Auger prototype for corn/ pellet / wood chip burner

[Old F]

Auger prototype  for corn/ pellet / wood chip burner

Doing some tinkering .

After seeing what it was costing  my sister to heat a building for her small animal business.

I  am setting out to see what I can do to help her out .  She supplies pet stores with all kinds of  small furry critters and lots of them.

 On A weekly basis she use about 3 to 4 bales of pine chip bedding when cage cleaning.

Right now all of the bedding coming out of the cages is being spread out on  fields .

About 80% of it is dry enough to burn on a grate and has waste feed mix in with it.

It won't  be to hard to keep the dry  separate  from the really  wet.  Should be enough to  supply  heat for the barn for two or three day a week.

I am looking in to two ways of burning it .

 One is to use a well insulated fire box load it and go for a fast hot clean burn and the hot gases would go thru a heat exchanger and store the heat in water or for  hot air a rock storage bin like is use with hot air solar.  For later use.

Two is setting it up like a home furnace firing on demand.  A little trickier  but still  doable I think.

Ether way  I  needed an arguer to get the pine chips in to the fire box or pot .

I spent hours searching the web and could not find anything close to what I needed   or could afford    .

Probably one reason  why you don't here of many home brew corn or wood pellet stoves.

I wanted to stay away from  cutting piecing and welding  can be done but it's a real pain .

   And make it more of a kitchen table  project.

Here is what I have come up with so far.

That's right wood and rope and no it won't burn up as it will never see the fire directly .  

The rope is 3 8 inch and the dowel is 3 /4 inch this fits nicely in an 1  1 2 pipe

  I held one end of the rope with a hose clamp an ran a bead of glue the length of the dowel .

Then coiled the rope on it and use another clamp to hold the other end  till the glue dried  

Another one I am thinking about is a spring type auger using 1/ 8 inch round steel stock.

Just  wind it on a length of  1 1/ 4 pipe  then stretch it  out .  

Here is the hopper  the full size version will hold 9 to 10 cubic feet of bedding

The test  fire pot is a can that had pop corn in it. The ones that folks give out on the holidays the new fruit cake  : )

Its lined with 1 inch thick   ceramic fiber insulation rated for 3000  F .   Neat stuff  easy  to cut and work with.

After  some hard firing I haven't  scorch  the paint on the can.

The chips are augured  in to the air blast and the air blast blows them in to the fire box.

I am turning the auger by hand now and have ordered two 12 volt DC  motor  controllers .

One for the auger motor and one for the blower.  Besides good air and fuel control I want to have battery back up.

At this point I am guessing that the wood chip bedding will provide about 5000 BTU per pound.

By angering and burning  1. 6 oz  a minute  I should have a burner rated at about 30'000 BTU an hour.  

More fun things to do  finalize burner design and  work out grates and fire pots for corn and wood pellets

This where I am at right now .    A lot testing an tinkering  needs to be done.      I will try to keep post up dated with any thing new.

Still having fun

Old F

[pyrocasto]

I'd be interested in how it preforms. I would think with sawdust that you'd either blow it out of the bucket, or it would build up on the bottom. I have access to enough sawdust so I was curious how well it would actually burn.

[electrondady1]

old f , that auger looks great. that's been the part thats been stumping me for a long time. i'm thinking if you used a steel cable instead of rope it would be ok if it did get a bit hot.

[Old F]

Well Chris

The can is a test bed for grates and air flow and not a finale burner in its self.

The blower I am using now  is way to big  and I have to watch how fast I set or it will blow chips out.

It s going to be a delicate balancing act between air flow and fuel flow for controlled BTU out puts.

I dumped a 16 oz charge in the can with a stain steel screen as a spark arrester and  lit it off with the blower at 1/ 4 out put  in less than a minute there was nothing left of the chips but a small amount of fine ash and there wasn't any thing left of the of the screen melted it right down.   Roared nicely to  :   )

I have ordered a smaller 12 volt blower and a DC motor controller kit it should be in some time next week.

This should give me finer air flow control.

Old F      

[Old F]

elctrondady

I thought of that to  this was just  a quick an dirty prototype .

 What have you been planning?

Old F

[nanotech]

I work at a little known place called Woodmaster ( http://www.wodmaster.com ) and one of the newer models they have is a corn burner.

The reason it's been so long in getting to market is the fact that the corn burning in the firebox would quite literally melt most metals that the conveyer or auger were made of.  Finally it came down to just plain old pot metal.

Yes, corn burning in a stove gets THAT HOT!!!  The two corn burning furnaces that we have at work that heat the entire 75' X 300' sheet metal building (in-floor radiant hot water heating) are backed up by one of the 6500 model wood burners.  Inside the fire box there is a 4" X 8" X 2" pile of corn kernels that are glowing almost white hot during normal operation.  That little pile of corn heats and maintains 110 gallons of water at 155 degree F.  And when you open the firebox door, letting in a rush of VERY cold fresh air, the WHOOSH of the fire is intense!!!

