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 
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
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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…
You’d be suprised at some if the production I’ve worked where bins were the norm. Machining especially, cnc machines may have an auger but a man still has to move and dump the bins. Your turn over fixture needs to be hydraulic with a simple lever allowing the operator to dump the centifuge basket onto a bin on a forklift.
@Mr.Amagi What is the capacity on that $250k machine?
I absolutely agree that if you’re not doing the extraction in the centrifuge (to control solvent residence time to the second) then a “flow through” design like Western States offers are the right way to scale.
Where you looking at the Quadramatic or the QuadraClean?
tilt to empty is implemented on 100gal steam kettles, so it’s not a terrible idea.
the required shake suggests looking at the hydraulic lifts used by the garbage collection industry might not be a bad idea.
looking harder at NSEP’s removable rotor implementation might reduce the hardware requirements for a fairly similar gain in efficiency.
if you’re into freezing your biomass, freezing it in the basket could be spun as a feature to justify the cost of multiple baskets…
I think there’s some very big differences between what I’ve seen of commercial metal shops and commercial woodworking shops as far as waste material removal/recycling.
For one, if we’re talking about metal lathe chips, unless you’re pushing the machine within the right parameters to chip break properly, you get long stringy chips, and you might get them anyways depending on how gummy the material is (stainless is especially known for this behavior). This shape doesn’t lend itself to vacuuming up well, in any material I’m aware of (have definitely experienced this when machining certain plastics like UHMW and urethane)
Also, from looking at the mess in my metal shop where I’ve got a 17" lathe, CNC knee mill and a VMC, depending on what and how you are cutting the chips end up all over. Coolant may wash small chips downwards where an auger may pick them up but when we’re talking about vacuum systems, its hard to plan for chips that go everywhere instead of landing in a predictable place - doubly so when we’re talking about trochoidal toolpaths that shower chips in all directions.
The fact that machine shops don’t and frequently can’t use a central collection system doesn’t really change my contention, that we could and IMHO, should be using a central collection system. Woodworking shops have been using them for collecting a waste product very similar to my hammer milled biomass for 50+ years for a reason.
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You’ve got a point in the chips being different, I programmed lots of machines where the chips simply fell onto the floor to be swept up. One concern for dust collection is good grounding on your metal ductwork. That and an explosion proof motor and it should work.you may want a good fire suppression system as well, when things go wrong you have a lot of air to assist a fire. Cabinet shops are victims of fire like any other industry. What industry’s does your shop cater to? I’ve got a haas sl20 and a haas vf oe. They fuel my insanity…
The biggest difference between your hammer milled biomass and the woodworking waste that you’re comparing it to would seem to be the residual solvent and it’s flamability. Sure, wood dust is problematic, but Ethanol vapour above its flash point seems like a much bigger problem. The solvent also adds weight and a degree of cohesion to the material that is absent in wood working waste.
I’m using material post CUP as my metric here, and the NSEP spins quite a bit harder.
any chance you could share your milling solution over here?
Edit: they’re a little out of the way, but mbar might be able to address the feasibility & build out cost associated with a vacuum based spent biomass handling system. I’ve known the owner for almost 50 years, and will pose the problem to them via email…even though none of us are likely to import a system from New Zealand.
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