Slurry purification system equipped with a purifier dilution device and method for purifying slurry thereby

Abstract

A clarification system for removing solid debris and contaminants from a feed slurry includes a clarifier that functions to separate the feed slurry into a receiving slurry and a reject slurry, the reject slurry containing the solid debris and contaminants. The clarification system further includes a diluter fluidly coupled to a reject outlet of the clarifier. The diluter includes a dilution water hydrocyclone having a dilution water inlet, a cyclone flow section, an underflow outlet at a downstream end of the cyclone flow section, and a reject slurry inlet at an upper portion of the hydrocyclone. The dilution water hydrocyclone further includes a flow director disposed between the dilution water inlet and the reject slurry inlet and that functions to direct a flow of dilution water from the dilution water inlet axially at least toward the cyclone flow section.

Description

Description of Related Applications

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 62 / 939,253, filed on November 22, 2019, entitled "Slurry Purification System with Dilution Device and Method of Purifying Slurry Thereby", the entire contents of which are incorporated herein by reference.

Technical Field

[0002] This specification generally relates to purification systems for removing solid debris and contaminants from slurries, and more particularly to hydrocyclone purification systems having a dilution device and methods of purifying slurries using such purification systems.

Background Art

[0003] In many industries, slurries are prepared and processed. For example, in the paper industry, in the papermaking process, it is necessary to produce pulp, which is a slurry containing a solid suspension of fibers such as cellulose fibers or other fibers in water. This pulp can contain solid contaminants of various concentrations and sizes, such as wood chips, fiber bundles, metal pieces, cured adhesives, sand, or other contaminants, depending on the source of the fibers. For example, increasing the use of recycled paper as a source of fibers will increase the amount of cured adhesives, metal pieces, sand, and wood chips present in the pulp. Slurries in other industries will contain other types of solid debris and contaminants. These solid contaminants can degrade the quality of the slurry and / or disrupt downstream processes.

[0004] Before introducing the pulp into the papermaking process or before further processing the slurry, the slurry is generally "purified" to remove these solid fragments and / or contaminants from the slurry. The purification of the slurry can be carried out by introducing the slurry into a purification system equipped with at least one hydrocyclone purifier. The cyclone fluid flow generated by the hydrocyclone causes the denser solid contaminants and fragments to flow outward to the outer wall of the hydrocyclone by centrifugal force, while the less dense purified slurry moves towards the center. The purified slurry exits from the accepted slurry outlet of the hydrocyclone, while the denser solid fragments and contaminants descend along the outer wall towards the waste outlet. Therefore, the less dense slurry exiting the hydrocyclone purifier from the overflow outlet will be substantially free of solid fragments and contaminants. The solid fragments and contaminants are discharged from the hydrocyclone purifier as part of the waste slurry.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Due to the high centrifugal force in the hydrocyclone and the higher slurry viscosity resulting from the higher concentration of solid fragments and contaminants in the waste slurry, the waste slurry is likely to clog at the underflow outlet where it is discharged from the hydrocyclone. Dilution water can be added to the waste slurry close to the underflow outlet of the hydrocyclone. However, due to the turbulent mixing caused by introducing the dilution water close to the underflow outlet, at least some of the solid fragments and / or contaminants can flow backward into the hydrocyclone purifier, especially into the flow of the less dense slurry. This can reduce the separation efficiency of the hydrocyclone purifier and may result in leakage of solid fragments and / or contaminants into the downstream process.

[0006] Accordingly, there is a continuing need for a purification system for removing solid fragments and / or contaminants from a slurry. Specifically, there is a continuing need for a purification system having a dilution device that can reduce clogging of the waste outlet of a hydrocyclone purifier while reducing or preventing some of the solid fragments and / or contaminants from being reintroduced into the purifier.

Means for Solving the Problems

[0007] The purification system of the present disclosure includes a purifier and a dilution device coupled to the waste outlet of the purifier. The dilution device may include a dilution water hydrocyclone having a flow director disposed between a waste slurry inlet and a dilution water inlet. This flow director can direct the dilution water to establish a cyclone flow pattern before the dilution water contacts the waste slurry. This flow director can also limit the dilution water from flowing directly from the dilution water inlet to the waste slurry inlet, creating a spacing between the dilution water and the waste slurry from the waste slurry inlet, thereby reducing or preventing the reintroduction of solid fragments and / or contaminants into the upstream purifier.

[0008] According to one or more aspects of the present disclosure, a purification system for removing solid fragments and contaminants from a feed slurry may include a purifier that functions to separate the feed slurry into a received slurry and a waste slurry. This waste slurry may include at least a portion of the solid fragments and contaminants from the feed slurry. The purification system may further include a dilution device disposed downstream of the purifier and fluidly coupled to the waste outlet of the purifier. The dilution device may include a dilution water hydrocyclone. The dilution water hydrocyclone may include a dilution water inlet and a cyclone flow section downstream of the dilution water inlet. The cyclone flow section may have an upstream end and a downstream end. The dilution water hydrocyclone may further include an underflow outlet disposed at the downstream end of the cyclone flow section, a waste slurry inlet disposed at the top of the dilution water hydrocyclone and coupled to the waste slurry outlet of the purifier, and a flow guide disposed between the dilution water inlet and the waste slurry inlet. The flow guide may function to direct the flow of dilution water from the dilution water inlet axially at least toward the cyclone flow section.

[0009] According to one or more additional aspects, a method of removing solid fragments and contaminants from a feed slurry may include introducing the feed slurry into a purifier that functions to create a cyclone flow that separates the feed slurry into a waste slurry and a received slurry. The waste slurry may include at least a portion of the solid fragments and contaminants. The method may further include passing the waste slurry through a dilution water hydrocyclone fluidly coupled to a waste outlet of the purifier. The dilution water hydrocyclone may include a cyclone flow section, a dilution water inlet upstream of an upstream end of the cyclone flow section, a waste slurry inlet upstream of the upstream end of the cyclone flow section, an underflow outlet at a downstream end of the cyclone flow section, and a flow inducer disposed between the waste slurry inlet and the dilution water inlet. The method may further include introducing dilution water into the dilution water hydrocyclone through the dilution water inlet. By introducing the dilution water, the dilution water establishes a cyclone flow in an annular flow region defined between the flow inducer and an inner surface of the dilution water hydrocyclone. The method may further include contacting the dilution water with the waste slurry at an outlet end of the flow inducer. By contacting the dilution water with the waste slurry, at least a portion of the dilution water can mix with the waste slurry to reduce or prevent clogging of the purifier, the dilution device, or both.

[0010] It should be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed subject matter.

Brief Description of the Drawings

[0011] The accompanying drawings are included to provide a further understanding of the various embodiments and are incorporated herein and constitute a part hereof. The drawings illustrate the various embodiments described herein and, together with the description, serve to explain the principles and operation of the claimed subject matter.

Figure 1

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Mode for Carrying Out the Invention

[0012] Here, embodiments of the purification system according to the present disclosure will be referred to in detail. Whenever possible, the same reference numbers are used throughout the drawings and the detailed description to refer to the same or similar parts. Referring to FIG. 1, an embodiment of a purification system 100 for removing solid fragments and contaminants from a supply slurry 102 is schematically shown. The purification system 100 includes a purifier 110 that functions to separate the supply slurry 102 into a received slurry 122 and a waste slurry 124, and the waste slurry 124 includes at least a portion of the solid fragments and contaminants from the supply slurry 102. The purification system 100 further includes a dilution device 130 disposed downstream of the purifier 110 and fluidly coupled to the waste outlet 118 of the purifier 110. The dilution device 130 may include a dilution water hydrocyclone 132, and the dilution water hydrocyclone 132 may include a cyclone flow section 140 having a dilution water inlet 138 that is tangential to the dilution water hydrocyclone 132 and an upstream end adjacent to the dilution water inlet 138 and a downstream end downstream of the upstream end. The dilution water hydrocyclone 132 may further include an underflow outlet 142 disposed at the downstream end of the cyclone flow section 140, a waste slurry inlet 144 disposed at the upper portion 149 of the dilution water hydrocyclone 132 and coupled to the waste outlet 118 of the purifier 110, and a flow inducer 150 disposed between the dilution water inlet 138 and the waste slurry inlet 144. The flow inducer 150 can function to direct the flow of the dilution water 104 from the dilution water inlet 138 axially downwardly, at least toward the cyclone flow section 140.

[0013] Unless otherwise specified, none of the methods described herein are intended to require that the steps be performed in a particular order, nor are any particular orientations required for any of the devices. Accordingly, where a method claim does not actually recite the order that the steps should follow, or where an apparatus claim does not actually enumerate an order or orientation for individual components, or where it is not otherwise specifically stated in the claim or description that those steps should be limited to a particular order, or where no particular order or orientation for the components of an apparatus is recited, no order or orientation is ever intended to be implied in any way. This applies to any possible non-expression criteria for interpretation, including logical matters regarding the arrangement of steps, the flow of operations, the order of components, or the orientation of components; obvious meanings derived from grammatical construction or punctuation; and the number or type of embodiments described in the specification.

[0014] As used herein, terms indicating directions - such as up, down, right, left, front, back, top, bottom - are used only with respect to the drawn figures and the coordinate axes given thereto, and are not intended to imply absolute directions.

