A Sulfur Ratio Control Method, Device, Computer Device, and Storage Medium

Abstract

The present application discloses a sulfur ratio control method, device, computer device and storage medium. The method includes: obtaining the acid gas concentration of the sulfur-making combustion furnace and the SO2 content in the discharged flue gas, and using real-time online optimization technology to find the optimal acid gas pressure set value; obtaining the measured acid gas pressure value of the sulfur-making combustion furnace, and calculating the target acid gas flow rate increment; calculating the acid gas flow rate set value; sending a corresponding control instruction to the acid gas regulating valve; obtaining the measured sulfur ratio value and the sulfur ratio set value of the sulfur-making combustion furnace; when the measured sulfur ratio value exceeds the first preset interval, calculating the target main air flow rate increment and the main air flow rate set value; sending a corresponding control instruction to the main air regulating valve, and when the measured sulfur ratio value exceeds the second preset interval, calculating the target pure oxygen flow rate increment and the pure oxygen flow rate set value; sending a corresponding control instruction to the pure oxygen regulating valve. The present application can realize the automatic adjustment of the operating load of the sulfur-making combustion furnace and the precise control of the sulfur ratio.

Description

Technical Field

[0001] The present application relates to the technical field of coal chemical industry, and particularly to a sulfur ratio control method, device, computer device, and storage medium. Background Art

[0002] The sulfur recovery unit is an acid gas treatment process unit in modern coal chemical and petrochemical industries, that is, an environmental protection unit, which is a key link to ensure that the acid gas index emitted during the production process meets the standards. Currently, the Claus process and technical route are mainly adopted in the market. The main devices of the Claus process include: sulfur-making combustion furnace, Claus reactor, waste gas incinerator, waste heat recovery, stripper, etc. The topic of optimizing the operation of the sulfur recovery unit has also attracted continuous and extensive research by researchers at home and abroad. Regarding the process modeling and optimization of the sulfur-making combustion furnace, due to factors such as the complexity and safety of process parameters, in some enterprises in the coal chemical or petrochemical industries, although the degree of automation is relatively high, there are very few applications of advanced control (APC) and online optimization control (RTO) that achieve actual effects.

[0003] The control of the sulfur-making combustion furnace is a complex multi-variable, pure time-delay, non-linear, strongly coupled, and slow time-varying system. Currently, the commonly used control method is mainly the conventional PID control. In some DCS systems, sulfur ratio control is added to establish the relationship between the oxygen enrichment amount, air amount, and acid gas amount. Due to the inherent process characteristics of the device, such as fluctuations in the feed amount (acid gas amount, air amount, oxygen enrichment amount, etc.), acid gas concentration, oxygen enrichment concentration, and serious coupling interference between control loops, the core process index (sulfur ratio) fluctuates greatly, and it is necessary to manually adjust the oxygen enrichment amount and acid gas amount frequently. Therefore, in actual operation control, even if the single loop is put into automatic control, it is still necessary to artificially interfere with the set value.

[0004] In other words, there are the following several ways to control the sulfur-making combustion furnace in the existing technical solutions currently:

[0005] (1) Generally, more often, DCS single-loop automatic control is used to supply the acid gas amount, oxygen enrichment amount, and air amount, or partial / full manual control is put into use. Its main defects are as follows: The conventional PID algorithm of single-loop automatic control is difficult to adapt to a control system with many disturbance variables, serious coupling, and pure time-delay like a gasifier. It requires operators to frequently perform manual interference and revise the set values of the acid gas amount, oxygen amount, and air amount, or manually directly adjust the main and auxiliary acid gas regulating valves, main and auxiliary air regulating valves, and oxygen enrichment regulating valves frequently to stabilize the core process index sulfur ratio of the sulfur-making combustion furnace. Such a control method has high requirements for the number, experience, experience, responsibility, and even physical strength of operators, and is prone to causing inconsistent, inaccurate, unstable, untimely, unoptimized, and unsafe system control.

[0006] (2) Some DCS systems add sulfur ratio control to establish the relationship between oxygen enrichment, air volume, and acid gas volume. However, due to its non-simple linear relationship, it is very sensitive to various disturbance variables and is difficult to adapt to actual operation. Considering safety, operators manually correct the flow setting value through the sulfur ratio to stabilize it. However, the precision control of the sulfur ratio still cannot achieve the required accuracy, and the optimization effect of the device is not significant.

[0007] (3) A few enterprises have added complex control to the sulfur-making combustion furnaces, and have achieved automatic control of the sulfur-making combustion furnaces through advanced control algorithms such as modeling and prediction. However, they only control the process indicators of the acid gas and air volume of the sulfur-making combustion furnaces. There is no method to achieve automatic load increase and decrease of the sulfur-making combustion furnaces and accurate control of the sulfur ratio. Each controlled variable is in an isolated control state, which often results in the phenomenon of losing sight of one thing while focusing on another. Summary of the invention

[0008] The present application provides a sulfur ratio control method, device, computer equipment and storage medium, which are intended to achieve automatic load lifting and lowering of a sulfur-producing combustion furnace and precise control of the sulfur ratio.

