A powder classification apparatus (10; 110; 210) includes a first chamber (12; 112; 212) that includes a fluidized bed and has an inlet (16; 116; 216A) and an outlet (18; 118; 218), the inlet (16; 116; 216A) configured to receive a gas (G) and distribute the gas (G) in a uniform flow through the first chamber (12; 112; 212), the first chamber (12; 112; 212) configured to receive a powder (P) and the gas (G) and create a fluidization zone, the outlet (18; 118; 218) configured to allow at least a portion of the powder (P) to exit the first chamber (12; 112; 212); and a second chamber (14; 114; 214) having a powder inlet (24; 124; 224) configured to accept at least a portion of the powder (P) from the outlet (18; 118; 218) in the first chamber (12; 112; 212) caused by at least a portion of the powder (P) being ejected from the first chamber (12; 112; 212) by the gas (G).

A powder classification apparatus (10; 110; 210) includes a first chamber (12; 112; 212) that includes a fluidized bed and has an inlet (16; 116; 216A) and an outlet (18; 118; 218), the inlet (16; 116; 216A) configured to receive a gas (G) and distribute the gas (G) in a uniform flow through the first chamber (12; 112; 212), the first chamber (12; 112; 212) configured to receive a powder (P) and the gas (G) and create a fluidization zone, the outlet (18; 118; 218) configured to allow at least a portion of the powder (P) to exit the first chamber (12; 112; 212); and a second chamber (14; 114; 214) having a powder inlet (24; 124; 224) configured to accept at least a portion of the powder (P) from the outlet (18; 118; 218) in the first chamber (12; 112; 212) caused by at least a portion of the powder (P) being ejected from the first chamber (12; 112; 212) by the gas (G).

A combustion ash handling method of handling combustion ash discharged from a combustion furnace that combusts a petroleum-based fuel includes: separating the combustion ash into a heavy component and a light component by a dry-type separation technique; feeding the light component to the combustion furnace as a fuel; and recovering the heavy component. A metal such as vanadium is separated and extracted from the heavy component of the combustion ash.

A combustion ash handling method of handling combustion ash discharged from a combustion furnace that combusts a petroleum-based fuel includes: separating the combustion ash into a heavy component and a light component by a dry-type separation technique; feeding the light component to the combustion furnace as a fuel; and recovering the heavy component. A metal such as vanadium is separated and extracted from the heavy component of the combustion ash.

Sifting apparatuses for stratifying raw material including a material feed-in device, a material support unit, a gas plenum, a discharge control mechanism, and a reservoir are described. The material support unit receives material from the material feed-in device and has a surface with a plurality of openings for a gaseous medium introduced from underneath the material support unit, thereby effecting loosening and stratification of the material into a layer of relatively heavier material, and a layer of relatively lighter material atop the relatively heavier material. The introduced gaseous medium originates in a pump, is collected in a pressurized reservoir, and is controlled by a metered valve prior to introduction to the material support unit.

Sifting apparatuses for stratifying raw material including a material feed-in device, a material support unit, a gas plenum, a discharge control mechanism, and a reservoir are described. The material support unit receives material from the material feed-in device and has a surface with a plurality of openings for a gaseous medium introduced from underneath the material support unit, thereby effecting loosening and stratification of the material into a layer of relatively heavier material, and a layer of relatively lighter material atop the relatively heavier material. The introduced gaseous medium originates in a pump, is collected in a pressurized reservoir, and is controlled by a metered valve prior to introduction to the material support unit.

A sluice box is described comprising two walls, and a plurality of riffles. Riffles can have a first portion that extends below the bottom panel of a sluice box (or the bottom of a flow), and a second portion that extends above the bottom panel of a sluice box (or the bottom of a flow). By creating a catch in a riffle by having a portion of the riffle extend below a bottom panel of a sluice box, heavier minerals are not washed away as quickly, if at all, as with other sluices.

A sifting apparatus for stratifying raw material includes a material feed-in device, a material support unit, a gas plenum, and a discharge control device. The material support unit receives material from the material feed-in device and has a surface having a plurality of openings for a gaseous medium introduced from underneath the material support unit, thereby effecting loosening and stratification of the material into a layer of relatively heavier material, and a layer of relatively lighter material atop the heavier material. The introduced gaseous medium originates in a pump, is collected in a pressurized reservoir and is controlled by a metered valve prior to introduction to the material support unit.

A classification system using a fluidized bed according to the present invention includes: a fluidized bed classifier supplied with powder containing particles of different sizes, which entrains the powder into the fluidized gas, and then discharges coarse powder through a coarse powder outlet positioned in its lower portion. The system further includes a cyclone communicating with an upper portion of the fluidized bed classifier, which collects and discharges fine powder contained in the fluidized gas transferred from the fluidized bed classifier to a fine powder outlet positioned in its lower portion. Additionally, the system further includes a plurality of internal structures positioned in the fluidized bed in the fluidized bed classifier which reduce a size of a bubble of the fluidized gas.

A classification system using a fluidized bed according to the present invention includes: a fluidized bed classifier supplied with powder containing particles of different sizes, which entrains the powder into the fluidized gas, and then discharges coarse powder through a coarse powder outlet positioned in its lower portion. The system further includes a cyclone communicating with an upper portion of the fluidized bed classifier, which collects and discharges fine powder contained in the fluidized gas transferred from the fluidized bed classifier to a fine powder outlet positioned in its lower portion. Additionally, the system further includes a plurality of internal structures positioned in the fluidized bed in the fluidized bed classifier which reduce a size of a bubble of the fluidized gas.