EA038757B1 - Mixing apparatus with stator and method - Google Patents

Abstract

A mixer and method for mixing are provided. The mixer includes a housing having a fluid inlet, an additive inlet, and an outlet, with the housing defining a mixing chamber in fluid communication with the fluid inlet, the additive inlet, and the outlet. The mixer also includes an impeller disposed in the mixing chamber, wherein, when rotated, the impeller draws fluid through the fluid inlet. The mixer also includes a slinger disposed in the mixing chamber and configured to receive the fluid from the impeller and to receive an additive from the additive inlet. When rotated, the slinger slings the fluid and the additive radially outwards. The mixer further includes a stator disposed at least partially around the slinger, with the stator including vanes spaced circumferentially apart so as to define flowpaths therebetween.

Description

State of the art

Mixers (sometimes alternatively called blenders) are typically used to disperse powdered chemicals in a fluid. One application of the mixers in downhole operations, for example, is to prepare a fracturing fluid for injection into a subterranean formation. Typically, the fracturing fluid contains gelling agents, powders, and other granular materials such as guar gum, which are first dispersed into the fluid using a mixer and subsequently hydrated, such as in tanks, to obtain the desired fluid viscosity.

Some mixers for powder and granular material include a centrifugal pump and ejector, or a centrifugal shear blender, or a high or low shear blender for dispersing the powder and granular material in a fluid (e.g., water). Typically, the fluid is pumped into the mixing chamber. In ejector mixers, the mixing chamber may be located near the throat of the converging nozzle so that the ejector draws the powdery substance into the mixing chamber through the Venturi effect. In blender mixers, the blender is located in the mixing chamber, and powdery substances and granules enter it, for example, by gravity. In either case, the materials, for example in the form of a dry powdery substance, are introduced into the mixing chamber and dispersed in the fluid. Various devices are used to prevent air from being sucked in during dispersion, or the entrained air can be removed downstream, for example, using a hydrocyclone or another type of air separator. The fluid mixture can then be directed to downstream equipment for further hydration.

One problem with dispersing powdered additional components, such as gelling agents, is that the powdered substances may have a tendency to clump together, sometimes called fisheyes. Powdered substances can have cohesive properties that form partially hydrogenated beads, for example, as a dry powdery substance surrounded by a crust of partially hydrated powdery substance. This crust prevents the dry powdery substance within them from being hydrated, which results in the fish eye being stably retained in the fluid instead of evenly dispersing the powdery substance.

Accordingly, insufficient mixing can affect downstream operations. In addition, there is an additional risk of material build-up and / or adhesion, for example, in different system throats if the materials are not sufficiently wetted at the point of entry into the mixer.

Accordingly, in some cases, pre-wetting may be used to reduce the risk of such lumps forming. Pre-wetters typically supply fluid to a powder feed point upstream of the mixing point. However, pre-wetting devices require a separate pump to supply fluid to the powder before entering the mixing chamber. Thus, additional pumping equipment (ie, centrifugal pumps delivering fluid for pre-wetting) can add complexity to the overall system, adding costs, maintenance, and potential failures. In addition, various pieces of equipment can limit the range of flow rates achievable by the system, limiting the number of applications for which a particular mixer size or configuration is suitable.

Disclosure of the essence of the invention

Embodiments of the present invention may include a mixer that includes an impeller, a deflector, and a flush channel. The impeller and deflector can be arranged in a back-to-back configuration and are part of the impeller / deflector assembly and can be rotated by the shaft to which they are attached. The impeller draws fluid into the mixing chamber through the fluid inlet, injects the fluid and pushes it down and out. The fluid is then directed towards the reflector. The deflector can, through the additional component inlet, receive additional components to be mixed with the fluid, and can push the additional components radially outward to mix with the fluid.

The flush channel may include an opening in the mixing chamber in the relatively high pressure region of the mixing chamber, such as near the impeller. The region of relatively high pressure can also be an area of relatively clean fluid (eg, with a low concentration of additional components) that can be vented through the flush channel. The flush passage may extend into an additional component guiding structure (eg, a cone or other type of hopper) through which the additional components enter the additional component inlet. Due to the fluid pressure in the mixing chamber created by the impeller, the flush channel can direct relatively clean fluid from the mixing chamber to the additional component guiding structure so as to pre-wet the additional component, thereby reducing the likelihood of sticking ...

While the above summary has described one or more aspects of the present invention, these and other aspects will be discussed in more detail with reference to the following drawings and detailed description. Accordingly, this summary is not intended to limit the present invention.

