Polyolefin fluidized bed reactor and stable operation method, system, terminal and medium

Abstract

The present invention provides a polyolefin fluidized bed reactor and a stable operation method and system. Based on control conditions, a continuous discharge line is added to the middle of the fluidized bed reactor. The ratio of the mass flow rate m2 of the intermittent discharge line to the mass flow rate m1 of the continuous discharge line is dynamically controlled based on characteristic parameters of a detection signal, thereby maintaining stable operation of the fluidized bed. A corresponding terminal and medium are also provided. By dynamically adjusting the intermittent / continuous discharge ratio online, the present invention not only avoids deterioration of fluidization quality and reactor agglomeration, but also enables high-level operation, improving production capacity and ensuring long-term stable operation of the reactor.

Description

Technical Field

[0001] The present invention relates to the technical field of olefin polymerization, and in particular to a polyolefin fluidized bed reactor and a stable operation method, system, terminal and medium. Background Art

[0002] In gas-phase polymerization processes, to prevent the accumulation of large-sized products or agglomerates within the fluidized bed reactor, the reactor discharge pipeline discharges polymer particles intermittently. However, intermittent discharge, characterized by short durations, large discharge volumes, and extremely high pressure differentials, creates a plunger-like impact on the system, causing severe vibration in the pipeline and connected steel structures, frequent bracket loosening and breakage, and pneumatic valves operating far beyond their designed lifespans. Furthermore, significantly increasing the frequency of intermittent discharge can cause pipeline fatigue, significantly reducing their designed lifespans.

[0003] In addition to affecting the equipment, intermittent discharge can also affect normal production operations, causing drastic fluctuations in temperature and pressure within the fluidized bed reactor, deteriorating fluidization quality. Drastic pressure fluctuations can even lead to agglomeration, which in turn affects fluidization quality and may even necessitate shutdown. Therefore, optimizing the discharge method to ensure long-term stable operation of the reactor is of great significance.

[0004] After searching, we found:

[0005] Chinese invention patent CN1155623C discloses a method and apparatus for discharging polymer from a polymerization reactor. The discharge of polymer can achieve truly continuous discharge without any interference with the polymerization reaction. The discharge rate of the polymer can be flexibly adjusted according to the polymerization reaction, and if the production capacity of the reactor increases, it can also be easily increased proportionally. However, the fluctuations in temperature and pressure during discharge have not been studied. Chinese utility model patent CN208356730U provides a continuous feed-in and feed-out type, intermittent type fluidized bed reaction experimental system. The system has strong scalability and a wide range of applications, and additional configuration components such as a feed device, a sampling system, and an air intake device enable combined optimization of the system process. In addition, the control system can realize real-time collection and control of data such as gas volume, pressure, temperature, bed height, as well as the distribution of concentrated and dilute phases, and feed amount, breaking through the constraints of traditional reactor heating capacity. However, the patent does not provide detailed information on the control of pressure and temperature during the discharge process.

[0006] Chinese utility model patent CN88211364U describes a batch-type polypropylene gas-phase fluidized bed dechlorination reactor. This fluidized bed reactor features a special gas distribution ring to accommodate the sudden pressure changes and material impact during the batch process. A solid-phase discharge line is located at the bottom of the attached stirring device, accommodating the full discharge requirements of the batch process and providing a high processing capacity. However, this device only uses the special gas distribution ring to withstand the sudden pressure changes and material impact during batch discharge, and does not actually address the problem at its source.

[0007] In summary, the existing technology still does not truly solve the problem of stable operation of gas phase fluidized bed reactor due to discharge. Currently, no description or report of similar technology to the present invention has been found, and similar information at home and abroad has not been collected. Summary of the Invention

[0008] In view of the above-mentioned deficiencies in the prior art, the present invention provides a polyolefin fluidized bed reactor and a stable operation method, system, terminal and medium.

