Chemical additive preparation system and method

Abstract

The invention discloses a chemical additive preparation system and method, and belongs to the technical field of chemical additive preparation, the system comprises a metering pump, a preparation tank, a stroke regulator, a flowmeter, a control device, a first storage tank and a second storage tank, the first storage tank is used for storing a solvent, and the second storage tank is used for storing a raw material catalyst or a raw material initiator; the control end of the pump head of the metering pump is connected with the control device through the stroke regulator and the flowmeter in sequence; the outlet end of the pump head is connected with the preparation tank; the control device responds to an external signal, determines a raw material flow ratio of a target catalyst or a target initiator, and sends a flow control signal to the corresponding flow meter according to the raw material flow ratio; the flow meter sends a flow control signal to the corresponding stroke regulator; and the stroke adjuster adjusts the stroke of the corresponding pump head according to the flow control signal, so that the metering pump conveys the solvent, the raw material catalyst and / or the raw material initiator meeting the raw material flow ratio from the first storage tank and the second storage tank to the preparation tank.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of chemical aid preparation, and particularly relates to a chemical aid preparation system and method. BACKGROUND

[0002] Catalysts or initiators are common chemical aids. In chemical plants with reaction units, catalysts or initiators are indispensable key components in the production process, which have a decisive role in reaction efficiency, product performance and process economy. In polyolefin plants, catalyst or initiator preparation units are generally provided, and a plurality of catalysts (co-catalysts) or initiators are generally prepared into a required concentration according to a specified proportion and then injected into a reactor. The accuracy of the catalyst or initiator preparation concentration has a crucial influence on the control of the polymerization reaction, product performance and plant safety.

[0003] In particular, for high-pressure ethylene polymerization processes, at least two peroxides are generally used as initiators. If the concentration is too low during the preparation of the initiators, the active free radicals are not replenished quickly enough, which can cause an increase in high-molecular-weight, low-melt-index polymers, poor product flowability, and easy occurrence of reactor wall sticking. If the concentration is too high during the preparation of the initiators, the polymerization reaction speed is too fast, the heat release is intense, and even the decomposition of ethylene to cause overpressure risk can occur. Meanwhile, peroxides have the characteristics of decomposition and explosion at high temperatures, and therefore, efficient and accurate metering preparation of peroxide initiators through automatic control is of great significance for reducing personnel operation risk and labor intensity and ensuring long-period stable operation of the high-pressure polymerization process.

[0004] In related technologies, the preparation of catalysts or initiators is generally manually carried out by operators through manual carrying and injection, which can easily cause inaccurate flow ratio of raw materials of the catalysts or initiators. SUMMARY

[0005] Embodiments of the present application provide a chemical aid preparation system and method, which can at least to some extent realize automatic preparation of catalysts or initiators and improve the accuracy of the flow ratio of raw materials of the catalysts or initiators.

[0006] Other characteristics and advantages of the present application will become apparent from the following detailed description, or will be learned by practice of the present application.

[0007] According to a first aspect of the embodiments of the present application, a chemical additive preparation system is provided, the chemical additive including a target catalyst or a target initiator, the system comprising: a metering pump, a preparation tank, a stroke regulator, a flow meter, a control device, a first storage tank and a second storage tank, the first storage tank being configured to store a solvent, the second storage tank being configured to store a raw catalyst or a raw initiator, the preparation tank being configured to store the target catalyst or the target initiator, the metering pump comprising a pump head, an inlet end of the pump head being connected to the first storage tank or the second storage tank, a control end of the pump head being connected to the control device via the stroke regulator and the flow meter in sequence, and an outlet end of the pump head being connected to the preparation tank; wherein,

[0008] the control device being configured to determine a raw material flow ratio of the target catalyst or the target initiator in response to an external signal, and to send a flow control signal to the corresponding flow meter according to the raw material flow ratio;

[0009] the flow meter being configured to send the flow control signal to the corresponding stroke regulator;

[0010] the stroke regulator being configured to adjust the stroke of the corresponding pump head according to the flow control signal, so that the metering pump delivers the solvent, the raw catalyst and / or the raw initiator meeting the raw material flow ratio from the first storage tank and the second storage tank to the preparation tank.