Brief Description of Drawings

The accompanying drawings, which are included in this description and are an integral part of this description, illustrate one of the embodiments of the ideas of the present invention and together with the description serve to explain the principles of the ideas of the present invention. In these figures:

in fig. 1 is a schematic diagram of a mixing system according to one embodiment;

in fig. 2 is an exploded perspective view of a mixer in accordance with one embodiment;

in fig. 3 is an enlarged view of a portion of the stator of the mixer of FIG. 2 corresponding to one of the embodiments;

in fig. 4 is a perspective view of a mixer section according to one embodiment;

in fig. 5 is a cross-sectional side view of a mixer in accordance with one embodiment;

in fig. 6 is a schematic side view of a mixer in accordance with one embodiment;

in fig. 7 is a graph showing pressure and fluid purity versus radius in accordance with one embodiment;

in fig. 8 is a perspective view of a mixer impeller / reflector assembly in accordance with one embodiment;

in fig. 9 is another perspective view of an impeller / reflector assembly in accordance with one embodiment;

in fig. 10 is a perspective view of a reflector of a mixer in accordance with one embodiment;

in fig. 11 is a perspective view of a mixer stator according to one embodiment;

in fig. 12 is a cross-sectional side view of a mixer according to another embodiment;

in fig. 13 is a flow diagram of a method for dispersing an additional component in a fluid in accordance with an embodiment.

It should be noted that some of the details in the figures have been simplified and drawn to facilitate understanding of the embodiments and not to accurately convey design, details of construction, and scale.

Implementation of the invention

The following is a detailed description of embodiments of the present invention, examples of which are illustrated in the accompanying drawings. In the drawings and the following description, like reference numbers have been used to indicate like elements where appropriate. It should be appreciated that the following description does not exhaust all possible examples, but is purely illustrative.

FIG. 1 shows a schematic diagram of a mixing system 100 in accordance with one embodiment. Typically, the mixing system 100 may include a process fluid source 102, a mixer 104, and downstream equipment 106, among other potential components. Process fluid source 102 may be (or may contain) a reservoir of water, an aqueous solution with a suitable acidity (pH) and / or any other type of solution, or any substantially liquid substance. In addition, the source 102 may include one or more pumps for supplying fluid to the mixer 104, or may be connected to them; however, in other embodiments, in which, for example, the mixer 104 is pumping, such pumps may be omitted. Downstream equipment 106 may include any number of hydration tanks, separators, other mixers / mixing systems, pumps, etc. to convert the slurry exiting the mixer 104 into a fluid of the desired viscosity and / or composition.

As schematically depicted in the figure, the mixer 104 may include a housing 107 as well as a fluid inlet 108 and an additional component inlet 110 extending through the housing 107. The fluid inlet 108 may be connected to a fluid source 102. whose medium and can be configured to receive a fluid (i.e., process fluid) therefrom. The accessory inlet 110 may typically include an accessory receiving structure 111, which can / may include a cone, chamber, bowl, hopper, or the like, with an interior surface 115 configured to receive an accessory 113 , which can be a dry powdery substance, and guiding it into the housing 107, for example, by gravity.

It will be appreciated that any dry, partially dry, crystallized, suspended, liquid or granular and / or pouched accessory can be dispersed in or otherwise mixed with the fluid by means of mixer 104 through the accessory inlet 110, schematically depicted in figure. In addition, as will be described in more detail below, additional components received through the additional component inlet 110 may be pre-wetted in a partial slurry, for example, to avoid the formation of fish eyes (clumps) and / or any build-up of material. In particular, in various embodiments, the mixer 104 may be configured to be used when mixing sand, guar, other powdered substances, etc. with a fluid medium. In addition, in some cases, the mixer 104 can be configured to be used as a chopper that can break fibers, bags containing powders, granules, etc., to disperse their contents in a fluid. In at least one instance, mixer 104 may be configured to be used to prepare a gel for use in fracturing operations, such as in a wellbore; however, in accordance with the present invention, the number of different applications of the mixer 104 is not limited.

The mixer 104 may also include an impeller / deflector assembly 112 that can be driven by a shaft 114. The housing 107 may form a mixing chamber 118 that communicates with the inlets 108, 110. The impeller / deflector assembly 112 may be located in the mixing chamber 118. Rotating impeller / deflector assembly 112 allows fluid to be pumped from source 102 through mixing chamber 118 and into outlet 121.

As shown in the figure, shaft 114 may extend upwardly through inlet 110 and out of structure 111 to receive an additional component; however, this is just one of many possible examples. In another example, the impeller / deflector assembly 112 may extend downwardly through the bottom of housing 116, may have a magnetic actuator located within the mixing chamber 118, or may otherwise be located in the housing 107. Shaft 114 may be coupled to the actuator assembly 112. wheel / deflector so that when the shaft 114 rotates, the impeller / deflector assembly 112 rotates. In some cases, the shaft 114 can be directly connected to the impeller / deflector assembly 112, for example, using a bolt; however, in other cases, gears, transmissions, other speed varying devices, or couplings may be used to connect the shaft 114 to the impeller / deflector assembly 112.

The mixer 104 may also include a stator 120, which may be in the form of a ring, arcuate, etc., which may be positioned around the impeller / deflector assembly 112, as will be described in more detail below. In addition, the mixer 104 may include an outlet 121 and a flush channel 122. A slurry formed from a combination of a complementary component received through an additional component inlet 110 and a fluid received through a fluid inlet 108 may exit through the outlet 121. ... Outlet 121 may direct slurry into one or more conduits 124 that may carry fluid to downstream equipment 106.

