A mixing device for preparing urea for vehicles

Abstract

The application relates to the technical field of chemical mixing devices, and particularly discloses a mixing device for preparing vehicle urea, which comprises a supporting seat and a mixing tank, the mixing tank is vertically fixed in a mounting groove of the supporting seat, an annular cavity is arranged in the supporting seat and is in close contact with the lower end of the mixing tank, a plug column is rotationally connected to the center of the upper end of the mixing tank, a driving assembly for realizing the rotation of the plug column is arranged on the mixing tank, a serpentine heat exchange pipe is arranged in the mixing tank, both ends of the serpentine heat exchange pipe pass through the plug column, a cylindrical body is fixedly arranged above the plug column, and a circular plate is rotationally connected to the lower end opening of the cylindrical body; the mixing device has good stirring function and better heating effect, the mixing efficiency of the vehicle urea is effectively improved, the temperature of the mixed liquid with different liquid depths is kept the same, and the product quality of the obtained vehicle urea is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of chemical mixing equipment technology, and specifically discloses a mixing device for preparing automotive urea. Background Technology

[0002] Automotive urea is a type of exhaust gas treatment fluid used in oilfield rigs and is an essential consumable in SCR (Selective Catalytic Reduction) technology. During SCR system operation, when nitrogen oxides are detected in the exhaust pipe, the urea tank automatically dispenses automotive urea. The automotive urea and nitrogen oxides then undergo a redox reaction in the SCR catalytic converter, producing harmless nitrogen gas and water vapor, which are then discharged. The production process of automotive urea involves mixing high-purity urea and pure water in a specific ratio to dissolve them. However, since the dissolution of urea in water is an endothermic process, the liquid temperature drops during mixing. This temperature drop reduces the solubility of urea. Therefore, a heating jacket is installed outside the mixing tank during the automotive urea mixing process, using a high-temperature medium inside the jacket to heat the mixture.

[0003] For example, utility model patent application number 201920169486X discloses a urea solution preparation tank, which includes a tank body and a tank cover. A protective shell is fitted around the outside of the tank body. A support platform is provided at the bottom of the protective shell. A water inlet is provided at the left end of the protective shell, and a water outlet is provided at the right end of the protective shell. A geared motor is mounted on the upper end of the tank cover via a mounting base. A rotating rod is connected to the bottom end of the geared motor via a coupling. A stirring rod is mounted on the rotating rod through the tank cover and via a bushing. A stirring blade is embedded at the end of the stirring rod. The urea solution preparation tank disclosed in this patent heats the solution through a high-temperature heat exchange medium inside the casing and steam coil during the preparation of automotive urea, while stirring is achieved through a geared motor, rotating rod, and stirring blades. This allows for effective mixing and preparation of automotive urea to a certain extent. However, the casing and steam coil can only heat the solution from the outside in, leading to a decrease in the urea dissolution rate. Furthermore, the temperature difference at different liquid levels within the tank results in variations in urea solubility in the mixture, failing to effectively guarantee the quality of the finished automotive urea. Based on these shortcomings of existing urea solution preparation tanks, this application proposes a novel structural design for a mixing device in the preparation of automotive urea to address these deficiencies. Summary of the Invention

[0004] The present invention aims to provide a mixing device for preparing automotive urea, so as to solve the problems of slow solution heating rate and temperature difference between different liquid levels in existing urea solution preparation tanks, which lead to poor quality of finished automotive urea products.

[0005] This invention is achieved through the following technical solution:

[0006] A mixing device for preparing automotive urea includes a support base and a mixing tank. The mixing tank is vertically fixed in the mounting groove of the support base. The support base has an annular cavity that fits against the lower end of the mixing tank. A heater and a temperature sensor for processing and detecting the heat exchange medium are installed in the annular cavity.

[0007] A stopper is rotatably connected to the upper center of the mixing tank. A drive assembly for rotating the stopper is provided on the mixing tank. A serpentine heat exchange tube is provided in the mixing tank, with both ends of the serpentine heat exchange tube passing through the stopper. A cylindrical body is fixedly provided directly above the stopper. A circular plate is rotatably connected to the lower opening of the cylindrical body. A pipe port connecting sleeve is provided at the inner center of the cylindrical body. One end of the serpentine heat exchange tube passes through the circular plate and is rotatably connected to the pipe port connecting sleeve, while the other end passes through the circular plate and communicates with the inside of the cylindrical body. A first infusion tube communicating with an annular cavity is connected to the pipe port connecting sleeve, and a circulation pump is provided on the first infusion tube. A second infusion tube communicating with the annular cavity is connected to the cylindrical body.