[0011] In some embodiments, the number of the second storage tanks is multiple, the number of the pump heads of each metering pump is multiple, the number of the preparation tanks is multiple, and the number of the pump heads is the same as the number of the preparation tanks.

[0012] In some embodiments, the pump head of each metering pump comprises a first pump head, a second pump head and a third pump head, and the preparation tank comprises a first preparation tank, a second preparation tank and a third preparation tank; wherein,

[0013] the outlet end of the first pump head of each metering pump is connected to the first preparation tank through a pipeline;

[0014] the outlet end of the second pump head of each metering pump is connected to the second preparation tank through a pipeline;

[0015] the outlet end of the third pump head of each metering pump is connected to the third preparation tank through a pipeline.

[0016] In some embodiments, the chemical additive preparation system further comprises a static mixer, the static mixer being arranged on the pipeline after the pipelines are merged.

[0017] In some embodiments, the chemical additive preparation system further comprises a cooling water jacket and a cooling tube, the cooling water jacket being configured to cool the first storage tank, the second storage tank and the metering pump, and the cooling tube being configured to cool the pipeline.

[0018] In some embodiments, the chemical additive preparation system further comprises a filter, the filter being arranged at the inlet end of the metering pump.

[0019] In some embodiments, the metering pump further comprises a variable frequency motor, which is connected with the pump head and the control device respectively.

[0020] In some embodiments, the chemical additive preparation system further comprises a liquid level sensor arranged in the preparation tank, which is configured to detect a liquid level signal of the target catalyst or the target initiator in the preparation tank and send the liquid level signal to the control device; and the control device is further configured to control the stroke regulator according to the liquid level signal.

[0021] In some embodiments, the control device comprises a formula selection button corresponding to the formula of the target catalyst or the target initiator, which is configured to receive an external signal output by an external formula-based device.

[0022] According to a second aspect of the embodiments of the present application, a chemical additive preparation method is provided, which is applied to the chemical additive preparation system described above, and the chemical additive preparation method comprises:

[0023] The control device determines the raw material flow ratio of the target catalyst or the target initiator in response to the external signal, and sends a flow control signal to the corresponding flow meter according to the raw material flow ratio;

[0024] The flow meter sends the flow control signal to the corresponding stroke regulator;

[0025] The stroke regulator adjusts the stroke of the corresponding pump head according to the flow control signal, so that the metering pump delivers the solvent, the raw material catalyst and / or the raw material initiator meeting the raw material flow ratio from the first tank and the second tank to the preparation tank.

[0026] In the present application, through the design of the chemical additive preparation system, the automatic control of catalyst or initiator preparation is realized, and at the same time, the metering accuracy of each solvent, raw material catalyst and / or raw material initiator in the preparation process is improved, thereby improving the accuracy of the raw material flow ratio of the target catalyst or the target initiator, reducing the personnel operation risk and labor intensity, and ensuring the smooth operation of the high-pressure polymerization reaction process.

[0027] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0028] The drawings incorporated into the specification and forming a part thereof, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. In the drawings:

[0029] Figure 1 A schematic diagram of a system for preparing a chemical additive according to some embodiments of the present application is shown;

[0030] Figure 2 A flowchart of a method for preparing a chemical additive according to some embodiments of the present application is shown;

[0031] BRIEF DESCRIPTION OF DRAWINGS

[0032] 1 - first tank; 2a ~ 2c - second tank; 3a ~ 3d - metering pump; 4a ~ 4d - stroke regulator; 5a ~ 5d - flow meter; 6 - control device; 7 - preparation tank. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0034] In addition, the described features, structures or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to give a full understanding of the embodiments of the present application. However, those skilled in the art will realize that the technical solutions of the present application can be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. can be used. In other cases, well-known methods, devices, implementations or operations are not shown or described in detail to avoid obscuring the aspects of the present application.

