DESC:FIELD
The present disclosure relates to the field of mechanical and process engineering. In particular, the present disclosure relates to the field of dispersion equipments.
BACKGROUND
Dispersion is a process of dispersing solid particles in a liquid. Homogeneous dispersion of solid particles in a liquid is typically required for various applications in process industry. For example, in paint industry, various colour pigments are added in liquid solvent in order to achieve homogenous solution in form of paint as final product. Such pigments, which are solid particles, are not easily soluble in the liquid solvent, and therefore, require to be homogeneously dispersed in the liquid solvent. Further, such pigments or solid particles are required to be broken down into smaller pieces to achieve homogeneous dispersion. Typically, such dispersion is achieved by exerting a shearing force onto the solid particles present in the liquid. However, conventional equipments used for dispersing solid particles in the liquid do not produce a homogeneous mixture of the dispersed solid particles in liquid. The presence of undispersed solid particles, like pigments, in the liquid causes nonhomogeneous mixing, thereby affecting the very cause for which the mixture is to be used. Furthermore, if the mixing components are viscous, they have a tendency to stick to walls of a vessel in which they are mixed. Such fluid adhered to the walls require to be dislodged from the walls by scraping action, and pushed towards the center of the vessel. The conventional equipments are unable to perform such action. Further, the conventional equipments consumes a lot of time to accomplish the dispersion process.
Therefore, there is felt a need for an equipment which can accomplish homogeneous dispersion of solid particles in a liquid, and is also time effective.

OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
An object of the present disclosure is to provide an equipment for making a homogenous dispersion that produces homogeneous mixture of dispersed solid particles in a liquid.
Another object of the present disclosure is to provide an equipment that imparts high shear and cutting force onto the solid particles in a liquid to achieve effective dispersion.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a twin shaft disperser equipment for making a homogenous dispersion. The equipment comprises a vessel, a first shaft, a first impeller, and a first motor. The first shaft is disposed within the vessel and extends therefrom. The first impeller is disposed within the vessel, and is attached to the first shaft. The first motor is coupled with the first shaft, and is configured to rotate the first shaft. The equipment further comprises a second shaft, a second impeller, and a second motor. The second shaft is disposed within the vessel and extends therefrom. The second shaft is configured to circumscribe the first shaft therewithin. The second impeller is disposed within the vessel, and is attached to the second shaft. The second motor is coupled with the second shaft, and is configured to rotate the second shaft.
In an embodiment, the first impeller has a plurality of teeth configured at periphery of the first impeller. Each tooth of the plurality of teeth is configured perpendicular to the surface of the first impeller, and extends in opposite direction with respect to adjacent tooth. In an exemplary embodiment, number of the plurality of teeth ranges from 18 to 32.
In another embodiment, second impeller comprises two anchors extending from said second shaft.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A twin shaft disperser equipment for making a homogeneous dispersion will now be described with the help of the accompanying drawing in which:
Figure 1 illustrates a cross-sectional front view of the equipment for making homogeneous dispersion, in accordance with an embodiment of the present disclosure;
Figure 2 illustrates an isometric view of the equipment of figure 1; and
Fig. 3 illustrates an isometric view of a first impeller of the equipment of figure 1.
DETAILED DESCRIPTION
The present disclosure envisages a twin shaft disperser equipment for making a homogeneous dispersion that produces homogeneous mixture of the dispersed solid particles in a liquid.
The equipment, of the present disclosure, is now described with reference to figure 1 through figure 3.
Figure 1 illustrates a cross-sectional front cut away view of a twin shaft disperser equipment for making a homogeneous dispersion (herein after referred to as equipment 100), in accordance with an embodiment of the present disclosure. Figure 2 illustrates an isometric view of the equipment 100 of figure 1. Figure 3 illustrates an isometric view of a first impeller 140 of the equipment 100 of figure 1.
