[Gasification] water injection of producer gas fired ic engines

[gasman]

Hello, Jim, Peter and All!


----- Original Message ----- 
From: "jim mason" <jimmason at whatiamupto.com>
To: "Peter Wilson" <petergwilson at gmail.com>
Cc: "Gasification" <GASIFICATION at listserv.repp.org>
Sent: Sunday, July 09, 2006 1:16 PM
Subject: Re: [Gasification] water injection of producer
gas fired ic engines


> On 7/8/06, Peter Wilson <petergwilson at gmail.com>
>wrote:
>>
>> Fascinating. Thanks for all of this - I now see that
>> it's better to inject the water into the cylinder than
>> to introduce it into the gas stream prior.
>> I see one problem though - if one uses a Kalle gasifier
>> (which use exhaust CO2 to reduce the heat of the
>> gasifier), then there may not be enough CO2
>> left in the exhaust to cool the gasifier down.
>> Interesting...
>>
>>
>
> well no, with water injection you are going to get
> more CO2 in the exhaust.  perfect exhaust is
> ALL CO2 and nothing else, remember. From my
> reading on the kalle, it seems the kalle uses the
> exhaust gas to mostly cool the nozzle tip, by
> diluting the O2 in the air blast. given that kalles
> run on charcoal dust, the fuel is very dense, and
> the combustion zone if very small, thus is gets
> VERY hot. the swedish gengas books says they
> will melt the nozzle and grate in about three
> minutes if the ic exhaust gas recirc is not
> established immediately on start.
>
> and also, they claim noticable efficiency increases
> by the CO2 recirculation of the kalle, but no
> numbers are given. this makes sense, as CO2 is
> being reintroduced for further reduction to CO.
> less C is needed from the combustion of more char,
> thus reducing the consumption of char in the gasifier.
> also, the less char that needs to be oxidized to make
> CO2, the less heat that is generated, thus solving the
> coriginal problem.  two nice gains.  thus why the kalle
> had such a long run it seems.
>

¤¤¤ And as I pointed out on 3 July 2006, The incoming
       exhaust gas under pressure works as an injector,
       scooping up the coal-grains from the bottom of
       the outlet cyclone, blasting them together with
       some "new" gas up to the air-intake above the
       nozzle the diaphragm.
       All these three properties together gives it an
       mileage advantage of ~20 %.
¤¤¤

> and no, this is not a perpetual motion machine.
> there still needs to be oxidation to produce the
> process heat that heats the charcoal so
> the reduction reactions can happen.  those again,
> are:  C + CO2 =  2CO   and   C + H2O = CO + H2.
>
>
> relatedly, has anyone here yet to notice that all
> this fuel we are burning to make process heat to
> run the gasification reaction is  largely the same
> thing happening next door in the ic motor?
>
> on gasifier/ic rigs, it seems somewhat silly to have
> two combustion areas, then waste most all the heat
> from one of them out the exhaust (i.e the ic exhaust).
> getting most all the heat from the ic exhaust
> back into the gasification reduction zone for process
> heat seems  obvious. it is odd that the kalle is the only
> one that is really doing this. there is lots of heat
> coming out the exhaust of an ic motor.
>

¤¤¤ In principle yes, but as the exhaust is ~17% of
       the primary air intake, it has not much significance
       as the small exhaust  tube from the main exhaust
       line is uninsulated!
       Additionally, the extra CO2 is used for COOLING
       the process  by chemical means...
       This is useful in a charcoal gasifier, and USELESS
       in a wood gasifier.
       Indirect recouping of heat is another matter!
¤¤¤

it seems there is a gasifier/ic rig design floating out
in possibility hat is somewhat of a two vessel fluidized
bed sort of design. the ic engine is the combustor
making the heat. the gasifier uses the ic exhaust
heat as process heat for the gasification reaction.
maybe both as heat transfer, as well as direct exhaust
gas contact, or CO2 blast.
basically a two vessel, CO2 blast gasifier, with process
heat from the ic motor. given the exhaust velocities,
it seems to beg to be a fluidized bed or suspended flow
type.  run it on packed sawdust.
>

¤¤¤ Exhaust temperatures are too low even at the exhaust
       manifold, not to speak of transported further away.
       So the exhaust heat is only useful for preheating the
       prinary air, and aiding in fuel preheating and drying
       with condensation + out.
       (Wood gasification!)
¤¤¤


basically a two vessel, CO2 blast gasifier, with process
heat from the ic motor.  given the exhaust velocities,
it seems to beg to be a fluidized bed or suspended
flow type.  run it on packed sawdust.


¤¤¤ Separated from the gasification process in a
       different vessel, this can assist drying the
       fuel + condensing in a cooler..

       STOP DREAMING of ANY  too cold CO2 blasting!

       Gasification NEEDS  >1200 degrees Celsius,
       and that means oxidation heat!

       For wood gasification, which inherently produces
       too little heat energy, all available  INDIRECTLY
       delivered recouping sources are very welcome
       indeed!
       For preheating primary air, before the gasifier-internal
       heat-exchanger, and the rest for "hard drying" the fuel
       (torrefying), meaning to get out the most of the chemical
       water BEFORE pyrolysing, oxidation(combusting with
       CLEAN  preheated air) and gasification.
       Even the torrefying needs beefing up by recouping heat
       from the leaving raw gas inside the gasifier!
¤¤¤

> This  still wouldn't get rid of the always annoying N.
> but it would to recycle much of the ic waste heat,
> well as recycle much of the C, so that less char is consumed.


¤¤¤ Only with charcoal, and charcoal does not need any heat
       recouping! The C in CO2 is welcome!
¤¤¤

Max


has anyone built such a thing?   does this exist?

j



>
> Peter
>
>









-- 
----------------------------------------
Jag använder gratisversionen av SPAMfighter för privata användare.
 2495 spam har blivit blockerade hittills.
 Betalande användare har inte meddelande i sin e-post.
Hämta gratis SPAMfighter här: http://www.spamfighter.com/lse