Chemical stirring tank
The chemical stirring tank integrates mixing and reflux systems to achieve uniform polyurethane mixing, addressing non-uniformity issues and reducing equipment costs and space, enhancing production efficiency and quality.
Patent Information
- Application Number
- CN202421031440.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-13
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-13
AI Technical Summary
Existing polyurethane production processes require multiple tanks for stirring and temperature control, leading to non-uniform mixing, increased equipment costs, and difficulty in maintaining consistent mixture ratios, which affects product quality.
A chemical stirring tank with integrated mixing and reflux systems, including a diaphragm pump and electromagnetic valves, ensures uniform mixing by recirculating non-uniform mixtures until quality standards are met, reducing the need for multiple tanks and enabling accurate ratio control.
Ensures uniform mixing, reduces equipment costs and space, and facilitates accurate ratio control, thereby improving product quality and efficiency in polyurethane production.
Smart Images
Figure CN222240039U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of liquid polyurethane resin production, in particular to a chemical stirring tank. Background Art
[0002] Polyurethane is a type of polymer made by the reaction of isocyanate (or polyol) with various amines, polyols, etc. Among them, liquid polyurethane has high viscosity and is mainly used in insulation, waterproofing, bonding, caulking and other application fields.
[0003] Liquid polyurethane usually refers to polyurethane prepared by the reaction of two monomers (referred to as liquid polyurethane). During the preparation process, isocyanate and polyol are mixed in a certain proportion. The production process of liquid polyurethane is as follows: ① Mix isocyanate and polyol in a certain proportion and stir evenly; ② Add catalysts and additives to the mixture, and use the heating system to heat the mixture for a period of time; ③ Turn off the heating system and continue stirring until the mixture cools to room temperature; ④ Continue to add a certain amount of solvent to the mixture and continue stirring; ⑤ Filter the mixture to remove impurities and insoluble substances; ⑥ Color and fragrance the mixture. As for the current production status of the factory, step ① is performed in a stirring tank, while steps ②, ③ and ④ are performed in a temperature control tank. After step ① is completed, the mixture needs to be transported to the temperature control tank as a whole with the help of a liquid pump. This means that the liquid polyurethane production line needs to be equipped with a stirring tank and a temperature control tank at the same time. In this way, on the one hand, after the mixture is stirred, it often fails to meet the uniformity quality inspection standard. The reason is that the density values of the components that make up the mixture are quite different, and the properties are different. Due to improper stirring methods, stratification is very likely to occur, which leads to insufficient communication and integration. On the other hand, it is necessary to purchase multiple sets of equipment with different functions, which increases the equipment purchase cost and occupies a large area, which is not conducive to workshop planning and layout. On the other hand, the mixture needs to be circulated between multiple tanks with different functions, and it is difficult to accurately control its ratio during the circulation process, which is bound to affect the quality of the finished liquid polyurethane. Therefore, it is urgent for technicians to solve the above problems. Summary of the invention
[0004] Therefore, in view of the above existing problems and defects, the project team of the present utility model collected relevant information, conducted multiple evaluations and considerations, and the project team members continuously experimented and modified, which eventually led to the emergence of the chemical mixing tank.
[0005] In order to solve the above technical problems, the utility model relates to a chemical stirring tank suitable for preparing polyurethane, comprising a tank body, a first feeding pipe, a second feeding pipe, a third feeding pipe and a stirring system. Among them, a mixing chamber is arranged in the tank body to receive a polyurethane initial liquid mixed with an isocyanate solution delivered through the first feeding pipe, a polyol solution delivered through the second feeding pipe and a catalyst or auxiliary agent fed through the third feeding pipe. The stirring system is used to disturb the mixing chamber, which is carried by the tank body. In addition, the chemical stirring tank also includes a reflux system. After preliminary stirring, the initial polyurethane liquid that has not yet reached the uniformity standard is pumped back into the mixing chamber through the reflux system. At the same time, the stirring system continues to work until the mixing uniformity of the initial polyurethane liquid reaches the standard.
[0006] As a further improvement of the technical solution disclosed in the utility model, the reflux system includes a diaphragm pump, a pump-out pipe unit, a liquid return pipe unit and a bypass pipe unit. The polyurethane initial liquid is pumped from the mixing chamber to the inner cavity of the diaphragm pump via the pump-out pipe unit, and under the continuous action of the pumping force from the diaphragm pump, the polyurethane initial liquid whose uniformity is not up to standard is pumped back to the mixing chamber via the liquid return pipe unit, and the polyurethane initial liquid whose uniformity is up to standard is pumped to the filtering device via the bypass pipe unit.
