Design and Development of a Natural Draft Biomass Gasifier
R. Krishna Kumar February 28, 2009

Naturl Draft Gasifier - KumarNatural Draft Gasifier - Kumar


  • Operates under the principlle of “ Chimney Effectt ”
  • Natural draft caused by density difference


  • No blower is required for the operation
  • Automatically takes the required quantity of air for Gasification
  • Convey the Producer Gas formed by Gasification - Naturally
  • Reduced fuel consumption compared to traditional chulas

More detail, schematic pictures and testing information are in the attached pdfs and in the 2004 discussion:

Rice-powered stove ignites new hope for poor farmers

Alexis BelonioAlexis Belonio

Alexis Belonio, Daniel Belonio, Fraciscus Tria Garleman, Bima Tahar, and Djoewito Atmowidjojo
Minang Jordanindo Approtech, November 2008

Coal Gasifier
Gasifier With Jet Burner

Fuel source for small-scale industry heating application is becoming expensive. This is more so for food, grain, and other processing industries in Indonesia where the energy sources for various processes are highly dependent on conventional fuel. At present, the cost of LPG went up to IDR 7,000 per kg while kerosene and diesel to as high as IDR 12,000 and IDR 5,500 per liter, respectively.

Alexis Belonio, Daniel Belonio, Franciscus Tria Garleman, and Djoewito Atmowidjojo
Minang Jordanindo Approtech, Jakarta Selatan, Indonesia, November 2008

MJA Biomass Gas Stove
Alexis Belonio, July 23, 2008
MJA Biomass Gas StoveMJA Biomass Gas Stove Burning Coal

Alexis Belonio writes (edited and annotated by Paul Anderson and Tom Miles):

Attached is a picture of my latest coal gasifier stove. This
is the same basic TLUD stove I have for wood charcoal and wood chunks.

For domestic use, I use carbonized coal (or coke) as fuel instead
of the raw coal. Coal can be used for the stove, but we don't want to promote
this as a fuel since it emits poisonous gas. I would prefer to use coal for
industry application where gas can be cleaned before it is released to the

I provide only a small amount of coal fuel in the gasifier stove, enough
for cooking. This mean that the power output is only small and the
metal I use is a stainless steel.

I ignite the carbonized coal by using a wood charcoal that has been soaked in
kerosene as igniter. [This is a TLUD stove, so ignition is at the top.]

[In the Belonio TLUDs, the fan only blows the primary air. The
secondary air is
pre-heated as it rises naturally between the fuel cylinder and the outer
cylinder, finally exiting into the rising flow of combustible gases.]
The smoke in the coal gasifier I have was eliminated [combusted] by mixing
preheated air with the gas generated from the reactor. I think
there is no need of [forced] mixing the secondary air by creating turbulence
with the combustible gases. Because in that case, you will need a
slightly bigger fan with enough pressure to push the air.
MJ Biomass Gas StoveMJ Biomass Gas Stove

Alexis Belonio

Top Lit Updraft (TLUD) Gasifier for Carbonized Coal
by Alexis Belonio, Immanuel Ginting, Djoewito Atmowidjojo, and Bony Minang
TLUD for Carbonized CoalTLUD for Carbonized Coal

How to Use a Woodgas or Smoke Burner Stove
N. Sai Bhaskar Reddy, July 1, 2007


Smoke Burner Stove - MAGHSmoke Burner Stove - MAGH

The Woodgas or Smoke Burner Stove technology is new to many users. These are the most efficient Good stoves, with a choice of using different types of available biomass.

Continuous-Flow Rice Husk Gasifier for Small-Scale Thermal Applications
Alexis T. Belonio, Appropriate Technology Center, Central Philippines University, Iloilo City, Philippines, November 11, 2006

Summary of Aprovecho’s Summer Stove Camp, 2006
By Dean Still and Nordica MacCarty, September 6, 2006

Aprovecho Camp 2006 02Aprovecho Camp 2006 02

Stove Camp 2006 was extremely interesting, especially because we had experts here who could help define what is known, figure out what needed to be done to expand the state of knowledge, and then, most importantly, have the tools to accomplish the experiments.

For Dean, the best moments happened around the table above when Chris Roden, Jonathan Lewis, the Aprovecho staff and everyone tried to get a general feeling for wood-burning stoves effect on global warming. Aprovecho’s recent tests at CSU of greenhouse gas emissions such as CO2, Methane, N2O, NOx, etc. helped to predict the gaseous emissions from the following stoves:
• Three stone fire
• Rocket stove
• Karve Gasifier stove
• Philips fan stove
• Charcoal Jiko stove
• Mayon rice hull burning stove

The gases, however, are only a part of the picture: particles also play an important role in the atmosphere. We learned that elemental (black) carbon particles produced in flames have a warming effect 1000 times greater than CO2 per gram, while organic carbon (white) particles produced by smoldering have a cooling effect 150-200 times stronger than CO2. Thankfully, Chris Roden had brought his and Dr. Tami Bond’s ARACHNE system which could measure the composition of the total PM to determine what percentage of black or white particles were produced by the stoves above. Chris, Damon and Nordica were at the lab till 11pm having a great time testing these stoves. Results should be available soon.

Doing this kind of research in a small lab in Creswell, Oregon for no money is what ETHOS stove camp is all about!

The publicized theme of this year’s camp was a competition to design the cleanest-burning fan stove. Two categories, side feed and top feed were awarded prizes. The top feed prize went to Dr. Paul van der Sluis for the Philips fan stove. The side feed Rocket stove with fan developed by Roger and Sule of Colorado State was the cleanest burning side feed stove. Congratulations to the winners!


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