About: Screw conveyor is a(n) research topic. Over the lifetime, 4290 publication(s) have been published within this topic receiving 16655 citation(s).
17 Aug 1994-
Abstract: A vertically oriented centrifuge (1) swivably engaged to a support structure (2) so as to enable the centrifuge (1) to attain an optimal operational attitude The centrifuge includes a bowl (56), a screw conveyor (65) disposed within the bowl (56), a hub (64) disposed within the upper portion of the screw conveyor (65) wherein the screw conveyor (65) and hub (64) define a separation chamber (98), and a plurality of separating discs (66) disposed in the separation chamber (98) and arranged in superimposed layers upon the hub (64)
10 Aug 2009-Powder Technology
Abstract: Screw conveyors are used extensively in agriculture and industry for transporting and/or elevating bulk materials over short to medium distances. They are very effective conveying devices for dry particulate solids, giving good control over the throughput. Despite their apparent simplicity, the mechanics of the transportation action is very complex and designers have tended to rely heavily on empirical performance data. The performance of a screw conveyor is affected by the operating conditions, such as: the rotational speed of the screw; the inclination of the screw conveyor; and the volumetric fill level of the bulk material. In this paper we examine how these operating conditions influence the performance of a screw conveyor by applying the Discrete Element Method (DEM) to simulate a single-pitch screw conveyor with periodic boundary conditions. The DEM modelling gives predictions of screw conveyor performance in terms of variations of: particle speeds, mass flow rate, energy dissipation and power consumption, due to changes in the operating conditions.
Alan W. Roberts1•Institutions (1)
03 Aug 1999-Powder Technology
Abstract: This paper is concerned with the volumetric performance of enclosed screw conveyors with particular reference to the influence of vortex motion. Vortex motion arises as a result of internal friction, friction between the granular material and surface of the helical blade, and the infinitely variable helix angle of the helical flight from the outer periphery of the blade to the shaft. The vortex motion, together with the degree of fill, govern the volumetric efficiency and, hence, the volumetric throughput. An analysis of the vortex motion in vertical or steeply inclined screw or auger conveyors is presented. It is shown the vortex motion is characterised by the tangential component of the absolute grain velocity being substantially constant with the radial position of a point on the blade. On this basis, an expression for the volumetric efficiency is derived. The volumetric throughput can then be predicted. The paper also presents results from an experimental screw conveyor where it is shown that the analytical predictions correlate very closely to the measured results.
01 Sep 2001-Journal of Engineering Mechanics-asce
Abstract: A numerical analysis using the 3D distinct element method (DEM) is conducted in order to examine the performance of screw conveyors. In particular, the simulation of horizontal and vertical types is studied. The results are compared with previous work and empirical equations. As a result, it is determined that this method is sufficiently well developed and useful to analyze the performance of screw conveyors.
09 Jan 2004-
Abstract: A mobile self-contained apparatus and process for grinding, grating, macerating, chemically disinfecting, and drying infectious waste material on-site is disclosed. A trailer (10) contains a hopper (27) and a system of grinder/graters, enclosed conveyors, drying and filter apparatus, and sources of power, chemical disinfectant, and fresh water. Bagged infectious waste material in a cart (C) is lifted and dumped into a hopper (27), fed to a first grinder/grater (28, 29), ground and grated into particles, immersed in a sodium hypochlorite (hypochlorous acid) chemical disinfectant solution, and conveyed by an enclosed upwardly inclined screw conveyor (34) to a second grinder/grater (43). The particles are sprayed one or more times with the disinfectant and thoroughly mixed together as they are conveyed in the inclined conveyor (34) into the second grinder/grater (43) operating at a higher speed than the first and further ground, grated, and macerated into smaller particles, and air dried to produce a dry confetti-like material which is unrecognizable as to the source. The confetti-like material is conveyed by an enclosed horizontal screw conveyor (45) to an enclosed vertical screw conveyor (47) where it is passed upwardly to an enclosed rotatable discharge screw conveyor (50) which discharges the confetti-like material into a receptacle. The enclosed system operates under negative pressure produced by a suction fan which draws the air within the system through a hepa-filter (40) to remove chemical fumes, airborne dust, odors and bacteria.