Preparation device for VAE emulsion

Abstract

The invention discloses a preparation device for VAE emulsion, which comprises a heat exchanger, the inlet end of the heat exchanger is connected with an inlet valve, the outlet end of the heat exchanger is connected with an outlet valve, the preparation device further comprises a cleaning device, and the cleaning device comprises a cleaning solvent heater and a cleaning solvent circulating pump. And the cleaning solvent heater, the cleaning solvent circulating pump and the heat exchanger are connected in series. According to the scheme, the problems that in the prior art, when a heat exchanger of a preparation device is poor in heat exchange, maintenance operation is tedious, and labor intensity is high are solved.

Description

Technical Field

[0001] The present invention relates to a preparation device for VAE emulsion. Background Art

[0002] VAE emulsion (vinyl acetate-ethylene copolymer) is a copolymer formed by copolymerizing vinyl acetate and ethylene monomers. It was first industrially produced by Air Products and Chemicals, Inc. in the mid-1960s. Since its inception, due to its excellent performance, VAE emulsion has shown great vitality and has been widely used in many fields such as adhesives, coatings, paper processing, fabric processing, packaging, and construction. Since emulsion polymerization is a polymerization method in which isolated latex particles are formed according to the micelle mechanism or oligomer mechanism in an emulsion using water or other liquids as a medium, and free radical addition polymerization or ionic addition polymerization is carried out therein to produce a polymer.

[0003] Currently, heat exchangers are used in VAE emulsion preparation devices. The role of the heat exchanger is to preheat the material with hot water during the reaction heating stage, and after the reaction starts, the reaction heat is removed by circulating cooling water below 30°C. The heat exchanger is generally a fixed tube-sheet heat exchanger. During the production process, when the heat transfer of the heat exchange system deteriorates, the heat exchange temperature difference is very small, the batch reaction time is too long, and the product filter residue increases greatly, making it difficult to continue production, the heat exchanger must be switched. The heat exchanger with poor heat exchange needs to be disassembled from the preparation device for high-pressure water flushing and maintenance, and then reassembled back into the preparation device after cleaning. As the number of disassembly and assembly of the heat exchanger increases, leakage problems are likely to occur at the connection of the heat exchanger, thus affecting the operation of the entire preparation device. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation device for VAE emulsion to solve the problems of cumbersome maintenance operation and high labor intensity when the heat exchanger of the existing preparation device has poor heat exchange.

[0005] To achieve the above object, the basic solution of the present invention provides a preparation device for VAE emulsion, including a heat exchanger, an inlet valve is connected to the inlet end of the heat exchanger, an outlet valve is connected to the outlet end of the heat exchanger, and a cleaning device is further included. The cleaning device includes a cleaning solvent heater and a cleaning solvent circulation pump, and the cleaning solvent heater, the cleaning solvent circulation pump and the heat exchanger are connected in series.

[0006] The beneficial effect of this basic solution is that when it is found that the heat transfer of the heat exchange system deteriorates, the inlet valve and the outlet valve are closed, and the cleaning solvent circulation pump is used to drive the cleaning solvent to circulate between the cleaning solvent circulation pump, the cleaning solvent heater and the heat exchanger, so as to finally restore the heat exchange performance of the heat exchanger and make the heat exchange system return to normal operation. There is no need to disassemble the equipment, which reduces the labor intensity and makes the maintenance operation of the preparation device simple and easy.

[0007] Furthermore, a circulation pump discharge valve is provided between the cleaning solvent heater and the cleaning solvent circulation pump. A cleaning solvent discharge pipe is provided between the circulation pump discharge valve and the cleaning solvent circulation pump, and a discharge valve is installed on the cleaning solvent discharge pipe. With such a setting, by closing the circulation pump discharge valve, the cleaning solvent can be discharged from the cleaning solvent discharge pipe, thus facilitating the discharge of the cleaning solvent.

[0008] Furthermore, a cleaning solvent addition port is provided at the feed end of the cleaning solvent heater, and an addition port valve is provided at the cleaning solvent addition port. With such a setting, it is convenient for the cleaning solvent to quickly enter the cleaning solvent heater and be heated after the cleaning solvent is added, which is beneficial to improving the cleaning effect on the heat exchanger.

[0009] Furthermore, the cleaning solvent heater is a heat medium heater. With such a setting, it is convenient to use the heat medium generated by the preparation device for heating, without the need to separately set a heat source, which is beneficial to reducing energy consumption.

[0010] Furthermore, the heat medium heater is a steam heater. With such a setting, the steam heater uses steam for heating. Compared with other heat media, steam is safer and more environmentally friendly, and there is no need to worry about other problems during use.

[0011] Furthermore, the cleaning solvent heater is an electric heater. With such a setting, the electric heater only needs to be connected to the power supply during use, which is beneficial to making the operation simpler and more convenient.

[0012] Furthermore, an evaporation kettle is connected to the cleaning solvent discharge pipe. With such a setting, it is convenient to recover methanol in the cleaning solvent by using the evaporation kettle, thereby reducing raw material consumption and lowering the use cost. Description of the Drawings

[0013] Figure 1 This is a schematic diagram of an embodiment of a preparation device for VAE emulsion according to the present invention. Detailed Embodiments

[0014] The following is a further detailed description through specific embodiments: The reference numerals in the drawings of the specification include: inlet valve 1, heat exchanger 2, outlet valve 3, cleaning solvent heater 4, cleaning solvent addition port 5, circulation pump discharge valve 6, evaporation kettle 7, discharge valve 8, cleaning solvent circulation pump 9.

