Size Enlargement EquipmentBy: ANGELES, Katrina ZARRAGA, Christina
Size Enlargement
Process where small particles are brought together to form lumps of a desired size
Original particles can still be distinguished
To improve handling properties
To reduce caking and lump formation
To improve flow properties
To increase bulk density for storage and tableting feeds
To control solubility, porosity, surface-to-volume ratio
Size Enlargement
GRANULATIONSize Enlargement
Tumbling Granulators
Particles are set in motion by the tumbling action caused by gravity and centrifugal forces
Continuous feed
Generally produce 1-20 mm granules, not suitable for making granules less than 250μm
Can run at large scale
Disc granulators, drum granulators
Disc Granulatoro also: pelletizer (iron ore industry), pan granulator agricultural chemical industry)
o Made of a rotating tilted disc or pan with a rim
Disc Granulator
Disc Granulator
Disc Granulator
Size classification/segregation:Small granules, ungranulated feed are thrown high on the disc by centripetal forces
Large granules remain in the eye and exit as product
Drum Granulator
Used for large-scale productions
Common in metallurgical, fertilizer industries
No output size classification high recycle rates of off-size product
Drum Granulator
Drum Granulator
Drum Granulator
Tumbling Granulators
Mixer Granulators
Low-Speed Mixers
Low-Speed Mixers
Low-Speed Mixers
Low-Speed Mixers
Continuous Shaft Mixers
Consist of blades/pins rotating at high speed on a central shaft
Operate at high speeds of 200-3500 rpm
Produces granules of 0.5-1.5 mm
Granulated product is generally fine, irregular, with low bulk density
Applications: detergents, agricultural chemicals, clays, ceramics, foodstuffs, carbon black
Continuous Shaft Mixers
Batch High-Speed Mixers
Plow-shaped mixers rotate on a horizontal shaft at 60-800 rpm
Most have an off-center high-speed cutter/chopper rotating at 500-3500 rpm breaks down overwetting powder mass and limits the maximum granule size
Granulation times range from 5-10 min
Batch High-Speed Mixers
Lodige horizontal plough shear design
Gral designs
Batch High-Speed Mixers
Fielder designs Diosna designs
Batch High-Speed Mixers
Eirich mixer granulator
Both chopper and impeller blades rotate on eccentrically mounted vertical shafts, cylindrical bowl also rotates
Hybrid of mixer and tumbling granulation
More spherical granules are produced than those in other batch mixer processes
Batch High-Speed Mixers
Fluidized Bed Granulator
Particles are set in motion by air rather than mechanical agitation
Produces high-porosity granules and high-strength, layered granules
Fluidized Bed Granulator
Batch Fluid-Bed Granulator
Batch Fluid-Bed Granulator
Continuous Fluid-Bed Granulator
Spouted-Bed Granulator
Spouted-Bed Granulator
Centrifugal Granulators
Centrifugal Granulators
Centrifugal Granulators
COMPACTION Size Enlargement
Piston & Molding Press
Used to create uniform and intricate compacts
Consists of a mechanical/hydraulic press
Due to pressure and heat, the particulate charge causes it to flow and take the shape of the mold
Tableting Press
Used for applications with strict specifications for weight, thickness, hardness, density, appearance of agglomerate
Produces simpler shapes at higher production rates than molding presses
Roll Press
Compresses raw material as it is carried into the gap between two rolls rotating at equal speeds
Size and shape of agglomerates are determined by the geometry of the roll surfaces
Can produce large quantities of materials at low cost
Product is less uniform
Pellet Mills
Moist plastic feed is pushed through the holes in dies of various shapes
Friction of material in the die holes provides the resistance needed for compaction
Adjustable knives shear the product into pellets of desired length
Screw and Other Paste Extruders
Uses a screw to force material in a plastic state continuously through a die
Shape of the die hole determines the shape of the compact
Round hole: rod-shaped
Thin slit: film/sheet
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