Evaluation of reed canary grass shredding and compacting properties
Latvia University of Agriculture, Faculty of Engineering, Institute of
Mechanics, J. Cakstes bulv. 5, LV-3001 Jelgava, Latvia;
*Correspondence: andris.kronbergs@llu.lv
Abstract:
Reed canary grass biomass is recommended for solid biofuel production. The main conditioning operation before preparation of herbaceous biomass compositions for solid biofuel production is shredding. Shredding can increase bulk density up to 165 kg m-3. Biomass compacting represents technology for the conversion of biomass into a solid biomass fuel in the shape of briquettes and pellets. Compacting of biomass is one of the important processes for effective handling, transport and storage of this biomass fuel material. The purpose of the work was to investigate reed canary grass (Phalaris arundinacea) comminuting energy, bulk density and briquetting energy dependence on hammer mill screen opening sizes. For comminuting was used a hammer mill, equipped with four different screens with opening sizes 20, 12, 6 and 1.5 mm. Comminuting energy for these opening sizes was stated within 11–236 kJ kg-1 . Bulk density for reed canary grass by comminuting can be increased up to 165 kg m-3 if hammer mill screen with opening size 1.5 mm is used. For briquetting experiments were used a hydraulic laboratory press, where for compacting were used five different pressure levels – 90, 120, 150, 180 and 210 MPa. Maximum density 899–964 kg m-3 had been achieved for compacting pressure 210 MPa. Summary energy consumption for comminuting and briquetting is approximately 50 kJ kg-1 if screen opening sizes are 12 and 20 mm in comminuting. For these sizes briquette density is 899 and 915 kg m-3 .
Key words:
briquetting, comminuting, herbaceous biomass