Dilution ratio regulation and control method and device for cracking device and program product

Abstract

The invention discloses a dilution ratio regulation and control method and device of a cracking device and a program product. The method comprises the steps that the feeding flow and the actual steam flow of each reaction channel in each hearth are measured; calculating a steam target flow according to the feeding flow and a preset target dilution ratio; distributing steam demand flow for each reaction channel according to the steam target flow; and the valve opening degree of each reaction channel is adjusted according to the actual steam flow and the required steam flow. According to the method provided by the invention, each reaction channel can be respectively measured and regulated, so that the dilution ratio of the feeding flow to the dilution steam flow in the cracking device can be automatically, stably and accurately controlled, and the product consistency is improved while the waste of the dilution steam is avoided.

Description

Technical Field

[0001] This invention relates to the technical field of pyrolysis unit control technology, and in particular to a method, apparatus and procedure for controlling the dilution ratio of a pyrolysis unit. Background Technology

[0002] In the chemical industry, especially in ethylene production, cracking units play a crucial role. These units typically consist of multiple furnaces, each with multiple parallel reaction channels. During ethylene cracking, the mixing ratio of feedstock and dilution steam has a decisive impact on reaction efficiency and product quality. However, due to differences in feed rates in each furnace and real-time fluctuations in feed rates within the same furnace, maintaining a precise mixing ratio of feedstock and dilution steam becomes extremely complex.

[0003] Traditionally, dilution steam flow measurement relies on physical instruments, which can encounter various anomalies during operation, leading to inaccurate data. When a dilution steam flow meter malfunctions, the ratio of feedstock to dilution steam (dilution ratio) can fluctuate significantly, affecting not only the product distribution of the cracking system but also potentially negatively impacting the quality and efficiency of downstream products. Furthermore, existing methods for manually setting the dilution steam flow often require over-setting to ensure reaction stability, undoubtedly wasting steam resources.

[0004] In existing technologies, although there have been various attempts to control the dilution ratio, these methods often rely on the operator's experience. In the case of multiple furnaces in the pyrolysis unit and multiple reaction channels in the furnaces reacting simultaneously, the dilution ratio control is difficult to adapt to real-time changes in the feed rate, resulting in an unsatisfactory control effect and difficulty in meeting the need for stable control.

[0005] Therefore, there is an urgent need to develop a method that can automatically, smoothly and accurately control the feed rate and dilution ratio of dilution steam in a pyrolysis unit. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies that cannot automatically, stably, and accurately control the dilution ratio of raw materials and dilution steam in a pyrolysis unit. This invention provides a method, apparatus, and program for controlling the dilution ratio of a pyrolysis unit. By measuring and controlling the steam flow rate of each reaction channel in each furnace, the pyrolysis unit can better adapt to changes in the feed rate and dynamically control the steam flow rate of each reaction channel. This achieves automatic, stable, and accurate maintenance of the mixing ratio of raw materials and steam in the pyrolysis unit as the target dilution ratio, thereby ensuring stable product quality.

[0007] The present invention provides a method for controlling the dilution ratio of a pyrolysis device, comprising:

[0008] The feed flow rate and the actual steam flow rate in each reaction channel of each furnace were measured.

[0009] The target steam flow rate is calculated using the feed flow rate and the preset target dilution ratio;

[0010] The required steam flow rate is allocated to each of the reaction channels according to the target steam flow rate.

[0011] Adjust the valve opening of each reaction channel according to the actual steam flow rate and the steam demand flow rate.

[0012] In one of the alternative technical solutions, before measuring the feed flow rate and the actual steam flow rate in each reaction channel of each furnace, the method further includes:

[0013] Based on the steam flow soft measurement model, a steam flow soft measurement instrument is established for each reaction channel in each furnace.

[0014] The steam flow rate of each reaction channel is measured using the aforementioned steam flow rate soft measurement instrument;

[0015] The measured steam flow rate of each of the aforementioned reaction channels is taken as the actual steam flow rate.

[0016] In one of the alternative technical solutions, the steam flow soft measurement instrument based on the steam flow soft measurement model is established for each reaction channel in each furnace, specifically including:

[0017] A steam flow measurement model is established based on steam characteristics. The steam flow measurement model calculates the steam flow rate of the reaction channel based on the steam flow area, expandability coefficient, steam flow coefficient, steam pressure difference before and after the valve, and steam density.

