Patent Publication Number: US-2013240457-A1

Title: Feed Dilution System for a Thickener or Settling Tank

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to thickener/clarifier settling tanks used to separate liquid and solid components of an influent feed slurry and specifically relates to feedwell apparatus employed in such thickener/clarifiers to enhance the clarification process. More specifically, the invention relates to a feed dilution system and method that delivers a diluted solids slurry to a feedwell of a thickener or clarifier tank. 
     Thickener/clarifier tanks are used in a wide variety of industries to separate influent feed slurry comprising a solids, or particulate, containing fluid to produce a “clarified” liquid phase having a lower concentration of solids than the influent feed slurry and an underflow stream having a higher concentration of solids than the influent feed slurry. Thickener/clarifier tanks conventionally comprise a tank having a floor and a continuous wall, which define a volume within which the clarification process takes place. Thickener/clarifier tanks also include an influent feed pipe for delivering influent feed to the tank, an underflow outlet for removing settled solids from the tank and a fluid discharge outlet for directing clarified liquid away from the tank. Thickener/clarifier settling tanks may also include a rake assembly having rake arms for sweeping along the floor of the tank, and may include an overflow launder or bustle pipe for collecting clarified liquid near the top of the tank. 
     Thickener/clarifier tanks of the type described operate by introducing an influent feed stream into the volume of the tank where the influent is retained for a period long enough to permit the solids to settle out by gravity from the fluid. The solids that settle to the bottom of the tank produce a sludge bed near the bottom of the tank, which is removed through the underflow outlet. Clarified liquid is formed at or near the top of the thickener/clarifier tank and is directed away from the tank for further processing or disposal. Settling of solids may be enhanced in some applications by the addition of a flocculent or polymer that forms agglomerates that settle more readily. In many applications, an objective of fluid clarification is to enhance the settling process to achieve a high throughput of solids, and thereby enhance solids recovery. 
     Many thickener/clarifier tanks are constructed with a feedwell, usually centrally located within the tank, into which the influent feed stream is delivered. The feedwell generally serves the purpose of reducing the fluid velocity of the incoming influent feed stream so that the energy in the stream may be dissipated to some degree before entering the tank. Dissipation of energy in the influent feed stream lessens the disruptive effect that the incoming influent feed has on the settling rate of the solids in the tank. In other words, introduction into a thickener/clarifier of an influent feed stream under high fluid velocity tends to cause turbulence in the tank and compromises the settling rate of solids. A feedwell may be structured in a variety of ways, therefore, to create or enhance dissipation of energy in the influent feed. For example, the feedwell and influent feed pipe may be structured to introduce influent feed to the feedwell at two opposing directions and into an annular space, such as is disclosed in U.S. Pat. No. 4,278,541 to Eis, et al. 
     In many feedwell assemblies, the influent feed pipe is incorporated into a dilution feed system including a mixing conduit with a downstream end connected to the feedwell and an upstream end that receives both a slurry stream from a feed pipe and a diluting liquid. The feed pipe is provided at its outlet end with a nozzle usually having a circular outlet opening located proximate the upstream end of the mixing conduit. 
     The mixing conduit may take the form of a classical submerged pipe or tube or alternatively an open channel form in which a mixing zone is open to the atmosphere. It has been observed that mixing of the incoming solids slurry with thickener overflow or dilution liquor may be less complete or effective in the open channel design. It has been observed further that the dilution liquor stream flows along the wall of the mixing channel, outside of the concentrated slurry jet from the feed pipe nozzle, and only partially mixes with the concentrated slurry jet. This type of performance is not ideal for a feed slurry dilution device that is mixing flocculant with a diluted slurry prior to entering a gravity thickener. In a best case scenario, a combined slurry stream entering the thickener or feedwell should be diluted to a very uniform concentration of solids across the entire cross-sectional area of the open channel. 
     OBJECTS OF THE INVENTION 
     It is an object of the present invention to provide an improved feed dilution system and method for a feedwell assembly of a thickener/clarifier/settling tank. 
     A more specific object of the present invention is to provide such a feed dilution system and method which provides a substantially uniform solids distribution across the cross-section of a feed stream entering a feedwell. 
     Another specific object of the present invention is to provide such a feed dilution system and method which produces an improved or enhanced mixing of an incoming slurry with a flocculent. 
     These and other objects of the present invention will be apparent from the drawings and description herein. Although every object of the invention is believed to be attained by at least one embodiment of the invention, there is not necessarily any one embodiment of the invention that achieves all of the objects of the invention. 
