Difference between revisions of "Sizing"

There are two types of grinding: coarse grinding, which can then be followed by fine grinding. Normally a grinder is used to crack bigger parts into smaller particles. The size of the resulting materials is typically 0.2–2 mm. Grinding is achieved by shearing and/or friction and the effect is achieved by multiple comminution in an increasingly narrowing grinding gap, which can usually be varied by axial displacement of a rotor or stator. The frequently tested process variables are screen size, angular velocity, time, feed rate, type, feed size, load, moisture content, and process.<ref>{{Cite journal|author=Tumuluru JS, Heikkila DJ|year=2019|title=Biomass Grinding Process Optimization Using Response Surface Methodology and a Hybrid Genetic Algorithm|journal=Bioengineering|volume=12|issue=6, no. 1|page=1-12|doi=10.3390/bioengineering6010012}}</ref>  

There are two types of grinding: coarse grinding, which can then be followed by fine grinding. Normally a grinder is used to crack bigger parts into smaller particles. The size of the resulting materials is typically 0.2–2 mm. Grinding is achieved by shearing and/or friction and the effect is achieved by multiple comminution in an increasingly narrowing grinding gap, which can usually be varied by axial displacement of a rotor or stator. The frequently tested process variables are screen size, angular velocity, time, feed rate, type, feed size, load, moisture content, and process.<ref>{{Cite journal|author=Tumuluru JS, Heikkila DJ|year=2019|title=Biomass Grinding Process Optimization Using Response Surface Methodology and a Hybrid Genetic Algorithm|journal=Bioengineering|volume=12|issue=6, no. 1|page=1-12|doi=10.3390/bioengineering6010012}}</ref>  

=== Milling ===

=== Milling ===

Milling combines several mechanical stresses, such as compression, friction, impact, and shear. The combination of these stresses reduce the particle size, crystallinity, and degree of polymerisation, making the biowaste more accessible for further processing. However, milling is energy intensive and has a high capital cost. The required energy can be reduced by combining milling with other processes.<ref>{{Cite journal|title=Ball milling as an important pretreatment technique in lignocellulose biorefineries: a review|year=2021-08-12|author=Yalew Woldeamanuel Sitotaw, Nigus G. Habtu, Abaynesh Yihdego Gebreyohannes, Suzana P. Nunes, Tom Van Gerven|journal=Biomass Conversion and Biorefinery|doi=10.1007/s13399-021-01800-7}}</ref>

Milling combines several mechanical stresses, such as compression, friction, impact, and shear. The combination of these stresses reduce the particle size, crystallinity, and degree of polymerisation, making the biowaste more accessible for further processing. However, milling is energy intensive and has a high capital cost. The required energy can be reduced by combining milling with other processes.<ref>{{Cite journal|title=Ball milling as an important pretreatment technique in lignocellulose biorefineries: a review|year=2021-08-12|author=Yalew Woldeamanuel Sitotaw, Nigus G. Habtu, Abaynesh Yihdego Gebreyohannes, Suzana P. Nunes, Tom Van Gerven|journal=Biomass Conversion and Biorefinery|doi=10.1007/s13399-021-01800-7}}</ref>