[Gasification] Difference between biomass and coal gasification

[Arnt Karlsen]

On Mon, 25 May 2015 08:37:05 -0300, Juan wrote in message 
<55630961.3090808 at umag.cl>:

> 1. You want to adapt a biomass gasifier to coal gasifier?

.."yes", as in adapt a coal gasifier to co-fire e.g. municipal 
solid waste.  I haven't fired coal yet, the closest thing this 
far was shredded tires, which of course left quite a bit of pig 
iron wire bits in my ash. ;o)

> 2. If you have high ash coal, you know the components of these ashes,

..only vaguely, I'm more interested in learning how much etc ash my
gasifier can handle, I have run it on pelletized sewer with ~60% ash
and minerals and ~40% biomass.

> as many inorganic can catalyze your reaction and behave in a better
> way. 

..yes, big massive pile of work there.

> 3. What is the calorific value of your coal, will be the
> subbitominosos type.

..I'm open for all variants there, e.g. the pelletized sewer did not
burn in free air, it needed bottled oxygen from a torch to light up,
and it needed to be fired "2.5 times" to burn out all the biomass
carbon, other than that, my gasifier, my flare and my flare fan 
(mower) engine ran fine on the stuff.  

> 4. Do you know which is the melting point of your ashes?

.."not yet", I use my ash as an "ash pile throttle" to control 
the size of my reduction zone and keep my gas reduction zone 
residency time low to prevent the CO -> CO2 reversal.

..I try to extract my gas at 1050 Celsius to maximize my gas fuel 
heat values, and I saw no significant ash melting.

> Juan Moreno
> 
> El 25-05-2015 a las 6:10, Arnt Karlsen escribió:
> >> Hi all,
> >> >
> >> >Thanks for the response, but I am once again stating my question
> >> >with some specifications.
> >> >
> >> >I am interested in coal gasification where coal used is with high
> >> >ash content and less reactive.
> >> >
> >> >Capacity of gasifier is around 30 Tons of coal per day and
> >> >technology is updraft fixed bed.
> > ..can this be modified to fit e.g. a 1 - 2 meter tall "battery
> > of Imberts" inside your current reactor vessel?  I haven't made
> > up my mind on the ideal sizes for my gasifier and I have a few
> > ideas I'd like to try out.
> >
> > ..regardless of sizes,  the hot section of my gasifier is going
> > to be about 1 to 2 meters tall, and I'd like to consentrate on
> > that rather on the other junk I need to test my ideas.
> >
> >> >If the reactor is operated at high temperature to crack any tar,
> >> >ash would come out in molten form (Not desired) as conditions
> >> >will cross ash melting point.
> > ..in my gasifier (75kWe-300kWth "V-hearth Imbert" with tar vapor
> > flare on top of the combustion zone "lens") I simply draw my tar
> > vapors off my fuel hopper that sits on top of my combustion zone
> > "lens", pipe it and some air straight down into my flare and use
> > the combustion zone "lens" to ignite and burn my tar vapors, this
> > also agitates and stabilizes the Imbert combustion zone "lens."
> >
> > ..for updraft, this becomes a little harder, as you have tar vapors
> > "all over" your gas, and not just in your fuel hopper.
> >
> >> >So in this sense, tar generated after gas cooling be recycled into
> >> >gasifier?
> > ..your tar vapors generated in your gasifier and then
> > condensed into tar droplets when you cool your gas.
> >
> > ..with your upstream gasifier, you have to clean your
> > entire product gas stream, how much does that cost?
> >
> > ..with my setup, I keep my tar vapors away from my product gas,
> > instead I use them to heat, agitate and stabilize my "Imbert"
> > combustion zone, and then to fuel it, around 2/3 to 4/5 of it.
> >
> >
> >> >Regards,
> >> >
> >> >Saiteja
> 


-- 
..med vennlig hilsen = with Kind Regards from Arnt Karlsen
...with a number of polar bear hunters in his ancestry...
  Scenarios always come in sets of three: 
  best case, worst case, and just in case.