I am part of a group operating a processing facility. We have been operational for a month and have run into an issue during decarb where something is precipitating out forming a sludge at the bottom of the vessel. Wonder is anyone here would have any ideas as to why this is happening.
The crude was made from 8%CBD hemp biomass. 30 gallons of 95% ethanol is chilled to -40c and is used 4 bags of biomass through a Delta Cup30. We do not have a way of keeping the ethanol cold yet and by the time the 4th bag is run, it had warmed up significantly. It is then pushed through a 10 micron sock and 1 micron lenticular filter. The tincture is then run through Delta FFE60 and then put into a EcoChyyl, where the rest of the ethanol is recovered and run through a decarb process in the same vessel. We use vacuum with temp 130c for about 3 hours. When we drain the vessel, there is a significant amount of sludge that formed at the bottom. The crude was tested to have 65% CBD content.
The only thing I can think of is that the warming ethanol is pulling more and more contaminants like carbs that may be cooked during decarb process into a coagulated sludge…
It’s most likely sugars. Usually from extraction with warmer (above -30c) ethanol. Either lower your extraction temp significantly (-60c or below) or simply use the decarb crash out to remove before distillation. Whatever you do don’t add it back and run it in a wiper. I’ve had blades break their welds and shatter the body from sugars going through.
We got 65% CBD with this method from crude. And 79% CBD after one run through BR spinning band. Not bad? We are considering colour remediation for crude and cooling options for the holding tank where the ethanol stays between extractions. I think we will eventually upgrade to a four stage filtration skid. Any recommendations?
No we are not winterizing after decarb. We were hoping that the chilled ethanol would limit the amount of contaminants in the crude. We want to be able to process as fast as possible. Do you think it is needed?
Well I think the answer to this is in this thread.
But to get right to the point, Yes, 100% you need to add winterization as another step, or find a way to keep your biomass below -40 the ENTIRE time its being extracted. once the biomass is removed temps can be warmer.
The dead giveaway is that your oil in the decarb vessel is made up of coagulated crap.
We have the Permacool and it only goes to -40c. The reception tank for the Cup30 is jacketed but I think we need to upgrade it. I was hoping to find a vessel cooled with liquid nitrogen instead of getting a chiller type. The hope is to keep the temp low to do multiple passes with the same ethanol. Still researching this.
Be careful doing this as most stainless steel is only pressure rated down to -20F or so. Obviously this is a non issue if your equipment doesn’t operate under pressure.
The membranes @MagisterChemist is talking about are selective filtration membranes that can separate ethanol from your plant tincture mechanically instead of with heat.
I recommend a sanitary tube and shell. Not because they’re efficient, just that it’s really easy to deal with clogs if a bag rips. Which isn’t true of flat plate HX.
Figuring out how to catch anything that makes it out of the fuge that might not be good for the pump (like zippers), or the spray heads (cannabis?) is also a required part of this trick.
