Abstract:
Apparatus and method in which a solid or liquid additive is dispensed within a mixing chamber for mixing with a fluid from the pressurized fluid flow line and is effective mixed in a vortex under vacuum while precluding contamination of the unused additive.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 14/505,228, filed on Oct. 2, 2014, which is incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     BACKGROUND 
     1. Field 
     The present disclosure provides an apparatus and method for introducing an additive material into a pressurized fluid flow line. More particularly, the disclosure provides an apparatus and method in which a solid or liquid additive is dispensed within a mixing chamber for mixing with the fluid from the pressurized fluid flow line and is effective mixed. 
     2. Description of the Related Art 
     Apparati for introducing an additive material into a fluid flow line are well known. This includes a dispersing apparatus for metering a dry particulate material into a liquid utilizing a feed rate rod adjustably moveable vertically to stop or meter the flow into the liquid supply. This also includes a dispersing apparatus for metering the dispersing of dry particulate material into a liquid using a cylindrical mixing container, a mixing chamber liquid inlet generally tangentially disposed, a particulate supplying unit having a supply unit outer piping and a particulate supply unit particulate inlet. 
     Unfortunately, the prior art does not effectively address each of the myriad of handling issues specific to problematic additive materials due the additive&#39;s physical characteristics. Additive materials may be difficult to place into solution, may be shear sensitive, may be difficult to “wet” during the blending process, may tend to form unblended collections or unwetted product, particularly in the case of polymers, and may provide difficult to convey to the blending device depending on the volume of additive. Moreover, these additives may be subject to contamination immediately prior to or following a blending event. Further, these additives may pose health issues requiring isolation not only from atmosphere, but from personnel. 
     It is known in the prior art that dry additives may produce dust and or fumes that present safety and maintenance issues with equipment and may pose a danger to operating personnel who must be in close proximity to the blending process. Dry polymers, for example, tend to dust into the atmosphere during the conveying process and float to surfaces adjacent to the blending equipment, immediately resulting in waste. Upon absorption of moisture from the atmosphere, this dry polymer dust may then form a surface coating presenting both a safety issue for personnel and the need for extensive cleaning to remove the film. Silica sand and other dry additives used in high volumes for hydraulic fracturing in the oil field, for example, are subject to undesirable contamination. During blending of such large volumes, the dust generated carries silica, which poses a health hazard. 
     It is also known in the prior art that additives create handling difficulties at the beginning or end of a blending cycle when blending with a liquid. The beginning or end of a mixing or blending event would often create partial or complete clogging as there has been no clear method of preventing contact between the product and blending liquid. 
     Similarly, it is known in the prior art that isolating the moisture-sensitive material from the fluid cylindrical mixing container can prove difficult. In these systems, it has been difficult to prevent moisture migrating from the cylindrical mixing container to the moisture-sensitive material immediately adjacent to the separation point of the apparatus. As a result, over time, the additive material has been known to absorb moisture and clump, preventing a free flowing of product during subsequent feed/blending events. 
     Thus, there is a need for an apparatus and method of use which blends a variety of problematic liquid and dry materials into a closed, pressurized liquid line, which permits initiation and cessation of blending events without adversely affecting the process such as by clogging or changes in handling characteristics of the product following periods of inactivity, and which conveys the product to a cylindrical mixing container without contamination from the atmosphere. There is a further need for an apparatus and method of use which conveys the product from large bulk storage without the need of augers, pumps and other mechanical means of transport, which prevents contamination of moisture sensitive materials at the point of interface with liquid, and which precisely controls the delivery rate of product to a liquid mixing process. Finally, there is a need for an apparatus and method of use which precisely adjusts the energy acting on the product during the mixing process and which provides an alternate method of packaging of difficult materials. 