     SUMMARY OF THE INVENTION 
     Applicant&#39;s have discovered that if the motive jet, that is, the output stream of the feed pipe nozzle, is non-circular and flatter and thus broader across the width of the open channel instead of a tubular stream flowing down the center of the mixing channel, the motive flow is more conducive to mixing the solids and dilution fluids together in an area closer to the dilution-liquid suction inlet of the mixing channel and that the flows are better mixed prior to the exit from the mixing channel, hence producing a more uniform solids concentration over the entire open channel as it enters the feedwell. 
     While a nozzle with a planar or rectangular output opening produces a widening or flattening of the inlet motive jet and enhances slurry dilution and better utilization of the dilution liquor to provide better and/or less flocculant consumption, a nozzle having an outlet opening with a modified cruciform configuration yields even better results. Preferably, the upper arm of the cross-shaped configuration is reduced in length relative to the lower leg, thereby directing the flow more downwardly as well as more across the width of the open channel. Not only is the inlet flow no longer circular but it is distributed even better than in the case of a flat jet entering the mixing channel. With the modified cruciform nozzle, the inlet flow is nearly flat horizontally while having a downward component which serves to better mix the slurry at the bottom of the channel. 
     It is to be noted that the arms or legs of the nozzle output opening can be of different widths to yield higher or lower velocities in different directions. Likewise, the horizontal arms may have different lengths than both of the vertical arms. The nozzle may be rotatably, variously snap fit, or otherwise mounted to the slurry feed pipe so as to enable adjustment of the orientation of the outlet opening and/or removal and replacement of the same. 
     A feed dilution system for a thickener or settling tank comprises, in accordance with the present invention, a slurry feed pipe, a nozzle attached to a downstream end of the feed pipe, a mixing conduit, and a feedwell disposed inside the thickener or settling tank. At least a portion of the nozzle is disposed proximate an upstream end of the mixing conduit. A downstream end of the mixing conduit is functionally attached to the feedwell, perhaps at or to its outer wall, so that the mixing conduit communicates with the feedwell. Pursuant to the invention, the nozzle has an outlet opening or orifice configured to generate an initial stream of slurry from the feed pipe into an upstream end of the mixing conduit that is extended from a first side of the mixing conduit to a substantially opposite second side in a first direction transverse to the mixing conduit so as to enhance entrainment of dilution fluid flow into the slurry stream and concomitantly produce a more uniform solids concentration across a stream flowing from the mixing conduit into the feedwell. In addition, the outlet opening is generally shaped asymmetrically towards a third side of the mixing conduit in a second direction generally transverse to the first direction so as to bias the initial stream of slurry towards the one side, where the second direction is substantially perpendicular to the first direction. 
     In accordance with a further feature of the invention, the outlet opening of the nozzle is symmetric about an axis extending along the second direction and asymmetric about an axis extending along the first direction. In various embodiments of the invention, the outlet opening of the nozzle has a pair of first arms or legs that are disposed symmetrically on opposite sides of the axis of symmetry and extend at least partially in the first direction, the outlet opening having at least one second arm extending at least partially in the second direction and disposed on one side of the first arms, towards the third side. 
     In one embodiment of the invention, the outlet opening of the nozzle has a cruciform shape. The cruciform shape may comprise multiple arms (or legs) extending away from a node or junction. The arms include two first arms extending away from one another on opposite sides of the node or junction along the first direction, and further include at least one second arm extending away from the node or junction on one side of the first arms in the second direction. The cruciform shape may also include an additional second arm extending away from the at least one second arm on a side of the node or junction opposite the at least one second arm, where the additional second arm is generally substantially shorter than the at least one second arm. 
     In various orientations of the nozzle about a flow axis, the first arms and the first direction are at least approximately horizontal, while the second arms constitute lower and upper arms of the cruciform shape. The length of the upper or additional second arm is typically less than one-half the length of the lower second arm. 
     In preferred embodiments of the invention, the nozzle outlet opening has exactly one axis of symmetry, with at least a portion of the lower second arm extending along the axis of symmetry. 
     The first arms are typically at least approximately of equal lengths. 
     In one embodiment of the present invention, the first arms are collinear with one another, and the second arms are collinear with one another. 
     The nozzle may be rotatably, snap fit, bolted, or otherwise mounted to the feed pipe and it may be removable and/or replaceable. 