[0008] As a further provision of the above scheme, each bend of the serpentine heat exchange tube is connected to a mixing liquid agitation assembly. The mixing liquid agitation assembly includes a connecting pipe body connected to the serpentine heat exchange tube. A rotating shaft extending from both sides of the connecting pipe body is rotatably connected in the connecting pipe body. An impeller is provided on the rotating shaft located inside the connecting pipe body, and agitation blades are connected on the rotating shaft located outside the connecting pipe body.

[0009] As a specific arrangement of the above scheme, multiple mixing liquid agitation components are staggered vertically on each bend of the serpentine heat exchange tube.

[0010] As a further provision of the above scheme, a first measuring cylinder and a second measuring cylinder are respectively provided on both sides of the mixing tank. The lower ends of the first measuring cylinder and the second measuring cylinder are connected to a discharge pipe that communicates with the mixing tank. The lower end of the mixing tank is connected to a discharge pipe. Valves are provided on both the discharge pipe and the discharge pipe.

[0011] As a specific feature of the above scheme, a sealed bearing is provided at the center of the upper end of the mixing tank, and the plunger is inserted into the sealed bearing.

[0012] As a specific configuration of the above scheme, the drive assembly includes a first gear connected to the upper end of the plunger and a mixing motor fixed on the mixing tank, and a second gear meshing with the first gear is connected to the output shaft of the mixing motor.

[0013] As a specific configuration of the above scheme, the support includes a base and several legs, the legs being connected to the lower surface of the base, and the annular cavity being formed in the base.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The mixing device for preparing automotive urea disclosed in this invention can heat the bottom of the mixing tank through a high-temperature heat exchange medium in an annular cavity during the initial mixing stage. Then, the heat exchange medium is transported along a serpentine heat exchange tube by a circulating pump. During the transport of the heat exchange medium, the serpentine heat exchange tube rotates continuously inside the mixing tank. This not only fully stirs the mixture, but also heats the mixture synchronously from all directions without dead angles during the stirring process. As a result, the mixture inside the tank can be rapidly heated to the required temperature. The entire mixing device has both good stirring function and better heating effect, effectively improving the mixing efficiency of automotive urea.

[0016] The mixing device for preparing automotive urea disclosed in this invention is further designed by setting a mixing liquid agitation component on a serpentine heat exchange tube. The flow of the heat exchange medium during the heat exchange tube transportation process causes the rotating shaft to rotate. Under the action of the rotating shaft, the agitation blades outside the heat exchange tube rotate continuously. Then, under the action of the agitation blades, the mixing liquid can move up and down continuously inside the mixing tank. This not only enables the mixing liquid inside the tank to be quickly and evenly mixed, but also enables the mixing liquid at different liquid levels to be continuously agitated, so that the temperature of the mixing liquid at all different liquid levels is kept the same, thereby ensuring the quality of the final automotive urea product. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention from a first angle;

[0019] Figure 2 This is a schematic diagram of the second-angle three-dimensional structure of the present invention;

[0020] Figure 3 This is a schematic diagram of the internal planar structure of the present invention from the front view.

[0021] Figure 4 For the present invention Figure 3 Enlarged structural diagram at point A in the middle;

[0022] Figure 5 This is a schematic diagram of the three-dimensional structure of the cylindrical body, sealing circular plate, plug, and hybrid motor in this invention;

[0023] Figure 6 This is a three-dimensional structural diagram of the plug, heat exchange tube, and mixing liquid agitation assembly in this invention;

[0024] Figure 7 This is a three-dimensional structural diagram of the mixing liquid agitation component in this invention. Implementation

[0025] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The following will refer to the appendix... Figures 1-7 This application will be described in detail with reference to the embodiments. Example

[0027] Example 1 discloses a mixing apparatus for the preparation of automotive urea, see attached figure. Figure 1 and attached Figure 2 The mixing device includes a support base 1 and a mixing tank 2. Specifically, the support base 1 includes a base body 101 and several support legs 102. The support legs 102 are evenly connected to the lower surface of the base body 101, and a mounting groove for mounting the mixing tank 2 is formed at the center of the base body 101, thus allowing the mixing tank 2 to be vertically fixed on the base body 101. An annular cavity 103 is formed inside the support base 1 outside the mounting groove, and this annular cavity 103 is in contact with the lower outer wall of the mixing tank 2. A heater 104 and a temperature sensor 105 are disposed inside the annular cavity 103. The annular cavity 103 is also filled with a heat exchange medium, typically water or thermal oil. The heater 104 heats the heat exchange medium to a set temperature range.

