A reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer

Abstract

This utility model discloses a reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizers, relating to the technical field of polycarboxylate superplasticizer production equipment. It includes a stirring rod with multiple arranged stirring blades. The stirring rod is hollow inside, and a feed pipe is movably connected to the bottom of the stirring rod. Multiple arranged spray pipes are also provided on the stirring rod, located beside the stirring blades. This utility model positions the spray pipes beside the stirring blades, enabling the spraying of ice water into the reaction zone surrounding the stirring blades, reducing the local temperature and preventing rapid polymerization caused by high temperatures. It also appropriately dilutes the concentration of the unsaturated acid / ester—acrylic acid—in the localized area, solving the problem of explosive polymerization and gelation caused by excessively high concentrations.

Description

Technical Field

[0001] This utility model relates to the technical field of polycarboxylate superplasticizer production equipment, and in particular to a reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer. Background Technology

[0002] Currently, most polycarboxylate superplasticizers are synthesized and produced using room-temperature polymerization. The raw materials typically include polyether macromonomers, unsaturated acids / esters, initiators, reducing agents, and chain transfer agents. Under the action of the initiator, the raw materials continuously polymerize and grow chains, ultimately forming a comb-shaped molecular structure in the polycarboxylate superplasticizer. The polymerization reaction is carried out in an aqueous solution. Water serves two main purposes as the reaction medium: firstly, its dispersion effect reduces the probability of collisions with active free radicals, thus slowing down the polymerization reaction and extending the reaction time to meet the designed carboxylic acid molecular structure requirements; secondly, it acts as a temperature buffer, slowing down the rate of temperature rise in the polymerization reaction and preventing excessively rapid temperature increases that could lead to chain reactions and explosive polymerization, thereby reducing the performance of the polycarboxylate superplasticizer product. Therefore, polycarboxylate superplasticizers are produced using room-temperature polymerization. Due to the addition of water and the need to balance production time, equipment, and product performance, the final product concentration is limited; typically, the final concentration of the polycarboxylate superplasticizer mother liquor semi-finished product is 40-50%. In order to save on the cost of long-distance transportation and compounding, manufacturers have tried to polymerize and synthesize high-concentration polycarboxylate superplasticizer mother liquor semi-finished products. Due to the excessively high polymerization reaction concentration, the monomers are prone to local burst polymerization due to equipment limitations, especially concentrated near the liquid surface of the reactor, the stirring rod wall and the stirring blades, which ultimately leads to a decline in the performance of polycarboxylate superplasticizer.

[0003] The reason for the localized burst polymerization of monomers: As the unsaturated acid / ester is added dropwise into the reactor, the vortex created by stirring causes the acrylic acid and other substances that have not yet dispersed to accumulate at the stirring rod on the surface of the liquid, resulting in localized aggregation. As the concentration and temperature rise, the more polymerizable acrylic acid self-polymerizes to form a gel, which adheres to the wall of the stirring rod on the liquid surface. As the stirring rod rotates, a negative pressure is created at the inclined surface (back side) of the stirring paddle. The added unsaturated acid / ester—acrylic acid—is easily drawn to this location by the vortex, and with increasing concentration and temperature, it bursts into a gel. Utility Model Content

[0004] To overcome at least one of the defects described in the prior art, this invention provides a reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizers. This addresses the problem of localized explosive polymerization of polycarboxylate superplasticizers.

[0005] The technical solution adopted by this utility model to solve its problem is:

[0006] A reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer includes a stirring rod with multiple arranged stirring blades. The stirring rod is hollow inside, and a feed pipe is movably connected to the bottom of the stirring rod. Multiple arranged spray pipes are also provided on the stirring rod, with the spray pipes located next to the stirring blades.

[0007] With the above solution, the spray nozzle assembly is located next to the stirring blade assembly, which can spray ice water onto the reaction zone that gathers next to the stirring blade assembly, reduce the local temperature, avoid the rapid polymerization reaction caused by high temperature, and also appropriately dilute the local concentration of unsaturated acid / ester - acrylic acid, thus solving the problem of excessively high concentration causing rapid reaction and explosive gelation.

[0008] Furthermore, the plurality of stirring blade groups are arranged in a staggered 90-degree pattern from top to bottom, and the plurality of spray pipe groups are the same number as the stirring blade groups and are arranged in the same way as the stirring blade groups. The plurality of spray pipe groups are located on the upper side of the stirring blade groups and are parallel to the stirring blade groups.

[0009] Through the above-mentioned further solutions, the staggered 90-degree arrangement of the stirring blades can effectively make the materials more fully mixed in the reactor, prevent local material accumulation or retention, and thus avoid the risk of explosive polymerization caused by high local concentration.

