Heating wood for association workshop?

[emlaurent]

Hello,

To heat the open Technistub workshop, we are looking for an economical way!
The workshop has an "office" area of ​​60m² which will be separated from the rest of the workshop by an insulated partition. The rest of the workshop, 100m² and with high ceilings, is not insulated.
But, the walls are made of bricks with a thickness of 40 to 50cm, which is not too bad. On the other hand, there are bay windows in single glazing with rotten woodwork ...

So much for the decor!
The "office" area is for electronics, 3D printing, and computers. It must therefore be heated with a "comfort temperature" and therefore have a minimum of regulation.
For the rest of the workshop, it's less critical and you need a little extra when it's really cold.

We started with a solution based on reclaimed wood (disposable pallets, cuttings, etc.). Even if the pallet wood is of poor quality, there is enough room to store it and "regular" supplies nearby.
The idea would be to have a large boiler, like 1m deep, to be able to put pallets cut in 3: not too much painful work to cut and we load the boiler for a good outbreak.
With a buffer tank and 2 radiators in the office part, that should do it.
The losses from the boiler would heat the workshop part

What do you think ?

For the boiler, there are horizontal hearth boilers 80 to 100cm deep by 40cm in diameter which would be fine. We are looking for the right opportunity on the side of Alsace .... (If you have that )

If not, is it doable to build one yourself?
A rustic model even if it is less effective ...
In refractory bricks like the rocket stove?

Thank you for the good ideas!
Emmanuel

[Ahmed]

Boilers of the "can" type correspond well to the use of a coarse fuel, as described; however, the quality of combustion is the weak point of this material.
It would be better to condition the fuel less summarily and have a correct stove, small enough for it to heat up ...

For the workshop, given the criteria: not insulated, high ceiling and auxiliary heating, it would be better to see on the side of infrared radiant gas.

[AXEAU]

Hi,

I had a 150 m² workshop with a high ceiling that was impossible to heat. I stretched wire spaced 50 cm apart at a height of 3 m and stretched plastic sheeting over it.
It's easy to do, economical and efficient. Whatever your means of heating there is a huge difference.

jlg

[emlaurent]

Boilers of the "can" type correspond well to the use of a coarse fuel, as described; however, the quality of combustion is the weak point of this material.
It would be better to condition the fuel less summarily and have a correct stove, small enough for it to heat up ...

well seen the thing of the volume of the hearth which is likely not to go up in temperature
On the other hand, repackaging the pallet so that it goes into a "normal" boiler, it will be painful with nails and poor quality wood ...

Isn't it better to consider that we will consume more wood because of bad combustion but since the wood is not bought, it is less critical ...

For the workshop, given the criteria: not insulated, high ceiling and auxiliary heating, it would be better to see on the side of infrared radiant gas.

there is no town gas supply!
And then, it may be expensive for an association workshop ...

I had a 150 m² workshop with a high ceiling that was impossible to heat. I stretched wire spaced 50 cm apart at a height of 3 m and stretched plastic sheeting over it.
It's easy to do, economical and efficient. Whatever your means of heating there is a huge difference.

yes, it's an idea! The height under the ceiling is sometimes very useful!

Emmanuel

[Rabbit]

I have search on google if there were pallet stoves but n in
have not found. I think the best solution is to design one
and do it with steel plates.
This should be able to be done at a reasonable price by cutting
the sheets when buying and have them welded by a pro (those who
weld steel tanks). In this way you could introduce
the whole palette.
You should use an open expansion vessel to avoid bad
surprises. In addition it limits costs and is a real security. he
should also provide a large buffer tank (1 or 2 m³) for
ability to absorb combustion spikes. A euro pallet weighs
+ - 30 kg at 4 KW / Kg, even if we divide by 2 to take into account
the performance and the humidity of the wood starts to count.
ref: http://forums.futura-sciences.com/habit ... diere.html
ref: http://fr.wikipedia.org/wiki/Bois_%C3%A9nergie
To get an idea:
http://www.maison-facile.com/060-temps-chauffer-eau.asp ( introduce
1000 l, flow 6 ° c, T expected 99 ° c, Heater 60000 w)
As the pallets are often made of softwood, slow combustion is not necessary and a chimney duct made of rigid stainless steel tubes. Also provide a
automatic water supply in case of overheating.
The nails can be recovered to be sold for scrap.

The buffer tank could act as an open expansion vessel.

[chatelot16]

I heated myself for a long time with old pallets in an open fire: it allowed me to put almost whole pallets without much work ... but it took a lot: it is not the right solution

now I mostly burn woodchips: I know a sawmill that sells them cheap

my goal is to make a boiler accepting wafers much coarser than that which is sold, to mix there other wood crushed by my own means

for example crushed garden waste is very difficult to dry, it rots and loses all its energy: mixed with dry wood already dry it dries very well, because the humidity is immediately lower than it must rot

my preferred heating solution is gasifier, but this gas which is mainly deadly toxic carbon monoxide is a little worrying in a closed building ... we can therefore prefer a simple hearth

all means are good for putting a wood-burning stove in a large oil boiler

[Philippe Schutt]

It seems to me that by taking inspiration from a rocket stove with vertical loading it should burn the pallets fairly correctly, and without having to break them small.
http://bushcraft.fr/phpBB/upload/images/sumadinac_rocket-stove-small.jpg
This kind, but also by covering around the wood to be able to make very ventilated loads.

[emlaurent]

It seems to me that by taking inspiration from a rocket stove with vertical loading it should burn the pallets fairly correctly, and without having to break them small.

This kind, but also by covering around the wood to be able to make very ventilated loads.

Indeed, I started to think about such a design.
With a large loading area to be able to thread an entire pallet or a pallet cut in 2 or 3.
If I understood correctly the functioning of a rocket stove, the draft is sufficient so that wood loaded vertically only burns at its base and not completely.
In most stoves, the loading area is square and the afterburner is circular or square. To put pallets, it would surely be necessary to have a rectangular post-combustion zone (see diagram below) to limit the space that the boiler takes and also so that the rise in temperature can be done in relation to the volume ...

What do the rocket stove specialists who pass by here think?

Something like that :

[chatelot16]

this top feed works well only at high power

there is a risk that the pallets take up too much space for not enough wood and do not make a fire sufficient for the size of the hearth

I am testing fireplaces with brick or refractory concrete plates in which I can add wood in small pieces and other combustible waste

continuous automatic wafer feeding guarantees a very high temperature

[Ahmed]

I agree with Chatelot16; I add, and this only reinforces his remark, that the air intake must remain of a sufficiently small dimension so that the speed of the incoming air keeps a sufficient speed to ensure correct operation (this speed is limited by the natural draft of the exhaust pipe).
Otherwise, smoke backflow and hazardous combustion are more than feared.
Entropy and experience show that there is a greater chance that any device fairs rather than working spontaneously!