One end of the flush passage 122 may be connected to an area of the mixing chamber 118 that is located adjacent to the impeller / deflector assembly 112, and the other end to a structure 111 for receiving an additional component. Accordingly, the flush channel 122 can draw process fluid from the mixing chamber 118 in a relatively high pressure region and supply it to the inner wall of the structure 111 to receive an additional component where the pressure can be reduced (eg, equal to the ambient pressure). In addition to being vented through the flush port 122 at a relatively high pressure, fluid may be relatively clean (i.e., relatively low in additive content, as described below) in order to pre-fluidize the structure 111 to receive additional component and avoid clumping of additional components. In some cases, flush port 122 may provide fluid pre-wetting without requiring additional inflating devices (other than the inflating mechanism that provides impeller / deflector assembly 112) or additional fluid sources or piping from source 102. In other examples, in addition booster pumps, etc. may be provided to drain fluid from mixing chamber 118 or instead.

FIG. 2 is an exploded perspective view of a mixer 104 corresponding to one of

- 3,038757 embodiments. As noted above, mixer 104 may include a housing 107, which is depicted in FIG. 2 as formed from two parts: a first or upper body portion 126 and a second or lower body portion 128. The upper and lower body parts 126, 128 can be connected to each other, for example, using bolts, brackets, other fasteners, adhesive joints, welded joints, etc., to form a mixing chamber 118 between them (Fig. 1) ... In one particular example, the lower body portion 128 may be a blending region 130 and the upper body 126 may be a blending region 132 (shown in dashed lines), which may typically be aligned. Mixing regions 130, 132 may together form a mixing chamber 118 (FIG. 1) in which impeller / deflector assembly 112 and stator 120 may be located. The lower housing portion 128 may also include an interior surface 139, for example defining the lower portion of region 130 mixing. It will be appreciated that it is contemplated that various configurations of housing 107 can be applied, including one-piece and segmented embodiments, door embodiments, and so on.

The upper body portion 126 may be coupled to the structure 111 for receiving an additional component and may include an inlet 110 for the additional component. The lower body portion 128 may include a fluid inlet 108 that can pass through an opening 133, which is typically located in the center of the lower body portion 128. In one embodiment, an opening 133 may be formed in the inner surface 139. In addition, the outlet 121 may extend from the mixing region 130, for example, may include a substantially tangential conduit 135 extending from the opening 137 which communicates with a mixing area 130.

The impeller / deflector assembly 112 located in the mixing chamber 118 may include a deflector 134 and an impeller 136. The deflector 134 and impeller 136 may have inlet ends 134-1, 136-1, respectively, and rear surfaces 134-2, 136-2 respectively. Each of the inlet ends 134-1, 136-1 may be open (as shown in the figure) or at least partially covered by a shroud that defines an inlet in the radial interior of the reflector 134 and / or impeller 136. In addition, the inlet the ends 134-1, 136-1 may be oriented in opposite directions, for example, to receive fluid and / or dry components. The rear surfaces 134-2, 136-2 may be located adjacent to each other and, for example, connected to each other such that, for example, the impeller 136 and the deflector 134 are located in a rear-to-rear configuration.

In one embodiment, the inlet end 134-1 of the reflector 134 may face the inlet 110 for an additional component (e.g., a structure 111 for receiving the additional component), and the inlet end 136-1 of the impeller 136 may face the inlet 108 for fluid (eg, port 133) as shown in the figure. For example, the inlet end 136-1 of the impeller 136 may face an inner surface 139 with an opening 133 formed on the inner surface 139 that is aligned with the radial center of the impeller 136.

Accordingly, as shown in the figure, the reflector 134 may face upward as determined by the direction in which the inlet ends 134-1, 136-1 are oriented, but in other embodiments it may face downward or laterally. Likewise, the impeller 136 may be facing downward as shown in the figure, but in other embodiments it may be facing upward or laterally. In addition, both the deflector 134 and the impeller 136 may have a radius, the radius of the deflector 134 being greater than the radius of the impeller 136. The radii of the deflector 134 and the impeller 136 may be dependent on each other so that the boundary position can be controlled. fluid-air, as will be described in more detail below.

The reflector 134 may also have the saucer-like shape shown in the figure, i.e., it is generally formed shallow (or flat) in the middle with arcuate sides and an inlet end 134-1. In one embodiment, the sides may be formed, for example, in the form of a torus or a portion of a torus that extends around the middle portion of the reflector 134. In another embodiment, the reflector 134 may be cup-shaped (eg, typically a portion of a sphere). In addition, the deflector 134 may include deflector blades 138 at the inlet end 134-1. The number of blades 138 can be selected from the range of about two blades to about 20 blades, for example, it can be about nine blades. In some cases, the vanes 138 may be curved around the circumference, extending radially outward from the shaft 114, but in other cases, the vanes 138 may be straight, as shown in the figure. The deflector 134 may be configured, when rotated, to push the fluid and / or dry additional components received from the inlet 110 radially outward as a result of interaction with the blades 138 and upward (as shown in the figure), for example, due to reflector shape 134.

