[Gasification] Fluidised Bed Reactor

[Kevin C]

Dear Dan

Quoting Carefreeland at aol.com:

> Doug and all,
>     Would some sort of a high temp molecular cracker be  a good companion
> to create a quality gas from a fluidised bed? Possibly some  steam and / or
> preheated air.involved? Seems if you wrapped the exhaust back  through the
> hottest part of the flame in a reactor tube this can be  accomplished.
>     Sorry but I have been kinda outta the loop for a  while.

# Start by appreciating the two Fundamental Rules of Thermodynamics  
and Thermo Chemistry:
Fundamental Rule #1: You can't get something for nothing
Fundamental Rule #2: As a matter of fact, you can't even break even.

For example, the reaction
C + O2 --> CO2             (`1)
is strongly exothermic, and gives off about 14,000 BTU per pound of  
carbon that is oxidized.

If there was insufficient O2, and the C was only burned to CO, as follows:
C + 1/2O2 --> CO           (2)
then only abut 4,000 BTU would be released  per pound of carbon.

If we wanted to reverse reaction #1, we would have to put back 14,000 BTU/Lb C
OR, in the case of a gasifier, where the reaction
CO2 + C --> 2  CO         (3)
is desired, we would have to "put back"  energy as follows:
14,000 + 0 --> 2x4,000 + "X"
14,000 --> 8,000 + "X"
and it is obvious that "X" is 6,000 BTU, in order to respect  
Fundamental Rule #1

"Molecular Crackers" and "Catalysts" do indeed work, but only when the  
fundamental need to add or remove energy from a reaction is respected.  
As long as the "fundamental need for an energy balance" is respected,  
then many things are possible.

Best wishes,

Kevin

>
>     Dan Dimiduk