The invention relates to a screening device and a method for screening powders. The device comprises a screening space comprising a first chamber and a second chamber, which chambers are arranged adjacent and have a common partition wall. The device comprises a screen which is placed obliquely or vertically in the screening device, wherein the screen forms at least a part of the common partition wall. The first chamber comprises a raw material inlet, a drive gas inlet, a float gas unit, and a residual particle outlet. The second chamber comprises a product material outlet and a rotatable blade, wherein the blade comprises nozzles which are configured for blowing gas against the screen. In addition, the invention relates to an assembly comprising a first and second screening device, wherein the product material outlet of a first screening device is connected to the raw material inlet of the second screening device.

Disclosed is a particle separation method for separating particles from a mixture. Particles are processed with simultaneous forces acting on particle mass and particle size. The particles are processed by free fall of particles into a side wind or gas flow, to separate the particles by density, establishing the gas flow velocity to reach a distance point of separation of the materials by density. The particles are separated into lots of similar size difference to prevent mixing of bigger particles of low density with small particles of high density based on the processing of the materials.

Disclosed is a particle separation method for separating particles from a mixture. Particles are processed with simultaneous forces acting on particle mass and particle size. The particles are processed by free fall of particles into a side wind or gas flow, to separate the particles by density, establishing the gas flow velocity to reach a distance point of separation of the materials by density. The particles are separated into lots of similar size difference to prevent mixing of bigger particles of low density with small particles of high density based on the processing of the materials.

In order to provide an airflow sorting device having high accuracy and easy adjustment properties with a simple configuration, there are provided a conduit which has a central shaft line and which lets an object to be sorted to fall due to gravity on the inside of the conduit along the central shaft line; an air supply port which is provided at a lower part of the conduit and configured to blow air upward along the central shaft line; a suction port which is provided above the air supply port of the conduit and is an opening oriented downward of a suction pipe provided parallel to the central shaft line; and an input port provided above the suction port of the conduit through which the object to be sorted is input into the periphery of the suction pipe which is in the conduit. Sorting is performed in the sorting device according to whether or not the object to be sorted is being suctioned by the suction port together with a part or the entirety of an airflow generated in the conduit by the air blown from the air supply port, and an airflow adjusting body which is provided below the suction port in the conduit and blocks a falling path of the object to be sorted which falls due to gravity, is provided, and the airflow adjusting body includes: a vertex on the central shaft line; and an inclined surface having a sectional shape, sectional areas of which are similar to each other and increase in size downward, and a drag force which acts on the object to be sorted which falls due to gravity increases downward from the suction port.

The invention is used in various branches of industry, in particular in agriculture for preparing seeds for sowing and for selection purposes. The method of separating a granular mixture in a flowing medium is based on a gravitational supply of particles, with an aerodynamic, monotonously increasing action thereon with a cascade of flat jets, said cascade being stabilized in terms of pressure and discharge. Large impurities are removed from the granular mixture beforehand, and stable parameters are maintained in the separation chamber. The device comprises a vibrating screen, an adjustable hopper with an agitator and a vibrating chute, a generator of a cascade of flat jets, which is connected to a drive for supplying air under pressure, a fraction collector and a separation chamber. The output of the separation chamber is covered with a filtering element in the form of a rotating drum with a calibrating sifter on the surface, said sifter being connected to a cyclone.

A compact dedusting apparatus induces air flow through the housing by a vacuum generator mounted within the housing. The discharge of dust and debris can be passed through a conduit to a remote location without losing air flow velocity to facilitate the use of the compact dedusting apparatus within a clean room. The metering device is formed from stainless steel and mounted on a spring-loaded mounting plate to permit vertical movement of the metering device when a jam of the particulate material is encountered. The metering device can be driven by a low torque stepper motor operable at selectively variable speeds to control the flow rate of the particulate material. The discharge transition is formed with an enlarged cross-sectional area compared to the shape of the Venturi zone so that carryover pellets can be returned to the product flow instead of being lost with the dirty air discharge.

A compact dedusting apparatus induces air flow through the housing by a vacuum generator mounted within the housing. The discharge of dust and debris can be passed through a conduit to a remote location without losing air flow velocity to facilitate the use of the compact dedusting apparatus within a clean room. The metering device is formed from stainless steel and mounted on a spring-loaded mounting plate to permit vertical movement of the metering device when a jam of the particulate material is encountered. The metering device can be driven by a low torque stepper motor operable at selectively variable speeds to control the flow rate of the particulate material. The discharge transition is formed with an enlarged cross-sectional area compared to the shape of the Venturi zone so that carryover pellets can be returned to the product flow instead of being lost with the dirty air discharge.

A compact dedusting apparatus induces air flow through the housing by a vacuum generator mounted within the housing. The discharge of dust and debris can be passed through a conduit to a remote location without losing air flow velocity to facilitate the use of the compact dedusting apparatus within a clean room. The metering device is formed from stainless steel and mounted on a spring-loaded mounting plate to permit vertical movement of the metering device when a jam of the particulate material is encountered. The metering device can be driven by a low torque stepper motor operable at selectively variable speeds to control the flow rate of the particulate material. The discharge transition is formed with an enlarged cross-sectional area compared to the shape of the Venturi zone so that carryover pellets can be returned to the product flow instead of being lost with the dirty air discharge.

A compact dedusting apparatus induces air flow through the housing by a vacuum generator mounted within the housing. The discharge of dust and debris can be passed through a conduit to a remote location without losing air flow velocity to facilitate the use of the compact dedusting apparatus within a clean room. The metering device is formed from stainless steel and mounted on a spring-loaded mounting plate to permit vertical movement of the metering device when a jam of the particulate material is encountered. The metering device can be driven by a low torque stepper motor operable at selectively variable speeds to control the flow rate of the particulate material. The discharge transition is formed with an enlarged cross-sectional area compared to the shape of the Venturi zone so that carryover pellets can be returned to the product flow instead of being lost with the dirty air discharge.

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.