Although not visible in FIG. 2, the impeller 136 may also include a plurality of vanes at the inlet end 136-1, which may typically be aligned with bore 133. When the shaft 114 is pivoted, the impeller vanes may draw fluid through the aperture 133 of the fluid inlet 108. medium, and then push it downward and radially outward. Thus, a region of relative high pressure can develop between the bottom of the housing 128 and the impeller 136, which can cause the fluid to move around the circumference of the mixing chamber 118 and towards the deflector 134.

The flush passage 122 may include an opening 140 formed in the lower body portion 128 adjacent to this high pressure region. For example, an opening 140 may be formed on the inner surface 139 at a location between the outer radial contour of the impeller 136 and the opening 133 of the inlet 110. In other embodiments, the opening 140 may be located on the inner surface 139 and radially outward from the impeller 136 and / or elsewhere in mixing chamber 118. Flush passage 122 may also include conduit 142, which may be one or more of pipes, tubes, hoses, flow restrictors, check valves, and so on. or contain them. Conduit 142 may be connected to cone inlet 144, which is positioned, for example, substantially tangential to complementary component structure 111, such that fluid is pumped from port 140 through conduit 142 through cone inlet 144 and into structure 111 to receive an additional component. The fluid can then move in a generally helical path along the interior of the structure 111 to receive the additional component until it enters the deflector 134 through the additional component inlet 110. Thus, the fluid entering through the cone inlet 144, typically can form a fluid wall along the interior surface 115 of structure 111 to receive an additional component.

In at least one particular embodiment, a pressure drop may occur between the impeller 136 and the lower housing portion 128, with the pressure in the fluid increasing as it moves radially outward from the orifice 133. In addition, another differential may occur in this area. associated with the concentration of additional components in the fluid, and the concentration of additional components increases as it moves outward in the radial direction. In some cases, a high head and low concentration may be required to deliver a relatively clean fluid flow through the flush port 122 created by the impeller / deflector assembly 112. Accordingly, the opening 140 of the flush channel 122 may be positioned at a point along this region such that an optimal ratio between the fluid head and the concentration of additional components in the fluid entering the flush channel 122 can be achieved. Further details regarding this optimum ratio are provided below. ...

The stator 120 may be a shear ring that may be positioned within the mixing chamber 118 around the circumference of the radial outer side of the impeller / deflector assembly 112 (FIG. 1). In one example, the stator 120 may be connected to the upper housing portion 126, for example, using bolts, other fasteners, adhesives, welds, and so on.

FIG. 3 is an enlarged sectional view of stator 120 of FIG. 2 in accordance with one embodiment. As shown in FIG. 2 and 3, stator 120 may include first and second annular portions 146, 148 that may be stacked to form stator 120. Stator 120 may be held substantially stationary relative to rotatable impeller / reflector assembly 112, for example, by attaching to the top of the body 126. In another embodiment, the stator 120 may be supported by and rotated with the impeller / deflector assembly 112. In any of the examples, the stator 120 may move along the inlet end 134-1 of the reflector 134 or may be separated from it.

The first annular portion 146 may be configured to minimize flow blockage. As shown in the figure, in some cases, the first annular portion 146 may include a band 150 and cross members 152 that define relatively wide slots 154 to allow fluid flow to flow relatively freely therethrough. In other embodiments, the first annular portion 146 may not include a band 150, as will be described in more detail below.

While the first annular portion 146 can minimize blockage of flow, the second annular portion 148 can be configured to maximize flow shear to allow for turbulent mixing and thus can comprise a series of stator blades 156 that are close to each other around the circumference. stator 120. Between the stator blades 156 there may be narrow ducts 158; wherein the sum of the areas of the duct 158 may be less than the sum of the areas of the stator blades 156. In various embodiments, the ratio of the cross-sectional area of the stator vane 156 (i.e., the area that obstructs flow) to the area of the ducts 158 can be from about 1: 2 to about 4: 1, such as about 1.5: 1. In addition, the area of each of the stator vanes 156 may be greater than the area of each of the ducts 158. In addition, the stator vanes 156 may be located at any angle of inclination with respect to the circumference of the stator 120. For example, the stator vanes 156 may be roughly 5 038757 are oriented straight in the radial direction in the opposite direction of rotation (for example, to increase shear), or in the direction of rotation. In the example shown in FIG. 2 (as well as in Fig. 3 and

4, described below), the stator blades 156 may have a shroud 157 that separates the sections 146, 148. In other embodiments, which will be described in more detail below, the stator 120 may not include one of the shrouds 150, 157, or may not contain any from bandages.

FIG. 4 is a perspective view of a section of a mixer 104 according to one embodiment. FIG. 5 is a cross-sectional side view of a mixer 104 with a schematic flush passage 122, in accordance with one embodiment. As shown in FIG. 4 and 5, shaft 114 extends through the accessory inlet 110 and is coupled to the impeller / deflector assembly 112. The impeller 136 is oriented towards the opening 133 such that the vanes 160 of the impeller 136 draw in fluid through the opening 133 of the inlet 108.

