A method is disclosed. The method includes depositing a source material (M) consisting of blast furnace slag into a closed-loop centrifugal air classifying system (10, 10, 10) and utilizing the closed-loop centrifugal air classifying system (10, 10, 10) for processing the blast furnace slag into a processed blast furnace slag material (Mp). A closed-loop centrifugal air classifying system (10, 10, 10) is also disclosed.

A method is disclosed. The method includes depositing a source material (M) consisting of blast furnace slag into a closed-loop centrifugal air classifying system (10, 10, 10) and utilizing the closed-loop centrifugal air classifying system (10, 10, 10) for processing the blast furnace slag into a processed blast furnace slag material (Mp). A closed-loop centrifugal air classifying system (10, 10, 10) is also disclosed.

A method of increasing volume ratio of magnetic particles in a MnBi alloy includes operating a jet miller fed with a MnBi alloy powder containing magnetic particles and non-magnetic particles with gas flow parameters selected such that, only for the magnetic particles, a gas drag force is greater than a centrifugal force within the jet miller to separate the magnetic particles from the non-magnetic particles.

A powder classifying apparatus for classifying powder that has a granularity distribution and recovering fine powder has: a casing provided with two disc-shaped members and a surrounding wall member, a disc-shaped hollow section for classifying powder using a spinning airflow in the interior thereof being formed on the inner side of the casing; at least one powder supply opening for supplying powder into the disc-shaped hollow section; a discharge section for discharging air including fine powder discharged from the disc-shaped hollow section; a recovery unit formed in the thickness-wise center of the surrounding wall member of the casing and provided with a slit-shaped opening for recovering coarse powder discharged from the disc-shaped hollow section; and two air introduction units provided with a plurality of air introduction devices for introducing air into the disc-shaped hollow section in order to form the rotational airflow inside the disc-shaped hollow section.

A powder classifying apparatus for classifying powder that has a granularity distribution and recovering fine powder has: a casing provided with two disc-shaped members and a surrounding wall member, a disc-shaped hollow section for classifying powder using a spinning airflow in the interior thereof being formed on the inner side of the casing; at least one powder supply opening for supplying powder into the disc-shaped hollow section; a discharge section for discharging air including fine powder discharged from the disc-shaped hollow section; a recovery unit formed in the thickness-wise center of the surrounding wall member of the casing and provided with a slit-shaped opening for recovering coarse powder discharged from the disc-shaped hollow section; and two air introduction units provided with a plurality of air introduction devices for introducing air into the disc-shaped hollow section in order to form the rotational airflow inside the disc-shaped hollow section.

A device for separating particles contained in a gas stream for selective additive manufacturing and a selective additive manufacturing apparatus are disclosed. The device comprises at least one dry-type aeraulic separator comprising a separating turbine, a speed of rotation of which is variable. The dry-type aeraulic separator selects the particles contained in the gas stream according to a particle size depending on the speed of rotation of the separating turbine. The device also comprises a device for extracting the particles. The dry-type aeraulic separator and the extraction device are in fluidic communication such that a gas stream exiting the dry-type aeraulic separator circulates through the extraction device and such that the gas stream exiting the extraction device circulates through the dry-type aeraulic separator. The device also comprises a device for circulating the gas stream between the dry-type aeraulic separator and the extraction device.

A device for separating particles contained in a gas stream for selective additive manufacturing and a selective additive manufacturing apparatus are disclosed. The device comprises at least one dry-type aeraulic separator comprising a separating turbine, a speed of rotation of which is variable. The dry-type aeraulic separator selects the particles contained in the gas stream according to a particle size depending on the speed of rotation of the separating turbine. The device also comprises a device for extracting the particles. The dry-type aeraulic separator and the extraction device are in fluidic communication such that a gas stream exiting the dry-type aeraulic separator circulates through the extraction device and such that the gas stream exiting the extraction device circulates through the dry-type aeraulic separator. The device also comprises a device for circulating the gas stream between the dry-type aeraulic separator and the extraction device.