Boiler blow-down water waste heat recovery control method, system, equipment and medium

Abstract

The invention discloses a boiler blow-down water waste heat recovery control method, system and equipment and a medium. The method comprises the following steps that the current waste heat recovery efficiency eta of a waste heat recovery system is obtained; the current scaling coefficient R of a heat exchanger in the waste heat recovery system is obtained; according to the current waste heat recovery efficiency eta and the current scaling coefficient R, the heat transfer coefficient K of the heat exchanger is obtained; the current temperature T and the water quality concentration ratio C of the boiler are obtained; and inputting the heat transfer coefficient K, the current temperature T and the water quality concentration ratio C into a preset discharge capacity optimization model to obtain the optimal discharge capacity Q. The method has the advantages that the discharge capacity can be adaptively adjusted, and the boiler safety and waste heat recovery requirements can be balanced.

Description

Technical Field

[0001] This application relates to the field of coal-fired power technology, and in particular to a method, system, equipment and medium for controlling waste heat recovery from boiler blowdown. Background Technology

[0002] In recent years, the installed capacity of new energy sources such as wind power, photovoltaics, and hydropower has grown rapidly. However, the instability of these new energy sources has brought challenges to power supply and security. Therefore, the coal-fired power industry is promoting the implementation of "three-pronged reforms"—energy conservation and emission reduction, heating system upgrades, and flexibility upgrades—while strictly controlling coal-fired power projects, continuously optimizing the energy and power structure and layout, and deeply promoting the clean, efficient, flexible, low-carbon, and intelligent high-quality development of coal-fired power. In order to achieve the goals of the coal-fired power industry, energy conservation, heating, and flexibility are key issues that coal-fired power units should comprehensively consider.

[0003] Currently, boiler equipment is generally equipped with a waste heat recovery system to recover and utilize the waste heat from high-temperature wastewater. However, existing waste heat recovery systems lack an effective monitoring mechanism. The discharge volume of high-temperature wastewater is basically operated at a fixed flow rate. If the discharge volume exceeds the system's processing capacity, the unrecovered high-temperature wastewater is directly discharged, resulting in low waste heat utilization. At the same time, the continuous high discharge volume will accelerate the concentration cycle and increase the risk of scaling. If the discharge volume is insufficient, the concentration of impurities in the boiler water will continue to rise, thereby triggering a series of boiler safety risks. Therefore, a monitoring and control system that can adaptively adjust the discharge volume according to the operation of the waste heat recovery system is needed. Summary of the Invention

[0004] The main purpose of this application is to provide a method, system, equipment and medium for controlling waste heat recovery from boiler blowdown, which aims to solve the technical problem that existing waste heat recovery systems lack a monitoring mechanism and are difficult to adaptively adjust the amount of wastewater discharged according to the system operation.

[0005] To achieve the above objectives, this application provides a method for controlling waste heat recovery from boiler blowdown, comprising the following steps: Obtain the current waste heat recovery efficiency η of the waste heat recovery system; Obtain the current fouling coefficient R of the heat exchanger in the waste heat recovery system; The heat transfer coefficient K of the heat exchanger is obtained based on the current waste heat recovery efficiency η and the current fouling coefficient R. Obtain the current boiler temperature T and water concentration ratio C; Input the heat transfer coefficient K, the current temperature T, and the water concentration ratio C into the preset sewage discharge optimization model to obtain the optimal sewage discharge amount Q.

[0006] Optionally, the expression for the wastewater discharge optimization model is: Q = K(T-T0) / lnC; In the formula, T0 is the safe temperature threshold, and C=C max / C min C max C represents the current total dissolved solids concentration in the boiler water. min The minimum permissible concentration of dissolved solids.

[0007] Optionally, obtaining the current waste heat recovery efficiency η of the waste heat recovery system includes: Obtain the theoretical recoverable heat E1 of the waste heat recovery system per unit time; Obtain the actual heat recovery E2 of the waste heat recovery system per unit time; Based on the theoretical recoverable heat E1 and the actual recovered heat E2, the current waste heat recovery efficiency η is obtained; where η = E2 / E1.

[0008] Optionally, the expression for the theoretically recoverable heat E1 is: E1=L·ρ·c p ·(T1 T')·(1 R); In the formula, L is the sewage flow rate per unit time, ρ is the sewage density, and c p T1 is the specific heat capacity of the wastewater, T2 is the temperature of the wastewater when it passes through the inlet of the heat exchanger, and T' is the reference temperature.

