Re: GAS-L: maximum pressure and the wooden "battery"

[Arnt Karlsen <arnt@c2i.net>]

On Monday 04 February 2002 18:37, Peter Singfield wrote:
> Arnt --
>
> Metals oxide reduction/oxidation cycles are very well established!
>
> Thermite is a classy example -- iron oxide & aluminum
>
> So -- steam/iron = iron oxide + H2
>
> Aluminum and iron oxide = aluminum oxide -- pure iron -- and a lot of
> heat.

..yeah, I know thermite.  
I thought of "tin" as the wavy roofing kinda thin steel sheets.  ;-)

> The problem is always reducing the oxide back to the pure metal -- in
> this example -- reducing back to aluminum.
>
> But in the tin molten metal case -- it is "good"
>
> Try getting rid of the oxide in aluminum with any kind of efficiency!

..is how we use hydropower to cook aluminum up here.  ;-)
http://www.google.com/search?hl=en&q=soderberg+aluminum+Norsk+Hydro&btnG=Google+Search

> Further -- the "chemical" required -- CO -- is exactly what we have
> in our pocket!
>
> This reaction is very controllable. And runs to completion --
> extremely high purity H2 requiring no further purification -- and at
> extremely high efficiencies.
>
> Your carbon cycle is a nightmare -- comparatively. Sure -- it is

..so I handle nightmares just fine.  ;-)

> there in huge gasifiers -- doing a "little" -- as in "maybe".
>
> The tin metal bath is very positively reversible -- over and over --
> under very compact conditions -- and very energy neutral.
>
> >...which can be rewritten:
> >
> >H2O + Sn + 2 CO + SnO2 <-> SnO2 + H2 + Sn + 2 CO2
>
> Sure -- if one puts CO there during the "steam" cycle -- but why in
> the world do that!!
>
> It is a dual cycle deal Arnt -- you mean you really missed that??

..you saw my "<->" ?  ;-)

> Cycle one:
>
> Pure tin -- pass through pure steam -- result -- pure H2
>
> There is no problem producing pure steam.
>
> You turn off the steam well before H2O no longer reacts with Zn -- so
> no H2O crosses over.
>
> Ergo -- no H2O contaminating the "pure" H2 product.
> 
> Cycle Two:
>
> Once a set amount of ZnO2 is reached in the bath -- you turn off the
> steam -- and pass through the gas product that has been stripped of
> H2 in the membrane separator.
>
> The feed gas that is used to "reduce" the metal oxide back to a pure
> metal is the exhaust from the membrane separator.
>
> (The feed gas to the membrane separator can be product from a biomass
> steam reformation device -- or from even a biomass partial combustion
> gasifier)
>
> This "gas" exhaust from the membrane separator can be a combination
> of atmospheric (mostly N2) gas, residual H2, CO2, CO.
> 
> The ones we do not want there is O2 or H2O -- but small levels will
> not effect this reduction to a great extent anyway! There is no need
> to make the entire metal bath pure -- just to recover sufficient ZN
> from ZnO2 to repeat a cycle.

..dynamics, agreed.  Zn=zinc, Sn=tin.  It is tin?

> The CO reacts with the ZnO2 as above -- reducing the oxide to pure
> tin again -- the rest of the gasses pass through. Some residual side
> action due to contaminants of O2 and H2O may create new ZnO2 -- but
> the net result will be a lot of the ZnO2 back as Zn. And a little
> extra H2 at the exhaust.
>
> The Gas exhaust products -- still containing some hydrogen (and some
> CO) as well as the rest -- can either be used as a very low value
> fuel for the catalytic converter -- or passed through the membrane
> separator again --
>
> What is the purpose of all this??
>
> Maximizing production of H2 at extremely high product efficiencies to
> run an H2 fuel cell!!
>
> OK -- I've showed you mine -- using a tin bath --
>
> Now -- you show me yours -- using a hot charcoal bed?? Show me how
> you can maximize pure H2 using a hot charcoal bed??? And at high over
> all efficiencies!!


..I do _not_ want to maximize H2.   H2 is like vitamin C rice; an 
avocado or orange every 3'rd day fixes that vitamin C problem, and 
provides a diet change that "can be looked forward to".  
Ok, H2 and genetic wizardry is sexier when reeling in R&D funds.

..I want to maximize _total_fuel_system_efficiency_.