A reaction kettle for preparing viscoelastic polymer emulsion

Abstract

The utility model relates to a reactor for preparing a viscoelastic polymer emulsion. The reactor effectively prevents local uneven mixing, avoids the formation of dead zones or local uneven mixing in the reactor, and helps to ensure the uniform progress of the reaction. The structure adopted by the utility model includes a mixing kettle, a reactor body and a constant temperature heating / refrigeration device. The reactor body is a sleeve type, and the sleeve is connected to the cold / hot medium inlet and outlet of the constant temperature heating / refrigeration device through a pipeline. The mixing kettle is connected to the inner cavity of the reactor body through a pipeline; an initiator feeding pipe and a nitrogen inlet are arranged on the reactor body, and a plurality of dispersion baffles are evenly arranged inside. Sensors are arranged on the dispersion baffles, and porous spray heads are evenly arranged on the initiator feeding pipe extending into the reactor body. A check valve is arranged at the inlet end of the porous spray head, and a temperature sensor is also arranged in the reactor body.

Description

Technical Field

[0001] The utility model relates to a reaction kettle, in particular to a reaction kettle for preparing viscoelastic polymer emulsion. Technical Background

[0002] Inverse emulsion polymerization is one of the ideal methods to obtain high molecular weight polymers and is particularly suitable for large-scale batch production of polymer emulsions.

[0003] In recent years, the fracturing fluid thickener of inverse emulsion polymerization has the characteristics of high molecular weight, long molecular chain, fast dissolution rate, etc. It is used in different fracturing construction sites, is easy to operate, can effectively improve construction efficiency, and has broad application prospects in large-scale fracturing sites. Therefore, the application of inverse emulsion polymers in fracturing fluids has gradually gained attention. In the process of inverse emulsion polymerization, as the reaction proceeds, the viscosity of the entire system will change, and the initiator will be unevenly dispersed when added, resulting in a local temperature increase, resulting in an implosion phenomenon. Or as the probe of the thermometer is blocked during the reaction and the temperature of the system cannot be sensed in time, when the temperature of the system is collected, the amount of initiator has been used, and the temperature cannot be controlled. At the same time, the inverse emulsion polymerization process is long, and continuous stirring is required throughout the process. Both the low-speed stirring motor and the high-speed stirring motor have heat dissipation during the working process. Long-term operation will cause the motor to short-circuit due to untimely heat dissipation, and the motor life will be shortened.

[0004] When synthesizing viscoelastic polymers for fracturing fluids, the introduced functional monomers have a certain steric hindrance effect during the polymerization process. Therefore, the selection and addition method of the initiator are particularly critical. The announcement number is "CN207507472 U" and the patent name is "A polymer emulsion synthesis reaction system". It discloses a polymer emulsion synthesis reaction system. The problem is that it is not designed to introduce nitrogen to improve the deoxygenation efficiency and initiation efficiency, and it is not designed to consider the sudden change of system viscosity during the inverse emulsion polymerization process. Different initiator addition methods lead to local temperature increases and even the occurrence of implosion. Summary of the invention

[0005] In view of this, the purpose of the utility model is to overcome the problems of difficulty in achieving staged controlled stirring in existing reactors and gel and adhesion problems caused by high temperature, and to provide a reactor suitable for the preparation of viscoelastic polymer emulsions to meet the production of viscoelastic polymer emulsions required in fracturing fluids, and can be widely used in the production of other inverse emulsion polymers.

[0006] The technical solution adopted by the utility model is: a reaction kettle for preparing viscoelastic polymer emulsion, comprising a mixing kettle, a reaction kettle body and a constant temperature heating / refrigeration device, the reaction kettle body is a sleeve type, the sleeve is connected to the cold / hot medium inlet and the cold / hot medium outlet of the constant temperature heating / refrigeration device through a pipeline, and the mixing kettle is connected to the inner cavity of the reaction kettle body through a pipeline;

[0007] The reactor body is provided with an initiator feeding pipe and a nitrogen inlet, and a plurality of dispersion baffles are evenly arranged inside. The dispersion baffles are provided with sensors. The initiator feeding pipe extending into the reactor body is evenly provided with porous spray heads, and a check valve is provided at the inlet end of the porous spray head. A temperature sensor is also provided in the reactor body.

[0008] Furthermore, a sight glass is also provided on the reactor body.

[0009] Furthermore, a mixing agitator is arranged in the mixing kettle, and the stirring paddle arranged on the mixing agitator is a frame-type stirring paddle.

[0010] Furthermore, a raw material discharge valve and a material injection pump are provided on the pipeline connecting the mixing kettle and the reaction kettle body.

[0011] Furthermore, a discharge valve is also provided at the tail of the reactor body.

[0012] Furthermore, the constant temperature heating / refrigeration device is provided with a heating switch, a cooling switch, a temperature display and a constant temperature heating / refrigeration device switch.

