RE: GAS-L: Gasification for combustion?

[Weststeijn A <A.Weststeijn@epz.nl>]

Dear Martin,

You write:
> Some of you want to gasify biomass to burn the gas for heat generation for
> a steam cycle. I can't see the advantage
> compared to biomass combustion. So, why do you want to gasify the biomass
> previously?
> 
It is all in the end  result of fuel efficiency and finances. And in the
equipment available.
 
Sometimes the equipment is especially designed for the purpose (dedicated). 
Sometimes it is existing equipment, now partially used for this new purpose.

If you just want heat, like for home heating, you don't need to gasify, much
less need a steam cycle.
If you just want to generate elec. power, you can simply burn
biomass-derived gas in a gasturbine or -engine, also without a steam cycle.

However, every equipment combination has it's own set of efficiency
potential, it's own set of practical limitations (to have it work
continuously and reliably) as well as it's own price tag.

If biomass is gasified, it can be used in a specially newly designed gas
turbine, or gas engine, but also co-fired in an existing natural gas boiler
(raising steam) or natural gas fired gasturbine (with steam raised from the
exhaust heat). You can't do that by burning biomass directly.
Some of these scheme's have a particularly attractive fuel efficiency and
look promising for further development.
If you elect to include a steam cycle, there are simplier and ultimate
efficient designs for that as well.

So, next to burning biomass directly, the route through gasification does
have its own set of advantages and applications.
Those advantages then pay for the additional step (first gasifying, then
burning the gas).

There really is a large matrix of conversion scheme's and existing practical
working conditions, not to mention the variety in bio fuels.
To pick the best combinations is a skill under development.
If I am not mistaken, judging from your Email address, your university in
Essen is doing it's fair share!

Andries Weststeijn


> Dear all,
> 
> I have been following your discussion for a while and there is one thing
> I can hardly understand. Some of you want to gasify biomass to burn the
> gas for heat generation for a steam cycle. I can't see the advantage
> compared to biomass combustion. So, why do you want to gasify the
> biomass previously?
> 
> Regards
> Martin Adorni
> The Gasification List is sponsored by
> USDOE BioPower Program http://www.eren.doe.gov/biopower/
> and PRM Energy Systems http://www.prmenergy.com
> 
> Other Sponsors, Archives and Information
> http://www.nrel.gov/bioam/
> http://www.crest.org/renewables/gasification-list-archive
> http://solstice.crest.org/renewables/biomass-info/gasref.shtml
> http://www.crest.org/renewables/biomass-info/
> http://www.crest.org/renewables/biomass-info/carbon.shtml
> 
The Gasification List is sponsored by
USDOE BioPower Program http://www.eren.doe.gov/biopower/
and PRM Energy Systems http://www.prmenergy.com

Other Sponsors, Archives and Information
http://www.nrel.gov/bioam/
http://www.crest.org/renewables/gasification-list-archive
http://solstice.crest.org/renewables/biomass-info/gasref.shtml
http://www.crest.org/renewables/biomass-info/
http://www.crest.org/renewables/biomass-info/carbon.shtml