Three-layer air pipeline flow optimization control system of zinc rectifying furnace

Abstract

The invention discloses a three-layer air pipeline flow optimization control system of a zinc rectifying furnace, which comprises a flow monitoring module, a flow control module and a flow regulation execution module, and is characterized in that the flow monitoring module and the flow regulation execution module are respectively connected with the flow control module, and the flow control module is internally provided with a set target air flow proportion; according to the three-layer air pipeline flow optimization control system of the zinc rectifying furnace, the air flow in the three-layer air pipeline is monitored in real time, the real-time air flow proportion of the three-layer air pipeline is obtained through the flow control module, and the three-layer air pipeline flow optimization control system of the zinc rectifying furnace is controlled according to the target air flow proportion. The air flow proportion of the three layers of air pipelines is rapidly adjusted, accurate control over the air flow proportion of the three layers of air pipelines is achieved, and therefore complete combustion of gas in the furnace is promoted, and the combustion efficiency of natural gas is improved.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical equipment, and in particular to a three-layer air duct flow optimization control system for a zinc rectification furnace. Background Art

[0002] As a key equipment in the pyrometallurgical zinc smelting process, the tower zinc distillation furnace uses the principle of continuous fractionation to separate the impurity metals (mainly lead, iron, cadmium, etc.) in crude zinc according to the different boiling points of the metals to obtain refined zinc or 1-3 grade zinc. It has the advantages of high zinc purity, strong raw material adaptability, and the ability to enrich other metals at the same time. In the zinc distillation furnace, the three-layer air duct is an important part, responsible for providing the air required for natural gas combustion. Reasonable air flow distribution is conducive to the full combustion of natural gas air in the combustion chamber of the zinc refiner, making the temperature distribution in the tower plate more reasonable.

[0003] The existing tower zinc distillation furnace is prone to incomplete combustion of natural gas and low efficiency of natural gas combustion due to the unreasonable and unstable air flow distribution in the three-layer air duct. In addition, it will also cause local high temperature problems in the furnace, which is not conducive to safe production. Summary of the invention

[0004] In view of the problems existing in the three-layer air duct of the tower zinc distillation furnace, the present invention provides a three-layer air duct flow optimization control system for the zinc distillation furnace, which at least solves one problem existing in the prior art and has the characteristics of promoting the complete combustion of the gas in the furnace, improving the combustion efficiency of natural gas and preventing the formation of local high-temperature points.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a three-layer air duct flow optimization control system of a zinc distillation furnace, the zinc distillation furnace includes a combustion chamber and an air duct, including a flow monitoring module, a flow control module and a flow regulation execution module, the flow monitoring module and the flow regulation execution module are respectively connected to the flow control module, the flow control module has a built-in set target air flow ratio, the flow monitoring module and the flow regulation execution module are arranged in the air duct, the flow monitoring module monitors the air flow in the air duct and transmits real-time air flow data to the flow control module, the flow control module obtains the real-time air flow ratio according to the real-time air flow data, and obtains the air flow adjustment data according to the real-time air flow ratio and the target air flow ratio, the flow control module outputs a control instruction to the flow regulation execution module, and the flow regulation execution module adjusts the air flow in the air duct according to the control instruction.

[0006] Furthermore, the flow control module adopts a PLC controller, the air duct includes a branch air duct, the branch air duct is a three-layer air duct structure, the flow monitoring module is arranged in the branch air duct, and is used to monitor the air flow in the branch air duct, and the flow regulation execution module is arranged in the branch air duct, and is used to regulate the air flow in the air duct.

[0007] Furthermore, the branch air duct includes a first-layer air duct, a second-layer air duct and a third-layer air duct, the flow monitoring module includes a first-layer air flow sensor, a second-layer air flow sensor and a third-layer air flow sensor, and the flow regulation execution module includes a first-layer air flow regulating valve, a second-layer air flow regulating valve and a third-layer air flow regulating valve.

