The search for a proper recovery pump..

[rb extractors]

Was talking with Yellow Jacket yesterday about a new recovery pump that is coming out to compete with the appion G5 on speed and price. Anyway, they are coming out with a butane compliant pump for use in europe where it is more popular to use butane as a refrigerant.

The down side is that it will more than likely be an oilled design. I asked if they might know of something that would provide a way to filter the exhaust so that there was no chance of crankcase oil getting mixed with the butane.

 

[Gray Wolf]

Was talking with Yellow Jacket yesterday about a new recovery pump that is coming out to compete with the appion G5 on speed and price. Anyway, they are coming out with a butane compliant pump for use in europe where it is more popular to use butane as a refrigerant.

The down side is that it will more than likely be an oilled design. I asked if they might know of something that would provide a way to filter the exhaust so that there was no chance of crankcase oil getting mixed with the butane.

Non oil-less designs typically come with and oil separator, but they aren't 100%.

Hee, hee, hee, My two Gast diaphragm pumps arrived yesterday, so we will be experimenting with Plan B.

As previously noted, Plan B involves using the diaphragm pump to recover the butane to a auxilary low pressure tank, and the Appion to move it from the low pressure tank, to the recovery tank. This will prevent the Appion from ever running "dry."

We will also try it using cryogenics to chill the storage tank, so that it isn't under much pressure, which may also work and eliminate the need for a second pump.

 

[rb extractors]

I wonder if there is something that would give us as close to 100% as possible?

Hopefully the gasts work out!

 

[icdog]

Are the gasts electric pumps?

 

[Gray Wolf]

Are the gasts electric pumps?

1/2 horse 120VAC

 

[icdog]

I somewhat get that Gast pump idea now. Is there any reason why it wouldn't work? How much was it?

 

[Gray Wolf]

I've just blown $1200 if it doesn't work, but don't see why it won't. We'll soon see.

Around $600 with shipping.

 

[Breakover]

I've just blown $1200 if it doesn't work, but don't see why it won't. We'll soon see.

Around $600 with shipping.

How is that Haskel working out? Is it as fast as you expected? How is the noise level?

 

[rb extractors]

I've heard it works nice but is inefficient given the amount of power required versus recovery times. Plus, it won't work for the majority of us :/

 

[C'Ya]

Nice GW those should work well, I'd suggest larger diameter line on exhaust side to reduce pressure before the after cooler and maybe adding extra tank so pressure goes in vapor side pushing liquid over to primary tank that should help some with diaphragm's pressure limits.
I was considering KNF Explosion Proof Motor Vacuum Pump, it's hazardous location rated and PVDF/SS/PTFE construction should make it well suited, but figured I'd wait and see how your tests went first, and also waiting for the money tree to grow new leaves.
Also have been looking at cryo coolers for rapid chilling the solvent, so can't wait to see where you go with that, a helium compressor and cold end should work well beyond our cooling needs.
Thanks
C'Ya

 

[Gray Wolf]

How is that Haskel working out? Is it as fast as you expected? How is the noise level?

Works slick, but no runs to compare speed. The Mk IV that I purchased the first one for, went out the door so fast, that I never got to do side by side comparisons.

They are larger displacement pumps, moving slower, and don't heat up the butane as much, but are too loud to stand beside without ear protection and do require 40 scfm of clean air, which is about a 10 horse screw compressor.

You can plumb the exhaust elsewhere and muffle it, and Eaton makes a single phase 10 hp screw compressor/refrigerative drier/receiver combo that I've seen advertized at around $7K.

Two more Mk V systems with Haskels underway, so I'll try to get a direct comparison to the dual Promax 6000's that the customer is currently using.

 

[icdog]

Hey GW did you get a chance to test the gast yet?

 

[Gray Wolf]

Hey GW did you get a chance to test the gast yet?

Working on it. Have all the parts except the pressure switch, which is due Monday.

Besides the new builds underway, we started updating the original Mk V prototype yesterday and are and adding that feature as well.

Yesterday we upgraded the dual columns from 24", to 36" and added the top flush feature. Today I'll add the axillary tank plumbing to accommodate a pressure gauge and adjustable pressure switch.

The twin cylinders have separate intakes and exhausts, so the DAA-501P GB can be used to simultaneously evacuate the column and the pot separately.