     The mixing conduit may take any number of forms, including that of an open or closed channel having a substantially rounded, v-shaped, rectangular or approximately rectangular cross-section with one or more sharp or rounded lower corners. The outlet opening of the nozzle is asymmetrically configured to bias the initial stream to remove settled particles from the corners of the mixing conduit. 
     In accordance with the present invention, a nozzle disposable at a downstream end of a feed pipe in a feed dilution system for a thickener or settling tank comprises a nozzle body having an inlet end and an outlet end, the outlet end being provided with an outlet opening or orifice having a configuration that may be symmetric about an axis and asymmetric about all lines extending perpendicular to the axis. 
     The outlet opening of the nozzle may have multiple arms extending away from a node or junction, the arms including two first arms extending away from one another on opposite sides of the axis, the arms including at least one second arm extending away from the node or junction at least partially parallel to the axis. 
     The arms may include an additional second arm extending away from the at least one second arm on a side of the node or junction opposite the at least one second arm and at least partially parallel to the axis, the additional second arm being substantially shorter than the at least one second arm, the first arms being at least approximately of equal lengths. 
     In one embodiment of the present invention, the nozzle outlet opening has a strictly cruciform configuration wherein the first arms are collinear with one another about a first axis, and the second arms are collinear with one another and extend along a second axis. In this cruciform configuration, the outlet opening takes the form of a cross having a linear main branch and a linear cross-branch extending substantially perpendicularly to one another, the main branch having a first segment on one side of the cross branch and a second segment on an opposite side of the cross branch, the cross branch being disposed substantially closer to one end of the main branch than to an opposite end thereof, so that the first segment is substantially shorter than the second segment. The main branch typically but not necessarily bisects the cross branch. 
     The nozzle outlet opening typically has exactly one axis of symmetry, generally vertical, with at least a portion of the at least one second arm extending along that axis. However, in another embodiment of the present invention, the nozzle opening is generally tri-lobed, and may be variously oriented for the desired flow and mixing effect. Furthermore, the general term nozzle outlet or orifice also includes one or more, i.e., multiple openings, which may be sized, configured and arranged in various ways and configurations in order to produce the same enhanced mixing and other effects as the apparatus and methods disclosed and shown herein. Additionally, the general term nozzle outlet or orifice also includes an opening or openings which may be formed by the shape of the outer wall of the nozzle outlet or orifice. Furthermore, the shape of the end of the slurry feed pipe itself may actually form the so-called nozzle and/or outlet/opening of the feed pipe orifice. 
     The present invention also includes and describes a method of conditioning the slurry feed stream flowing into the feedwell of a thickener/clarifier or settling tank which is used as described and disclosed herein to enhance the entrainment of dilution fluid with the slurry feed stream, reduce the settling of solids in the mixing conduit, and generally enhance the mixing action therein. The method may further include the steps of educting the dilution liquid, perhaps from the tank itself, into the mixing conduit by way of momentum transfer responsive to the influent slurry feed stream, flocculating a resulting diluted slurry feed stream, and/or producing a substantially uniform solids concentration in the slurry feed stream across the width and depth of the mixing conduit as the slurry feed stream enters the feedwell. 
     A feedwell feed dilution system, method and associated nozzle opening or orifice in accordance with the present invention generally improves mixing in the mixing conduit. This is of particular benefit in generally rectangular open-channel type mixing conduits where the invention results not only in a more even or uniform distribution of solids across the stream entering the feedwell from the mixing conduit but also serves to prevent a buildup of particles along the lower corners of the mixing conduit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a vertical sectional view of a thickener/clarifier tank having a center pier supporting a rotating sludge raking structure and a feedwell assembly with a feed dilution system in accordance with the present invention. 
         FIG. 2  is a plan view of the thickener/clarifier tank of  FIG. 1 , taken on line II-II in  FIG. 1 . 
         FIG. 3  is a schematic perspective view of a feedwell assembly with a feed dilution system in accordance with the present invention. 
         FIG. 4  is a schematic vertical cross-sectional view of the feed dilution system of  FIG. 3 . 
         FIG. 5  is an end elevational view of a nozzle included in the feed dilution system of  FIGS. 1-4 , showing a nozzle outlet opening in accordance with the invention. 
         FIG. 6  is an end elevational view similar to  FIG. 5 , depicting another nozzle outlet opening in accordance with the invention. 
         FIG. 7  is a view similar to  FIGS. 5 and 6 , depicting a further nozzle outlet opening in accordance with the invention. 