[0035] The block diagram shown in the drawings is only a functional entity, which does not necessarily correspond to a physically independent entity. That is, these functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0036] The flowchart shown in the drawings is only an exemplary description, which does not necessarily include all contents and operations / steps, and does not necessarily be executed in the described order. For example, some operations / steps can be further decomposed, and some operations / steps can be combined or partially combined, so that the actual execution order can be changed according to the actual situation.

[0037] In order for those skilled in the art to better understand the present application, first Figure 1 The application scenarios involved in the present application are briefly described.

[0038] Catalyst or initiator is a common chemical additive, and efficient and accurate metering of catalyst and / or initiator through automatic control is of great significance to reduce the risk and labor intensity of personnel operation and ensure long-term stable operation of high-pressure polymerization process.

[0039] In one related technology, an initiator preparation system is proposed, which relies on multiple groups of regulating valves to control the ratio of initiator and solvent. The number of regulating valves is large, the operation stability is reduced, and a pump needs to be continuously circulated to maintain the outlet pressure. The circulation amount is much larger than the output amount, causing energy waste. At the same time, a large amount of circulation can easily cause the temperature of the initiator to rise, which has the risk of deactivation and decomposition.

[0040] In another related technology, a high-pressure polymerization reactor initiator feeding device is proposed. The automatic metering system is an automatic stroke control metering system imported from Germany, model DE LOCKE, which limits the specific model, but does not involve the details of how to automatically meter and prepare multiple initiators and solvents. At the same time, it can only prepare one ratio of initiator solution at a time, and when multiple ratios of initiator solution are needed, it can only be prepared sequentially, which takes a long time to operate and has low preparation efficiency.

[0041] In yet another related technology, an initiator injection system is proposed, which includes a tank group composed of a mixing tank and a buffer tank. The initiator is manually added by an operator or automatically prepared through an automatic control loop, but the device does not involve the details of the automatic preparation device.

[0042] The embodiment of the application provides a chemical additive preparation system and method, the system comprises: a metering pump, a preparation tank, a stroke regulator, a flow meter, a control device, a first storage tank and a second storage tank, the first storage tank is used for storing a solvent, the second storage tank is used for storing a raw material catalyst or a raw material initiator, the preparation tank is used for storing a target catalyst or a target initiator, the metering pump comprises a pump head, an inlet end of the pump head is connected with the first storage tank or the second storage tank, a control end of the pump head is connected with the control device in sequence through the stroke regulator and the flow meter, and an outlet end of the pump head is connected with the preparation tank; wherein the control device is used for determining a raw material flow ratio of the target catalyst or the target initiator in response to an external signal, and sending a flow control signal to a corresponding flow meter according to the raw material flow ratio; the flow meter is used for sending the flow control signal to a corresponding stroke regulator; and the stroke regulator is used for adjusting the stroke of the corresponding pump head according to the flow control signal, so that the metering pump transports the solvent, the raw material catalyst and / or the raw material initiator meeting the raw material flow ratio from the first storage tank and the second storage tank to the preparation tank. Through the design of the chemical additive preparation system, automatic control of catalyst or initiator preparation is realized, meanwhile, the metering accuracy of each solvent, raw material catalyst and / or raw material initiator in the preparation process is improved, and then the accuracy of the raw material flow ratio of the target catalyst or the target initiator is improved, the personnel operation risk and labor intensity are reduced, and the smooth running of the high-pressure polymerization reaction process is ensured.

