Jump to content
I Forge Iron

Charcoal Retort- very successful model pic heavy


Recommended Posts

I have stripped down my retort so that the pictures are self explanatory. this is a very, very sucsessful model.

 

Materials needed:

 

2 x 44 gal Drums(removable top type)

6 ft 4" pipe(1 x 2ft &  1 x 4ft ) 

1.5ft 6" pipe

some 1/2" square bar or what have you to make fire  grate

1 x 4-6" bell mouth

1 x 6" flange any type

a piece of plate 1/4" for base of drum

some tube, 2 x plumbers blocks , 2 x short lengths round bar to suit plumbers blocks , a piece of flat bar a bit longer than the circumference of the drum.

 

you need to drill 12 off 10mm holes 1" above the flange and 6off 3" above the flange

post-13949-0-69571200-1370539080_thumb.j

Link to comment
Share on other sites

more pics. Cut 1" and base off inner drum  & a 6" strip out off the side, roll with overlap and tack on one side, notch top lip to suit.

cut new base out of 1/4" plate , cut out 6" hole and make some holes to suit flange. fit one drum inside the other and ram/press fibreglass into the 2" gap.

post-13949-0-37994200-1370544426_thumb.j

post-13949-0-65905300-1370544477_thumb.j

post-13949-0-34627700-1370544535_thumb.j

post-13949-0-03400300-1370544591_thumb.j

Link to comment
Share on other sites

Loaded, to start up some sticks and to feed the fire some 40mm x 8mm strips, roll up some news paper slip it up the side and light!

pic 16 is 5mins into the burn. 17 is 5mins later.

Pic 18 is a crude but effective tilting device.

Pic 19 shows tilted drum heating up one side to speed up start of gasification.

post-13949-0-08689500-1370545759_thumb.j

post-13949-0-11609600-1370545825_thumb.j

post-13949-0-02023700-1370545894_thumb.j

post-13949-0-73759400-1370545965_thumb.j

post-13949-0-79110200-1370546023_thumb.j

post-13949-0-85707200-1370546066_thumb.j

post-13949-0-04824100-1370546137_thumb.j

Link to comment
Share on other sites

I'll use ab out one third of this to complete combustion.

Keep the top "hole around chimny" open to allow steam to escape.

Whem Smoke/steam changes from wtihe to grey- pack som e sand on the lid to cover hole and force smoke into firebox!

post-13949-0-06654800-1370546261_thumb.j

post-13949-0-72291600-1370546335_thumb.j

Link to comment
Share on other sites

After 45 mins the fire is self sustaining but keep the feed going for a whole hour and a half . Then leave it to finnish by itself. This design does not require capping or any other air shut off just leave to cool and empty.

This retort makes black powder grade charcoal!

It will burn for 3-4 hours and makes about 80 percent by volume charcoal. I have been amaised at the BTU output so we are now using it to heat 250l/day hot water and we want to try smelting aluminium on it soon.

Our retort takes about 4 x 20L buckets of wood.

Thanks for reading

post-13949-0-71159500-1370546595_thumb.j

Link to comment
Share on other sites

Nice design Ian. More complicated than the couple times I've done it but certainly effective. Please correct me if I'm wrong.

 

It looks like your venture burner tube burns the volatiles from the wood's pyrolization with intake air along the horizontal tube. You  initiate the burn with a fire in the horizontal (air intake). Once it's up to working heat, pressure drives the volitile gases into the burner through the holes around it's wider circumference. At which point it becomes a self sustaining process.

 

Pretty slick Ian. The wood being processed is isolated from fresh air so you don't lose any through combustion and it's unlikely to get so hot as to outgas carbon, C2, and burn it.

 

Well done, Mate.

 

Frosty The Lucky.

Link to comment
Share on other sites

Hi Frosty, the horisontal tube is a fuel  & air feed with a light grid down the middle(horisontal) air intake from below too.

Because it works similar to a rocket burner the fuel use is minimal,  depending on the wood used for char. self sustaning anywhere between 30 + 60 mins.

 

Otherwise you have it off pat. when its going this yhing roars and puts out a 3ft flame from the chimeny.