[0018] After constantizing the characteristic parameters related to steam in the steam flow measurement model, a soft measurement constant is obtained, and a soft measurement model of steam flow is generated. The soft measurement model of steam flow calculates the soft measurement flow of steam through comprehensive coefficients, valve position data, pressure difference correction coefficients, steam pressure difference before and after the valve and soft measurement constants.

[0019] The steam flow soft measurement instrument is established based on the steam flow soft measurement model.

[0020] In one of the optional technical solutions, the steam flow measurement model is specifically as follows:

[0021]

[0022] Where F is the actual steam flow rate, J is the measurement coefficient, d is the steam flow area, ε is the expansion coefficient, α is the steam flow coefficient, ΔP is the pressure difference across the valve, and ρ is the steam density.

[0023] In one of the optional technical solutions, the steam flow soft measurement model is specifically as follows:

[0024]

[0025] Where M is the steam soft-measurement flow rate, c is the comprehensive coefficient, x is the valve position that can be read in real time, a is the differential pressure correction coefficient, b is the soft-measurement constant, and ΔP is the differential pressure across the valve.

[0026] In one of the alternative technical solutions, allocating the steam demand flow rate to each of the reaction channels according to the steam target flow rate specifically includes:

[0027] Each furnace is assigned a separate steam target based on the target steam flow rate and the number of furnaces.

[0028] The furnace in which the number of internal reaction channels cannot be evenly distributed among the steam unit targets is selected as the differentiated furnace.

[0029] A deviation variable is set for each reaction channel in each of the differentiated furnace chambers;

[0030] The steam demand flow rate for each reaction channel in the differentiated furnace is calculated based on the steam unit target and the deviation variable.

[0031] In one of the alternative technical solutions, adjusting the valve opening of each reaction channel according to the actual steam flow rate and the steam demand flow rate specifically includes:

[0032] Based on the actual steam flow rate and the required steam flow rate, the steam adjustment amount for each reaction channel is calculated;

[0033] Based on the current valve position of the valve in each reaction channel and the steam adjustment amount, the target control valve position corresponding to each reaction channel is calculated;

[0034] The valves in each of the reaction channels are controlled to adjust their positions accordingly.

[0035] The present invention provides a computer device, including a memory, a processor, and a computer program on the memory, wherein the processor executes the computer program to implement the steps of the dilution ratio control method of any of the aforementioned pyrolysis devices.

[0036] The present invention provides a computer-readable storage medium storing a computer program / instruction thereon, which, when executed by a processor, implements the steps of the dilution ratio control method of any of the aforementioned pyrolysis devices.

[0037] The present invention provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the dilution ratio control method of any of the aforementioned pyrolysis devices.

[0038] The above technical solution has the following beneficial effects:

[0039] The dilution ratio control method for the pyrolysis device provided by the present invention measures the actual steam flow rate of each reaction channel in each furnace, calculates the steam demand flow rate of the pyrolysis device based on the target dilution ratio of the pyrolysis device, and allocates the target steam flow rate to each reaction channel in each furnace, thereby enabling individual control of the steam flow rate of each reaction channel.

[0040] This invention significantly improves control precision by automating calculations and execution, eliminating reliance on manual control. Furthermore, it abandons the traditional method of setting excessive steam, ensuring that the ratio of overall feed flow to actual steam flow in the pyrolysis unit remains at the target dilution ratio even when the feed flow fluctuates, thus adapting to feed flow fluctuations, maintaining a stable dilution ratio within the pyrolysis unit, and consequently ensuring consistent product quality. Attached Figure Description

[0041] The disclosure of this invention will become more readily understood by referring to the accompanying drawings. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings:

[0042] Figure 1 A flowchart illustrating the dilution ratio control method of a pyrolysis apparatus according to an embodiment of the present invention;

[0043] Figure 2 A flowchart illustrating the dilution ratio control method of a pyrolysis apparatus according to an embodiment of the present invention;

[0044] Figure 3 A flowchart illustrating the dilution ratio control method of a pyrolysis apparatus according to an embodiment of the present invention;

[0045] Figure 4 A flowchart illustrating the dilution ratio control method of a pyrolysis apparatus according to an embodiment of the present invention;