[0009] According to one aspect of the present invention, a method for stable operation of a polyolefin fluidized bed reactor is provided. According to control conditions, a continuous discharge line is added to the middle of the fluidized bed reactor. The ratio of the mass flow rate m2 of the intermittent discharge line to the mass flow rate m1 of the continuous discharge line is dynamically controlled according to characteristic parameters of a detection signal, thereby maintaining stable operation of the fluidized bed.

[0010] in:

[0011] The detection signal is: bed temperature, bed pressure drop or bed acoustic wave signal;

[0012] The characteristic parameters are: relative standard deviation σ, attractor comparison method S value or failure coefficient C H ;

[0013] The control conditions include:

[0014] When the characteristic parameter is less than or equal to the set criterion threshold, the fluidized bed is considered to be operating stably and no regulation is performed;

[0015] When the characteristic parameter is greater than the set judgment threshold, regulation is performed. At this time, a continuous discharge pipeline m1 is added, and the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline is reduced to 0-1, so that the fluidized bed returns to stability.

[0016] Preferably, when the characteristic parameter is the relative standard deviation, the set criterion threshold is 5%.

[0017] Preferably, when the characteristic parameter is the attractor comparison method S value, the set criterion threshold is 3.

[0018] Preferably, the characteristic parameter is the failure coefficient C H When , the set criterion threshold is 0.2.

[0019] Preferably, the continuous discharge pipeline is set at 0.05 to 0.6 times the bed height from the bottom end of the straight section of the fluidized bed, and the intermittent discharge pipeline is set at 0 to 0.3 times the bed height from the bottom end of the straight section of the fluidized bed.

[0020] Preferably, at least one continuous discharge pipeline is provided, and at least one intermittent discharge pipeline is provided.

[0021] Preferably, when there are multiple continuous discharge pipelines, the interfaces of the multiple continuous discharge pipelines are evenly arranged along the circumference of the fluidized bed reactor.

[0022] Preferably, the fault parameter C H It is used to monitor and characterize the generation of agglomeration and to provide real-time early warning for irreversible fluidization of the fluidized bed; wherein, the fault parameter C H Defined as:

[0023]

[0024] Where C H is the fault coefficient represented by the characteristic signal correlation dimension, C H，a Represents the real-time failure coefficient of the fluidized bed during operation, C H，0 Represents the chaotic parameters when the fluidized bed is operating normally; when a fault occurs in the fluidized bed, the fault coefficient will increase sharply.

[0025] According to another aspect of the present invention, a stable operation system for a polyolefin fluidized bed reactor is provided, comprising:

[0026] Continuous discharge control module, which adds a continuous discharge pipeline in the middle of the fluidized bed reactor according to the control conditions;

[0027] a flow regulation module, which dynamically regulates the mass flow rate m2 of the intermittent discharge pipeline and the mass flow rate m1 of the continuous discharge pipeline according to the characteristic parameters of the detection signal, and further adjusts the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline, thereby maintaining the stable operation of the fluidized bed;

[0028] in:

[0029] The detection signal is: bed temperature, bed pressure drop or bed acoustic wave signal;

[0030] The characteristic parameters are: relative standard deviation σ, attractor comparison method S value or failure coefficient C H ;

[0031] The control conditions include:

[0032] When the characteristic parameter is less than or equal to the set criterion threshold, the fluidized bed is considered to be operating stably and no regulation is performed;

[0033] When the characteristic parameter is greater than the set judgment threshold, regulation is performed. At this time, a continuous discharge pipeline m1 is added, and the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline is reduced to 0-1, so that the fluidized bed returns to stability.

[0034] According to a third aspect of the present invention, a polyolefin fluidized bed reactor is provided, which uses any of the above-mentioned methods for stabilizing the operation of a polyolefin fluidized bed reactor to maintain stable operation of the fluidized bed.

[0035] According to a fourth aspect of the present invention, a terminal is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor may be configured to execute any one of the methods described above when executing the program.

[0036] According to a fifth aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, it can be used to perform any of the methods described above.