         FIG. 8  is a view similar to  FIGS. 5-7 , depicting yet another nozzle outlet opening pursuant to the invention. 
         FIG. 9  is a view similar to  FIGS. 5-8 , depicting still another nozzle outlet opening pursuant to the invention. 
     
    
    
     DETAILED DESCRIPTION 
     As illustrated in  FIGS. 1 and 2 , a thickener/clarifier comprises a continuously operating thickening/settling tank  20  wherein a sludge raking structure  10  is supported for rotation upon a center pier  11 . A drive mechanism  12  of any suitable known construction is mounted atop the pier providing the driving torque for the rake structure. The pier also supports the inner end of an access bridge  13 . 
     Rake structure  10  comprises a central vertical cage portion or cage  14  surrounding the pier  11 , and rake arms of girder like construction extending rigidly from the cage. Rake structure  10  has one pair of long rake arms  15  and  16  opposite to one another, and a pair of short rake arms  17  and  18  disposed at right angles thereto, all arms having sludge impelling or conveying blades  19  fixed to the underside thereof. 
     Rake structure  10  operates in a settling tank  20  to which a feed suspension or feed pulp is supplied through a feed dilution system  21  terminating in a cylindrical feedwell body  22  which surrounds the top end portion of the rake structure and is supported by pier  11 . 
     Tank  20  may be of usual construction, comprising a bottom  24  of shallow inverted conical inclination, and formed with an annular sump  25  around the pier, to which settled solids or sludge are conveyed by rake structure  10 . Scraper blades  26 , unitary with rake structure  10  and substantially conforming to the profile of sump  25 , move the collected sludge to a point of delivery from the sump, as by way of a discharge pipe  27 . 
     Feed dilution system  21  is connected at a downstream end to feedwell body  22 . Feedwell body  22  has an annular floor panel  34  ( FIG. 2 ) with an inner edge  36  defining a circular opening  38  and an outer edge contiguous with a cylindrical sidewall  40  of the feedwell body. Feed dilution system  21  is connected to feedwell body  22  so as to deliver slurry stream  42  to flow along a circular path inside the feedwell body. Slurry stream  42  has a substantially circular inner boundary located generally above inner edge  36  and a substantially circular outer boundary located adjacent feedwell sidewall  40 . The inner and outer boundaries extend parallel to the path of the incoming slurry stream  42 . 
     As depicted in  FIG. 3  and more schematically in  FIG. 4 , feed dilution system  21  includes a slurry feed pipe  44 , a nozzle  46  attached to a downstream end of the feed pipe, and a mixing conduit  48  in the form of an open channel having lower corners  49  (only one shown). Feed dilution system  21  may be defined to further include feedwell body  22 . At least a portion of nozzle  46  is disposed proximate an upstream end  50  of mixing conduit  48 . A downstream end of mixing conduit  48  is functionally attached to feedwell sidewall  40  so that the mixing conduit communicates with the feedwell. In  FIG. 4 , reference designation  52  represents a bed of settled solids in settling tank  20 , pipe  54  being provided for removing the thickened underflow. 
     Nozzle  46  ( FIG. 4 ) generally comprises a nozzle body  92  having an inlet end  94  and an outlet end  96 , the outlet end being provided with outlet opening or orifice  56 . 
     As shown in  FIG. 5 , nozzle  46  may have a cruciform outlet opening  56  configured to generate an initial stream  58  ( FIG. 4 ) of slurry from feed pipe  44  into upstream end  50  of mixing conduit  48  that is extended from a first side  60  of the mixing conduit to a substantially opposite second side  62  in a first direction  64  transverse to the mixing conduit so as to enhance entrainment of dilution fluid or supernatant flow  66  ( FIG. 4 ) into the slurry stream  58  and concomitantly produce a substantially uniform solids concentration across a stream  68  flowing from the mixing conduit into feedwell body  22 . Outlet opening  46  is shaped asymmetrically towards a third side  70  of mixing conduit  48  in a second direction  72  transverse to the mixing conduit so as to bias the initial stream  58  of slurry towards the third side  70 , where the second direction  72  is substantially perpendicular to the first direction  64 . 
     Flocculent may be delivered via a tube or tubes  74  into the dilution fluid or supernatant flow  66  at upstream end  50  of mixing conduit  48  and additionally at points  75 ,  77  further downstream along the mixing conduit, now including both the slurry feed stream and dilution fluid. 