[0008] Furthermore, the first-layer air flow sensor and the first-layer air flow regulating valve are arranged in the first-layer air duct, the first-layer air flow sensor monitors the air flow data in the first-layer air duct and transmits the data to the PLC controller, and the first-layer air flow regulating valve adjusts the flow cross-section of the air in the first-layer air duct according to the instructions of the PLC controller; the second-layer air flow sensor and the second-layer air flow regulating valve are arranged in the second-layer air duct, the second-layer air flow sensor monitors the air flow data in the second-layer air duct and transmits the data to the PLC controller, and the second-layer air flow regulating valve adjusts the flow cross-section of the air in the second-layer air duct according to the instructions of the PLC controller; the third-layer air flow sensor and the third-layer air flow regulating valve are arranged in the third-layer air duct, the third-layer air flow sensor monitors the air flow data in the third-layer air duct and transmits the data to the PLC controller, and the third-layer air flow regulating valve adjusts the flow cross-section of the air in the third-layer air duct according to the instructions of the PLC controller.

[0009] Furthermore, the target air flow ratio is the real-time air flow ratio of the first-layer air duct, the second-layer air duct and the third-layer air duct, and the target air flow ratio is set to 0.33:0.38:0.29.

[0010] Furthermore, the sampling times of the flow monitoring module are fed back through the relative measurement error. The flow measurement cycle is divided into two stages. The first stage is the relative measurement error calculation stage, and the second stage is the sampling times adjustment stage. The sampling times of the second stage are adjusted by the relative measurement error calculated in the first stage. After the sampling times adjustment of the second stage is completed, the flow data measured in this stage are calculated to obtain the final flow size.

[0011] Furthermore, the calculation formula of the relative measurement error is:

[0012]

[0013]

[0014]

[0015] The average flow rate measured in the first stage;

[0016] q i : The flow rate of the ith sampling in the 20 samplings in the first stage, q min With q max are the minimum and maximum flow rates in the 20 samplings in the first stage;

[0017] The average error of the first stage measurement;

[0018] q' i : The size of the i-th sampling flow rate in the 18 samplings except the minimum sampling flow rate and the maximum sampling flow rate in the first stage;

[0019] τ c : Relative measurement error.

[0020] Furthermore, the calculation formula for the sampling adjustment times is:

[0021]

[0022] τ0: initial relative measurement error, τ0 is 0.05;

[0023] n: sampling adjustment times, which is an integer based on the calculation result. The maximum sampling adjustment times shall not exceed 240 times.

[0024] Furthermore, the calculation formula of the final measured flow rate is:

[0025]

[0026] The final measured flow rate;

[0027] q" i : The size of the i-th sampling flow in the sampling flow except the minimum sampling flow and the maximum sampling flow in the second stage.

[0028] Furthermore, the air flow ratio control uses a proportional scaling rate to provide feedback on the control adjustment time. The air flow ratio scaling rate and the control adjustment time calculation formula are:

[0029] Q a =1-T a / T a0

[0030]

[0031] T a : Control adjustment time of air flow ratio

[0032] Q a : Scaling ratio of air flow ratio;

[0033] T a0 : Initial adjustment time of air flow ratio, 120 minutes;

[0034] R a12，1 : After the system adjusts the device for controlling the air flow ratio, the PLC controller initially calculates the air flow ratio of the first-layer air duct and the second-layer air duct based on the air flow data monitored by the flow monitoring module. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes;

[0035] R a23，1 : After the system adjusts the device for controlling the air flow ratio, the PLC controller initially calculates the air flow ratio of the second-layer air duct and the third-layer air duct based on the air flow data monitored by the flow monitoring module. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes;

[0036] R a12，2 : Before the system adjusts the air flow ratio, the air flow ratio of the first-layer air duct and the second-layer air duct is calculated by the PLC controller for the air flow data monitored by the flow monitoring module for the last time. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module every 20 minutes;

[0037] R a23，2 : Before the system adjusts the air flow ratio, the PLC controller calculates the air flow ratio of the second-layer air duct and the third-layer air duct based on the air flow data monitored by the flow monitoring module for the last time. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes.

[0038] In summary, the present invention is beneficial in that:

[0039] The three-layer air duct flow optimization control system of the zinc distillation furnace of the present invention monitors the air flow in the three-layer air duct in real time, obtains the real-time air flow ratio of the three-layer air duct through the flow control module, and quickly adjusts the air flow ratio of the three-layer air duct according to the target air flow ratio, thereby achieving precise control of the air flow ratio of the three-layer air duct, thereby promoting the complete combustion of the gas in the furnace and improving the combustion efficiency of natural gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the air duct flow optimization control system of the present invention;

[0041] Figure 2 It is a distribution diagram of the air flow sensor and the air flow regulator of the present invention;

