Best way to empty 50L roto

has anybody come up with a table or stand or something to empty out crude from the 50L into a smaller vessel for further processing? it’s kind of a pain in the ass lol

Pain to take the flask off. I just remove the feed input and stick a hose connected to vac and suck it out into a small carboy


Slurp tank is the way to go, any solution that involves pulling the flask off to empty is a recipe for contaminated oil and broken glass, doubly so if you are using mineral oil or any other oil as your thermal fluid

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use a hammer, smash it up, and get a FFE, “best way” imo. :smirk::upside_down_face:


Doesn’t a ffe leave around 5% of your solvent behind and you have to roto the last bit out?

5-10% can be removed in spd, or in a decarbing reactor with attached condenser, with a quickness.

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Depends on how you set your parameters, but I think others as well as BZB (who we bought ours from) are suggesting leaving around 5-10% so you can then pump out that light ethanol/crude mix and not clog your pumps or overload the motors/VFD’s driving them. You also end up having to run clean ethanol through the evaporator side to clean your crude out at days end or between individual batches so you don’t have near-solid crude plugging up the inlet to your pump the following morning after it’s dripped down and cooled down overnight. So in total can definitely be more than 10% depending on how long you run your cleaning cycle and what your parameters are, and you gotta get it out somehow or the guy running the SPD or WFE behind you is going to be pissed.

IMO rotos are but one of many ways to get that last bit out and they’re certainly appealing to a lot of people who outgrew the capacity they could run with their initial investment in rotovaps. They are certainly versatile but with the versatility usually comes shortcomings versus purpose built process equipment. I still think taking the glass off regularly is a poor choice for almost any scale extractor that uses them.


Do you lose much material in transfer with the “slurp tank” method?

you guys empty the flasks? I just disconnect them and sell the crude in the flask as is. its only a couple hundred for a new flask and this way I don’t need to clean it.


Not really, I allow some time for gravity to drain the cone tank, once it slows down to a drip every few seconds I hit the tank with a heat gun to make sure nothing cooled down against the sides of it.