CEB Masonry Stove

=Introduction=

We are interested in a masonry stove made from CEB blocks. This is highly experimental - thus it must be kept simple. Nonetheless, we are aiming to have a hybrid wood/Babington flame. The combustion chamber should be designed like a wood stove - with a grate and ash compartment. We are making a mobile Babington burner in a tube or square - such that we can simply insert this into the combustion chamber. To do this, we need a small inlet hole in the door or from the top - for air delivery. We need a small hole from the top for oil delivery. The oil sump can be placed in the ash compartment, or via a tube to the outside. The oil must dribble on the Babington ball from the top. We are considering putting a metal plate on top - for cooking as well.

=Possible Implementations=

There are many details to the above scenario. Here are some variations:


 * Basic design - wood oven only, testing the durability of CEB block in high heat conditions.
 * What is the simplest implementation of this?
 * Could this be as simple as a big CEB box, with metal surface on top?
 * If we want the hot air to circulate up and down in the structure, what is the simplest way to do this?
 * Basic design with insertable Babington - not much more complex than the first, with the only requirement of air and oil inlet, and provision for collecting of excess oil
 * Addition of cooking surface - this makes it more complicated

One way to do a flexible stove is to start by building the chimney - and then stacking movable bricks into a configuration that succeeds in building a successful burning chamber. Then we add a metal door, ash compartment door. We could have a bunch of bricks on hand - and when a successful configuration is achieved, we seal the outer bricks for smoke?

=Simple Implementation= Important: the flue from the burning chamber trough the chimney. Therefore all the joints (walls <-> cover <-> way out) should be mor ore less air-tight. Thats easily done with clay.
 * Fundament made of one or better two layers of CEBs or concrete
 * Walls with CEBs
 * Metal plate as cover (for cooking also)
 * Way out to the chimney, preferably in the upper part of the back wall
 * Plate slide or something similar to close this way out. As soon as the wood has gased out, close the way out to keep the stored heat.
 * Removable metal plate as front door

=Background=
 * For what kind of object will the masonry stove be used, hexayurt, cordwood, CEB house? Wall, thickness, insulation?
 * CEB room
 * The dimensions of the room? The rule of thumb here is that 1 kachel (dimensions about 0.2 * 0.22 m) heats 1 m3 of space
 * 60 by 20 by 10 foot space
 * How much time is there for the design and build process?
 * We only have 6 weeks as of 9.5.08 to build the shell - but we can work inside on the stove after that
 * What are the preferred materials, clay, CEB, concrete ?
 * CEB is preferred

=Pictures= http://s307.photobucket.com/albums/nn307/sashamr/masonry%20stove/ =Examples=

Available Plans
See here: http://www.einfaelle-statt-abfaelle.de/index.php?#Ofenbau for:
 * Steinöfen setzen
 * Steinöfen-Baupläne
 * Abwärme-Öfen aus Ziegelsteinen und Lehm
 * Öfen ganz aus Lehm gebaut

Outside bread backing oven

 * Bread baking oven
 * Simple wood fired oven
 * Simple clay oven
 * DIYS clay oven

Cooking stove

 * How to build a cooking stove (video, second half)
 * Rocket stove

=Design Discussion=

Sasha
I would suggest most simple design and most appropriate because of the urgency. Winter is coming and I would hesitate to experiment too much.

There are two ways. Right now, in this situation, If I was on your place I would make stove like this one: http://www.envisioneer.net/stove1.htm#

As I see it you cant make any mistake with this. The only possible problem could be that you should be very careful until its still wet and not cured totally - water + porous concrete = possible explosion I don't think very dangerous, but I am not sure, never tested this. What I like here is the fantastic level of simplicity. What I dont like is the fact that concrete if we trust the books is not very good for this because it will suffer from the heat stress. The person who made it said he is extremely satisfied and didn't have any visible problems. To his design I would only add firebricks in the fireplace because thats where the high heat is, perhaps, the second smoke chamber could be reinforced with roof tiles or even with clay only. That should make things more durable. I wouldn't put any babington burner in the fireplace, that sounds very un-logical to me. If you need that option, and I suggest lets make first a good wood burning masonry stove, you could put the babington outside of the fire chamber. Just the flame should go inside and you have to have a firebrick in the fire-chamber which will dissipate the flame. Also I think a babington is not very silent? I would prefer a babington for a central heating unit. Anyway you can test this option later. Second option a simple masonry stove made of bricks. For the building technique see http://www.dataphone.se/~ncteknik/We_are_setting_up_a_Swedish_ceramic_stove.html You can see how is he assembling the bricks on the back of the stove. You should use same or similar technique. I would think that ceb could act same as those ordinary clay bricks. Is CEB made of clay - whats the material you made it from? Clay is a fantastic material for masonry stoves. You almost don't need anything else. I used it on my stove (some tiles were missing and I used just pieces of roof tiles with a lot of clay and when it hardened I had never any problem with it, In fact it seems like the strongest part of the ceramic stove.

