Development of an Axial Fractionator for Hemp Shive Cleaning and Industrial Applications of Shives

Due to increasing shortage of raw materials, traditionally used for production of wood based panels and other composite materials, there is a growing call for the use of raw materials from agricultural production. Hemp shive, a by-product of hemp straw processing, is in eager demand due to its wood-like material properties. In order to be suitable for industrial use, respective agricultural raw material must be competitive in price, as well as be available in respective quantity and quality. ATB has developed a new processing technology for the cleaning of shive-fibre mixes for better accommodation such requirements. Ultimate goal is the generation of dust and fibre free shives as well as the recovering of high quality short fibres from shive fractionation. This is facilitated by a new type of axial fractionators, which utilizes a multi-stage paddle screw and a screen drum, corresponding with the screw. This allows classification and cleaning of the shives as well as recovering of the short fibres in only one processing step. Finished products are widely dust and fibre-free, high value shives; and shive-free short fibres. The shives can be used for the production of particle boards without further preparation. The recovered short fibres are mainly suitable for the use as reinforcing fibres in composite materials due to their short fibre length (<50 mm). In cooperation with a machine engineering company, the design of the developed axial fractionator shall be adapted for industrial application. Owed to its simple and flexible design, common by-products of hemp processing can be processed at reasonable costs into high-quality market-going products.Â