     As further shown in  FIG. 5 , outlet opening  56  of nozzle  46  is substantially symmetric about an axis  76  extending along the second direction  72  and asymmetric about all lines extending parallel to the first direction  64 . The term “substantially symmetric” is used herein to denote a degree of symmetry that produces balanced mixing from one side to an opposite side across the mixing conduit  48 . This term is intended to encompass variations in arm length that are measurable on a linear scale but do not result in asymmetric flow patterns. 
     Outlet opening  56  has a pair of first arms or legs  78 ,  80  that are disposed symmetrically on opposite sides of axis  76  and extend in the first direction  64 . Outlet opening  56  also has a second arm or leg  82  extending in the second direction  72  and disposed on a lower side of arms  78 ,  80  towards the third side  70  of mixing conduit  48 . 
     Nozzle outlet opening  56  particularly has a cruciform shape wherein the multiple arms (or legs)  78 ,  80 ,  82  extend away from a node or junction  84 . Arms  78  and  80  are collinear with one another, of equal width and are disposed on opposite sides of node or junction  84  along direction  64 . Arm or leg  82  may be of the same width (or not) as arms  78 ,  80  and extends away from node or junction  84  on one side of arms  78 ,  80  in direction  72 . Outlet opening  56  also includes an additional second arm  86  extending away from node or junction  84  on a side thereof opposite arm  82  and collinearly with arm  82 . This additional second arm  86 , preferably collinear with arm  82 , is substantially shorter than arm  82  and is no more than about one-half the length of arm  82 . 
     Nozzle  46  may be variously mounted to feed pipe  44  for rotation about a longitudinal flow axis  88  so as to enable an adjustment in the angular orientation of opening  56  or removal and replacement thereof. Generally, lower arm or leg  82  and upper arm or leg  86  are oriented vertically, while arms  78 ,  80  are horizontal. However, one might rotate nozzle  46  to as to provide some deviation in outlet opening orientation from the vertical. Accordingly, in some orientations of nozzle  46  about longitudinal flow axis  88 , arms  78  and  80  and direction  64  are at least approximately horizontal, with arms  82  and  86  constituting lower and upper arms of the cruciform shape. 
     Nozzle outlet opening  56  has exactly one axis of symmetry  76 , with lower arm  82  extending along that axis. Arms  78  and  80  are at least approximately of equal lengths. While ends  90  of the various arms  78 ,  80 ,  82 ,  86  have arcuate edges, the ends may alternatively take a flat or linear form (compare  FIGS. 6-8 ). 
     Outlet opening  56  takes the form of a cross having a linear main branch formed by arms  82  and  86  and a linear cross-branch consisting of arms  78  and  80  (and node or junction  84 ), the main branch and the cross-branch extending substantially perpendicularly to one another. Arms  78  and  80  constitute branch segments on opposite sides of the cross branch. The cross branch is disposed substantially closer to one end of the main branch than to an opposite end thereof, so that the upper segment, arm  86 , is substantially shorter than the lower segment, arm  82 . The main branch typically but not necessarily bisects the cross branch. 
     It is to be noted that the asymmetrical configuration of outlet opening  56 , with the biasing of the flow downwardly owing to the larger size of arm  82 , serves to remove settled particles from the corners of open channel conduit  48 . It is surmised that a higher velocity or turbulence is created, which lifts particles away from the bottom of the mixing conduit  48  for entrainment with the diluted slurry stream. 
       FIG. 6  shows an alternative outlet opening  98  for nozzle  46 , having a configuration that is substantially symmetric about an axis  100  and asymmetric about all lines extending perpendicular to said axis. Opening  98  has multiple arms  102 ,  104 ,  106  extending away from a node or junction  108 . Arms  102 ,  104  extend collinearly in a first direction  110  on opposite sides of axis  100 . Arm  105  extends away from node or junction  108  parallel to and collinear with axis  100 . Arms  102  and  104  define a first branch of the approximately cruciform outlet opening  98 , while arm  106  constitutes a second branch that substantially bisects the first branch. 
     Like nozzle opening  56 , outlet opening  98  is configured to generate an even or uniform distribution of solids in the exit slurry stream  68  and to entrain particles in a lower portion of the mixing conduit  48  to prevent accumulation of the particles particularly in the corners of the conduit. Arms  102 ,  104 ,  106  have straight ends  112  but may have arcuate or curved end edges as shown in  FIG. 5 . 
