A multifunctional antistatic agent feeding device capable of continuous injection and accurate metering

Abstract

This utility model relates to a multifunctional antistatic agent feeding device capable of continuous injection and precise metering, comprising: an antistatic agent dilution tank for receiving and mixing a high-viscosity first antistatic agent and a diluent to form a first antistatic agent diluted solution; a nitrogen generator connected to the antistatic agent dilution tank for bubbling and deoxygenating the first antistatic agent diluted solution; an antistatic agent feeding tank connected to the antistatic agent dilution tank for receiving the deoxygenated first antistatic agent diluted solution or directly receiving a second antistatic agent; a stirrer disposed within the antistatic agent feeding tank for maintaining solution homogeneity; and a metering pump connected to the antistatic agent feeding tank for precisely metering and delivering the antistatic agent solution to the reactor. Compared with the prior art, this utility model has advantages such as achieving precise metering and continuous feeding; multifunctional compatibility, adapting to antistatic agents with different properties; and improved reaction safety.

Description

Technical Field

[0001] This utility model relates to the field of antistatic technology, and in particular to a multifunctional antistatic agent feeding device that can continuously inject and accurately measure the agent. Background Technology

[0002] In the gas-phase olefin polymerization process, due to the frictional movement of powders and the presence of impurities such as water, oxygen, alcohols, aldehydes, ketones, and ethers in the hydrocarbon feedstock that can induce static electricity, a certain amount of static electricity is inevitably generated in the polymerization reactor. Once the static electricity in the polymerization reactor reaches a certain level, the stability of the polymerization reaction will be severely disrupted, and in severe cases, it may cause the plant to shut down. To ensure the stability of the polymerization reaction, a certain amount of antistatic agent needs to be continuously injected to control the static electricity in the reaction and stabilize the static electricity level in the reactor within a safe range.

[0003] In gas-phase olefin polymerization, the continuity and precision of the antistatic agent dosage added to the polymerization reactor are crucial to the stability of the polymerization reaction. Therefore, how to continuously and precisely meter the antistatic agent into the polymerization reactor is a pressing technical problem to be solved in this field.

[0004] Patent CN118976429A discloses an isooctane antistatic agent injection device and injection process, mainly including a blending tank, an injection module, a circulation module, and a control module. This invention improves the conductivity of isooctane products, reduces static electricity buildup, addresses the issue of quantitative injection of antistatic agents, and lowers safety risks during storage, transportation, handling, and operation. However, this device is not suitable for continuous injection of antistatic agents into reactors used in olefin polymerization processes.

[0005] Patent CN119303503A discloses a method for adding a polymerization stabilizer, mainly including: feeding an antistatic agent into a dilution container; feeding a diluent into the dilution container; mixing the antistatic agent and diluent in the dilution container to obtain a mixed solution; and conveying the mixed solution to the polymerization reactor. However, this system does not have the ability to continuously inject antistatic agents online. When the diluent initially prepared in the dilution container is used up, it needs to be stopped and prepared again.

[0006] Patent CN217856061U discloses a polyethylene fluidized bed antistatic agent injection device, mainly comprising a gas transmission port, a heating and insulation device, and an antistatic agent injection assembly. The gas transmission port is located on both sides of the heating and insulation device for inputting and outputting carrier gas. The antistatic agent injection assembly is used to add antistatic agent, which mixes with the passing carrier gas and is then carried into the fluidized bed to achieve electrostatic control of the fluidized bed, ensuring its long-term stable operation. The heating and insulation assembly provides the temperature environment required for the process. This device is a water- or alcohol-based antistatic agent injection device, suitable only for short-term suppression of high static electricity during the start-up phase of a gas-phase polyethylene plant, and not suitable for continuous injection during normal operation. Utility Model Content

[0007] The purpose of this invention is to overcome the shortcomings of the existing technology by providing a multifunctional antistatic agent feeding device that can continuously inject and accurately measure, achieving precise measurement and continuous feeding; multifunctional compatibility to adapt to antistatic agents with different properties; and improved reaction safety.

[0008] The objective of this utility model can be achieved through the following technical solutions:

[0009] This invention enables the continuous and precise metering of various antistatic agents to be added to the polymerization reactor, maintaining the concentration of antistatic agents in the polymerization reactor within a certain range as needed, thus ensuring the stability of electrostatics in the polymerization reaction.

[0010] This utility model provides a multifunctional antistatic agent feeding device capable of continuous injection and precise metering, comprising:

[0011] An antistatic agent dilution tank is used to receive and mix a high-viscosity first antistatic agent and a diluent to form a first antistatic agent dilution solution.

[0012] A nitrogen generator is connected to an antistatic agent dilution tank and is used to bubble and remove water and oxygen from the first antistatic agent dilution solution.

[0013] An antistatic agent feeding tank, connected to an antistatic agent dilution tank, is used to receive the first antistatic agent dilution solution after water and oxygen have been removed, or to directly receive the second antistatic agent.