[0010] Furthermore, the spray pipe assembly includes two spray horizontal pipes, one end of which is open and the other end is closed. The spray horizontal pipe with the open end is fixedly installed on the stirring rod and is connected to the inside of the stirring rod. The spray horizontal pipe is provided with a spray nozzle, and a one-way valve is provided inside the spray nozzle.

[0011] Furthermore, the stirring blade assembly includes two stirring blades, which are symmetrically arranged. Each stirring blade includes a fixing member and stirring blades. The fixing members of both stirring blades are provided with slots, and the two fixing members are fixedly installed on the stirring rod by bolts passing through the slots.

[0012] Furthermore, the stirring blades are positioned at a 45-degree angle on the fixed component, with the stirring blades facing downwards on the side facing the direction of rotation.

[0013] Through the above-mentioned further solutions, the 45-degree stirring blades not only help to generate greater thrust, but also avoid greater resistance, reducing energy consumption and equipment wear.

[0014] Furthermore, the fixing member has an opening on the upper side of the stirring blade, and the spray pipe is located in the opening, so that the spray pipe is located above the side opposite to the side of the stirring blade in the direction of rotation.

[0015] The above-mentioned further solutions ensure that the ice water sprayed from the horizontal nozzle can be quickly carried into the mixing area, avoiding the occurrence of excessively high local concentrations and temperatures. The position of the stirring blades is limited by the openings, preventing the stirring blades from being installed too far from the horizontal nozzle and also preventing the stirring blades from shifting.

[0016] Furthermore, the injection nozzle faces the back side in the direction of rotation of the stirring blade.

[0017] The above-mentioned further method allows for the rapid addition of sprayed ice water to the aggregated acrylic acid, lowering the temperature and diluting it to prevent localized explosive gelation.

[0018] Furthermore, the stirring rod is provided with multiple vertically arranged injection holes at the liquid surface. Each injection hole is equipped with a one-way valve. The injection hole at the highest position is above the liquid surface, and the injection hole at the lowest position is below the liquid surface.

[0019] The above-mentioned further solution allows for the direct spraying of ice water onto the stirring rod that accumulates on the liquid surface, preventing explosive gelation at the stirring rod located on the liquid surface.

[0020] Furthermore, it also includes a tank body, on which a braking mechanism is fixedly installed. The output end of the braking mechanism passes through the tank body to the interior and is connected to the stirring rod. A support frame is provided inside the tank body. One end of the support frame is fixedly installed on the inner side wall of the tank body, and the other end is fixedly installed with a clamp. The clamp is connected to the stirring rod through a bearing.

[0021] Through the above-mentioned further solution, the clamp is connected to the stirring rod through a bearing to prevent it from wobbling when rotating at high speed, ensuring that it remains stable and does not shake during long-term operation.

[0022] Furthermore, the support frame is provided with a bracket, and the bracket is provided with a fixing ring for fixing the feed pipe. The feed pipe and the stirring rod are connected end to end and pass through the tank to the outside.

[0023] The above-mentioned further measures ensure the stability of the feed pipe, prevent the feed pipe from shaking during operation, and avoid affecting the sealing at the connection with the stirring rod.

[0024] In summary, the reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer provided by this utility model has the following technical effects:

[0025] Ice water is sprayed from the inclined surface of the stirring blades through the spray pipe assembly. The ice water can reduce the local temperature and avoid the rapid polymerization reaction caused by high temperature. It can also appropriately dilute the local concentration of unsaturated acid / ester - acrylic acid, and solve the problem of explosive gelation caused by excessively high concentration and rapid reaction. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0027] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0028] Figure 2 This is a schematic diagram of the internal structure of the tank of this utility model;

[0029] Figure 3 For the present utility model Figure 2 A magnified schematic diagram of the structure at point A in the middle.

[0030] In the diagram: 1. Stirring rod; 11. Feed pipe; 12. Injection hole; 2. Spraying horizontal pipe; 21. Injection nozzle; 3. Stirring paddle; 31. Fixing component; 311. Groove; 312. Opening; 32. Stirring blade; 4. Tank body; 41. Braking mechanism; 42. Support frame; 421. Clamp; 422. Bracket; 423. Fixing ring. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0032] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0034] Example:

[0035] refer to Figure 2 and Figure 3 As shown, a reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer includes a tank 4. A braking mechanism 41 is fixedly installed on the tank 4. The braking mechanism 41 is a motor. The output end of the braking mechanism 41 passes through the tank 4 and connects to the stirring rod 1 inside. A support frame 42 is provided inside the tank 4. One end of the support frame 42 is fixedly installed on the inner side wall of the tank 4, and the other end is fixedly installed with a clamp 421. The clamp 421 is connected to the stirring rod 1 through a bearing. One end of the stirring rod 1 is fixedly connected to the output end of the braking mechanism 41, and the other end is fixed in the clamp 421 through a bearing. This can prevent the stirring rod 1 from wobbling when rotating at high speed and ensure that it remains stable and does not shake during long-term operation.