[0037] Due to the adoption of the above technical solution, the present invention has at least one of the following beneficial effects compared with the prior art:

[0038] The polyolefin fluidized bed reactor and stable operation method, system, terminal and medium provided by the present invention add a continuous discharge device in the middle of the fluidized bed. By dynamically adjusting the intermittent / continuous discharge ratio online, the impact of intermittent discharge on the device system is significantly reduced, the operating life of the device is effectively extended, the deterioration of fluidization quality and the accumulation of reactor agglomerates are avoided, and the long-term stable operation of the reactor is guaranteed.

[0039] The polyolefin fluidized bed reactor and stable operation method, system, terminal and medium provided by the present invention realize stable operation of the fluidized bed at a high material level and improve production capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0041] Figure 1 1 is a flowchart of a method for stable operation of a polyolefin fluidized bed reactor according to one embodiment of the present invention.

[0042] Figure 2 This is a schematic diagram of a gas phase polyolefin fluidized bed discharge method.

[0043] Figure 3 This is a pressure signal response curve diagram of using a fault model to control fluidization quality in a preferred embodiment of the present invention.

[0044] Figure 4 This is a temperature response curve diagram of using a fault model to control fluidization quality in a preferred embodiment of the present invention.

[0045] Figure 5 This is a graph showing the acoustic signal response for controlling fluidization quality using a fault model in a preferred embodiment of the present invention; wherein (a) is when the fault coefficient exceeds a set threshold, and (b) is when the fault coefficient is less than the set threshold.

[0046] Figure 6 Schematic diagram of the component modules of the method for stable operation of a polyolefin fluidized bed reactor in one embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process. It should be noted that those skilled in the art may make various modifications and improvements without departing from the scope of the present invention, and these modifications and improvements fall within the scope of protection of the present invention.

[0048] Figure 1 This is a flowchart of a method for stable operation of a polyolefin fluidized bed reactor provided by one embodiment of the present invention.

[0049] like Figure 1 As shown, the method for stable operation of a polyolefin fluidized bed reactor provided in this embodiment may include the following steps:

[0050] S100, adding a continuous discharge pipeline in the middle of the fluidized bed reactor according to the control conditions;

[0051] S200, dynamically adjusting the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline according to the characteristic parameters of the detection signal, thereby maintaining stable operation of the fluidized bed;

[0052] in:

[0053] The detection signal is: bed temperature, bed pressure drop or bed acoustic wave signal;

[0054] The characteristic parameters are: relative standard deviation σ, attractor comparison method S value or failure coefficient C H ;

[0055] The control conditions include:

[0056] When the characteristic parameter is less than or equal to the set criterion threshold, the fluidized bed is considered to be operating stably and no regulation is performed;

[0057] When the characteristic parameter is greater than the set judgment threshold, regulation is performed. At this time, a continuous discharge pipeline m1 is added, and the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline is reduced to 0-1, so that the fluidized bed returns to stability.

[0058] In a specific application example of this embodiment, the detection signal is the bed temperature or the bed pressure drop or the bed acoustic wave signal; the characteristic parameter is the relative standard deviation σ or the attractor comparison method S value or the fault coefficient C H When the characteristic parameter is less than or equal to the threshold, the fluidized bed is considered stable. At this point, m2 / m1 = 0-1, and no regulation is performed. When the characteristic parameter is greater than the threshold, a continuous discharge line m1 is added, reducing m2 / m1 to 0-1, thereby restoring stability to the fluidized bed.

[0059] In a specific application example of this embodiment, when the characteristic parameter is the relative standard deviation, the judgment threshold is 5%; when the characteristic parameter is the attractor comparison method S value, the judgment threshold is 3; when the characteristic parameter is the fault coefficient C H When , the criterion threshold is 0.2.

[0060] The failure coefficient C H A brief introduction to the S value of the attractor comparison method is given.