[0028] Reference Appendix Figure 3A first measuring cylinder 3 and a second measuring cylinder 4 are fixedly installed on the left and right sides of the mixing tank 2 located above the support base 1, respectively. Both the first measuring cylinder 3 and the second measuring cylinder 4 are vertically fixed to the outer side of the mixing tank 2 or to the upper end of the support base 1. The lower ends of both the first measuring cylinder 3 and the second measuring cylinder 4 are connected to a discharge pipe 301 extending into the mixing tank 2, and each discharge pipe 301 is equipped with a control valve 302. In addition, to facilitate real-time reading of the raw material dosage, both the first measuring cylinder 3 and the second measuring cylinder 4 are equipped with measuring scales 303. Finally, a discharge pipe 201 extending from the lower end of the support base 1 is connected to the lower end of the mixing tank 2, and the discharge pipe 201 is equipped with a corresponding discharge valve. In the process of preparing automotive urea, the first measuring cylinder 3 is filled with pure water and the second measuring cylinder 4 is filled with high-purity urea solution. Then, the control valves 302 on the corresponding feed pipes 301 are opened in sequence so that the raw materials can be quantitatively added to the mixing tank 2 for subsequent mixing. After the mixing is completed, the discharge valve is opened to discharge the material from the discharge pipe 201.

[0029] Reference Appendix Figure 4 and attached Figure 5 A sealed bearing 5 is provided at the center of the upper surface of the mixing tank 2. A plug 6, which rotates with the sealed bearing 5, is provided in the inner ring of the sealed bearing 5. A first gear 7 is connected to the upper end of the plug 6 that extends out of the sealed bearing 5. A heat exchange tube 8 is provided inside the mixing tank 2. In this figure, the heat exchange tube 8 is in a serpentine shape with multiple bends, and both ends of the heat exchange tube 8 extend out of the mixing tank 2 through the plug 6 and the first gear 7.

[0030] A cylindrical body 9 is fixedly installed on the upper surface of the mixing tank 2 directly above the first gear 7. The upper end of the cylindrical body 9 is sealed, and the lower end is open. A sealing disc 10 is rotatably connected to the lower end opening of the cylindrical body 9. Specifically, the sealing disc 10 matches the annular groove at the lower end of the inner wall of the cylindrical body 9, and a corresponding sealing rubber strip is provided at the rotatable connection between the two to prevent liquid leakage. A circulation pump 11 is fixedly installed on the base 101. The inlet end of the circulation pump 11 is connected to the annular cavity 103, and a first delivery pipe 12 is connected to the outlet end of the circulation pump 11. The end of the first delivery pipe 12 extends into the interior of the cylindrical body 9. A pipe port connecting sleeve 13 is connected to the end of the first conveying pipe 12 located inside the cylindrical body 9, and the pipe port connecting sleeve 13 and the sealing bearing 5 are arranged along the same central axis. Then, one end of the heat exchange tube 8 is sealed through the sealing circular plate 10 and is rotatably connected to the pipe port connecting sleeve 13, and the other end of the heat exchange tube 8 is sealed through the sealing circular plate 10 and extends into the interior of the cylindrical body 9.

[0031] Finally, a second conveying pipe 14 is connected to the cylindrical body 9, and the end of the second conveying pipe 14 is connected to the seat body 101 so that it is connected to the annular cavity 103. Then, a mixing motor 15 is provided at the upper end of the mixing tank 2, and a second gear 16 is provided on the motor shaft of the mixing motor 15, and the second gear 16 is meshed with the first gear 7.

[0032] When the mixing device disclosed in this embodiment 1 is used for mixing automotive urea, high-purity urea solution and pure water are first added to the inside of the mixing tank 2 in proportion through the first measuring cylinder 3 and the second measuring cylinder 4. At the same time, the heater 104 inside the annular cavity 103 is activated to heat the heat exchange medium. After the heat exchange medium inside the annular cavity 103 is heated, the bottom of the mixing tank 2 can be heated.

[0033] Next, the circulating pump 11 is started to deliver the heated heat exchange medium to the inside of the heat exchange tube 8. The heat exchange tube 8 contacts the raw material inside, allowing it to quickly exchange heat and heat up. At the same time, the mixing motor 15 can be started to rotate the plunger 6 around the sealed bearing 5 through the meshing transmission between gears. At this time, the heat exchange tube 8 inside the mixing tank 2 will also rotate to stir the raw material inside, thereby effectively accelerating the heating speed of the raw material inside, making the temperature of the raw material in each area almost the same and the temperature difference of the raw material inside the tank small. Example

[0034] Example 2 discloses a mixing device for preparing automotive urea that is an improvement on Example 1. The main purpose is to improve the rapid mixing of raw materials at different liquid levels inside the mixing tank 2, so that the mixing temperature of raw materials at each liquid level can always be kept the same during the mixing of automotive urea, and there is no temperature difference.