[0036] refer to Figure 2 and Figure 3 As shown, the stirring rod 1 is fixed inside the clamp 421 and one end is rotatably connected to the feed pipe 11. The feed pipe 11 and the stirring rod 1 are connected end to end and pass through the tank 4 to the outside. The support frame 42 is provided with a bracket 422. The bracket 422 is provided with a fixing ring 423 for fixing the feed pipe 11. The fixing ring 423 ensures the stability of the feed pipe 11, prevents the feed pipe 11 from shaking during operation, and avoids affecting the sealing of the connection with the stirring rod 1.

[0037] It should be noted that the feed pipe 11 is rotatably connected to the stirring rod 1, and the connection can be achieved through a rotary joint. The connection method between them is existing technology and will not be described in detail. The feed pipe 11 can pass through the tank 4 by direct welding, such as the feed pipe 11 being made of metal and directly welded to the tank 4, or a channel can be set on the tank 4, through which the feed pipe 11 passes to the outside and is sealed.

[0038] In a further explanation of this embodiment, the feed pipe 11 passes through the tank 4 and is connected to an external conveying pump, which can deliver chilled water into the feed pipe 11.

[0039] refer to Figure 1 and Figure 2 As shown, the stirring rod 1 is hollow inside and connected to the feed pipe 11, allowing ice water to enter the stirring rod 1. The stirring rod 1 is equipped with multiple arranged spray pipe groups, each including two spray horizontal pipes 2. One end of the spray horizontal pipe 2 is open and the other end is closed. The spray horizontal pipe 2 is fixedly installed on the stirring rod 1 with the open end and is connected to the inside of the stirring rod 1. The spray horizontal pipe 2 is equipped with a spray nozzle 21, and a one-way valve is installed inside the spray nozzle 21, through which ice water can be sprayed to the outside.

[0040] refer to Figure 1 and Figure 2 As shown, the stirring rod 1 has multiple vertically arranged spray holes 12 located at the liquid surface. Each spray hole 12 is equipped with a one-way valve. The highest spray hole 12 is above the liquid surface, and the lowest spray hole 12 is below the liquid surface. This allows for the direct spraying of ice water onto the stirring rod 1 that accumulates on the liquid surface, preventing explosive gel formation at the stirring rod 1 located on the liquid surface.

[0041] Among them, the one-way valve has a backflow prevention function. Under pressure, cooling water can be sprayed into the tank 4, while preventing the material in the tank 4 from entering the stirring rod 1 or the spray pipe 2 through the one-way valve.

[0042] refer to Figure 1 and Figure 2 As shown, the stirring rod 1 is equipped with multiple sets of stirring blades arranged in a staggered 90-degree pattern from top to bottom. The number of multiple spray pipe sets is the same as that of the stirring blade sets, and they are arranged in the same way. The multiple spray pipe sets are located on the upper side of the stirring blade sets and are parallel to the stirring blade sets. The staggered 90-degree arrangement of the stirring blade sets can effectively make the materials more fully mixed in the reactor, prevent local material accumulation or retention, and thus avoid the risk of explosive agglomeration caused by high local concentration.

[0043] refer to Figure 1 and Figure 2 As shown, the stirring blade assembly includes two stirring paddles 3, which are symmetrically arranged. Each stirring paddle 3 includes a fixing member 31 and stirring blades 32. The stirring blades 32 are arranged at a 45-degree angle on the fixing member 31. The side of the stirring blades 32 facing down (slanted down) in the direction of rotation is the front, and the opposite side facing up (slanted up) is the back. The fixing members 31 of both stirring paddles 3 are provided with holes and slots 311, and the two fixing members 31 are fixedly installed on the stirring rod 1 by bolts passing through the holes and slots 311.

[0044] The fixing member 31 has an opening 312 on the upper side of the stirring blade 32. The spray pipe 2 is located in the opening 312, so that the spray pipe 2 is located above the back of the stirring blade 32. This ensures that the ice water sprayed by the spray pipe 2 can be quickly carried into the mixing area, avoiding the occurrence of excessive local concentration and temperature. The opening 312 limits the position of the stirring blade 32, preventing the stirring blade 32 from being too far away from the spray pipe 2 during installation, and also preventing the stirring blade 32 from shifting.

[0045] The spray pipe 2 is located on the back of the stirring blade 32, which is set at a 90-degree angle. This prevents the spray pipe 2 from colliding with a large amount of liquid, thus providing protection. At the same time, it can effectively spray ice water into the negative pressure area formed by the stirring blade 32 after stirring, thereby reducing the local temperature and preventing the rapid polymerization reaction caused by high temperature. It can also appropriately dilute the local concentration of unsaturated acid / ester - acrylic acid, thus solving the problem of excessively high concentration causing rapid reaction and explosive gelation.