[0046] Figure 5 A flowchart illustrating the dilution ratio control method of a pyrolysis apparatus according to an embodiment of the present invention;

[0047] Figure 6 This is a schematic diagram of the structure of a computer device according to an embodiment of the present invention. Detailed Implementation

[0048] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0049] It should be noted that the pyrolysis device described in the technical solution of this invention specifically refers to a pyrolysis device composed of multiple furnace chambers, each furnace chamber having multiple parallel reaction channels, each of which is undergoing pyrolysis to produce products such as ethylene. During ethylene pyrolysis, the mixing ratio of feedstock and dilution steam has a significant impact on the efficiency of the pyrolysis reaction and the quality of the pyrolysis products. Therefore, the technical solution of this invention mainly targets pyrolysis devices or pyrolysis furnaces with multiple furnace chambers and multiple reaction channels within each furnace chamber. When the feedstock flow rate changes, the flow rate of dilution steam in each reaction channel is automatically measured, calculated, and automatically adjusted, and the steam flow rate of each reaction channel is distributed to maintain the ratio of feedstock to dilution steam in the pyrolysis device at the target dilution ratio required for the pyrolysis reaction. All steam mentioned below refers to dilution steam, and feed flow rate refers to the flow rate of feedstock entering the pyrolysis device.

[0050] like Figure 1 The figure shows a method for controlling the dilution ratio of a pyrolysis device according to an embodiment of the present invention, which mainly includes the following steps:

[0051] Step S101: Measure the feed flow rate and the actual steam flow rate of each reaction channel in each furnace.

[0052] Specifically, by installing measuring components in each reaction channel of each furnace in the pyrolysis unit, the actual steam flow rate in each reaction channel can be measured in real time. The measuring components include at least a flow sensor for measuring steam flow rate and a flow sensor for measuring feed flow rate. By measuring the feed flow rate and actual steam flow rate in each reaction channel of each furnace in real time using high-precision flow sensors, accurate basic data can be provided for subsequent dilution ratio control.

[0053] Preferably, a soft-sensor method can be used to measure the soft-sensor flow rate of steam, and this soft-sensor flow rate can be used as the actual steam flow rate. In pyrolysis units, it is difficult to accurately measure all characteristics of dilution steam. In this case, soft-sensor steam can be used, primarily through mechanistic modeling or experimental modeling, or a combination of both, to establish a soft-sensor model for the soft-sensor steam flow rate. Here, soft-sensor steam refers to using computer technology to measure important variables of dilution steam that are difficult or temporarily unmeasurable in pyrolysis units, such as difficult-to-measure steam characteristic parameters. Other easily measurable variables are selected, or characteristic constants are established to form a mathematical relationship for inference or estimation, thereby achieving software-based measurement instead of hardware-based measurement.

[0054] Step S102: Calculate the target steam flow rate using the feed flow rate and the preset target dilution ratio.

[0055] This step primarily involves calculating the target steam flow rate required for the entire pyrolysis unit reaction based on the measured overall feed flow rate and the preset target dilution ratio. The calculation of the target steam flow rate through a proportional relationship ensures that the ratio of the target steam flow rate to the feed flow rate is within the dilution ratio range required for the reaction. The target dilution ratio is generally determined by the mixing ratio of the reaction products to the required feed and dilution steam during the pyrolysis reaction. Therefore, this target dilution ratio can be preset by the operator before the pyrolysis reaction begins, or the optimal dilution ratio can be selected from a database based on the pyrolysis products. The allowable fluctuation range of the target dilution ratio, maintained by the feed flow rate and actual steam flow rate of the pyrolysis unit within this range, indicates that the pyrolysis unit is maintaining the target dilution ratio.

[0056] Step S103: Allocate the required steam flow rate to each of the reaction channels according to the target steam flow rate.

[0057] Using the calculated target steam flow rate, the required steam flow rate is allocated to each reaction channel. This step involves the rational allocation of steam flow throughout the cracking unit to meet the specific needs of different reaction channels. The specific allocation method is determined by the operator, or a suitable steam flow allocation algorithm can be selected from existing algorithms to achieve real-time allocation of steam flow in each reaction channel within each furnace, ensuring that the overall feed flow rate and actual steam flow rate of the cracking unit are maintained at the target dilution ratio.

[0058] Step S104: Adjust the valve opening of each reaction channel according to the actual steam flow rate and the steam demand flow rate.