[0015] As used herein, nouns, unless otherwise specified, include plural referents. Therefore, for example, a reference to "a" component includes embodiments having two or more such components, unless the context clearly dictates otherwise.

[0016] As used herein, the terms "longitudinal" and "axial" may refer to a direction or orientation generally parallel to the central axis A of the dilution device 130, which may be parallel to the ±Z direction of the coordinate axes of the drawing.

[0017] As used herein, the term "radial" may refer to a direction along any radius extending outward from the central axis A of the dilution device 130.

[0018] As used herein, the term "angular" generally may refer to a direction of increasing or decreasing angle around the central axis A of the dilution device 130.

[0019] As used herein, the term "solid contaminant" or "solid fragment" is not intended to be in the incoming slurry and may refer to an undesirable solid object such as a piece of wood, a piece of metal, dried adhesive, sand, or other contaminant, and may be distinguished, for example, from solid components intended to be in a solid suspension such as fibers.

[0020] As used herein, the term "consistency" may refer to the solids content of a slurry and may be defined as the mass ratio of the mass of solids in the slurry to the total mass of the slurry.

[0021] As used herein, the terms "upstream" and "downstream" refer to the positioning of components or units of a purification system relative to the direction of flow of material through the purification system. For example, if material flowing through the purification system encounters a first component before it encounters a second component, the first component would be considered "upstream" of the second component. If the material encounters the second component before it encounters the first component, the first component would be considered "downstream" of the second component. For the dilution device 130, "upstream" and "downstream" are with respect to the axial flow of waste slurry through the dilution device 130 from the waste slurry inlet 144 to the underflow outlet 142.

[0022] Hydrocyclone purifiers have been used to remove solid fragments and contaminants from slurries. Specifically, hydrocyclone purifiers have been used to remove solid fragments and contaminants from fiber slurries in the paper pulp industry. The purification system disclosed herein is described in the context of removing solid fragments and / or contaminants from fiber slurries in paper pulp applications. However, it will be understood that the purification system of the present disclosure may be used in other industries including, but not limited to, food and beverage, textiles, oil and gas, chemical processing, construction, processed wood, plastics and rubber processing, or other industries.

[0023] A hydrocyclone purifier comprises a hydrocyclone and operates by generating a cyclone flow within the cylindrical or tapered portion of the hydrocyclone. This cyclone flow can generate a centrifugal force that moves the higher-density components, such as solid fragments or solid contaminants, radially outward towards the wall of the hydrocyclone, while the lower-density components are moved radially inward towards the center of the hydrocyclone. The hydrocyclone purifier may be a through-flow or reverse-flow hydrocyclone separator. In a through-flow hydrocyclone separator, the influent slurry may be introduced tangentially to the hydrocyclone at one end of the hydrocyclone separator, and both the higher-density waste stream and the received slurry stream exit from the opposite end of the hydrocyclone, with the higher-density waste stream flowing close to the wall of the hydrocyclone and the received slurry stream exiting from the center. The received slurry stream can be isolated from the higher-density waste stream by a tube, sometimes referred to as a vortex finder, inserted at the outlet of the hydrocyclone. An example of a through-flow hydrocyclone purifier can be found in U.S. Patent No. 5,769,243, the entire contents of which are hereby incorporated by reference.

[0024] A hydrocyclone purifier may comprise a reverse flow hydrocyclone, where the waste stream with a higher density is discharged from the underflow outlet of the hydrocyclone, and the receiving slurry with a lower density is discharged from the overflow outlet at the end of the hydrocyclone opposite to the underflow outlet. In a reverse flow hydrocyclone, the component with a higher density moves towards the wall and generally flows downward along the wall of the hydrocyclone. The component with a lower density is moved towards the center of the hydrocyclone and may flow in a reverse direction, generally upward, towards the overflow outlet. A further example of a reverse flow hydrocyclone purifier can be found in U.S. Patent No. 5,938,926, the entire contents of which are hereby incorporated by reference. Other types of slurry purifiers may be used to separate solid fragments and / or contaminants from the slurry.

[0025] Regardless of whether a through-flow hydrocyclone purifier, a reverse flow hydrocyclone purifier, or another type of purifier is used, the waste slurry with a higher density generated by the purifier may generally have a high concentration of solids. In some cases, the fiber viscosity and the concentration of solids in the waste stream may be high enough to cause clogging of the waste outlet or the piping or conduit downstream of the waste outlet. This clogging will limit the flow rate of the waste stream with a higher density flowing out of the purifier. Due to this flow rate limitation, solid fragments and contaminants from the waste slurry may be reintroduced into the receiving slurry, and this receiving slurry may carry this solid fragment and / or contaminant to the downstream process. Fragments and contaminants in the downstream process may cause problems such as nozzle clogging and other issues. If clogging of the waste outlet is confirmed, the hydrocyclone purifier must be removed from the production line and the waste outlet and the downstream conduits and pipes must be cleaned before restarting the operation of the purifier. This may reduce the productivity of the purification system.

[0026] Clogging can be reduced or prevented by adding dilution water to the waste slurry. The dilution water can be added to the waste slurry in one of two ways. In the first method, the dilution water may be axially and upwardly supplied into the waste outlet of the purifier through a dilution water pipe inserted into the waste slurry near the waste outlet of the purifier. The discharge end of the pipe is typically positioned somewhere in the area that starts just downstream of the waste outlet and ends just upstream of the waste outlet. Here, upstream and downstream are with respect to the axial direction of the flow of the waste slurry. The diluted waste slurry can be collected in a waste chamber in which the dilution pipe extends and is generally discharged radially or tangentially.

[0027] In the second method, the dilution water may be supplied into a cylindrical / conical dilution chamber immediately downstream from the waste outlet of the hydrocyclone of the purifier. In this method, the dilution water generally begins to mix with the waste slurry at the waste outlet. In both of these methods, the introduction of dilution water into the waste slurry poses a significant risk that the turbulence generated by the dilution mixing will disrupt some of the flow of the waste contaminants, carry them upward, and return them into the receiving slurry flow. The dilution water may contact the waste slurry before the cyclone flow of the dilution water can be established, thereby increasing both the non-circularity and substantially non-uniformity of the mixing process.

[0028] Accordingly, there is a need for a dilution device that functions to introduce dilution water into the waste stream from the hydrocyclone of the purifier without allowing the turbulent flow to carry solid fragments and contaminants and return them to the purifier and the receiving slurry. Referring to FIG. 1, a purification system 100 for removing solid fragments and contaminants from a supply slurry 102 according to the present disclosure is shown. The purification system 100 may include a purifier 110 and a dilution device 130 coupled to a waste outlet 118 of the purifier 110. The dilution device 130 may be a dilution water hydrocyclone 132 having a flow guide 150 that at least partially restricts the flow between a dilution water inlet 138 and a waste slurry inlet 144. The flow guide 150 of the dilution device 130 can establish a cyclone flow of the dilution water 104 within the dilution device 130 before the dilution water 104 mixes with the waste slurry 124. In the mixing zone, the axial component of the velocity of the cyclone flow of the dilution water 104 can act to carry the waste slurry 124 further downward into the cyclone flow section 140, thereby reducing or preventing solid fragments and / or contaminants from returning upward through the waste slurry inlet 144 into the purifier 110 due to the turbulent flow in the mixing zone.

[0029] Referring to FIG. 1, the purification system 100 may include a purifier 110. The purifier 110 may be a through-flow or reverse-flow hydrocyclone purifier. In one or more embodiments, the purifier 110 may be a reverse-flow hydrocyclone purifier. The purifier 110 may include a body 112, which may be an elongated hollow body. The body 112 may include a tapered section 120 extending over a substantial portion of the length L of the body 112. C In some embodiments, the tapered section 120 may be 50% or more, 60% or more, or even 70% or more of the axial length L of the length L of the body 112. C In some embodiments, the tapered section 120 may be the entire length L of the body 112. CT CIt may extend along. In one or more embodiments, the body 112 may include an inlet chamber 119 upstream of the tapered section 120. The inlet chamber 119 may be the part of the purifier 110 where the feed slurry 102 is first introduced through the slurry inlet 114. The inlet chamber 119 may be a cylindrical inlet chamber or a frustum-shaped inlet chamber.

[0030] The tapered section 120 may have a frustum-shaped configuration with a wide end and a narrow end, and this wide end has a larger diameter than the narrow end. The wide end may be disposed at the upstream end of the tapered section 120, and the narrow end may be disposed downstream of the wide end. The narrow end may be the downstream end of the tapered section 120. The wide end of the tapered section 120 may be coupled to the inlet chamber 119 and in fluid communication. The tapered section 120 may be defined by a cone angle α and an axial length L CT There may be. The tapered section 120 may have a length-to-diameter ratio sufficient to induce annular acceleration in the slurry flow as the feed slurry 102 descends through the purifier 110. The tapered section 120 may have a length-to-diameter ratio of 20:1 or more, or 23:1 or more. The tapered section 120 may have a cone angle α of less than 3°.

