Compression milling

Gyratory crushers 2. Rolling-compression mills with internal cutters ... 

Although compression mills may differ from one another in whether one or both surfaces are moving, no compression mill subclasses have been identified. 

Compression Mills None Identified MCA International Ross Stokes-Merrill... 

Compression Milling Particle size reduction by compression stress and shear between two surfaces... 

Pulverization can reduce the size as well as the crystallinity of cellulosic materials and increase the surface area and bulk density. It is also possible to separate part of the hgnin from carbohydrates which makes it easier for microorganisms to digest cellulose. Various equipment, such as a compression mill, a bead mill, an extruder, a roll mill and disc refiners, etc., can be used for pulverization. Unfortunately these methods tend to be very expensive and too energy intensive. For sohd-state fermentation, if the particles are too fine, the oxygen mass transfer will become a big problem therefore, hghtly crushed or just ground raw material will suffice. 

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