[0043] Figure 1 The architecture diagram of the chemical additive preparation system according to some embodiments of the application is shown. Figure 1As shown, a chemical additive preparation system is provided, the chemical additive including a target catalyst or a target initiator, the chemical additive preparation system comprising: metering pumps (3a, 3b, 3c, 3d), a preparation tank 7, stroke regulators (4a, 4b, 4c, 4d), flow meters (5a, 5b, 5c, 5d), a control device 6, a first storage tank 1 for storing a solvent, and second storage tanks (2a, 2b, 2c) for storing raw catalyst or raw initiator, the preparation tank 7 being used for storing the target catalyst or the target initiator, the metering pumps (3a, 3b, 3c, 3d) comprising pump heads (not shown), the inlet end of the pump head being connected with the first storage tank 1 or the second storage tank (2a, 2b, 2c), the control end of the pump head being connected with the control device 6 in sequence through the stroke regulator (4a, 4b, 4c, 4d) and the flow meter (5a, 5b, 5c, 5d), and the outlet end of the pump head being connected with the preparation tank 7; wherein the control device 6 is configured to determine a raw material flow ratio of the target catalyst or the target initiator in response to an external signal, and send a flow control signal to the corresponding flow meter (5a, 5b, 5c, 5d) according to the raw material flow ratio; the flow meter (5a, 5b, 5c, 5d) is configured to send the flow control signal to the corresponding stroke regulator (4a, 4b, 4c, 4d); and the stroke regulator (4a, 4b, 4c, 4d) is configured to adjust the stroke of the corresponding pump head according to the flow control signal, so that the metering pump (3a, 3b, 3c, 3d) delivers the solvent, the raw catalyst and / or the raw initiator meeting the raw material flow ratio from the first storage tank 1 and the second storage tank (2a, 2b, 2c) to the preparation tank.

[0044] The stroke regulator (4a, 4b, 4c, 4d) can be integrally arranged with the pump head or arranged independently of the pump head, and the position of the stroke regulator is not limited in the embodiments of the present application. The stroke regulator (4a, 4b, 4c, 4d) is arranged in one-to-one correspondence with the pump head, so as to independently adjust the stroke of the corresponding pump head.

[0045] The flow meter (5a, 5b, 5c, 5d) can be arranged on the pipeline at the outlet end of the pump head, and can have a flow accumulation function and a control function. In some embodiments, a high-precision mass flow meter can be selected, for example, a mass flow meter with a precision of ±0.1%.

[0046] The control device 6 can pre-set the raw material flow ratio of the solvent, raw material catalyst and / or raw material initiator corresponding to different formulations according to production needs. When a user selects a certain formulation through the control device 6, the control device 6 determines the target catalyst or target initiator raw material flow ratio in response to the external signal of the user selecting the formulation, and sends a flow control signal to the corresponding flow meter (5a, 5b, 5c, 5d) according to the raw material flow ratio; after the flow meter (5a, 5b, 5c, 5d) receives the flow control signal, the flow value is set according to the flow control signal, and the flow control signal is sent to the corresponding stroke regulator (4a, 4b, 4c, 4d).

[0047] It should be noted that, Figure 1 Although four stroke regulators, four flow meters, one first tank, three second tanks and twelve pump heads are shown in the above embodiment, Figure 1 This is only one embodiment of the present application, and is used to limit the number of stroke regulators, flow meters, first tanks, second tanks and pump heads in the present application.

[0048] In some embodiments, the number of second tanks is multiple, the number of pump heads of each metering pump is multiple, the number of preparation tanks is multiple, and the number of pump heads is the same as the number of preparation tanks.

[0049] In the implementation process, the number of second tanks is usually 3-5, and the preparation of 3-5 target catalysts and / or target initiators can be realized simultaneously or in batches. The number of pump heads can be 2 or more, the outlet end of each pump head is connected with a preparation tank, and each preparation tank is connected with the injection point of the target catalyst and / or target initiator of the polymerization reactor, so the number of preparation tanks is the same as the number of injection points of the polymerization reactor.

