burn wood chips ?

[Wood wasp]

I can confirm above re explosion... Let my stove die down to pile of embers, load up with dry wood but leave shut down and I'm pretty much guaranteed a bang when it finally catches enough to light the gases.

[cornish wood burner]

I can confirm above re explosion... Let my stove die down to pile of embers, load up with dry wood but leave shut down and I'm pretty much guaranteed a bang when it finally catches enough to light the gases.

 

Exactly. Now try the same in a 3 MW boiler. Now that's a bang

[aspenarb]

I suppose you are inadvertently turning you woodburners into gasification plants. They run generators on those in remote area`s of the states.

 

[ame]

[/ame]

 

Bob

[Wood wasp]

How efficient are those gasifier plants?

[openspaceman]

I suppose you are inadvertently turning you woodburners into gasification plants. They run generators on those in remote area`s of the states.

 

 

The chap in Redhill should be running his lister with his gek now, also look out for the german unit from Entrade, both running on pellets.

 

During the war the Scandinavian countries made extensive use of gasifiers , initially on charcoal with Kalle types and later on whole wood chunks in Imbert downdraught devices.

 

Conversion efficiency is measured by the calorific value of the cold gas entring the engine compared with the fuel value of the wood, over 80% cold gas efficiency is possible but the best modern devices are around 75%.

 

The main problem isn't efficiency of conversion but cleanliness of the gases resulting. The idea is to keep the reactor hot enough to convert the wood into carbon monoxide and hydrogen with as little nitrogen as possible. In fact you end up with various pyroligneous species that tend to gum things up and shorten life of engine oil or get filtered out and cause a disposal problem.

 

With pre processed fuel (like pellets) and modern feedback using sophisticated electronics (the sort of things common on modern engines) it looks like they are getting close but bear in mind wood fuel is going to be 5 times more bulky than petrochemical fuels.

 

Long term the future is more likely to be synthesis of simple liquid fuels like dimethyl ether.

[renewablejohn]

Been looking all over for a Kalle type gasifier without any joy for the last 5 years then on holiday in Sweden found one in a motor museum. Unfortunately the guy would not sell so still searching.

[openspaceman]

Been looking all over for a Kalle type gasifier without any joy for the last 5 years then on holiday in Sweden found one in a motor museum. Unfortunately the guy would not sell so still searching.

 

They were an early type and limited by the fact they needed a good quality charcoal with the extra work and thermal losses involved in making it. Not so much a problem if the char making is a by product of another heat making device. Because of the higher energy fuel it required an early form of exhaust gas recirculation to keep the hearth temperature down.

 

Another drawback was that CO low flame speed limited engine speed compared with the Imbert whole wood type which had the benefit of hydrogen to propagate the flame front faster. Also the higher proportion of nitrogen would have been a drawback. The benefit would have been lower tar contamination of the engine and lubricant.