[0031] Referring again to FIG. 1, the body 112 of the purifier 110 may comprise a slurry inlet 114. The slurry inlet 114 may be coupled to the body 112 at the inlet chamber 119 or to the tapered section 120 proximate the wide end of the tapered section 120. The slurry inlet 114 may extend from the side of the body 112 and may be configured to introduce the feed slurry 102 into the purifier 110 in a manner that creates a cyclone flow within the purifier 110. In an embodiment, the slurry inlet 114 may be a tangential slurry inlet. In other words, the slurry inlet 114 may be tangential to the inner surface of the body 112. In one or more embodiments, the slurry inlet 114 may be coupled to the body 112 such that the slurry inlet 114 is substantially parallel to a plane that is tangential to the inner surface of the body 112. The term tangential is intended to include minor variations from the tangential direction, such as a plane that is at an angle of less than 10 degrees or less than 5 degrees from the tangential direction, or a plane that is parallel to the tangential direction but radially displaced from the tangential direction by less than 10% of the diameter of the slurry inlet 114. In an embodiment, the slurry inlet 114 may be oriented along a line that forms a non-zero angle with a plane that is tangential to the inner surface of the body 112, such as an angle greater than 0 degrees and less than 90 degrees.

[0032] The purifier 110 may include an overflow outlet 116 at the upper portion 117 of the purifier 110 and a waste outlet 118 at the narrow end of the tapered section 120. The overflow outlet 116 may include an open-ended conduit or pipe that extends at least partially into the purifier 110. This open-ended conduit may reduce or prevent the feed slurry 102 introduced into the purifier 110 from flowing directly into the overflow outlet 116 without being exposed to the cyclone flow within the purifier 110. The waste outlet 118 of the purifier 110 may be positioned at the narrow end of the tapered section 120. In one or more embodiments, the waste outlet 118 may have a cross-sectional area that is equal to or greater than the cross-sectional area of the overflow outlet 116.

[0033] Referring to FIG. 1, the purifier 110 can function to separate the supply slurry 102 into a received slurry 122 and a waste slurry 124. The supply slurry 102 may be introduced into the purifier 110 through the slurry inlet 114. Due to the orientation of the slurry inlet 114 with respect to the main body 112 of the purifier 110, the supply slurry 102 can flow along the inner surface of the main body 112 to form a cyclone flow pattern. In an embodiment, the slurry inlet 114 may be tangential to the main body 112 of the purifier 110, whereby the supply slurry 102 can be introduced tangentially to the purifier 110. The cross-sectional area of the purifier 110 decreases in the tapered section 120, whereby the supply slurry 102 accelerates annularly in a cyclone flow, creating a greater centrifugal force within the supply slurry 102. Due to the increased centrifugal force caused by the annular acceleration of the supply slurry 102 within the tapered section 120, the solid fragments and contaminants of the supply slurry 102 may move radially outward toward the inner surface of the main body 112. Without limitation, the received portion of the supply slurry 102, such as water or fibers, may move radially inward toward the central axis A of the purifier 110. The received portion of the supply slurry 102 may include water, fibers, diluents, and other components with a lower density than the solid fragments and contaminants.

[0034] The solid fragments and contaminants may move downward (i.e., in the -Z direction of the coordinate axes in FIG. 1) along the inner surface of the main body 112 in the tapered section 120 toward the waste outlet 118 in a primary vortex flow. The received slurry 122 may form a secondary vortex at the center of the purifier 110. This secondary vortex may create a flow of the received slurry 122 in a direction opposite to the primary vortex flow (i.e., in the +Z direction of the coordinate axes in FIG. 1). This secondary vortex may create a flow of the received slurry 122 toward the overflow outlet 116 of the purifier 110. The waste slurry 124 containing solid fragments and / or contaminants may exit the purifier 110 through the waste outlet 118. The received slurry 122 may exit the purifier 110 through the overflow outlet 116.

[0035] Referring back to FIG. 1, as previously described, the purification system 100 may further include a dilution device 130, which may be fluidly coupled to the waste outlet 118 of the purifier 110. The dilution device 130 may include a dilution water hydrocyclone 132 having a body 134 that defines an internal volume 136. The dilution water hydrocyclone 132 may further include a dilution water inlet 138, an inlet section 139, a cyclone flow section 140, an underflow outlet 142, a waste slurry inlet 144, and a flow inducer 150. Each of these features of the dilution device 130 will be further described herein. As shown in FIG. 1, the dilution device 130 may be coupled to the purifier 110 such that the waste slurry inlet 144 of the dilution device 130 is fluidly coupled to the waste outlet 118 of the purifier 110.

[0036] Referring to FIG. 2, the body 134 may have an inner surface 135 that defines the internal volume 136 of the dilution water hydrocyclone 132. The body 134 may be formed from a material that is resistant to wear by solid fragments or contaminants that have passed through the dilution device 130. Suitable materials for the body 134 may include, but are not limited to, ceramic materials, metals or metal alloys, or polymers / plastics, or other materials. In one or more embodiments, the body 134 may be a ceramic body. In an embodiment, the body 134 may be a plastic or polymer body.

[0037] Referring again to FIG. 2, the inlet section 139 may be disposed above the dilution device 130 proximate the dilution water inlet 138 and the waste slurry inlet 144. This inlet section 139 may be part of the dilution water hydrocyclone 132 where the flow of dilution water 104 changes from a substantially straight-line flow at the dilution water inlet 138 to a cyclone flow downstream of the dilution water inlet 138. The inlet section 139 may extend downwardly (i.e., in the -Z direction of the coordinate axes of FIG. 2) from the waste slurry inlet 144 toward the cyclone flow section 140. The inlet section 139 may be a cylindrical inlet section or a frustoconical inlet section. The inlet section 139 may be in fluid communication with the dilution water inlet 138. In one or more embodiments, the inlet section 139 may include an inlet passage 148 that is annular and slightly axially, an annular passage extending from the dilution water inlet 138 around the inlet section 139. The inlet passage 148 may be defined by a portion of the inner surface 135 of the body 134 that extends radially outward from the central axis A with respect to the inner surface 135 of the remaining portion of the inlet section 139. The inlet passage 148 may function to facilitate generating a cyclone flow pattern of the dilution water 104 within the inlet section 139 of the dilution water hydrocyclone 132.

[0038] Referring to FIGS. 1 and 2, the dilution water inlet 138 may be in fluid communication with the inlet section 139 and may be disposed on the side of the main body 134 in the inlet section 139. The dilution water inlet 138 may be configured to introduce the dilution water 104 into the dilution device 130 in such a manner that the dilution water 104 flows around the inner surface 135 of the main body 134 to generate a cyclone flow within the dilution device 130. The dilution water inlet 138 may be tangential to the main body 134 of the dilution water hydrocyclone 132, may be radial with respect to the main body 134 of the dilution water hydrocyclone 132, or may be disposed at a horizontal angle greater than 0 degrees and less than 90 degrees with respect to a radial straight line extending radially outward from the central axis A of the dilution water hydrocyclone 132. In an embodiment, the dilution water inlet 138 may be directed tangentially to the inner surface 135 of the main body 134 in the inlet section 139. The dilution water inlet 138 may be a tangential inlet. In an embodiment, the dilution water inlet 138 may be coupled to or incorporated into the main body 134 such that the dilution water inlet 138 is substantially parallel to a plane that is tangential to the inner surface of the main body 134 in the inlet section 139. The term tangential direction is intended to include slight variations from the tangential direction, such as a plane that is at an angle of less than 10 degrees or less than 5 degrees from the tangential direction, or a plane that is parallel to the tangential direction but is displaced radially from the tangential direction by less than 10% of the diameter of the dilution water inlet 138. In an embodiment, the dilution water inlet 138 may be directed to introduce the dilution water 104 radially inward into the inlet section 139. In an embodiment, the dilution water inlet 138 may be directed at an angle between the radial direction and the tangential direction. The dilution water inlet 138 may be fluidly coupled to a source (not shown) of the dilution water 104. The dilution water inlet 138 may be substantially perpendicular to the vertical direction (i.e., the ±Z axis of the coordinate axes in FIG. 2) or may be slightly angled in the axial direction (i.e., may form an angle with a plane perpendicular to the ±Z axis in FIG. 2). With respect to the orientation of the dilution water inlet 138, "slightly angled" may refer to an angle of less than 5 degrees, and further less than 3 degrees, between the center line of the dilution water inlet 138 and a plane perpendicular to the Z axis in FIG. 2.The dilution water inlet 138 may be positioned to create a cyclone flow of the dilution water 104 that is clockwise or counterclockwise. In other words, the dilution water inlet 138 may be positioned such that the angular component of the cyclone flow is clockwise or counterclockwise for the dilution water 104 in the inlet section 139. In an embodiment, the cyclone flow of the dilution water 104 may have an angular direction opposite to the angular direction of the cyclone flow of the waste slurry 124.

[0039] Referring to FIGS. 1 and 2, the waste slurry inlet 144 may be disposed in the upper portion 149 of the main body 134. The waste slurry inlet 144 may be axially directed and may be centered about the central axis A of the dilution device 130 and / or the purifier 110. As described above, the waste slurry inlet 144 may be fluidly coupled to the waste outlet 118 of the purifier 110. The waste slurry inlet 144 may function to receive the waste slurry 124 from the waste outlet 118 of the purifier 110 and pass the waste slurry 124 axially downward (i.e., in the -Z direction of the coordinate axes in FIG. 2) into the inlet section 139 of the dilution device 130. The waste slurry inlet 144 may be large enough to flow the waste slurry 124 downward along the side wall of the purifier 110 to the dilution device 130 while flowing the backflow of the air core and / or the receiving slurry 122 upward (i.e., in the +Z direction) at the center of the waste slurry inlet 144 and back to the purifier 110.