With reference to FIG. 4 and 5 in FIG. 6 is a schematic, simplified cross-sectional view of a mixer 104 according to one embodiment. As shown in the figure, the impeller 136 can draw fluid upward from the inner surface 139 and then push it down (towards the inner surface 139) and radially outward. The fluid can then move up the mixing chamber 118, for example along the outer wall of the housing 107 to the top of the upper housing portion 126 where it can pivot radially inward. The fluid may then pass through the first annular portion 146 of the stator 120 to the deflector 134, and then be pushed radially outward and also upwardly back to the top portion 126 of the housing. Due to this, turbulent vortex can occur, as well as a hydrodynamically stable interface between fluid and air, which usually appears as an annular air-fluid interface or ring 161 (Fig. 5) between the shank 138-1 and the end 138-2 of the blades 138 reflectors. Thus, the deflector 134 tends to create a vortex separation effect, thereby preventing the air entering through the inlet 110 from being sucked into the fluid from the impeller 136.

In this case, additional components 113, which are poured or otherwise received through the inlet channel 110, for example, are moved by gravity, but they can also move due to pressure drops, evacuation, the use of blowers, pumps, etc. Additional components then enter the inlet end of the reflector 134, such as the air side of the air-fluid interface. The additional components collide with the blades 138 and are projected outward in a radial direction into the fluid from the impeller 136, thereby creating a tangential component of the velocity of movement of the fluid and dry additional components. The circumferentially and radially movable dry complementary components and fluid then pass through the second annular portion 148 of the stator 120, where the combination undergoes a strong shear when interacting with the stator vanes 156, passing through the ducts 158. Shear created by interaction with the vanes 138 and the stator vanes 156 and the turbulent flow generated by the impeller / deflector assembly 112 allow for substantially uniform dispersion of the additional components in the fluid from the source 102, resulting in a slurry.

In particular, the first section 146 of the stator 120 is located at a small radial distance from the blades 138 of the reflector (for example, in a radial direction outward from them) such that the slurry mixture of additional components 113 (for example, powdered chemicals) and fluid, projected outward by the blades 136 of the reflector, at the first stage is shifted in the gap due to the relative movement of the blades 134 and the stator blades 156. A second stage of shearing of the slurry then begins as it is between adjacent stator vanes 156 and is pushed radially outward through the ducts 158 by the action of the deflector 134. In addition, the sudden expansion of the flow cross-sectional area radially outward from the stator 120 results in a cavitation vacuum. which further aids in mixing. Thus, during operation, the mixer 104 provides a two-stage high shear mixing and zonal cavitation vacuum. The second section 148 of stator 120 may have substantially large openings and be positioned above the blades of the reflector such that it allows fluid to enter the reflector 134 through slots 154 or otherwise minimizes blockage of flow through the stator 120.

The slurry can be repeatedly subjected to this agitation by swirling it backward through portions of the deflector 134 to further disperse additional components into the fluid, and eventually the slurry reaches the outlet 121 shown in FIG. 5. The slurry reaching the outlet 121 is directed from the mixing chamber 118 to, for example, downstream equipment 106 (FIG. 1) for further hydration, preparation for use, processing, etc. In addition, as schematically shown in FIG. 5, the mixer 104 can also perform an automatically controlled pre-wetting by means of the flush channel 122. The opening 140 can be located on the inner surface 139 of the lower body portion 128, for example, radially inward or outward from the outer radial contour of the impeller 136. This location may be a high pressure region in mixing chamber 118 where fluid is cleaner than fluid elsewhere in mixing chamber 118, such as closer to outlet 121 and / or baffle 134.

Discharged relatively clean fluid entering through opening 140 may pass through flush passage 122 into structure 111 to receive additional component. The pre-wetting fluid can then, for example, by gravity flow along the inner surface of the complementary component 111 through the inlet 110 and back to the reflector 134. Thus, the additional components can be moved along the 111 to receive the complementary component in the direction reflector 134, while simultaneously pre-wetting them. This minimizes clumping at the surface of the structure 111 to receive the additional component.

FIG. 7 is a graph of pressure and fluid purity in mixing chamber 118 versus radius from the center of bore 133, which is aligned with the center of impeller 136. As shown, when moving radially outward with respect to impeller 136, pressure can vary from atmospheric pressure. (i.e., zero psig) to the maximum inflation pressure generated by the impeller 136. The relationship between the radial position and the head may be substantially exponential until the specified position reaches the radial contour of the impeller 136.

Conversely, purity, i.e. the reciprocal of the concentration of additional components in the fluid, or in other words, the purity of the fluid, may decrease as it moves radially outward, where fluid entering through inlet 108 mixes with the additional components. Accordingly, the retraction area 141 can be calculated by determining the optimal relationship between the head and the purity of the fluid discharged into the flush channel 122 through the opening 140.

In addition, the flow rate of relatively clean fluid through the flush channel 122 can be controlled, for example, by adjusting the location or size of the opening 140, conduit 142, and / or cone inlet 144 with respect to the head created by the impeller 136. With a known pressure drop across the flush channel 122 may allow such adjustment to optimize the amount of fluid flowing through flush channel 122. In addition, flush channel 122 may include one or more flow control devices that also control the flow through flush channel 122.

