Robert

IFB stainless liner school rocket stove
IFB stainless liner school rocket stove skirt detail

On a recent trip to Haiti, I completed the first prototype of a new school rocket stove. This one has a 330 stainless steel liner, 2½" insulating firebrick walls, and galvanized steel outer shell. The skirt is 304 stainless inside, 1" ceramic fiber walls, and galvanized steel outer. The mouth and firebox are 6½" x 6½". The pot is 40 qts with the top diameter about 1/4" larger than the diameter near the bottom, and is imported. The locally available spherical bottom pots made skirt construction extremely difficult. We hope to someday produce this stove in quantity at a combined vocational school/stove factory.

steam pan charcoal stove
steam pan charcoal stove side bottom view
steam pan charcoal stove bottom with perforated lollipop air control
perforated lollipop air control closed

In my continuing quest to use readily available manufactured materials for stove construction, here is the steam pan charcoal stove with "perforated lollipop" air control. It is a 1/6 size steam pan (roughly 6" x 7" x 4" deep) inside a 1/2 size (roughly 10" x 12" x 6" deep) with 1" ceramic fiber board insulation between. The charcoal chamber is lined with expanded stainless steel to extend the life of the inner pan and improve air flow. Army surplus D rings are used for pot supports. Threaded rod for legs. It can be easily disassembled for repair. It has a small charcoal capacity like the BURN's Jikokoa (formerly Tank).
I plan to eventually build a two burner version in a full size steam pan.b

ammo box stovetop oven outer with insulation and stainless lining
ammo box stovetop oven inner with gasket and stainless splash plate
ammo box stovetop oven with door removed
ammo box stovetop oven complete

On my trip to Haiti in March 2016, I finished the ammo box stovetop oven. It is made with two ammo boxes, ceramic fiber board insulation, some stainless steel sheet, and various hardware. The oven chamber is 13" x 13" x 5". I plan to add split firebricks on the floor for use as a pizza oven. It fits on a household rocket stove but could be used over virtually any heat source.

sink charcoal stove
rebar inverted pyramid charcoal stove

The inverted pyramid rebar stove is ubiquitous in Haiti. Lots of radiation and convection away from the pot. No air control. Pot is often placed directly on the charcoal which quenches the charcoal and interferes with good radiative heat transfer.
I cut up a scrap stainless steel kitchen sink, built a sheet metal outer box, put in 1" of ceramic fiber board insulation, and added legs and pot supports. The inverted pyramid grate will have the legs shortened and be placed inside the "sink". A slide gate with sets of progressively smaller holes will be added to the "drain" for air control.

toaster slot briquette stove liner with grate
toaster slot briquette stove liner with door flaps
toaster slot briquette stove liner with door flaps front
toaster slot briquette stove front one door flap open
toaster slot briquette stove doors open

TOASTER SLOT BRIQUETTE STOVE
I have been designing some briquette burning stoves for El Fuego del Sol, which is making square fuel briquettes from paper, cardboard, and sawdust in Port au Prince, Haiti:
https://sites.google.com/a/elfuegodelsol.com/elfuego/
The stoves are loosely based on rocket stove principles. My latest stove is inspired by the toaster. Briquettes are like thick pieces of bread. For good combustion they need to be surrounded by air and slightly separated from each other and the liner wall. This design holds 4 briquettes in two vertical slots of expanded stainless steel. As they burn down, new briquettes are added through insulated swinging door flaps.
Wrapping new briquettes in a sheet of paper before insertion ensures quick ignition and minimal smoke production.
Air comes in the front and bottom and can get to all sides of the briquettes. The insulated doors block much of the radiant heat from the upper briquettes from escaping out the front and keep briquettes from rolling out of the stove.
The liner will be surrounded with insulating bricks and have a galvanized steel outer shell. There will be a pot support frame and sheet metal pot skirt at the top.
The concept should also work well with round briquettes and dung fuel.

wocket stove with wok
wocket stove galvanized interior
wocket stove galvanized finished
wocket stove stainless interior
wocket stove stainless finished

Wocket Stoves

Sustainable Berea wanted me to build them a couple of rocket stoves to be used with woks for stir frying lunch during their local Solar Tour.