[0050] In some embodiments, the pump head of each metering pump includes a first pump head, a second pump head and a third pump head, and the preparation tank includes a first preparation tank, a second preparation tank and a third preparation tank; wherein the pipelines of the outlet ends of the first pump heads of each metering pump converge to the first preparation tank; the pipelines of the outlet ends of the second pump heads of each metering pump converge to the second preparation tank; and the pipelines of the outlet ends of the third pump heads of each metering pump converge to the third preparation tank.

[0051] By providing multiple pump heads for each metering pump, one kind of solvent, raw material catalyst or raw material initiator is independently delivered by each pump head, and the pipelines of the outlet ends of the pump heads corresponding to different target catalysts or target initiators converge to the preparation tank, thereby realizing multi-channel accurate betting and improving the accuracy of the raw material flow ratio of the target catalyst or target initiator.

[0052] In some embodiments, the preparation system of the chemical additive further comprises a static mixer (not shown in the figure), which is arranged on the converged pipeline.

[0053] It can be understood that the static mixer is a high-efficiency mixing device without moving parts. Through special internal structure design, the fluid generates cutting, rotation, splitting and recombination when flowing through, so as to realize rapid, uniform mixing, reaction or mass transfer. The static mixer is arranged on the pipeline at the outlet end of the pump head to the preparation tank, which is beneficial to the high-efficiency mixing of the solvent and different raw material catalysts or the solvent and different raw material initiators.

[0054] In some embodiments, the chemical additive preparation system further comprises a cooling water jacket (not shown in the figure) for cooling the first tank, the second tank and the metering pump, and a cooling pipe (not shown in the figure) for cooling the pipeline.

[0055] In the implementation process, for initiators with decomposition and explosion risk at high temperature, such as peroxide initiators, cooling water jackets and cooling pipes can be arranged for cooling. For example, double-layer jackets can be welded or assembled on the outer walls of the first tank, the second tank and the metering pump, and cooling water (such as 5-10℃ ethylene glycol solution) is introduced into the jackets. The jackets can be designed as spiral flow channels or segmented flow channels to ensure uniform distribution of the cooling water and avoid local overheating. Temperature sensors can be arranged at the inlet and outlet of the jacket to interlock and adjust the flow of the cooling water, reduce the temperature rise in the preparation process, and ensure that the temperature of the first tank, the second tank and the metering pump is within a safe range. In the implementation process, the pipeline can also be indirectly cooled by winding the cooling pipe around the outer wall of the pipeline to ensure that the temperature of the pipeline is within a safe range.

[0056] In some embodiments, the chemical additive preparation system further comprises a filter (not shown in the figure) arranged at the inlet end of the metering pump for filtering the solvent, the raw material catalyst or the raw material initiator.

[0057] In some embodiments, the chemical additive preparation system further comprises a shut-off valve (not shown in the figure) arranged at the inlet end and the outlet end of the pump head to facilitate maintenance of the pump head.

[0058] In some embodiments, the metering pump further comprises a variable frequency motor (not shown in the figure) connected with the pump head and the control device respectively. The variable frequency motor can be combined with the stroke adjuster to jointly adjust the flow of the solvent, the raw material catalyst or the raw material initiator delivered by the metering pump, so as to further improve the metering accuracy of the solvent, the raw material catalyst or the raw material initiator.

[0059] In some embodiments, the chemical additive dispensing system further comprises a liquid level sensor (not shown in the figure) disposed in the dispensing tank for detecting a liquid level signal of the target catalyst or the target initiator in the dispensing tank and sending the liquid level signal to the control device; the control device is further configured to control the stroke regulator according to the liquid level signal.

[0060] It can be understood that when the target catalyst or the target initiator in the dispensing tank reaches a certain liquid level (for example, 90%), the control device can set the stroke regulator corresponding to the pump head to zero to stop the corresponding pump head from feeding.

[0061] In some embodiments, the control device comprises a formula selection button corresponding to the formula of the target catalyst or the target initiator, and the formula selection button is configured to receive an external signal output based on the formula.