[0009] In a first aspect, a sulfur ratio control method comprises:

[0010] S1, obtain the acid gas concentration of the sulfur combustion furnace and the SO in the exhaust gas 2 content;

[0011] S2, according to the acid gas concentration of the sulfur-making combustion furnace and the SO in the exhaust flue gas 2 Based on the basic value of acid gas pressure, the optimal acid gas pressure setting value is found by using real-time online optimization technology;

[0012] S3, obtaining a measured value of the acid gas pressure of the sulfur-making combustion furnace, and calculating a target acid gas flow increment according to the acid gas pressure setting value and the acid gas pressure measured value;

[0013] S4, according to the target acid gas flow increment, based on the acid gas flow basic value, calculate the acid gas flow set value; obtain the acid gas flow measurement value of the sulfur-making combustion furnace, and according to the acid gas flow set value, send a corresponding control instruction to the acid gas regulating valve, so that the acid gas flow measurement value of the sulfur-making combustion furnace reaches or approaches the acid gas flow set value;

[0014] S5, obtaining a sulfur ratio measurement value and a sulfur ratio setting value of the sulfur-making combustion furnace;

[0015] S6. When the measured sulfur ratio value exceeds the first preset range, calculate the input air flow rate according to the set value and ratio of the acid gas flow rate; calculate the initial main air flow rate increment according to the measured sulfur ratio value and the set sulfur ratio value; calculate the target main air flow rate increment according to the initial main air flow rate increment and the input air flow rate; calculate the set value of the main air flow rate based on the basic value of the main air flow rate according to the target main air flow rate increment; obtain the measured value of the main air flow rate of the sulfur-making combustion furnace, and send a corresponding control command to the main air control valve according to the set value of the main air flow rate, so that the measured value of the main air flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the main air flow rate;

[0016] S7. When the measured sulfur ratio value exceeds the second preset range, calculate the target pure oxygen flow rate increment according to the measured sulfur ratio value and the set sulfur ratio value; calculate the set value of the pure oxygen flow rate based on the basic value of the pure oxygen flow rate according to the target pure oxygen flow rate increment; obtain the measured value of the pure oxygen flow rate of the sulfur-making combustion furnace, and send a corresponding control command to the pure oxygen control valve according to the set value of the pure oxygen flow rate, so that the measured value of the pure oxygen flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the pure oxygen flow rate.

[0017] Optionally, step S2 further includes:

[0018] According to the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas, use fuzzy predictive control technology to predict the basic value of the acid gas pressure.

[0019] Optionally, step S4 includes:

[0020] Calculate the target main acid gas flow rate increment and the target secondary acid gas flow rate increment according to the target acid gas flow rate increment;

[0021] Calculate the set value of the main acid gas flow rate based on the basic value of the main acid gas flow rate according to the target main acid gas flow rate increment; and calculate the set value of the secondary acid gas flow rate based on the basic value of the secondary acid gas flow rate according to the target secondary acid gas flow rate increment;

[0022] Obtain the measured value of the main acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control command to the main acid gas control valve according to the set value of the main acid gas flow rate, so that the measured value of the main acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the main acid gas flow rate; and obtain the measured value of the secondary acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control command to the secondary acid gas control valve according to the set value of the secondary acid gas flow rate, so that the measured value of the secondary acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the secondary acid gas flow rate.

[0023] Optionally, the first preset range is (1, 3), and the second preset range is (1.5, 2.5).

[0024] Optionally, the method further includes:

[0025] Obtaining historical production process data of the sulfur-making combustion furnace, and training a time-delay relationship model between multiple characteristic parameters in the historical production process data, sulfur ratio, and SO content in the finally discharged flue gas based on the sulfur ratio and SO content in the finally discharged flue gas; 2 content, training to obtain a time-delay relationship model between multiple characteristic parameters and the sulfur ratio and SO 2 content in the finally discharged flue gas;

[0026] Obtaining multiple characteristic parameters of the sulfur-making combustion furnace at the current moment, and inputting the multiple characteristic parameters of the sulfur-making combustion furnace at the current moment into the time-delay relationship model to predict the sulfur ratio and SO content in the discharged flue gas after a preset time interval; 2 content;

[0027] According to the SO content in the discharged flue gas after a preset time interval, based on the sulfur ratio after a preset time interval, using real-time online optimization technology to find the optimal sulfur ratio setting value. 2 content, based on the sulfur ratio after a preset time interval, using real-time online optimization technology to find the optimal sulfur ratio setting value.

[0028] Further optionally, the multiple characteristic parameters include the main and auxiliary acid gas flow rates, acid gas pressure, main and auxiliary air flow rates, oxygen enrichment amount, oxygen enrichment concentration, acid gas concentration, primary reaction outlet temperature, secondary reaction outlet temperature, raw flue gas volume, raw flue gas sulfur content, and sulfur content in the flue gas after the desulfurization tower.

