. If I store my tank outside, completely out of harms way, will that be ok for storage between runs? I've put so much effort into making this system with the most suitable high purity materials I know of, storing my solvent in a possibly dirty carbon steel brass fitting tank is something I just do not want. I see sweet leaf owners using spool tanks, anybody know of any issues?

Eh, I'll probably bite the bullet and get a damn recovery tank. I see all you pros using them, if you guys tell me I should I will. I just really wish they could be opened up for cleaning and inspection.

Everyone would prefer stainless. You can keep steel tanks clean and dry- that is the trick if you use them. Use water traps, molecular sieves and turn tank over to flush out water everyday. Wash a new tank with butane with several rinses to clean it. Steel tanks are a pain but they can be kept clean.

6" would be tons better than even 8" if you are going to make a spool tank. Use a flexible gasket like a envelope type. Pure or filled PTFE will not hold seal over long term storage. Keep it out of the sun if stored outside. Check out pressure tables for 150 F since items often get that hot when stored outside.

dont know to much about fittings but was wondering if this would help fill/recovery times being 1/2 vs 1/4 ? or the inner diameters the same? http://www.centurytool.net/Refrigerant_Tank_1_2_ACME_Y_Valve_Assembly_R134A_p/y-valve acme.htm

mang305 said:

dont know to much about fittings but was wondering if this would help fill/recovery times being 1/2 vs 1/4 ? or the inner diameters the same? http://www.centurytool.net/Refrigerant_Tank_1_2_ACME_Y_Valve_Assembly_R134A_p/y-valve acme.htm

Click to expand...

We use a 3/4" tank valve.