[0009] Optionally, the expression for the current scaling factor R is: R=ε·σ / σ max ·t; In the formula, ε is the material fouling rate constant of the heat exchanger, σ is the real-time conductivity of the heat exchanger, and σ max t is the electrical conductivity threshold of the heat exchanger, and t is the continuous operating time of the heat exchanger.

[0010] Optionally, obtaining the heat transfer coefficient K of the heat exchanger based on the current waste heat recovery efficiency η and the current scaling factor R includes: Based on the current waste heat recovery efficiency η, obtain the first heat transfer coefficient K1 of the heat exchanger; where K1 = 0.8K0·η, and K0 is the reference heat transfer coefficient; Based on the current fouling coefficient R, obtain the second heat transfer coefficient K2 of the heat exchanger; where K2 = K0·(1-R) 1.5 ; The heat transfer coefficient K of the heat exchanger is obtained based on the first heat transfer coefficient K1 and the second heat transfer coefficient K2; where K = (K1 + K2) / 2.

[0011] Optionally, after inputting the heat transfer coefficient K, the current temperature T, the safe temperature threshold T0, and the water concentration ratio C into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q, the method further includes: Obtain the total recovered heat energy E from the heat exchanger; where E = η·c p ·(T1 T2), c p T1 is the specific heat capacity of the wastewater, T2 is the temperature of the wastewater when it passes through the inlet of the heat exchanger, and T2 is the temperature of the wastewater when it passes through the outlet of the heat exchanger. Obtain the ratio coefficient U; where U = E / Q; Determine whether the ratio coefficient U is less than the preset balance threshold. If so, reduce the optimal sewage discharge amount Q so that the ratio coefficient U is greater than the balance threshold.

[0012] To achieve the above objectives, this application discloses a boiler blowdown waste heat recovery control system, comprising: The waste heat recovery efficiency calculation module is used to obtain the current waste heat recovery efficiency η of the waste heat recovery system; The fouling coefficient calculation module is used to obtain the current fouling coefficient R of the heat exchanger in the waste heat recovery system; The heat transfer coefficient calculation module is used to obtain the heat transfer coefficient K of the heat exchanger based on the current waste heat recovery efficiency η and the current fouling coefficient R. The parameter acquisition module is used to obtain the boiler's current temperature T and water concentration ratio C; The wastewater discharge optimization module is used to input the heat transfer coefficient K, the current temperature T, and the water concentration ratio C into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q.

[0013] To achieve the above objectives, this application also provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the above-described method.

[0014] To achieve the above objectives, this application also provides a computer-readable storage medium storing a computer program, on which a processor executes the computer program to implement the above-described method.

[0015] The beneficial effects that this application can achieve are as follows: This application monitors the current waste heat recovery efficiency η and the current scaling coefficient R of the heat exchanger in real time. By combining the waste heat recovery efficiency η and the current scaling coefficient R, the heat transfer coefficient K of the heat exchanger can be accurately estimated. At the same time, the current temperature T of the boiler and the water concentration ratio C are monitored and collected. The above parameters have different degrees of influence on the operational safety and waste heat utilization rate of the waste heat recovery system. Therefore, after inputting the above parameters into the preset wastewater discharge optimization model, the optimal wastewater discharge Q can be accurately obtained. When any of the above parameters changes, the optimal wastewater discharge Q can be adaptively adjusted, thereby effectively guiding the wastewater discharge control of the waste heat recovery system, thus achieving the goal of balancing system operational safety and waste heat utilization rate. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0017] Figure 1 This is a schematic flowchart of a boiler wastewater waste heat recovery control method according to an embodiment of this application; Figure 2 This is a schematic diagram of the framework of a boiler wastewater waste heat recovery control system according to an embodiment of this application; Figure 3 This is a schematic diagram of the computer device structure of the hardware operating environment involved in the embodiments of this application.

