Production of high quality hemp shives with a new cleaning system
Leibniz Institute for Agricultural Engineering Potsdam-Bornim (ATB), Max- Eyth-Allee 100, 14469 Potsdam, Germany; *Correspondence: firstname.lastname@example.org
A shortage as well as a rise in costs for raw materials as used for production of derived timber products and fibre composites can be observed for quite some time. Especially the use of wood as energy source has led to an increased demand for cellulose raw materials. Non wood resources e.g. from agricultural production are coming into consideration as alternatives or as replenishment to conventional raw material stock. Therefore, there is an increasing demand for high-grade hemp and flax fibres as a raw material e.g. for production of natural fibre reinforced composites. Within this context also the non-fibrous fraction of fibre plants – shives or hurds – are suitable for different applications in composite or fibre board industry. At present, approx. 50% of the income of a hemp fibre processor is generated by marketing quality shives. There is still a substantial need for efficient shive processing and cleaning technologies. Cleaned high quality hemp shives can be used not only for animal bedding, but also for particle board or composite production. Hence, ATB has developed a simple but efficient technology for cleaning of shive-fibre mixtures. It allows classification and cleaning of shives as well as recovering of short fibres in only one processing step. On basis of these results, the developed fractionating system has been patented and scaled up to an industrial system in cooperation with a machine supplier for hemp processing equipment. The machine has been successfully tested with different machine settings as well as different varieties of input material.