[0007] As a further improvement of the technical solution disclosed in the utility model, the pump-out pipe unit includes a pump-out pipe and a first electromagnetic stop valve. The liquid return pipe unit includes a liquid return pipe and a second electromagnetic stop valve. The bypass pipe unit includes a bypass pipe and a third electromagnetic stop valve. The pump-out pipe used to pump the polyurethane initial liquid and the liquid return pipe used to pump back the polyurethane initial liquid whose uniformity has not yet reached the standard are respectively connected to the inlet and outlet of the diaphragm pump in a one-to-one correspondence. The bypass pipe used to pump the polyurethane initial liquid whose uniformity has reached the standard is connected to the liquid return pipe.
[0008] As a further improvement of the technical solution disclosed in the utility model, the chemical stirring tank also includes a heating system. The heating system is used to heat the polyurethane initial liquid, and it is matched with the reflux system. The heating system includes a first high-frequency electric heating coil mounted on the return liquid pipe and a second high-frequency electric heating coil mounted on the pump outlet pipe.
[0009] As a further improvement of the technical solution disclosed in the utility model, the stirring system includes a reduction motor, a transmission shaft and a stirring assembly. The reduction motor is installed on the top wall of the tank body. The transmission shaft is driven by the reduction motor and vertically inserted into the mixing chamber. The stirring assembly is sleeved on the transmission shaft.
[0010] As a further improvement of the technical solution disclosed in the utility model, the stirring assembly includes a pair of split-type mounting sleeves, stirring blades and stabilizing ribs. A plurality of stirring blades are inserted into the split-type mounting sleeve and are evenly distributed circumferentially around the central axis of the split-type mounting sleeve. The number of stabilizing ribs is consistent with the number of stirring blades, and is welded between two adjacent stirring blades.
[0011] As a further improvement of the technical solution disclosed in the utility model, the stirring system also includes an anti-sway seat. The anti-sway seat is used to limit the circumferential swing freedom of the transmission shaft, and is installed on the bottom wall of the tank. The anti-sway seat includes a seat body and a radial bearing embedded in the seat body and fitted with the transmission shaft.
[0012] As a further improvement of the technical solution disclosed in the utility model, the lower half of the seat body is a hollow structure, and a plurality of long strip-shaped liquid discharge gaps are evenly distributed around the circumference of its side wall to connect the reflux system with the mixing chamber.
[0013] In actual applications, the initial liquid polyurethane does not need to be pumped and transferred, and the initial mixing of isocyanate and polyol, catalyst and additive addition can be completed in the same tank in sequence. And under the action of the reflux system, the initial polyurethane liquid that has undergone initial stirring and has not yet reached the uniformity standard needs to be pumped back into the mixing chamber for secondary stirring to ensure that the uniformity of the final discharged initial polyurethane liquid meets the quality inspection standards.
[0014] In the factory production stage, the chemical stirring tank disclosed in the utility model can at least achieve the following beneficial technical effects, specifically:
[0015] 1) During the mixing process, the uniformity of the pre-discharged liquid polyurethane initial state is tested in real time. Only when its uniformity meets the standard (meets the quality inspection standard requirements) will it be discharged through the chemical mixing tank to enter the next process. If the uniformity does not meet the standard, the liquid polyurethane initial state needs to be pumped back to the mixing chamber through the reflux system and continue to be stirred and disturbed until its uniformity meets the standard, which lays a good foundation for improving the quality of the liquid polyurethane finished product;
[0016] 2) The equipment required for the liquid polyurethane production line has been greatly reduced, which not only effectively reduces the equipment purchase cost, but also reduces the floor space, which is conducive to the subsequent workshop planning and layout;
[0017] 3) The liquid polyurethane initial state does not need to flow between multiple tanks with different functions, so it is easy to accurately control its ratio. Moreover, due to the consistent storage environment, the capacity and concentration of the liquid polyurethane initial state remain constant, which is conducive to more accurate addition of catalysts, additives, and solvents in the subsequent process. Therefore, the liquid polyurethane resin preparation process can be accurately implemented, which is convenient for improving the quality of the finished product. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0019] Figure 1 It is a three-dimensional schematic diagram of the chemical stirring tank disclosed in the utility model (after hiding part of the tank wall).
[0020] Figure 2 yes Figure 1 Front view of .
[0021] Figure 3 The utility model is a three-dimensional schematic diagram of a stirring system in a chemical stirring tank disclosed by the utility model.
