Notes from Paul Anderson
Gustavo has presented a very nice video of the use of a tall TLUD gasifier under a DUAL purpose stove frame (frame = stove structure without the heat source) that first boiled 5 liters of water in 12 minutes, and then converted into a plancha stove with chimney, cooking papusas (related to tortillas). Total cooking time 1 hour 45 minutes on one batch of wood chips/chunks (5237 grams) that yielded 1300 g of char. 25% weight yield of char. Probably could have operated an additional 10 minutes with pyrolysis fire and a slightly lower percentage yield of char.

Note: That is approximately 4000 g of fuel of pyrolytic gases (including moisture content that was probably near 15%). Any ash content (probably 1% of the raw fuel) remained in the char.

For a comprehensive resource for TLUD stoves, see Paul's web site: http://www.drtlud.com/
Nike React Element 87

Mike Barbee, January 2012

Jatropha curcas is grown as a living livestock corral and as a bio-fuel crop in several areas of the developing world. The seed from the Jatropha plant, as well as the oils are toxic to animals and to people. Ingestion, or skin contact with the oils of the plants, leafs and seeds is known to be toxic, and Mike does a nice job of documenting the current research about the plant in his paper: Summary of Literature on Jatropha Toxicity

It appears that there is NO RESEARCH on the toxicity of Inhaled jatropha either seed, stem, or cake (or pressed cake) form. This is an area of particular concern for me as we evaluate the effectiveness of using Jatropha as a fuel for cooking stoves.

to quote Mike:

There are no studies about jatropha the fraction of phorbol esters that may be present during pressing, composting, or burning. There is not enough information about the volatility to estimate the partitioning of oil that may contain esters in the air during the processing and application

The Key recommendation:
"It is recommended at this point, that those who are working directly with oil and seed cake during the pressing process wear protective eye and skin covering and, if possible, surgical masks to reduce inhalation."

Mussie T. (Lecturer at Mekelle University, Ethiopia), October, 2011

This is a Natural Draft Gasifier stove, that is designed with a central column of air that is designed to burn more common Ethopian fuels, e.g. coffee husk and saw-dust (cow dung binder) briquettes in addition to more conventional wood chips.

the air column is drilled on the surface so as to let additional primary air radially into the fuel at different stages to compensate for air clotting that can occur when run with small sized fuel as you go up from along fuel column. This helps the flaming pyrolysis from being air starved due to interlocking of fuel particles. In addition to that, closely spaced holes of relatively larger size were made near the top of the central air column to supply more hot post‐pyrolysis secondary air. The presence of two hot secondary air admission points is meant to supply enough air while keeping the stove short with reduced heat loss.

Once the stove has enough fuel, it is typically started with wood chips, or an accelerant to help the briquettes light, and then in all of the trials it burned without smoke until the fuel tank was filled with charcoal (typically between 60 and 90 minutes later). This is a biochar-producing stove, the stove does not efficiently combust it. Friability and the composition of the char depended upon the feedstocks.

For an excellent analysis of the stove, and pictures of the biochar, please see the included Report: Results from Preliminary Experiments Conducted on Multi‐level
Primary Air Entry Gasifier Stove