The first stove I suggest should have chanels inside like it is showed here: http://www.dnr.mo.gov/pubs/pub781.pdf something like on page 16. You will need to do some cutting of the bricks and find some firebricks and or clay tiles. I'll send you a explanation in a form of a picture so you understand wat i am talking about. Also for both stoves you need two doors one for the firechamber - where you throw in wood another small one benetah the first one this is for the ash tray.

What do you all say?

Sasha - Show quoted text -

Reto
On Thu, Oct 2, 2008 at 6:04 PM, Marcin Jakubowski  wrote: > Reto and Sasha - let's do a development page for the stove on our wiki - > > http://openfarmtech.org/index.php?title=CEB_Masonry_Stove > > Reto, your work is exquisite - looks like we don't have nearly as much > time as you took to do this - we're talking of a quick implementation > before we freeze here. > > Please read what I have there already, and let's come up with a simple > design. We are talking of starting to build this within a few days. > Pictures will come as soon as we have something. This could be > exciting to see this unfold in reality - based on your help. > Hopefully, we can have an interchangeable Babington burner element in > adddition to wood fire. It seems that this would not be too difficult. > > Marcin > -- > > A human being should be able to change a diaper, plan an invasion, > butcher a hog, conn a ship, design a building, write a sonnet, balance > accounts, build a wall, set a bone, comfort the dying, take orders, > give orders, cooperate, act alone, solve equations, analyze a new > problem, pitch manure, program a computer, cook a tasty meal, fight > efficiently, die gallantly. Specialization is for insects. > > -- Robert A. Heinlein > Reply Forward Reto Stauss to me, mrkflux show details Oct 3 (2 days ago) Reply > Reto, your work is exquisite - looks like we don't have nearly as much > time as you took to do this - we're talking of a quick implementation > before we freeze here.

Understood :-).

> Please read what I have there already, and let's come up with a simple > design. We are talking of starting to build this within a few days. > Pictures will come as soon as we have something. This could be > exciting to see this unfold in reality - based on your help. > Hopefully, we can have an interchangeable Babington burner element in > adddition to wood fire. It seems that this would not be too difficult.

I added some links to examples of clay stoves ... unfortunately again only in German. But there are also pictures.

Reply Reply to all Forward Reto Stauss to sasha, me show details Oct 3 (2 days ago) Reply I absolutely agree with Sasha about not to use concrete but clay.

> I wouldn't put any babington burner in the fireplace, that sounds very > un-logical to me.

I also do not see any sense in this ...

> Second option a simple masonry stove made of bricks. For the building > technique see http://www.dataphone.se/~ncteknik/We_are_setting_up_a_Swedish_ceramic_stove.html > You can see how is he assembling the bricks on the back of the stove. > You should use same or similar technique. I would think that ceb could > act same as those ordinary clay bricks. Is CEB made of clay - whats > the material you made it from?

Question is: are CEBs robust enough for the heat of a wood fire? More durable - at least for all surfaces directly in contact with fire - are firebricks (chamotte).

> The first stove I suggest should have chanels inside like it is showed > here: http://www.dnr.mo.gov/pubs/pub781.pdf > something like on page 16. You will need to do some cutting of the > bricks and find some firebricks and or clay tiles.

With chanels you can maximize the efficiency of the oven because you keep the hot flue gas longer inside the oven where it can warm the storing mass. But it is importent to keep the chimney lenght / chanel lenght ratio bigger than 1.5 (not sure anymore) to have a reasonable flue.

> Also for both stoves you need two doors one for the firechamber - > where you throw in wood another small one benetah the first one this > is for the ash tray.

IMHO you do not need an ash tray. Of course it is comfortable but you can also scratch the ash directly out of the firechamber.

I hope you can translate this kind of english in something that makes sense ...

Reto