Alongside improving charcoal kiln efficiency and suggesting improved forestry practices CFSP is also developing new high quality charcoal briquettes as an alternative to hardwood charcoal.

Drawing from lessons learned elsewhere in Asia, these initiatives have the potential to significantly ease the pressure on Cambodia’s natural forest by creating charcoal from waste materials.

Studies suggest that well over 20 tons of waste sugar cane bagasse are generated each day from cane juice vendors in the streets and markets of Phnom Penh. Sugar cane waste carbonises well and in October 2003 experiments working towards developing a canecoal briquette were started using the Karve design charring kiln.

The Process
After collection, the sugar cane waste is dried, before it is then converted to charcoal in a charring kiln. Charring produces a good yield of 21% to 23%.
The charred sugar cane waste is ground, mixed with a small quantity of cheap, locally available binder additives, and then extruded into briquettes.

When dry, the briquettes can be packaged and sent to market

Comparing Charcoals
To prove the effectiveness of the charcoal briquettes to potential users CFSP carries out a cooking demonstration. Three typical meals including a stir fry, a soup and rice are cooked simultaneously on a stoves using briquettes, traditional charcoal and charcoal made from prunings from the community forest. Both the briquettes and the community forest charcoal perform well and are comparable to the traditional charcoal

Product Development
For canecoal to be accepted by the market, it needs to be a high quality fuel that is competitively priced and easy to use.
The charring kiln can be either portable or fixed. Using locally available materials the kiln can be constructed for $200 to $300 and has a useful life of x years.
Inside the kiln, the biomass is heated in retorts, metal drums, which give improved temperature control resulting in a better, higher carbon content charcoal. Experimentation has established the best rates of heating and maximum firing temperatures.

The strength of charcoal briquettes during transportation and handling and the quantity of residual dust after burning are also important. All charcoal generates chippings and dust to a certain extent. Dust generated by briquettes must be minimised. Experiments with the combination of additives are underway to achieve the best physical handling characteristics without compromising the calorific value of the charcoal. Bags of briquettes are dropped from a height of 2m, five times, and the quantity of resultant dust pieces < 2cm weighed.

Optimum results are obtained with a 88:3:6:3 mix of char : clay : cassava starch : resin

A 2003 study shows that of the hundreds of tons of waste generated each day in Phnom Penh, 60 tons are biomass that can be considered for use as a basis for charcoal.

Investigations continue to determine the optimum size and location for a sustainable waste to charcoal plant. A promising option is to locate a fixed plant capable of up to 7 tons to production per day at the dump site. The opportunity exists for the municipality’s waste disposal service provider to play a pioneering role in a waste-to-energy project.

At Phnom Penh’s Stung Meanchey landfill site feasibility experiments have been successfully carried out by JICA to produce charcoal and to collect methane.

Biomass charcoal has the additional side benefit of reducing volumes of waste dumped at landfill sites which in turn reduces the levels of methane emitted by the waste site.