[0029] In a second aspect, a sulfur ratio control device, characterized by comprising:

[0030] A first acquisition module, configured to acquire the acid gas concentration and SO content in the discharged flue gas of the sulfur-making combustion furnace; 2 content;

[0031] An acid gas pressure set value finding module, configured to find the optimal acid gas pressure set value based on the acid gas concentration and SO content in the discharged flue gas of the sulfur-making combustion furnace and using real-time online optimization technology based on the basic acid gas pressure value; 2 content, based on the basic acid gas pressure value, using real-time online optimization technology to find the optimal acid gas pressure set value;

[0032] A target acid gas flow rate increment calculation module, configured to acquire the measured acid gas pressure value of the sulfur-making combustion furnace, and calculate the target acid gas flow rate increment according to the acid gas pressure set value and the measured acid gas pressure value;

[0033] An acid gas flow rate adjustment module, configured to calculate the acid gas flow rate set value based on the target acid gas flow rate increment and the basic acid gas flow rate value; acquire the measured acid gas flow rate value of the sulfur-making combustion furnace, and send a corresponding control instruction to the acid gas regulating valve according to the acid gas flow rate set value, so that the measured acid gas flow rate value of the sulfur-making combustion furnace reaches or approaches the acid gas flow rate set value;

[0034] A second acquisition module, configured to acquire a sulfur ratio measurement value and a sulfur ratio set value of a sulfur combustion furnace;

[0035] A main air flow rate adjustment module, configured to, when the sulfur ratio measurement value exceeds a first preset range, calculate an input air flow rate according to the acid gas flow rate set value and the ratio; calculate an initial main air flow rate increment according to the sulfur ratio measurement value and the sulfur ratio set value; calculate a target main air flow rate increment according to the initial main air flow rate increment and the input air flow rate; calculate a main air flow rate set value based on the target main air flow rate increment and a basic main air flow rate value; acquire a main air flow rate measurement value of the sulfur combustion furnace, and send a corresponding control command to a main air control valve according to the main air flow rate set value, so that the main air flow rate measurement value of the sulfur combustion furnace reaches or approaches the main air flow rate set value;

[0036] An oxygen flow rate adjustment module, configured to, when the sulfur ratio measurement value exceeds a second preset range, calculate a target oxygen flow rate increment according to the sulfur ratio measurement value and the sulfur ratio set value; calculate an oxygen flow rate set value based on the target oxygen flow rate increment and a basic oxygen flow rate value; acquire an oxygen flow rate measurement value of the sulfur combustion furnace, and send a corresponding control command to an oxygen control valve according to the oxygen flow rate set value, so that the oxygen flow rate measurement value of the sulfur combustion furnace reaches or approaches the oxygen flow rate set value.

[0037] In a third aspect, a computer device includes a memory and a processor, the memory stores a computer program, and when the processor executes the computer program, the steps of the method according to any one of the first aspect are implemented.

[0038] In a fourth aspect, a computer-readable storage medium stores a computer program thereon, and when the computer program is executed by a processor, the steps of the method according to any one of the first aspect are implemented.

[0039] Compared with the prior art, the present application has at least the following beneficial effects:

[0040] In the sulfur ratio control method provided in the embodiments of the present application, by using real-time online optimization technology, the best acid gas pressure control point is obtained, and then according to the best acid gas pressure control point, the adjustment of the acid gas flow rate of the sulfur combustion furnace can be realized, so that the load of the sulfur combustion furnace can be adjusted according to the acid gas concentration of the sulfur combustion furnace and SO in the discharged flue gas 2The content automatically rises and falls, enabling the sulfur-making combustion furnace to automatically adjust the operating load and stabilize the system pressure, which can extend the operating cycle of the sulfur-making combustion furnace. Additionally, the sulfur ratio control method provided in the embodiments of the present application uses air as the main oxygen source and pure oxygen as an auxiliary supplementary process. According to different situations of the sulfur ratio measurement value, it precisely controls the sulfur ratio of the sulfur-making combustion furnace, improves the sulfur ratio accuracy, and optimizes the sulfur recovery rate. The present application can eliminate the hysteresis, inaccuracy, and instability caused by the existing system and manual operation, making the environmental protection indicators reach zero exceedance. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 FIG. is a schematic flow chart of a sulfur ratio control method provided by an embodiment of the present application;

[0042] Figure 2 FIG. is a specific flow chart of steps S1 - S4 in an embodiment of the present application;

[0043] Figure 3 FIG. is a specific flow chart of steps S5 - S7 in an embodiment of the present application;

[0044] Figure 4 FIG. is a specific block diagram of a signal processing model in an embodiment of the present application;

[0045] Figure 5 FIG. is a schematic diagram of a multivariable prediction model in an embodiment of the present application;

[0046] Figure 6 FIG. is a module architecture block diagram of a sulfur ratio control device provided by an embodiment of the present application;

[0047] Figure 7 FIG. is an internal structure diagram of a computer device provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] In order to make the objectives, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0049] In the description of the present application: Unless otherwise specified, "a plurality of" means two or more. Terms such as "first", "second", "third", etc. in the present application are intended to distinguish the objects being referred to and do not have special significance in terms of technical connotations (for example, they should not be understood as emphasizing importance or order, etc.). Expressions such as "including", "comprising", "having", etc. also mean "not limited to" (certain units, components, materials, steps, etc.).

[0050] In one embodiment, asFigure 1 As shown, a sulfur ratio control method is provided, including the following steps:

[0051] S1. Obtain the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas.

[0052] S2. Based on the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas, and based on the basic value of the acid gas pressure, use real-time online optimization technology to find the optimal set value of the acid gas pressure.