For any moving parts in the actual burner, you're going to need some pretty hefty stuff.  Whatever your conception of the temps is, TRIPLE IT!!  In the AFS1100 corn stove we make, 1/4 inch stainless rods melt in about 5 minutes flat.  1/4 inch cold rolled carbon steel doesn't last much longer.  The auger shafts we use are 3/4 inch, with the auger blade (the rope bit on yours) being 1/2 inch thick and making the auger diameter a total of 2.5 inches.  And they end up glowing a yellow color.  Not red, YELLOW!!  And they are HEFTY!!  They're about 2 feet long and I haven't actually picked one up myself, but I've seen the guys that do.  They ain't light, mister!!

Pellet burner stoves need some SERIOUS engineering put into them.  I was thinking of making a small one for my house, as I've only got 520 sq ft and the AFS1100 nominally is designed for 2,500 sq ft and more.  Anything less and the fire will actually go out inside waiting on the water getting cool enough to energise the blowers......

Needless to say, I've given up on that idea.  Way too complicated for me (and I have no problem rebuilding a car from the ground up.  Mechanical, electrical, plumbing, fuel.  You name it, I can do it, but those corn stoves are too much for me).

[nanotech]

DOH!!!

Missed an "O" in that link...

It should read http://www.woodmaster.com

[Old F]

Nanotech

I think you meant cast iron not pot metal. One of my hobbies is metal casting

In some hobby casting circles it not a burner innless you can here it a block way and it can melt cast iron .

Sounds like Wood Master is using a bottom fed burner to manage clinker formation.

For this size and type of burner  every thing would have to be built like a tank to handle the heat .

There are other types of burners were the auger won't see direct heat from the fire.

Small burner are even trickier  but if was easy it wouldn't be any fun  ;  )

Oh and if you check out my web sit you find I am a  Wood Master customer  :  )

Old F  

[nanotech]

Ah, yes.  A 434.  A little before my time, but I still hear about them from some of the people that have been there for a while.

It very well could be cast iron.  I haven't taken THAT close of a look.  Been more interested in getting my job (insulating, wiring, and plumbing the wood burners) down pat and learning the ins and outs of it.

I do know that the corn burners have 5 augers in them : (from top to bottom)

The feed auger that brings the corn from the hopper

The feed auger that actually feeds it into the burn box

Two (I call them) scrubber augers that help keep the corn from just piling up in one spot (these are the ones that get glowing yellow hot).

Then the ash auger that pulls all the burnt stuff out to the ashpot in the back.

It's quite the complicated chain drive system they've got at the back to drive them all.  Everything (including the blower fan) is temperature controlled.

Something to note : I guess your 434 stove doesn't have an ETC?  The models I work on have an electronic control panel on them that allows you to set what temperature you want your water to be at.  This panel then thermostatically controls the blower fan to control the fire in the burnbox so that the water stays at a constant temperature.

[Old F]

Nanotech

My  434  doesn't have ECT.

Were I work they are phasing out some Alan  Bradley   temperature controllers.

If I can get my hands on one I plan to up grade it .

Old F

[zap]

I've seen where some use a shop vac to both move and clean their corn before burning. I know you're not using corn but could you maybe replace your auger with just your blower? Some percentage of the total air from your blower that could be diverted and used to blow the used bedding into the burn pot. It might just blow the whole charge completely out of the burner but you might be able to set up a cyclone effect that would keep the fuel in a low pressure center. Sounds like fun project just the same.

[Phil Timmons]

Just my 1/2 centavos --

I really like the idea of vacuum/blowing the material for the general handling.

Sister could even use a hose to directly sweep through the pens and take an entire step out of handlling the material.  I use a 40 foot long (or so) 2 inch swimming pool hose on the end of my shop bulit shop vacuum (ran by a 220 commerical auto cleaning vacuum).

Anyway, it reaches all over my warehouse without moving the vacuum motot/tank.  I stick a 10 foot piece of 1-1/2 inch PVC conduit on the end and reach everywhere.  If they did something like that could go to a gravity (elevated) trash tank that just did a gravity drop to the firebox.

A gravity hopper could do, or use a push piston in a pipe to feed metered amounts of fuel.  

I would caution against directly blowing dusty material directly into a firebox.  Potentially explosive.  

But jumping back to the start -- very creative on the rope auger.  Might steal that idea for something, someday.     Thanks.  

[ruddycrazy]

Just an idea for you Fred,

                          I'm thinking of making up my own burner but rather than use sawdust I'm thinking of compressing the sawdust into bricks that way an auger won't be needed. By lining an entry with refactory a simple shute can be made to feed the furnace. My mate over west has done a similar thing to get rid of his saw dust waste and heat his shed in the same process and his setup is a beauty.

Cheers Bryan

[Chagrin]

If you're looking for a metal auger you might try an auger drill bit. You can get some cheap imported ones for a few bucks at places like Harbor Freight, etc.

[Old F]

Were to start

Zap  it can be done I have heard of some one  megawatt stand by power plants that are fired this way.

But its hard to scale it down to size I need and the control  I am looking for.

Phil

The problem with a Vac.system is that we are talking about small animals mice rat hamsters and alike.

They like to hide in the bedding an could have a rude awakening and fine them selves  in the trash hopper.

I have come up with some thing better than rope round stove gasket you can find it in lots of different diameters.

Than use back iron pipe for the shaft it should hold up to a lot of heat. So steal away  : )

Chagrin

What I need will be 3 or 4 foot long and 1 1/ 2 inc to 3 in diameter

Thro they mite work for corn and wood pellets

Old F