 

[icdog]

GW whats the pressure switch you mentioned? Is it for using the Gast?

Is the layout for the Gast - terp gast 50lb tank appion 100lb tank?
If thats right how does this all work while doing floods? Do you flood from the 100lb tank, recovery with gast into the 50 lb tank and then with the appion into the 100lb tank at the same time?

Why can't the Gast do it all?

 

[Gray Wolf]

GW whats the pressure switch you mentioned? Is it for using the Gast?

Is the layout for the Gast - terp gast 50lb tank appion 100lb tank?
If thats right how does this all work while doing floods? Do you flood from the 100lb tank, recovery with gast into the 50 lb tank and then with the appion into the 100lb tank at the same time?

Why can't the Gast do it all?

I'm mounting an adjustable pressure switch in the float switch port of a 50# recovery tank, and will experiment with pressure, in the range of 15 to 30 psi.

The switch turns the oil less recovery pump on and off, with the Gast running constantly.

Correct sequence, and flooding is from the 100 lb tank.

The Gast may do it all, if the 100 lb tank pressure is low enough, but diaphram pumps are limited on how much pressure differential they will tolerate on opposite sides of the diaphragm.

They are good for about 4 bar, and will pull ~26" Hg vacuum, or put out ~60 psig pressure on the output side, but not both at the same time.

We will try adding a subzero heat exchanger, as well as alcohol and dry ice for the recovery tank, at which pressure it might work all by its lonesome.

 

[Gray Wolf]

Hee, hee, hee, snicker, snark, snort, awhoooooooooooooooooooooooo!!!!!!!

We installed one of the Gast pumps on the beta manual MkV-2, along with a 50# holding tank and pressure switch, followed by a Promax 6000, and have had a day of running it on product.

A few key points at this stage of development.

The first is that it works.

The second is that it is about three times as fast as dual Appions or dual CPS TR-21's.

It also pulls the pot of liquid under deeper vacuum faster, requiring more heat to keep the lower tank from forming block ice. The 2W/in2 silicone heat mat can't keep up, so will experiment with a 5W/in2 unit.

We had to relocate the lower thermocouple to the upper part of the pot, because even set on 85F, it was heating the upper portion of the pot to 140F.

The Promax 6000 is the loudest pump yet. We thought it was broken, but pulled another out of the box new and it was just as loud.

The Gast is whisper quiet.

Lastly and the challenge; starting the Gast pump under pressure, sudden changes in pressure, or sudden current spikes from starting other motors knock the 1/2 hp Gast pump off line, requiring a restart.

We got rid of the voltage spikes by adding another circuit, and are working on resolutions for the pressure issues.

I think with a few more engineering tweaks, that we will have a weaner. Certainly the reduction of wear and tear on the oil less recovery pumps and the 3 X speed are good reasons to look for resolutions. More as it unfolds.

 

[icdog]

Great news GW. Does this mean we might not need a 50lb and a 100lb or an apion, the gast will do it all?

Could you clarify what you meant by pressure changes and a restart? When you start a run from a -29 vac does the pressure increase from a flood turn the gast off?
Is it a big deal to do a restart?

 

[Gray Wolf]

Great news GW. Does this mean we might not need a 50lb and a 100lb or an apion, the gast will do it all?

Could you clarify what you meant by pressure changes and a restart? When you start a run from a -29 vac does the pressure increase from a flood turn the gast off?
Is it a big deal to do a restart?

We have yet to run any experiments with dry ice, to see if we could eliminate the 50# auxillary tank and oil less secondary recovery pump. One step at a time.

A pressure change when certain valves are switched suddenly stalls the pump and kicks its thermal overload. You have to cool down the Gast pump's thermal overload, adjust pressures, and turn back on.

The motor is 1/2 horse and has a capacitor to soften the start, but still pulls a lot of amps starting up and when there is a high vacuum on one side and pressure on the other side of the diaphragms.

We relieved the vacuum by injecting a brief shot of butane and the pressure in the axillary tank by continuing to run the Promax 6000 until it caught up.

 

[rb extractors]

this is amazing news!

 

[icdog]

Is the Gast made to run with butane, or capable of dealing with it better then the G5?