[0018] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] It should be noted that if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0021] Example 1 Reference Figure 1 This embodiment provides a method for controlling waste heat recovery from boiler blowdown, including the following steps: Obtain the current waste heat recovery efficiency η of the waste heat recovery system; Obtain the current fouling coefficient R of the heat exchanger in the waste heat recovery system; The heat transfer coefficient K of the heat exchanger is obtained based on the current waste heat recovery efficiency η and the current fouling coefficient R. Obtain the current boiler temperature T and water concentration ratio C; Input the heat transfer coefficient K, the current temperature T, and the water concentration ratio C into the preset sewage discharge optimization model to obtain the optimal sewage discharge amount Q.

[0022] In this embodiment, by real-time monitoring of the current waste heat recovery efficiency η and the current scaling coefficient R of the heat exchanger, the heat transfer coefficient K of the heat exchanger can be accurately estimated by combining the waste heat recovery efficiency η and the current scaling coefficient R. Simultaneously, the current boiler temperature T and water concentration ratio C are monitored and collected. These parameters all have varying degrees of impact on the operational safety and waste heat utilization rate of the waste heat recovery system. Therefore, by inputting these parameters into a preset wastewater discharge optimization model, the optimal wastewater discharge rate Q can be accurately obtained. Here, the optimal wastewater discharge rate Q is the unit time (usually m... 3 The amount of wastewater to be discharged ( / h) can be used to balance boiler safety and waste heat recovery needs. When any of the above parameters changes, the optimal discharge volume Q can be adaptively adjusted, thereby effectively guiding the discharge volume control of the waste heat recovery system, thus achieving the goal of balancing system operation safety and waste heat utilization.

[0023] As an optional implementation, the expression for the wastewater discharge optimization model is: Q = K(T-T0) / lnC; In the formula, T0 is the safe temperature threshold, and C=C max / C min C max C represents the current total dissolved solids concentration in the boiler water. min The minimum permissible concentration of dissolved solids.

[0024] In this embodiment, the heat transfer coefficient K can reflect the comprehensive parameter of the heat transfer capacity of the heat exchanger. The safe temperature threshold T0 is set to reduce the risk of scaling. Therefore, the value of K(T-T0) here can characterize the available heat driving force, that is, allow a larger amount of wastewater discharge when the temperature difference is high. lnC reflects the degree of water quality deterioration. The worse the water quality, the nonlinear increase in the wastewater discharge demand. The heat transfer coefficient K and the water concentration ratio C can jointly determine the wastewater discharge efficiency, that is, a high K value can partially offset the effect of high concentration. Therefore, based on the above formula, the optimal wastewater discharge Q with strong guidance and reference can be calculated.

[0025] For example, the current temperature of a coal-fired boiler is measured to be T=380℃, let T0=360℃, and C is measured. max =5000ppm, C min =1500ppm, and K was calculated to be 120W / (m 2Substituting k into the above formula, we can calculate Q = 120(380-360) / ln(5000 / 1500) = 2000m 3 / h.

[0026] As an optional implementation, obtaining the current waste heat recovery efficiency η of the waste heat recovery system includes: Obtain the theoretical recoverable heat E1 of the waste heat recovery system per unit time; Obtain the actual heat recovery E2 of the waste heat recovery system per unit time; Based on the theoretical recoverable heat E1 and the actual recovered heat E2, the current waste heat recovery efficiency η is obtained; where η = E2 / E1.

[0027] In this embodiment, the theoretical recoverable heat E1 and the actual recovered heat E2 of the waste heat recovery system per unit time are calculated in real time. The current waste heat recovery efficiency η = E2 / E1 can then be calculated. The theoretical recoverable heat E1 and the actual recovered heat E2 need to be calculated and updated every unit time (e.g., 10 minutes, 20 minutes or 30 minutes) to update the current waste heat recovery efficiency η, so as to ensure the timeliness of the data and improve the adaptive adjustment capability of subsequent sewage discharge.

[0028] As an optional implementation method, the expression for the theoretically recoverable heat E1 is: E1=L·ρ·c p ·(T1 T')·(1 R); In the formula, L is the sewage flow rate per unit time, ρ is the sewage density, and c p T1 is the specific heat capacity of the wastewater, T2 is the temperature of the wastewater when it passes through the inlet of the heat exchanger, and T' is the reference temperature.

[0029] In this embodiment, the theoretical recoverable heat E1 in the above formula is calculated based on the basic principle of mass × specific heat capacity × temperature difference. At the same time, the influence of the current scaling coefficient R on the heat transfer efficiency loss is also introduced. The scaling layer increases the thermal resistance and reduces the effective heat transfer. That is, the larger the R value, the higher the proportion of heat transfer efficiency loss due to scaling, and the smaller the theoretical recoverable heat E1. Thus, the theoretical recoverable heat E1 of the waste heat recovery system can be accurately estimated.