[0059] Each reaction channel is equipped with a valve to individually control the steam flow rate of that channel. The opening degree of each valve is adjusted according to the actual steam flow rate and the required steam flow rate in each channel, ensuring precise control of the steam flow rate in each channel and dynamically maintaining the target dilution ratio across the entire pyrolysis unit. By dynamically adjusting the steam flow rate of each reaction channel to dynamically regulate the dilution ratio of the entire pyrolysis unit, the process of steam flow rate changes is smooth, thus smoothly responding to sudden changes in feed flow rate and ensuring the continuous and stable operation of the pyrolysis reaction.

[0060] This method ensures accurate calculation of the target steam flow rate by measuring the feed flow rate and actual steam flow rate in each reaction channel of each furnace in real time, thereby improving the control precision of the pyrolysis process. By calculating and allocating the required steam flow rate for each reaction channel, this method achieves precise control of the steam flow rate, optimizes the mixing ratio of steam and feed, and helps improve pyrolysis efficiency and product quality. This method allows for valve opening adjustment according to the specific needs of each reaction channel, providing differentiated steam distribution, enhancing the system's adaptability and flexibility to meet process requirements under different operating conditions. Automated valve adjustment reduces manual operation, lowers production fluctuations and resource waste caused by improper operation, and improves the stability and economy of the production process. By precisely controlling the steam flow rate, this method helps reduce production costs while avoiding excessive steam use, meeting the environmental protection requirements of energy conservation and emission reduction.

[0061] In summary, the dilution ratio control method for the pyrolysis unit provided by this invention measures the actual steam flow rate of each reaction channel in each furnace, calculates the steam demand flow rate of the pyrolysis unit based on the target dilution ratio, and allocates the target steam flow rate to each reaction channel in each furnace, thereby achieving individual control of the steam flow rate for each reaction channel. This invention, through automated calculation and execution, eliminates reliance on manual control, significantly improving control accuracy. Furthermore, this invention abandons the traditional method of setting excess steam, ensuring that the ratio of the overall feed flow rate to the actual steam flow rate in the pyrolysis unit maintains the target dilution ratio even when the feed flow rate fluctuates, while avoiding steam waste. This adapts to fluctuations in feed flow rate, ensures a stable dilution ratio within the pyrolysis unit, and thus ensures consistent product quality.

[0062] In one embodiment, such as Figure 2 As shown, prior to the above steps, the following steps are also included:

[0063] Step S201: Based on the steam flow soft measurement model, establish a steam flow soft measurement instrument for each reaction channel in each furnace.

[0064] Step S202: Softly measure the steam flow rate of each reaction channel using the steam flow rate soft measurement instrument.

[0065] Step S203: The measured steam soft-measurement flow rate of each of the reaction channels is taken as the actual steam flow rate.

[0066] In this embodiment, a soft measurement instrument for steam flow is established in each reaction channel to perform real-time soft measurement of the steam flow rate in the reaction channel. Since some characteristic parameters of steam are difficult to measure or have high measurement costs, and these steam characteristic parameters have little impact on the calculated actual steam flow rate, these parameters can be processed. The measurement performed after processing is the steam soft measurement. Steam soft measurement does not require accurate measurement of these characteristic parameters of steam. In this embodiment, the steam flow soft measurement instrument uses a steam flow soft measurement model as the basis for soft measurement of steam flow rate, and uses this soft measurement value as the actual steam flow rate. This can obtain the required accuracy of the actual steam flow rate while significantly reducing the difficulty of obtaining the parameters needed to measure the steam flow rate. The steam flow soft measurement instrument is a measuring instrument that only measures the dominant variable, converts variables that are difficult to measure or have little impact on the result into auxiliary variables, and then performs soft measurement of the steam flow rate as the actual steam flow rate. It is not a traditional physical instrument, but rather an instrument model without measurement delay issues.

[0067] In one embodiment, such as Figure 3 As shown, the steam flow soft measurement instrument is established for each reaction channel in each furnace based on the steam flow soft measurement model, specifically including the following steps:

[0068] Step S301: Establish a steam flow measurement model based on steam characteristics. The steam flow measurement model calculates the steam flow rate of the reaction channel based on the steam flow area, expandability coefficient, steam flow coefficient, steam pressure difference before and after the valve, and steam density.