     SUMMARY 
     It is therefore, a principle object of the present disclosure to provide an apparatus for mixing of an additive material into a fluid and method of use which includes a cylindrical mixing container, an additive supply unit, a linear actuator coupled to the additive supply unit and adapted to withdraw the additive supply unit from the cylindrical mixing container to a point above an isolating valve, an outlet line adapted for connection to the cylindrical mixing container at its outlet and to an inlet of a pump, a fluid supply adapted for communication with a restricting valve which is adapted for communication with a liquid inlet to the cylindrical mixing container. The cylindrical mixing container is constructed to have a mixing container top side, a mixing container bottom side, a mixing container sidewall. The cylindrical mixing container has a cylindrical mixing container outlet through the mixing container bottom wall aligned with the longitudinal cylindrical mixing container axis. The cylindrical mixing container has a cylindrical mixing container liquid inlet through the mixing container sidewall bounded at a cylindrical mixing container inlet bottom by the cylindrical mixing container bottom wall and is generally tangentially disposed to an inner peripheral surface of the cylindrical mixing container. The additive has an additive supply unit longitudinal axis aligned with the longitudinal cylindrical mixing container axis, an additive supply unit outer piping having an additive supply unit outer piping top end and an additive supply unit outer piping bottom end, an additive supply unit inlet into the additive supply unit outer piping at the additive supply unit outer piping top end, and an additive supply unit shaft slidably positioned within the additive supply unit outer piping from the supply unit outer piping top end to beyond the supply unit outer piping bottom end. The apparatus further includes an additive supply unit collar at the supply unit outer piping bottom end maintaining the additive supply unit shaft on the additive supply unit longitudinal axis. An additive supply unit disc is affixed perpendicular to the additive supply unit shaft at the bottom end of the additive supply unit shaft, and a motor is coupled to the additive supply unit shaft. 
     A method is further provided for the apparatus, wherein the isolating valve is opened, the additive supply unit outer piping bottom end is deployed into the cylindrical mixing container, and the additive supply unit shaft and the additive supply unit disc are rotated. A vacuum is drawn on the cylindrical mixing container, and the restricting valve is opened to permit communication of the fluid from the fluid supply to the cylindrical mixing container liquid inlet. The additive material is introduced into the additive supply unit outer piping at the additive supply unit inlet, the additive supply unit outer piping bottom end is retracted out of the cylindrical mixing container. The isolating valve is closed. 
     The apparatus thereby provides a smooth, continuous introduction of an additive into a flow stream without cross contamination of the product or blending system between times of operation. 
     The foregoing and other objectives, features and advantages of the disclosure will be more readily understood upon consideration of the following detailed description of the disclosure, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the described features, advantages and objects of the disclosure, as well as others which will become apparent, are attained and can be understood in detail, more particular description of the disclosure briefly summarized above may be had by reference to the embodiments thereof that are illustrated in the drawings, which drawings form a part of this specification. It is to be noted, however, that the appended drawings illustrate only a typical preferred embodiment of the disclosure and are therefore not to be considered limiting of its scope as the disclosure may admit to other equally effective embodiments. 
         FIG. 1  illustrates a side view of an embodiment of the apparatus in a deployed or second position. 
         FIG. 2  illustrates a top view of an embodiment of the cylindrical mixing container when viewed downward along plane A-A. 
         FIG. 3  illustrates a method of blending or mixing is accomplished according to the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to  FIG. 1 , a side view of an embodiment of an apparatus  100  for mixing and blending of an additive material  190  into a fluid  180  is illustrated in a deployed or second position. The apparatus includes a vertically-oriented cylindrical mixing container  102  and an additive supply unit  116 , together with a linear actuator  124  coupled to the additive supply unit  116 , an outlet line  153  in communication with the cylindrical mixing container  102 , and a fluid supply  156 , which may be a container, in communication, via a pressure controller  184  and a restricting valve  158 , with the cylindrical mixing container. The additive  190  may be a liquid or solid and may be a combination of additives. The fluid  180  from the fluid supply  156  is preferably provided to the cylindrical mixing container  102  at a predetermined or adjusting pressure by a pressure controller  184 , which may be accomplished by maintaining a level of the fluid  180  in a pressure controller tank  186  at a constant level, such as by use of a float valve  182 , or other systems known in the art, to maintain a level of fluid  180 , in connection with an open, i.e. vented to atmosphere, pressure controller tank  186 , or by use of a another system configured to provide flow of the fluid  180  from the fluid supply  156  at a fixed and/or constant pressure. Where a pressure controller  184  incorporating a float valve  182  is used, the level of fluid  180  in the pressure controller  184  is maintained at a constant height, so that when fluid  180  is dispersed into the cylindrical mixing container  102 , additional fluid  180  is permitted to enter the pressure controller  184  from the fluid supply  156 . Alternatively, the pressure controller  184  may be adjusted to ensure the height of the vortex of the fluid  180  generated within the cylindrical mixing container  102  does not rise so far along the mixing container sidewall  138  as to result in fluid  180  rebounding onto the additive supply unit  116 , potentially immediately altering the pressure of the fluid  180  entering the cylindrical mixing container  102  to compensate for the volume of additive material  190  being introduced. 
