This project deals with the transformation of biomass to building materials and energy (eco-materials, economic and ecologic building materials). Building materials and energy have always been directly related to each other. The production of most building materials depends on a process which in general uses a large amount of energy to burn materials at high temperatures or to grind coarse components into fine ones.

Steel and binding agents are among the building materials of which the production requires most energy. To produce a binding agent, the individual components must be heated up to more than 700°C, in some cases even to above 1000°C.

The production of binding agents causes emission of large quantities of the greenhouse gas CO2 which is well known to negatively impact the environment. There also are other building materials which though their production uses less energy, have negative effects on the environment all the same because their production results in a reduction of renewable resources, like for example deforestation of tropical forests. Usage of wood as fuel for the production of lime or for the burning of clay bricks are examples for the situation in developing countries where conventional fuels are not available. A disconcerting problem in developing countries is the way in which the huge quantities of waste are handled that are created by industry and agriculture. A significant part of the waste is biomass which could be used as a renewable fuel, for example in the building materials industry. Due to the prevalent infrastructure in most developing countries, there is currently no possibility to organize initiatives to recycle combustible waste in a sensible manner.

The project promotes recycling of unused biomass. This comprises agricultural waste, waste paper and the organic fraction of solid urban wastes (SUW).

Semi-industrial agricultural wastes as well as remains from the rice and coffee harvest are the potential main sources of non-decomposing biomasses. Solid urban wastes are another important source of biomass which moreover become with increasing frequency a big problem for large cities, even in medium sized towns. The usage of clay is proposed as binding agent for such biomasses. In addition to the binding capacity of he particles contained in clay, the clay minerals can be activated by changes of their inner structure at temperatures of 800-1000°C, depending on the type of clay. The result of this process is a reactive pozzolan-cement. The idea of a solid fuel block (SFB) takes both binding properties of clays into account. Before burning, the clay acts as binding agent keeping the biomasses together; then, during burning of the solid fuel block, the available portion of clay is activated by the increase of temperature and thus becomes reactive pozzolan-cement which can be used for the production of lime-pozzolan-cement.

This product represents an interesting, environmetally friendly and cost saving variant of renewable building materials which achieves significantly improved efficiency compared to conventional building materials. Wastes that cannot be properly disposed of otherwise, can by its usage be recycled at small scale.

This technology was developed by our international partners CIDEM (Centro de Investigación y Desarrollo de Estructuras y Materiales) in Santa Clara in Cuba, Grupo Sofonias in Swizzerland and the EcoSur network of Nicaragua. It can be deployed on any building site, in large as well as in small undertakings, especially in third world countries.