[0053] Specifically, the domestic industrial emission standards stipulate that the concentration of sulfur dioxide in the atmospheric pollutants discharged from thermal power plants, steel plants, petrochemical plants, etc. shall not exceed 35 mg / m³. Therefore, in the actual production process of the sulfur recovery unit, in order to balance production capacity and environmental protection requirements, the SO 2 content in the discharged flue gas can be made as close as possible to but not exceed 35 mg / m³.

[0054] At a certain acid gas concentration of the sulfur-making combustion furnace, by adjusting the set value of the acid gas pressure, the amount of acid gas entering the sulfur-making combustion furnace can be controlled, thereby controlling the load of the sulfur-making combustion furnace. Generally speaking, the acid gas pressure value of the sulfur-making combustion furnace needs to be maintained within a certain range, for example, it needs to be maintained at 70 - 120 kPa.

[0055] For example, the basic value of the acid gas pressure can be first set to 100 kPa, and then the basic value of the acid gas pressure is increased (or decreased) on the basis of 100 kPa to see whether the SO 2 content in the discharged flue gas will exceed the standard; if the SO 2 content in the flue gas will exceed the standard, the basic value of the acid gas pressure can be adjusted in the opposite direction. In the process of repeatedly revising the basic value of the acid gas pressure, the optimal set value of the acid gas pressure can be found, so that the SO 2 content in the discharged flue gas is as close as possible to but not exceed 35 mg / m³, and the load of the furnace can be increased or decreased according to the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas.

[0056] In addition, step S2 also includes:

[0057] Based on the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas, use fuzzy predictive control technology to predict the basic value of the acid gas pressure.

[0058] That is to say, through the fuzzy predictive control technology, a rough value of the acid gas pressure control point can be obtained. The real-time online optimization technology, that is, on the basis of the fuzzy predictive control, further adjusts the accuracy of the acid gas pressure control point. In other words, the fuzzy control is to roughly find an acid gas pressure control point, and the optimization control is to repeatedly find the best control point on the basis of this rough acid gas pressure control point. It can also be said that the fuzzy control first outputs a basic point, and the real-time online optimization technology is a compensation for the fuzzy control. Through the fuzzy predictive control technology, the robustness of the entire control system can be improved.

[0059] S3. Obtain the measured value of the acid gas pressure of the sulfur-making combustion furnace, and calculate the target acid gas flow rate increment according to the set value of the acid gas pressure and the measured value of the acid gas pressure.

[0060] According to the set value of the acid gas pressure and the measured value of the acid gas pressure, combined with the acid gas concentration, it is possible to calculate how much the acid gas flow rate needs to be changed so that the measured value of the acid gas pressure reaches the set value of the acid gas pressure. The specific calculation process belongs to the common knowledge of those skilled in the art and will not be elaborated here.

[0061] S4. Calculate the set value of the acid gas flow rate based on the target acid gas flow rate increment and the basic value of the acid gas flow rate; obtain the measured value of the acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the acid gas regulating valve according to the set value of the acid gas flow rate, so that the measured value of the acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the acid gas flow rate.

[0062] The set value of the acid gas flow rate is obtained by summing the target acid gas flow rate increment and the basic value of the acid gas flow rate.

[0063] Further, step S4 specifically includes:

[0064] Calculate the target main acid gas flow rate increment and the target secondary acid gas flow rate increment according to the target acid gas flow rate increment;

[0065] Calculate the set value of the main acid gas flow rate based on the target main acid gas flow rate increment and the basic value of the main acid gas flow rate; and calculate the set value of the secondary acid gas flow rate based on the target secondary acid gas flow rate increment and the basic value of the secondary acid gas flow rate;

[0066] Obtain the measured value of the main acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the main acid gas regulating valve according to the set value of the main acid gas flow rate, so that the measured value of the main acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the main acid gas flow rate; and obtain the measured value of the secondary acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the secondary acid gas regulating valve according to the set value of the secondary acid gas flow rate, so that the measured value of the secondary acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the secondary acid gas flow rate.

[0067] Among them, the target main acid gas flow rate increment and the target secondary acid gas flow rate increment can be calculated according to a preset acid gas distribution rule or a preset algorithm.

[0068] In other words, steps S1 - S4 are for the sulfur recovery system to achieve automatic and intelligent load lifting and lowering. Using the acid gas pressure as the load disturbance observation signal of the sulfur recovery system, a pre-control module corrects the control point of the acid gas flow rate into the furnace. At the same time, using the acid gas concentration and the hourly average value of SO in the finally discharged flue gas of the system 2 to predict and optimize the acid gas pressure setting, so that its fluctuation is always at the optimal control point, realizing automatic adjustment of the sulfur recovery operation load and stabilizing the system pressure, while extending the operation cycle of the combustion furnace. The flowchart of the load control loop APC + RTO control scheme reflected by steps S1 - S4 can also be seen in Figure 2 . In Figure 2 , TOP is the optimization time, SOP is the optimization step size, and EOP is the optimization accuracy.

[0069] S5, obtain the sulfur ratio measurement value and the sulfur ratio set value of the sulfur-making combustion furnace.

