Woodmizer Sawdust Burner . . . . .

[Rockn H]

Will the smaller units be the same as your normal pellet stoves?  Just burn loose sawdust instead of compressed?  Has anyone heard any prices mentioned?

Hasn't someone on here showed plans for a sawdust burner before using forced air to stir up the dust and cause it to burn hot?

[BBTom]

I am getting ready to build one that fits inside my taylor, just need to find a good variable speed feed so I can experiment with different feed rates, anyone have a burned out pellet stove they want to get rid of??

[Ernie]

I visited a sawmill this summer that had their own sawdust burning boiler/generator. 160KW generator that burned only sawdust,

Did you notice if they had to dry the sawdust first or could they use it straight from the mill?

[Riles]

The sawdust, splinters, chips, stray bark, etc all moved by conveyor systems. Normally it fell into trailers and was sold to the OSB mill or the particleboard plant. Instead they sorted the bigger stuff out and dumped it into a pile in an open sided building and augured it into the boiler room. From the augur it fell onto a shaker conveyor which sorted out the sawdust that went into the boiler. The larger stuff went back around. I was told they could grind it, but had the impression they didn't do it because they didn't need to.

So to answer your question, no, they do not specifically dry it, although it's handled quite a bit and that may have some affect. The boiler did have forced air into the firebox but I don't think it was a "fluidized bed."

[ElectricAl]

Here is a little more information.

Bio-Mizer Biodust Burner



Pictured is the Domestic 150,000 btu/hr

*Can burn any suspended bio-dust
*Computer controlled with push button simplicity
*Fuel bin holds up to 3 day fuel supply
*Integrated fuel delivery system
*No clinkers (WM sawdust )
*Super clean emissions
*Hydronic heat system
*Air-to-air heat system
*Minimal ash buildup ( WM sawdust )
*Auto ash removal
*Environmentally friendly
*Doesn't "turn down" and smoke like stick burners do.
  This machine turns off when not needed, and reignites in seconds
  with the back up fuel system. Hot ignition virtually eliminates smoke on startup.




It is possible that the design of the Bio-Mizer may change some before it is for sale to the public.  But this gives every one a product update.

[farmerdoug]

Al,  I see you received the mailing from Woodmizer too.

Farmerdoug

[Riles]

Any ballpark costs?

Found a related link:

http://www.stirlingengines.org.uk/manufact/manf/usa/new6.html

[Paul_H]

Link

I had remembered this old post by Bibbyman and I made a lot of inquiries including Woodmiser,who informed me it was Don Laskowski's pet project.I e-mailed him and asked if there was any more development and I received from him(Don Laskowski) a very curt reply that he had no more involvement with the project.

It left me disatisfied with the lack of answers and I still would like to know what problems the Stirling had,was it a lame Duck or were there politics that ended the project. :-\

[ElectricAl]

Doug,

We got it on Monday ;)



Riles and Paul,

Sunpower and Woodmizer have split up to put it nicely

WM is working on a new system for the Bio-Mizer co gen. I have been told it's better technology than the Stirling engine

[Bibbyman]

The Bio-Mizer web site is up.  Don't tell much we don't already know but if you're interested in keeping track of the developments, it'd be a site to mark in your favorites.

Bio-Mizer

Anybody hear any price/availability details?

[wwsjr]

I thought I had a card from the guy who was at Perkinston with the Bio-Mizer, can't seem to find it.  I think he told me it would be in the $6,000 range, not sure but my feeble memory came up with that number from somewhere.  He did not give me a date of availability.

[Bioman]

Hello to all,

Bioman is the new representative for Wood-Mizer.  We thought we'd jump in here to help answer questions related to the sawdust burner we are working on.   We're not here to sell (can't because it isn't ready yet). 

Since this is a forum, we thought this would be a great chance to hear from others on the realities and potential of the ways we can utilize biomass in a dust form.  We believe BioDust has the potential to become that 'new fuel' we've been looking for to make a dent in our dependency on oil on a global level. (There's nothing wrong with thinking 'big' is there?)    I think you'll see what we mean as this thread progresses.....

[Bibbyman]

Welcome to the Forum Bioman!

I think you're going to get a lot of questions and suggestions.

[twobears]

WELCOME BIOMAN:i,am very intrested in all this as i,am sure many others are.

   delbert

[Bioman]

To those who have researched sawdust burners I'd like to summarize what we've found and then respond to rebuttals.  Maybe we've missed something in our studies of the technology.

When you find a machine that burns sawdust it is typically large and expensive.  It also requires the dust to be relatively dry.  Sawdust will not be the best fuel for the unit - the unit is typically optimized for chips or some larger configuration.

Burn back, clinkers and host of other issues plague current technology when it comes to burning dust.