[0022] Figure 4 yes Figure 3 Front view of .
[0023] Figure 5 The utility model is a three-dimensional schematic diagram of a stirring assembly in a chemical stirring tank disclosed by the utility model.
[0024] Figure 6 The utility model is a three-dimensional schematic diagram of an anti-sway seat in a chemical stirring tank disclosed by the utility model.
[0025] Figure 7 The utility model is a three-dimensional schematic diagram of a reflux system in a chemical stirring tank disclosed by the utility model.
[0026] 1-tank body; 11-mixing chamber; 2-first feeding pipe; 3-second feeding pipe; 4-third feeding pipe; 5-stirring system; 51-reduction motor; 52-drive shaft; 53-stirring assembly; 531-split mounting sleeve; 532-stirring blade; 533-stable rib plate; 54-anti-sway seat; 541-seat body; 5411-long strip drainage gap; 542-radial bearing; 6-reflux system; 61-diaphragm pump; 62-pump outlet pipe unit; 621-pump outlet pipe; 622-first electromagnetic stop valve; 63-return liquid pipe unit; 631-return liquid pipe; 632-second electromagnetic stop valve; 64-bypass pipe unit; 641-bypass pipe; 642-third electromagnetic stop valve; 7-heating system; 71-first high-frequency electric heating coil; 72-second high-frequency electric heating coil. DETAILED DESCRIPTION
[0027] In the description of the present invention, it should be understood that the terms "front", "rear", "up", "down", "left", "right", etc., indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.
[0028] The following is a further detailed description of the contents disclosed in the present utility model in conjunction with specific embodiments. Figure 1 , Figure 2 The three-dimensional schematic diagram and the front view of the chemical stirring tank disclosed in the utility model are respectively shown. It can be seen that it is mainly composed of several parts such as a tank body 1, a first feeding pipe 2, a second feeding pipe 3, a third feeding pipe 4, a stirring system 5 and a reflux system 6. Among them, the tank body is made of stainless steel with excellent corrosion resistance, and a mixing chamber 11 is arranged therein. During the preparation, isocyanate solution, polyol solution, catalyst or auxiliary agent are input into the mixing chamber 11 through the first feeding pipe 2, the second feeding pipe 3, and the third feeding pipe 4 according to the specific process. The stirring system 5 is used to disturb the mixing chamber, which is carried by the tank body 1. After preliminary stirring, the polyurethane initial liquid that has not yet reached the uniformity standard is pumped back into the mixing chamber through the reflux system 6. At the same time, the stirring system 5 continues to work until the mixing uniformity of the polyurethane initial liquid reaches the standard.
[0029] like Figure 7 As shown in the figure, the reflux system 6 includes a diaphragm pump 61, a pump outlet pipe unit 62, a liquid return pipe unit 63 and a bypass pipe unit 64. The pump outlet pipe unit 62 includes a pump outlet pipe 621 and a first electromagnetic stop valve 622. The liquid return pipe unit 63 includes a liquid return pipe 631 and a second electromagnetic stop valve 632. The bypass pipe unit 64 includes a bypass pipe 641 and a third electromagnetic stop valve 642. During the production process, in the mixing chamber 11, the polyurethane initial liquid that has undergone preliminary mixing is sent to the inner cavity of the diaphragm pump 61 through the pump outlet pipe 621 (the first electromagnetic stop valve 622 remains in an open state), and under the continuous action of the pumping force from the diaphragm pump 61, the polyurethane initial liquid whose uniformity is not up to standard is pumped back to the mixing chamber 11 through the return pipe 631 (the second electromagnetic stop valve 622 remains in an open state, and the third electromagnetic stop valve 642 remains in a closed state), and the polyurethane initial liquid whose uniformity is up to standard is pumped to the next process equipment through the bypass pipe 641 (the third electromagnetic stop valve 642 remains in an open state, and the second electromagnetic stop valve 632 remains in a closed state) to execute the subsequent process route.
[0030] In practical applications, the liquid polyurethane initial state does not need to be pumped and transferred, and the initial mixing of isocyanate and polyol, catalyst and auxiliary agent addition processes can be completed in the same tank in sequence. And under the action of the reflux system 6, the initial polyurethane liquid that has undergone initial stirring and has not yet reached the uniformity standard needs to be pumped back into the mixing chamber 11 for secondary stirring to ensure that the uniformity of the final discharged initial polyurethane liquid meets the quality inspection standard.
