A polycarboxylate water-reducing agent cyclic polymerization reaction device and method

Abstract

The invention provides a polycarboxylate water-reducing agent circulating polymerization reaction device and method, including a tank body and a pipeline pump, wherein the tank body is provided with a feed port and a discharge port, wherein the discharge port is connected to the pipeline pump through a pipeline, wherein a feeding port is provided on the pipeline, wherein the feed port is connected to the pipeline pump through a main circulation pipeline, wherein the main circulation pipeline is connected to the feeding port through a sampling circulation pipeline. The polycarboxylate water-reducing agent circulating polymerization reaction device of the invention does not adopt a vertical paddle stirring homogenization mode, so there is no need to consider the impact of the liquid centrifugal force on the tank body, the requirements for the tank body material are reduced, and a plastic storage tank can be used to replace a traditional enamel or metal reactor, which greatly reduces the cost, installation cost and use and maintenance costs.

Description

Technical Field

[0001] The invention belongs to the field of water reducers, and in particular relates to a polycarboxylic acid water reducer cyclic polymerization reaction device and method. Background Art

[0002] Water reducer refers to an admixture that can reduce the amount of mixing water and improve the strength of concrete under the condition that the workability of concrete and the amount of cement remain unchanged; or save the amount of cement under the condition that the workability and strength remain unchanged. As a new product in this field, polycarboxylate water reducer has gradually replaced traditional products such as aliphatic and naphthalene series due to its many advantages such as large adjustable space of molecular structure, multiple controllable parameters of manufacturing technology, and green and environmentally friendly production process.

[0003] The polycarboxylic acid reaction modes in the prior art all achieve homogeneity of the materials in the polymerization process by driving the reducer output to the stirring paddle through a motor. When the density difference between the phases in the system is large, this homogenization method easily causes a concentration difference in the vertical direction inside the liquid, thereby affecting the overall reaction sufficiency of the polycarboxylic acid water-reducing agent and failing to accurately meet the requirements of the designed molecular structure.

[0004] Currently, the polycarboxylic acid synthesis industry generally uses acrylic acid as a polymerization monomer, which is a hazardous chemical, flammable and explosive, and has high requirements for storage and transportation. At the same time, due to its strong volatility and irritation, it has a great impact on personnel and the environment during the polymerization reaction. Summary of the invention

[0005] In view of this, the present invention aims to overcome the defects in the prior art and proposes a polycarboxylic acid water-reducing agent cyclic polymerization reaction device and method.

[0006] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0007] A polycarboxylate water-reducing agent circulating polymerization reaction device comprises a tank body and a pipeline pump. The tank body is provided with a feed port and a discharge port, the discharge port is connected to the pipeline pump through a pipeline, the pipeline is provided with a feeding port, the feed port is connected to the pipeline pump through a main circulation pipeline, and the main circulation pipeline is connected to the feeding port through a sampling circulation pipeline.

[0008] Furthermore, the discharge port is provided with a discharge pipe.

[0009] Furthermore, a feeding funnel is arranged inside the feed port, the feeding funnel is connected to the main circulation pipeline, the lower end of the feeding funnel is a conical structure, and a plurality of feeding holes are arranged at the bottom.

[0010] Furthermore, a plurality of node homogenizers are evenly arranged on the main circulation pipeline, a plurality of channels are arranged in the node homogenizers, and the channels are connected with the main circulation pipeline; the node homogenizers are cylindrical in structure, and the outer diameter of the node homogenizers is smaller than the outer diameter of the main circulation pipeline.

[0011] A polycarboxylate water reducer, the water reducer is made of raw materials including the following mass percentages:

[0012]

[0013]

[0014] The regulator is at least one of diphenylmethane diisocyanate or toluene diisocyanate. The regulator can generate a large amount of carbon dioxide gas when in contact with water, and the generated gas can form an "air flow stirring" effect as the entire reaction material circulates, effectively accelerating the homogenization speed of various components in the liquid.

[0015] The chemical formula for the reaction between isocyanates and water is as follows:

[0016] 2RNCO+H2O→RNHCONHR+CO2↑

[0017] Furthermore, the monomer A is at least one of isopentenyl polyethylene glycol ether, isobutylene polyethylene glycol ether, allyl polyoxyethylene ether or methoxy polyethylene glycol monomethyl ether; and the monomer B is at least one of potassium acrylate, sodium acrylate or magnesium acrylate.