     The cylindrical mixing container  102 , which is vertically oriented, provides a container for mixing or blending of a fluid  180  with an additive material  190 , which additive material  190  may be liquid or solid in form. Mixing or blending is accomplished by generating a vortex of the fluid  180  within the cylindrical mixing container  102 . The cylindrical mixing container  102  is defined by a mixing container top wall  104 , a mixing container bottom wall  106 , a mixing container sidewall  138 , and a longitudinal cylindrical mixing container axis  110 . The cylindrical mixing container  102  has a cylindrical mixing container outlet  114  which is positioned through the mixing container bottom wall  106  and which is aligned with the longitudinal cylindrical mixing container axis  110 . The cylindrical mixing container  102  likewise has a cylindrical mixing container liquid inlet  112  through the mixing container sidewall  138  which is bounded at a cylindrical mixing container inlet bottom  142  by the cylindrical mixing container bottom wall  106  and which is generally tangentially disposed toward an inner peripheral surface  150  of the cylindrical mixing container  102 . A top view of an embodiment of the apparatus when viewed downward from a plane A-A, provided in  FIG. 1  equivalent with the additive supply unit inlet  126 , is illustrated in  FIG. 2 , providing the cylindrical mixing container  102 , the mixing container sidewall  138 , the additive supply unit inlet  126 , the outer piping  118 , the additive supply unit  116 , the cylindrical mixing container liquid inlet  112 , the longitudinal cylindrical mixing container axis  110 , and the additive supply unit longitudinal axis  152 . One embodiment of the relative angle of the cylindrical mixing container liquid inlet  112  is illustrated in  FIG. 2 , showing the tangential alignment of the cylindrical mixing container liquid inlet  112  with respect to the mixing container sidewall  138  of cylindrical mixing container  102 , preferably at the mixing container bottom wall  106 . 
     Referring again to  FIG. 1 , addition of an additive material  190  is accomplished with the additive supply unit  116 . The additive  190  may contain one or more selected additives in a predetermined ratio. The additive supply unit  116  has an additive supply unit longitudinal axis  152  aligned and co-axial with the longitudinal cylindrical mixing container axis  110 , thus positing the additive supply unit in the center of the mixing container top wall  104 . The additive supply unit  116  includes an additive supply unit outer piping  118 , which has an additive supply unit outer piping top end  120  and an additive supply unit outer piping bottom end  122 . The additive supply unit  116  has one additive supply unit inlet  126  into the additive supply unit outer piping  118  at the additive supply unit outer piping top end  120 , but may have a plurality of additive supply unit inlets  126 . The additive supply unit  116  further has an additive supply unit shaft  128  slidably positioned within the additive supply unit outer piping  118  from the supply unit outer piping top end  120  to beyond the supply unit outer piping bottom end  122 . An additive supply unit collar  130  is positioned at the supply unit outer piping bottom end  122  to maintain the additive supply unit shaft  128  on the additive supply unit longitudinal axis  152 . An additive supply unit centrifugal supply disc  134  is affixed perpendicular to the additive supply unit shaft  128  at a bottom end of the additive supply unit shaft  128 . A motor  148  is coupled to the additive supply unit shaft  128 . Additionally, the additive supply unit  116  includes an isolating valve  146  which is adapted to terminate communication between the additive supply unit outer piping  118  and the cylindrical mixing container  102  and which is positioned above the mixing container top wall  104 . 
     Because the additive supply unit shaft  128  is slidably positioned within the additive supply unit outer piping  118 , it provides for vertical adjustment of the additive supply unit shaft  128  and therefore the additive supply unit centrifugal supply disc  134 . Vertical adjustment changes the clearance between the additive supply unit centrifugal supply disc  134  and the supply unit outer piping bottom end  122 , allowing for adjustment of the amount of additive  190  that can exit the additive supply unit outer piping  118  and enter the additive supply unit outer piping  118 . While the flow rate existing the additive supply unit outer piping  118  might be reduced to zero, the vertical adjustment of the additive supply unit shaft  128  is not intended primarily to function as a shut-off. A second linear actuator  174  may be coupled to the additive supply unit shaft  128  and adapted to retract the additive supply unit centrifugal supply disc  134  toward the supply unit outer piping bottom end  122  and to move the additive supply unit centrifugal supply disc  134  away from said supply unit outer piping bottom end  122 . 