[0040] Referring again to FIG. 2, the cyclone flow section 140 may extend from the inlet section 139 in a downward direction (i.e., in the -Z direction of the coordinate axes in FIG. 2) toward the underflow outlet 142. The cyclone flow section 140 may be cylindrical or tapered and may have an upstream end and a downstream end. As shown in FIG. 2, in the embodiment, the cyclone flow section 140 may be tapered, such as having a frustoconical shape with an inner dimension (e.g., diameter) at the upstream end that is larger than the inner dimension (e.g., diameter) at the downstream end. In other embodiments, the cyclone flow section 140 may be cylindrical with both the upstream end and the downstream end having similar or equal inner dimensions. The upstream end of the cyclone flow section 140 may be oriented close to the inlet section 139, and the downstream end may terminate at the underflow outlet 142. The dilution device 130 may have an overall length L D which may be the distance from the waste slurry inlet 144 to the underflow outlet 142. The cyclone flow section 140 may have a length L DT which may be the distance between the upstream end and the downstream end of the cyclone flow section 140. The length L DT of the cyclone flow section 140 may be 60% or more, or even 70% or more, etc., of the overall length L D of the dilution device 130, or may be 50% or more of the overall length L D of the dilution device 130. When the cyclone flow section 140 is tapered, the cyclone flow section 140 may have a taper angle β defined as the angle between the inner surface 135 of the main body 134 in the cyclone flow section 140 and a plane perpendicular to the central axis A. The cyclone flow section 140 of the dilution device 130 may have a taper angle β of more than 0 degrees and 7 degrees or less, or more than 0 degrees and 5 degrees or less, etc., of 0 (zero) degrees or more and 10 degrees or less.

[0041] Referring to FIG. 2, the dilution device 130 includes an underflow outlet 142 disposed at the downstream end of the cyclone flow section 140. The underflow outlet 142 can function to allow the diluted waste slurry 170 to flow out of the cyclone flow section 140 of the dilution device 130. The underflow outlet 142 may be centered on the central axis A of the dilution device 130 and may be substantially on the axis. In some embodiments, the underflow outlet 142 may be fluidly coupled to a discharge conduit 143, which may extend radially outward (i.e., in the +X direction of the coordinate axes in FIG. 2) and downward from the underflow outlet 142 (i.e., in the -Z direction). The discharge conduit 143 can function to discharge the diluted waste slurry 170 from the dilution device 130 and pass it to one or more downstream processes for further treatment of the diluted waste slurry 170.

[0042] Referring again to FIGS. 2 and 3, as described above, the dilution device 130 may include a flow guide 150 disposed within the inlet section 139 of the dilution device 130. The flow guide 150 may be a hollow tube. The flow guide 150 may be made from a flow guide wall 154 that is a continuous wall forming the hollow tube. The flow guide 150 may have an inlet end 156 and an outlet end 158. The inlet end 156 may be coupled to the body 134 proximate the waste slurry inlet 144 and may be in fluid communication with the waste slurry inlet 144. The inlet end 156 may be an open end through which the waste slurry 124 is passed into the flow guide 150. The flow guide wall 154 may surround the waste slurry inlet 144 at the inlet end 156 of the flow guide 150 such that the waste slurry 124 flowing into the dilution device 130 through the waste slurry inlet 144 flows into the flow guide 150 (i.e., into the elongated hollow space defined by the inner surface 162 of the flow guide wall 154). The outlet end 158 may be disposed at the end of the flow guide 150 opposite the inlet end 156 and may be disposed vertically downward (i.e., in the -Z direction) downstream of the inlet end 156. The outlet end 158 of the flow guide 150 may be an open end such that the waste slurry 124 passing through the flow guide 150 can flow into the inlet section 139 and the cyclone flow section 140 of the dilution device 130. The inlet end 156 and the outlet end 158 may have any cross-sectional shape, such as circular, polygonal, elliptical, or irregular. In one or more embodiments, the inlet end 156 and the outlet end 158 may have a circular cross-sectional shape.

[0043] The flow guide wall 154 may be cylindrical or frustoconical. The flow guide wall 154 may extend downward (i.e., in the -Z direction of the coordinate axes of FIG. 2) from the upper portion 149 of the body 134 into the inlet section 139. Referring to FIG. 4, the flow guide wall 154 may have an axial length L FD which is the distance between the inlet end 156 and the outlet end 158 of the flow guide 150. The axial length L of the flow guide wall 154 FDThe axial length L of the flow director wall 154 may be sufficient to establish a cyclonic flow pattern before the dilution water 104 mixes with the waste slurry 124 passing through the flow director 150. FD is the axial length L of the inlet section 139 DI where the axial length L of the inlet section 139 may be 50% or more of DI is the distance between the top 149 of the inlet section 139 and the upstream end of the cyclone flow section 140. The axial length L of the flow director wall 154 FD is the axial length L of the inlet section 139 DI It may be 60% or more, 70% or more, 80% or more, or even 90% or more of the total.

[0044] The outlet end 158 of the flow director 150 may have an axial surface 160 that faces generally downward (i.e., in the −Z direction of the coordinate axes of FIG. 2 ) toward the cyclone flow section 140. The axial surface of the outlet end 158 may be a generally planar flat surface. The flat axial surface 160 may provide increased turbulence at the outlet end 158 of the flow director 150 as compared to a rounded or tapered axial surface 160. This increased turbulence at the outlet end 158 may help mix the dilution water 104 with the waste slurry as the two streams mix at the outlet end 158 of the flow director 150.

[0045] 2 and 3, the inner surface 162 of the flow director 150 may include one or more anti-rotation tabs 163 extending inwardly from the inner surface 162 of the flow director 150. The anti-rotation tabs 163 may extend inwardly from the inner surface 162 of the flow director 150. FD The anti-rotation tabs 163 may be rectangular in shape with a long dimension parallel to the central axis A so as to extend axially (i.e., in the ±Z direction of the coordinate axes in FIG. 2) along the axis A. The anti-rotation tabs may be spaced annularly. In one or more embodiments, the anti-rotation tabs 163 may be spaced every 90 degrees.

[0046] In one or more embodiments, the flow guide 150 may include a plurality of openings (not shown) in the flow guide wall 154, such that at least a small amount of the dilution water 104 may pass through the hollow tube and mix with the waste slurry 124 upstream of the outlet end 158 of the flow guide 150. In an embodiment, the openings may be positioned proximate to the outlet end 158 of the flow guide 150.

[0047] Referring to FIG. 4, the inner surface 162 of the flow guide 150 may define a central flow region 164 through which the waste slurry 124 from the purifier 110 passes from the waste slurry inlet 144 into the dilution water hydrocyclone 132. The outer surface of the flow guide wall 154 and the inner surface 135 (FIG. 2) of the body 134 of the dilution water hydrocyclone 132 may define an annular flow region 166 therebetween. The annular flow region 166 may be in fluid communication with the dilution water inlet 138. The annular flow region 166 may include an inlet passage 148 if present. The annular flow region 166 may extend from the inlet end 156 to the outlet end 158 of the flow guide 150. The annular flow region 166 may be in fluid communication with the cyclone flow section 140 of the dilution water hydrocyclone 132 at the outlet end of the flow guide 150.

[0048] The flow guide 150 may function to at least partially or completely restrict a direct flow of the dilution water 104 between the dilution water inlet 138 and the waste slurry inlet 144. By at least partially or completely restricting the dilution water 104 from flowing directly from the dilution water inlet 138 to the waste slurry inlet 144, a cyclone flow of the dilution water 104 may be established within the inlet section 139 of the dilution device 130 before the dilution water 104 contacts the waste slurry 124 at the outlet end 158 of the flow guide 150. As further described herein, restricting the flow of the dilution water 104 within the inlet section 139 may reduce or prevent the reintroduction of solid fragments and / or contaminants back into the purifier 110, and / or the re-entrainment of solid fragments and contaminants from the waste slurry 124 back into the receiving slurry 122.

[0049] Referring now to FIGS. 1 and 4, in the operation of the purification system 100, the purifier 110 may function to separate the supply slurry 102 into a received slurry 122 (FIG. 1) and a waste slurry 124. When the purifier 110 is a hydrocyclone purifier, the waste slurry 124 flowing out from the waste outlet 118 of the purifier 110 may have a cyclone flow pattern. The waste slurry 124 may be passed from the waste outlet 118 of the purifier 110, through the waste slurry inlet 144, and into the central flow region 164 of the flow guide 150. The waste slurry 124 may flow through the flow guide 150 in a cyclone flow to the outlet end 158 of the flow guide 150. The cyclone flow of the waste slurry 124 may have an annular component and an axial component. The annular component of the cyclone flow of the waste slurry 124 may be clockwise (i.e., the +θ direction of the cylindrical coordinate axis in FIG. 4) or counterclockwise (i.e., the -θ direction of the cylindrical coordinate axis in FIG. 4), depending on the structure of the purifier 110. The axial component of the cyclone flow of the waste slurry 124 in the flow guide 150 may generally be downward (i.e., the -Z direction of the cylindrical coordinate axis in FIG. 4). The cyclone flow of the waste slurry 124 passing through the central flow region 164 may be characterized by an axial flow velocity V R at the outlet end 158 of the flow guide 150.