[0031] In the factory production stage, the chemical stirring tank disclosed in the utility model can at least achieve the following beneficial technical effects, specifically:
[0032] 1) During the stirring process, the uniformity of the pre-discharged liquid polyurethane initial state is tested in real time. Only when its uniformity meets the standard (meets the quality inspection standard requirements) is it discharged through the chemical stirring tank to enter the next process. When the uniformity does not meet the standard, the liquid polyurethane initial state needs to be pumped back to the mixing chamber 11 through the reflux system to continue to be stirred and disturbed until its uniformity meets the standard, which lays a good foundation for improving the quality of the liquid polyurethane finished product;
[0033] 2) The equipment required for the liquid polyurethane production line has been greatly reduced, which not only effectively reduces the equipment purchase cost, but also reduces the floor space, which is conducive to the subsequent workshop planning and layout;
[0034] It should also be noted here that the liquid polyurethane initial state does not need to flow between multiple tanks with different functions, so it is easy to accurately control its ratio, and because the storage environment is consistent, the capacity and concentration of the liquid polyurethane initial state remain constant, which is conducive to more accurate addition of catalysts, additives, and solvents in the subsequent process, and thus the liquid polyurethane resin preparation process can be accurately implemented, which is convenient for improving the quality of the finished product.
[0035] like Figure 3 , 4 As shown in , the stirring system 5 is mainly composed of a reduction motor 51, a transmission shaft 52 and a stirring assembly 53. Among them, the reduction motor 51 is installed on the top wall of the tank body 1. The transmission shaft 52 is driven by the reduction motor 51 and vertically inserted into the mixing chamber 11. The stirring assembly 53 is sleeved on the transmission shaft 52. During the operation of the chemical stirring tank, the stirring assembly 53 continuously performs circumferential rotation due to the torque, and the polyurethane initial liquid is pushed upward from a lower position due to the external force, and at the same time, it is subjected to the pulling force and cutting force, thereby achieving the mixing of the substances. And this alternating pushing and shearing process will accelerate the mixing speed.
[0036] During the trial operation, the stirring assembly 53 is an integral outsourced component, and the multiple stirring blades are arranged in a petal shape and lack effective connection with each other. Therefore, in actual operation, the stirring blades vibrate severely and their service life is seriously shortened. For this reason, in this embodiment, the stirring assembly 53 is optimized and redesigned, that is, Figure 5 As shown in the figure, the stirring assembly 53 is a combined design structure, which includes a split-type mounting sleeve 531, stirring blades 532 and a stabilizing rib plate 533. Six stirring blades 532 are inserted into the split-type mounting sleeve 531 and are evenly distributed circumferentially around the central axis of the split-type mounting sleeve 531. The number of stabilizing rib plates 533 is also 6, and they are welded between two adjacent stirring blades 532.
[0037] However, in the actual production process, workers found that the chemical mixing tank vibrated severely and made a lot of noise during operation. The reason for this is that, because the mixing system 5 is of conventional design and the drive shaft 52 is fixed in a single bearing seat (that is, a bearing seat is provided near the reduction motor 51), its lower end lacks effective freedom restriction measures, which causes the circumferential swing amplitude of its free end to exceed the standard during the continuous disturbance of the polyurethane initial liquid. In view of this, as a further optimization of the above technical solution, the mixing system 5 is additionally provided with an anti-sway seat 54. The anti-sway seat 54 is used to limit the circumferential swing freedom of the drive shaft 52, and it is installed on the bottom wall of the tank body 1. The anti-sway seat 54 includes a seat body 541 and a radial bearing 542 (such as a seat body 541) embedded in the seat body 541 and fitted with the drive shaft 42. Figure 6 ).
[0038] Furthermore, by Figure 6 It can also be clearly seen from the figure that the lower half of the seat body 541 is a hollow structure, and a plurality of long strip-shaped drainage gaps 5411 are evenly distributed around the side wall thereof, connecting the pump-out pipe 621 with the mixing chamber 11. During the operation of the chemical stirring tank, the polyurethane initial liquid flows to the pump-out pipe 621 through the plurality of long strip-shaped drainage gaps 5411, thus effectively avoiding the occurrence of the phenomenon that the reflux system 6 is blocked or the flow rate is reduced due to the intrusion of large foreign objects.