[0070] S6, when the sulfur ratio measurement value exceeds the first preset interval, calculate the input air flow rate according to the acid gas flow rate set value and the ratio; calculate the initial main air flow rate increment according to the sulfur ratio measurement value and the sulfur ratio set value; calculate the target main air flow rate increment according to the initial main air flow rate increment and the input air flow rate; calculate the main air flow rate set value based on the basic value of the main air flow rate according to the target main air flow rate increment; obtain the main air flow rate measurement value of the sulfur-making combustion furnace, and send a corresponding control command to the main air control valve according to the main air flow rate set value, so that the main air flow rate measurement value of the sulfur-making combustion furnace reaches or approaches the main air flow rate set value.

[0071] Among them, the first preset interval is (1, 3). Exceeding the first preset interval means that the sulfur ratio measurement value is less than 1 or greater than 3.

[0072] The input air flow rate is obtained by multiplying the acid gas flow rate set value and the ratio; the target main air flow rate increment is obtained by summing the initial main air flow rate increment and the input air flow rate. The input air flow rate can reflect the air flow rate that has been input into the sulfur-making combustion furnace at present, and the target main air flow rate increment can reflect how much more main air flow rate is needed to reach the initial main air flow rate increment.

[0073] S7. When the measured sulfur ratio value exceeds the second preset range, calculate the target pure oxygen flow rate increment based on the measured sulfur ratio value and the set sulfur ratio value; calculate the set pure oxygen flow rate based on the target pure oxygen flow rate increment and the basic pure oxygen flow rate value; obtain the measured pure oxygen flow rate of the sulfur-making combustion furnace, and send a corresponding control command to the pure oxygen regulating valve according to the set pure oxygen flow rate, so that the measured pure oxygen flow rate of the sulfur-making combustion furnace reaches or approaches the set pure oxygen flow rate.

[0074] Among them, the second preset range is (1.5, 2.5). Exceeding the second preset range means that the measured sulfur ratio value is less than 1.5 or greater than 2.5.

[0075] In other words, steps S5 - S7 are for the sulfur recovery system to achieve precise control of the sulfur ratio. Theoretically, when the molar ratio of H 2 S to SO 2 is 2:1, the conversion rate of S in the Claus reactor is the highest. An important operation to achieve this ratio is to quickly, accurately, stably, and optimally control the amount of O 2 required for the chemical combustion reaction in the sulfur-making furnace to change with the acid gas flow rate and composition. There are two processes for adding O 2 , one is to add air, and the other is to add pure oxygen. If the enterprise has an abundance of pure oxygen, pure oxygen can be preferentially used, which can improve the operation quality of H 2 S / SO 2 and reduce energy consumption and the ineffective load of the device.

[0076] The key points of the loop design in this application are (taking the case where air is the main oxygen source, pure oxygen is used as an auxiliary supplementary process, and the air addition is designed with a large and small valve): taking the sum of the acid gas flow rate control points * ratio as the main air flow rate control point, and when H 2 S / SO 2 exceeds the range of 1 - 3, the first-stage control 1 and 2 quickly and roughly adjust H 2 S / SO 2 through the large air valve; when H 2 S / SO 2 exceeds the range of 1.5 - 2.5, the pure oxygen first-stage control 3 and 4 quickly and finely adjust H 2 S / SO 2 through the pure oxygen control valve; usually, the first-stage control 5 finely adjusts H 2 S / SO 2 through the small air valve. Of course, the air valve and the oxygen valve can also be adjusted simultaneously to improve the control quality.

[0077] Another schematic diagram of the process of steps S5 - S7 can also be seen in Figure 3 . In Figure 3Among them, the algorithms and model parameters enabled by each advanced control model vary in strength. The optimal action weights need to be designed, and the disturbance-free switching function that can achieve the optimal control index even when using pure oxygen or even when only one valve is used, as well as the coordination algorithm when the air large and small valves are enabled simultaneously, need to be considered. Also, the disturbance-free sorting function responsible for correcting the control point by the advanced control increment output needs to be designed.

[0078] Each advanced control model mainly includes functions such as variable-proportion variable-integral PID, disturbance observer, soft servo, overlap, adaptation, and self-tuning, which are built with different combinations according to the actual on-site process. Among them, the disturbance observer: makes an advance prediction dynamically based on on-site parameters, and further makes an advance prediction on the basis of mechanism modeling to improve the accuracy of control indicators. For example, H 2 S / SO 2 precision control; soft servo: models according to the performance of on-site actuators, and imitates manual control with good robustness, which has a good effect on solving pure lag. For example, the sulfur ratio analyzer has a lag of about 5 minutes. In addition, the block diagram of the signal processing model in the control scheme can be seen in Figure 4 .

[0079] Furthermore, the method further includes:

[0080] Obtain the historical production process data of the sulfur-making combustion furnace, and train a time-delay relationship model between multiple characteristic parameters in the historical production process data, the sulfur ratio, and the SO 2 content in the finally discharged flue gas; 2 content in the finally discharged flue gas;

[0081] Obtain multiple characteristic parameters of the sulfur-making combustion furnace at the current moment, and input the multiple characteristic parameters of the sulfur-making combustion furnace at the current moment into the time-delay relationship model to predict the sulfur ratio and the SO 2 content in the discharged flue gas after a preset time interval;

[0082] According to the SO 2 content in the discharged flue gas after a preset time interval, and based on the sulfur ratio after a preset time interval, use real-time online optimization technology to find the optimal sulfur ratio setting value.

