From what you’re saying then it sounds like it’s the pump…u said passively worked right?
1 Like
I ended up leaving i was so frustraded. Its a 100# carbon steel tank. 12x24 collection and 24# eco green solvent and trs 21 with a sieve before it. Coliumn not connected
Yes passive worked
Check the lines between the pump and the coil
1 Like
How much pressure was in the coil? Those pumps come with an emergency shut off switch…did it turn off on u at all?
1 Like
Maybe 50 psi when i stopped it. No didnt shut off. But the pressure also never dropped in the coil
What’s up man. I would put the molecular sieve after the pump but before the condenser. Make sure that thing is packed to the T. Your pulls have been probably nuking/sugaring or been a darker color in a significant amount of time. This is bc of the solvent retaining moisture. Unless you’re in a rainforest running the machine I’m betting you’re getting this from the biomass. If this was a slow creeper than it’s your lines.
What’s your RH in the room?
-get a dehydrator or throw the biomass in a oven for a few minutes before your runs. You’re doing this to dry it out. Not decarb. Also have a separate pump pulling while the dry ice/iso is dewaxing your column. Fresh trim retains water. Especially if it’s been in high humidity areas getting trimmed or transported. This is effecting your yields also.
-I’ve had leaks before that wouldn’t show in negative pressurizing only in positive. Just whip out the ppm meter and check all connections in positive.This should be a standard safety check first run of the morning. Make sure you have that room blown down with fans constantly if it’s not in a open space during the run.
Also I’m not sure the size of your system but i ran active typically between 0-15 psi depending on the ambient temperature. I had 7.5 lb column. Lower pressure = lower temperature = better pulls.
Before the coil?
I dont think moisture is the issue. This is brand new gas in an empty coil. Dont really get dark colors really gold actually unless it’s not good trim. Also shatters every time.
Im for sure higher then 15 psi but i use 40 40 20.
The entire sytem has undergone the pressure test treatment. Been at it for the passed week. Theres no leaks in the fittings. The only thing i was even close to questionable about was the pump. Its a 3/8 bore trs21. When XD bored it out idk how well they did it. Even with a shit ton of tape on the fittings they screwed in easy.
In my process in active the PFD went. Recovery tank—>heat exchanger (spiral coil)-> extractor-> wax trap—> pump—-> molecular sieve—> heat exchanger(spiral coil)—> recovery tank. Both my heat exchangers we’re dry ice/denatured alcohol. I might have mistaken when i read that. I apologize. When you shut down the cls do you all valves shut from/to the recovery tank? If this is the case your pump most probably does have leaks. I never broken down your pump before but any gaskets will be degrading from solvents. The pump most probably stops at certain positions?. That’s why you may have not seen it before until now.
XD said that one of the pistons got stuck at the top.
How does that happen and how does that cause this issue?
Possibly solvent vapor pressure. This can be from open lines to your recovery tank? Are y’all closing all valves around the recovery tank after shutdown? Are you going negative psi before you stop your run?
Why not just stick to passive?
We close all valves after. Try to stop at 0 psi but sometimes hit slight vac
Cooling a 100# tank is expensive
1 Like
sounds like you have solvent stuck in your lines. Do y’all have a valve immediately coming out of the collection vessel to the pump? If so right before shut down close that valve. Let it vacuum the rest of the line out. Turn your pump off. Shut valve to the recovery tank. this should all take place in seconds. This will ensure no vapors are left in your lines. Also one last thing i can think of. The coil after the pump has moisture or water build up… the moisture freezes and could cause a ice block in your coil. If these aren’t your issues sell the pump go passive lol.
I’ve got two friends/clients I’m reconstructing for more efficient passive. I’m running one of there labs part time so I’ll get a lot more experience in the passive route. I only ran active but i understand process. Passive is the route to go in theory if you can control ambient temperatures. You don’t need to cool only your recovery tank. Think of it as a relay race with checkpoints that steadily go from hot—-> cold or more energy to less energy. If done correctly it will be more efficient than overall cryo freezing a tank and will get your money back from days with the pump down. Plus passive will make feel better if i step out the lab for a minute. I can’t leave an active running longer than 10 minutes without me wandering is it going to blow up 
How are you doing passive without cooling your collection pot? Nitrogen?
I’m not going to use nitrogen. Nitrogen causes micro cracks in your system. Granted at low temperatures I’m not sure. My plan is to rotate my starting recovery tank and final recovery tank. So I’ll have two tanks to switch from. I’m going open jacket bottom. I’ll cool the collection pod with iso/dry ice than switch over to a insulated candle wax/bee wax/ bucket insulated warmer. I’m still researching the exact one. I’m going to rig this up using the most basic distillation height elevations between my three vessels, two coils, and extraction column. Im not running crc. It’s fresh everything taken down. I’m trying to make this the most efficient way possible to run their system… but I’m sure it won’t be easy as i made it sound. Key to this is valve manipulation. The more I’m thinking of it i might use two collection vessels or a collection chamber than to a separate collection vessel to heat. This would seem more efficient for a faster turn around.
Oh ok so you are cooling your collection also. You mentioned doing passive and only having to cool your recovery tank.
Also micro cracks from n2? This is the first im hearing about this? Have any more info? Why do so many people use it then? I feel like a cls should be able to handle the psi of n2 people use in them no problem
I think you may be confused.
Using LiqN2 to cool things might conceivably cause this.
Using gaseous nitrogen to move your solvent around at 50PSI will not (and that was what @Slabby was asking…).
4 Likes
i apologize for late response i had to deal with some personal matters the last few weeks and needed a break. @cyclopath is correct with N not causing micro cracks. Nitrogen actually helps seal them after i read of researching this. I was mistaken. I do have one thing i hope @cyclopath can share some knowledge and help me understand this better. I know now N doesn’t cause these cracks but after seasonal degradation/ Chinese manufacturing of equipment would the N push open wider the tensile corrosion? I have an article i hope you have some time to review and maybe she’d some light. I know you’re a chemical engineer and have a vast more knowledge on chemical reactions.
Tensile corrosion