This presentation was put together by A.Phrao, Chiang Mai of the Warm Heart Foundation in Thailand. They are using biochar to attempt to restore fertility to badly degraded mountain soils, and to intensely fertilized mono-cropped soils that have low fertility.

They designed this medium sized TLUD system with the following constraints:
They wanted to design a simple, low-cost biochar burner that:

  • Can be built from locally available materials, preferably recyclables, at little cost;
  • Can be manufactured by local mechanics without
  • training;
  • Can be operated safely and efficiently by a single person;
  • Can use a variety of feed stocks, preferably field waste;
  • Can produce a minimum of 1 ton of biochar per week under normal, unpressured operating conditions.

The solution is pretty ingenious - please take a look at the PDF for all of the details.

The following is quoted from the pdf:
The 6-burner TLUD merry-go-round:
materials list

  • • 1 x children’s playground merry-go-round or equivalent
  • • 6 x 200 litre steel drums
  • • 6 x 60 litre steel drums
  • • 8 x meters 1” OD steel pipe
  • • 6 x meters 1” angle iron
  • • 6 x 3” hinges
  • • Miscellaneous nuts and bolts, welding rods, grinding wheels
  • • Circular grinder, arc welder


  • • 6 TLUD burners
  • • 55 kg corn cob load/barrel
  • • 20+ kg biochar output/barrel
  • • 120 kg per burn
  • • Single man can load, light, rotate, load, light, rotate…empty, extinguish, empty, extinguish… all six loads in 1.5 hrs.
  • • Single man can grind full load in 1.5 hrs.
  • • Two full loads per day = 240 kg/day
  • • 6 day week = 1,440 kg/wk
  • • Feed stock requirement = 3,600 kg/wk
  • • Cost: corn cob @ 700 baht/ton ($23.35) or $60/ton biochar if farmer does not have own supply

New video and print resources available at

Contamination of drinking water sources by synthetic organic compounds (SOCs – e.g. pesticides, pharmaceuticals, fuel compounds, etc.) is a growing worldwide problem. Many of these chemicals bio-accumulate in the human body and cause cancer, birth defects and diseases of the reproductive system, and disrupt endocrine and neurological systems. However, few low-cost, sustainable and appropriate treatment technologies are available to rural and developing communities for SOC removal.

Water filtration using charcoal is an ancient practice that continues today in non-industrialized regions around the world, though it has not yet been rigorously demonstrated for removal of modern industrial pollutants. Unfortunately, charcoal production by traditional kiln systems is often a resource-intensive and highly polluting process, and kiln processes are typically not optimized for production of good water filter char. Low cost, energy efficient, environmentally sustainable and scalable local production of optimal water filter char can be accomplished with biomass gasification (e.g. cookstoves and larger units using the TLUD design).

The video and print resources available on the Aqueous Solutions website ( are intended to

  1. summarize current results of collaborative field and laboratory research pertaining to the use of traditional kiln charcoals and gasifier chars in decentralized water treatment that targets SOCs,
  2. provide instructional materials for construction and operation of small- and intermediate- scale gasifier char production units using local materials, and
  3. provide instructional materials for integration of biochar filtration into a multi-barrier small- and intermediate- scale water treatment systems constructed from inexpensive and widely available materials.

Quoting "Prof. S.C. Bhattacharya" :

Dear all,

I would be happy to share some publications arising from the following
activities at the Asian Institute of Technology:
1. Sida funded Regional project: An information package (including
construction details) on biomass briquetting machines developed in a
number of Asian countries and design of natural- cross-draft gasifier stoves that can operate continuously is available. The briquetting machines developed
were improvements on standard screw-press heated die design. Cross-flow
gasifier stoves were designed for different sizes; these do not need any
blower and can operate continuously without any smoke.

The briquetting and gasifier stove work I mentioned was carried out under a
Sida-sponsored project at the Asian Institute of Technology (AIT). The
project involved researchers from 12 national research institutes of six
Asian countries, e.g., Bangladesh, Cambodia, Lao PDR, Nepal, Philippines and
Vietnam. The findings of the project were disseminated through national
dissemination seminars in these countries; published "Technology packages"
were distributed widely in the region and are still available for
downloading from the project website. We organized technology transfer
workshops, in which a number of NGOs form the region were invited, on most
of the technologies developed.

(There is no restriction on distribution of the technology packages.)

Unfortunately, the link of the project is not working due to heavy flood in
Thailand; AIT appears to be still under 2 m of water.

2. GTZ funded project on Biocoal: We used the term "Biocoal" (rather than
"Biochar") for charcoal produced from solid organic residues such as
agricultural residues and waste wood. The findings of the project were
reported in a book titled "Biocoal Technology and Economics" by "Regional
Energy Resources Information Center (RERIC)" (

The chapters of the 495-page book were:

  • 1. State of the art of biocoal technology,
  • 2. Biocoal technology: A comparison of options and recommendations,
  • 3. Carbonisation of sawdust briquettes,
  • 4. Laboratory-scale batch carbonisation selected residues,
  • 5. Cost and availability of selected residues in Thailand,
  • 6. Characterisation of selected residues,
  • 7.Biocoal: Market requirements and Opportunities in Thailand, and 8. Economics of biocoal production in Thailand.

A few copies of the book are still available with RERIC. A number of
chapters of the book were summarised as journal articles; I will be happy
share some of these with interested persons for their personal use and
research purpose.

Other technology packages and published papers of the Sida project can be downloaded from The biomass/stove group may be interested the package on drying, which includes a hybrid drier using solar energy and bioenergy from a gasifier stove, heat output of which could be automatically controlled by using a thermostat.

I also coordinated another regional project (Asian Regional Research Programme in Energy, Environment and Climate, ARRPEEC) funded by Sida in three phases during 1995-2005. One of the 4 projects of ARRPEEC was on biomass. Dissemination booklets of ARRPEEC and some of the papers published can be downloaded from

....The stove is a modification of the Avan + Inverted Downdraft to reduce the height of it so that small food/noodle shop in rural area may be interested in trying it......- Monk Viravat Charoenbenchavong

Recent Posts to the Fuel Briquetting Discussion
Megan Hill, Richard Stanley, Kari Grady Grossman, Robert Deutsch, David Sawwah, September 4, 2007
David Sawwah, Northwest ThailandDavid Sawwah, Northwest Thailand

Appropriate Technology Association

135/4 Moo4, Thanarat Rd
Tambon Moosi, Pak Chong District
TH-30130 Nakorn Ratchasima
Tel: +66 1 9155438 Fax: +66 44 297621

Wim Hulscher, Zheng Luo, Auke Koopmans
FAO-RWEDP, Bangkok HEDON December 1999

It is explored how programmes for introducing (improved) woodstoves can bejustified in terms of greenhouse gas reduction at competitive cost. The discussion is put in the context of real life observations in Asia and alternative justifications for stove programmes. A few options for putting stoves on the international 'carbon market' are briefly analysed. Tentative results show that a stove project could well result in reduction of CO2 emission at a cost of less than 2 US$/ton.

Making Charcoal From Chopstick Bamboo, Lampang, Thailand
Matthew Owen August 2002
Chardust Kenya Kenya

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