[0083] Among them, the multiple characteristic parameters include the main and auxiliary acid gas flow rates, acid gas pressure, main and auxiliary air flow rates, oxygen enrichment amount, oxygen enrichment concentration, acid gas concentration, primary reaction outlet temperature, secondary reaction outlet temperature, raw flue gas volume, raw flue gas sulfur content, and sulfur content in the flue gas after the desulfurization tower.

[0084] In other words, the sulfur combustion furnace has many parameters, with serious mutual coupling interference and a complex mechanism model. In establishing a prediction model, it is necessary to analyze and screen a large amount of historical data on the basis of a deep understanding of the process, mark and process abnormal factors such as abnormal faults, and assist in the judgment of reaction mechanisms and experience, so that the established model conforms to the actual situation and has adaptability. The main characteristic parameters adopted by the model include the main and auxiliary acid gas flow rates, acid gas pressure, main and auxiliary air flow rates, oxygen enrichment amount, oxygen enrichment concentration, acid gas concentration, the outlet temperatures of the first and second-stage reactions, the original flue gas volume, as well as the sulfur content in the original flue gas and the sulfur content in the flue gas after the desulfurization tower, etc. The sulfur combined ratio, the SO 2 content in the final flue gas, etc. are used as the optimization target parameters.

[0085] On the basis of the preprocessing and feature extraction of historical production process data, a deep recurrent neural network is used to discover and extract the time-delay relationship model between the production process data and the sulfur ratio and the SO 2 content in the final flue gas. Then, this time-delay relationship model is used to predict the sulfur ratio and the SO 2 content in the final flue gas several minutes or even ten minutes after the current moment starting from the real-time working conditions. The optimization control system timely adjusts the usage amounts (valves) of acid gas, air, and oxygen enrichment according to the prediction results. The control scheme of the neural network multivariable prediction model for the sulfur recovery system is as Figure 5 shown.

[0086] On the basis of establishing the prediction model, a set of best control point setting combinations that match the current working conditions and have global optimal characteristics are found by using real-time online optimization technology (RTO). After passing the effectiveness verification, the best control point setting combinations are transmitted to the APC control system to complete real-time optimization and optimization closed-loop control, so that the sulfur combustion furnace system always operates in the best state.

[0087] The sulfur combustion furnace is the core part of the sulfur recovery device in coal chemical and petrochemical plants. An accurate and reliable intelligent control scheme for the sulfur combustion furnace based on APC+RTO plays a crucial role in implementing the production process optimization of the sulfur recovery device. Aiming at the characteristics of the sulfur combustion furnace system such as multivariable, pure time-delay, nonlinear, strong coupling, and slow time-varying, the method provided by the embodiments of this application realizes full-automatic advanced control such as precise control of the sulfur ratio and automatic load lifting control of the sulfur combustion furnace through advanced control methods such as multivariable model predictive control and real-time online optimization technology, achieves rapid tracking of the load of the sulfur recovery device, eliminates the hysteresis, inaccuracy, and instability caused by the existing system and manual operation, and makes the environmental protection indicators reach zero exceedance.

[0088] In the above optimization control of the sulfur recovery device, both the sulfur ratio and the flue gas SO 2Taking the optimization target, an optimization control strategy of "double optimization" is adopted. Through the optimization of operating parameters, the optimal pressure control point is obtained, the sulfur recovery unit is enabled to automatically adjust the operating load and stabilize the system pressure, and at the same time, the operating cycle of the combustion furnace is extended (the intake air volume is smoothly controlled to reduce the internal structure bearing force of the combustion furnace caused by excessive intake air volume concentration). Through the optimization of operating parameters, the system can automatically and intelligently increase and decrease the load, improve the accuracy of the sulfur ratio, and achieve the best sulfur recovery rate.

[0089] Combining the deep neural network technology and the real-time rolling optimization technology, it is used for the establishment and optimization control of the sulfur recovery unit optimization prediction model, which is applicable to the situation where there are many sulfur recovery parameters, serious mutual coupling interference, and complex mechanism models, improving the accuracy and effectiveness of the model, enabling the system to achieve closed-loop optimization, and improving the operating efficiency of the sulfur recovery system through precise control of the sulfur ratio.

[0090] This application realizes the precise control of the sulfur ratio for automatic load increase and decrease. For the automatic load increase and decrease of the sulfur recovery unit and the precise control of the sulfur ratio, it enables the intelligent production scheduling and stable and optimal operation of the sulfur recovery unit.