[0062] In the implementation process, a plurality of formula selection buttons can be arranged on the panel of the control device, each formula selection button corresponding to a formula, and a user can realize the automatic metering and dispensing of the chemical additive of different formulas by selecting the formula selection button.

[0063] Referring back to Figure 1In some embodiments, the chemical auxiliary preparation system comprises a first tank 1 for storing solvent, a second tank (2a, 2b, 2c) for storing different types of peroxide initiators, the first tank 1 and the second tank (2a, 2b, 2c) are respectively provided with a metering pump (3a, 3b, 3c, 3d) with three pump heads, and the outlet ends of the first tank 1 and the second tank (2a, 2b, 2c) are respectively connected with the inlet ends of the pump heads of the corresponding metering pump (3a, 3b, 3c, 3d) through pipelines. The number of pump heads of each pump in the metering pump (3a, 3b, 3c, 3d) corresponds to the number of target initiator preparation tanks downstream and also corresponds to the three injection points of the target initiator of the polymerization reactor. Each pump head of the metering pump (3a, 3b, 3c, 3d) is provided with a stroke adjuster (4a, 4b, 4c, 4d), and the stroke adjuster (4a, 4b, 4c, 4d) of each pump head can respectively receive a flow control signal and be independently adjusted. The pipelines of the outlet ends of pump head 1, the outlet ends of pump head 2 and the outlet ends of pump head 3 of each pump in the metering pump (3a, 3b, 3c, 3d) are sequentially merged, i.e. the solvent is mixed with different types of peroxide initiators respectively and sent to the corresponding target initiator preparation tank 7 downstream. A flow meter (5a, 5b, 5c, 5d) with flow accumulation function and control function is arranged on the pipeline of the outlet end of pump head 1, pump head 2 and pump head 3 of each pump in the metering pump (3a, 3b, 3c, 3d), and each flow meter (5a, 5b, 5c, 5d) outputs a flow control signal to the stroke adjuster (4a, 4b, 4c, 4d) of the corresponding pump head to automatically adjust the stroke of the corresponding pump head to meet the required flow of each initiator. The control device 6 is provided with the raw material flow ratio of each formula corresponding to the solvent and different types of peroxide initiators, and is provided with an initiator formula selection button, when a certain formula is selected, the flow setting value of each flow meter (5a, 5b, 5c, 5d) is automatically and simultaneously set.

[0064] The chemical auxiliary preparation system provided by the embodiments of the present application has at least the following beneficial effects compared with the above related art:

[0065] 1. The automatic metering and preparation of different formula chemical auxiliaries is realized, the operation risk and safety hazard of traditional manual handling and injection are avoided, and the labor intensity of the operator is reduced.

[0066] 2. By independently adjusting the strokes of the pump heads of the metering pump, the raw material flow ratio of the target catalyst or target initiator can be controlled, the ratio control is more accurate compared with traditional manual injection, the risk of reaction process temperature runaway or wall sticking caused by inaccurate raw material flow ratio is reduced, and the operation cycle and operation stability of the reaction process are improved.

[0067] 3. The metering pump with multiple pump heads does not need to maintain a minimum stable operating flow rate, does not need to circulate continuously, and only outputs the flow rate required by the formula. This reduces the energy consumption of the centrifugal pump in the existing device, which needs to maintain a circulation volume far greater than the output volume, and the temperature rise during the preparation process, thereby reducing the risk of high-temperature deactivation or decomposition of the target catalyst or target initiator.

[0068] 4. The output flow of each pump head of the metering pump can be adjusted independently and the materials can be fed simultaneously. That is, target catalysts or target initiators with different raw material flow ratios can be prepared at the same time. Compared with the solution of only being able to prepare one target catalyst or target initiator ratio at a time, the preparation efficiency is higher and the operation time is saved.

