Does Damp Coal Ignite Easier or Burn Hotter

When I was a fireman I noticed many times that a fire will go nuts and get very hot if you hit it wrong with a mist of water. I always thought maybe the spray of misty water pulled fresh air right along with it. Maybe it was really the molecules splitting like you described and the hydrogen was burning...it makes sense.

My bulk dealer washes the coal before delivery. Sometimes it's raining the day of delivery. Very often, the coal is so wet that there's a stream of water also pouring off the end of the coal shute.

Most years, the coal in the bin is still wet for the first month (September) as I dig down into it, and then damp for October and November months. But, by sometime in December, the pile has pretty much dried out for the rest of the heating season.

I don't notice that the stove puts out anymore heat while the coal is wet, or when it's just damp, verses after it dries out.

Paul

Richard S. wrote:

Sunny Boy wrote:My bulk dealer washes the coal before delivery.

When I was delivering I've had people request dry delivery once.... keyword being once. I warned them.

When I lived on LI, my bulk dealer only delivered dry coal. I had to make sure the coal bin room was sealed up good before he started. And then I wouldn't open that door until the next day.

When I built the bin here I also made it so I could close it up good. Turns out that I didn't need to. Now, I stand in the bin doorway and push coal into the corners as it comes off the chute and I don't even need a dust mask on. Having dealt with both, I don't mind paying a little bit more per ton for washed and still wet coal.

Paul

The thermal dissociation of water into hydrogen and oxygen is highly endothermic (energy consuming, technically at the level of ΔH° = 55.8 kJ mol^-1). The concluding remark (last line) in this linked study concludes that:

This direct thermal decomposition of water is not feasible at an industrial level with present technology.

And within the body of the text this is found:

The water decomposition reaction is non-spontaneous except at higher temperature than turning temperature (4500 K)

4,500 degrees Kelvin is 7,640 degrees Fahrenheit. This means that getting more energy out of the water than you put into its dissociation into hydrogen and oxygen is not going to happen in a coal stove. (I assume here that non-spontaneous means endothermic, or energy consuming, until the "turning temperature" is achieved, at which juncture it turns exothermic (or energy producing)

https://www.eolss.net/Sample-Chapters/C08/E3-13-03-01.pdf

https://www.quora.com/Why-is-the-dissociation-of-water-an-endothermic-reaction

I was gonna say, even if you could separate the hydrogen and oxygen from water in a coal stove it would require energy to do that. That energy would be in the form of heat. Any heat gain from the separate components of said split water would "wash out" (no pun intended) the heat required to separate them in the first place. Net gain being zero.

Besides, we don't see the wood burners leaving their wood out in the rain. Probably because wet wood doesn't burn very good or produce very good heat.

We cannot violate "energy can neither be created or destroyed" law of physics.

Normally water is separated into hydrogen and oxygen by running DC current thru it. I used to do it high school and ignite the hydrogen lol. It impressed my friends hahaha.

Like I said, some people have issues getting their head around how it can work, with it being at first glance so counter intuitive.

Its the same process that occurs in a charcoal gasifier.....if you want higher BTU gas output, you feed steam or drip water into the gasifier air intake.....very well proven technique....and yes if you feed too much steam/water in you will start to quench the combustion.

Callum

I could see how dry steam, like the steam produced for a power station steam turbine would work.