[0091] In one embodiment, as Figure 6 shown, a sulfur ratio control device is provided, including the following program modules:

[0092] The first acquisition module 601 is used to acquire the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas;

[0093] The acid gas pressure set value searching module 602 is used to search for the best acid gas pressure set value based on the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas, and using the real-time online optimization technology based on the basic value of the acid gas pressure;

[0094] The target acid gas flow rate increment calculation module 603 is used to acquire the measured value of the acid gas pressure of the sulfur-making combustion furnace, and calculate the target acid gas flow rate increment according to the acid gas pressure set value and the measured value of the acid gas pressure;

[0095] The acid gas flow rate adjustment module 604 calculates the acid gas flow rate set value based on the target acid gas flow rate increment and the basic value of the acid gas flow rate; acquires the measured value of the acid gas flow rate of the sulfur-making combustion furnace, and sends a corresponding control instruction to the acid gas regulating valve according to the acid gas flow rate set value, so that the measured value of the acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the acid gas flow rate set value;

[0096] The second acquisition module 605 is used to acquire the measured value and the set value of the sulfur ratio of the sulfur-making combustion furnace;

[0097] The main air flow adjustment module 606 is configured to calculate the input air flow according to the acid gas flow set value and the ratio when the measured sulfur ratio value exceeds the first preset range; calculate the initial main air flow increment according to the measured sulfur ratio value and the set sulfur ratio value; calculate the target main air flow increment according to the initial main air flow increment and the input air flow; calculate the main air flow set value based on the basic main air flow value according to the target main air flow increment; obtain the measured main air flow value of the sulfur-making combustion furnace, and send a corresponding control command to the main air control valve according to the main air flow set value, so that the measured main air flow value of the sulfur-making combustion furnace reaches or approaches the main air flow set value;

[0098] The pure oxygen flow adjustment module 607 is configured to calculate the target pure oxygen flow increment according to the measured sulfur ratio value and the set sulfur ratio value when the measured sulfur ratio value exceeds the second preset range; calculate the pure oxygen flow set value based on the basic pure oxygen flow value according to the target pure oxygen flow increment; obtain the measured pure oxygen flow value of the sulfur-making combustion furnace, and send a corresponding control command to the pure oxygen control valve according to the pure oxygen flow set value, so that the measured pure oxygen flow value of the sulfur-making combustion furnace reaches or approaches the pure oxygen flow set value.

[0099] The specific implementation content of each module can refer to the limitation of a sulfur ratio control method in the above text, and will not be elaborated here.

[0100] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in Figure 7 The figure. The computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities, and the communication interface is used to communicate with an external terminal in a wired or wireless manner. The wireless manner can be achieved through WIFI, a carrier network, NFC (Near Field Communication), or other technologies. The computer device realizes the above-mentioned sulfur ratio control method by loading and running a computer program. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covered on the display screen, or a button, a trackball, or a touchpad provided on the housing of the computer device, or an external keyboard, touchpad, or mouse, etc.

[0101] Those skilled in the art can understand that Figure 7 The structure shown in is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0102] In one embodiment, a computer-readable storage medium is further provided, on which a computer program is stored, which relates to all or part of the processes in the method of the above embodiment.

[0103] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

Claims

1. A sulfur ratio control method, characterized in that, comprising: S1. Obtain the acid gas concentration of the sulfur-making combustion furnace and the SO content in the discharged flue gas. 2 Content; S2. According to the acid gas concentration of the sulfur-making combustion furnace and the SO content in the discharged flue gas, based on the basic value of the acid gas pressure, use real-time online optimization technology to find the optimal set value of the acid gas pressure; 2 Content, based on the basic value of the acid gas pressure, use real-time online optimization technology to find the optimal set value of the acid gas pressure; S3. Obtain the measured value of the acid gas pressure of the sulfur-making combustion furnace, and calculate the target acid gas flow rate increment according to the set value of the acid gas pressure and the measured value of the acid gas pressure; S4. Calculate the set value of the acid gas flow rate based on the basic value of the acid gas flow rate according to the target acid gas flow rate increment; obtain the measured value of the acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the acid gas regulating valve according to the set value of the acid gas flow rate, so that the measured value of the acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the acid gas flow rate; S5. Obtain the measured value of the sulfur ratio and the set value of the sulfur ratio of the sulfur-making combustion furnace; S6. When the measured value of the sulfur ratio exceeds the first preset interval, calculate the input air flow rate according to the set value of the acid gas flow rate and the ratio; Calculate the initial main air flow rate increment according to the measured value of the sulfur ratio and the set value of the sulfur ratio; Calculate the target main air flow rate increment according to the initial main air flow rate increment and the input air flow rate; Calculate the set value of the main air flow rate based on the basic value of the main air flow rate according to the target main air flow rate increment; Obtain the measured value of the main air flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the main air regulating valve according to the set value of the main air flow rate, so that the measured value of the main air flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the main air flow rate; S7. When the measured value of the sulfur ratio exceeds the second preset interval, calculate the target pure oxygen flow rate increment according to the measured value of the sulfur ratio and the set value of the sulfur ratio; Calculate the set value of the pure oxygen flow rate based on the basic value of the pure oxygen flow rate according to the target pure oxygen flow rate increment; obtain the measured value of the pure oxygen flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the pure oxygen regulating valve according to the set value of the pure oxygen flow rate, so that the measured value of the pure oxygen flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the pure oxygen flow rate.

2. The sulfur ratio control method according to claim 1, characterized in that, step S2 further includes: According to the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas, the basic value of the acid gas pressure is predicted by using fuzzy predictive control technology.