     Because the additive supply unit centrifugal supply disc  134  is affixed to the additive supply unit shaft  128 , the additive supply unit centrifugal supply disc  134  rotates based on fixation to the additive supply unit shaft  128 . 
     The motor  148  may be of any type, such as electric or fluid and may be of fixed or variable-speed operation. Operation of the motor  148  may be controlled by a motor controller  164 . Moreover, the motor  148  may be coupled to the additive supply unit shaft  128  by any of various systems known in the art, but preferably is coupled so as to not to create a seal across the additive supply unit outer piping  118 . Coupling may be accomplished, for example, by use of a magnet couple between the motor  148  and the additive supply unit shaft  128 . A coupling which does not create a seal avoids the potential for creation of vacuum in the cylindrical mixing container  102  during retraction of the additive supply unit  116  from the cylindrical mixing container  102  from the second, deployed position depicted in  FIG. 1  to a first, ready position and avoids pressurization of the cylindrical mixing container  102  during deployment of the additive supply unit  116  into the cylindrical mixing container  102  from a first, ready position to the second, deployed position. 
     The linear actuator  124  is coupled to the additive supply unit  116 , such as by a shaft  117 , and is adapted to withdraw the additive supply unit  116  from the cylindrical mixing container  102  and above the isolating valve  146 . To the extent any additive  190  remains in the additive supply unit outer piping  118 , it is isolated from the contents of the cylindrical mixing container  102  due to the retraction of the additive supply unit  116  by the linear actuator  124  and by the closure of the isolating valve  146 . Operation of the linear actuator  124  may be controlled by a linear actuator controller  166 . Operation of the isolating valve  146  may be controlled by an isolating valve controller  172 . The isolating valve  146  may be of any type of valve providing a full closure, such as a ball valve. 
     The outlet line  153  is adapted for connection to the cylindrical mixing container outlet  114  and to an inlet  176  of a pump  154 . Preferably, the pump  154  provides a negative pressure (vacuum), and preferably of 5-10″, in the cylindrical mixing container  102  during operation. Operation of the pump  154  may be controlled by a pump controller  168 . 
     The fluid supply  156  is adapted for communication, via the pressure controller  184 , with the restricting valve  158 , which is adapted for communication with the cylindrical mixing container liquid inlet. In operation, this permits the supply of a liquid  180 , which may be contained in the fluid supply  156 , to the cylindrical mixing container  102  at a constant, or first, pressure. Operation of the restricting valve  158  may be controlled by a restricting valve controller  170 . 
     For operation, an additive  190  is introduced to the additive supply unit outer piping  118  at the additive supply unit inlet  126 . The additive supply unit inlet  126  can be perpendicular, at an angle (such as to form a “y”), or can intersect the additive supply unit outer piping  118  tangentially to provide a cyclonic effect of the additive  190  upon entering the additive supply unit outer piping  118 . An additive  190  may be composed of one or more selected additives. 
     Where desired, one or more fluid additive delivery nozzle  160  may be positioned inside the cylindrical mixing container  102  proximate the mixing container top wall  104 . Where used, a fluid additive controller  162  may be used to control a fluid additive valve  163  provision of a fluid additive  164  to flow from an associated fluid additive reservoir or supply  165  to the fluid delivery nozzle  160  and into the cylindrical mixing container  102 . More than one fluid additive  164 , and therefore more than one fluid delivery nozzle  160  and more than one associated fluid additive reservoir or supply  165  may be utilized. 
     Additionally, where an additive  190  is a liquid, a liquid-delivery tube  192  having a liquid-delivery tube first end  194  and a liquid-delivery tube second end  196  may be positioned in and through the outer piping  118  from its first end  194  to its second end  196 . to the other. As a result, the liquid-delivery tube  192  extends through the particle inlet  126  at the liquid-delivery tube first end  194  and terminates adjacent to the additive supply unit centrifugal supply disc  134  at the liquid-delivery tube second end  196 . This provides liquid communication rather than communication of the solid additive  190 . In operation, the liquid-delivery tube  192  is in fluid communication with a fluid additive reservoir or supply  165  of additive  190  so that a fluid additive  192  may be introduced rather than a solid additive  190 . 
