WO2019034939A1

WO2019034939A1 - High speed slurry pot testing apparatus

Info

Publication number: WO2019034939A1
Application number: PCT/IB2018/051688
Authority: WO
Inventors: Bhupendra Kumar Gandhi
Original assignee: Indian Institute Of Technology, Roorkee
Priority date: 2017-08-18
Filing date: 2018-03-14
Publication date: 2019-02-21

Abstract

The present disclosure relates to a slurry pot testing apparatus (200) for evaluating erosion behavior of one or more specimens (218), the apparatus (200) including a cylindrical pot (202) containing a solid-liquid mixture, a propeller (212) rotated by a first shaft (210), wherein the propeller (212) is installed at a specific height above bottom surface of the pot (202), and wherein rotation of the propeller (212) enables uniform distribution of solid particles in the solid-liquid mixture, and a plurality of baffles (204) provided at an inner surface of the pot (202), wherein the one or more specimens (218) are operatively coupled with a second shaft (216) by one or more fixing means (220), the second shaft (216) rotating in a direction opposite to rotation of the first shaft (210), and wherein the one or more fixing means (220) allow orientation of the one or more specimens (218) at different angles.

Description

HIGH SPEED SLURRY POT TESTING APPARATUS TECHNICAL FIELD

[0001] The present invention relates generally to erosion/wear testing devices, and more specifically, to a slurry pot testing apparatus that evaluates erosion behavior of different materials at high impact velocities and ensures uniform distribution of the solid particles in the testing apparatus.

BACKGROUND OF THE INVENTION

[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0003] Slurry erosion occurs in components handling a solid-liquid mixture. To estimate service life of these components, it is required to establish effect of various parameters and understand erosion mechanism. Generally, a pot tester is used to generate slurry erosion data at an accelerated rate under controlled environment. A pot tester is an abrasion/wear testing apparatus that evaluates erosion behaviour of different materials at moderate velocities. In a typical pot tester, one or more specimens are attached to a vertical rotating shaft in a pin mill configuration. However, the pin mill configuration of the pot tester restricts the evaluation of erosion behaviour of different materials at moderate velocities, and cannot withstand high impact velocities due to problems of turbulence and non-uniform distribution of solid particles associated at such high impact velocities.

[0004] In the past, many techniques have been implemented to evaluate erosion behaviour of different materials at higher impact velocities of solid particles suspended in solid-liquid mixture. One such technique employs a propeller attached at bottom of a vertical rotating shaft to lift a mixture of solid particles upwards to enable suspension of the solid particles in the liquid medium so as to form a solid-liquid mixture. However, random motion of solid particles inside the pot cannot be avoided due to turbulence produced in the pot. In addition, the solid particles have a certain velocity in the direction of rotation of the one or more specimens due to rotation of the propeller in the same direction, which results in a significant error in calculation of impact velocity. Moreover, a higher propeller speed develops excessive random motion inside the pot, and adds to attrition and rounding-off of the solid particles. Therefore in such techniques, evaluation of mass loss rate in a controlled manner is possible only at a low velocity range up to 9 m/s.

[0005] There is therefore a need in the art of pot tester apparatus that evaluates erosion behavior of different materials at high impact velocities of solid particles suspended in a solid-liquid mixture and ensures uniform distribution of the solid particles. Further, there exists a need to establish effect of various parameters and understand erosion mechanism of components handling solid-liquid mixture.

[0006] As used in the description herein and throughout the claims that follow, the meaning of "a," "an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.

[0007] In some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0008] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. "such as") provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0009] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

OBJECTS OF THE INVENTION

[0010] It is an object of the present disclosure to provide a slurry pot testing apparatus that evaluates erosion behavior of different materials handling a solid-liquid mixture.

[0011] It is another object of the present disclosure to provide a slurry pot testing apparatus that evaluates erosion behavior of different materials at high impact velocities.

[0012] It is yet another object of the present disclosure to provide a slurry pot testing apparatus that establishes effect of various parameters and provides understanding of erosion mechanism on different materials handling the solid-liquid mixture.

[0013] It is still another object of the present disclosure to provide a slurry pot testing apparatus that provides for uniform suspension of solid particles in the solid-liquid mixture.