FIG. 8 is a perspective view of an impeller / reflector assembly 112 and a stator 120 in one embodiment. Stator 120 may include the first and second annular portions 146, 148 described above. However, the second annular portion 148 may include a plurality of cross members 170 that may extend upwardly from the first annular portion 146, but may not include a band. For example, the cross members 170 may be coupled to the upper body 126 (FIG. 2). The crossbeams 170 can be of any shape, including cylindrical, aerodynamic, etc., and can be spaced apart from each other, which defines wide channels between them. Accordingly, the second annular portion 148 can be configured to minimize blockage of the flow therethrough.

In addition, as shown in the figure, the stator vanes 156 can be angled with respect to the circumference of the stator 120, for example, counteracting rotation to maximize shear. Likewise, the deflector vanes 138 can be circumferentially curved, for example, to facilitate pushing the fluid and additional components radially outward and thus shear by the tangential velocity component.

The stator 120 shown in FIG. 8, can act as a diffuser. In at least one embodiment, the stator vanes 156 shown in the figure may be oriented to allow pressure build-up and / or may facilitate mixing of air into the slurry, for example during foaming operations.

FIG. 9 is another perspective view of the impeller / deflector assembly 112 illustrating the inlet end 136-1 of the impeller 136 according to one embodiment. As shown in the figure, blades 160 of impeller 136, which may be curved, straight, or any other suitable geometry, may draw fluid upward and then expel it radially outward into mixing chamber 118 (see, for example, Fig. 3). It will be appreciated that impeller 136 may be capable of high speed (eg, between about 300 rpm and about 20,000 rpm) and may be capable of pumping between about 5 psi. inch (about 34 kPa) and about 150 psi. inch (approximately 1000 kPa), for example approximately 60 psi. inch (approximately 414 kPa).

FIG. 10 is a perspective view of another reflector 200 of mixer 104 corresponding to one embodiment. In some cases, the rotor blades (eg, blades 138 shown in FIG. 1) may exhibit dispersion beyond the desired degree, such as for specialty particles such as an encapsulated gel breaker. In some cases, this can lead to the premature release of chemicals into the fluid. Accordingly, in one embodiment, the reflector 200 can provide a low or controlled shear dispersion to handle such delicate chemicals that are prone to damage or otherwise become unsuitable for use in more intense reflector embodiments. In particular, the deflector 200 can be relatively gradual in dispersion when using mainly concentric annular discs 202 that are mounted one on top of the other upward from the hub 204. The annular disc 202-1 located closest to the hub 204 may have a smaller inner diameter than an adjacent annular disc 202-2, which in turn may have a smaller inner diameter than annular disc 202-3. This relationship between adjacent discs 202 can be repeated further away from hub 204, thus forming an inlet face 205 of reflector 200 through which fluid and / or additional components can be received and pushed outward. It should be understood that any number of annular discs 202 may be used.

In one embodiment, the discs 202 may be separated by vanes 206 to form narrow ducts between the discs 202. The vanes 206 may have slots, one at each of the annular disks 202, into which the annular disks 202 can enter and in which they can be connected to the vanes 206. Accordingly, narrow channels can extend radially outward, for example, blocked in the radial direction only by narrow vanes 206. In other embodiments, individual vanes may extend between each pair of adjacent discs 202 instead of vanes 206 that extend through, or in addition to, the entire set of discs 202. Additionally, in some embodiments, the vanes 206 may be coupled to one or more subgroups of the total number of discs 202. In some cases, the vanes 206 may be omitted, with spaced discs 202 connected in any other suitable manner.

The large surface area of the annular discs 202 that define the ducts and the narrowness of the ducts can lead to shear and turbulent fluid flow therein. Such shear can have the same effect as the deflector 134 and stator 120 discussed above, and can help to disperse the dry additional components into the fluid, which is pushed radially outward through them, while minimizing the impact of the blades 204. which can damage delicate material. In some cases, due to the shear created by the reflector 200, the stator 120 may be eliminated; however, in other cases, the shear effect of stator 120 and reflector 200 may be combined.

FIG. 11 is a perspective view of an unshielded stator 300 according to one embodiment. As shown in the figure, the stator 300 includes first and second annular portions 302, 304, both of which, as shown in the figure, can be unshielded. The first annular portion 302 may include a base 306 and a series of vanes 308 extending upwardly from the base 306 and spaced around the circumference of the first annular portion 302. Passages 310 are formed between adjacent vanes 308.

If the stator 300 does not include a shroud, the tops of the ducts 310 may open into the second annular portion 304 of the stator 120. The second annular portion 304 may include protrusions 312 extending upwardly from the first annular portion 302. The protrusions 312 may be thicker in the circumferential direction, than the vanes 308, for example, each of them overlaps two vanes 308 and one of the ducts 310; however, vanes 308 and projections 312 of any relative size may be used. The use of a no-shroud configuration can minimize blockage of flow from the impeller 136, increasing the performance of the mixer 104.

