The EcoKiln technology – Producing burnt clay bricks in an energy efficient manner
Soumen Maity1, Peter Schramm2
1Development Alternatives, New Delhi, India; 2Centre for International Migration and Development, Eschborn, Germany
The developing and under-developed countries in Asia and Africa have been showing un-precedent growth in human development. This has resulted in better jobs and increased incomes with more disposable money to invest. The most important investment preferred has been the housing sector ensuring social security. In most areas of Africa and Asia burnt clay bricks are still the preferred walling materials for housing despite the advent of alternate materials. The choice of alternatives are limited by affordability. Thus burnt clay bricks will continue to be the preferred choice for housing in decades to come.
Across both the continents burnt clay bricks are produced by age old technologies e.g. various forms of clamps and Bulls Trench Kilns. In some countries the choice of tunnel kilns has been widespread but limited. The clamps in Africa mostly uses fuelwood as a primary fuel with limited knowledge or practice of other fuel types. In Asia coal and waste biomass is being used as a primary fuel for clamps and other firing technologies.
The present paper discusses the development and dissemination of a new kind of burnt clay brick firing process i.e. the EcoKiln technology. This is based on the principles of vertical shaft brick kiln technology and uses only coal as the fuel for burning. A counter-current heat exchange system in the technology alongwith use of refractory lining ensures arrest of heat loss thus saving energy. Further heat loss is also reduced by the addition of internal fuel within the green bricks.
It has been found in Asia and Africa that the EcoKiln technology saves around 40-50% of energy compared to open clamps having a specific energy consumption of 0.50-0.80 MJ/kg. This has made the EcoKiln technology the world’s most energy efficient system of burnt clay brick production.