SUMMARY

[0014] The present invention relates generally to erosion testing devices, and more specifically, to a slurry pot testing apparatus that evaluates erosion behavior of different materials at high impact velocities and ensures uniform distribution of the solid particles in the solid-liquid mixture.

[0015] Aspects of the present disclosure relate to an apparatus for evaluating erosion behavior of one or more specimens, the apparatus including a cylindrical pot containing a solid-liquid mixture, a propeller rotated by a first shaft, wherein the propeller is installed at a specific height above bottom surface of the pot, and wherein rotation of the propeller enables uniform distribution of solid particles in the solid-liquid mixture, and a plurality of baffles provided at an inner surface of the pot, wherein the one or more specimens are operatively coupled with a second shaft by one or more fixing means, the second shaft rotating in a direction opposite to rotation of the first shaft, and wherein the one or more fixing means allow orientation of the one or more specimens at different angles. In an aspect, the propeller is rotated in down-pumping mode.

[0016] In an aspect, the plurality of baffles are available at right angle to the bottom surface of the pot. [0017] In an aspect, the one or more fixing means comprises any or a combination of jigs and fixtures provided to operatively couple the one or more specimens with the second shaft. In an aspect, the one or more fixing means further comprise one or more slotted circular plates comprising a plurality of radial slots that allow orientation of the one or more specimens at different angles, wherein the one or more slotted circular plates enable orientation of any or a combination of jigs and fixtures of the one or more fixing means in different directions. In an aspect, the one or more fixing means are adapted to mount flat specimens. In an aspect, the one or more fixing means are orientated at different angles from 0° to 90° in steps of 15°.

[0018] In an aspect, the one or more specimens are rotated in a direction opposite to rotation of the propeller to achieve a proximal impact angle and a desired impact velocity of the solid particles.

[0019] In an aspect, the apparatus further includes a first motor with independent pulley drive for rotating the first shaft and a second motor with independent pulley drive for rotating the second shaft.

[0020] In an aspect, the apparatus further includes a first bearing housing to support the first shaft and a second bearing housing to support the second shaft, wherein the first bearing housing and the second bearing housing are operatively configured with any or a combination of oil seal and mechanical seal to prevent leakage of solid-liquid mixture.

[0021] In an aspect, the pot is covered at its top by a transparent acrylic plane sheet of a defined thickness.

[0022] In an aspect, shape and dimensions of the plurality of baffles are adapted to break vortex motion of the solid-liquid mixture being generated by the propeller.

[0023] It would be appreciated that although aspects of the present disclosure have been explained with respect to an apparatus for evaluating erosion behavior of different specimens/materials, the present disclosure is not limited to the same in any manner whatsoever and any other form of devices or apparatuses that handle a solid-liquid mixture is completely covered within the scope of the present disclosure.

[0024] Those skilled in the art will further appreciate the advantages and superior features of the disclosure together with other important aspects thereof on reading the detailed description that follows in conjunction with the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0026] In the figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label with a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

[0027] FIG. 1 illustrates an exemplary schematic representation of a conventional test rig for visualization of sand-water suspension in a transparent cylindrical tank in accordance with an embodiment of the present disclosure.

[0028] FIGs. 2A and 2B illustrate exemplary top view and side view of proposed slurry pot testing apparatus respectively in accordance with an embodiment of the present disclosure.

[0029] FIG 3 illustrates an exemplary representation of a slotted angular plate in accordance with an embodiment of the present disclosure.

[0030] FIG. 4 illustrates an exemplary representation of a test fixture in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

[0031] If the specification states a component or feature "may", "can", "could", or

"might" be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.

[0032] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This disclosure may however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those of ordinary skill in the art. Moreover, all statements herein reciting embodiments of the disclosure, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure).

[0033] Thus, for example, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and the like represent conceptual views or processes illustrating systems and methods embodying this disclosure. The functions of the various elements shown in the figures may be provided through the use of dedicated hardware as well as hardware capable of executing associated software. Similarly, any electronic code generator shown in the figures are conceptual only. Their function may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the entity implementing this disclosure. Those of ordinary skill in the art further understand that the exemplary hardware, software, processes, methods, and/or operating systems described herein are for illustrative purposes and, thus, are not intended to be limited to any particular named.

