Animal bedding is disclosed. The animal bedding comprises a juniper tree cut at ground level, the juniper tree having needles and a trunk. The juniper tree is naturally dried until the needles are brown, then ground using a screen that is 3 inches or less. The ground juniper tree is hammer milled and dust of 20 mesh minus is extracted from the hammer milled tree, which is then placed in a bagging machine and dust is vacuumed from the juniper tree. The juniper tree is then bagged.

A method for manufacturing polycrystalline silicon fragments includes producing a polycrystalline silicon rod by the Siemens method; crushing the polycrystalline silicon rod to obtain polycrystalline silicon fragments; and cleaning by etching the polycrystalline silicon fragments in a cleaning tank. In the cleaning, small pieces of the polycrystalline silicon having controlled shapes and sizes are present in the cleaning tank and the weight change of the small pieces of the polycrystalline silicon before and after the etching is measured to thereby manage the cleaning.

A multistage hammer mill 10 has a plurality of milling stages arranged concentrically so that substantially all material in a first innermost of the milling stages passes through all subsequent adjacent milling stages. A central feed opening 12 enables material flow into a primary impact zone 14 of a first milling stage, which has an impact mechanism 16 and a first screen arrangement 20a. The impact mechanism 16 rotates about a rotation axis 18. The first screen arrangement 20a is disposed circumferentially about and radially spaced from the impact mechanism 16 and has a plurality of apertures 22 through which impacted material of a first size range can pass. A second milling stage has a second arrangement 20b disposed circumferentially about and radially spaced from the first screen arrangement 20a and a circular array of impact elements 50a between the first and second screen arrangements.

A multistage hammer mill 10 has a plurality of milling stages arranged concentrically so that substantially all material in a first innermost of the milling stages passes through all subsequent adjacent milling stages. A central feed opening 12 enables material flow into a primary impact zone 14 of a first milling stage, which has an impact mechanism 16 and a first screen arrangement 20a. The impact mechanism 16 rotates about a rotation axis 18. The first screen arrangement 20a is disposed circumferentially about and radially spaced from the impact mechanism 16 and has a plurality of apertures 22 through which impacted material of a first size range can pass. A second milling stage has a second arrangement 20b disposed circumferentially about and radially spaced from the first screen arrangement 20a and a circular array of impact elements 50a between the first and second screen arrangements.

A multistage hammer mill (10) has a plurality of milling stages arranged concentrically about each other. The plurality of milling stages arranged so that substantially all material in a first inner most of the milling stages passes through all subsequent adjacent milling stages. The milling stages include a first milling stage and a second milling stage. A central feed opening (12) enables material flow into a primary impact zone (14) of the first milling stage. The first milling stage has an impact mechanism (16) and a first screen arrangement (20a). The impact mechanism (16) rotates about a rotation axis (18). The first screen arrangement (20a) is disposed circumferentially about and radially spaced from the impact mechanism (16) and is provided with a plurality of apertures (22) through which impacted material of a first size range can pass. The second milling stage has a second arrangement (20b) disposed circumferentially about and radially spaced from the first screen arrangement (20a) and a circular array of impact elements (50a) disposed between the first screen arrangement (20a) and the second screen arrangement (20b).

A multistage hammer mill (10) has a plurality of milling stages arranged concentrically about each other. The plurality of milling stages arranged so that substantially all material in a first inner most of the milling stages passes through all subsequent adjacent milling stages. The milling stages include a first milling stage and a second milling stage. A central feed opening (12) enables material flow into a primary impact zone (14) of the first milling stage. The first milling stage has an impact mechanism (16) and a first screen arrangement (20a). The impact mechanism (16) rotates about a rotation axis (18). The first screen arrangement (20a) is disposed circumferentially about and radially spaced from the impact mechanism (16) and is provided with a plurality of apertures (22) through which impacted material of a first size range can pass. The second milling stage has a second arrangement (20b) disposed circumferentially about and radially spaced from the first screen arrangement (20a) and a circular array of impact elements (50a) disposed between the first screen arrangement (20a) and the second screen arrangement (20b).

The various embodiments disclosed and pictured illustrate a hammer for comminuting various materials. The embodiments pictured and described herein are primarily for use with a rotatable hammermill assembly. The hammer includes a connector end having a rod hole therein, a contact end for delivery of energy to the material to be comminuted, and a neck affixing the connector end to the contact end. The neck is formed with at least one neck recess therein. In other embodiments, one or more shoulders are positioned around the periphery of the rod hole for added strength. In still other embodiments, the contact end is configured with more than one contact surface.

A method for producing animal bedding is provided. A juniper tree is cut at ground level, the juniper tree having needles and a trunk. The tree is naturally dried until the needles are brown, then ground using a screen less than 3 inches. The ground juniper is hammer milled and dust of 20 mesh minus is extracted from the hammer milled tree, which is then placed in a bagging machine and dust is vacuumed from the juniper tree. The juniper tree is then bagged.

A method for producing animal bedding is provided. A juniper tree is cut at ground level, the juniper tree having needles and a trunk. The tree is naturally dried until the needles are brown, then ground using a screen less than 3 inches. The ground juniper is hammer milled and dust of 20 mesh minus is extracted from the hammer milled tree, which is then placed in a bagging machine and dust is vacuumed from the juniper tree. The juniper tree is then bagged.

A method for preheating a beater mill is provided. The method includes: rotating a beater wheel disposed within the beater mill to facilitate circulation of a gas stream between the beater mill and a furnace fluidly connected to each other via both a pulverized fuel conduit and a flue gas recirculation conduit; generating a burner gas via a burner disposed within the flue gas recirculation conduit such that the burner gas joins and heats the gas stream circulating through the beater mill and the furnace; and adjusting at least one of an air supply and a fuel supply to the burner via a controller based at least in part on one of a temperature of the gas stream at an entrance of the beater mill, a temperature of the gas stream at an exit of the beater mill, and an oxygen level within the beater mill.