 

Ian

Link to comment
Share on other sites

I live in an upmarket residential area, country estates, type of environment-  dirty, smelly=not welcome. Thus the RTV is to prevent smoke(unburnt gas from the gasification) from sneaking out around the base flange. So far so good.

Link to comment
Share on other sites

Hi Frosty, the horisontal tube is a fuel  & air feed with a light grid down the middle(horisontal) air intake from below too.

Because it works similar to a rocket burner the fuel use is minimal,  depending on the wood used for char. self sustaning anywhere between 30 + 60 mins.

 

Otherwise you have it off pat. when its going this yhing roars and puts out a 3ft flame from the chimeny.

 

Ian

 

I believe I have the picture now. Thanks Ian.

 

Frosty The Lucky.

Link to comment
Share on other sites

  • 2 months later...

Hi Ian,

I'm very impressed with your retort design, I am looking to build something similar myself and I am curious about your reasons for the 4-6" bell mouth.

 

one question survey :)

a/   flue airspeed

b/   firebox size

c/   compensate for heat transfer

d/   none of the above

 

I am also wondering if there is any chance of going over temp while the wood is gassing fuel into the firebox? Did you consider a bypass to control this?

Link to comment
Share on other sites

Hi Ian,

I'm very impressed with your retort design, I am looking to build something similar myself and I am curious about your reasons for the 4-6" bell mouth.

 

one question survey :)

a/   flue airspeed

b/   firebox size

c/   compensate for heat transfer

d/   none of the above

 

I am also wondering if there is any chance of going over temp while the wood is gassing fuel into the firebox? Did you consider a bypass to control this?

C. But to improve heat transfer ie. Surface area over the initial fire to get gasification going. The only change I would make if I were to make a new one would be to substitute the 4'' round horizontal with a square tube

 

Ian

Link to comment
Share on other sites

  • 2 weeks later...
  • 3 weeks later...

more pics. Cut 1" and base off inner drum  & a 6" strip out off the side, roll with overlap and tack on one side, notch top lip to suit.

cut new base out of 1/4" plate , cut out 6" hole and make some holes to suit flange. fit one drum inside the other and ram/press fibreglass into the 2" gap.

Hi Ian,

 

I had some questions about your retort.  On the step above it would seem the outer drum keeps it's base though also has a 6" hole to accomodate the pipe and flange.  For the fabricated inner drum you welded 1/4" plate to it and this is bolted to both the flange and the outer drum?  Would something like this work also with a 55 and 30 gallon steel drums? 

 

What do you mean by "notch top lip to suit"?

 

Dan

Link to comment
Share on other sites

Hi Dan,

I'm sure those drums should work,     I just used 2 44's(it may be semanticsas I think that's english Gal=210L) :D  cause thats what I had. this way you'll have 2 bases so you might not need the "extra plate"  and if you do(when one wears out) then add the plate!

 

if you use 2 drums of the same size you need to cut the inner on e a bit shorter so it fits inside the other and slit the sideso you can "roll it up" a bit to reduce the diameter, I had cut the bottom off so that side was easy but you need to cut away a short piece of the top lip as it hampers the "bypass" . If you do it this way,You'll want to keep as much of the "tpt lip" as possible as it strengthens the inner drum and makes it safer. 

 

BTW. I cover/cap the top gap between the drums with mud(dirt & water)to protect and seal the fiberglass insulation(i do'nt want to breathe or replace the fiberglass) and it helps to make the retort pretty much "smokeless"

 

Ian

Link to comment
Share on other sites

Number 2 is the most similar, however the internal bell shape creates a form of "jet" by accelerating the hot air stream and mine roars like a jet aircraft with a long straight flame like out of a gas burner, and no need to bury the thing. But a good retort none the less.

 

I just need to figure out how to make/edit & post videos.

 

Ian

Link to comment
Share on other sites

I used a dual top one with a 4"hole and the lid with a larger hole  rotate untill the fit and the tec screw!

Is the dual top similar in function to the ventilation pipe that was seen in the 2nd video, which was added to prevent buildup of excess wood gas and allow steam to escape?  Is the inner lid smaller to fit the inner drum, then the outer lid with the larger hole clamped shut on the outer drum with both lids screwed together?  That then forces any escaping gases to go thru the larger hold which is then sealed later by covering w/ sand?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...