[0042] Figure 3 It is a schematic diagram of the monitoring cross section in the combustion chamber of the zinc rectification furnace of the present invention;

[0043] Figure 4 The temperature distribution cloud diagram of the combustion chamber l1 section at different air flow ratios of the present invention;

[0044] Figure 5 The temperature distribution cloud diagram of the outer wall of the tower tray at different air flow ratios of the present invention;

[0045] Figure 6a This is a graph showing the change of the average heat flux density on the outer wall of the tray as the air flow rate ratio increases in the present invention;

[0046] Figure 6b This is a graph showing the change of the average temperature of the outer wall of the tower tray in the present invention as the air flow rate ratio increases;

[0047] Figure 7 This is a graph showing the change of the total reaction heat of air combustion in the combustion chamber of the zinc rectification furnace in the present invention as the air flow rate ratio increases;

[0048] Figure 8 This is a graph showing the change in concentration of chemical components in flue gas at the bottom outlet of the combustion chamber of the zinc rectification furnace of the present invention as the air flow rate ratio increases.

[0049] Symbols in the figure: combustion chamber 1, air duct 2, main air duct 20, first-layer air duct 21, second-layer air duct 22, third-layer air duct 23, first-layer air flow sensor 41, second-layer air flow sensor 42, third-layer air flow sensor 43, first-layer air flow regulating valve 44, second-layer air flow regulating valve 45, third-layer air flow regulating valve 46. DETAILED DESCRIPTION

[0050] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0051] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0052] All directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, horizontal, vertical...) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0053] Due to installation errors and other reasons, the parallel relationship referred to in the embodiments of the present invention may actually be an approximately parallel relationship, and the vertical relationship may actually be an approximately vertical relationship.

[0054] Embodiment 1:

[0055] like Figure 1 As shown, a three-layer air duct flow optimization control system of a zinc distillation furnace of the present invention, the zinc distillation furnace comprises a combustion chamber 1 and an air duct 2, air is introduced into the combustion chamber 1 through the air duct 2, the control system comprises a flow monitoring module, a flow control module and a flow regulation execution module, the flow monitoring module and the flow regulation execution module are respectively connected to the flow control module, the flow control module has a built-in set target air flow ratio, the flow monitoring module and the flow regulation execution module are arranged in the air duct 2, the flow monitoring module monitors the air flow in the air duct and transmits real-time air flow data to the flow control module, the flow control module obtains the real-time air flow ratio according to the real-time air flow data, and obtains the air flow adjustment data according to the real-time air flow ratio and the target air flow ratio, the flow control module outputs a control instruction to the flow regulation execution module, and the flow regulation execution module adjusts the air flow in the air duct 2 according to the control instruction.

[0056] The air duct 2 includes a main air duct 20 and branch air ducts. The branch air duct is a three-layer air duct structure, including a first-layer air duct 21, a second-layer air duct 22 and a third-layer air duct 23. The inlet ends of the first-layer air duct 21, the second-layer air duct 22 and the third-layer air duct 23 are respectively connected to the main air duct 20, and the outlet ends are connected to the combustion chamber 1. The air is drawn in by the fan 201 arranged in the main air duct 20, and enters the combustion chamber 1 through the main air duct 20, the first-layer air duct 21, the second-layer air duct 22 and the third-layer air duct 23.

[0057] The flow control module adopts a PLC controller. The PLC controller obtains the real-time air flow ratio based on the received real-time air flow data, and obtains the air flow adjustment data based on the real-time air flow ratio and the built-in target air flow ratio, and generates control instructions at the same time. The PLC controller outputs the control instructions to the flow regulation execution module.

[0058] The flow monitoring module is arranged in the branch air duct to monitor the air flow in the branch air duct. The flow monitoring module includes a first-layer air flow sensor 41, a second-layer air flow sensor 42 and a third-layer air flow sensor 43; the first-layer air flow sensor 41, the second-layer air flow sensor 42 and the third-layer air flow sensor 43 are respectively connected to the flow control module.

[0059] The flow regulation execution module is arranged in the branch air duct, and is used to regulate the air flow in the air duct 2. The flow regulation execution module includes a first-layer air flow regulating valve 44, a second-layer air flow regulating valve 45 and a third-layer air flow regulating valve 46. The first-layer air flow regulating valve 44, the second-layer air flow regulating valve 45 and the third-layer air flow regulating valve 46 are respectively connected to the PLC controller.

