This disclosure generally relates to separators for separating a mixture into its fluid and solid material components. More particular, this disclosure relates to separators including a rotatable rotor positioned within a separating chamber.
Conventional separators can be used for separating a mixture that consists, for example, of a solid material and a fluid into its respective constituents. The mixture of the solid material and the fluid is, in particular, supplied to the separator as a continuous conveying flow. The separators, which are also known as centrifugal dryers, are often used in the plastics processing industry. By means of such a separator, a plastic granulate can separated from a water stream conveying the granulate so that the granulate can be isolated for further processing or packaging.
Known separators have a housing with an inlet for supplying the mixture and at least one outlet for discharging the solid material and/or the fluid. Such separators include a separation chamber that comprises at least one inlet area for the mixture to be fed into and at least one discharge opening for emitting the separated solid material. The separation chamber is formed at least in regions by a screen configured to retain the solid material within the separation chamber and allow the fluid to pass through. Arranged within the separation chamber is a rotatably mounted rotor, which, by rotating, causes movement at least of the solid material with a direction of transport substantially along its longitudinal axis or axis of rotation.
The inlet area of the separation chamber, which may have a cylindrical shape, is usually formed on the surrounding wall of the separation chamber. The inlet area often has an incline that directs the material downwards towards the bottom of the separation chamber. Due to the potential energy present in the mixture, the mixture therefore automatically flows into the separation chamber. Because the rotating rotor is arranged in the separation chamber, the mixture experiences a deflection or reversal in movement in another direction upon entering the separation chamber. In particular, this deflection or reversal can cause the mixture to move upwards through the separation chamber. The solid material and at least parts of the fluid are then moved over a predetermined height along the longitudinal axis of the rotor.
The solid material to be separated from the mixture may under certain circumstances have abrasive properties and/or contain fillers, such as glass fibers or rock flour, which themselves have abrasive properties. Due to the deflection movement of the mixture following introduction into the separation chamber and the contact between the solid and the rotor, significantly greater wear may occur in the lower section of the rotor as compared to the upper sections. This wear necessitates maintenance of the separator at increasingly regular intervals, which causes corresponding downtimes of any upstream or downstream components of the separator within a plastics processing system.
As a result, there is a need for a separator that requires less downtime due to rotor wear caused by contact between the solid material of the mixture and the lower section of the rotor.
An embodiment of the present invention includes a separator for separating a mixture that comprises a solid material and a fluid. The separator has a housing having a mixture inlet for receiving a mixture, a first outlet for discharging the solid material, and a second outlet for discharging the fluid, where each of the solid material and the fluid is separated from the mixture at the first and second outlets, respectively. The separator also has a screen positioned within the housing, wherein the screen defines a separation chamber having an inlet configured to receive the mixture and a discharge opening configured to provide the solid material to the first outlet. Further, the separator has a pipe at least partially extending along an inlet axis, where the pipe is in fluid communication with the mixture inlet and the inlet of the separation chamber, and a rotor extending through the separation chamber, where the rotor is configured to rotate about a longitudinal axis such that rotation of the rotor is configured to move the solid material upwards from the inlet to the discharge opening in a transport direction that is substantially parallel to the longitudinal axis. The inlet axis is oriented such that the pipe is configured to direct the mixture upwards through the inlet along a material direction that extends at least partially along the transport direction.
The foregoing summary, as well as the following detailed description, will be better understood when read in conjunction with the appended drawings. The drawings show illustrative embodiments of the invention. It should be understood, however, that the application is not limited to the precise arrangements and instrumentalities shown.
Described herein is a separator 1 that includes a screen 16 defining a separation chamber 12. The separator 1 also includes a rotor 10 extending through the separation chamber 12 and a pipe 38 feeding material to the separation chamber 12 at an inlet 29, where at least a portion of the pipe 38 extends along an inlet axis 1A. Certain terminology is used to describe the separator 1 in the following description for convenience only and is not limiting. The words “right,” “left,” “lower,” and “upper” designate directions in the drawings to which reference is made. The words “inner” and “outer” refer to directions toward and away from, respectively, the geometric center of the description to describe the separator 1 and related parts thereof. The words “upwards” and “downwards” refer to directions in an axial direction A and a direction opposite the axial direction A along the separator 1 and related parts thereof. The terminology includes the above-listed words, derivatives thereof, and words of similar import.
Unless otherwise specified herein, the terms “axial” and “radial” are used to describe the orthogonal directional components of various components of the separator 1, as designated by the axial direction A and radial direction R. It should be appreciated that while the axial direction A is illustrated as extending along a vertical plane and the radial direction R is illustrated as extending along a horizontal plane, the planes that encompass the various directions may differ during use. Also, though the radial direction R may be shown as extending in a certain direction, the radial direction R may comprise any direction extending through a plane that is perpendicular to the axial direction A.
Now referring to
The rotor 10 is preferably rotationally coupled to a drive 18. In one embodiment, the drive 18 is an electric motor, though other drives for rotating the rotor 10 are contemplated. The drive 18 can be controlled so as to adjust the rotational speed of the rotor 10 in relation to the flow of material entering the separation chamber 12. The rotor 10 includes a plurality of transport elements 20 extending radially outwards, where the transport elements 20 are arranged in several columns along the rotor 10. The columns of transport elements 20 extend along the axial direction A and are circumferentially spaced apart about the longitudinal axis L of the rotor 10. The transport elements 20, also referred to as lifting elements, are inclined and angularly offset with respect to the longitudinal axis L of the rotor 10. The body of each transport element 20 can be offset from the longitudinal axis L of the rotor 10 by an angle that can be from about 20 degrees to about 70 degrees. The body of each transport element 20 can also be at least partially curved and/or angled to cause a gradual or stepwise deflection of the solid material as it moves in the transport direction T, as will be described below. The outer surface of each transport element 20 can by contoured to match the contour of the inner surface of the screen 16. Though one particular arrangement of transport elements 20 and a particular number of transport elements 20 are shown, it is contemplated that the rotor 10 can include other arrangements and numbers of transport elements 20 in other embodiments. For example, the rotor can have four, five, six, or more columns of transport elements 20 uniformly distributed about the circumference of the rotor 10.
