Nobody seems to care much about it as long as you’re not actively offgassing enough butane to cause a hazardous situation around the biomass. That seems to be the rule of thumb.
I talked with a guy from Cal Office Of Emergency Services a while back when we were filling out or Hazardous Materials Business Plan, and he didn’t seem to be overly concerned about it. Neither did the fire marshal seem to be concerned as long as it’s not offgassing too excessively and creating a significant hazardous area around the biomass.
Just demonstrate in your procedures that you have protocols in place designed to reduce hazards, like write into your operating procedures that you will recover your tubes to deep vacuum, heat them to X temperature, etc, and write into your procedures things like not storing the spent trim near any ignition sources like space heaters etc, you should be okay.
If you want to be ULTRA safe, dunk your spent trim in water (in a well ventilated area obviously), and the water soaking into the trim will expel any remaining butane out. This will be far more thorough than simply recovering down to deep vacuum under high temp.
The main thing you’ll need to worry about is rendering it unrecognizable and unusable before disposal. Easiest ways are sawdust and a compost mixer, or there are some cheap dyes you can use to stain the material which I believe are also accepted as sufficient.
We are currently operating a type 7 volatile facility in Humboldt.
Thank you for this reply! These tips are killer. Will definitely rewrite our sops to include those processes to further recover any solvent. Are you hooking your heater up to your material column to raise temp and help with recovery, or just on your collection pot?
We extract crude, so we actually soak our tubes under heat for a while, and they are already hot when we dump out the liquid. So when we recover, they are already nice and toasty at about 100-110F. Then we use our master vapor pump and rip all the remaining solvent out and bring it down to deep vacuum for about an hour. We have two MVPs on each unit, so one will recover bulk solvent while the other recovers tubes. The tubes are always done by the time the bulk solvent recovery is done, so it doesn’t really slow us down. We still do back to back to back runs all day long and process 800+lbs a day with two machines.
As a licensed processor in California I can guarantee you heating tube jackets during recovery is industry standard right now.
So heating our material column up to x degrees should help with recovery and make our fire marshal happy. I’ve been extracting a little in Colorado. We’ve never hooked our material column up to heat. But maybe if mr inspector was around it would happen, or maybe rules are different.
At least for CERS we don’t have to say our extracted biomass is hazardous…? thank you for the help.
Unless you call and talk to your fire marshal don’t assume anything. Call them and discuss your process, operating procedures and fail safes. Work closely with all your regulatory folks, communicate often. Make it obvious that you are being transparent and working hard to be compliant. It pays off. We have had several inspections where we were able to leverage our relationships (we do at minimum bi-weekly communications) with the inspectors and heads of those departments to work around/through issues and concerns. Its politics and those who can play that game will have an advantage!