Fw: Dan on "Coal cooking summary"

["Ron Larson" <ronallarson@qwest.net>]

Stovers:

 

    I believe that Dan intended this to go the full list. 

 

    I think that Coal is a bit off the list general area of discussion - but that it was good we had the chance (so Thanks to Tami).  Not much likelihood that the world will turn voluntarily from wood to coal.

 

Ron

 

 

----- Original Message -----

From: Carefreeland@aol.com

To: ronallarson@qwest.net

Sent: Sunday, March 03, 2002 10:25 AM

Subject: Re: Coal cooking summary

In a message dated 3/3/02 7:42:51 AM Eastern Standard Time, ronallarson@qwest.net writes:

> Replies in text

2.   Strategically placed charcoal rather than wood under the coal might
assist in the coal-ignition process.  The gases and flames from the charcoal
MIGHT (no experience) be a good way to start the coal.  The practical
problem in the field is having charcoal - more expensive than wood.  If this
would allow a fire start without so much cook's time spent in supplying air,
it should be accepted quickly.

      > You are absolutely right Ron. Most of the charcoal to used to start coal is derived first from a dying wood fire.  The coal is added and both air intakes opened once the temperature of the stove is up. Coal dust and fines are used first, increasing particle size later. Largest chunks saved for overnight.
      > I practiced much of this a hundred miles or so southwest of you in an old historic house in Cripple Creek Colorado (elevation 9595ft).  The coal burner was the only heat in the house and I was the family fireman. We often had heavy frost or snow in June when we opened the house for summer visitors.  I was sad the coal burner was scrapped before the house was sold by a family friend.

3.  The "juntos" geometry being explored by Paul Anderson seems ideal to me
for starting the coal - with the coal combustor sitting above a pyrolyzer
section.  The flared gases emitted from the lower section can be arranged to
achieve their maximum temperature in the vicinity of the coal - maybe 15 to
20 cm higher.   The high flame temperature (as Dan notes below) will ensure
combustion of the gases released from the coal section, even while much of
the heat is initially used to heat up the coal prior to it ignition. (Any
heat escaping the coal region initially can still start the cooking
process.)  Paul's geometry in the coal region can also maximize the
reflection and insulation properties we have talked about. The extra height
noted by Dan is already present in the juntos geometry.

  > In older stoves this lower "can" was the ash pit under the grate.  A small wood fire was lit here and a primary air control metered the flame to build heat in the grate above. Remember that the efficiency of the wood fire was not the objective, so a simple side air entrance was sufficient 
   >    After the coal above ignited, the volatile gas was burned off with secondary air entering above the coal, swirling around the firebrick or cast iron sides for preheat. That was the evening cooking fire, warming the hearth, chimney and house.  Then later, the primary air was again the main control, and the secondary air entrance above the grate was cut back.  This glowing coke fire was for overnight
   > Hardwood like oak, hickory, and ash burn similar to coal, so I just build up charcoal during the day in these stoves. I have to top load more wood several times to do this, more than a coal fire due to lower density of woodchar.
  >As soon as the stove is hot enough, I need little or no secondary air to burn wood.  The wood gases are high enough in hydrogen to not require any extra air to burn clean unless the wood is damp.  I doubt that the building charcoal bed uses up as much primary oxygen as well due to lower temp. Maybe the draft is stronger with the additional woodgas flame compared to coal.

4.  Lastly, the charcoal produced in the lower region (from twigs, ag waste,
etc) has a place to be used in mixing with the coal ala presumption #2
above.   This lower section can be nothing more than a very small can -
almost zero cost.  The lower can size can be picked so that most of the
cooking and heating is done with the cheapest fuel.(presumed to be coal) in
the upper chamber.

  > Someone once again asked why we are discussing coal use on a Biomass Energy list.  A few months ago the conclusion was that we are here to serve anyone trying to REDUCE fossil fuel consumption and emissions. Many places in the world have nothing else available or affordable to use at this time.  Including my regional power companys.
   > We Biomass Energy people have always traded information with the fossil fuel users where mutual interests are at stake.  Unless one owns a struggling coal mine, this information can only help the environment, health, and the bottom line of fuel costs.
   > Tami Bond brought up the coal subject as a side note of studying cooking coal emissions and their terrible effects on the environment.  Any discussion of improving coal burning, adds to the somewhat lost knowledge of charcoal combustion.  I have a lot of success burning wood char overnight in my old coal stoves for greenhouse heating.
     > Speaking of building char in the greenhouse stoves for overnight. The temperature is forecast to drop below F10 degrees tonight, making this the coldest night of this mild winter. I have some hickory and plumb wood to char.  Maybe I'll see if there's any bituminous coal left up by the old barn from the barrel stove days.  Just a bucketfull would go a long way towards supplementing the heat late tonight. 
    > 20 Years ago I found a couple of tons of rock coal spilled beside a sharp curve on the highway. I hate to waste ANY fuel.  I have tender seedlings in the greenhouse, so I have to do what I must to protect them.  We MUST REDUCE coal use, but there is always a good reason to use just a little. Maybe I'll learn something new tonight.
    > Anybody wanting to experiment with a little coal can scavange coal and coke from any railroad track. Call it cleaning up the environment, just watch for the train.
       Good points Ron,
             Daniel Dimiduk    
      
     >  Writing from the middle of the eastern USA coal market, using coal energy to run my computer and light my house. We'll have to change that a little some day. ;-)