[0069] Step S302: After constantizing the characteristic parameters related to steam in the steam flow measurement model, a soft measurement constant is obtained, and a steam flow soft measurement model is generated. The steam flow soft measurement model calculates the steam soft measurement flow rate through comprehensive coefficients, valve position data, pressure difference correction coefficients, steam pressure difference before and after the valve, and soft measurement constants.

[0070] Step S303: Establish the steam flow soft measurement instrument based on the steam flow soft measurement model.

[0071] In this embodiment, the steam flow measurement model calculates the steam flow rate in the reaction channel using the steam flow area, expandability coefficient, steam flow coefficient, steam pressure difference across the valve, and steam density. Specifically, the steam flow measurement model is as follows:

[0072]

[0073] Where F is the actual steam flow rate, J is the measurement coefficient, d is the steam flow area, ε is the expandability coefficient, α is the steam flow coefficient, ΔP is the pressure difference across the valve, and ρ is the steam density. The steam flow measurement model is a measurement model obtained through mechanistic analysis of the actual steam flow rate in the reaction channel. The measurement coefficient J is a constant for steam flow measurement calculations determined based on the internal structure of the reaction channel. Taking a common reaction channel structure as a specific calculation example, the measurement coefficient J can be selected as 0.0039 to calculate the actual steam flow rate. The steam flow measurement model also performs precise calculations by accurately measuring the steam flow area, expandability coefficient, steam flow coefficient, steam pressure difference across the valve, and steam density to accurately calculate the current actual steam flow rate in the reaction channel.

[0074] Since the steam in the reaction channel of the furnace is not actually in an ideal state, and some characteristic parameters of the steam are difficult to measure accurately or are costly to measure, this embodiment constants some characteristic parameters of the steam based on historical data of the pyrolysis unit. This means these parameters are used as auxiliary variables, with estimated values ​​used as calculated values. Furthermore, the relationship between the valve position in the reaction channel and the steam flow area (i.e., the valve orifice size) is digitized, allowing the valve position to be read in real time. This transforms the steam flow measurement model into a soft steam flow measurement model. Preferably, the soft steam flow measurement model is as follows:

[0075]

[0076] Where M is the steam soft-sensor flow rate, K is the valve position coefficient, c is the comprehensive coefficient, x is the real-time readable valve position, a is the differential pressure correction coefficient, b is the soft-sensor constant, and ΔP is the differential pressure across the valve. The valve position coefficient K is selected based on the steam flow area d and the valve size.

[0077] The specific relationship between steam flow area and valve position is as follows:

[0078] d = x-1 ;

[0079] Wherein, R is a radius coefficient related to the valve size in the reaction channel, used to convert the steam flow area. In actual calculations, the specific value of R needs to be selected according to the structure of the reaction channel, and the valve position coefficient K is calculated based on the value of the radius coefficient R. By combining the valve position coefficient K and the real-time readable valve position x, the current valve position can be digitized to facilitate valve position detection and control. In common reaction channels, the valve position coefficient can preferably be 30.3 to calculate the steam soft measurement flow rate. This invention discloses one method for steam flow soft measurement in a reaction channel. The steam flow measurement model is converted into a steam flow soft measurement model to measure the steam soft measurement flow rate. Then, the steam soft measurement flow rate with deviation within an acceptable range is taken as the actual steam flow rate in the reaction channel. This allows for the real-time measurement of the actual steam flow rate in each reaction channel in each furnace of the pyrolysis unit without significantly increasing the measurement difficulty and cost.

[0080] In one embodiment, such as Figure 4 As shown, step S103, which allocates the steam demand flow rate to each of the reaction channels according to the target steam flow rate, specifically includes the following steps:

[0081] Step S401: Assign individual steam targets to each furnace based on the target steam flow rate and the number of furnaces.

[0082] Step S402: Select the furnace where the number of internal reaction channels cannot be evenly distributed among the steam unit targets as the differentiated furnace.

[0083] Step S403: Set a deviation variable for each reaction channel in each of the differentiated furnace chambers.

[0084] Step S404: Calculate the steam demand flow rate for each reaction channel in the differentiated furnace based on the steam unit target and the deviation variable.