[0050] The flow through the flow guide 150 may further include a core flow 168 in which the fluid flows in a reverse cyclone flow upward (i.e., in the +Z direction of the cylindrical coordinate axis in FIG. 4) through the dilution device 130 and the purifier 110. The core flow 168 may be disposed at the center of the dilution device 130, such as along the central axis A of the dilution device 130. In one or more embodiments, the core flow 168 may enter from the underflow outlet 142 and include air or other gas that passes upward through the dilution device 130. Alternatively, or in addition, the core flow 168 may include the less dense fluid, which may include the less dense components from the dilution device 130, such as any receiving fibers or other receiving components of water and slurry.

[0051] Referring again to FIG. 4, dilution water 104 may be introduced into the dilution device 130 through the dilution water inlet 138. The flow rate of the dilution water 104 may be sufficient to dilute the waste slurry 124 in order to reduce clogging of the dilution water hydrocyclone 132, particularly clogging of the cyclone flow section 140 and / or the underflow outlet 142 of the dilution water hydrocyclone 132. The volumetric flow rate of the dilution water 104 may be sufficient to reduce the viscosity of the waste slurry 124, which may have an initial viscosity of solids up to 6%. The ratio of the volumetric flow rate of the dilution water 104 to the volumetric flow rate of the waste slurry 124 flowing into the dilution water hydrocyclone 132 may be from 0.45:1 to 1.55:1, from 0.75:1 to 1.25:1, or about 1:1. In one or more embodiments, the ratio of the volumetric flow rate of the dilution water 104 to the volumetric flow rate of the waste slurry 124 may be about 1:1.

[0052] The dilution water 104 may flow from the dilution water inlet 138 through the annular flow region 166 in an angular and axially downward direction (i.e., in the -Z direction of the coordinate axes in FIG. 2) to the outlet end 158 of the flow inducer 150. If the inlet section 139 of the dilution device 130 comprises an inlet passage 148, the dilution water 104 may be directed by the inlet passage 148 to form a cyclone flow pattern within the annular flow region 166. The angular component of the cyclone flow of the dilution water 104 through the annular flow region 166 may be clockwise or counterclockwise. The angular component of the flow direction of the dilution water 104 through the annular flow region 166 may be co-flow or counter-flow with respect to the angular direction of the cyclone flow of the waste slurry 124 through the central flow region 164. In an embodiment, the angular component of the cyclone flow of the dilution water 104 within the annular flow region 166 may be in an angular direction opposite to the angular direction of the cyclone flow of the waste slurry 124 in the central flow region 164. The axial component of the cyclone flow of the dilution water 104 in the annular flow region 166 may be axially downward (i.e., in the -Z direction of the coordinate axes in FIG. 4). The axial component of the cyclone flow of the dilution water 104 through the annular flow region 166 is the axial velocity V at the outlet end 158 of the flow inducer 150 DWmay be characterized by.

[0053] The cyclone flow of the waste slurry 124 and the cyclone flow of the dilution water 104 can contact each other at the outlet end 158 of the flow inducer 150. When the flow of the dilution water 104 contacts the flow of the waste slurry 124, mixing occurs between the dilution water 104 and the waste slurry 124. The mixing between the dilution water 104 and the waste slurry 124 may occur in a mixing zone 180 proximate to the outlet end 158 of the flow inducer 150. When the dilution water 104 and the waste slurry 124 are mixed in the mixing zone 180, a diluted waste slurry 170 is produced, which will continue to be a cyclone flow downward (i.e., in the -Z direction) through the cyclone flow section 140 of the dilution water hydrocyclone 132.

[0054] The mixing zone 180 may be spaced from the waste slurry inlet 144 by a distance due to the presence of the flow inducer 150. That distance will be equal to the length L of the flow inducer 150. By spacing the mixing zone 180 from the waste slurry inlet 144 by a length L, the flow inducer 150 can establish a cyclone flow of the dilution water 104 before contacting the dilution water 104 with the waste slurry 124 within the mixing zone 180. The established cyclone flow of the dilution water 104 will have a greater velocity component of the dilution water 104 in the -Z direction compared to introducing the dilution water 104 into the dilution device 130 without the flow inducer 150. This greater downward (-Z direction) axial velocity component of the dilution water reduces or prevents some of the dilution water 104 from carrying some of the solid fragments and / or contaminants back through the waste slurry inlet 144 or into the core flow 168 by the flow turbulence and turbulent mixing within the mixing zone 180. Without intending to be bound by any particular theory, the velocity (V) of the dilution water 104 FD will be equal. By spacing the mixing zone 180 from the waste slurry inlet 144 by a length L FD only, the flow inducer 150 can establish a cyclone flow of the dilution water 104 before contacting the dilution water 104 with the waste slurry 124 within the mixing zone 180. The established cyclone flow of the dilution water 104 will have a greater velocity component of the dilution water 104 in the -Z direction compared to introducing the dilution water 104 into the dilution device 130 without the flow inducer 150. This greater downward (-Z direction) axial velocity component of the dilution water reduces or prevents some of the dilution water 104 from carrying some of the solid fragments and / or contaminants back through the waste slurry inlet 144 or into the core flow 168 by the flow turbulence and turbulent mixing within the mixing zone 180. Without intending to be bound by any particular theory, the velocity (V) of the dilution water 104 DIt is considered that the dilution water 104 will further convey the waste slurry 124 in the downward -Z direction (away from downstream of the waste slurry inlet 144) by the axial component below (). Therefore, the flow inducer 150 can improve the separation efficiency of the purification system 100.

[0055] Length L FD If it is too small, the mixing zone 180 will be too close to the waste slurry inlet 144, and the axial component of the velocity of the dilution water 104 in the downward direction (-Z direction) will not be sufficient to continuously convey the waste slurry 124 downstream to the cyclone flow section 140. As a result, turbulent mixing occurs, and the dilution water 104 may carry at least a part of the solid fragments and / or contaminants from the waste slurry 124 back into the waste slurry inlet 144. The possibility of reintroducing the solids from the waste slurry 124 back into the purifier 110 depends on the length L of the flow inducer 150 FD decreases as it increases. Therefore, by increasing the length L of the flow inducer 150, the separation efficiency of the purification system 100 can be improved by reducing the reintroduction of solid fragments and contaminants into the receiving slurry. However, if the length L FD is too large, the dilution water 104 will not be effective in reducing or preventing the clogging of the flow inducer 150 by the waste slurry 124. This may occur when the flow inducer 150 is overly long. In one or more embodiments, the length L FD may be smaller than the length L of the inlet section 139 of the dilution water hydrocyclone 132 FD Referencing FIG. 4 again, as described above, the waste slurry 124 may enter the mixing zone 180 at the outlet end 158 of the flow inducer 150 with an axial velocity V DI (that is, the axial component of the velocity in the -Z direction of the cylindrical coordinate axis in FIG. 4). The dilution water 104 may enter the mixing zone 180 at the outlet end 158 of the flow inducer 150 with an axial velocity V

[0056] R D D R D D / V RThe ratio may be sufficient for the dilution water 104 to continuously convey the waste slurry 124 downward (i.e., in the -Z direction of the coordinate axis in FIG. 4) into the cyclone flow section 140. The ratio V D / V R may be 0.25 or more, and further may be 0.4 or more. V D / V R may be 0.75 or less, and further may be 0.6 or less. V D / V R The ratio may be from 0.25 to 0.75, or from 0.4 to 0.6, or about 0.5. In some embodiments, V D may be half of V R . If the velocity V D of the dilution water 104 is too large, the dilution water 104 may create too large a turbulent flow within the mixing zone 180, which may increase the re-entrainment back into the receiving slurry 122 of solid fragments and / or contaminants. If the velocity V D of the dilution water 104 is too small, the dilution water 104 may not provide sufficient mixing with the waste slurry 124 to prevent clogging of the dilution water hydrocyclone 132.

[0057] Referring to FIG. 5, a dilution device 230 without a flow guide 150 is schematically shown. All other features of the dilution device 230 are the same as those of the dilution device 130 in FIG. 4, except for the absence of the flow guide 150. Referring to FIG. 5, when there is no flow guide 150 in the inlet section 139 of the dilution device 230, the dilution water 104 entering the inlet section 139 from the dilution water inlet 138 immediately contacts the waste slurry 124 entering the inlet section 139 through the waste slurry inlet 144. Thereby, a mixing zone 180 is created that is located directly adjacent to the waste slurry inlet 144. As shown in FIG. 5, without the flow guide 150, the mixing zone 180 is not spaced from the waste slurry inlet 144. The incoming dilution water 104 has a velocity vector generally in the horizontal direction (i.e., perpendicular to the ±Z directions of the axis A and the cylindrical coordinate axis in FIG. 5) at the dilution water inlet 138. The incoming dilution water 104 has little or no velocity component / vector in the ±Z direction when first entering the inlet section 139. Therefore, when the dilution water 104 contacts the waste slurry 124 in the mixing zone 180, the dilution water 104 does not have a sufficient -Z direction velocity to contribute to transporting the waste slurry 124 further downstream into the cyclone flow section 140. Without a -Z direction velocity component in the dilution water 104, due to turbulent mixing in the mixing zone 180, at least some of the dilution water 104 and solid fragments and / or contaminants may flow back into the purifier 110 through the waste slurry inlet 144, where the solid fragments and / or contaminants may, according to the case, enter the backflow of the received slurry 122. Thereby, compared with the dilution device 130 in FIG. 4, the separation efficiency of the purification system 100 may be reduced.