[0060] The first-layer air flow sensor 41 and the first-layer air flow regulating valve 44 are arranged in the first-layer air duct 21. The first-layer air flow sensor 41 monitors the air flow data in the first-layer air duct 21 and transmits the data to the PLC controller. The first-layer air flow regulating valve 44 adjusts the flow cross-section of the air in the first-layer air duct 21 according to the instruction of the PLC controller, thereby adjusting the air flow in the first-layer air duct 21; the second-layer air flow sensor 42 and the second-layer air flow regulating valve 45 are arranged in the second-layer air duct 22. The second-layer air flow sensor 42 monitors the air flow data in the second-layer air duct 22 and transmits the data to the PLC controller. The second-layer air flow regulating valve 45 adjusts the flow cross-section of the air in the second-layer air duct 22 according to the instruction of the PLC controller; the third-layer air flow sensor 43 and the third-layer air flow regulating valve 46 are arranged in the third-layer air duct 23. The third-layer air flow sensor 43 monitors the air flow data in the third-layer air duct 23 and transmits the data to the PLC controller. The third-layer air flow regulating valve 46 adjusts the flow cross-section of the air in the third-layer air duct 23 according to the instruction of the PLC controller.

[0061] The flow regulation execution module of this embodiment is not limited to the regulating valve, and other devices that can control the opening of the air duct can also be used.

[0062] The main process of the present invention using the control system to adjust the air flow of the three-layer air duct of the zinc rectification furnace is as follows:

[0063] First, the set target air flow ratio is input into the PLC controller, the flow monitoring module monitors the real-time air flow data of the three-layer air duct and transmits the data to the PLC controller, the PLC controller obtains the adjustment data of the air flow of the branch air duct according to the real-time air flow data and the target air flow ratio and generates a control instruction at the same time, the PLC controller transmits the control instruction to the flow regulation execution module, the flow regulation execution module receives the control instruction to adjust the flow cross-section of the air in the three-layer air duct, and then adjusts the air flow entering the combustion chamber through the first-layer air duct 21, the second-layer air duct 22 and the third-layer air duct 23, and continuously cycles the entire adjustment process until the real-time air flow ratio of the first-layer air duct 21, the second-layer air duct 22 and the third-layer air duct 23 reaches the target air flow ratio.

[0064] The target air flow ratio is the real-time air flow ratio of the first-layer air duct 21, the second-layer air duct 22 and the third-layer air duct 23, and the target air flow ratio is set to 0.33:0.38:0.29.

[0065] like Figure 3As shown, in order to analyze the distribution law of multi-physical fields in the combustion chamber of the tower zinc distillation furnace, a monitoring section l1 parallel to the east and west surfaces of the combustion chamber is cut in the combustion chamber, and the outer wall of the tower plate is used as the monitoring surface.

[0066] Regarding the influence of the air flow ratio of the three-layer air duct in the embodiment on the air combustion in the combustion chamber, the embodiment performs the following analysis:

[0067] This embodiment uses commercial simulation software to conduct qualitative and quantitative analysis on the combustion chamber operating conditions under different air flow ratios of the three-layer air duct (because the third-layer air duct was not put into use when the actual zinc refiner was put into operation, in order to explore the target air flow ratio of the three-layer air duct, the air flow ratios of the three-layer air duct were set to 0.48:0.52:0, 0.39:0.43:0.18, 0.35:0.40:0.25, 0.33:0.38:0.29, 0.32:0.36:0.32 respectively). At the same time, in order to evaluate the combustion effect of the air at different air flow ratios of the three-layer air duct, the combustion chamber temperature field, the average furnace temperature and the average heat flux density of the tower plate were selected as evaluation indicators.

[0068] Results Analysis

[0069] In order to qualitatively analyze the influence of the third-layer air nozzle on the furnace condition, this section selects the temperature distribution cloud diagram of the combustion chamber l1 section when the air flow ratio of the three-layer air duct is 0.48:0.52:0, 0.39:0.43:0.18, 0.35:0.40:0.25, 0.33:0.38:0.29, and 0.32:0.36:0.32. At the same time, by quantitatively analyzing the key parameters such as the average heat flux density and average temperature of the outer wall of the tower plate, the total reaction heat of the combustion chamber, and the concentration of the flue gas components at the combustion chamber outlet, the influence of the air flow ratio of different three-layer air ducts on the improvement of the furnace condition is judged.

