I Need help with a Solvent Delivery Issue

AnselAdams2

New Member
Setup:

Frankie's (nickname for my QP test clp rig) first run went smoothly. I pulled a full vac on the 30# recovery tank and put it on dry ice slurry while I assembled Frankie and moved things outside. I refreshed the vacuum just before I began the solvent wash.

Since this was the first run, the wash was with 5 cans of solvent (420 mil or 2.65 lbs.) and the material column dewaxing jacket had also been filled with dry ice slurry 45 min before the wash.

recovered 2.2 lbs. of solvent into the 30# recovery tank. All good.

Second run. Same setup with a 30# recovery tank on dry ice slurry....
The difference on this run is that i know the solvent tank is about one can short. So i went ahead and flushed one full can as before. When it was empty, i closed the valve and switched over to the recovery tank from the first run that has been sitting in the shed for a week or so. I opened the valve and heard the solvent flowing and verified flow through the sight glass. I also verified by watching the weight climb on the scales.

The problem:
Everything stopped after only just over 1 lb. of solvent had flowed from the solvent tank.

My Resolution:
I finished the run with 2 spare cans of solvent.

Lessons Learned:
What did I F* up?
What if any were my other options to restart the flow?

Thanks in advance.
 

Carolina Dream'n

Well-Known Member
Setup:

Frankie's (nickname for my QP test clp rig) first run went smoothly. I pulled a full vac on the 30# recovery tank and put it on dry ice slurry while I assembled Frankie and moved things outside. I refreshed the vacuum just before I began the solvent wash.

Since this was the first run, the wash was with 5 cans of solvent (420 mil or 2.65 lbs.) and the material column dewaxing jacket had also been filled with dry ice slurry 45 min before the wash.

recovered 2.2 lbs. of solvent into the 30# recovery tank. All good.

Second run. Same setup with a 30# recovery tank on dry ice slurry....
The difference on this run is that i know the solvent tank is about one can short. So i went ahead and flushed one full can as before. When it was empty, i closed the valve and switched over to the recovery tank from the first run that has been sitting in the shed for a week or so. I opened the valve and heard the solvent flowing and verified flow through the sight glass. I also verified by watching the weight climb on the scales.

The problem:
Everything stopped after only just over 1 lb. of solvent had flowed from the solvent tank.

My Resolution:
I finished the run with 2 spare cans of solvent.

Lessons Learned:
What did I F* up?
What if any were my other options to restart the flow?

Thanks in advance.
You've pulled moisture into you collection tank, when it freezes it takes up room/ can clog inlet line.

Whenever your tank is empty after dumping solvent, run nitrogen gas through the tank to remove any moisture/residual gas. Pull a vacuum on tank (using cold trap) right before you start recollecting gas. Tank should already be cold at that point.
 

AnselAdams2

New Member
How did you add the extra cans without allowing atmosphere to enter?
I have an isolation ball valve below the JIC fitting. I make sure the can is depressed before i open the valve. I close the valve before the can runs out of solvent (yes it waste a little). Budget has not allowed me to buy a 50# tank of 99.5% yet, but that is my ultimate goal. Until then I have what I have.

Thanks for your help.

2018-08-12_13-10-15.jpg
 

AnselAdams2

New Member
You've pulled moisture into you collection tank, when it freezes it takes up room/ can clog inlet line.

Whenever your tank is empty after dumping solvent, run nitrogen gas through the tank to remove any moisture/residual gas. Pull a vacuum on tank (using cold trap) right before you start recollecting gas. Tank should already be cold at that point.
Thanks for the feedback!

To your first point. Wouldn't I have had just as much trouble adding the additional cans if the inlet line were blocked as suggested?

To your second regarding running nitrogen through the tank. I like that idea very much. Taking it a step further; it seems i should just add nitrogen after dumping as suggested, but just leave it in the recovery tank that is tagged as "empty" and stored in the shed between runs (vacuum just before next recovery event)? At what psi.?
 

Fadedawg

Well-Known Member
I have an isolation ball valve below the JIC fitting. I make sure the can is depressed before i open the valve. I close the valve before the can runs out of solvent (yes it waste a little). Budget has not allowed me to buy a 50# tank of 99.5% yet, but that is my ultimate goal. Until then I have what I have.

Thanks for your help.

View attachment 4179902
Have you checked your recovery tank for trapped atmosphere?
 
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