Vacuum systems for getting rid of spent biomass

Looking at buying an NSEP/Bock 755, which can hold about 100 lbs of biomass

Curious if anyone is making vacuum systems catered to our industry? I’m sort of familiar with what the woodworkers use, but interested to know if anyone has done experiments on what kind of velocity and what not are necessary to use a cyclonic separator with hammer-milled spent biomass?

I really don’t want to have to shovel a horizontal centrifuge full of dry cake empty just to turn around and do it again several times a day, and then have to take an explosion proof shop vac sized unit to get the smaller bits of cake removed that I couldn’t get with a shovel or scooper.

I’m also curious to know if anyone’s thought about or devised an airtex/rotolok type system for continuous emptying of a material hopper or cyclonic separator in our application. Thinking about how nice it would be to just be able to have it run all day and fill up totes with the tops routed off instead of filling up and forcing a shutdown/cleanout…

would you be looking at just drying the biomass so its doesnt have residual solvent?

The Bock/NSEP 755 is a centrifuge to remove as much as possible of the solvent from the biomass. I’m interested in a more elegant solution than a couple of guys with shovels to remove that mostly-dry cake from the bowl of the centrifuge and take it outside where it can be put in containers to transport the cake offsite for use as compost or biomass for a second op beyond the initial extraction I’m interested in

Sure, I get that a solid bowl centrifuge is for separating your ethanol & plant chemical solution away from your biomass, that wasn’t what I was asking. I’m wanting to know how to get the spent biomass that’s coming out of the centrifuge away from the centrifuge and to the outside of the building where I can transport it elsewhere.

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Ah ok, sorry I misunderstood. I’ve only used big open top rolling totes

we have some ideas that may reduce the labor involved and be more automated. The product has ethanol or butane in it? what level do you need it down to before disposal?

NSEP makes at least some of their machines with removable rotors. Not certain about the 55series. They also offer a rotor hoist for lifting them out. The engineer I talked to said they build all their machines to order…(long lead times).

I got the impression that it might be possible to incorporate minor mods into the design. especially if they are features already offered on other models. ie if the stock rotor in the 755 doesn’t have mounting points for their rotor lift, adding them would not be problematic. That was not explicitly stated, but was definitely implied.

Ethanol. Don’t need to worry about the level as long as it is relatively dry cake which the centrifuge should accomplish, but I do worry about the vacuum system’s ability to handle any ethanol vapors that may be coming off of the cake.

I think a removable rotor would be better than nothing but ultimately I think I’d still rather have a vacuum system to handle the spent biomass, if you pull the rotor out and have a second to swap in you still have to worry about inverting the rotor to dump the majority of the spent biomass, cleaning up the fines left in/on the rotor and some nonzero amount of ethanol fumes from the rotor/cake combination moving around inside your building

the topic of explosion proof vacuums has come up…

moving biomass by making it into a water slurry was helpful when I first started doing cryo-ethanol in beer kegs (unmodified) . I didn’t bother unpacking the first one till I ran out of kegs. Once I proved they could be emptied with a garden hose I handed the task off to a minion.

Not as relevant to emptying the centrifuge as a 500gal reactor.
there might be more appropriate centrifuges…

Have you considered using filter bags as a removable basket lining similar to the delta separations model? There are a myriad of sizes and densities available online and a few places offer custom fabrication if you can’t find a size that fits your needs. You could stock up and have few minions on either end of the centrifuge process filling and emptying while the spinning commences to keep the process moving fairly smoothly…

That just seems like adding another step to the process compared to an actual vacuum system, as well the NSEP 755 holds about 100 lbs of dry biomass so I think that’s going to be a problem, a mesh bag is going to have a hard time putting up with that kind of weight

It might end up being that it would be a similar time to just swap bags as opposed to vac’ing out but i don’t have any data on that… As far as the abitity to handle the weightt goes, I know there are suppliers that will customize them for you to handle most any capacity you desire. I was previously in talks with the guys at Boldt bags to create extraction bags formed to line IBC totes and lift out with a fork lift similar to the soil totes that you can pick up at the grow shops. I ended up scraping the project but i don’t see why this couldn’t be applicable to your needs.

Happy hunting

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You’d be amazed what people just leave lying around once you own a forklift…

a 200lb mesh back of sopping wet cannabis was not on the list of things I had considered…is now :slight_smile:

how long did you plan on drip drying the bags?

I can see holding them up with a forklift getting old pretty quick.

I didn’t see maximum solvent recovery using gravity till about 3 days, but I was using mostly closed vessels to reduce evaporation


The client didn’t really seem too concerned about reclaiming solvent, they were just using iso and not being the most eco friendly about it… I wasn’t to heartbroken to not go down that road with them. Green buggy, if you have the flexibility just go with the western states top load/bottom empty, it has an internal scraper that assists in automatically emptying your payload. They quoted me around $250k…

Youch. The difference between the cost of a new NSEP 755 and a Western States automatic is literally almost what my house cost.

Seems to me that there’s a lot of woodworking shops that have sawdust-handling air systems that handle explosive dust with cyclonic separators that cost a lot less than $210k. There’s gotta be something out there.

How about having a frame built so you can tip the thing upside down?

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Not a bad idea but it still means a lot of labor intensive nonsense. No serious commercial woodworking shop has grunts moving hoppers full of sawdust around from machines that are being used for continuous production…