A mill includes a housing with a first end portion, a second end portion, and a lateral area disposed therebetween. The housing includes a raw material inlet, an air inlet, a recirculated material inlet, and a material outlet. An impeller is supported by the housing and includes a shaft disposed along the longitudinal axis of the housing, with a plurality of curved blades. A method for milling includes receiving a material of a first size range, introducing the material to an apparatus via a first inlet and introducing air into the apparatus via a second inlet. The method also includes agitating the material via an impeller, where the agitation reduces at least some of the material to a second size range by the time the material reaches an outlet of the apparatus. The processed material is delivered to subsequent processing operations.

A mill includes a housing with a first end portion, a second end portion, and a lateral area disposed therebetween. The housing includes a raw material inlet, an air inlet, a recirculated material inlet, and a material outlet. An impeller is supported by the housing and includes a shaft disposed along the longitudinal axis of the housing, with a plurality of curved blades. A method for milling includes receiving a material of a first size range, introducing the material to an apparatus via a first inlet and introducing air into the apparatus via a second inlet. The method also includes agitating the material via an impeller, where the agitation reduces at least some of the material to a second size range by the time the material reaches an outlet of the apparatus. The processed material is delivered to subsequent processing operations.

The present disclosure relates to a system for a material reducing machine that allows a reducing rotor to be selectively configurable in a plurality of different reducing configurations. The different reducing configurations in which the reducing rotor can be configured can include reducing configurations having reducers located at different positions, reducing configurations having different reducer densities (e.g., different overall densities and different regionalized densities), reducer configurations having different reducer counts, reducer configurations having different reducer patterns, and reducer configurations having different lay-outs.

The present disclosure relates to a system for a material reducing machine that allows a reducing rotor to be selectively configurable in a plurality of different reducing configurations. The different reducing configurations in which the reducing rotor can be configured can include reducing configurations having reducers located at different positions, reducing configurations having different reducer densities (e.g., different overall densities and different regionalized densities), reducer configurations having different reducer counts, reducer configurations having different reducer patterns, and reducer configurations having different lay-outs.

A beater wheel for a pulverizer mill is provided. The beater wheel includes a rotatable hub disc having apertures defined therethrough and a ring disc having respective apertures defined therethrough, and a plurality of tubular ribs, disposed therebetween and weldingly coupled thereto at a tubular first end to the hub disc and at a tubular second end to the ring disc to define respective weld joints thereat. Each respective aperture in the hub disc and ring disc are sized and disposed to allow direct access therethrough to at least one respective weld joint at the respective interior surface of the first and second tubular ends for inspection and testing.

A beater wheel for a pulverizer mill is provided. The beater wheel includes a rotatable hub disc having apertures defined therethrough and a ring disc having respective apertures defined therethrough, and a plurality of tubular ribs, disposed therebetween and weldingly coupled thereto at a tubular first end to the hub disc and at a tubular second end to the ring disc to define respective weld joints thereat. Each respective aperture in the hub disc and ring disc are sized and disposed to allow direct access therethrough to at least one respective weld joint at the respective interior surface of the first and second tubular ends for inspection and testing.

A cutter wheel for use with a stump cutter having a drive assembly includes a drive plate having first and second sides and a perimeter. A cutter is attached to one of the sides, the cutter having a contact surface configured to engage the side. The cutter has a leading surface and a trailing surface, and a leading mounting hole defining a leading axis and a trailing mounting hole defining a trailing axis. A reference line passes through the leading axis and the trailing axis. A portion of the perimeter of the drive plate is in a zone defined by: a pair of radial lines extending from the leading axis at angles of 20 degrees and 40 degrees radially outward from the reference line, and a pair of arcs 0.25 in. radially outward and inward, respectively, from the leading surface.

A cutter wheel for use with a stump cutter having a drive assembly includes a drive plate having first and second sides and a perimeter. A cutter is attached to one of the sides, the cutter having a contact surface configured to engage the side. The cutter has a leading surface and a trailing surface, and a leading mounting hole defining a leading axis and a trailing mounting hole defining a trailing axis. A reference line passes through the leading axis and the trailing axis. A portion of the perimeter of the drive plate is in a zone defined by: a pair of radial lines extending from the leading axis at angles of 20 degrees and 40 degrees radially outward from the reference line, and a pair of arcs 0.25 in. radially outward and inward, respectively, from the leading surface.

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.

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.