Several trends can be identified in the pellet industry: On the one hand, the design and erection of ever larger plants with a production capacity of up to 2 million tons of pellets. On the other hand, plants that process not only wood, but a wide variety of biomass. As a result of the worldwide energy and raw material awareness, the focus is increasingly on natural resources, which have so far attracted little attention. And the trend continues: Especially the demand for plants for the production of pellets from stalk-like biomass such as straw is unbroken.
For these two trends AMANDUS KAHL designs turnkey plants with its own machines – manufactured in Reinbek – such as belt driers, crushing units, conditioners, pellet mills, coolers including switch cabinet construction and programming of the control and regulation of these plants.
The challenge of such turnkey plants is not the pelleting of the straw, but the conditioning of the straw prior to pelleting. Straw and straw bales can have extremely different properties - from the length of the chopped straw to the shape of the straw bales. The ideal solution is a robust technology that reliably disintegrates all types of straw bales and thus makes further processing of the straw bales possible in the first place. For this reason, AMANDUS KAHL develops machines that adapt precisely to these different requirements.
Process sequence
For processing such hardly specified biomass, wet pelleting can be used, i.e. the mixture of various, only crushed biomass is pelleted in moist condition before being dried. During drying, the pellets harden to a certain extent. However, this step depends largely on the moisture content of the input product, which is in the ideal range at 14 to 16 percent. Some plants are therefore equipped with a fabric belt drier. Other plants, on the other hand, have a good straw bale management and appropriate storage facilities, so that only dry straw bales are available. Afterwards, the material is further crushed in our KAHL hammer mill, then conditioned with steam and water and finally pelleted. The resulting pellets are cooled and any fines separated by screening. Finally, the pellets are intermediately stored in silos until they leave the plant.
Applications and Advantages
- Thermal utilization
- High bulk density
- Practically dust-free
- Easy to store
- Easy to transport