On the outer circumference of the rotor 10, the transport elements 20 form an outer conveying section in combination with the circumferentially surrounding screen 16 for moving the solid material through the separator 1. When the rotor 10 rotates about the longitudinal axis L, the transport elements 20 also rotate about the longitudinal axis L and are configured to move the solid material upwards in a direction of transport T that is substantially parallel to the longitudinal axis L. In the embodiment shown, the direction of transport T runs approximately along the axial direction A from the lower end 24 of the separation chamber 12 to the upper end 26 of the separation chamber 12. Extending outwards from the surrounding wall 14 and upwards from a base wall 32, a fluid-impermeable baffle surface 17 can be formed, which can deflect the mixture entering the separation chamber 12 at the lower end 24 in a circumferential direction. In operation, the solid is conveyed from an inlet area 28 at the lower end 24 of the separation chamber 12 towards a discharge opening 30 at the upper end 26 of the separation chamber 12 by the rotor 10 and associated transport elements 20. The discharge opening 30 is connected to the second outlet 6b for discharging the separated solid material. Simultaneously, a centrifugal force acting on the mixture in the radial direction R as the rotor 10 rotates will force the liquid radially outwards through the screen 16, and thus out of the separation chamber 12. This separation of the liquid from the solid material can occur over the entire height of the separation chamber 12, such that once the solid material reaches the upper end 26 of the separation chamber 12, it is completely separated from the liquid. Once the liquid passes radially outwards through the screen 16, it can fall downwards under the force of gravity and exit the separator 1 through the first outlet 6a.
Now referring to
As
Now referring to
Now referring to
As can be seen in
A mixture to be separated within the separation chamber flows into the distribution chamber 44 via the pipe 38. The mixture is then distributed uniformly via the annular channel 48 in the distribution chamber 44 and then passes through the inlets 50 into the separation chamber 12. Depending upon the number of axial apertures, the apertures have cross-sections suitably adapted to the cross-section of the pipe 38. This prevents the mixture from piling up in the distribution chamber 44.
The separator 1 and constituent components described above achieve the underlying aim for a separator of separating a mixture consisting of a solid material and a fluid, which can be plastic granulate and water. In particular, the inlet areas 28a-28d and pipe 38 of the separator 1 are formed in such a way that, when the mixture enters the separation chamber 12, it performs a movement in the material direction M having at least one axial component relative to the longitudinal axis L of the rotor 10, where the material direction M extends at least partially in the transport direction T. These features help reduce the deflection of the mixture as it enters the separation chamber 12, and can preferably cause a deflection movement of the mixture to no longer take place. As a result, the wear upon features of the separator 1, in particular, the lower section of the rotor 10, is thus reduced to a minimum, even in the case of a separation process of a mixture containing solid material with abrasive properties from a fluid. The service life of the rotor 10 and other component parts and components which come into contact with the mixture and the solid to be separated therefrom can thus be lengthened, and the distances between possible maintenance intervals on the rotor can be increased.
While various inventive aspects, concepts and features of the inventions may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present inventions. Still further, while various alternative embodiments as to the various aspects, concepts, and features of the inventions—such as alternative materials, structures, configurations, methods, circuits, devices and components, software, hardware, control logic, alternatives as to form, fit and function, and so on—may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts or features into additional embodiments and uses within the scope of the present inventions even if such embodiments are not expressly disclosed herein. Additionally, even though some features, concepts or aspects of the inventions may be described herein as being a preferred arrangement or method, such description is not intended to suggest that such feature is required or necessary unless expressly so stated. Still further, exemplary or representative values and ranges may be included to assist in understanding the present disclosure; however, such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly stated. Moreover, while various aspects, features, and concepts may be expressly identified herein as being inventive or forming part of an invention, such identification is not intended to be exclusive, but rather there may be inventive aspects, concepts, and features that are fully described herein without being expressly identified as such or as part of a specific invention, the scope of the inventions instead being set forth in the appended claims or the claims of related or continuing applications. Descriptions of exemplary methods or processes are not limited to inclusion of all steps as being required in all cases, nor is the order that the steps are presented to be construed as required or necessary unless expressly so stated.
While the invention is described herein using a limited number of embodiments, these specific embodiments are not intended to limit the scope of the invention as otherwise described and claimed herein. The precise arrangement of various elements and order of the steps of articles and methods described herein are not to be considered limiting. For instance, although the steps of the methods are described with reference to sequential series of reference signs and progression of the blocks in the figures, the method can be implemented in a particular order as desired.
Number | Date | Country | Kind |
---|---|---|---|
17199847.9 | Nov 2017 | EP | regional |
This application is a U.S. National Stage Application of International Patent Application No. PCT/US2018/058973, filed Nov. 2, 2018, which claims priority to European Patent Application No. 17199847.9, filed Nov. 3, 2017, the entire disclosures of both of which are hereby incorporated by reference as if set forth in their entireties herein.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/US2018/058973 | 11/2/2018 | WO | 00 |