[0070] like Figure 4 As shown in the figure, after the third-layer air duct was put into use, the low-temperature area in the middle and lower part of the combustion chamber was significantly eliminated, and a high-temperature area was formed near the third-layer air nozzle. The overall high-temperature area of ​​the L1 section was also increased. Figure 4 It can be seen that as the proportion of the air flow in the third-layer air duct increases, the low-temperature state at the top of the combustion chamber is significantly improved, and the area of ​​the low-temperature zone gradually decreases as the proportion of the air flow in the third-layer air duct increases, but slightly increases when the proportion of the air flow in the third-layer air duct is 0.32. The increase in the flue gas temperature in the combustion chamber is conducive to the heat transfer of the tower plate wall.

[0071] Figure 5 The temperature distribution cloud diagram of the outer wall of the tower plate when the third-layer air duct has different opening degrees is shown in the figure. Figure 5 It can be seen that the temperature distribution law of the outer wall of the tower plate is similar to that of the l1 section. Opening the third-layer air nozzle significantly improves the temperature distribution of the tower plate. As the proportion of air flow in the third-layer air duct increases, the low-temperature area in the middle and lower part of the tower plate gradually decreases, and the area of ​​the high-temperature area in the middle and upper part gradually increases.

[0072] Figure 6 shows the curve of the average heat flux density and average temperature of the outer wall of the zinc distillation furnace tray with the air flow ratio of the third-layer air duct. As can be seen from the figure, with the increase of the air flow ratio of the third-layer air duct, the average heat flux density and average temperature of the outer wall of the tray first increase and then decrease, and reach the maximum value when the air flow ratio of the third-layer air duct is 0.29. At this time, the average heat flux density of the outer wall of the tray is 47989.14W / m 2 , the average temperature is 1425.97 K. Comprehensive comparison shows that when the air flow rate of the third-layer air duct accounts for 0.29, the temperature field of the outer wall of the tower plate reaches the best.

[0073] Figure 7 The total reaction heat of air combustion in the combustion chamber changes with the increase of air flow rate. As can be seen from the figure, the change law of the total reaction heat of air in the combustion chamber with the increase of air flow rate is similar to the average heat flux density or average temperature of the outer wall of the tower plate. With the increase of the air flow rate of the third-layer air duct, it shows a law of first increasing and then decreasing, and reaches the maximum value when the air flow rate of the third-layer air duct is 0.29. At this time, the total reaction heat of the combustion chamber is 872545.08W.

[0074] In order to further determine the target air flow ratio of the third-layer air duct during the air combustion process in the combustion chamber under the baseline operating parameters, Figure 8 The concentration values ​​of chemical components in the flue gas at the bottom outlet of the combustion chamber under different air flow ratios of the third-layer air duct were counted, taking CH4 and CO as examples. As can be seen from the figure, with the increase of the air flow ratio of the third-layer air duct, the degree of air burnout gradually increases, the CH4 content in the flue gas gradually decreases, and the CO content also gradually decreases. Among them, when the air flow ratio of the third-layer air duct is 0.29, 0.31, and 0.32, the contents of CH4 and CO in the flue gas at the combustion chamber outlet are low and close to each other. From the perspective of flue gas components, the furnace condition is better in the three adjustment conditions of 0.29, 0.31, and 0.32 of the air flow ratio of the third-layer air duct.

[0075] Based on the analysis of the above simulation results, when the air flow ratio of the third-layer air duct is 0.29, the furnace condition of the zinc distillation furnace can reach a better level.

[0076] Furthermore, in order to more accurately obtain the flow data of the above-mentioned pipeline that needs to be monitored and reduce the impact of flow velocity fluctuations in the pipeline, the relative measurement error is used to provide feedback on the sampling times of the flow monitoring module, and the system adjusts the sampling times of the flow monitoring module based on the relative measurement error. The flow measurement cycle can be divided into two stages. The first stage is the relative measurement error calculation stage, which lasts for 2 seconds and has 20 sampling times; the second stage is the sampling times adjustment stage, which lasts for 8 seconds. The sampling times of the second stage are adjusted by the relative measurement error calculated in the first stage. When the relative measurement error exceeds the set threshold, the larger the relative measurement error, the more sampling times the flow monitoring module has. After the sampling times of the second stage are adjusted, the flow data measured in this stage is calculated to obtain the final flow size. The calculation formula for the relative measurement error, the sampling adjustment times, and the final measured flow can be:

[0077] ①Relative measurement error

[0078]

[0079]

[0080]

[0081] The average flow rate measured in the first stage;

[0082] q i : The flow rate of the ith sampling in the 20 samplings in the first stage, q min With q max are the minimum and maximum flow rates in the 20 samplings in the first stage;

[0083] The average error of the first stage measurement;

[0084] q' i : The size of the i-th sampling flow rate in the 18 samplings except the minimum sampling flow rate and the maximum sampling flow rate in the first stage;

[0085] τ c : Relative measurement error.

[0086] ②Sampling adjustment times

[0087]

[0088] τ0: initial relative measurement error, τ0 is 0.05;

[0089] n: sampling adjustment times, which is an integer based on the calculation result. The maximum sampling adjustment times shall not exceed 240 times.

[0090] ③Final measured flow

[0091]

[0092] Final measured flow

[0093] q" i : The size of the i-th sampling flow in the sampling flow except the minimum sampling flow and the maximum sampling flow in the second stage;

[0094] Furthermore, in order to better realize the air flow proportional control of the above three-layer air duct and reduce the control cost at the same time, the proportional scaling rate is used to feedback the control adjustment time. The system determines whether to adjust the flow regulation execution module that controls the air flow ratio based on the size of the proportional scaling rate. When the proportional scaling rate exceeds the set threshold, the control adjustment time is corrected. When the proportional scaling rate is larger, the control adjustment time is shorter. Therefore, the above ratios can be adjusted in time to achieve accurate control. A proportional scaling rate is set for the air flow ratio to achieve the adjustment of the above ratio. The proportional scaling rate of the air flow ratio and the control adjustment time calculation formula can be:

[0095] Q a =1-T a / T a0

[0096]

[0097] T a : Control adjustment time of air flow ratio

[0098] Q a : Scaling ratio of air flow ratio;

[0099] T a0 : Initial adjustment time of air flow ratio, 120 minutes;

[0100] R a12，1 : After the system adjusts the device for controlling the air flow ratio, the PLC controller initially calculates the air flow ratio of the first-layer air duct and the second-layer air duct based on the air flow data monitored by the flow monitoring module. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes;

[0101] R a23，1: After the system adjusts the device for controlling the air flow ratio, the PLC controller initially calculates the air flow ratio of the second-layer air duct and the third-layer air duct based on the air flow data monitored by the flow monitoring module. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes;

[0102] R a12，2 : Before the system adjusts the air flow ratio, the air flow ratio of the first-layer air duct and the second-layer air duct is calculated by the PLC controller for the air flow data monitored by the flow monitoring module for the last time. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module every 20 minutes;

[0103] R a23，2 : Before the system adjusts the air flow ratio, the PLC controller calculates the air flow ratio of the second-layer air duct and the third-layer air duct based on the air flow data monitored by the flow monitoring module for the last time. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes.

[0104] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

Claims

1. A three-layer air duct flow optimization control system for a zinc distillation furnace, the zinc distillation furnace includes a combustion chamber and an air duct, characterized in that: It includes a flow monitoring module, a flow control module and a flow regulation execution module. The flow monitoring module and the flow regulation execution module are respectively connected to the flow control module. The flow control module has a built-in target air flow ratio. The flow monitoring module and the flow regulation execution module are arranged in the air duct. The flow monitoring module monitors the air flow in the air duct and transmits the real-time air flow data to the flow control module. The flow control module obtains the real-time air flow ratio according to the real-time air flow data, and obtains the air flow adjustment data according to the real-time air flow ratio and the target air flow ratio. The flow control module outputs a control instruction to the flow regulation execution module, and the flow regulation execution module adjusts the air flow in the air duct according to the control instruction.

2. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 1 is characterized in that: The flow control module adopts a PLC controller, the air duct includes a branch air duct, the branch air duct is a three-layer air duct structure, the flow monitoring module is arranged in the branch air duct, and is used to monitor the air flow in the branch air duct, and the flow regulation execution module is arranged in the branch air duct, and is used to regulate the air flow in the air duct.

3. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 2 is characterized in that: The branch air duct includes a first-layer air duct, a second-layer air duct and a third-layer air duct, the flow monitoring module includes a first-layer air flow sensor, a second-layer air flow sensor and a third-layer air flow sensor, and the flow regulation execution module includes a first-layer air flow regulating valve, a second-layer air flow regulating valve and a third-layer air flow regulating valve.

4. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 3 is characterized in that: The first layer air flow sensor and the first layer air flow regulating valve are arranged at The first-layer air duct, the first-layer air flow sensor monitors the air flow data in the first-layer air duct and transmits the data to the PLC controller, and the first-layer air flow regulating valve adjusts the flow cross-section of the air in the first-layer air duct according to the instruction of the PLC controller; the second-layer air flow sensor and the second-layer air flow regulating valve are arranged in the second-layer air duct, the second-layer air flow sensor monitors the air flow data in the second-layer air duct and transmits the data to the PLC controller, and the second-layer air flow regulating valve adjusts the flow cross-section of the air in the second-layer air duct according to the instruction of the PLC controller; the third-layer air flow sensor and the third-layer air flow regulating valve are arranged in the third-layer air duct, the third-layer air flow sensor monitors the air flow data in the third-layer air duct and transmits the data to the PLC controller, and the third-layer air flow regulating valve adjusts the flow cross-section of the air in the third-layer air duct according to the instruction of the PLC controller.

5. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 3 is characterized in that: The target air flow ratio is the real-time air flow ratio of the first-layer air duct, the second-layer air duct and the third-layer air duct, and the target air flow ratio is set to 0.33:0.38:0.

29.

6. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 1, characterized in that: The sampling times of the flow monitoring module are fed back through the relative measurement error. The flow measurement cycle is divided into two stages. The first stage is the relative measurement error calculation stage, and the second stage is the sampling times adjustment stage. The sampling times of the second stage are adjusted by the relative measurement error calculated in the first stage. After the sampling times adjustment of the second stage is completed, the flow data measured in this stage are calculated to obtain the final flow size.

7. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 6, characterized in that: The calculation formula of the relative measurement error is: The average flow rate measured in the first stage; q i : The flow rate of the ith sampling in the 20 samplings in the first stage, q min With q max are the minimum and maximum flow rates in the 20 samplings in the first stage; The average error of the first stage measurement; q' i : The size of the i-th sampling flow rate in the 18 samplings except the minimum sampling flow rate and the maximum sampling flow rate in the first stage; τ c : Relative measurement error.

8. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 6, Features: The calculation formula for the sampling adjustment times is: τ0: initial relative measurement error, τ0 is 0.05; n: sampling adjustment times, which is an integer based on the calculation result. The maximum sampling adjustment times shall not exceed 240 times.

9. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 6, Features: The calculation formula of the final measured flow rate is: The final measured flow rate; q" i : The size of the i-th sampling flow in the sampling flow except the minimum sampling flow and the maximum sampling flow in the second stage.

10. The three-layer air duct flow optimization control system of a zinc rectification furnace according to claim 1, characterized in that: The air flow ratio control uses the ratio scaling rate to provide feedback on the control adjustment time. The air flow ratio scaling rate and the control adjustment time calculation formula are: Q a =1-T a / T a0 T a : Control adjustment time of air flow ratio Q a : Scaling ratio of air flow ratio; T a0 : Initial adjustment time of air flow ratio, 120 minutes; R a12，1 : After the system adjusts the device for controlling the air flow ratio, the PLC controller initially calculates the air flow ratio of the first-layer air duct and the second-layer air duct based on the air flow data monitored by the flow monitoring module. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes; R a23，1 : After the system adjusts the device for controlling the air flow ratio, the PLC controller initially calculates the air flow ratio of the second-layer air duct and the third-layer air duct based on the air flow data monitored by the flow monitoring module. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes; R a12，2 : Before the system adjusts the air flow ratio, the air flow ratio of the first-layer air duct and the second-layer air duct is calculated by the PLC controller for the air flow data monitored by the flow monitoring module for the last time. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module every 20 minutes; R a23，2 : Before the system adjusts the air flow ratio, the PLC controller calculates the air flow ratio of the second-layer air duct and the third-layer air duct based on the air flow data monitored by the flow monitoring module for the last time. During the control adjustment time, the PLC controller calculates the air-fuel ratio of the air flow data monitored by the flow monitoring module once every 20 minutes.

Images