[0018] Furthermore, the oxidant is at least one of hydrogen peroxide, ammonium persulfate or potassium persulfate; the reducing agent is at least one of ferrous sulfate, sodium sulfite or vitamin C; and the chain transfer agent is at least one of mercaptoethanol, mercaptopropionic acid or sodium hypophosphite.

[0019] A method for using the polycarboxylate water-reducing agent circulating polymerization reaction device comprises the following steps:

[0020] (1) injecting the kettle bottom water, monomer A and regulator through the feed port, and then starting the pipeline pump for circulation;

[0021] (2) After the materials in step (1) are mixed uniformly, the oxidant is added through the feed port;

[0022] (3) After the materials in step (2) are fully mixed, the dropwise liquid is uniformly injected through the feed port and circulated for 60-180 min. The liquid flow rate in the main circulation pipeline is 60-80 m / h. After the reaction is completed, the polycarboxylate water reducer is obtained.

[0023] Furthermore, the dropwise addition liquid in step (3) is a mixture of the monomer B, the reducing agent, the chain transfer agent and the dilution water.

[0024] Furthermore, the dropping liquid in step (3) is injected into the dropping liquid at a uniform speed in a gravity flow manner; the gravity flow manner is: a liquid level difference is generated between the dropping liquid and the feeding port, so that the dropping liquid is injected into the feeding port at a uniform speed according to gravity.

[0025] Since the polycarboxylic acid polymerization reaction environment is a multiphase material mixed state, the traditional vertical paddle stirring can quickly homogenize the materials on the same horizontal plane, but the subsequent added materials need a certain amount of time to achieve vertical homogenization, that is, there is a concentration difference from the liquid surface to the bottom of the tank. This will lead to regional differences in the system polymerization reaction, which is not conducive to the consistency of the molecular structure of the final product. The polycarboxylic acid water-reducing agent cyclic polymerization reaction method described in the present invention is cyclic homogenization, and the liquid is pumped out from the bottom of the tank body by a high-power pipeline pump, and dispersed and refluxed to the top of the tank body, and a regulator that can achieve the "airflow stirring" effect is added, which can quickly achieve material homogenization, so that the molecular weight distribution of the polymerization product is uniform and the performance is better.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] The polycarboxylate water-reducing agent circulating polymerization reaction device created by the present invention does not adopt a vertical paddle stirring homogenization mode, so there is no need to consider the impact of liquid centrifugal force on the tank body, the requirements for the tank body material are reduced, and plastic storage tanks can be used to replace traditional enamel or metal reactors, which greatly reduces the cost, installation cost and use and maintenance costs.

[0028] The polycarboxylic acid water-reducing agent circulating polymerization reaction device created by the present invention eliminates the reducer and the stirring paddle (blade), adopts a pipeline circulation method to homogenize the material, simplifies the equipment, and greatly reduces the cost, installation cost and maintenance cost; the circulating polymerization reaction mode has a high homogenization efficiency. According to tests, compared with the traditional vertical paddle stirring, the process time can be shortened by about 40%, which greatly improves the production efficiency.

[0029] The polycarboxylate water-reducing agent created by the present invention adopts acrylates as substitutes for acrylic acid, and simultaneously adds a regulator to improve the reaction activity of the monomer, thereby effectively solving the above-mentioned safety, environmental and occupational health hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0031] Figure 1A schematic diagram of a polycarboxylate water-reducing agent circulating polymerization reaction device according to an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of a feeding funnel according to an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of a node homogenizer according to an embodiment of the present invention;

[0034] Figure 4 A cross-sectional view of a node homogenizer according to an embodiment of the present invention;

[0035] Figure 5 A cross-sectional view of the reaction device described in the comparative example of the present invention.