[0030] It should be noted that in the above formula, the sewage flow rate L can be monitored in real time by a flow sensor, and the sewage density ρ is usually taken as 1000 kg / m³. 3 (Room temperature clean water) If it is high-salt and alkaline wastewater, it needs to be adjusted. The specific heat capacity of the wastewater is c. pThe standard value is 4.18 kJ / (kg·℃). However, actual measurement is required when impurities are present. Temperature T1 can be measured using a temperature sensor located at the heat exchanger inlet. The reference temperature T' is typically the ambient temperature or the initial temperature of the makeup water. (T1) T') can reflect the actual temperature drop potential of wastewater.

[0031] As an optional implementation, the current expression for the scaling factor R is: R=ε·σ / σ max ·t; In the formula, ε is the material fouling rate constant of the heat exchanger, σ is the real-time conductivity of the heat exchanger, and σ max t is the electrical conductivity threshold of the heat exchanger, and t is the continuous operating time of the heat exchanger.

[0032] In this embodiment, the material scaling rate constant ε can be determined experimentally, i.e., it is used to characterize the scaling rate. Therefore, the larger the value of ε, the larger the current scaling coefficient R will be, and σ / σ max It can reflect the real-time impact of wastewater salinity or impurity content on scaling risk, and the real-time conductivity σ is related to the concentration of ions in the water (such as Ca). 2+ Mg 2+ CO3 2+ The above three parameters are positively correlated and directly characterize the salt, alkali or impurity content of wastewater. The longer the continuous operation time t, the greater the degree of scaling. Therefore, the above three parameters can jointly characterize the degree of influence on the current scaling coefficient R, and the calculation is accurate and reliable.

[0033] It should be noted that when the current scaling coefficient R is detected to be greater than the preset scaling coefficient threshold or σ / σ max An alarm can be triggered when the temperature exceeds 1 or the continuous operating time t reaches the time threshold, reminding staff to clean the scale buildup on the heat exchanger in a timely manner.

[0034] As an optional implementation, obtaining the heat transfer coefficient K of the heat exchanger based on the current waste heat recovery efficiency η and the current scaling factor R includes: Based on the current waste heat recovery efficiency η, obtain the first heat transfer coefficient K1 of the heat exchanger; where K1 = 0.8K0·η, and K0 is the reference heat transfer coefficient; Based on the current fouling coefficient R, obtain the second heat transfer coefficient K2 of the heat exchanger; where K2 = K0·(1-R) 1.5 ; The heat transfer coefficient K of the heat exchanger is obtained based on the first heat transfer coefficient K1 and the second heat transfer coefficient K2; where K = (K1 + K2) / 2.

[0035] In this embodiment, since the heat transfer coefficient K reflects the comprehensive parameter of the heat exchanger's heat transfer capacity, the magnitude of the waste heat recovery efficiency is a direct reflection of the heat transfer coefficient K. Therefore, the current waste heat recovery efficiency η is calculated here, and the first heat transfer coefficient K1 of the heat exchanger can be calculated based on the empirical formula K1=0.8K0·η (where 0.8 is an empirical coefficient). The heat transfer coefficient is then corrected in a closed-loop manner based on the current waste heat recovery efficiency η. For example, if η=90% and K0=160, then K1=0.8*160*0.9=115.2. Simultaneously, considering the influence of the fouling coefficient on the heat transfer coefficient, the empirical formula K2=K0·(1-R) ​​is also used. 1.5 The second heat transfer coefficient K2 is calculated. For example, if the current scaling factor R is calculated to be 0.2, then K2 = 160 * (1 - 0.2). 1.5 =114.5. The final heat transfer coefficient K is calculated as the average of the first heat transfer coefficient K1 and the second heat transfer coefficient K2, that is, K=115.2+114.5=114.85. Therefore, the heat transfer coefficient K here combines the feedback correction of waste heat recovery efficiency and the direct influence of the scaling coefficient, and the calculation result is more accurate and reliable.