3. The sulfur ratio control method according to claim 1, characterized in that, step S4 includes: Calculate the target main acid gas flow rate increment and the target secondary acid gas flow rate increment according to the target acid gas flow rate increment; Calculate the set value of the main acid gas flow rate based on the basic value of the main acid gas flow rate according to the target main acid gas flow rate increment; and calculate the set value of the secondary acid gas flow rate based on the basic value of the secondary acid gas flow rate according to the target secondary acid gas flow rate increment; Obtain the measured value of the main acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the main acid gas regulating valve according to the set value of the main acid gas flow rate, so that the measured value of the main acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the main acid gas flow rate; and obtain the measured value of the secondary acid gas flow rate of the sulfur-making combustion furnace, and send a corresponding control instruction to the secondary acid gas regulating valve according to the set value of the secondary acid gas flow rate, so that the measured value of the secondary acid gas flow rate of the sulfur-making combustion furnace reaches or approaches the set value of the secondary acid gas flow rate.

4. The sulfur ratio control method according to claim 1, characterized in that, the first preset interval is (1, 3), and the second preset interval is (1.5, 2.5).

5. The sulfur ratio control method according to claim 1, characterized in that, the method further includes: Obtain the historical production process data of the sulfur-making combustion furnace, and based on multiple characteristic parameters in the historical production process data, as well as the sulfur ratio and the SO content in the finally discharged flue gas, train a time-delay relationship model between the multiple characteristic parameters and the sulfur ratio and the SO content in the finally discharged flue gas; 2 content, train a time-delay relationship model between the multiple characteristic parameters and the sulfur ratio and the SO 2 content in the finally discharged flue gas; Obtain multiple characteristic parameters of the sulfur-making combustion furnace at the current moment, and input the multiple characteristic parameters of the sulfur-making combustion furnace at the current moment into the time-delay relationship model to predict the sulfur ratio and the SO content in the discharged flue gas after a preset time interval. 2 content; Based on the SO content in the flue gas discharged after a preset time interval, and based on the sulfur ratio after the preset time interval, use real-time online optimization technology to find the optimal sulfur ratio setting value. 2 ​ 6. The sulfur ratio control method according to claim 5, characterized in that, the multiple characteristic parameters include the main and auxiliary acid gas flow rates, acid gas pressure, main and auxiliary air flow rates, oxygen enrichment amount, oxygen enrichment concentration, acid gas concentration, primary reaction outlet temperature, secondary reaction outlet temperature, raw flue gas volume, raw flue gas sulfur content, and sulfur content of the flue gas after the desulfurization tower.

7. A sulfur ratio control device, characterized in that, it includes: The first acquisition module is used to acquire the acid gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas; The sour gas pressure set value finding module is used to find the optimal sour gas pressure set value based on the basic value of the sour gas pressure by using real-time online optimization technology according to the sour gas concentration of the sulfur-making combustion furnace and the SO 2 content in the discharged flue gas; A target acid gas flow rate increment calculation module, configured to obtain the measured value of the acid gas pressure of the sulfur production combustion furnace, and calculate the target acid gas flow rate increment according to the set value of the acid gas pressure and the measured value of the acid gas pressure; An acid gas flow rate adjustment module, configured to calculate the set value of the acid gas flow rate based on the basic value of the acid gas flow rate according to the target acid gas flow rate increment; obtain the measured value of the acid gas flow rate of the sulfur production combustion furnace, and send a corresponding control instruction to the acid gas regulating valve according to the set value of the acid gas flow rate, so that the measured value of the acid gas flow rate of the sulfur production combustion furnace reaches or approaches the set value of the acid gas flow rate; A second acquisition module, configured to obtain the measured value and set value of the sulfur ratio of the sulfur production combustion furnace; A main air flow rate adjustment module, configured to calculate the input air flow rate according to the set value of the acid gas flow rate and the ratio when the measured value of the sulfur ratio exceeds the first preset interval; calculate the initial main air flow rate increment according to the measured value and set value of the sulfur ratio; calculate the target main air flow rate increment according to the initial main air flow rate increment and the input air flow rate; calculate the set value of the main air flow rate based on the basic value of the main air flow rate according to the target main air flow rate increment; obtain the measured value of the main air flow rate of the sulfur production combustion furnace, and send a corresponding control instruction to the main air regulating valve according to the set value of the main air flow rate, so that the measured value of the main air flow rate of the sulfur production combustion furnace reaches or approaches the set value of the main air flow rate; A pure oxygen flow rate adjustment module, configured to calculate the target pure oxygen flow rate increment according to the measured value and set value of the sulfur ratio when the measured value of the sulfur ratio exceeds the second preset interval; calculate the set value of the pure oxygen flow rate based on the basic value of the pure oxygen flow rate according to the target pure oxygen flow rate increment; obtain the measured value of the pure oxygen flow rate of the sulfur production combustion furnace, and send a corresponding control instruction to the pure oxygen regulating valve according to the set value of the pure oxygen flow rate, so that the measured value of the pure oxygen flow rate of the sulfur production combustion furnace reaches or approaches the set value of the pure oxygen flow rate.

8. A computer device, including a memory and a processor, the memory stores a computer program, characterized in that, when the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium, on which a computer program is stored, characterized in that, when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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