[0014] A stirrer, installed inside the antistatic agent feeding tank, is used to maintain solution homogeneity;

[0015] A metering pump, connected to the antistatic agent feed tank, is used to accurately meter and deliver the antistatic agent solution to the reactor.

[0016] Furthermore, the first antistatic agent is a pure antistatic agent, mixed with a diluent at a ratio of 5%-30%.

[0017] Furthermore, the second antistatic agent is an antistatic agent white oil solution or an antistatic agent inert hydrocarbon solution.

[0018] Furthermore, the diluent is an inert hydrocarbon solvent selected from pentane, hexane, or isobutane.

[0019] Furthermore, the first antistatic agent is delivered to the antistatic agent dilution tank by a pump or nitrogen pressure.

[0020] Furthermore, the nitrogen generator operates for no less than 2 hours.

[0021] Furthermore, the pressure in the antistatic agent dilution tank during nitrogen purging is 20 kPaG-100 kPaG.

[0022] Furthermore, the metering pump is either a diaphragm pump or a screw pump. A screw pump is preferred.

[0023] Furthermore, the antistatic agent dilution tank is equipped with a discharge port for depressurization during nitrogen purging.

[0024] Furthermore, the liquid level display in the antistatic agent feeding tank triggers the start of the agitator.

[0025] The workflow is as follows:

[0026] The first antistatic agent is pumped or pressurized with nitrogen into the antistatic agent dilution tank. The diluent is added to the first antistatic agent dilution tank according to the required ratio, generally controlled between 5% and 30%. After the antistatic agent and diluent are pressurized, the nitrogen generator is started to bubble and mix the first antistatic agent and diluent added to the antistatic agent dilution tank, and to remove water and oxygen. The nitrogen generator should be running for at least 2 hours. During nitrogen bubbling, the antistatic agent dilution tank is depressurized through the vent. Note that during hydraulic pressure control, the pressure in the antistatic agent dilution tank should be maintained between 20 kPaG and 100 kPaG. The nitrogen generator is then shut off, and the dehydrated and oxygenated antistatic agent solution in the dilution tank is pumped into the antistatic agent feeding tank. The feeding tank is equipped with a stirrer; once the level indicator in the feeding tank appears, the stirrer is activated. The antistatic agent dilution solution in the feeding tank is then precisely metered by a metering pump and sent to the reactor.

[0027] The second antistatic agent is delivered to the antistatic agent feeding tank under nitrogen pressure. The antistatic agent feeding tank is equipped with a stirrer, which is activated once the liquid level indicator in the tank begins to show. The diluted antistatic agent solution in the feeding tank is then precisely metered by a metering pump and delivered to the reactor.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] (1) Achieve accurate metering and continuous feeding. Using screw pumps or diaphragm pumps as metering pumps reduces the feeding error of antistatic agents, which is superior to traditional gravity filling or ordinary centrifugal pumps; through the coordinated control of liquid level linkage agitator and metering pump, uninterrupted feeding is achieved, avoiding the static fluctuations caused by traditional batch feeding.

[0030] (2) Multifunctional compatibility. It can adapt to antistatic agents with different physical properties. The first antistatic agent (high viscosity pure antistatic agent) needs to be diluted online, while the second antistatic agent (low viscosity solution) can be directly injected. One set of equipment can meet the two feeding modes, avoiding the trouble of switching to special equipment in traditional processes.

[0031] (3) Improve reaction safety. It has an impurity removal mechanism. The nitrogen generator forces bubbling for more than 2 hours in the first antistatic agent dilution stage. Pressure control ensures that impurities such as water and oxygen are efficiently removed, and the impurity content is reduced to the ppm level, avoiding side reactions or catalyst poisoning caused by impurities. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a multifunctional antistatic agent feeding device that can continuously inject and accurately measure the agent.

[0033] Figure labels: 1-Antistatic agent dilution tank; 2-Nitrogen generator; 3-Antistatic agent feeding tank; 4-Agitator; 5-Metering pump. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0035] Example 1

[0036] This embodiment provides a multifunctional antistatic agent feeding device capable of continuous injection and precise metering, such as... Figure 1 As shown, it includes:

[0037] Antistatic agent dilution tank 1 is used to receive and mix a high-viscosity first antistatic agent and a diluent to form a first antistatic agent dilution solution;

[0038] Nitrogen generator 2 is connected to antistatic agent dilution tank 1 and is used to bubble and remove water and oxygen from the first antistatic agent dilution solution.

[0039] The antistatic agent feeding tank 3 is connected to the antistatic agent dilution tank 1 and is used to receive the first antistatic agent dilution solution after water and oxygen have been removed or to directly receive the second antistatic agent.

[0040] A stirrer 4 is installed inside the antistatic agent feeding tank 3 to maintain the homogeneity of the solution;

[0041] Metering pump 5 is connected to antistatic agent feeding tank 3 and is used to accurately meter and deliver the antistatic agent solution to the reactor.

