Abstract: The present invention relates to an air jigging machine for the dry processing of raw materials, particularly coal, comprising at least one material feeding device (1), at least one jigging material carrier (2), which is provided with openings, an air funnel (3), which is arranged below the jigging material carrier (2) and by means of which an air flow can be fed as working air (4) to the jigging material carrier, which working air is composed of a partial flow constantly flowing through the jigging material carrier (2) and a pulsing partial flow superposed thereon, such that the working air (4) can flow through the material fed onto the jigging material carrier (2) and said material can be stratified into a heavy material layer (5) acting as a jig bed and into a light material layer (6) lying thereon, and a discharge device (7) for the heavy material and light material stratified on the jigging material carrier (2) during the jigging process.

Abstract: A pulse valve for generating a high-volume pulsating fluid stream from a fluid supplied to the pulse valve from a pressure-generating unit. Window cut-outs are disposed opposite one another in pairs, in a housing wall, and form a first channel for conducting a constant, stationary sub-stream, a second channel for generating a second sub-stream that forms a basic pulse component, and a third channel for generating a third sub-stream that forms an additional pulse component. A rotatable rotor shaft disposed in the interior of the housing is provided with respective rotor blade assemblies associated with the second and third channels respectively. Upon rotation of the rotor shaft, the rotor blade assemblies, in cooperation with boundary edges of the window cut-outs of the second and third channels, periodically either allow a fluid stream impinging on the pulse valve to pass through the housing, or to interrupt such passage.

Abstract: An air jigging machine for dry processing of raw materials, an air supply conduit for supplying working air to an air funnel, and having a pulsing valve. At least two jigging-material carriers for receiving material from a material-feeding mechanism are configured to consecutively receive therethrough working air from the air funnel and to separate the material into heavy and light material layers. The jigging-material carriers are disposed one above the other and are spaced apart. A wall encloses this intermediate space. At least one bypass airline branches off from the air supply conduit downstream of the pulsing valve, bypasses the lower jigging-material carrier, and communicates with the intermediate space for supplying an additional working airflow thereto. Respective discharge devices are provided for the jigging-material carriers for the material layered thereon during a jigging process.

Abstract: An air sifting apparatus for dry preparation of material comprising an apertured sifted material carrier for receiving material from a material feed device. An air plenum is disposed below the carrier and is comprised of two chambers that are separated from one another and are disposed one after the other in the direction in which the material is conveyed by the carrier. Each chamber has an air inlet for receiving a constant partial air stream. Respective inlet conduits deliver a pulsating air stream to each chamber. The air plenum supplies an air stream that flows through the carrier to loosen and layer the material received thereby into a heavy material layer and a light material layer disposed on the heavy material layer. The air stream is composed of the constant partial air stream and the pulsating air stream.

Abstract: An apparatus for separating out light materials from mineral raw materials is provided. The apparatus includes a charging device that has a charging tube provided with an eccentrically arranged inlet for tangential introduction of raw material. The apparatus also has an inner chamber for separating out coarse sand received from the charging tube, and an outer chamber that serves for sorting out fine sand pursuant to the fluidized bed process. The outer chamber communicates with an overflow chute of the charging tube via an inclined overflow surface. An impingement body is centrally disposed in the inner chamber while leaving free an outer annular gap. The charging tube opens out centrally above the impingement body. A perforated basket, for adjusting flow resistance, is disposed so as to be displaceable in the axis of the charging tube and bridges a space between the impingement body and the end of the charging tube.

Abstract: A jigging machine for treating minerals has a jigging tank with a jigging container and an air chamber. The jigging tank contains water. The air chamber has at least one inlet valve and at least one outlet valve. A compressed air supply is connected to the at least one inlet valve. Compressed air is pulsed via the at least one inlet valve into the air chamber for forcing the water contained in the jigging tank from the air chamber into the jigging container and, after each pulse of compressed air, the water flows back into the air chamber and forces the air out of the air chamber via the at least one outlet valve. The air chamber has an outlet opening positioned below the lowest permissible water level occurring during a jigging pulse. This outlet opening is constantly open during operation of the jigging machine.

Abstract: A rotary piston valve arrangement, for a pneumatic settling tank, including rotary piston valves disposed in a common housing, with a first rotary piston valve being designed for the control of an additive stroke, and a second rotary piston valve being designed for the control of a discharge position. To reduce the amount of air required for controlling the settling tank, an element is provided for periodically shutting off the passage of air between the air inlet opening of the first rotary piston valve and the settling chamber during the time interval of an intake position of the first rotary piston valve and a simultaneous discharge position of the second rotary piston valve.

Abstract: Ring injectors for aerating fluids, useful for example in flotation systems, have a housing with a mixing section, in which air is added to the through-flowing fluid through an annular slot. A core is arranged in the center of the mixing section. An air-solid mix is formed in the mixing section by deposition of air bubbles on solid particles. An annular injector with a slot width (Q.sub.2) that leads into the airing chamber with a minimum opacifying speed of 2.0 m/s at the inlet of the aerating chamber, has an annex mixing and dispersing section (6) with a cross-section that remains the same until the end (12), as well as a middle piece (10) centrally arranged therein also having a constant cross-section, the length of the mixing and dispersing section (6) being 20 times the width of the annular slot (Q.sub.3). The distributing cone (2) and the middle piece (10) can be screwed together or inserted into each other. The air slot can be regulated by spacing rings (13).