[0013] Beneficial effects of the utility model:

[0014] 1. The reactor of the utility model adopts a sleeve type, and the temperature required by the reaction system is controlled by a constant temperature heating / cooling device, which can effectively control the reaction temperature, ensure the smooth progress of the reaction process, reduce the temperature rise caused by self-acceleration of the reaction, and avoid explosion, gelation or sticking of the reactor.

[0015] 2. A check valve is provided on the initiator feeding pipe of the utility model to prevent the backflow of the feed liquid, and a multi-hole spray is adopted to realize the uniform, controllable temperature and speed addition of the multi-stage initiator in the reaction system, thereby effectively avoiding the implosion problem caused by the excessive amount of local initiator.

[0016] 3. The utility model adds a dispersion baffle in the reactor, which can change the flow pattern and turbulence degree of the reaction materials in the reactor, thereby increasing the mixing and stirring effect; by effectively breaking the flow of the fluid, it avoids the formation of dead zones or local uneven mixing in the reactor, which helps to ensure the uniform progress of the reaction.

[0017] 4. The utility model is provided with an intelligent sensor on the dispersion baffle, which can accurately sense the thickness of the attached matter on the baffle surface. Once the attached matter exceeds the sensor threshold, the system will sound an alarm to achieve regular maintenance and preventive maintenance, thereby increasing the service life of the equipment and giving full play to the stirring effect of the baffle during the reaction process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The utility model is a cross-sectional view of the reaction kettle provided by the utility model.

[0019] Figure 2 This is a schematic diagram of the structure of the initiator feeding tube.

[0020] In the figure, 1-mixing agitator, 2-mixing kettle, 3-stirring paddle, 4-raw material discharge valve, 5-injection pump, 6-initiator feeding pipe, 7-temperature sensor, 8-nitrogen inlet, 9-dispersion baffle, 10-cold / hot medium reflux pipeline, 11-discharge valve, 12-constant temperature heating / refrigeration device, 13-heating switch, 14-refrigeration switch, 15-temperature display, 16-constant temperature heating / refrigeration device switch, 17-sight glass, 18-cold / hot medium inlet, 19-cold / hot medium outlet, 20-reactor body, 21-intelligent sensor, 22-multi-hole spray head, 23-check valve. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] This embodiment provides a reaction kettle for preparing a viscoelastic polymer emulsion, comprising a mixing kettle 2, a reaction kettle body 20 and a constant temperature heating / cooling device 12. Figure 1 shown.

[0023] As an implementation method in this embodiment, the mixing kettle 2 is connected to the inner cavity of the reactor body 20 through a pipeline, and a mixing agitator 1 is arranged in the mixing kettle 2. The mixing agitator 1 has a high-speed dispersion shaft and is controlled by a high-speed stirring motor. The stirring paddle 3 arranged on the mixing agitator 1 is a frame-type stirring paddle. The mixing kettle 2 delivers the raw materials into the inner cavity of the reactor body 20 through the raw material discharge valve 4 and the injection pump 5.

[0024] As an implementation method in this embodiment, the reactor body 20 is of a sleeve type, and the sleeve is connected to the cold / hot medium inlet 18 and the cold / hot medium outlet 19 of the constant temperature heating / refrigeration device 12 through a pipeline. The circulating cold / hot medium can ensure the smooth progress of the reaction process, reduce the temperature increase caused by the self-acceleration of the reaction, avoid the occurrence of explosive polymerization or sticking to the kettle, and improve the quality of the emulsion product; the utility model controls the required temperature of the reaction system through the constant temperature heating / refrigeration device, which can effectively control the reaction temperature, ensure the smooth progress of the reaction process, reduce the temperature increase caused by the self-acceleration of the reaction, and avoid the occurrence of explosive polymerization, gelation or sticking to the kettle.

[0025] As an implementation method in this embodiment, the reactor body 20 is provided with an initiator feeding pipe 6 and a nitrogen inlet 8. The introduction of nitrogen can improve the deoxygenation efficiency, effectively eliminate the inhibitory effect of oxygen on free radical polymerization, and improve the initiation efficiency; a number of dispersion baffles 9 are evenly arranged inside the reactor body 20. The baffles can change the flow mode and turbulence degree inside the reactor, thereby increasing the heat transfer effect. By changing the flow path of the fluid, it can help improve the heat transfer efficiency between the reaction materials and the reaction medium, accelerate the reaction rate, and reduce the reaction time. At the same time, the setting of the baffle can adjust the flow direction and speed of the fluid, which can effectively prevent the occurrence of local uneven mixing in the reactor, avoid the formation of dead zones or local uneven mixing in the reactor, and help ensure the uniform progress of the reaction. An inductor 21 is arranged on the dispersion baffle 9, and a porous spray head 22 is evenly arranged on the initiator feeding pipe 6 extending into the reactor body 20. A check valve 23 is arranged at the inlet end of the porous spray head 22, such as Figure 2 As shown, a temperature sensor 7 is also provided in the reactor body 20 .