[0069] Figure 2 The following is a flow chart showing a method for preparing chemical additives according to some embodiments of the present application. Figure 2 As shown, a method for preparing a chemical additive is provided, which is applied to the above-mentioned chemical additive preparation system, and the method includes the following steps:

[0070] Step 201: The control device determines the raw material flow ratio of the target catalyst or target initiator in response to an external signal, and sends a flow control signal to the corresponding flow meter according to the raw material flow ratio;

[0071] Step 202: The flow meter sends a flow control signal to the corresponding stroke regulator;

[0072] In step 203, the stroke regulator adjusts the stroke of the corresponding pump head according to the flow control signal so that the metering pump delivers the solvent, raw material catalyst and / or raw material initiator that meet the raw material flow ratio from the first storage tank and the second storage tank to the preparation tank.

[0073] During implementation, the raw material flow ratios for target catalysts or target initiators corresponding to different formulations can be set in the control device according to production needs. The user can select the desired formulation using the formulation selection button on the control device. The control device determines the raw material flow ratio corresponding to the formulation and sends flow control signals to the corresponding flow meters based on the raw material flow ratio. The flow control signals from each flow meter are then sent to the stroke regulator of the corresponding pump head, which automatically adjusts the stroke of each pump head to control the output flow of each solvent, raw material catalyst, and / or raw material initiator.

[0074] The solvent, raw material catalyst and / or raw material initiator at a set flow rate are merged through a pipeline, mixed to form a target catalyst or target initiator with a required formulation concentration, and then transported to a downstream preparation tank.

[0075] When the target catalyst or target initiator in the preparation tank reaches a certain liquid level, the metering pump stops feeding, and thus a preparation cycle is completed, and the target catalyst or target initiator in the preparation tank is transported to the polymerization reactor by the injection pump.

[0076] In combination Figure 1 and Figure 2 In some embodiments, the first tank 1 stores solvent, and the second tanks (2a, 2b, 2c) store three different types of peroxide initiators respectively. The formula A is as follows: the set values of the three flow meters 5a corresponding to the three pump heads of the metering pump 3a downstream of the first tank 1 are 150 kg / h, 120 kg / h, and 150 kg / h respectively; the set values of the three flow meters 5b corresponding to the three pump heads of the metering pump 3b downstream of the first tank 1 are 50 kg / h, 45 kg / h, and 25 kg / h respectively; the set values of the three flow meters 5c corresponding to the three pump heads of the metering pump 3c downstream of the first tank 1 are 15 kg / h, 15 kg / h, and 30 kg / h respectively; the set values of the three flow meters 5d corresponding to the three pump heads of the metering pump 3d downstream of the first tank 1 are 35 kg / h, 40 kg / h, and 45 kg / h respectively; the formula A is selected in the control device 6 by the formula selection button, the initiator automatic metering preparation sequence control program is started, and each flow meter in 5a, 5b, 5c, and 5d is assigned with the flow set value of each component in the formula A. The flow control signal of the flow set value of each flow meter is sent to the stroke adjusting device (4a, 4b, 4c, 4d) of the corresponding pump head, the stroke of each pump head is automatically adjusted to the corresponding value, and the solvent and each raw material initiator are controlled to be output according to the formula A. After the solvent and each raw material initiator under the formula A are combined through the pipeline, the target initiator required by the formula A is formed, and is sent to the downstream initiator preparation tank 7. When the target initiator in the initiator preparation tank 7 reaches 90% of the liquid level, the set values of the flow meters corresponding to the initiator preparation tank 7 are set to zero, and the pump heads of the corresponding solvent and raw material initiators stop feeding, and thus a preparation cycle is completed, and the sequence control program ends.

[0077] The preparation method of the chemical additive of the embodiments of the present application automatically assigns the flow set value of the flow meter according to the external signal, adjusts the stroke of each pump head of the metering pump, realizes one-time preparation of multiple chemical additives with different proportions, has the characteristics of high automation degree, accurate metering, and high preparation efficiency, and only outputs the required flow of the solvent, raw material catalyst, and / or raw material initiator, and has low temperature rise and energy consumption during the preparation process.