[0034] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.

[0035] Aspects of the present disclosure relate to an apparatus for evaluating erosion behavior of one or more specimens, the apparatus including a cylindrical pot containing a solid-liquid mixture, a propeller rotated by a first shaft, wherein the propeller is installed at a specific height above bottom surface of the pot, and wherein rotation of the propeller enables uniform distribution of solid particles in the solid-liquid mixture, and a plurality of baffles provided at an inner surface of the pot, wherein the one or more specimens are operatively coupled with a second shaft by one or more fixing means, the second shaft rotating in a direction opposite to rotation of the first shaft, and wherein the one or more fixing means allow orientation of the one or more specimens at different angles. In an aspect, the propeller is rotated in down-pumping mode.

[0036] FIG. 1 illustrates an exemplary schematic representation of a conventional test rig for visualization of sand-water suspension in a transparent cylindrical tank in accordance with an embodiment of the present disclosure. In an aspect, the tank 102 can include a plurality of baffles 104 that can act as a flow director and can break vortex motion of the solid-liquid mixture present in the tank 102. In an aspect, a propeller/stirrer 106 can be used to rotate in down-pumping mode to suspend solid-liquid mixture present in the tank 102. The propeller 106 can be connected to a shaft 108 such that a central axis of the shaft 108 coincides with rotating axis of the propeller 106. The shaft 108 can be inserted in the tank 102 from bottom side to fix the propeller 106 at a low off-bottom clearance distance, which can be rotated in down-pumping mode through the shaft 108 by a prime mover 110 such as, but not limited to, a direct current motor.

[0037] In an aspect, the prime mover 110 can impart rotary motion to the shaft 108 to effectuate rotation of the propeller 106. In an aspect, a bearing housing 112 can be operatively configured with the shaft 108 so as to support axial as well as radial loads of the shaft 108. It is to be appreciated that the bearing housing 112 can include any or a combination of radial bearing and thrust bearing.

[0038] FIGs. 2A and 2B illustrate exemplary top view and side view of proposed slurry pot testing apparatus respectively in accordance with an embodiment of the present disclosure. In an aspect, the slurry pot testing apparatus 200 can include a cylindrical stainless steel pot 202 operatively configured with four full length baffles 204 (as clearly shown in FIG. 2A) that are positioned equidistant from each other and are at right angle with bottom surface of the pot 202. In an aspect, the baffles 204 can act as flow director, and shape and dimensions of the baffles 204 are adapted to break vortex motion of the solid-liquid mixture being generated by the propeller 212, and thus prevents generation of whirlpool in the pot 202.

[0039] In an aspect, a first prime mover 206 can be operatively coupled with a first shaft 210 that is operatively coupled to a propeller/stirrer 212 installed at a specific height above the bottom surface of the pot 202. In an aspect, a second prime mover 214 can be operatively coupled with a second shaft 216 to rotate an arm 208 on which one or more specimens 218 (also referred to as test specimens or wear specimens hereinafter) are operatively coupled with the help of one or more suitable fixing means 220 such as any or a combination of jigs and fixtures (also referred to as test fixtures hereinafter).

[0040] In an aspect, the propeller 212 is rotated in down-pumping mode, wherein rotation of the propeller 212 in down-pumping mode generates a uniform pattern of flow, a single circulation loop of flow path is nearly radial outward and inward at bottom and top of the pot 202 respectively, while the flow is uniformly axial upward and downward near outer side and inner side of the pot 202 respectively. The baffles 204 are used to break the whirlpool and to direct the flow axially upward in the pot 202. By controlling the speed of the propeller 212, uniform distribution of solid particles in liquid medium is achieved for different particle sizes and concentrations with minimum turbulence. In an aspect, the propeller can include at least one 45° pitched turbine blade installed at low off-bottom clearance distance to develop uniform distribution of solid particles in liquid medium. In an aspect, there can be a plurality of the propeller of varied shapes and dimensions for suspending the solid-liquid mixture.