I bought a couple of 14” steel woks for cooking and a 14” stainless steel wok and a 13 quart stainless steel bowl for skirts.

I used the stainless bowl with 4“ galvanized steel stovepipe and the stainless wok with 4” stainless steel stovepipe.

I used 4” Tees for combustion chambers, 2x4 metal stud piece for feed chamber and expanded metal for grate and back wall of combustion chamber.

I used 6 gallon metal buckets for the shells.

I put a 1” thick piece of ceramic fiber board under the bottom of each Tee.

I put an 8” stovepipe outside of the galvanized steel riser to reduce overheating and insulated between it and the bucket with fiberglass insulation.

I insulated around the stainless stovepipe with two 1” pieces of ceramic fiber blanket and between the ceramic fiber and the bucket with fiberglass.

http://www.trust.org/item/20130723104434-3k5zt/

Clean stove cooks up power alongside food
Source: Thomson Reuters Foundation - Tue, 23 Jul 2013 10:44 AM

tractor jack briquette press

I was finally able to complete my tractor jack briquette press on a recent trip to Haiti. I started it in the spring but had to load it into a shipping container in May before I could complete and test it. It uses a 3 1/2 ton (3.2 tonne) 48" (122cm) tractor jack. About 30" (76cm) pressing cylinder, 3" (76mm) diameter PVC . Two 3/4" (19mm) threaded rods for tensile members. 4' x 6" (10cm x 15cm) rectangular steel tubing base. Shouldered hole in bottom to hold cylinder base while allowing briquette ejection. 4" x 4" (10cm x 10cm) square steel tubing top. Wood frame. Removable steel plate covers ejection hole for pressing.
The long stroke allows for production of multiple briquettes at once with plastic disc spacers.
The current design produces pucks. Holey briquettes are possible with some modifications.

On a recent trip to Haiti I was finally able to construct my CharBowl(tm) charcoal stove. It uses two nested stainless steel bowls (5 quart and 8 quart (4.7 liters and 7.6 liters))for durability and reflectivity with castable insulating refractory between them to reduce conductive heat losses. It has a 6.5" (16.5cm) dia cast iron grate for durability. It has a secondary air pipe to reduce CO emissions and increase heat output. The secondary air outlet pipe is 3/8" (10 mm) nominal (ID 0.493" 12.5mm; OD 0.675", 17mm) black iron with a Tee fitting on top to keep charcoal from dropping into it. 3/4" NC 10 (19mm 2.5) machine threads were cut over the pipe threads. This allowed the use of a split nut and flat washer inside and outside the bowls to hold the bowls together. The elbow is 3/8" to 1/2" . The inlet pipe is nominal 1/2" iron (ID 0.622" 16mm; OD 0.84", 21mm). The bowls sit on a stock pot base for stability and primary air control. (I couldn't get my hands on the stainless pot I really wanted to use for the base. I'm planning to build another with such a base now that I'm back in the States.)
I hope to get some testing done on my second prototype.
It can be used as the base of a TChar stove.

Robert V. Lange, February, 2011

Robert Lange, and the team from the ICSEE has been working in cooperation with the local Maasai leadership to bring both improved cookstoves and improved light and radio access to their people, as well as the training to install and repair their own stoves and PVC systems.

This project does a great job of teaching the women of the Maasai tribes to build their own improved rocket style stoves using local materials, and relatively small sections of steel and rebar to improve the durability of the local ceramic brick. The women are clearly proud of their new stoves, and their ability to repair, and move the stoves as needed, and even better than that - the neighbors are jealous and motivated to learn and build as well.

More information is available on their web site: http://www.maasaistovessolar.org

More information about the project methodology, and other ICSEE Projects can be found on the ICSEE web site:
http://www.the-icsee.org/projects/africa/villageprojects.htm
and the Villages Project web site: http://www.villageprojectsint.org/

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