[0085] In this embodiment, it is assumed that there are i furnaces in total. A target steam flow rate is allocated to each furnace based on the target steam flow rate. In this case, the dilution ratio of each furnace is R. i The real-time feed rate for each furnace is FA. i The steam unit target FB for each furnace i =A i ×R i The target steam flow rate for each furnace can be calculated. To reduce the difference in steam flow rate between furnaces, thereby reducing the computational load and control difficulty, the target steam flow rate is generally the same for each furnace when the number of furnaces can evenly distribute the target steam flow rate. Differentiation is only performed when the flow rate cannot be evenly distributed, so as to achieve a dynamic balance of the dilution ratio.

[0086] In cases where the number of furnaces or reaction channels cannot evenly distribute the steam demand per unit, i.e., when a differentiated furnace needs to be selected, assuming the differentiated furnace is i and has j reaction channels, a deviation variable is set for each reaction channel to facilitate steam flow allocation. The specific calculation method for the steam demand flow rate of each reaction channel is as follows:

[0087]

[0088] Among them, DS j For the steam demand flow rate, a j Let n be the number of reaction channels in the differentiated furnace, and FB be the deviation variable. i The target steam flow rate for the differentiated furnace.

[0089] In one embodiment, such as Figure 5 As shown, step S104 involves adjusting the valve opening of each reaction channel according to the actual steam flow rate and the required steam flow rate, specifically including the following steps:

[0090] Step S501: Calculate the steam adjustment amount for each reaction channel based on the actual steam flow rate and the required steam flow rate.

[0091] Step S502: Calculate the target control valve position corresponding to each reaction channel based on the current valve position of the valve in each reaction channel and the steam adjustment amount.

[0092] Step S503: Control the valves in each of the reaction channels to adjust their respective valve positions.

[0093] In this embodiment, by adjusting the valve position of the valve in each reaction channel, the steam flow area of ​​the reaction channel is changed by changing the valve position of the invention, thereby accurately controlling the actual steam flow rate of the reaction channel, ensuring that the actual steam flow rate of each reaction channel is the steam demand flow rate, and maintaining the dilution ratio of the furnace by individually controlling the actual steam flow rate of each reaction channel.

[0094] To precisely control the specific valve position, the valve position needs to be digitized for easy reading and adjustment. In this embodiment, the valve position value is set as a percentage of the valve opening. By calculation, the valve position value corresponding to the steam demand flow rate can be determined. Changing the valve position value changes the specific location of the valve, thereby altering the steam flow area of ​​the reaction channel. Specifically, the valve position is calculated as follows:

[0095]

[0096] Where V is the target valve position, K is the valve position coefficient, DS is the target steam flow rate, and the pressure difference ΔP across the valve, the pressure difference correction coefficient a, the soft measurement constant b, and the comprehensive coefficient c are obtained from the steam flow soft measurement model. The valves in each reaction channel are controlled to adjust each valve to the target valve position, thereby ensuring that the actual steam flow rate of each reaction channel can match the feed flow rate, so that the ratio of raw material to dilution steam is maintained at the target dilution ratio.

[0097] To illustrate the above embodiments with a specific application example, taking an ethylene cracking unit as an example, when the ethylene cracking reaction is carried out, it is necessary to control the dilution ratio of the cracking unit. Assume the cracking unit has 11 furnaces, 10 of which have 4 reaction channels, and the 11th furnace has 3 reaction channels. A steam measurement model is established based on the number of furnaces and reaction channels. After processing the steam measurement model, a steam flow soft measurement model is generated. Steam flow soft measurement instruments are then established for all channels based on the steam flow soft measurement model, resulting in a total of 43 soft instruments. Then, the differential pressure correction coefficient 'a', soft measurement constant 'b', and comprehensive coefficient 'c' of the steam flow soft measurement instruments are placed on the DCS side. Data on the cracking reaction is obtained. The feed setpoint for all 11 furnaces is set to 42 t / h, and the target dilution ratios for the 11 furnaces are 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, and 0.35, respectively.

[0098] Then, steam flow is allocated to each reaction channel in each furnace. In the first 10 furnaces, the steam flow can be evenly distributed among each reaction channel, and the deviation variables are all 0, so no calculation is required. The 11th furnace has 3 reaction channels. The 11th furnace is selected as the differentiated furnace, and deviation variables a1, a2 and a3 are set for the 3 reaction channels respectively, and set to 0, 0.1 and 0 respectively.