[0058] Referring now to FIG. 6, for the purification system 100 (reference number 600) with the dilution device 130 of FIG. 4 and the purification system 100 (reference number 602) with the dilution device 230 of FIG. 5, the separation efficiency (Y-axis), as a function of the relative pressure (X-axis), regarding the removal of sand particles from the fiber slurry, is shown in a graph. As shown in FIG. 6, the dilution device 130 of FIG. 4 (reference number 600) having the flow inducer 150 has a greater separation efficiency for removing sand particles from the fiber slurry compared to the dilution device 230 of FIG. 5 that does not have the flow inducer 150. The flow inducer 150 can increase the efficiency by reducing the re-entrainment of solid debris and / or contaminants and the passage back to the purifier 110 of the solid debris and / or contaminants. Referring again to FIG. 4, in addition, when the flow inducer 150 is present, the liquid centrifugation of the lighter incoming fibers from the waste slurry 124 will be further improved. In the cyclone flow section 140, these lighter incoming fibers may move towards the central axis A of the dilution water hydrocyclone 132 and mix with the core flow 168 and may flow back into the incoming slurry 122. Thereby, the yield of the incoming slurry 122 from the purification system 100 increases, and the efficiency can be further improved.

[0059] Referring now to FIG. 7, in one or more embodiments, the purification system 100 may be incorporated into a purification system assembly 300 that includes a plurality of purification systems 100 operating in parallel. The purification system assembly 300 may include a plurality of purifiers 110 and a plurality of dilution devices 130, where each of the dilution devices 130 is fluidly connected to one of the waste outlets 118 within the purifier 110.

[0060] Referring to FIGS. 1 and 2, a method of removing solid fragments and contaminants from a supply slurry 102 may include introducing the supply slurry 102 into a purifier 110 that functions to create a cyclone flow that separates the supply slurry 102 into a waste slurry 124 and a received slurry 122. The waste slurry 124 may include at least a portion of the solid fragments and contaminants from the supply slurry 102. The purifier 110 may have any of the features described hereinabove for the purifier 110. The method may further include passing the waste slurry 124 through a dilution water hydrocyclone 132 fluidly connected to a waste outlet 118 of the purifier 110. The dilution water hydrocyclone 132 may have any of the features of the dilution water hydrocyclone 132 described hereinabove. For example, the dilution water hydrocyclone 132 may include a cyclone flow section 140, a dilution water inlet 138 disposed upstream of an upstream end of the cyclone flow section 140, a waste slurry inlet 144 disposed upstream of the upstream end of the cyclone flow section 140, an underflow outlet 142 at a downstream end of the cyclone flow section 140, and a flow inducer 150 disposed between the waste slurry inlet 144 and the dilution water inlet 138. The method may further include introducing dilution water 104 into the dilution water hydrocyclone 132 through the dilution water inlet 138. The dilution water inlet 138 may be positioned to introduce the dilution water 104 into a side of the dilution water hydrocyclone 132. When the dilution water is introduced, the dilution water 104 can establish a cyclone flow within an annular flow region 166 defined between the flow inducer 150 and an inner surface 135 of a body 134 of the dilution water hydrocyclone 132. The method may further include contacting the dilution water 104 with the waste slurry 124 at an outlet end 158 of the flow inducer 150. When the dilution water 104 is contacted with the waste slurry 124, at least a portion of the dilution water 104 can mix with the waste slurry 124 to reduce or prevent clogging of the purifier 110, the dilution device 130, or both.

[0061] In an embodiment, the method may further include a step of recovering the receiving slurry 122 from the overflow outlet 116 of the purifier 110. The step of recovering the receiving slurry 122 may include a step of discharging the receiving slurry 122 from the overflow outlet 116 of the purifier 110. In an embodiment, the method may further include a step of recovering the diluted waste slurry 170 from the underflow outlet 142 of the dilution water hydrocyclone 132. The step of recovering the diluted waste slurry 170 may include discharging the diluted waste slurry 170 from the underflow outlet 142 and, if necessary, discharging it from a discharge conduit 143 fluidly connected to the underflow outlet 142.

[0062] In an embodiment, the method may include a step of introducing the dilution water 104 into the dilution water hydrocyclone 132 in a direction that generates a cyclone flow of the dilution water 104 having an angular direction opposite to the angular direction of the cyclone flow of the waste slurry 124. In an embodiment, the method may include a step of introducing the dilution water 104 into the dilution water hydrocyclone 132 substantially horizontally. The step of introducing the dilution water 104 horizontally into the dilution water hydrocyclone 132 may include introducing the dilution water 104 tangentially, radially, or at a horizontal angle between 0 degrees and 90 degrees with respect to a radial straight line extending radially outward from the central axis A. In an embodiment, the method may include a step of introducing the dilution water 104 into the dilution water hydrocyclone 132 tangentially. In an embodiment, the method may include a step of introducing the dilution water 104 at an angle with respect to a tangential plane with respect to the body of the dilution water hydrocyclone 132. The waste slurry may have a solids consistency of 6% or less. In an embodiment, the ratio of the flow rate of the dilution water 104 introduced into the dilution water hydrocyclone 132 to the flow rate of the waste slurry 124 introduced into the dilution water hydrocyclone 132 may be 0.45:1 to 0.55:1, 0.75:1 to 1.25:1, or about 1:1. In an embodiment, the method may include an axial velocity V D of the dilution water 104 having an axial velocity V Rmay include a step of mixing with the waste slurry 124 having V R V divided by D has a ratio from 0.25 to 0.75.

[0063] In an embodiment, the supply slurry 102 may include a fiber slurry. In an embodiment, the supply slurry 102 may be a fiber slurry, and the method may include a step of passing the receiving slurry through a papermaking process. In an embodiment, the purifier 110 may be a countercurrent hydrocyclone purifier. This method may further include a step of restricting the flow between the dilution water inlet 138 and the waste slurry inlet 144. Restricting the flow can reduce the flow returning into the purifier 110 of solid fragments and / or contaminants.

[0064] A first aspect of the present disclosure may relate to a purification system for removing solid fragments and contaminants from a supply slurry. The purification system may include a purifier configured to separate the supply slurry into a receiving slurry and a waste slurry, the waste slurry including at least a portion of the solid fragments and contaminants from the supply slurry. The purification system may also include a dilution device disposed downstream of the purifier and fluidly coupled to the waste outlet of the purifier. The dilution device may include a dilution water hydrocyclone having a dilution water inlet, a cyclone flow section downstream of the dilution water inlet and having an upstream end and a downstream end, an underflow outlet disposed at the downstream end of the cyclone flow section, a waste slurry inlet disposed at the top of the dilution water hydrocyclone and coupled to the waste slurry outlet of the purifier, and a flow inducer disposed between the dilution water inlet and the waste slurry inlet. The flow inducer may be configured to direct the flow of dilution water from the dilution water inlet axially at least toward the cyclone flow section.

[0065] A second aspect of the present disclosure may include the first aspect where the flow inducer may be disposed radially between the dilution water inlet and the waste slurry inlet.

[0066] A third aspect of the present disclosure may include either the first or second aspect, wherein the flow guide may at least somewhat restrict the flow of dilution water from the axially oriented dilution water inlet toward the waste slurry inlet.

[0067] A fourth aspect of the present disclosure may include any one of the first to third aspects, wherein the flow guide may be made of a hollow tube having an inlet end and an outlet end coupled to the dilution water hydrocyclone in proximity to the waste slurry inlet, and the hollow tube may extend axially from the waste slurry inlet toward the cyclone flow compartment.

[0068] A fifth aspect of the present disclosure may include the fourth aspect, wherein the inlet end of the hollow tube may surround the waste slurry inlet.

[0069] A sixth aspect of the present disclosure may include either the fourth or fifth aspect, wherein the outlet end of the flow guide may be disposed within the inlet compartment of the dilution water hydrocyclone.

[0070] A seventh aspect of the present disclosure may include any one of the fourth to sixth aspects, wherein the flow guide may be a cylindrical hollow tube.

[0071] An eighth aspect of the present disclosure may include any one of the fourth to sixth aspects, wherein the flow guide may be a frustum-shaped hollow tube.

[0072] A ninth aspect of the present disclosure may include any one of the fourth to eighth aspects, wherein the outlet end of the flow guide may have an inner diameter dimension that is larger than the inner diameter dimension of the inlet end of the flow guide.

[0073] A tenth aspect of the present disclosure may include any one of the first to ninth aspects, wherein the outlet end of the flow guide may have a flat axial surface.

[0074] A 11th aspect of the present disclosure may include any one of the 1st to 10th aspects, where the flow guide may include a plurality of openings extending through the flow guide from the outer surface of the flow guide to the inner surface of the flow guide.

[0075] A 12th aspect of the present disclosure may include any one of the 1st to 11th aspects, where the flow guide may be provided with one or more anti-rotation tabs coupled to the inner surface of the hollow tube.