[0026] As an implementation method in this embodiment, a viewing mirror 17 is also provided on the reactor body 20, which is conducive to observing the internal conditions of the reactor at different time periods.

[0027] As an implementation method in this embodiment, the reactor body 20 discharges the material through a discharge valve 11 arranged at the tail.

[0028] As an implementation method in this embodiment, the constant temperature heating / cooling device 12 is provided with a heating switch 13, a cooling switch 14, a temperature display 15 and a constant temperature heating / cooling device switch 16.

[0029] Working principle and process of this utility model:

[0030] After the utility model is installed, the reaction raw materials are mixed evenly through the mixing kettle 2, and then the raw material discharge 4 is opened, and the raw materials are added to the reactor 20 through the injection pump 5, and N2 is passed through the nitrogen inlet 8. The temperature of the reaction system is observed through the temperature sensor 7 on the reactor body 20. When the temperature reaches the required temperature, the initiator is slowly and uniformly added from the initiator feeding pipe 6. The constant temperature heating / refrigeration device 12 is connected with the cold / hot medium inlet 18 and the cold / hot medium outlet 19 to control the reaction temperature. The reaction is continued for 2 to 4 hours. After stopping stirring, the nitrogen is stopped and the reaction is allowed to stand. During the reaction, the reaction phenomenon in the reactor can be observed through the sight glass 17 to observe the change of the reaction temperature. When the reaction temperature suddenly rises, the controller connected to the temperature sensor 7 will automatically turn off the constant temperature heating, turn on the refrigeration switch 14, and continue to observe the reaction temperature. When the reaction temperature is stable, turn off the refrigeration switch and continue to stand for reaction. When the reaction time is reached and the temperature in the kettle drops to room temperature, a phase inversion agent accounting for a certain proportion of the total mass of the emulsion is added to obtain a viscoelastic polymer emulsion. Stop stirring and discharge the material from the discharge port 11.

[0031] The emulsion reactor of the utility model is used for preparing viscoelastic polymer emulsion, especially nano viscoelastic polymer emulsion thickener for fracturing fluid. A high-speed stirring motor and a connected high-speed dispersion shaft are provided. In the early stage of emulsion synthesis, the raw materials can be mixed and emulsified in the mixing kettle, and then the multi-stage initiation system can be controllably added in the reactor. In particular, the initiator feeding device of the utility model is provided with a multi-hole spray injection structure. According to the difference in the decomposition temperature and half-life of the initiation system, the polymer synthesis can adopt a multi-stage initiation method to ensure that the monomer polymerization is thorough and the monomer residue is low, thereby optimizing the polymerization process and improving the polymerization technology.

[0032] The reactor has the characteristics of good stirring and mixing effect, uniform material reaction, easy control of reaction temperature, etc.

[0033] In the above description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed above.

[0034] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A reaction kettle for preparing a viscoelastic polymer emulsion, characterized in that: The invention comprises a mixing kettle (2), a reaction kettle body (20) and a constant temperature heating / refrigeration device (12); the reaction kettle body (20) is of a sleeve type, the sleeve is connected to a cold / hot medium inlet (18) and a cold / hot medium outlet (19) of the constant temperature heating / refrigeration device (12) through a pipeline, and the mixing kettle (2) is connected to the inner cavity of the reaction kettle body (20) through a pipeline; The reactor body (20) is provided with an initiator feeding pipe (6) and a nitrogen inlet (8), and a plurality of dispersion baffles (9) are evenly arranged inside. The dispersion baffles (9) are provided with sensors (21). The initiator feeding pipe (6) extending into the reactor body (20) is evenly provided with multi-porous spray heads (22), and a check valve (23) is provided at the inlet end of the multi-porous spray head (22). A temperature sensor (7) is also provided inside the reactor body (20).

2. The reaction kettle for preparing a viscoelastic polymer emulsion according to claim 1, characterized in that: The reactor body (20) is also provided with a sight glass (17).

3. A reaction kettle for preparing a viscoelastic polymer emulsion according to claim 1 or 2, characterized in that: The mixing kettle (2) is provided with a mixing stirrer (1), and the stirring paddle (3) provided on the mixing stirrer (1) is a frame-type stirring paddle.

4. The reaction kettle for preparing a viscoelastic polymer emulsion according to claim 3, characterized in that: A raw material discharge valve (4) and a material injection pump (5) are provided on the pipeline connecting the mixing kettle (2) and the reaction kettle body (20).

5. The reaction kettle for preparing a viscoelastic polymer emulsion according to claim 4, characterized in that: A discharge valve (11) is also provided at the tail of the reactor body (20).

6. The reaction kettle for preparing a viscoelastic polymer emulsion according to claim 5, characterized in that: The constant temperature heating / refrigeration device (12) is provided with a heating switch (13), a cooling switch (14), a temperature display (15) and a constant temperature heating / refrigeration device switch (16).

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