The equipment 100 comprises a vessel 102, a first shaft 104, a first impeller 140, and a first motor 126. The first shaft 104 is disposed within the vessel 102 and further extends from an operative upper end of the vessel 102. The first shaft 104 is defined by an operative upper end 104A and an operative bottom end 104B. The first motor 126 is coupled to the first shaft 104. The first motor 126 is configured to rotate the first shaft 104.
In an embodiment, the first motor 126 is coupled with the first shaft 104 via a first belt drive 128. The belt drive includes a V-belt (not exclusively labeled in figures). A first pulley 130 is mounted on the operative upper end 104A of the first shaft 104. A second pulley 132 is mounted on the output shaft (not exclusively labeled in figures) of the first motor 126. The V-belt is used to couple the first pulley 130 with the second pulley 132. A support structure 134 is provided to support the first motor 126 and the first shaft 104.
In a preferred embodiment, the first motor 126 is configured to rotate the first shaft 104 at the rotational speed ranging from 200 revolutions/minute to 3000 revolutions/minute. In an embodiment, the rotational speed is controlled by using a variable frequency drive (not shown in figures).
In a preferred embodiment, the first shaft 104 is a solid shaft.
The first impeller 140 is disposed within the vessel 102, and is attached to the first shaft 104. In an embodiment, the first impeller 140 is attached at the operative lower end 104B of the first shaft 104. The first impeller 140 is a saw tooth impeller having a plurality of teeth 142. The first impeller 140 is defined by a body 141 having circular configuration. The plurality of teeth 142 is configured at the periphery of the body 141 of the first impeller 140. In an embodiment, each of the plurality of teeth 142 has a trapezoidal shape. Furthermore, each of the plurality of teeth 142 is configured perpendicular to the operative upper surface of the body 141 of the first impeller 140. More specifically, each of the plurality of teeth 142 is cut and bent in such a way that if one tooth is bent in an operative upward direction with respect to the operative upper surface of the body 141 of the first impeller 140 then the consecutive tooth is bent in an operative downward direction with respect to the operative upper surface of the body 141 of the first impeller 140. In a preferred embodiment, all the teeth 142 are bent at right angles with respect to the operative upper surface of the body 141 of the first impeller 140.
In an embodiment, the total number of the plurality of teeth 142 of the first impeller 140 ranges from 18 to 32. In another embodiment, the thickness of the first impeller 140 ranges from 6 mm to 16 mm.
The first impeller 140 is provided to separate solid particles or pigment agglomerates from each other in viscous liquid by the transmission of shear forces. The shear forces generated by flow are enhanced by supplementary rotation of the solid particles by centrifugal forces. With the increase in tip speed of the first impeller 140, shear force exerted by the first impeller 140 also increases.
In an embodiment, the first impeller 140 has a diameter having value 25% to 30% to that of inner diameter of the vessel 102. The first impeller 140 is disposed within the vessel 102 at a height of half the diameter of the first impeller 140 from the base of the vessel 102.
In another embodiment, the tip speed of the first impeller 140 is in the range of 12 m/s to 30 m/s in order to achieve homogeneous dispersion.
The equipment 100 further comprises a second shaft 106, a second impeller 108, and a second motor 112. The second shaft 106 is disposed within the vessel 102 and extends from the operative upper end of the vessel 102. The second shaft 106 is defined by an operative upper end 106A and an operative bottom end 106B. Further, the second shaft 106 is configured to circumscribe the first shaft 104 therewithin. More specifically, the second shaft 106 has hollow configuration and the first shaft 104 is inserted through the second shaft 106. The second shaft 106 receives the first shaft 104 coaxially. Enough clearance is provided between the first shaft 104 and the second shaft 106 in order to facilitate easy rotation of the first shaft 104 within the second shaft 106. In an embodiment, the length of the first shaft 104 is smaller than that of the second shaft 106.
The second motor 112 is coupled with the second shaft 106 and is configured to rotate the second shaft 106. In an embodiment, the second motor 112 is coupled with the second shaft 106 via a second belt drive 114. In an embodiment, a gearbox 120 is disposed between the second motor 112 and the second shaft 106. The output shaft of the second motor 112 is coupled with the input shaft of the gearbox 120, and the output shaft of the gearbox 120 is coupled with the operative upper end 106A of the first shaft 104 via the second belt drive. The gearbox 120 is configured to vary the rotational speed of the second shaft 106. A housing 118 is provided to cover the second belt drive 114 and to support the second motor 112 and the gearbox 120.