     In operation, blending or mixing is accomplished according to the method illustrated in  FIG. 3 . 
     Referring to  FIG. 3 , in step  302 , the apparatus  100  is provided. 
     In step  304 , a vacuum is exerted on the cylindrical mixing container  102  by the pump  154 . Absent the exertion of a vacuum by pump  154 , it is not possible to force the fluid  180 , even if pressurized, into the cylindrical mixing container  102  and obtain a vortex. The combination of the pressurization of the fluid  180 , due to its relative position, and the vacuum in the cylindrical mixing container  102  draws the fluid  180  into the cylindrical mixing container and causes formation of the vortex. The extent of the vacuum may be adjusted by the restricting valve  158 . 
     In step  306 , the restricting valve  158  is opened to permit communication of the fluid  180  from the fluid supply  156  to the cylindrical mixing container liquid inlet  112  at the first pressure via the pressure controller  184 . A high energy vortex is formed by the fluid  180  in the cylindrical mixing container  102  due to the cylindrical construction of the cylindrical mixing container  102 , the lower position and relative angle of the cylindrical mixing container liquid inlet  112 , and the vacuum on the cylindrical mixing container  102  by the pump  154 . Thus, the cylindrical mixing container  102  receives the fluid  180  through the cylindrical mixing container liquid inlet  112  tangentially at the mixing container bottom wall  106 . The centrifugal force of the fluid  180  and the vacuum from the cylindrical mixing container outlet  114  cause the fluid  180  to form a vortex which eventually exits the cylindrical mixing container  102  through the cylindrical mixing container outlet  114  located in the mixing container bottom wall  106 . 
     In step  308 , the isolating valve  146  is opened. 
     In step  310 , the additive supply unit outer piping bottom end  122  is deployed through the isolating valve  146  into the cylindrical mixing container  102  by the linear actuator  124 , maintained in positive relative to the cylindrical mixing container  102  by a frame  125 , preferably so the additive supply unit centrifugal supply disc  134  is vertically centered in the cylindrical mixing container  102 . After the vortex is established in the cylindrical mixing container  102 , the additive supply unit  116  is transported down into the cylindrical mixing container  102  where feeding begins based on the speed and vertical adjustment of the additive supply unit centrifugal supply disc  134 . Since the centrifugal action of the additive supply unit centrifugal supply disc  134  projects the additive  190  horizontally from the additive supply unit centrifugal supply disc  134 , the additive  190  contacts the nearly vertical wall of fluid  180  within the vortex undergoes blending. Volume and velocity of additive  190  as projected into vortex is thus controlled, and not a result of a gravity feed. 
     In step  312 , the additive supply unit shaft  128  and the additive supply unit centrifugal supply disc  134  are caused to rotate by the motor  148 . 
     In step  314 , the additive material  190  is introduced into additive supply unit outer piping  118  at the additive supply unit inlet  126 . During operation, the rate of additive  190  delivered to the fluid  180  in the resulting high energy vortex in cylindrical mixing container  102  is a function of the speed of the motor  148 , and therefore the additive supply unit centrifugal supply disc  134 , the feed rate of additive  190  into the additive supply unit outer piping  118 , and the vertical position of the additive supply unit centrifugal supply disc  134  relative to the additive supply unit outer piping bottom end  122 . 
     In step  316 , the additive supply unit outer piping bottom end  122  is retracted out of the cylindrical mixing container  102 . Thus, when the blending cycle is complete, the additive supply unit centrifugal supply disc  134  stops, and the linear actuator  124  raises the additive supply unit  116  past the isolating valve  146 . 
     In step  318 , the isolating valve  146  is closed, isolating the moisture sensitive additive  190  from the moist environment. 
     While the present disclosure has been described in connection with presently preferred embodiments, it will be understood by those skilled in the art that it is not intended to limit the disclosure to those embodiments. It is therefore, contemplated that various alternative embodiments and modifications may be made to the disclosed embodiments without departing from the spirit and scope of the disclosure defined by the appended claims and equivalents thereof.