[0042] In a specific embodiment, the first antistatic agent is a pure antistatic agent, which is mixed with a diluent at a ratio of 5%-30%.

[0043] In a specific embodiment, the second antistatic agent is an antistatic agent white oil solution or an antistatic agent inert hydrocarbon solution.

[0044] In a specific embodiment, the diluent is an inert hydrocarbon solvent selected from pentane, hexane, or isobutane.

[0045] In a specific embodiment, the first antistatic agent is pumped or pressurized with nitrogen into the antistatic agent dilution tank 1.

[0046] In a specific implementation, the nitrogen generator 2 operates for no less than 2 hours.

[0047] In a specific embodiment, the pressure of the antistatic agent dilution tank 1 during nitrogen purging is 20 kPaG-100 kPaG.

[0048] In a specific embodiment, the metering pump 5 is either a diaphragm pump or a screw pump. A screw pump is preferred.

[0049] In a specific embodiment, the antistatic agent dilution tank 1 is provided with a discharge port for depressurization during nitrogen purging.

[0050] In a specific embodiment, the liquid level display of the antistatic agent feeding tank 3 triggers the start of the agitator 4.

[0051] The workflow is as follows:

[0052] The first antistatic agent is pumped or pressurized with nitrogen into the antistatic agent dilution tank 1. The diluent is added to the first antistatic agent dilution tank according to the required ratio, generally controlled between 5% and 30% for the antistatic agent and diluent. After the antistatic agent and diluent are pressurized, the nitrogen generator 2 is started to bubble and mix the first antistatic agent and diluent added to the antistatic agent dilution tank 1, and to remove water and oxygen. The nitrogen generator 2 should be running for at least 2 hours. During nitrogen bubbling, the antistatic agent dilution tank 1 is depressurized through the discharge port. Note that during hydraulic pressure control, the pressure in the antistatic agent dilution tank 1 should be maintained between 20 kPaG and 100 kPaG. The nitrogen generator 2 is then shut off, and the dehydrated and oxygenated antistatic agent solution in the antistatic agent dilution tank 1 is pumped into the antistatic agent feeding tank 3. The antistatic agent feeding tank 3 is equipped with a stirrer 4. Once the liquid level indicator in the antistatic agent feeding tank 3 begins to appear, the stirrer 4 is started. The diluted antistatic agent solution in the antistatic agent feeding tank 3 is accurately metered by the metering pump 5 and then sent into the reactor.

[0053] The second antistatic agent is delivered to the antistatic agent feeding tank 3 under nitrogen pressure. The antistatic agent feeding tank 3 is equipped with a stirrer 4. Once the liquid level indicator in the antistatic agent feeding tank 3 begins to appear, the stirrer 4 is activated. The diluted antistatic agent solution in the antistatic agent feeding tank 3 is precisely metered by the metering pump 5 and then sent to the reactor.

[0054] Components not described in detail in this embodiment are all existing components that can be purchased through public channels.

[0055] The above description of the embodiments is provided to enable those skilled in the art to understand and use the utility model. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present utility model is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present utility model without departing from its scope should be within the protection scope of the present utility model.

Claims

1. A multifunctional antistatic agent feeding device capable of continuous injection and precise metering, characterized in that, include: An antistatic agent dilution tank (1) is used to receive and mix a first antistatic agent and a diluent to form a first antistatic agent dilution solution; A nitrogen generator (2) is connected to an antistatic agent dilution tank (1) for bubbling and removing water and oxygen from the first antistatic agent dilution solution. An antistatic agent feeding tank (3) is connected to an antistatic agent dilution tank (1) and is used to receive the first antistatic agent dilution solution after water and oxygen have been removed or to directly receive the second antistatic agent. A stirrer (4) is installed inside the antistatic agent feeding tank (3) to maintain the homogeneity of the solution; A metering pump (5) is connected to an antistatic agent feeding tank (3) for accurately metering and delivering the antistatic agent solution to the reactor.

2. The multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The first antistatic agent is a pure antistatic agent, which is mixed with a diluent at a ratio of 5%-30%.

3. The multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The second antistatic agent is an antistatic agent white oil solution or an antistatic agent inert hydrocarbon solution.

4. The multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The diluent is an inert hydrocarbon solvent selected from pentane, hexane, or isobutane.

5. The multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The first antistatic agent is pumped or compressed with nitrogen into the antistatic agent dilution tank (1).

6. The multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The nitrogen generator (2) operates for no less than 2 hours.

7. The multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The pressure of the antistatic agent dilution tank (1) during nitrogen purging is 20 kPaG-100 kPaG.

8. A multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The metering pump (5) is a diaphragm pump or a screw pump.

9. A multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The antistatic agent dilution tank (1) is equipped with a discharge port for depressurization during nitrogen purging.

10. A multifunctional antistatic agent feeding device capable of continuous injection and precise metering according to claim 1, characterized in that, The liquid level display of the antistatic agent feeding tank (3) triggers the start of the agitator (4).

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