FIG. 12 shows a cross-sectional side view of a mixer 104 according to another embodiment. The embodiment shown in FIG. 12 may be broadly similar to the embodiment of mixer 104 shown in one or more of FIGS. 1-8, where the same components are indicated with the same reference numbers, and duplicate descriptions are omitted. However, the mixer 104 shown in FIG. 12 may include a stator 400 that is integral with the housing 107, such as the lower housing portion 128. Accordingly, the stator 400 can be radially displaced with respect to the impeller / deflector assembly 112 and can surround it, with the outlet 121 disposed radially outward of the stator 400. Supporting the stator 400 with the lower housing portion 128 (and / or being integrally formed ) can cause the impeller / deflector assembly 112 to rotate with low friction because the stator 400 and impeller / deflector assembly 112 may not be in contact with each other. In another embodiment, to achieve a similar effect, the stator 400 may be suspended from and / or integral with the upper housing portion 126.

- 8 038757

This embodiment of the mixer 104 in some cases allows all or substantially all of the incoming fluid to be mixed with the additional chemical before it exits the mixer 104. For example, when mixing cement, the mixer 104 may uniformly mix the particulate matter so that to avoid dependence on turbulence in the tube downstream of the mixer 104 to effect such mixing.

Stator 400, like stator 120, may or may not have a shroud and may contain two or more annular portions (eg, one for blocking low flow and one for blocking high flow). However, the stator 400 can be configured to receive substantially all of the fluid flow from a possible volume of fluid, which can improve the mixing of the dry matter. Such an embodiment of the mixer 104 using the stator 400 may be suitable for dispersing a powdery substance into a highly viscous fluid, as well as a high volume fraction of the powdery substance in the mixture, for example when preparing a cement mixture. In addition, although not shown, the mixer 104 according to the embodiments shown in FIGS. 12 may include a flushing channel 122 such as described above.

FIG. 13 shows a flow diagram of a method 1000 for dispersing an additional component, such as a dry additional component (eg, a powdery substance, granules, etc.) in a fluid, in accordance with an embodiment. Method 1000 may be performed using one or more embodiments of mixing system 100 and / or mixer 104 and is thus described herein with reference to them. However, it should be understood that method 1000 is not limited to any particular design unless otherwise indicated herein.

Method 1000 can include supplying fluid to mixing chamber 118 of mixer 104 through fluid inlet 108 (step 1002). For example, mixing chamber 118 may be located within housing 107, which may have a fluid inlet 108 that receives fluid from source 102. In addition, method 1000 may include feeding additional component into mixing chamber 118 through inlet 110 to additional component (block 1004). Material supplied in step 1004 may be propelled by gravity, such as pouring an additional component into the structure 111 to receive an additional component in the inlet 110 for the additional component, although other methods of supplying the additional component are contemplated.

In addition, method 1000 may include rotating the impeller / deflector assembly 112 located within mixing chamber 118 (block 1006). When rotated, the impeller / deflector assembly 112 can draw fluid from the fluid inlet 108 (e.g., upward) and radially outward, for example, by the action of the impeller 136, the inlet end 136-1 of which is located near the inner surface 139 Rotation of the impeller / deflector assembly 112 may further expel fluid, such as from the impeller 136, along with the accessory received through the accessory inlet 110, radially outward. In one example, the outward pushing can be performed by the deflector 134 of the impeller / deflector assembly 112, which may include blades 138 and / or discs 202. In addition, the deflector 134 may have an inlet end 134-1 that may, for example, be oriented in the direction inlet 110 for additional component. When the additional component is fed through the additional component inlet 110, the additional component may collide with the vanes 138 and / or discs 202 and move outward in a radial direction.

The use of a combination of impeller 136 and deflector 134, for example, in a back-to-back configuration, can cause a ring in the deflector 134 defined by a hydrodynamically stable fluid-air interface. For example, this boundary may be radially present between the hub 138-1 and the end 138-2 of the vanes 138 of the deflector 134. Pushing the additional component (as well as the fluid from the impeller 136) radially outward by the deflector 134 may cause the additional component to cross air-fluid interface, and thus at least partially dispersing it in the fluid to form a suspension. In some cases, the operation of the impeller / deflector assembly 112 can create a hydrodynamically stable ring that forms a fluid-air interface thereby preventing air from being sucked into the fluid. However, in some cases, air may be deliberately introduced into the mixture, for example, during foaming operations, for example, using the stator 120 of FIG. eight.

The additional component can be further dispersed in the fluid (to increase the homogenization of the slurry) by passing the slurry through the stator 120 (step 1008). Various embodiments of stator 120 have been described above, for example, with first and second annular portions 146, 148 provided to minimize and maximize fluid shear, respectively. Typically, stator 120 may include a plurality of blades 156 defining flow paths between

- 9 038757 them, through which the suspension enters. The interaction of the swirling turbulent flow of the slurry with the stator vanes 156 can increase the shear of the fluid, thereby increasing the mixing efficiency of the mixer 104. After mixing to the desired extent, the slurry with a certain concentration of additional components can be pushed out of the mixer 104 (step 1010) through an outlet 121 that may be radially outwardly relative to the impeller / deflector assembly 112.