The second shaft 106 is configured to generate radial flow within the vessel 102, and dislodge any solid particles adhered to the walls of the vessel 102. The radial flow is required to ensure that the flow is directed on the first impeller 140 to achieve homogeneous dispersion.
The second belt drive 114 includes a V-belt (not exclusively labeled in figures), a third pulley 116, and a fourth pulley (not shown in figures). The third pulley 116 is mounted on the operative upper end 106A of the second shaft 106. The fourth pulley is mounted on the output shaft of the gearbox 120.
In a preferred embodiment, the second motor 112 is configured to rotate the second shaft 106 at the rotational speed ranging from 15 revolutions/minute to 60 revolutions/minute.
The second impeller 108 is disposed within the vessel 102. The second impeller 108 is attached to the second shaft 106. In an embodiment, the second impeller 108 is attached at the operative bottom end 106B of the second shaft 106.
The second impeller 108 includes at least one anchor 109. In an embodiment, the second impeller 108 includes two anchors 109. The two anchors 109 extend outwardly from the second shaft 106. The anchors 109 are configured such that there is very small clearance between the inner walls of the vessel 102 and the anchors 109.
The equipment 100 further comprises a support frame 150. The support frame is configured to support the first shaft 104, the second shaft 106, the first motor 126, and housing 118. The support frame includes a base plate 152, a guide bar 154, and a pneumatic cylinder 156. The base plate 152 is attached to the operative upper surface of the vessel 102. The guide bar 154 and the pneumatic cylinder 156 are mounted on the base plate 152. A support bar 158 is attached to the guide bar 154 and the pneumatic cylinder 156. The support bar 158 is configured to slide over the guide bar 154. The support bar 158 is configured to support the first motor 126 and the first shaft 104. The pneumatic cylinder 156 is configured to alter the height of the support bar 158 with respect to the vessel 102. This configuration facilitates alteration in the height of the first motor 126 with respect to the vessel 102 in order to accommodate varying length of the first shaft 104 and to ease the coupling between the first motor 126 and the first shaft 104. Further, the height of first shaft 104 can also be altered using the pneumatic cylinder 156 in order to achieve better mixing. The support frame 150 has a better stability and lesser vibration generation.
In an embodiment, a hydraulic cylinder is used to alter the height of the support bar 158 instead of the pneumatic cylinder 156.
The operational configuration of the equipment 100 is now described in subsequent sections.
A liquid and solid particles to be dispersed in the liquid, are introduced to the vessel 102 through an opening provided at the operative upper end of the vessel 102. The two motors viz. the first motor 126 and the second motor 112, are then started to operate the first belt drive 128 and the second belt drive 114 respectively. The first belt drive 128 drives the first shaft 104 while the second belt drive 114 drives the second shaft 106. The belt drives 114 and 128 are configured in such a way that the rotational speed of the first shaft 104 is greater than the second shaft 106. Therefore, the anchors 109 rotate at lower speed than the first shaft 104. The first shaft 104 typically operates at the rotational speed which ranges from 200 revolutions/minute to 3000 revolutions/minute. The second shaft 106 typically operates at the rotational speed which ranges from 15 revolutions/minute to 60 revolutions/minute. The high speed of the first shaft 104 creates a vortex in the vessel 102. Due to the vortex formation, the solid particles moves from top of the vessel 102 to bottom of the vessel 102 along the longitudinal axis of the first shaft 104. Because of the first impeller 140, which is connected to the operative bottom end 104B of the first shaft 104, the solid particles get cut by the sharp edges of the plurality of teeth 142 and size of the solid particles gets reduced. The anchors 109 of the second impeller 108 dislodge the solid particles which may adhere to the inner surface of the vessel 102. The operation of the first impeller 140 and the second impeller 108 is continued until a desired size of the solid particles is achieved, so that they can be homogeneously dispersed in the liquid contained within the vessel 102.