[0035] The similarities between Example 1 and Example 2 will not be repeated here; the differences are detailed in the appendix. Figure 3 Appendix Figure 6 and attached Figure 7 In this embodiment 2, a mixture agitation assembly 17 is connected to each bend of the heat exchange tube 8, and the mixture agitation assemblies 17 are staggered in the vertical direction. Specifically, each mixture agitation assembly 17 includes a connecting pipe body 171 sealed to the heat exchange tube 8, and a rotating shaft 172 rotatably connected within the connecting pipe body 171, extending transversely through the entire connecting pipe body 171. An impeller (not shown in the figure) is provided on the rotating shaft 172 located inside the connecting pipe body 171. This impeller causes the rotating shaft 172 to rotate in a specific direction under the flow of the heat exchange medium. Finally, agitation blades 173 are connected to both ends of the rotating shaft 172 outside the connecting pipe body 171.

[0036] In this embodiment 2, during the flow of the heat exchange medium inside the heat exchange tube 8, the rotating shaft 172 rotates due to the interaction between the heat exchange medium and the impeller. Then, during the rotation of the rotating shaft 172, the mixing liquid inside the mixing tank 2 is turned up and down by the flipping blades 173, so that the mixing liquids at different liquid levels can be quickly and evenly mixed, eliminating the temperature difference between the mixing liquids at different liquid levels inside the mixing tank 2.

[0037] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A mixing device for preparing automotive urea, comprising a support base and a mixing tank, wherein the mixing tank is vertically fixed in a mounting groove of the support base, characterized in that, The support base has an annular cavity that fits into the lower end of the mixing tank, and a heater and a temperature sensor for processing and detecting the heat exchange medium are installed in the annular cavity. A stopper is rotatably connected to the upper center of the mixing tank. A drive assembly for rotating the stopper is provided on the mixing tank. A serpentine heat exchange tube is provided in the mixing tank, with both ends of the serpentine heat exchange tube passing through the stopper. A cylindrical body is fixedly provided directly above the stopper. A circular plate is rotatably connected to the lower opening of the cylindrical body. A pipe port connecting sleeve is provided at the inner center of the cylindrical body. One end of the serpentine heat exchange tube passes through the circular plate and is rotatably connected to the pipe port connecting sleeve, while the other end passes through the circular plate and communicates with the inside of the cylindrical body. A first infusion tube communicating with an annular cavity is connected to the pipe port connecting sleeve, and a circulation pump is provided on the first infusion tube. A second infusion tube communicating with the annular cavity is connected to the cylindrical body.

2. The mixing apparatus for preparing automotive urea according to claim 1, characterized in that, Each bend of the serpentine heat exchange tube is connected to a mixing liquid agitation assembly. The mixing liquid agitation assembly includes a connecting pipe body connected to the serpentine heat exchange tube. A rotating shaft extending from both sides of the connecting pipe body is rotatably connected in the connecting pipe body. An impeller is provided on the rotating shaft located inside the connecting pipe body, and agitation blades are connected on the rotating shaft located outside the connecting pipe body.

3. The mixing device for preparing automotive urea according to claim 2, characterized in that, Multiple of the aforementioned mixture agitation components are staggered vertically on each bend of the serpentine heat exchange tube.

4. The mixing apparatus for preparing automotive urea according to claim 1, characterized in that, The mixing tank is also provided with a first measuring cylinder and a second measuring cylinder on both sides. The lower ends of the first measuring cylinder and the second measuring cylinder are connected to a feeding pipe that communicates with the mixing tank. The lower end of the mixing tank is connected to a discharge pipe. Both the feeding pipe and the discharge pipe are equipped with valves.

5. The mixing apparatus for preparing automotive urea according to claim 1, characterized in that, A sealed bearing is provided at the center of the upper end of the mixing tank, and the plunger is inserted into the sealed bearing.

6. The mixing apparatus for preparing automotive urea according to claim 1 or 5, characterized in that, The drive assembly includes a first gear connected to the upper end of the plunger and a mixing motor fixed on the mixing tank. A second gear that meshes with the first gear is connected to the output shaft of the mixing motor.

7. The mixing apparatus for preparing automotive urea according to claim 1, characterized in that, The support includes a base and several legs, with the legs connected to the lower surface of the base, and the annular cavity formed in the base.

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