Centrifugal separation of particles from a fluid stream - e.g. from air in a pneumatic conveying system

摘要

In a process for separating particles from a fluid carrier stream, where the particles which are of greater density than the carrier flow, are carried by this flow via the inlet region of a circular cross-section housing, to pass along its axial extent, with the particles leaving the housing via a discharge outlet and proceeding to a fluid-tight collector vessel, or being taken off via a lock, whilst the fluid stream which is almost or totally free of particles via a central tube which is spaced apart from the housing outlet, so that the flow down the central tube moves opposite to the flow direction of the particulate laden stream. The novelty is that the particles before discharge to the collector, or from the discharge lock, proceed with the carrier stream under the influence of a motor-driven impeller wheel whose axis of rotation is aligned coaxially to the housing axis, with the periphery of the impeller wheel extending to seal against the radial confine of the housing. Particles are radially accelerated with the carrier stream and caused to rotate with high centrifugal acceleration. The particles are then discharged via an outlet arranged perpendicular to the housing axis in the peripheral region of the impeller wheel, with the carrier fluid leaving via the central cyclone tube. The position of the housing axis, and the rotational axis of the impeller wheel with which it is coaxial, can adopt a preferred inclination between the horizontal and vertical positions. The separation of the central tube and the axis of the housing is adjustable, and the centrifugal acceleration is variable by means of rotation speed control on the drive of the impeller wheel. USE/ADVANTAGE - For separation of particulates from a fluid carrier stream e.g. from air in a pneumatic conveying system. There is improved performance over cyclone separators, where performance can be affected by variations in changes in dynamic viscosity and solids loading of the carrier fluid, and in the particle size distribution.