[0036] As an optional implementation, after inputting the heat transfer coefficient K, the current temperature T, the safe temperature threshold T0, and the water concentration ratio C into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q, the method further includes: Obtain the total recovered heat energy E from the heat exchanger; where E = η·c p ·(T1 T2), c p T1 is the specific heat capacity of the wastewater, T2 is the temperature of the wastewater when it passes through the inlet of the heat exchanger, and T2 is the temperature of the wastewater when it passes through the outlet of the heat exchanger. Obtain the ratio coefficient U; where U = E / Q; Determine whether the ratio coefficient U is less than the preset balance threshold. If so, reduce the optimal sewage discharge amount Q so that the ratio coefficient U is greater than the balance threshold.

[0037] In this embodiment, since the system may employ multi-stage heat exchangers, taking a three-stage heat exchanger as an example, the current waste heat recovery efficiencies of each stage heat exchanger are η1, η2, and η3, respectively, (T1 T2) represents the temperature difference ΔT between the inlet and outlet of the heat exchanger, which directly reflects the heat potential extracted from the wastewater by that stage of the heat exchanger. Let each stage of the heat exchanger be ΔT1, ΔT2, and ΔT3. The total recovered heat energy E per unit time can be calculated using the above formula: E = η1·c p ·ΔT1+η2c p ·ΔT2+η3·c p·ΔT3, and then link it with the currently calculated optimal wastewater discharge amount Q to obtain the ratio coefficient U. This ratio coefficient U can characterize the balance coefficient between the recovered heat energy and the wastewater discharge amount of the entire waste heat recovery system. If the ratio coefficient U is less than the preset balance threshold, it indicates that the system is prone to imbalance leading to safety issues such as overload. At this time, the optimal wastewater discharge amount Q can be further corrected based on the ratio coefficient U to improve the balance performance of the optimal wastewater discharge amount Q for the entire waste heat recovery system.

[0038] Example 2 Based on the same inventive concept as the foregoing embodiments, and referring to... Figure 2 This embodiment provides a boiler wastewater waste heat recovery control system, including: The waste heat recovery efficiency calculation module is used to obtain the current waste heat recovery efficiency η of the waste heat recovery system; The fouling coefficient calculation module is used to obtain the current fouling coefficient R of the heat exchanger in the waste heat recovery system; The heat transfer coefficient calculation module is used to obtain the heat transfer coefficient K of the heat exchanger based on the current waste heat recovery efficiency η and the current fouling coefficient R. The parameter acquisition module is used to obtain the boiler's current temperature T and water concentration ratio C; The wastewater discharge optimization module is used to input the heat transfer coefficient K, the current temperature T, and the water concentration ratio C into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q. The explanations and examples of the modules in this embodiment can be found in the methods of the foregoing embodiments, and will not be repeated here.

[0039] Example 3 Based on the same inventive concept as the foregoing embodiments, this embodiment provides a computer device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method.

[0040] As an optional implementation method, refer to Figure 3 , Figure 3This is a schematic diagram of the computer device structure of the hardware operating environment involved in this embodiment. The computer device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to realize communication between these components. The user interface 1003 may include a display screen and an input unit such as a keyboard. Optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk storage device. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0041] Those skilled in the art will understand that Figure 3 The structure shown does not constitute a limitation on the computer device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0042] like Figure 3 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a data storage module, a network communication module, a user interface module, and electronic programs.

[0043] exist Figure 3 In the computer device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the computer device of this embodiment can be set in the computer device. The computer device calls the boiler wastewater waste heat recovery control system stored in the memory 1005 through the processor 1001 and executes the boiler wastewater waste heat recovery control method provided in the above embodiment.

[0044] Example 4 Based on the same inventive concept as the foregoing embodiments, this embodiment provides a computer-readable storage medium storing a computer program, and a processor executes the computer program to implement the above-described method.

[0045] In some embodiments, the computer-readable storage medium may be a memory such as FRAM, ROM, PROM, EPROM, EEPROM, flash memory, magnetic surface memory, optical disk, or CD-ROM; or it may be a variety of devices including one or any combination of the above-mentioned memories.

[0046] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for controlling waste heat recovery from boiler blowdown, characterized in that, Includes the following steps: Obtain the current waste heat recovery efficiency η of the waste heat recovery system; Obtain the current fouling coefficient R of the heat exchanger in the waste heat recovery system; The heat transfer coefficient K of the heat exchanger is obtained based on the current waste heat recovery efficiency η and the current scaling coefficient R. Obtain the current boiler temperature T and water concentration ratio C; The heat transfer coefficient K, the current temperature T, and the water concentration ratio C are input into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q.