[0061] In the process of signal extraction and analysis in the fluidized bed, chaotic parameters are introduced to monitor and characterize the generation of agglomeration, which is used to provide real-time early warning of irreversible fluidization of the fluidized bed. In order to facilitate the application of the changes in chaotic parameters during the agglomeration process, the fault parameter C is defined. H for:

[0062]

[0063] Where C H is the fault coefficient represented by the characteristic signal correlation dimension, C H，a represents the real-time failure coefficient (correlation dimension) of the fluidized bed during operation, C H，0 Represents the chaotic parameters of the fluidized bed during normal operation. When a fault (such as agglomeration) occurs in the fluidized bed, the fault coefficient will increase sharply. Therefore, in the embodiment of the present invention, the current state of the system will be judged by setting a threshold. When the fault coefficient C H When the threshold is exceeded, it can be determined that a fault has occurred in the current system, and corresponding measures can be taken to prevent the system from facing a worse situation.

[0064] The attractor comparison method falls under the category of chaos analysis. Its core is to statistically compare the differences between two attractors reconstructed in multidimensional space from a reference time series (normal operating conditions) and an evaluation time series (operating conditions), ultimately determining whether the two time series signals are generated by the same mechanism. Specifically, the concept of multidimensional space in chaos theory is used to statistically calculate the distance between the two attractors in m-dimensional space. The final result is then judged using hypothesis testing and the eigenvalue S: when S > 3, there is a 95% probability that the current operating state is different from the reference state, indicating that agglomeration may have occurred within the reactor. When S < 3, the current fluid dynamics behavior is the same as under normal conditions, indicating that the reactor is operating normally.

[0065] In a specific application example of this embodiment, the continuous discharge pipeline of the fluidized bed reactor is set at 0.05 to 0.6 times the bed height from the bottom end of the straight cylinder section, and the intermittent discharge pipeline is set at 0 to 0.3 times the bed height from the bottom end of the straight cylinder section.

[0066] In a specific application example of this embodiment, at least one continuous discharge pipeline is provided, and at least one intermittent discharge pipeline is provided. When multiple continuous discharge pipelines are provided, they should be evenly arranged along the circumference of the fluidized bed reactor.

[0067] In a specific application example of this embodiment, the relationship between the ratio m2 / m1 of the intermittent discharge mass flow rate m2 to the continuous discharge mass flow rate m1 and the characteristic parameter is established in the form of f(m2 / m1)=g(characteristic parameter) (m2 / m1 is a function of the characteristic parameter). By correlating the polynomial, the simplified model form is (G s =cm 3 +dm 2 +em+f), where m represents the flow ratio m2 / m1, G s Indicates characteristic parameters. When different characteristic parameters (such as relative standard deviation σ, attractor comparison method S value, failure coefficient C H ), the values ​​of c, d, e, and f are fitted. c, d, e, and f can also be functions of relevant parameters at the discharge pipeline interface. By varying the operating gas velocity and flow rate, the model parameter values ​​for different characteristic signals can be calibrated. Based on the critical thresholds of the characteristic parameters, the critical value of the flow ratio m can be solved, thereby determining the direction of the current decision (operation).

[0068] The polyolefin fluidized bed reactor and stable operation method provided by the above embodiments of the present invention are aimed at the problem that the single intermittent discharging mode of the existing gas-phase fluidized bed reactor in the gas-phase polyolefin production process will cause unstable operation of the fluidized bed. A continuous discharging pipeline is added in the middle position of the existing fluidized bed. By means of intermittent discharging and continuous discharging linkage regulation, according to the relative size of the characteristic parameters of the detection signal and the judgment threshold, the intermittent / continuous discharging ratio m2 / m1 is dynamically adjusted online to avoid deterioration of fluidization quality and accumulation of reactor agglomerates, effectively improve the fluidization quality in the fluidized bed, and ensure long-term stable operation of the reactor.

[0069] The stable operation method of the polyolefin fluidized bed reactor provided by the above embodiment of the present invention will be further described below with reference to specific application examples and drawings, but the protection scope of the present invention is not limited thereto.

[0070] Example 1

[0071] The fluidized bed discharging method used in Example 1 is as follows Figure 2 As shown, an intermittent discharge pipeline and a continuous discharge pipeline are respectively set on the fluidized bed reactor. The continuous discharge pipeline is set at 0.5 times the bed height from the bottom end of the straight cylinder section, and the intermittent discharge pipeline is set at 0.2 times the bed height from the bottom end of the straight cylinder section.

