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Wood Gasifier Steam Engine

Use waste heat of wood gasification to run a steam engine.
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When a plasma gasifyer turns trash into syngas, the heat of the syngas is used to generate steam for a steam engine, which generates the electricity needed to create the plasma (and then some).

All descriptions of wood gasifiers that I've read seem to indicate that if the gas is to be used to fuel an internal combustion engine, it is cooled first... the heat is considered pure waste heat. Why not use the gas's heat to drive a steam engine? It will be cooled just as much, and we'll have generated some energy as a useful byproduct.

goldbb, Mar 05 2009

Enhanced Sequestration and On-Farm Energy Production http://www.scbiomas...ations/Agrichar.pdf
"The pyrolysis process also yields bioenergy in the form of hydrogen gas, oils, electricity and/or heat" [steam_cannon, Aug 03 2009]

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       People are thinking about this. In the process of producing Biochar (also known as Agrichar or simply charcoal), researchers are looking to develop systems that gasify organic molecules in plant matter leaving behind charcoal while at the same time taking the waste heat and using it to generate electricity.
steam_cannon, Aug 03 2009
  

       So how is the heat energy created by this process greater than the input energy?   

       Whilst it may well be practical to use the waste heat, you won't generate enough power from it to sustain the process.   

       Or do you intend using some of the fuel created by the process?
Twizz, Aug 03 2009
  

       // Whilst it may well be practical to use the waste heat, you won't generate enough power from it to sustain the process. //   

       The process of producing wood gas or syngas produces waste heat that could be used for home heating or for running some type of thermal engine like the poster describes.   

       // So how is the heat energy created by this process greater than the input energy? //   

       I'll try to give you a good answer for this... You see, it's not creating energy, the energy is from the sun. A plant stored the energy in the form of biomass and solar energy is released in the form of fire. In the wood gas reaction, some of the material is reacted and some of it is piped off as a gas to be reacted at a later time.   

       To understand this, think of a fire. A fire burns from the coals. The flames you see above the fire is wood gas. If this gas is separated, it can be burnt at a later time. And the process still creates waste heat that could be used for other things.
steam_cannon, Aug 03 2009
  

       Or to put it another way, fire is exothermic
BunsenHoneydew, Aug 04 2009
  
      
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