     As illustrated in  FIG. 7 , another outlet opening  114  for nozzle  46  has a substantially cruciform configuration that is a modification of outlet opening  56  of  FIG. 5 . Opening  114  has been modified to include a pair of fingers or extensions  116  and  118  angled away from one another at a free end of arm  82 . 
     Like nozzle openings  56  and  98 , outlet opening  114  is configured to generate an even or uniform distribution of solids in the exit slurry stream  68  and to entrain particles in a lower portion of the mixing conduit  48  to prevent accumulation of the particles particularly in the corners of the conduit. Arms  78 ,  80 ,  82  and  86  are shown in  FIG. 7  as having linear rather than arcuate extremities. 
       FIG. 8  depicts a further alternative outlet opening  120  for nozzle  46 , that has a modified X configuration with a pair of arms  122 ,  124  and a pair of legs (or lower arms)  126 ,  128  connected to one another at a node or junction  130 . Outlet opening  120  has an axis of symmetry  132  and is asymmetric about any line extending perpendicular to the axis, in the plane of the opening. Arms  122 ,  124  are of substantially equal lengths and extending at a first angle A 1  relative to one another. Legs  126 ,  128  are of substantially equal lengths and extending at a second angle A 2  relative to one another. Angle A 1  is significantly larger than angle A 2 . 
       FIG. 9  depicts yet another alternative outlet opening  140  for nozzle  46  that has a three-armed or tri-lobed configuration with three arms or lobes  142 ,  144  and  146  extending from a, possibly centrally located, node or junction  150 . Outlet opening  140  has an axis of symmetry  152  and is asymmetric about any line extending perpendicular to the axis, in the plane of the opening. The lobes  142 ,  144  and  146  as shown are of substantially equal lengths and dimensions, and angularly substantially equally displaced about node or junction  150 . Of course, variations in their respective sizes and/or angular locations could be made in order to improve their effectiveness in entraining and mixing particles in the mixing conduit  48  and thus the exit slurry stream  68 . 
     The present invention further includes a method of conditioning a slurry feed stream flowing into the feedwell of a thickening or settling tank, said tank including a tank inlet system comprising an influent slurry feed pipe, nozzle and orifice directing the influent slurry feed stream into a mixing conduit, said mixing conduit including a bottom and leading to the feedwell, said method, for example, using the apparatus as shown in various of the accompanying  FIGS. 1-9 . 
     This method would include the steps of flowing the influent slurry feed stream through the feed pipe, nozzle and orifice into the mixing conduit, using the nozzle orifice to shape the influent slurry feed stream in order to enhance the entrainment of dilution fluid with the influent slurry feed stream and also to bias at least a portion of the influent slurry feed stream towards the bottom of the mixing channel in order to reduce the settling of solids and enhance the mixing action in the mixing channel, thereby forming a diluted and well mixed slurry feed stream, and flowing the resulting diluted and mixed slurry feed stream into the feedwell. 
     The method could also include the additional steps of educting the flow of the dilution fluid into the mixing channel by way of using the transfer of momentum between the influent slurry feed stream and the dilution fluid, flocculating the incoming dilution fluid and/or the slurry feed stream and the dilution fluid within the mixing channel, and/or producing a substantially uniform solids concentration within the resulting diluted and mixed slurry feed stream flowing into the feedwell. 
     Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. It is believed that the invention is useful in virtually any type of feedwell assembly, with or without the addition of flocculent, with or without slurry dilution by eduction, with singular or multiple infeed paths, with or without spill lips (i.e., annular bottom panels or shelves in the feedwell bodies), etc. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof which is only defined by the broadest possible interpretation of the appended claims and their equivalents. 
     Furthermore, a contractor or other entity may provide, or be hired to provide, the apparatus and/or method such as those disclosed in the present specification and shown in the figures. For instance, the contractor may receive a bid request for a project related to designing a system for producing a particular slurry feed stream or may offer to design such a method and accompanying system. The contractor may then provide the apparatus and/or method such as those discussed above. The contractor may provide such a method by selling the apparatus and/or method or by offering to sell the apparatus and/or method, and/or the various accompanying parts and equipment to be used with and/or for said method. The contractor may provide a method and/or related equipment that are configured to meet the design criteria of a client or customer. The contractor may subcontract the fabrication, delivery, sale, or installation of a component of, or of any of the devices or of other devices contemplated for use with the method. The contractor may also maintain, modify or upgrade the provided devices and their use within the general method. The contractor may provide such maintenance or modifications by subcontracting such services or by directly providing those services.