[0072] During the normal operation of the fluidized bed reactor, the pressure pulsation is obtained through online pressure detection, which is used to reflect the fluidization state and obtain the fault coefficient of the signal in real time. Based on the fault coefficient criterion, the intermittent / continuous discharge ratio m2 / m1 is adjusted.

[0073] according to Figure 3 The pressure pulsation situation reflected is that within 0 to 12 hours, the intermittent / continuous discharge ratio is m2 / m1=2, and the failure coefficient C H Exceeding the threshold of 0.2 indicates that the fluidization state in the bed is unstable and agglomeration increases. Therefore, the continuous discharge m1 set in the middle of the bed is increased to reduce m2 / m1 to 0.5, and the failure coefficient C H When the pressure drops below the threshold of 0.2, the pressure fluctuation decreases, the agglomeration phenomenon is significantly reduced, and the fluidization state of the bed gradually returns to stability.

[0074] Example 2

[0075] In Example 2, two continuous discharge pipelines and two intermittent discharge pipelines are respectively set on the fluidized bed reactor. The two continuous discharge pipelines are set at 0.5 times the bed height from the bottom end of the straight cylinder section and are symmetrically arranged on both sides of the fluidized bed reactor; the two intermittent discharge pipelines are set at 0.2 times the bed height from the bottom end of the straight cylinder section and are also symmetrically arranged on both sides of the fluidized bed reactor.

[0076] During the normal operation of the fluidized bed reactor, the temperature pulsation is obtained by online temperature detection, which is used to reflect the fluidization state and obtain the fault coefficient of the signal in real time. Based on the fault coefficient criterion, the intermittent / continuous discharge ratio m2 / m1 is adjusted.

[0077] Figure 4 It reflects the temperature response of the fluidized bed reactor during the control process. According to the figure, within 0 to 12 hours, the intermittent / continuous discharge ratio is m2 / m1=2, and the failure coefficient C H Exceeding the threshold of 0.2 indicates that the fluidization state in the bed is unstable and agglomeration increases. Therefore, the continuous discharge m1 set in the middle of the bed is increased to reduce m2 / m1 to 0.5, and the failure coefficient C H When the temperature drops below the threshold of 0.2, the temperature fluctuation decreases, the agglomeration phenomenon is significantly reduced, and the fluidization state of the bed gradually returns to stability.

[0078] Example 3

[0079] In Example 3, two continuous discharge pipelines and one intermittent discharge pipeline are respectively set on the fluidized bed reactor. The two continuous discharge pipelines are set at 0.4 times the bed height from the bottom end of the straight cylinder section and are symmetrically arranged on both sides of the fluidized bed reactor; the intermittent discharge pipeline is set at 0.1 times the bed height from the bottom end of the straight cylinder section.

[0080] Figure 5 Figures (a) and (b) reflect the acoustic signal response during the fluidized bed reactor control process. Within 0 to 12 hours, the intermittent / continuous discharge ratio m2 / m1 = 2, and the failure coefficient exceeds the threshold of 0.2. At this time, the discharge port agglomerates increase, the bed fluidization state is unstable, and the acoustic signal amplitude is small. Therefore, the side discharge flow rate m1 is increased to reduce m2 / m1 to 0.5, and the failure coefficient C H When it is reduced to below the threshold value of 0.2, the amplitude of the acoustic signal increases and the agglomeration at the discharge port is effectively reduced, indicating that the fluidization quality of the gas-phase fluidized bed reactor has been effectively improved and regulated.

[0081] The fluidized bed side-line continuous discharge process set up in the above three examples can reduce the intermittent discharge volume and frequency, effectively alleviating the extreme pressure difference caused by large-scale intermittent discharge, as well as the violent vibration of pipelines and connected steel structures, and reducing the loosening of brackets. In addition, the frequency of use of each pneumatic valve has been reduced from approximately 200,000 times per year to 180,000 times, extending the life of the device by 20%. Through the regulation of side-line discharge, particle agglomeration and deterioration of fluidization quality are prevented, and the long-term operation of the device's continuous discharge system is achieved, ensuring the normal discharge and transportation of gas-phase reactor products. When the gas-phase fluidized bed material level is increased from 16m to 18.5m, the production capacity increases by 20% while maintaining stable operation.