[0041] In an aspect, the one or more suitable fixing means 220 can further comprise one or more slotted circular plates 302 (as shown clearly in FIG. 3) comprising a plurality of radial slots that allow orientation of the one or more specimens 218 at desired angles, wherein the one or more slotted circular plates 302 enable orientation of any or a combination of jigs and fixtures of the one or more fixing means 220 in different directions. In an aspect, the one or more fixing means 220 are orientated at different angles from 0° to 90° in steps of 15°.

[0042] In an aspect, the one or more fixing means 220 are adapted to mount specimens having various shapes such as, but not limited to, flat, cylindrical, and spherical shapes. In an aspect, the one or more fixing means 220 can be hanged vertically downward or can be installed vertically upwards with the help of a horizontal arm 208.

[0043] In an aspect, the first prime mover 206 and second prime mover 214 can be operatively coupled with independent pulley drive mechanism to provide for transfer of rotary motion from the prime mover 206 and 214 to first shaft 210 and second shaft 216 respectively.

[0044] In an aspect, the first shaft 210 can be operatively coupled with a first bearing housing (not shown), and the second shaft 216 can be operatively coupled with a second bearing housing (not shown), wherein the first bearing housing and the second bearing housing are operatively configured with any or a combination of oil seal and mechanical seal to prevent leakage of solid-liquid mixture.

[0045] In an aspect, as illustrated in FIG. 2B, the one or more fixing means 220 can be operatively coupled with the second shaft 216. In an exemplary implementation, two test specimens 218 can be operatively coupled with the second shaft 216 with the help of fixture 220 coupled with horizontal arm 208 such that the test specimens can be provided in upward as well as downward direction.

[0046] In an aspect, the one or more fixing means 220 is placed in an area of minimum disturbances, which is downstream of the propeller 212. In this region, nearly uniform distribution of solid particles is observed. The one or more fixing means 220 can be rotated through second prime mover 214 at a test velocity in a direction opposite to rotation of the propeller 212 to achieve proximate impact angle and velocity effect to allow for efficient evaluation of erosion of the test specimens 218. [0047] In an aspect, an engagement and disengagement coupling 222 can be installed as a connection means between second prime mover 214 and second shaft 216. The engagement and disengagement coupling 222 can be used to fix and take out the test specimens 218 from the pot 202 by opening the transparent lid 224. A variable speed drive (not shown) can further be used to control rotation of the second shaft 216 by varying angular frequency of the second shaft 216 as per requirement.

[0048] In an aspect, pot 202 can be provided with a transparent lid 224, wherein the transparent lid (also referred to as top cover hereinafter) 224 can be made of an acrylic plane sheet of a defined thickness. In an aspect, the pot 200 can include a first hole (not shown) to fill solid particles and liquid medium and a second hole (not shown) to drain out slurry.

[0049] In an aspect, the apparatus 200 can withstand test velocity up to 32 m/s without suffering from non-uniform distribution of solid particles in the solid-liquid mixture present in the pot 202. In an aspect, erosion of the one or more specimens is evaluated based on measurement of mass loss rate to evaluate erosion of the one or more test specimens 218. It is to be appreciated that the proposed slurry pot testing apparatus 200 provides for evaluation and analysis of erosion of various materials to analyze various mechanical properties of such materials.

[0050] In an aspect, flow field inside the pot 202 containing the solid-liquid mixture is very complex due to rotation of the propeller 212 and the test specimens 218. If the propeller 212 and test specimens 218 are to be rotated by a single prime mover through a common shaft, the vortex generated by the propeller 212 increases with increase in test velocity and at the same time shedding of vortices from rotating test fixtures 220 interferes with the specimens 218. This phenomenon may develop large errors in evaluating erosion. In the present invention, the propeller 212 and wear specimens 218 are rotated by different prime movers 206 and 214 through separate shafts (first shaft and second shaft) and the speed of the former is kept constant to achieve nearly uniform distribution of solid particles. In this implementation, the test speed is increased by increasing rotational speed of test fixtures 220 only and uniform turbulence level can be maintained by keeping the rotational velocity of propeller 212 constant. However, due to vortex shedding by the rotating test fixtures 220, the test velocity can be limited to a maximum velocity of 32 m/s.