[0046] The two horizontal spray pipes 2 correspond to the two stirring blades 32 respectively, ensuring that explosive gelation is prevented next to each stirring blade 32.

[0047] Among them, the 45-degree stirring blade 32 not only helps to generate greater thrust, but also avoids greater resistance, reducing energy consumption and equipment wear.

[0048] The spray nozzle 21 on the horizontal spray pipe 2 faces the back of the direction of rotation of the stirring blade 32, which can quickly add the sprayed ice water to the place where the acrylic acid is agitated by the stirring blade 32 to form a negative pressure, thereby reducing the temperature and diluting it, and preventing local bursting of gel.

[0049] The working principle of this utility model is as follows:

[0050] After the polycarboxylate superplasticizer synthesis reaction is completed and the heat preservation is finished, water needs to be added to reach the preset target solid content (40% or 50%, etc.). A portion of this water can be taken out and pretreated by adding ice to cool it down. During the stage of rapid temperature rise in the polymerization reaction, the cooled ice water is delivered from the feed pipe 11 to the stirring rod 1 through the delivery pump. It is sprayed out from the spray hole 12 on the surface of the stirring rod 1 and the spray nozzle 21 on the back of the spray pipe 2 of the stirring blade 32. The ice water can reduce the local temperature and avoid the rapid polymerization reaction caused by high temperature. At the same time, the water can appropriately dilute the local concentration of unsaturated acid / ester - acrylic acid, and solve the problem of excessively high concentration causing rapid reaction and explosive gelation.

[0051] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer, comprising a stirring rod (1), wherein the stirring rod (1) is provided with a plurality of arranged stirring blades, characterized in that: The stirring rod (1) is hollow inside, and the bottom of the stirring rod (1) is movably connected to the feed pipe (11). The stirring rod (1) is provided with multiple sets of spray pipes arranged in a row, and the spray pipe sets are located next to the stirring blades.

2. The reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 1, characterized in that: The multiple stirring blade groups are arranged in a staggered 90-degree pattern from top to bottom. The multiple spray pipe groups are the same number as the stirring blade groups and are arranged in the same way. The multiple spray pipe groups are located on the upper side of the stirring blade groups and are parallel to the stirring blade groups.

3. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 1, characterized in that: The spray pipe assembly includes two spray pipes (2), one end of which is open and the other end is closed. The spray pipe (2) has an open end that is fixedly installed on the stirring rod (1) and is connected to the inside of the stirring rod (1). The spray pipe (2) has a spray nozzle (21) and a one-way valve inside the spray nozzle (21).

4. The reaction device for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 3, characterized in that: The stirring blade assembly includes two stirring blades (3), which are symmetrically arranged. Each stirring blade (3) includes a fixing member (31) and stirring blades (32). The fixing members (31) of the two stirring blades (3) are provided with slots (311), and the two fixing members (31) are fixedly installed on the stirring rod (1) by bolts passing through the slots (311).

5. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 4, characterized in that: The stirring blade (32) is set at a 45-degree angle on the fixing member (31), and the stirring blade (32) is located on the side facing downward in the direction of rotation.

6. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 4, characterized in that: The fixing member (31) has an opening (312) on the upper side of the stirring blade (32), and the spraying horizontal pipe (2) is located in the opening (312), so that the spraying horizontal pipe (2) is located above the side opposite to the rotation direction of the stirring blade (32).

7. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 4, characterized in that: The injection port (21) faces the back of the direction of rotation of the stirring blade (32).

8. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 1, characterized in that: The stirring rod (1) has multiple vertically arranged spray holes (12) at the liquid surface. Each spray hole (12) is equipped with a one-way valve. The highest spray hole (12) is above the liquid surface, and the lowest spray hole (12) is below the liquid surface.

9. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 1, characterized in that: It also includes a tank (4), on which a braking mechanism (41) is fixedly installed. The output end of the braking mechanism (41) passes through the tank (4) to the inside and is connected to the stirring rod (1). A support frame (42) is provided inside the tank (4). One end of the support frame (42) is fixedly installed on the inner side wall of the tank (4), and the other end is fixedly installed with a clamp (421). The clamp (421) is connected to the stirring rod (1) through a bearing.

10. The reaction apparatus for preventing localized explosive polymerization of polycarboxylate superplasticizer according to claim 9, characterized in that: The support frame (42) is provided with a bracket (422), and the bracket (422) is provided with a fixing ring (423) for fixing the feed pipe (11). The feed pipe (11) and the stirring rod (1) are connected end to end through the tank (4) to the outside.

Images