Most small scale versions simply don't work well or not at all.  If they can burn dust, it is not the optimal fuel. 

You can find drum or bucket smoker style burners but they are not going to solve the heating needs of a typical home today.  They smoke a lot.

There has been a lot of research done on developing small scale dust burners in all corners of the world - to date, we haven't seen or heard of a viable small scale unit that works well and/or falls in a decent price range.

If you do find a sawdust burner, almost without exception the sawdust has to be dry.  Wet sawdust is by nature hard to burn and smokes a lot.

All things considered ,if there was an answer to the list above, wouldn't the product already be on the market and obvious to us all?

[beenthere]

Sounds good to me, Bioman. Now when talking of sawdust to burn, and BioDust, how similar are they, and what would be good definitions to separate them? 

BioDust
Moisture content? 
particle size?
Screening necessary?
hammermilling necessary?
drying necessary? 

[Bioman]

Bio-Dust is simply any form of biomass in a suspendable dust form. 

For sake of grounding future discussions on Bio-Dust burning it is important to agree on one factor; generically speaking biomass has a heat value of approx 8500 BTU's per pound (dry).  That means it doesn't matter if it is wood, corn, grain etc, they all have roughly the same heat value per pound of dry weight.  The primary difference between fuels is moisture content, ash content, density and how it can be handled.

The reason we are chasing the Bio-Dust form of fuel is because most forms of biomass can be turned into a 'dust' configuration with relative ease (someone already mentioned hammermills).  Also, we have a huge customer base wondering how to either get rid of the dust created by their wood processing equipment, or even better - use it for profit somehow.

Now that we know how to handle and burn Bio-Dust effectively and with relative ease (even wet), it's simply a question of which fuels are most readily available.  Certainly the sawdust created by bandmills (and circle mills) is significant in the beginning.

Here's a thought starter for you.  Why do we burn the corn kernel that has most of the cost associated with growing it and has multiple other uses when we can burn the cob in dust form instead and get the same BTU/lb?   Today the answer is 'because there isn't a good way to burn cobs.'  What if farmers had an opportunity to grind cobs and sell dust (that is already dry) at a price that would rival corn?  My guess is there is an industry waiting to be born with this one crop alone....

[Furby]

What currently happens to the corn cob?

[Bioman]

Field corn cob is thrown back onto the ground to rot.  Popcorn manufacturers have mountains of it with little market to move them.

[Furby]

Not in the fields I've been in.

[Bioman]

Sorry beenthere, I see I didn't fully answer your questions.

The industrial burner burns dust directly from our sawmill operation - moisture is typically around 60%.  Tghe domestic unit works best with dry fuel (30% or less).  It can burn wet but it isn't very efficient.  In any case - energy is required to drive off the moisture before the wood fiber can burn - so the dryer the better.

We don't screen our fuel on the industrial unit but probably should - the auger we use can hang up on large pieces of bark or metal parts that find their way into the conveyor system.

When we screen for the smaller unit we're using a mesh with approx 5/16 holes in it.  The auger is much smaller on the domestic unit so some care must be taken.

Hammermilling of other fuels like corncob will be necessary - bedding purchased at the farm store is too course.  This is one area we will be working on - we'll need a reasonably priced hammermill for this market

Moisture

[Bioman]

Furby, what type of corn were they growing?

[Furby]

Field corn.
I assume the cobs were being ground and spit out with the corn, as they sure aren't left in the fields around here.
A few here and there are always laying around, but not that many.

[beenthere]

I think you are right Furby, that the cobs are ground somewhat in the process of removing the corn kernels. But the cobs in various forms are left in the fields - using the modern day combines. 

Years ago, we picked whole ears, stored them in cribs, and then would have a sheller come in and shell the corn, leaving corn kernels and big piles of cobs. These cobs made good fuel for heaters. Burned a many of them to heat water before taking a bath. But the density isn't so great, like wood. So a pound of cobs would be more volume compared to a pound of sawdust.

Green sawdust would give fewer BTU's I suspect, just as green firewood gives fewer BTU's. Seems if a sawdust burner would burn green sawdust, then a sawdust drying step could be saved - as the green sawdust would 'dry' so-to-speak, as it is being burned. Hopefully a net gain in energy would result.

[Furby]

What I've seen is simply fields with nothing but stuble.
The corn, cobs, and stalks are all gone.
Being ground and left in the field is possible, but I didn't see much if any grindings.
There is a large amount of "dust" blowing away as the corn is thrown into a trailer though.
I do remember reading how some farmers were using it all in the feed.
I guess I'm wondering if there would be a lot of extra work seperating and collecting the cob and stalk remains in order to burn them and wether it would be a negative from the feed side of things if that's what is curently being done.