Making a biomass boiler ... flameless

[Ahmed]

Yes, cortejuan, the experiments I attended were aimed at producing hot water from cold water and not inside a circuit, which is actually quite different and you are right to emphasize this.

Regarding insulation, Marc91, it is not necessary to cover with 10 cm of soil: a thin layer of ground material plays this role perfectly by not participating in the fermentation.
Everything plays at this level, between the surface of the heap and its volume: we see that for a significant volume the loss remains minimal.
I fear very much that by disrupting this relationship with the addition of new areas of exchange, we will come up against unfortunate disappointments ...

[Grelinette]

Similarly, and regarding the type of decomposing waste that produces heat, equine owners have all observed that bundles of wet fodder (straw, hay, alfalfa) can reach very high temperatures, much more than 60 °.

It is even said that a flood, or simply the rain, which moistens the fodder boots of the first level of a stock (those on the ground) can cause a fire!

Currently most wheat producers prefer to grind the stalks (straw) after harvesting wheat or barley rather than picking it up. A way of using this straw could be created.

I do not know if this has already been measured, but I would be very interested to know the calorific value of a simple bale of wet straw (maximum temperature, reaction time, etc.).

[Gaston]

The average installed power over 225 days is therefore 307 Watts, or 12,3 W / tonne, with 25 W / t in peak power (fermentation peaks).

So in the example subject of this post, with 3 tonnes, we could get around 40W with peaks at 75W (assuming that the proportion of heat losses is not increased by the small size of the heap).
It is very clearly insufficient for a heating circuit, it may just be enough for a small daily shower (about 10 liters per day at 45 °)

[marc91]

It is very clearly insufficient for a heating circuit, it may just be enough for a small daily shower (about 10 liters per day at 45 °)

for the strong ones in English (which is not my case), I found this site

http://www.permacultureactivist.net/Pet ... _Pain.html

and this video which presents a realization like jean pain

http://www.youtube.com/watch?v=qSIMqWCTS1Q


I also had a Belgian who claimed to have built a heating system with a heap of 15 m3, I am actively looking for it.

[Gaston]

for the strong ones in English (which is not my case), I found this site

http://www.permacultureactivist.net/Pet ... _Pain.html

The quantities presented on this site are of another order: we are talking about a pile of 50 tonnes to heat and supply hot water to a house for 6 months ...

I fear that this system is not easy to reproduce on a small scale.

[marc91]

[quote =: we are talking about a pile of 50 tonnes to heat and supply hot water to a house for 6 months ...

I fear that this system is not easy to reproduce on a small scale. [/ Quote]

indeed, rereading the writings of jean pain, the heap of humus harvested at the end was ... 25 tonnes

on the other hand for those who have a large amount of fermentable materials, heating a greenhouse with should not be a problem, thank you all for your answers.

I put in attachment a table of the temperatures obtained during the decomposition

https://www.econologie.info/share/partag ... 7M8yAx.jpg