[0036] Description of reference numerals:

[0037] 1. Tank body; 2. Pipeline pump; 3. Feeding port; 4. Sampling circulation pipeline; 5. Main circulation pipeline; 6. Discharge pipeline; 7. Feeding funnel; 8. Feeding hole; 9. Node homogenizer; 10. Channel; 11. Stirring paddle; 12. Raw material feed pipeline; 13. Product discharge pipeline. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0040] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0041] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0042] Example 1

[0043] like Figure 1-4 As shown, a polycarboxylate water-reducing agent circulating polymerization reaction device includes a tank body and a pipeline pump. The tank body is provided with a feed port and a discharge port. The discharge port is connected to the pipeline pump through a pipeline. The pipeline is provided with a feeding port. The feed port is connected to the pipeline pump through a main circulation pipeline. The main circulation pipeline is connected to the feeding port through a sampling circulation pipeline. The discharge port is provided with a discharge pipeline. Multiple valves are arranged at various locations of the pipeline to control the flow direction of the material.

[0044] A feeding funnel is arranged inside the feed port, and the feeding funnel is connected to the main circulation pipeline. The lower end of the feeding funnel is a conical structure, and a plurality of feeding holes with a diameter of 1.0 cm are arranged at the bottom. When the liquid flows through, it will be dispersed and fall into the tank body, which is more conducive to liquid homogenization.

[0045] A node homogenizer is installed every 0.5m on the main circulation pipeline, and a plurality of channels with a diameter of 1.0cm are arranged in the node homogenizer, and the channels are connected to the main circulation pipeline; the node homogenizer is a cylindrical structure, and the outer diameter of the node homogenizer is smaller than the outer diameter of the main circulation pipeline. When the liquid flows through the node homogenizer, it will be diverted by the channel to form multiple branches and then converge again, so as to accelerate the homogenization speed of each component in the liquid.

[0046] The tank body, node homogenizer and feeding funnel can all be made of plastic materials that do not react with the water reducing agent components.

[0047] A polycarboxylic acid water reducer is prepared from the following raw materials in percentage by mass: 2000 kg of kettle bottom water, 2000 kg of isobutylene polyethylene glycol ether, 55 kg of diphenylmethane diisocyanate, 50 kg of hydrogen peroxide, 250 kg of potassium acrylate, 5 kg of sodium sulfite, 10 kg of mercaptopropionic acid and 700 kg of dilution water.

[0048] A method for using the polycarboxylate water-reducing agent circulating polymerization reaction device comprises the following steps:

[0049] (1) injecting the kettle bottom water, monomer A and regulator through the feed port, and then starting the pipeline pump for circulation;

[0050] (2) After the materials in step (1) are mixed for 10 minutes, the oxidant is added through the feed port;

[0051] (3) After the materials in step (2) are fully mixed, the dropwise liquid is uniformly injected through the feed port in a gravity flow manner and circulated for 180 minutes. The liquid flow rate in the main circulation pipeline is 70 m / h. After the reaction is completed, the polycarboxylate water reducer is obtained.

[0052] The droplet in step (3) is a mixture of the monomer B, reducing agent, chain transfer agent and dilution water. The gravity flow method is to generate a liquid level difference between the droplet and the feed port, so that the droplet is injected into the feed port at a uniform speed according to gravity.

[0053] Example 2

[0054] The difference from Example 1 is that:

[0055] A polycarboxylic acid water reducer is prepared from the following raw materials in percentage by mass: 2000 kg of kettle bottom water, 2000 kg of isobutylene polyethylene glycol ether, 55 kg of toluene diisocyanate, 50 kg of hydrogen peroxide, 250 kg of potassium acrylate, 5 kg of sodium sulfite, 10 kg of mercaptopropionic acid and 700 kg of dilution water.

[0056] Comparative Example 1

[0057] A traditional polycarboxylate water reducer is prepared from raw materials including the following mass percentages: 2000 kg of kettle bottom water, 2000 kg of isobutylene polyglycol ether, 50 kg of hydrogen peroxide, 200 kg of acrylic acid, 5 kg of sodium sulfite, 10 kg of mercaptopropionic acid, and 700 kg of dilution water.

[0058] A method for using the conventional polycarboxylate water-reducing agent polymerization reaction device comprises the following steps:

[0059] (1) injecting the kettle bottom water and monomer A through the raw material feeding pipeline, and turning on the stirring motor for homogenization;

[0060] (2) After the materials in step (1) are mixed for 10 minutes, the oxidant is added through the raw material feed pipeline;

[0061] (3) After the materials in step (2) are fully mixed, the dropwise addition liquid is uniformly injected through the raw material feed pipeline in a manner of setting a fixed flow rate (5 kg / min). This process lasts for 180 min, and the stirring speed is 60 r / min.

