Energie- und Gebäudetechnik
Tel.: 09185 9401-0
Fax. 09185 9401-50
Wood gasifiers are best known from the post-war years when, because of the fuel shortage, we had to be inventive to keep things moving. In the wood gasifier, pyrolysis reactions take place in which, by mixing with air at high temperature, the wood fuel is converted not only into coke or charcoal but also a flammable wood gas that can be extracted, cleaned and put to further use. However, wood gasification suffered from one great disadvantage: the pyrolysis process also produced soot and tar. Older engines could cope with this. Today's high-performance engines, such as are used in modern cogeneration units, cannot accept such by-products.
We have completely rethought and reinterpreted the conventional principle of wood gasification. Hence, our concept differs from the familiar wood gasifiers in the type of process control and in the fuel itself. A technical trick from our experts helped the system become successful:
The process was turned upside down. In this process, the wood pellets are fed into the reactor from below. An updraught cocurrent flow gasification takes place there, while forming a stationary fluidised bed. This is generated with an airflow over a side-channel compressor. A bed material is not necessary here, since the fuel stabilises by itself. Rising means that the stages of gasification (drying, pyrolysis, oxidation and reduction) are passed through from the bottom to the top. The aim is to transfer the highest possible proportion of energy inherent in the solid fuel to the combustible synthesis gas. With our patented process we achieve constant gasification and the resulting optimised, sequential operations with almost complete transfer to the utilisable wood gas. Only the non-decomposable minerals of the biomass remain as ash content.
Substances containing tar are almost completely disintegrated by the uniform reaction conditions and the long dwell time at high temperature ranges, which favours combustion within the engine.
Thus, we are able to achieve a lifespan of over 7500 h/a with consistent performance.