A process for reforming the fly ash, including the heating step that heats a raw fly ash powder containing the unburned carbon at a temperature of 780 to 1000° C. to decrease the amount of the unburned carbon contained in the raw fly ash powder; the classifying step that introduces the heat-treated fly ash containing the unburned carbon in decreased amounts obtained through the heating step into a classifying apparatus in the state of being heated at a high temperature so as to separate the fly ash into a coarse powder and a fine powder; the fine powder recovering step that recovers the fine powder of the heat-treated fly ash obtained through the classifying step by using a dust-collecting apparatus; and the milling step that mills the coarse powder of the heat-treated fly ash obtained through the classifying step until a 45 μm sieve residue becomes not more than 34% by mass, and then recovers the milled powder.

A secondary impurity-removal recycling system for refining cotton is provided. A first feeding opening is set on the side of the first bin shell, in which the first drum is movably installed, and the first drum is tube shaped. A first mesh is set on the peripheral wall of the first drum, and a first scraper is set at the first feeding opening inside the first bin shell. One end of the first drum is provided with a first impurity-discharging pipe, the outer periphery of which is provided with a first annular hump. The first connecting sleeve is installed on the outer wall of the first bin shell, and the first impurity-discharging pipe is movably stuck in the first connecting sleeve through the first annular hump, and communicates with the first connecting sleeve. The first induced draft fan communicates with the first connecting sleeve through a first air duct.

A centrifugal separator including a separator housing and a separator wheel revolving in the housing. The separator housing has an inlet for material, a coarse material outlet, and a fine material outlet. The wheel is formed by a drum and a wheel shaft, which supports the drum and rotates around a horizontal axis. The circumferential jacket surface of the drum is interrupted such that it sets the material to be separated, which hits the drum on the outer jacket side, into rotation during operation and the separation air flows through it in the radially inwards direction. The fine material outlet is arranged on the end of the drum and fine material is discharged from the interior of the drum into the fine material outlet via the free front face of the drum. The wheel shaft consists of two parts, which are not directly connected to one another in a supporting manner.

A secondary impurity-removal recycling system for refining cotton is provided. A first feeding opening is set on the side of the first bin shell, in which the first drum is movably installed, and the first drum is tube shaped. A first mesh is set on the peripheral wall of the first drum, and a first scraper is set at the first feeding opening inside the first bin shell. One end of the first drum is provided with a first impurity-discharging pipe, the outer periphery of which is provided with a first annular hump. The first connecting sleeve is installed on the outer wall of the first bin shell, and the first impurity-discharging pipe is movably stuck in the first connecting sleeve through the first annular hump, and communicates with the first connecting sleeve. The first induced draft fan communicates with the first connecting sleeve through a first air duct.

This powder-classifying apparatus has: a centrifugation chamber configured so as to be sandwiched between two opposing members; an air supply unit that supplies air into the centrifugation chamber and generates a swirl flow; a raw material supply unit that supplies raw-material powder into the swirl flow; a fine powder recovery unit having an opening part through which air that includes fine powder classified within the centrifugation chamber is ejected to outside of the centrifugation chamber; a coarse powder recovery unit provided to the outer edge part of the centrifugation chamber, for ejecting classified coarse powder to outside of the centrifugation chamber; and an annular slit provided to at least one of the members that constitute the centrifugation chamber, the slit being provided in a region between the center part of the centrifugation chamber and the outer edge part.

The present invention relates to methods for beneficiating a banded coal of the type wherein a substantial portion of the ash constituents is within the cleats. The method includes subjecting a comminuted coal feed, including coal and ash and having a particle size of about −13.5 mm, to a density separation process to separate the comminuted coal feed, using a separating gravity value of from about 1.35 up to about 1.9, into a beneficiated coal fraction and an ash containing gangue fraction. The method may include the initial steps of subjecting a coarse coal having a size of up to −150 mm to a density separation process to separate the coarse coal into an initial light coal-containing fraction and an initial heavy ash containing gangue fraction; and subjecting at least a portion of the initial light coal-containing fraction to a comminution process to form the comminuted coal feed. The invention extends to a coal product produced by said methods.

The present invention relates to methods for beneficiating a banded coal of the type wherein a substantial portion of the ash constituents is within the cleats. The method includes subjecting a comminuted coal feed, including coal and ash and having a particle size of about −13.5 mm, to a density separation process to separate the comminuted coal feed, using a separating gravity value of from about 1.35 up to about 1.9, into a beneficiated coal fraction and an ash containing gangue fraction. The method may include the initial steps of subjecting a coarse coal having a size of up to −150 mm to a density separation process to separate the coarse coal into an initial light coal-containing fraction and an initial heavy ash containing gangue fraction; and subjecting at least a portion of the initial light coal-containing fraction to a comminution process to form the comminuted coal feed. The invention extends to a coal product produced by said methods.

A process for reforming the fly ash, including the heating step that heats a raw fly ash powder containing the unburned carbon at a temperature of 780 to 1000 C. to decrease the amount of the unburned carbon contained in the raw fly ash powder; the classifying step that introduces the heat-treated fly ash containing the unburned carbon in decreased amounts obtained through the heating step into a classifying apparatus in the state of being heated at a high temperature so as to separate the fly ash into a coarse powder and a fine powder; the fine powder recovering step that recovers the fine powder of the heat-treated fly ash obtained through the classifying step by using a dust-collecting apparatus; and the milling step that mills the coarse powder of the heat-treated fly ash obtained through the classifying step until a 45 m sieve residue becomes not more than 34% by mass, and then recovers the milled powder.

An apparatus for classifying fine particles in slurry provides a sharp particle size distribution with few mixed coarse particles and high classification accuracy. The apparatus includes a rotor (15) including classification chambers (17) between blades (16) radially arranged at circumferentially regular intervals, and classifies particles so that a classified particle size is constant in an entire radial region from an outer periphery to an inner periphery of the classification chamber. The blade (16) of the rotor has a circumferential thickness t(d) increasing toward the outer periphery, and the classification chamber (17) has a width increasing toward the inner periphery.

An apparatus for classifying fine particles in slurry provides a sharp particle size distribution with few mixed coarse particles and high classification accuracy. The apparatus includes a rotor (15) including classification chambers (17) between blades (16) radially arranged at circumferentially regular intervals, and classifies particles so that a classified particle size is constant in an entire radial region from an outer periphery to an inner periphery of the classification chamber. The blade (16) of the rotor has a circumferential thickness t(d) increasing toward the outer periphery, and the classification chamber (17) has a width increasing toward the inner periphery.