Home Page
   Articles
       links
About Us    
Traders        
Recipes            
Latest Articles
Pumping gas...
Page Previous  1, 2, 3, 4, 5, 6
 
Post new topic   Reply to topic    Downsizer Forum Index -> Energy Efficiency and Construction/Major Projects
Author 
 Message
Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Thu Jan 29, 15 9:24 am    Post subject: Reply with quote
    

What happens if you overheat it?
The difference is that you are trying to make charcoal, which you do by burning or boiling off everything else: it doesn't matter how much of the eelse that you burn to keep it hot enough.
Whereas I am trying to harvest the eelse, and I think I'll be needing to use an external heat source: every joule that escapes is a joule that I'll have to replace.

dpack



Joined: 02 Jul 2005
Posts: 45377
Location: yes
PostPosted: Thu Jan 29, 15 11:51 pm    Post subject: Reply with quote
    

would a kiln drum inside a slightly bigger(insulated) drum that is heated in a rocket stove style by a combustion chamber with a choke valve to control the airflow and a chimney to drive the airflow be a place to start ?

if the "remains" in the pyrolosis drum is charcoal that could be at least part of the fuel for the next batch

ps another option might be a "hot tube" (or tubes)in a drum of woodchips again powered like a rocket stoveand insulated on the outside

i recon play about at the 25 to 50 ltr scale and see what works then refine method then try bigger ,too small will have too many heat losses etc

50 gall oil drum scale might be a better experimental size

clay is cheap and mixed with fibreglass makes fairly a good fire cement for filling gaps etc

Mistress Rose



Joined: 21 Jul 2011
Posts: 15539

PostPosted: Fri Jan 30, 15 8:04 am    Post subject: Reply with quote
    

If it gets too hot the metal of the kiln glows red and distorts; we are talking about those sorts of temperatures. Using a retort kiln, which is pretty well what Dpack is talking about, you can in theory take the gasses you are producing and cool them to use the various chemicals coming off. The only time we have ever had problems with getting the temperature high enough was when we were trying to make wood tar and we had a container that was about a foot or so cube. it just wasn't really large enough to hold the heat, and it wasn't made so we could increase the pressure as we should have done.

To break down wood by pyrolysis needs quite a high temperature, and even with no or very little air, you are still talking about things getting pretty hot once it get going. The initial burn is usually carried out using wood to get the whole thing up to temperature.

dpack



Joined: 02 Jul 2005
Posts: 45377
Location: yes
PostPosted: Fri Jan 30, 15 4:13 pm    Post subject: Reply with quote
    

the "tubes"thing i tried to describe is a bit like a steam engine boiler but with woodchip where the water would be .

having thought about it the problem of removing the residue from between tubes might require a bit of experimentation and planning to work well.

another slightly different option would be to pipe the hot combustion gasses( balanced or slightly reducing flame)directly through the wood chip a bit like air into a forge fire in a box

i want to play now ,but i cant see it being popular in a city terrace yard

Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Sat Jan 31, 15 9:31 am    Post subject: Reply with quote
    

dpack wrote:
the "tubes"thing i tried to describe is a bit like a steam engine boiler but with woodchip where the water would be .

Yes, I had had a similar idea.

Quote:
having thought about it the problem of removing the residue from between tubes might require a bit of experimentation and planning to work well.

The residue /should/ be charcoal. It shouldn't be too hard to tip out if the drum is not too big. Few big tubes rater than many small ones.

Quote:
another slightly different option would be to pipe the hot combustion gasses( balanced or slightly reducing flame)directly through the wood chip a bit like air into a forge fire in a box

Instinctively, I feel that would not work, but logically, I cannot think why not.

Quote:
i want to play now ,but i cant see it being popular in a city terrace yard

If you've got a condensor on the exhaust, then you shouldn't be producing much smoke... perhaps also bubble it through something? I was thinking biodiesel soap: see if anything reacts with anything.

Post new topic   Reply to topic    Downsizer Forum Index -> Energy Efficiency and Construction/Major Projects All times are GMT
Page Previous  1, 2, 3, 4, 5, 6
Page 6 of 6
View Latest Posts View Latest Posts

 

Archive
Powered by php-BB © 2001, 2005 php-BB Group
Style by marsjupiter.com, released under GNU (GNU/GPL) license.
Copyright © 2004 marsjupiter.com