[0099] The target steam flow rate adjustment value FB for the 11 furnaces is calculated as feed rate × target dilution ratio, which are 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, 12.6t / h, and 14.7t / h, respectively.

[0100] For the first 10 furnace chambers, the target steam flow rate for each channel is 3.15 t / h. The target steam flow rate for each channel of the 11th furnace chamber is calculated as follows:

[0101]

[0102] After calculating the steam demand flow rate for each reaction channel, the steam adjustment amount for each reaction channel is calculated based on the actual steam flow rate. Furthermore, the current valve position can be calculated in each calculation cycle based on the actual steam flow rate. The steam flow rate soft measurement model is then converted into a valve position adjustment command, and the specific value of the target valve position is calculated. The data is transmitted to the DCS side to activate the valve, which is then positioned at the target valve position. The actual steam flow rate is adjusted by changing the steam flow area, so that the ratio of raw material to dilution steam in each furnace is smoothly adjusted to the target dilution ratio.

[0103] like Figure 6 The diagram shows a hardware structure of a computer device according to the present invention, including a memory 602, a processor 601, and a computer program on the memory 602. The processor 601 executes the computer program to implement the steps of the dilution ratio control method of the pyrolysis apparatus of any of the above embodiments.

[0104] Figure 6 Take the 601 processor as an example.

[0105] The computer device may also include an input device 603 and a display device 604.

[0106] The processor 601, memory 602, input device 603 and display device 604 can be connected by a bus or other means. The figure shows an example of connection by a bus.

[0107] The memory 602, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the dilution ratio control method of the pyrolysis apparatus in the embodiments of this application, for example, Figure 1 , Figure 6 The method flow is shown. The processor 601 executes various functional applications and data processing by running non-volatile software programs, instructions, and modules stored in the memory 602, thereby realizing the dilution ratio control method of the pyrolysis device in the above embodiments.

[0108] The memory 602 may include a program storage area and a data storage area. The program storage area may store an operating system and an application program required for at least one function. The data storage area may store data created based on the use of the dilution ratio control method of the pyrolysis apparatus. Furthermore, the memory 602 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 602 may optionally include memory remotely located relative to the processor 601, and these remote memories may be connected via a network to the apparatus performing the dilution ratio control method of the pyrolysis apparatus. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0109] The input device 603 can receive user clicks and generate signal inputs related to user settings and function control of the dilution ratio control method of the pyrolysis apparatus. The display device 604 may include a display screen or other display equipment.

[0110] When one or more modules are stored in the memory 602, and are run by one or more processors 601, the dilution ratio control method of the pyrolysis device in any of the above method embodiments is executed.

[0111] When the computer device disclosed in this invention is running, it can execute all the steps of the dilution ratio control method of the above-mentioned pyrolysis device. By measuring the actual steam flow rate of each reaction channel in each furnace, and then calculating the steam demand flow rate of the pyrolysis device according to the target dilution ratio of the pyrolysis device, the target steam flow rate is allocated to each reaction channel in each furnace, so as to achieve the effect of individually controlling the steam flow rate of each reaction channel in the pyrolysis device and maintaining the pyrolysis device at the target dilution ratio.

[0112] An embodiment of the present invention provides a computer-readable storage medium storing a computer program / instructions that, when executed by a processor 601, implement all the steps of the dilution ratio control method of the pyrolysis apparatus as described above.

[0113] In the context of this disclosure, a storage medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. The storage medium can be a machine-readable signal medium or a machine-readable storage medium. Optionally, the storage medium can be a non-transitory computer-readable storage medium, such as a ROM, random access memory (RAM), compact disc ROM (CD-ROM), magnetic tape, floppy disk, and optical data storage device.

[0114] An embodiment of the present invention provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the steps of the dilution ratio control method of the pyrolysis apparatus as described above.

[0115] By running the aforementioned computer program, all steps of the dilution ratio control method for the pyrolysis unit described above can be executed. By measuring the actual steam flow rate of each reaction channel in each furnace, and then calculating the steam demand flow rate of the pyrolysis unit based on the target dilution ratio, the target steam flow rate is allocated to each reaction channel in each furnace, so as to achieve the effect of individually controlling the steam flow rate of each reaction channel in the pyrolysis unit and maintaining the pyrolysis unit at the target dilution ratio.