[0078] The above merely provides an example of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall fall into the scope of claims of the present application.

Claims

1. A chemical additive preparation system, characterized in that: The chemical auxiliary agent includes a target catalyst or a target initiator. The system includes: a metering pump, a preparation tank, a stroke regulator, a flow meter, a control device, a first storage tank and a second storage tank. The first storage tank is used to store a solvent, the second storage tank is used to store a raw catalyst or a raw initiator, and the preparation tank is used to store the target catalyst or the target initiator. The metering pump includes a pump head, the inlet end of the pump head is connected to the first storage tank or the second storage tank, the control end of the pump head is connected to the control device via the stroke regulator and the flow meter in sequence, and the outlet end of the pump head is connected to the preparation tank; wherein, The control device is used to determine the raw material flow ratio of the target catalyst or the target initiator in response to an external signal, and send a flow control signal to the corresponding flow meter according to the raw material flow ratio; The flow meter is used to send the flow control signal to the corresponding stroke regulator; The stroke regulator is used to adjust the stroke of the corresponding pump head according to the flow control signal so that the metering pump can transport the solvent, raw material catalyst and / or raw material initiator that meets the raw material flow ratio from the first storage tank and the second storage tank to the preparation tank.

2. The chemical additive preparation system according to claim 1, characterized in that: There are multiple second storage tanks, each metering pump has multiple pump heads, there are multiple preparation tanks, and the number of the pump heads is the same as the number of the preparation tanks.

3. The chemical additive preparation system according to claim 2, characterized in that: The pump head of each metering pump includes a first pump head, a second pump head and a third pump head, and the preparation tank includes a first preparation tank, a second preparation tank and a third preparation tank; wherein, The pipeline at the outlet end of the first pump head of each metering pump merges into the first preparation tank; The pipeline at the outlet end of the second pump head of each metering pump merges into the second preparation tank; The pipeline at the outlet end of the third pump head of each metering pump merges into the third preparation tank.

4. The chemical additive preparation system according to claim 3, characterized in that: Also includes: A static mixer is provided on the pipeline after the merging.

5. The chemical additive preparation system according to claim 3, characterized in that: Also includes: A cooling water jacket and a cooling pipe, wherein the cooling water jacket is used to cool the first storage tank, the second storage tank and the metering pump, and the cooling pipe is used to cool the pipeline.

6. The chemical auxiliary agent preparation system according to any one of claims 1 to 5, characterized in that: Also includes: A filter is provided at the inlet end of the metering pump.

7. The chemical auxiliary agent preparation system according to any one of claims 1 to 5, characterized in that: The metering pump further comprises a variable frequency motor, which is connected to the pump head and the control device respectively.

8. The chemical auxiliary agent preparation system according to any one of claims 1 to 5, characterized in that: Also includes: A liquid level sensor is provided in the preparation tank, and is used to detect the liquid level signal of the target catalyst or target initiator in the preparation tank and send the liquid level signal to the control device; the control device is also used to control the stroke regulator according to the liquid level signal.

9. The chemical auxiliary agent preparation system according to any one of claims 1 to 5, characterized in that: The control device includes a recipe selection button, which corresponds one-to-one to the recipe of the target catalyst or target initiator, and is used to receive the external signal output based on the recipe.

10. A method for preparing a chemical auxiliary agent, applied to the chemical auxiliary agent preparation system according to any one of claims 1 to 9, the method comprising: The control device determines the raw material flow ratio of the target catalyst or the target initiator in response to the external signal, and sends a flow control signal to the corresponding flow meter according to the raw material flow ratio; The flow meter sends the flow control signal to the corresponding stroke regulator; The stroke regulator adjusts the stroke of the corresponding pump head according to the flow control signal so that the metering pump can transport the solvent, raw material catalyst and / or raw material initiator that meet the raw material flow ratio from the first storage tank and the second storage tank to the preparation tank.

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