[0076] A 13th aspect of the present disclosure may include any one of the 1st to 12th aspects, where the cyclone flow section may be made from a cylindrical section.

[0077] A 14th aspect of the present disclosure may include any one of the 1st to 13th aspects, where the cyclone flow section may be a tapered section having a frustoconical shape, and the downstream end may have an inner diameter dimension smaller than the inner diameter dimension of the upstream end.

[0078] A 15th aspect of the present disclosure may include any one of the 1st to 14th aspects, where the dilution water hydrocyclone may include an inlet section defined between the waste slurry inlet and the cyclone flow section, and the flow guide may have an axial length of 50% or more of the axial length of the inlet section.

[0079] A 16th aspect of the present disclosure may include any one of the 1st to 15th aspects, where the flow guide and the body of the dilution water hydrocyclone may define an annular flow region disposed between the flow guide and the body, and the dilution water inlet may be in fluid communication with the annular flow region.

[0080] A 17th aspect of the present disclosure may include any one of the 1st to 16th aspects, where the dilution water hydrocyclone may include an inlet section axially disposed between the cyclone flow section and the waste slurry inlet.

[0081] The 18th aspect of the present disclosure may include any one of the 1st to 17th aspects, in which the center line of the flow guide may coincide with the central axis of the dilution water hydrocyclone.

[0082] The 19th aspect of the present disclosure may include any one of the 1st to 18th aspects, in which the dilution water inlet is disposed on the side of the dilution water hydrocyclone. The dilution water inlet may be tangential to the main body of the dilution water hydrocyclone, may be radial to the main body of the dilution water hydrocyclone, or may be disposed at a horizontal angle greater than 0 degrees and less than 90 degrees with respect to a radial straight line extending radially outward from the central axis of the dilution water hydrocyclone.

[0083] The 20th aspect of the present disclosure may include any one of the 1st to 19th aspects, in which the purifier may include a reverse flow hydrocyclone purifier.

[0084] The 21st aspect of the present disclosure includes a hydrocyclone purifier in which the purifier includes a slurry inlet, a tapered section, an overflow outlet close to the wide end of the tapered section, and a waste outlet downstream of the narrow end of the tapered section. This hydrocyclone purifier functions to generate a cyclone flow that separates the supplied slurry into waste slurry at the waste outlet and received slurry at the overflow outlet. The waste slurry may include solid fragments, contaminants, or both.

[0085] The 22nd aspect of the present disclosure may relate to a purification system assembly that may include a plurality of purification systems according to any one of the 1st to 21st aspects, and the plurality of purification systems may be operated in parallel.

[0086] The 23rd aspect of the present disclosure may include the 22nd aspect, in which a plurality of purification systems may include a plurality of purifiers and a plurality of dilution devices, and each of the dilution devices is coupled to one of the waste outlets within the purifier.

[0087] A 24th aspect of the present disclosure may relate to a method of removing solid fragments and contaminants from a feed slurry. The method may include introducing the feed slurry into a purifier that functions to create a cyclone flow that separates the feed slurry into a waste slurry and a received slurry, where the waste slurry may include at least a portion of the solid fragments and contaminants. The method may further include passing the waste slurry through a dilution water hydrocyclone fluidly coupled to a waste outlet of the purifier. The dilution water hydrocyclone may include a cyclone flow section, a dilution water inlet upstream of an upstream end of the cyclone flow section, a waste slurry inlet upstream of the upstream end of the cyclone flow section, an underflow outlet at a downstream end of the cyclone flow section, and a flow inducer disposed between the waste slurry inlet and the dilution water inlet. The method may further include introducing dilution water into the dilution water hydrocyclone through the dilution water inlet. By introducing the dilution water into the dilution water hydrocyclone, the dilution water can establish a cyclone flow in an annular flow region defined between the flow inducer and an inner surface of the dilution water hydrocyclone. The method may further include contacting the dilution water with the waste slurry at an outlet end of the flow inducer. By contacting the dilution water with the waste slurry, at least a portion of the dilution water can mix with the waste slurry to reduce or prevent clogging of the purifier, the dilution device, or both.

[0088] A 25th aspect of the present disclosure may include the 24th aspect, further including the step of recovering the received slurry from an overflow outlet of the purifier.

[0089] A 26th aspect of the present disclosure may include either the 24th or 25th aspect, further including the step of recovering the diluted waste slurry from an underflow outlet of the dilution water hydrocyclone.

[0090] The 27th aspect of the present disclosure may include any one of the 24th to 26th aspects and includes a step of introducing dilution water to the side of the dilution water hydrocyclone. The dilution water may be introduced tangentially, radially, or at a horizontal angle greater than 0 degrees and less than 90 degrees with respect to a radial straight line extending radially outward from the central axis of the dilution water hydrocyclone.

[0091] The 28th aspect of the present disclosure may include any one of the 24th to 27th aspects and includes a step of introducing dilution water into the dilution water hydrocyclone in a direction that generates a cyclone flow of dilution water having an angular direction opposite to the angular direction of the cyclone flow of the waste slurry.

[0092] The 29th aspect of the present disclosure may include any one of the 24th to 28th aspects, where the waste slurry may have a viscosity of 6% or less.

[0093] The 30th aspect of the present disclosure may include any one of the 24th to 29th aspects, where the ratio of the amount of dilution water to the flow rate of the waste slurry introduced into the dilution water hydrocyclone may be from 0.45:1 to 1.55:1.

[0094] The 31st aspect of the present disclosure D includes a step of mixing dilution water having an axial velocity V R with waste slurry having an axial velocity V R and the ratio of V D divided by V is from 0.25 to 0.75, and the axial velocity refers to the magnitude of the velocity vector in the axial direction. The 31st aspect may include any one of the 24th to 30th aspects.

[0095] The 32nd aspect of the present disclosure may include any one of the 24th to 31st aspects, where the supply slurry may include a fiber slurry.

[0096] The 33rd aspect of the present disclosure may further include a step of passing the received slurry through a papermaking process and may include any one of the 24th to 32nd aspects.

[0097] A 34th aspect of the present disclosure may include any one of the 24th to 33rd aspects, where the purifier may be a reverse flow hydrocyclone purifier.

[0098] A 35th aspect of the present disclosure may further include a step of restricting the flow of dilution water between the dilution water inlet and the waste slurry inlet, and restricting the flow can reduce the flow of solid fragments and contaminants returning into the purifier. This 35th aspect may include any one of the 24th to 34th aspects.