[0062] (4) After step (3) is completed, the stirring speed is controlled to remain unchanged and maintained for 120 minutes. After the reaction is completed, the polycarboxylate water-reducing agent is obtained.

[0063] The droplet in step (3) is a mixture of the monomer B, the reducing agent, the chain transfer agent and the dilution water. The fixed flow injection method is: the droplet is injected through a liquid peristaltic pump with a controllable speed, so that the droplet is injected into the feed port at a set flow rate (5kg / min).

[0064] like Figure 5 As shown, a polymerization reaction device using the conventional polycarboxylate water-reducing agent comprises a tank body, a stirring paddle is arranged in the tank body, and a raw material feeding pipe and a product discharging pipe are arranged on the tank body.

[0065] According to the national standard GB 8076-2008 "Concrete Admixtures" of this product, the performances of the products obtained in Examples 1-2 and Comparative Example 1 were compared, and the results are shown in Table 1.

[0066] Table 1

[0067]

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for using a polycarboxylate water-reducing agent circulating polymerization reaction device, characterized in that: The polycarboxylate water-reducing agent circulating polymerization reaction device comprises a tank body and a pipeline pump. The tank body is provided with a feed port and a discharge port. The discharge port is connected to the pipeline pump through a pipeline. The pipeline is provided with a feeding port. The feed port is connected to the pipeline pump through a main circulation pipeline. The main circulation pipeline is connected to the feeding port through a sampling circulation pipeline. A feeding funnel is arranged on the inner side of the feed port. The feeding funnel is connected to the main circulation pipeline. The lower end of the feeding funnel is a conical structure, and a plurality of feeding holes are arranged at the bottom. A plurality of node homogenizers are evenly arranged on the main circulation pipeline. A plurality of channels are arranged in the node homogenizer, and the channels are connected to the main circulation pipeline. The node homogenizer is a cylindrical structure, and the outer diameter of the node homogenizer is smaller than the outer diameter of the main circulation pipeline. The water reducing agent is made of raw materials including the following mass percentages: 40-50% water in the kettle, Monomer A 30-40%, Regulator 1.0-2.0%, Oxidant 0.5-1.0%, Monomer B 4.0-5.0%, Reducing agent 0.1-0.2%, Chain transfer agent 0.2-0.3%, Dilution water 13-15%; The regulator is at least one of diphenylmethane diisocyanate or toluene diisocyanate; The method of using a polycarboxylate water-reducing agent circulating polymerization reaction device comprises the following steps: (1) injecting kettle bottom water, monomer A and regulator through the feed port, and then starting the pipeline pump for circulation; (2) After the materials in step (1) are mixed uniformly, an oxidant is added through the feed port; (3) After the materials in step (2) are fully mixed, the droplet is uniformly injected through the feed port and circulated for 60-180 min. The liquid flow rate in the main circulation pipeline is 60-80 m / h. After the reaction is completed, the polycarboxylate water reducer is obtained; The dropwise addition liquid in step (3) is a mixture of the monomer B, the reducing agent, the chain transfer agent and the dilution water.

2. The method according to claim 1, characterized in that: The discharge port is provided with a discharge pipe.

3. The method according to claim 1, characterized in that: The monomer A is at least one of isopentenyl polyethylene glycol ether, isobutylene polyethylene glycol ether, allyl polyoxyethylene ether or methoxy polyethylene glycol monomethyl ether; the monomer B is at least one of potassium acrylate, sodium acrylate or magnesium acrylate.

4. The method according to claim 1, characterized in that: The oxidant is at least one of hydrogen peroxide, ammonium persulfate or potassium persulfate; the reducing agent is at least one of ferrous sulfate, sodium sulfite or vitamin C; and the chain transfer agent is at least one of mercaptoethanol, mercaptopropionic acid or sodium hypophosphite.

5. The method according to claim 1, characterized in that: The dripping liquid in step (3) is injected at a uniform speed by gravity; the gravity flow method is: a liquid level difference is generated between the dripping liquid and the feeding port, so that the dripping liquid is injected into the feeding port at a uniform speed according to gravity.

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