The equipment envisaged in the present disclosure imparts high shear and cutting force onto the solid particles in a liquid by virtue of sharp teeth of the first impeller, thereby achieving effective dispersion.
The equipment 100 generates high shearing stress to disperse the solid particles. Further, the equipment 100 is a self-cleaning equipment.
As compared to conventional equipment used for dispersion, the equipment 100 performs more than one operation simultaneously. The operations performed by the equipment 100 include shearing of solid particles, dislodging of solid particles, and heat transfer between mixing components. The equipment 100 consumes lesser time to achieve homogeneous dispersion. It is observed that, the equipment 100 requires 15% to 35% lesser time as compared to conventional equipment. Further, the equipment has a lifting arrangement for the first impeller. Such arrangement is absent in the conventional equipment. Due to use of two impellers 140, 108, the equipment 100 facilitates production of better homogeneous mixtures. The equipment requires lesser space and has better mechanical reliability as compared to the conventional equipment. Furthermore, the equipment 100 requires lesser initial investment as all the operations are performed in a single vessel.
The equipment 100 is particularly useful in paint manufacturing processes, wherein pigments are needed to be homogeneously dispersed in a base solvent. The equipment 100 can be used in any other similar applications where solid particles are required to be dispersed in a liquid. Some of the examples of such applications are chocolate manufacturing industry, cosmetics industry, food product industry, preparation of adhesives etc.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including but not limited to an equipment that:
• produces homogeneous mixture of the dispersed solid particles in a liquid;
• imparts high shear and cutting force onto the solid particles in a liquid to achieve effective dispersion;
• has a robust configuration; and
• has impellers which are easily removable from the shafts.
The disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully revealed 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 embodiments as described herein.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

,CLAIMS:1. A twin shaft disperser equipment (100) for making a homogenous dispersion, said equipment comprising:
a vessel (102);
a first shaft (104) disposed within said vessel (102) and extending therefrom;
a first impeller (140) disposed within said vessel (102) and attached to said first shaft (104); and
a first motor (126) coupled with said first shaft (104), and configured to rotate said first shaft (104).
2. The equipment (100) as claimed in claim 1, which further comprises:
a second shaft (106) disposed within said vessel (102) and extending therefrom, said second shaft (106) configured to circumscribe said first shaft (104) therewithin;
a second impeller (108) disposed within said vessel (102) and attached to said second shaft (106); and
a second motor (112) coupled with said second shaft (106), and configured to rotate said second shaft (106).
3. The equipment (100) as claimed in claim 2, wherein said second impeller (108) comprises two anchors (109) extending from said second shaft (106).
4. The equipment (100) as claimed in claim 1, wherein said first impeller (140) has a plurality of teeth (142) configured at periphery of said first impeller (140).
5. The equipment (100) as claimed in claim 4, wherein each tooth of said plurality of teeth (142) is configured perpendicular to the surface of said first impeller (140), and extends in opposite direction with respect to adjacent tooth.
6. The equipment (100) as claimed in claim 4, wherein number of said plurality of teeth (142) ranges from 18 to 32.
7. The equipment (100) as claimed in claim 2, wherein:
said first motor (126) is coupled to said first shaft (104) via a first belt drive (128); and
said second motor (112) is coupled to said second shaft (106) via a second belt drive (114).
8. The equipment (100) as claimed in claim 2, wherein the rotational speed of said first shaft (104) ranges from 200 revolutions/minute to 3000 revolutions/minute, and the rotational speed of said second shaft (106) ranges from 15 revolutions/minute to 60 revolutions/minute.
9. The equipment (100) as claimed in claim 2, which includes a gearbox (120) coupled with said second shaft (106) and said second motor (112), and configured to vary the rotational speed of said second shaft (106).
10. The equipment (100) as claimed in claim 2, which further comprises a support frame (150) configured to support said first shaft (104), said second shaft (106), said first motor (126), and said second motor (112).