[0116] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method of controlling the dilution ratio of a cracking apparatus, characterized by, The method comprises the following steps: measuring the feed flow rate and the actual steam flow rate of each reaction channel in each furnace; calculating the target steam flow rate based on the feed flow rate and a preset target dilution ratio; allocating a steam demand flow rate to each reaction channel according to the target steam flow rate; adjusting the valve opening degree of each reaction channel according to the actual steam flow rate and the steam demand flow rate.

2. The method of claim 1, wherein the dilution ratio is controlled by adjusting the flow rate of the carrier gas. Before the step of measuring the feed flow rate and the actual steam flow rate of each reaction channel in each furnace, the method further comprises the following steps: establishing a steam flow rate soft measurement instrument for each reaction channel in each furnace based on a steam flow rate soft measurement model; soft measuring the steam flow rate of each reaction channel by using the steam flow rate soft measurement instrument; taking the soft measured steam flow rate of each reaction channel as the actual steam flow rate.

3. The method of claim 2, wherein the dilution ratio is controlled by adjusting the flow rate of the dilution gas. The step of establishing a steam flow rate soft measurement instrument for each reaction channel in each furnace based on a steam flow rate soft measurement model specifically comprises the following steps: establishing a steam flow measurement model according to steam characteristics, wherein the steam flow measurement model calculates the steam flow rate of a reaction channel according to the steam flow area, the expandable coefficient, the steam flow coefficient, the steam pressure difference before and after the valve and the steam density; obtaining a soft measurement constant by treating the steam-related characteristic parameters in the steam flow measurement model as constants, generating a steam flow soft measurement model, and calculating the steam soft measurement flow rate by using the comprehensive coefficient, the valve position data, the pressure difference correction coefficient, the steam pressure difference before and after the valve and the soft measurement constant; establishing the steam flow rate soft measurement instrument according to the steam flow rate soft measurement model.

4. The dilution ratio control method of the cracking device according to claim 3, wherein: the steam flow measurement model specifically comprises: wherein F is the actual steam flow rate, J is the measurement coefficient, d is the steam flow area, ε is the expandable coefficient, α is the steam flow coefficient, ΔP is the pressure difference before and after the valve, and ρ is the steam density.

5. The dilution ratio control method of the cracking device according to claim 3, wherein: the steam flow soft measurement model specifically comprises: wherein M is the steam soft measurement flow rate, K is the valve position coefficient, c is the comprehensive coefficient, x is the valve position real-time readable position, a is the pressure difference correction coefficient, b is the soft measurement constant, and ΔP is the pressure difference before and after the valve.

6. The method of claim 1, wherein the dilution ratio is controlled by adjusting the flow rate of the carrier gas. The step of allocating a steam demand flow rate to each reaction channel according to the target steam flow rate specifically comprises the following steps: allocating a steam individual target to each furnace according to the target steam flow rate and the number of furnaces; selecting the furnaces whose number of internal reaction channels cannot be evenly divided by the steam individual target as differential furnaces; setting a deviation variable for each reaction channel in each differential furnace; calculating the steam demand flow rate of each reaction channel in the differential furnace according to the steam individual target and the deviation variable.

7. The method of claim 6, wherein the dilution ratio is controlled by adjusting the flow rate of the dilution fluid. The step of adjusting the valve opening degree of each reaction channel according to the actual steam flow rate and the steam demand flow rate specifically comprises the following steps: calculating the steam adjustment amount of each reaction channel according to the actual steam flow rate and the steam demand flow rate; According to the current valve position of the valve in each reaction channel and the steam adjustment amount, a target control valve position corresponding to each reaction channel is calculated; The valve in each reaction channel is controlled respectively to adjust the corresponding valve position.

8. A computer apparatus comprising a memory, a processor, and a computer program on the memory, characterized in that, The processor executes the computer program to implement the steps of the dilution ratio control method of the cracking device according to any one of claims 1-7.

9. A computer readable storage medium having stored thereon computer programs / instructions, characterized in that, The computer program / instruction is executed by the processor to implement the steps of the dilution ratio control method of the cracking device according to any one of claims 1-7.

10. A computer program product comprising computer programs / instructions, characterized in that, The computer program / instruction is executed by the processor to implement the steps of the dilution ratio control method of the cracking device according to any one of claims 1-7.

Images