[0099] Although various embodiments of dilution devices and purification systems including dilution devices have been described herein, it should be understood that each of these embodiments and techniques may be used separately or in combination with one or more embodiments and techniques. It will be apparent to those skilled in the art that various modifications and changes can be made to the embodiments described herein without departing from the spirit and scope of the subject matter of the claims. Therefore, this specification is intended to include modifications and changes to the various embodiments described herein on the premise that such modifications and changes fall within the scope of the accompanying patent claims and their equivalents. The preferred embodiments of the present invention will be described below item by item. Embodiment 1 In a purification system for removing solid fragments and contaminants from a supply slurry, a purifier that functions to separate the supply slurry into a received slurry and a waste slurry, the waste slurry including at least a part of the solid fragments and contaminants from the supply slurry, and a dilution device disposed downstream of the purifier and fluidly coupled to the waste outlet of the purifier, the dilution device including a dilution water hydrocyclone, the dilution water hydrocyclone including a dilution water inlet, a cyclone flow section downstream of the dilution water inlet and having an upstream end and a downstream end, an underflow outlet disposed at the downstream end of the cyclone flow section, a waste slurry inlet disposed at the upper part of the dilution water hydrocyclone and coupled to the waste slurry outlet of the purifier, and a flow guide disposed between the dilution water inlet and the waste slurry inlet and functioning to direct the flow of dilution water from the dilution water inlet at least axially toward the cyclone flow section, a dilution device including a purification system including. Embodiment 2 The purification system according to Embodiment 1, wherein the flow guide is disposed radially between the dilution water inlet and the waste slurry inlet, and the flow guide restricts at least to some extent the flow of the dilution water from the axially directed dilution water inlet toward the waste slurry inlet. Embodiment 3 The purification system according to Embodiment 1 or 2, wherein the flow guide is made of a hollow tube having an inlet end and an outlet end coupled to the dilution water hydrocyclone in proximity to the waste slurry inlet, the inlet end of the hollow tube surrounding the waste slurry inlet, and the hollow tube extending axially from the waste slurry inlet toward the cyclone flow section. Embodiment 4 The purification system according to Embodiment 3, wherein the outlet end of the flow guide is disposed within the inlet section of the dilution water hydrocyclone. Embodiment 5 The outlet end of the flow guide has a flat axial surface, the flow guide includes a plurality of openings extending through the flow guide from the outer surface to the inner surface of the flow guide, or the flow guide includes one or more anti-rotation tabs coupled to the inner surface of the hollow tube, the purification system according to Embodiment 3 or 4. Embodiment 6 The dilution water hydrocyclone includes an inlet section defined between the waste slurry inlet and the cyclone flow section, and the flow guide has an axial length of 50% or more of the axial length of the inlet section. The purification system according to any one of Embodiments 1 to 5. Embodiment 7 The flow guide and the main body of the dilution water hydrocyclone define an annular flow region disposed between the flow guide and the main body, and the dilution water inlet is in fluid communication with the annular flow region. The purification system according to any one of Embodiments 1 to 6. Embodiment 8 The purification machine includes a reverse flow hydrocyclone purification machine. The purification system according to any one of Embodiments 1 to 7. Embodiment 9 The purification machine includes a hydrocyclone purification machine including a slurry inlet, a tapered section, an overflow outlet proximate to the wide end of the tapered section, and a waste outlet downstream of the narrow end of the tapered section. The hydrocyclone purification machine functions to generate a cyclone flow that separates the supply slurry into waste slurry at the waste outlet and received slurry at the overflow outlet. The waste slurry includes solid fragments, contaminants, or both. The purification system according to any one of Embodiments 1 to 8. Embodiment 10 A purification system assembly including a plurality of purification systems according to any one of Embodiments 1 to 9, wherein the plurality of purification systems operate in parallel. A purification system assembly. Embodiment 11 In a method of removing solid fragments and contaminants from a supply slurry, Introducing the supply slurry into a purification machine that functions to generate a cyclone flow that separates the supply slurry into waste slurry and received slurry, wherein the waste slurry includes at least a portion of the solid fragments and contaminants. A step. Passing the waste slurry through a dilution water hydrocyclone fluidly coupled to the waste outlet of the purification machine, the dilution water hydrocyclone including a cyclone flow section, a dilution water inlet upstream of the upstream end of the cyclone flow section, a waste slurry inlet upstream of the upstream end of the cyclone flow section, an underflow outlet at the downstream end of the cyclone flow section, and a flow guide disposed between the waste slurry inlet and the dilution water inlet. A step. A step of introducing dilution water into the dilution water hydrocyclone through the dilution water inlet, wherein by introducing the dilution water, a cyclone flow is established in an annular flow region defined between the flow inducer and the inner surface of the dilution water hydrocyclone, and A step of contacting the dilution water with the waste slurry at the outlet end of the flow inducer, wherein by contacting the dilution water with the waste slurry, at least a part of the dilution water is mixed with the waste slurry to reduce or prevent clogging of the purifier, the diluter, or both, A method comprising the steps. Embodiment 12 The method according to Embodiment 11, further comprising a step of recovering the received slurry from the overflow outlet of the purifier and a step of recovering the diluted waste slurry from the underflow outlet of the dilution water hydrocyclone. Embodiment 13 The method according to Embodiment 11 or 12, comprising a step of introducing the dilution water into a side portion of the dilution water hydrocyclone. Embodiment 14 The method according to any one of Embodiments 11 to 13, comprising a step of introducing the dilution water into the dilution water hydrocyclone in a direction that generates a cyclone flow of the dilution water having an angular direction opposite to the angular direction of the cyclone flow of the waste slurry. Embodiment 15 The dilution water having an axial velocity V D is mixed with the waste slurry having an axial velocity V R , and the ratio of V R divided by V D is from 0.25 to 0.75, and the axial velocity refers to the magnitude of the velocity vector in the axial direction. The method according to any one of Embodiments 11 to 14.

Explanation of Symbols

[0100] 100 Purification System 102 Feed Slurry 104 Dilution Water 110 Purifier 112 Main Body 114 Slurry Inlet 116 Overflow Outlet 118 Waste Outlet 119 Inlet Chamber 120 Tapered Section 122 Received Slurry 124 Waste Slurry 130 Dilution Device 132 Dilution Water Hydrocyclone 138 Dilution Water Inlet 139 Inlet Section 140 Cyclone Flow Section 142 Underflow Outlet 143 Discharge Conduit 144 Waste Slurry Inlet 148 Inlet Passage 150 Flow Inducer 154 Flow Inducer Wall 156 Inlet End 158 Outlet End 163 Anti-Rotation Tab 166 Annular Flow Region 170 Diluted Waste Slurry 180 Mixing Region 300 Purification System Assembly

Claims

1. In a purification system for removing solid fragments and contaminants from a supplied slurry, a purifier that functions to separate the supplied slurry into a received slurry and a waste slurry, the waste slurry including at least a portion of the solid fragments and contaminants from the supplied slurry, and a dilution device disposed downstream of the purifier and fluidly coupled to a waste outlet of the purifier, the dilution device including a dilution water hydrocyclone, the dilution water hydrocyclone including a dilution water inlet, a cyclone flow section downstream of the dilution water inlet and having an upstream end and a downstream end, the cyclone flow section having a tapered shape in which an inner diameter of the upstream end is larger than an inner diameter of the downstream end, an underflow outlet disposed at the downstream end of the cyclone flow section, a waste slurry inlet disposed at an upper portion of the dilution water hydrocyclone and coupled to a waste slurry outlet of the purifier, and a flow guide disposed between the dilution water inlet and the waste slurry inlet, the flow guide functioning to direct the flow of dilution water from the dilution water inlet axially at least toward the cyclone flow section, the flow guide restricting at least to some extent the axially directed flow of dilution water from the dilution water inlet toward the waste slurry inlet and being cylindrical, a dilution device including a purification system comprising.

2. The purification system according to claim 1, wherein the flow guide is disposed radially between the dilution water inlet and the waste slurry inlet.

3. The purification system according to claim 1 or 2, wherein the flow guide is made of a hollow tube having an inlet end and an outlet end coupled to the dilution water hydrocyclone in proximity to the waste slurry inlet, the inlet end of the hollow tube surrounding the waste slurry inlet, and the hollow tube extending axially from the waste slurry inlet toward the cyclone flow section.

4. The purification system according to claim 3, wherein an outlet end of the flow guide is disposed within an inlet section of the dilution water hydrocyclone.

5. The outlet end of the flow guide has a flat axial surface, the flow guide includes a plurality of openings extending through the flow guide from an outer surface of the flow guide to an inner surface of the flow guide, or the flow guide includes one or more anti-rotation tabs coupled to an inner surface of the hollow tube, the purification system according to claim 3 or 4.

6. The dilution water hydrocyclone includes an inlet section defined between the waste slurry inlet and the cyclone flow section, and the flow guide has an axial length of 50% or more of the axial length of the inlet section. The purification system according to any one of claims 1 to 5.

7. The flow guide and the main body of the dilution water hydrocyclone define an annular flow region disposed between the flow guide and the main body, and the dilution water inlet is in fluid communication with the annular flow region. The purification system according to any one of claims 1 to 6.

8. The purification machine includes a reverse flow hydrocyclone purification machine. The purification system according to any one of claims 1 to 7.

9. The purification machine includes a hydrocyclone purification machine including a slurry inlet, a tapered section, an overflow outlet proximate to the wide end of the tapered section, and a waste outlet downstream of the narrow end of the tapered section. The hydrocyclone purification machine functions to generate a cyclone flow that separates the supply slurry into waste slurry at the waste outlet and receiving slurry at the overflow outlet. The waste slurry includes solid fragments, contaminants, or both. The purification system according to any one of claims 1 to 8.

10. A purification system assembly including a plurality of purification systems according to any one of claims 1 to 9, wherein the plurality of purification systems operate in parallel. A purification system assembly.

11. In a method of removing solid fragments and contaminants from a supply slurry, Introducing the supply slurry into a purification machine that functions to generate a cyclone flow that separates the supply slurry into waste slurry and receiving slurry, wherein the waste slurry includes at least a portion of the solid fragments and contaminants. A step, Passing the waste slurry through a dilution water hydrocyclone fluidly coupled to the waste outlet of the purification machine, the dilution water hydrocyclone including a cyclone flow section, a dilution water inlet upstream of the upstream end of the cyclone flow section, a waste slurry inlet upstream of the upstream end of the cyclone flow section, an underflow outlet at the downstream end of the cyclone flow section, and a flow guide disposed between the waste slurry inlet and the dilution water inlet. The cyclone flow section has a tapered shape with an inner diameter at the upstream end larger than the inner diameter at the downstream end, and the flow guide is cylindrical. A step, A step of introducing dilution water into the dilution water hydrocyclone through the dilution water inlet, wherein by introducing the dilution water, a cyclone flow is established in an annular flow region defined between the flow inducer and the inner surface of the dilution water hydrocyclone, and A step of contacting the dilution water with the waste slurry at the outlet end of the flow inducer, wherein by contacting the dilution water with the waste slurry, at least a part of the dilution water is mixed with the waste slurry to reduce or prevent clogging of the purification machine, the dilution water hydrocyclone, or both, A method comprising the steps.

12. The method according to claim 11, further comprising a step of recovering the received slurry from the overflow outlet of the purification machine and a step of recovering the diluted waste slurry from the underflow outlet of the dilution water hydrocyclone.

13. The method according to claim 11 or 12, comprising a step of introducing the dilution water to a side portion of the dilution water hydrocyclone.

14. The method according to any one of claims 11 to 13, comprising a step of introducing the dilution water into the dilution water hydrocyclone in a direction that generates a cyclone flow of the dilution water having an angular direction opposite to the angular direction of the cyclone flow of the waste slurry.

15. Axial velocity V Ｄ Mixing the dilution water having the axial velocity V Ｒ with the waste slurry having the axial velocity V Ｒ wherein the ratio of V divided by V Ｄ is from 0.25 to 0.75, and the axial velocity refers to the magnitude of the velocity vector in the axial direction. The method according to any one of claims 11 to 14.

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