[0015] The embodiment is basically as shown in the attached Figure 1Shown: A preparation device for VAE emulsion, including a heat exchanger 2. The inlet end of the heat exchanger 2 is connected with an inlet valve 1, and the outlet end of the heat exchanger 2 is connected with an outlet valve 3. For the convenience of valve installation, the inlet end of the heat exchanger 2 is connected with the inlet valve 1 through an inlet pipe, and the outlet end of the heat exchanger 2 is connected with the outlet valve 3 through an outlet pipe.

[0016] This preparation device also includes a cleaning device, which is located between the inlet valve 1 and the outlet valve 3. The cleaning device includes a cleaning solvent heater 4 and a cleaning solvent circulation pump 9. The cleaning solvent heater 4, the cleaning solvent circulation pump 9 and the heat exchanger 2 are connected in series, so that the cleaning solvent can circulate among the three of them. Specifically, the discharging end of the cleaning solvent heater 4 is connected with the inlet pipe at the inlet end of the heat exchanger 2, the feeding end of the cleaning solvent circulation pump 9 is connected with the outlet pipe at the outlet end of the heat exchanger 2, and the discharging end of the cleaning solvent circulation pump 9 is connected with the feeding end of the cleaning solvent heater 4. In this embodiment, the cleaning solvent heater 4 is a heat medium heater, which uses various liquid or gas media with heat for heating, such as a steam heater heated by steam. Of course, in other embodiments, the cleaning solvent heater 4 can also be an electric heater.

[0017] A circulation pump discharge valve 6 is arranged between the cleaning solvent heater 4 and the cleaning solvent circulation pump 9. A cleaning solvent discharge pipe is arranged between the circulation pump discharge valve 6 and the cleaning solvent circulation pump 9, and a discharge valve 8 is installed on the cleaning solvent discharge pipe. Through such a setting, when the circulation pump discharge valve 6 is closed and the discharge valve 8 is opened, the cleaning solvent will enter the cleaning solvent discharge pipe after coming out of the cleaning solvent circulation pump 9, so that the cleaning solvent no longer performs the circulating cleaning operation. In this embodiment, an evaporation kettle 7 is connected to the cleaning solvent discharge pipe, which is convenient for collecting the cleaning solvent and recovering methanol, thereby reducing the consumption of methanol. A cleaning solvent addition port 5 is arranged at the feeding end of the cleaning solvent heater 4, and an addition port valve is arranged at the cleaning solvent addition port 5, which is convenient for the cleaning solvent to quickly enter the cleaning solvent heater 4 for heating, so as to improve the cleaning effect.

[0018] The specific implementation process is as follows: When it is found that the heat transfer of the heat exchange system deteriorates, close the inlet valve 1 and the outlet valve 3, and keep the discharge valve 8 on the cleaning solvent discharge pipe in the closed state. Then start the cleaning solvent circulation pump 9, add the cleaning solvent into the cleaning solvent heater 4 from the cleaning solvent addition port 5 and be heated, and under the action of the cleaning solvent circulation pump 9, the heated cleaning solvent enters the heat exchanger 2, so as to realize the cleaning of the heat exchanger 2. As the cleaning solvent circulates (the direction of the arrow in the figure is the flow direction of the cleaning solvent), until the heat exchange performance of the heat exchanger 2 is restored.

[0019] The above are only embodiments of the present invention, and common general knowledge of specific structures and characteristics in the solution is not described in detail herein. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent.

Claims

1. A preparation device for VAE emulsion, comprising a heat exchanger, an inlet valve is connected to the inlet end of the heat exchanger, and an outlet valve is connected to the outlet end of the heat exchanger. Characterized in that: It further comprises a cleaning device, the cleaning device includes a cleaning solvent heater and a cleaning solvent circulation pump, and the cleaning solvent heater, the cleaning solvent circulation pump and the heat exchanger are connected in series.

2. The preparation device for VAE emulsion according to claim 1, Characterized in that: A circulation pump discharge valve is arranged between the cleaning solvent heater and the cleaning solvent circulation pump, a cleaning solvent discharge pipe is arranged between the circulation pump discharge valve and the cleaning solvent circulation pump, and a discharge valve is installed on the cleaning solvent discharge pipe.

3. The preparation device for VAE emulsion according to claim 2, Characterized in that: A cleaning solvent addition port is arranged at the feed end of the cleaning solvent heater, and an addition port valve is arranged at the cleaning solvent addition port.

4. The preparation device for VAE emulsion according to claim 3, Characterized in that: The cleaning solvent heater is a heat medium heater.

5. The preparation device for VAE emulsion according to claim 4, Characterized in that: The heat medium heater is a steam heater.

6. The preparation device for VAE emulsion according to claim 3, Characterized in that: The cleaning solvent heater is an electric heater.

7. The preparation device for VAE emulsion according to claim 2, Characterized in that: An evaporation kettle is connected to the cleaning solvent discharge pipe.

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