[0082] Figure 6A schematic diagram of the component modules of a stable operation system for a polyolefin fluidized bed reactor provided in one embodiment of the present invention.

[0083] like Figure 6 As shown, the stable operation system of the polyolefin fluidized bed reactor provided in this embodiment may include the following modules:

[0084] Continuous discharge control module, which adds a continuous discharge pipeline in the middle of the fluidized bed reactor according to the control conditions;

[0085] a flow regulation module, which dynamically regulates the mass flow rate m2 of the intermittent discharge pipeline and the mass flow rate m1 of the continuous discharge pipeline according to the characteristic parameters of the detection signal, and further adjusts the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline, thereby maintaining the stable operation of the fluidized bed;

[0086] in:

[0087] The detection signal is: bed temperature, bed pressure drop or bed acoustic wave signal;

[0088] The characteristic parameters are: relative standard deviation σ, attractor comparison method S value or failure coefficient C H ;

[0089] The control conditions include:

[0090] When the characteristic parameter is less than or equal to the set criterion threshold, the fluidized bed is considered to be operating stably and no regulation is performed;

[0091] When the characteristic parameter is greater than the set judgment threshold, regulation is performed. At this time, a continuous discharge pipeline m1 is added, and the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline is reduced to 0-1, so that the fluidized bed returns to stability.

[0092] It should be noted that the steps in the method provided by the present invention can be implemented using corresponding modules, devices, units, etc. in the system. Those skilled in the art can refer to the technical solution of the method to implement the composition of the system, that is, the embodiments in the method can be understood as preferred examples of constructing the system, which will not be elaborated here.

[0093] An embodiment of the present invention provides a polyolefin fluidized bed reactor, which uses the method for stabilizing the operation of a polyolefin fluidized bed reactor according to any one of the above embodiments of the present invention to maintain stable operation of the fluidized bed.

[0094] An embodiment of the present invention provides a terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it can be used to execute any one of the methods in the above embodiments of the present invention.

[0095] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, it can be used to execute any one of the methods in the above embodiments of the present invention.

[0096] Optionally, the memory is used to store programs; the memory may include volatile memory (English: volatile memory), such as random-access memory (English: random-access memory, abbreviated: RAM), such as static random-access memory (English: static random-access memory, abbreviated: SRAM), double data rate synchronous dynamic random access memory (English: Double Data Rate Synchronous Dynamic Random Access Memory, abbreviated: DDR SDRAM), etc.; the memory may also include non-volatile memory (English: non-volatile memory), such as flash memory (English: flash memory). The memory is used to store computer programs (such as applications, functional modules, etc. that implement the above-mentioned methods), computer instructions, etc., and the above-mentioned computer programs, computer instructions, etc. can be partitioned and stored in one or more memories. In addition, the above-mentioned computer programs, computer instructions, data, etc. can be called by the processor.

[0097] The aforementioned computer programs, computer instructions, etc. may be partitioned and stored in one or more memories, and the aforementioned computer programs, computer instructions, data, etc. may be called by a processor.

[0098] The processor is configured to execute the computer program stored in the memory to implement the various steps of the method involved in the above embodiment. For details, please refer to the relevant description in the above method embodiment.

[0099] The processor and memory can be independent structures or integrated structures. When the processor and memory are independent structures, the memory and processor can be coupled via a bus.

[0100] The polyolefin fluidized bed reactor and stable operation method, system, terminal and medium provided by the above embodiments of the present invention address the problem that intermittent discharging of polymer particles can easily cause abnormal fluidization state and even cause shutdown. In the gas phase polyolefin production process, a continuous discharge pipeline is added in the middle of the fluidized bed. By dynamically adjusting the intermittent / continuous discharge ratio online, not only the deterioration of fluidization quality and reactor agglomeration accumulation are avoided, but also high material level operation can be performed, thereby improving production capacity and ensuring long-term stable operation of the reactor.