[0039] Finally, it should be noted that according to the process requirements, temperature has a very important influence on the formation of polyurethane initial solution and mixing uniformity. If the temperature does not meet the design requirements, it will not only seriously affect the mixing speed of isocyanate and polyol, but also reduce the chemical activity of subsequent catalysts and additives. In view of this, as a further optimization of the above technical solution, Figure 7As shown in the figure, the reflux system 6 is also equipped with a heating system 7. The heating system 7 is used to heat up the polyurethane initial liquid, and includes a first high-frequency electric heating coil 71 mounted on the return liquid pipe 631 and a second high-frequency electric heating coil 72 mounted on the pump-out pipe 621. During the operation of the chemical stirring tank, the initial polyurethane liquid continuously circulates in the reflux system 6. The first high-frequency electric heating coil 71 and the second high-frequency electric heating coil 72 continuously heat the walls of the pump-out pipe 621 and the return liquid pipe 631 under the action of high-frequency current. The initial polyurethane liquid is heated to the expected temperature due to the continuous input of heat, which is conducive to improving its mixing speed and mixing uniformity.
[0040] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A chemical stirring tank, suitable for preparing polyurethane, comprising a tank body, a first feeding pipe, a second feeding pipe, a third feeding pipe and a stirring system; wherein: A mixing chamber is arranged in the tank body to receive the isocyanate solution delivered through the first feeding pipe, the polyol solution delivered through the second feeding pipe, and the catalyst or auxiliary agent fed through the third feeding pipe to form a mixture of polyurethane initial liquid; the stirring system is used to disturb the mixing chamber, which is carried by the tank body, and is characterized in that it also includes a reflux system; the polyurethane initial liquid that has undergone preliminary stirring and has not yet reached the uniformity standard is pumped back into the mixing chamber through the reflux system, and at the same time, the stirring system continues to work until the mixing uniformity of the polyurethane initial liquid reaches the standard.
2. The chemical stirring tank according to claim 1, characterized in that: The reflux system includes a diaphragm pump, a pump-out pipe unit, a liquid return pipe unit and a bypass pipe unit; the polyurethane initial liquid is pumped from the mixing chamber to the inner cavity of the diaphragm pump via the pump-out pipe unit, and under the continuous action of the pumping force from the diaphragm pump, the polyurethane initial liquid whose uniformity is not up to standard is pumped back to the mixing chamber via the liquid return pipe unit, while the polyurethane initial liquid whose uniformity is up to standard is pumped to the filtering device via the bypass pipe unit.
3. The chemical stirring tank according to claim 2, characterized in that: The pump-out pipe unit includes a pump-out pipe and a first electromagnetic stop valve; the liquid return pipe unit includes a liquid return pipe and a second electromagnetic stop valve; the bypass pipe unit includes a bypass pipe and a third electromagnetic stop valve; the pump-out pipe used for pumping polyurethane initial liquid and the liquid return pipe used for pumping back polyurethane initial liquid whose uniformity has not yet reached the standard are respectively connected to the inlet and outlet of the diaphragm pump in a one-to-one correspondence; the bypass pipe used for pumping polyurethane initial liquid whose uniformity has reached the standard is bypass-connected to the liquid return pipe.
4. The chemical stirring tank according to claim 3, characterized in that: It also includes a heating system; the heating system is used to heat the polyurethane initial liquid, and it is matched with the reflux system; the heating system includes a first high-frequency electric heating coil mounted on the return liquid pipe and a second high-frequency electric heating coil mounted on the pump outlet pipe.
5. The chemical stirring tank according to any one of claims 1 to 4, characterized in that: The stirring system includes a reduction motor, a transmission shaft and a stirring assembly; the reduction motor is installed on the top wall of the tank; the transmission shaft is driven by the reduction motor and vertically inserted into the mixing chamber; The stirring component is sleeved on the transmission shaft.
6. The chemical stirring tank according to claim 5, characterized in that: The stirring assembly includes a pair of split mounting sleeves, stirring blades and stabilizing ribs; a plurality of the stirring blades are inserted into the split mounting sleeves and are evenly distributed circumferentially around the central axis of the split mounting sleeves; the number of the stabilizing ribs is consistent with the number of the stirring blades, and they are welded between two adjacent stirring blades.
7. The chemical stirring tank according to claim 5, characterized in that: The stirring system also includes an anti-sway seat; the anti-sway seat is used to limit the circumferential swing freedom of the transmission shaft, and is installed on the bottom wall of the tank body; the anti-sway seat includes a seat body and a radial bearing embedded in the seat body and fitted with the transmission shaft.
8. The chemical stirring tank according to claim 7, characterized in that: The lower half of the seat body is a hollow structure, and a plurality of long strip-shaped liquid discharge gaps are evenly distributed around the side wall thereof to connect the reflux system with the mixing chamber.