Reliance on charcoal as a solid fuel wreaks havoc with forests and adds to pollution levels. Now new technology has been developed in Zambia to cut charcoal consumption by one-third. And, reports Gemini News Service, several other countries want to buy the equipment. Wachira Kigotho writes from Nairobi, Kenya

Researchers in Zambia have developed new technology that might eventually cut charcoals consumption to 30 per cent of fuel needs.

It involves efficient clay cookstoves and coal briquettes, as an alternative smokeless solid fuel.

By encouraging people to use the briquettes. Zambia hopes to reduce the heavy deforestation blighting the country's land and its biodiversity. At present. Zambia obtains 90 per cent of its household fuel from charcoal and firewood, although it has large deposits of untapped coal.

The technology was developed by Industrial Minerals, and Energy Research, a laboratory of the National Council for Scientific Research (NCSR).

"By promoting coal and other biomass-based briquette technology. NCSR has taken a step towards sensitising other countries in sub-Saharan Africa to the need to protect fragile ecosystems." says Mitsuo Ishikawa, resident representative in Zambia for Japan International Co-operation Agency (JICA). which collaborated on the proiect.

Coal briquettes burn with a blue flame, are smokeless and emit no soot. They are also more dense and more porous than charcoal, and break less easily during handling and

transportation. They can be quenched with water, and lit again once dry.

As well as developing the briquettes, researchers have designed a new clay stove that should help revolutionise household fuel consumption.

The stove keeps fire much longer than the traditional mbaula metal one. says Dr Julius Banda, an expert in ceramics who helped develop the stove with officials from JICA.

An aggressive campaign has taken ofTin Zambia to train local artisans in making the clay stoves by hand. Some artisans are trained at an NCSR plant while instructors visit other locations. such as Chipata and George Compound, to train workers on the ground.

And while the clay stove is more economical than other ordinary types of cookstove when using charcoal, it is even more efficient with coal briquettes.

NCSR and JICA’s ceramics experts believe that the useful heating period is up to three hours with charcoal, but between six and eight hours with the briquettes.

The old mbaula stoves, similar to those commonly used in Tanzania. Uganda and Kenya, retain heat only for 30-45 minutes.

Zambia is on the way to marketing the briquette tech-

nology. as well as establishing a regional centre for training and testing the technology. It remains. according to Dr Kaoma. the only sub-Saharan country capable of commercialising it.

According to Dr Julius Kaoma, principal researcher on the project, the raw materials used to make coal briquettes are all available in Zambia. They include coal waste slurry, agricultural wastes such as bagasse and maize cobs, molasses. sawdust and lime.

The process consists of removing tarry and gritty substances from coal slurry and agro-waste through a carbonisation process. The products are then crushed and ground into Eowder. and mixed with water.

I me is added to remove sulphur, and molasses to bind it.

The mixture is then moulded into briquettes, passed through low pressure, and desmoked by curing. "We have the capacity to make coal briquettes of any shape, size or quality.” says Kaoma.

Zambia Suga Company shows it is also possible to make smokeless briquettes from bagasse, a by-product of sugar processing. Bagasse is usually discarded, posing an environmental hazard to the area in which it is dumped.

To attain its goal of conserving Zambia's forests. NCSR

would like to make the briquette project.an income generator. Funds are needed to upgrade the mini-laboratory to a semi-commercial plant, capable of producing 10.000 tonnes of briquettes a year.

A request from one company in Johannesburg to supply 5.000 clay stoves has gone unfulfilled because the NCSR lacked the capacity. Last year the 8.000 stoves produced were all sold locally.

In the last two years, NCSR has also had requests from governments and private companies in neighbouring countries to help with coal briquette technology and with testing their co^l

Botswana and Malawi are both interested. Tanzania's Industrial Research Development Organisation sees it as a way to cut charcoal burning in the south of the country.

And in Zimbabwe the University's Institute of Mining Research has shown interest and visited the NCSR's lab, and the Universal Merchant Bank may finance coal briquette entrepreneurs across Central Africa.

— Gemini News

The writer Is the Education Editor of the East African Standard In Nairobi.