[0101] Matters not mentioned in the above embodiments of the present invention are well known in the art.

[0102] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various variations or modifications within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A method for stable operation of a polyolefin fluidized bed reactor, characterized in that: A continuous discharge pipeline is added in the middle of the fluidized bed reactor, and the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline is dynamically adjusted according to the characteristic parameters of the detection signal, thereby maintaining the stable operation of the fluidized bed; in: The detection signal is: bed temperature, bed pressure drop or bed acoustic wave signal; The characteristic parameters are: relative standard deviation σ, attractor comparison method S value or failure coefficient C H ; The control conditions include: When the characteristic parameter is less than or equal to the set criterion threshold, the fluidized bed is considered to be operating stably and no regulation is performed; When the characteristic parameter is greater than the set judgment threshold, regulation is performed to reduce the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline to 0-1, thereby restoring stability of the fluidized bed.

2. The method for stable operation of a polyolefin fluidized bed reactor according to claim 1, characterized in that: Also includes any one or more of the following: When the characteristic parameter is the relative standard deviation, the set criterion threshold is 5%; When the characteristic parameter is the attractor comparison method S value, the set criterion threshold is 3; The characteristic parameter is the failure coefficient C H When , the set criterion threshold is 0.

2.

3. The method for stable operation of a polyolefin fluidized bed reactor according to claim 1, characterized in that: The intermittent discharge pipeline is arranged at a distance of 0 to 0.3 times the bed height from the bottom end of the straight cylindrical section of the fluidized bed.

4. The method for stable operation of a polyolefin fluidized bed reactor according to claim 1, characterized in that: At least one continuous discharge pipeline is provided, and at least one intermittent discharge pipeline is provided.

5. The method for stable operation of a polyolefin fluidized bed reactor according to claim 4, characterized in that: When there are multiple continuous discharge pipelines, the interfaces of the multiple continuous discharge pipelines are evenly arranged along the circumference of the fluidized bed reactor.

6. The method for stable operation of a polyolefin fluidized bed reactor according to claim 1, characterized in that: The failure coefficient C H Used to monitor and characterize the generation of agglomeration and provide real-time early warning of irreversible fluidization of the fluidized bed; wherein the failure coefficient C H Defined as: Where C H is the fault coefficient represented by the characteristic signal correlation dimension, C H,a represents the real-time chaotic parameter of the fluidized bed during operation, C H,0 Represents the chaotic parameters when the fluidized bed is operating normally; when a fault occurs in the fluidized bed, the fault coefficient will increase sharply.

7. A polyolefin fluidized bed reactor stable operation system, characterized in that: include: Continuous discharge control module, which adds a continuous discharge pipeline in the middle of the fluidized bed reactor; a flow regulation module, which dynamically regulates the mass flow rate m2 of the intermittent discharge pipeline and the mass flow rate m1 of the continuous discharge pipeline according to the characteristic parameters of the detection signal, and further adjusts the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline, thereby maintaining the stable operation of the fluidized bed; in: The detection signal is: bed temperature, bed pressure drop or bed acoustic wave signal; The characteristic parameters are: relative standard deviation σ, attractor comparison method S value or failure coefficient C H ; The control conditions include: When the characteristic parameter is less than or equal to the set judgment threshold, the fluidized bed is considered to be running stably and no regulation is performed; When the characteristic parameter is greater than the set judgment threshold, regulation is performed to reduce the ratio of the mass flow rate m2 of the intermittent discharge pipeline to the mass flow rate m1 of the continuous discharge pipeline to 0-1, thereby restoring stability of the fluidized bed.

8. A polyolefin fluidized bed reactor, characterized in that: The stable operation method of a polyolefin fluidized bed reactor according to any one of claims 1 to 6 is adopted to maintain the stable operation of the fluidized bed.

9. A terminal comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, it can be used to perform the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, it can be used to perform the method according to any one of claims 1 to 6.

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