[Bioconversion] Plasma Arc -- super critical water -- all the nut's and bolts found here --

[Peter Singfield]

All the formulas -- the pathways -- the energy equations -- endothermic and
exothermic -- everything including the proverbial kitchen sink!!

http://engnet.anu.edu.au/DEresearch/solarthermal/pages/pubs/MunzingerSol06.pdf

Near paper -- and valid suggestion to use solar energy for your super
critical water conversion needs.

Hmm -- one could also do this for "arcing" to -- hey -- sun to portable
fuels!!

Peter/Belize


************examples************

C + 2H2O + Energy = CO2 + 2H2 (4)

The energy input needed for this reaction is 178kJ/mol and this can
potentially be provided by a high temperature solar thermal system. The
resulting hydrogen in the product gas then can be burned/oxidized:

2H2 + O2 = 2H2O + Energy (5)

giving off 572 kJ/mol of carbon. 

Compared to just burning coal (carbon)

C + O2 = CO2 + Energy (6)

giving off 394kJ/mol. 

The solar enhanced gas contains 178/572 = 30% solar energy from the
thermochemical conversion, it can also be applied in much more efficient
conversion processes such as fuel cells or combined cycle power plants. 

Other hydrocarbons are gasified according to:

CnHm + 2nH2O + Energy =¨nCO2 + (m/2 + 2n)H2 (7)

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Since hydrogen storage itself is still a critical point, it is useful to
consider the conversion into easier
storable media. Looking more closely at the gasification reaction, it is
actually two steps:

C+H2O +Energy = CO + H2 (176kJ/mol) 

CO + H2O + Energy = CO2 +H2 (2kJ/mol) 

If one stops after the first step (which is the energy intensive one), the
CO plus H2 mix, called syngas, is the feed stock for making Di Methyl Ether
(DME) which can then be transformed into a diesel substitute.

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3. REACTOR TECHNOLOGIES
3.1. Fixed-Bed Gasification

Fixed bed gasifiers involve reactor vessels in which the biomass material
is either packed in or moves slowly as a plug, with gases flowing in
between the particles. A number of different reaction zones can be
identified in such reactors:

1: Drying Zone

Moist Biomass is heated up to about 200¢XC and the moisture is driven out.

2: Pyrolysis Zone

The temperature is increasing up to about 500¢XC and the biomass is
pyrolysed to tar-oil, charcoal and some gases.

3: Reduction Zone

Temperatures here reach from 500 up to about 800C. Hot gases from the
combustion react with charcoal and are reduced:

C + H2O = CO + H2 (4)

C + 2H2 = CH4 (5)

C + CO2 = 2CO (6)

4: Combustion Zone

The temperature is greater than 800C. Charcoal is burned with air or
oxygen, which are fed in through a grate, sometimes mixed with steam. This
produces the heat for the overall gasification process.