[0051] FIG 3 illustrates an exemplary representation of slotted angular plate in accordance with an embodiment of the present disclosure. In an aspect, the slotted angular plate 302 includes a number of radial slots/divisions 304. Shape and dimensions of the plate 302 is adapted to orient the test specimens 218 in a desired impact angle range. The slotted angular plate 302 is brazed to fixture 220, as shown in FIG. 2, to orient the fixture 220 and the test specimens 218 at different angles in a desired range.

[0052] FIG. 4 illustrates an exemplary representation of a test fixture in accordance with an embodiment of the present disclosure. In an aspect, shape and dimensions of the test fixture 220 is adapted to mount test specimens 218. The test fixture 220 can include a groove 402 to fix a test specimen 218 with plane surface flushing to upper face 404 of the fixture 220. The fixture 220 can be oriented at different angles with respect to its rotational direction with the help of slotted angular plate 302 and the fixture 220 can be coupled with the plate 302 by using a screw. The fixture 220 can be hanged vertically downward or can be installed vertically upwards through horizontal arm 208, as shown in FIG. 2, and center of the fixture 220 can be kept at an equal distance from top cover 224 and center of propeller 212.

[0053] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ....and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.

[0054] While embodiments of the present disclosure have been illustrated and described, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

ADVANTAGES OF THE INVENTION

[0055] The present disclosure provides a slurry pot testing apparatus that evaluates erosion behavior of different materials handling a solid-liquid mixture.

[0056] The present disclosure provides a slurry pot testing apparatus that evaluates erosion behavior of different materials at high impact velocities.

[0057] The present disclosure provides a slurry pot testing apparatus that establishes effect of various parameters and provides understanding of erosion mechanism on different materials handling the solid-liquid mixture.

[0058] The present disclosure provides a slurry pot testing apparatus that provides for uniform suspension of solid particles in the solid-liquid mixture.

Claims

We Claim:

1. An apparatus for evaluating erosion behavior of one or more specimens, the apparatus comprising: a cylindrical pot containing a solid-liquid mixture; a propeller rotated by a first shaft, wherein the propeller is installed at a specific height above bottom surface of the pot, and wherein rotation of the propeller enables uniform distribution of solid particles in the solid-liquid mixture; and a plurality of baffles provided at an inner surface of the pot; wherein the one or more specimens are operatively coupled with a second shaft by one or more fixing means, the second shaft rotating in a direction opposite to rotation of the first shaft, and wherein the one or more fixing means allow orientation of the one or more specimens at different angles.

2. The apparatus of claim 1, wherein the propeller is rotated in down-pumping mode.

3. The apparatus of claim 1, wherein the plurality of baffles are available at right angle to the bottom surface of the pot.

4. The apparatus of claim 1, wherein the one or more fixing means comprises any or a combination of jigs and fixtures provided to operatively couple the one or more specimens with the second shaft.

5. The apparatus of claim 1, wherein the one or more fixing means further comprise one or more slotted circular plates comprising a plurality of radial slots that allow orientation of the one or more specimens at different angles.

6. The apparatus of claim 5, wherein the one or more slotted circular plates enable orientation of any or a combination of jigs and fixtures of the one or more fixing means in different directions.

7. The apparatus of claim 1, wherein the one or more fixing means are adapted to mount flat specimens.

8. The apparatus of claim 1, wherein the one or more fixing means are orientated at different angles from 0° to 90° in steps of 15°.

9. The apparatus of claim 1, wherein the one or more specimens are rotated in a direction opposite to rotation of the propeller to achieve a proximal impact angle and a desired impact velocity of the solid particles.

10. The apparatus of claim 1, comprising a first motor with independent pulley drive for rotating the first shaft and a second motor with independent pulley drive for rotating the second shaft.

11. The apparatus of claim 1, comprising a first bearing housing to support the first shaft and a second bearing housing to support the second shaft.

12. The apparatus of claim 11, wherein the first bearing housing and the second bearing housing are operatively configured with any or a combination of oil seal and mechanical seal to prevent leakage of solid-liquid mixture.

13. The apparatus of claim 1, wherein the pot is covered at its top by a transparent acrylic plane sheet of a defined thickness.

14. The apparatus of claim 1, wherein shape and dimensions of the plurality of baffles are adapted to break vortex motion of the solid-liquid mixture being generated by the propeller.