In addition, method 1000 may include, for example, pivoting of the impeller / deflector assembly 112 at 1006, a portion of the fluid or slurry (eg, at a relatively low concentration compared to flow through outlet 121) into flush channel 122, and into the accessory inlet 110 to pre-wet the accessory (step 1012). For example, the flush channel 122 can include an opening 140 that can be positioned and / or sized to receive a slurry with a predetermined (eg, minimized) concentration of additional components at a predetermined (eg, maximized) mixing chamber pressure. 118. Sizing the flushing channel 122, placing its opening 140 and / or using devices to control the flow rate in the flushing channel 122, etc. may allow the amount and composition of fluid that flows through the flush channel 122 to be controlled.

It should be understood that terms indicating a direction or orientation, such as above, below, up, down, above, below, on the side, etc., are used solely for convenience to indicate the relative positioning of components depicted in the various figures with respect to each other. to friend. However, those of ordinary skill in the art will appreciate that these terms are not intended to limit mixer 104 to any particular orientation.

In addition, although the teachings of the present invention have been illustrated in relation to one or more variations, changes and / or modifications may be suggested to the illustrated examples without departing from the spirit and scope of the appended claims. In addition, although a particular feature of the teachings of the present invention could be disclosed in relation to only one of several implementations, such a feature may be combined with one or more other features of other implementations that may be desirable and preferred for any given or specific function. In addition, in cases where the terms including, includes, having, has, with, or variations thereof are used in the detailed description and in the claims, such terms are intended to mean the inclusion in the method of a similar term containing. In addition, in the discussion and in the claims, the term “approximately” indicates that the recited value may be slightly changed, and this change is possible to the extent that it does not lead to a discrepancy between the method or design of the illustrated embodiment. Finally, the term illustrative indicates that the description is given as an example, and does not imply that it is the most appropriate.

Other embodiments of the ideas of the present invention will become apparent to those skilled in the art upon studying the description and practice of the ideas of the present invention disclosed in this document. The description and examples are intended to be illustrative only, and the true scope and spirit of the teachings of the present invention are set forth in the appended claims.

Claims (14)

CLAIM 1. A mixer containing a shaft for driving the mixer, the shaft is located in the housing and extends through it, and the housing contains a fluid inlet adjacent to one axial end of the shaft, an inlet for additional components adjacent to the opposite axial end of the shaft and a tangential outlet located between the fluid inlet and the accessory inlet, the housing defining a mixing chamber that is in fluid communication with the fluid inlet, the accessory inlet and the outlet; an impeller disposed on a shaft in the mixing chamber, when the impeller rotates, draws fluid through the fluid inlet axially; a reflector located on a shaft in the mixing chamber and configured to receive a fluid from the impeller and receive an additional component from an inlet for an additional component in an axial direction opposite to the axial direction of the fluid, and when rotated, the reflector pushes the fluid and the additional component radially directed outward towards the tangential outlet of the housing; and a shear annular stator disposed at least partially around the circumference of the reflector, wherein the stator comprises first and second annular parts mounted one on top of the other, and blades spaced circumferentially from each other so that between them are formed - 10 038757 ducts; moreover, the reflector (134, 200) and the impeller (136) have inlet ends (134-1, 136-1), respectively, while the reflector (134, 200) and the impeller (136) are located in the housing in the configuration back side to back side so that the impeller (136) creates a fluid flow passing radially outward from the reflector (134, 200) up into the mixing chamber (118), and then radially inward towards the center of the reflector (134, 200) ... 2. The mixer according to claim 1, further comprising a shaft connected to the reflector and the impeller for rotating the reflector and the impeller. 3. The mixer according to claim 1, characterized in that the stator is radially offset relative to the blades of the reflector so that there is a gap between them. 4. The mixer according to claim 1, characterized in that the stator comprises a first annular part defining the area of the first duct and a second annular part defining the area of the second duct, and the area of the first duct is greater than the area of the second duct, and the second annular part is located between the first annular part and the impeller. 5. The mixer according to claim 4, characterized in that the second annular part is located around the circumference of at least part of the reflector and is aligned with it so as to receive fluid from it. 6. A mixer according to claim 4, characterized in that the second annular portion comprises a plurality of blades that are spaced apart from each other to form a plurality of ducts therebetween. 7. The mixer of claim 1, wherein the ratio of the cross-sectional area of the plurality of blades to the area of the second flow path is from about 1: 2 to about 4: 1. 8. The mixer according to claim 1, characterized in that the second annular part does not contain a band, as a result of which a plurality of ducts formed therein are open. 9. A mixer according to claim 4, wherein the first annular stator portion comprises a plurality of cross members connected to the housing. 10. A mixer according to claim 1, wherein the reflector comprises a plurality of reflector blades. 11. The mixer according to claim 1, wherein the reflector comprises a plurality of axially spaced discs. 12. The mixer according to claim 1, characterized in that the housing comprises an upper housing portion in which an inlet for additional components is at least partially formed, and a lower housing portion in which an inlet for additional components is at least partially formed. fluid, and the stator is at least one of: one piece with the lower part of the housing, the upper part of the housing, or both. 13. The mixer of claim 1, wherein the inlet for the additional component is adapted to receive the additional component by gravity. 14. The mixer of claim 1, wherein the housing, impeller, deflector and stator prevent air from the accessory inlet from being sucked into the fluid from the impeller by creating a vortex separation effect.