2. The method for controlling waste heat recovery from boiler blowdown as described in claim 1, characterized in that, The expression for the wastewater discharge optimization model is: Q = K(T-T0) / lnC; In the formula, T0 is the safe temperature threshold, and C = C max / C min C max C represents the current total dissolved solids concentration in the boiler water. min The minimum permissible concentration of dissolved solids.

3. The method for controlling waste heat recovery from boiler blowdown as described in claim 1, characterized in that, The process of obtaining the current waste heat recovery efficiency η of the waste heat recovery system includes: Obtain the theoretical recoverable heat E1 of the waste heat recovery system per unit time; Obtain the actual heat recovery E2 of the waste heat recovery system per unit time; Based on the theoretically recoverable heat E1 and the actual recovered heat E2, the current waste heat recovery efficiency η is obtained; where η = E2 / E1.

4. The boiler wastewater waste heat recovery control method as described in claim 3, characterized in that, The expression for the theoretically recoverable heat E1 is: E1=L·ρ·c p ·(T1 T')·(1 R); In the formula, L is the sewage flow rate per unit time, ρ is the sewage density, and c p T1 is the specific heat capacity of the wastewater, T2 is the temperature of the wastewater when it passes through the inlet of the heat exchanger, and T' is the reference temperature.

5. A method for controlling waste heat recovery from boiler blowdown as described in any one of claims 1-4, characterized in that, The expression for the current scaling factor R is: R=e·s / s max ·t; In the formula, ε is the material fouling rate constant of the heat exchanger, σ is the real-time conductivity of the heat exchanger, and σ max t is the electrical conductivity threshold of the heat exchanger, and t is the continuous operating time of the heat exchanger.

6. The method for controlling waste heat recovery from boiler blowdown as described in claim 1, characterized in that, The step of obtaining the heat transfer coefficient K of the heat exchanger based on the current waste heat recovery efficiency η and the current scaling coefficient R includes: Based on the current waste heat recovery efficiency η, the first heat transfer coefficient K1 of the heat exchanger is obtained; where K1 = 0.8K0·η, and K0 is the reference heat transfer coefficient; Based on the current fouling coefficient R, obtain the second heat transfer coefficient K2 of the heat exchanger; where K2 = K0·(1-R). 1.5 ; The heat transfer coefficient K of the heat exchanger is obtained based on the first heat transfer coefficient K1 and the second heat transfer coefficient K2; where K = (K1 + K2) / 2.

7. The method for controlling waste heat recovery from boiler blowdown as described in claim 1, characterized in that, After inputting the heat transfer coefficient K, the current temperature T, and the water concentration ratio C into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q, the process further includes: Obtain the total recovered heat energy E from the heat exchanger; where E = η·c p ·(T1 T2), c p T1 is the specific heat capacity of the wastewater, T2 is the temperature of the wastewater when it passes through the inlet of the heat exchanger, and T2 is the temperature of the wastewater when it passes through the outlet of the heat exchanger. Obtain the ratio coefficient U; where U = E / Q; Determine whether the ratio coefficient U is less than a preset balance threshold. If so, reduce the optimal sewage discharge amount Q so that the ratio coefficient U is greater than the balance threshold.

8. A boiler wastewater waste heat recovery control system, characterized in that, include: The waste heat recovery efficiency calculation module is used to obtain the current waste heat recovery efficiency η of the waste heat recovery system; The fouling coefficient calculation module is used to obtain the current fouling coefficient R of the heat exchanger in the waste heat recovery system; The heat transfer coefficient calculation module is used to obtain the heat transfer coefficient K of the heat exchanger based on the current waste heat recovery efficiency η and the current fouling coefficient R. The parameter acquisition module is used to obtain the boiler's current temperature T and water concentration ratio C; The wastewater discharge optimization module is used to input the heat transfer coefficient K, the current temperature T, and the water concentration ratio C into a preset wastewater discharge optimization model to obtain the optimal wastewater discharge amount Q.

9. A computer device, characterized in that, The computer device includes a memory and a processor, wherein the memory stores a computer program and the processor executes the computer program to implement the method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and the processor executes the computer program to implement the method as described in any one of claims 1-7.

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