Methods of grinding materials. The methods may include introducing a material and a circulating fluid to a jet mill and recycling the circulating fluid. The material may include coal. Systems of grinding materials also are provided.

An emulsion system is provided. The system includes a shaft that supports a plurality of cutting assemblies and screens in alternating order, wherein the cutting assembly rotates with respect to an in close proximity to the screen. The cutting assemblies include a plurality of cutting elements that extend radially outward from a hub and are positioned at consistent radial spacing along the perimeter of the hub. Each cutting element includes front and back edges that cut food particles in conjunction with holes within the screen, wherein the front and back edges are substantially perpendicular.

An emulsion system is provided. The system includes a shaft that supports a plurality of cutting assemblies and screens in alternating order, wherein the cutting assembly rotates with respect to an in close proximity to the screen. The cutting assemblies include a plurality of cutting elements that extend radially outward from a hub and are positioned at consistent radial spacing along the perimeter of the hub. Each cutting element includes front and back edges that cut food particles in conjunction with holes within the screen, wherein the front and back edges are substantially perpendicular.

An emulsion system is provided. The system includes a shaft that supports a plurality of cutting assemblies and screens in alternating order, wherein the cutting assembly rotates with respect to an in close proximity to the screen. The cutting assemblies include a plurality of cutting elements that extend radially outward from a hub and are positioned at consistent radial spacing along the perimeter of the hub. Each cutting element includes front and back edges that cut food particles in conjunction with holes within the screen, wherein the front and back edges are substantially perpendicular.

An emulsion system is provided. The system includes a shaft that supports a plurality of cutting assemblies and screens in alternating order, wherein the cutting assembly rotates with respect to an in close proximity to the screen. The cutting assemblies include a plurality of cutting elements that extend radially outward from a hub and are positioned at consistent radial spacing along the perimeter of the hub. Each cutting element includes front and back edges that cut food particles in conjunction with holes within the screen, wherein the front and back edges are substantially perpendicular.

A system and method for freezing and breaking down tires or other materials is disclosed. The system and method for freezing and breaking down tires includes using a shredder to shred the tires, using a filter to screen the tire shreds, using a water sprayer to rinse the tire shreds, using a freezing tunnel to freeze the tire shreds before they are crushed into tire grains, using a magnet to remove any metallic fibers, filtering out any oversized tire grains for re-freezing and re-crushing, and using a separator to separate out any oversized or undersized pieces before bagging the final tire grains for re-use and recycling.

Coconut crumb can serve as an infill material on synthetic turf fields in the place of tire crumb. The crumbs are less than 10 mm big and have smooth corners and edges. The process of producing the coconut crumb involves successive grinding or milling processes that reduce the inner hard shell of the coconut to particles of an appropriate size for infill, while screening out the unwanted material from being included in the infill.

Disclosed herein are systems and methods for processing waste egg shells into (i) a first product comprising calcified egg shell particles having diameters of 3μ or less, and (ii) a second product comprising calcified egg shell particles having diameters in a range from about 3μ to about 7μ. The first product may be used as a CaCO.sub.3 substitute for paint compositions and plastics compositions. The second product may be used as a CaCO.sub.3 blasting media substitute for use with abrasive blasting equipment.

Disclosed herein are systems and methods for processing waste egg shells into (i) a first product comprising calcified egg shell particles having diameters of 3μ or less, and (ii) a second product comprising calcified egg shell particles having diameters in a range from about 3μ to about 7μ. The first product may be used as a CaCO.sub.3 substitute for paint compositions and plastics compositions. The second product may be used as a CaCO.sub.3 blasting media substitute for use with abrasive blasting equipment.

A method of processing magnetite iron ore, including the step of using a high pressure grinding roller (HPGR) to crush the magnetite. An apparatus for processing magnetite iron ore, including a first high pressure grinding roller for crushing the magnetite, a dry screen for selectively feeding back material to the first high pressure grinding roller, an air classifier for selectively feeding back material to the second high pressure grinding roller, a second high pressure grinding roller for grinding the magnetite, and a dry magnetic separation (DMS) unit for discarding non-magnetic materials, wherein the dry magnetic separation unit is outside the two feedback loops associated with the first and second high pressure grinding rollers.