A method and device for recovering heat energy of high-temperature flue gas from a metallurgical furnace

Abstract

The present invention relates to the technical field of heat energy recovery of metallurgical furnaces, and discloses a method and device for recycling heat energy of high-temperature flue gas of metallurgical furnaces. The method comprises that the high-temperature flue gas discharged from the furnace enters a waste heat boiler arranged with a boiler tube connected to an upstream water pump, and under the heating of the high-temperature flue gas, the water in the boiler tube forms superheated steam, and the superheated steam is introduced into the preheater by the pipeline for heating the low-temperature gas-phase feed; the upstream of the low-temperature gas-phase feed is connected to a compressor, and the downstream is connected to a spray gun, and is directly sprayed into the furnace after preheating, and the high-temperature steam at this time is used to drive the downstream generator to generate electricity, and is converted into liquid after the heat energy is released by the power generation; finally, it flows back into the water tank and is pumped into the waste heat boiler again by the water pump to form a cycle. The system comprises a compressor, an air preheater, a waste heat boiler, a generator, a pump, a metallurgical furnace, a spray gun and a boiler tube. The present invention can increase the initial temperature of the furnace intake, reduce fuel consumption, accelerate the melting speed of materials, and improve smelting efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of heat energy recovery of metallurgical furnaces, and in particular to a method and device for recovering heat energy of high-temperature flue gas of metallurgical furnaces. Background Art

[0002] Metal smelting is the process of changing metal from a combined state to a free state. The commonly used method is to use reducing agents such as carbon, carbon monoxide, and hydrogen to react with metal oxides at high temperatures to obtain metal elements. In the process of metal smelting using various furnaces, a large amount of high-temperature flue gas will be generated, and its heat accounts for 30% to 50% of the total heat entering the furnace. With the development of the smelting industry, most of the new metallurgical furnaces are equipped with waste heat boilers. The basic principle is to recover the heat energy of high-temperature flue gas and generate superheated steam for power generation. Although this method recovers the heat energy of high-temperature flue gas to a certain extent, it also has certain limitations. The heat energy carried by the high-temperature flue gas is not reused by the furnace, and the smelting efficiency cannot be improved by this. The conversion efficiency of heat energy to electric energy is relatively low when using high-temperature flue gas to generate superheated steam for power generation. In the smelting process, a large amount of gas, such as air, oxygen-enriched air, and methane, is usually introduced into the furnace, and the heating of these normal temperature gases consumes a lot of energy. Therefore, the existing technology needs to be improved.

[0003] Prior art 1, application number: CN202310135074.5 discloses an integrated system for heat recovery and flue gas purification of a waste heat boiler, which relates to the technical field of waste heat boilers; it includes a dust removal box, one side of the dust removal box is connected to a heat recovery box, an evaporator tube is provided in the heat recovery box, and openings at both ends of the evaporator tube extend out of the heat recovery box, and a barrier net and a replacement net are set up in the dust removal box, and the barrier net and the replacement net are both arranged along the width direction of the dust removal box, the barrier net includes a plurality of mounting rods and a plurality of barrier plates, and the plurality of mounting rods are vertically arranged and evenly arranged along the width direction of the dust removal box, the mounting rods can be moved horizontally in the dust removal box, the barrier plates correspond to the mounting rods one by one and are fixedly connected to the mounting rods, the replacement net includes a plurality of replacement rods and replacement plates, the replacement rods are parallel to the mounting rods and are staggered with the mounting rods, the replacement rods can be moved horizontally in the dust removal box, the replacement plates correspond to the replacement rods one by one and are fixedly connected to the replacement rods. Although the heat recovery of the waste heat boiler is achieved and there is no need to open the dust box for dust cleaning in the short term, which improves work efficiency, the heating of a large amount of room temperature gas introduced into the kiln consumes a lot of energy and increases production costs.

[0004] Prior art 2, application number: CN202311456023.9 ​​discloses a boiler waste heat recovery device and recovery method; by connecting a sensor, a thermal motor and a battery at the boiler output, the start and stop of the thermal motor can be controlled according to the temperature and air pressure of the steam, and the thermal energy of the high-temperature and high-pressure steam is converted into the mechanical energy of the thermal motor and then converted into the electrical energy storage of the battery, thereby achieving the effect of boiler waste heat recovery and conversion into electrical energy, even when there is only a small amount of steam, it can be transmitted through a pipeline by the thermal motor, thereby improving the effect of waste heat recovery, by adding an adaptive PID control program to the PLC controller without changing the original boiler control system, the deaerator pump and the high-temperature return water pump can be adaptively regulated, so that the boiler deaerator and the heat exchanger can automatically control the water level, and the boiler deaerator and the heat exchanger obtain a stable water level, ensuring that the water level is stable within a reasonable range, ensuring the continuous and stable operation of the gas boiler and the waste heat recovery system, and exerting the best efficiency of the waste heat recovery system. Although the thermal energy of the high-temperature and high-pressure steam is converted into the mechanical energy of the thermal motor and then converted into the electrical energy storage of the battery, the effect of boiler waste heat recovery and conversion into electrical energy is achieved. However, the conversion efficiency of heat energy to electric energy is relatively low when using high-temperature flue gas to generate superheated steam for power generation.

[0005] Prior art three, application number: CN202011233121.2 discloses a steam generating device for recovering waste heat from low-temperature tail gas, which belongs to the field of steam utilization technology in thermal energy engineering, including a heat pump circulation heating system for heating soft water, a high-pressure delivery atomization system for delivering high-pressure soft water thereto, and a waste heat recovery system for recovering waste heat from low-temperature tail gas and delivering heat to the heat pump circulation system. Although it solves the technical problem that the low-temperature tail gas of the furnace is not fully utilized at present, it also solves the problem of slow gas production rate of direct evaporation. However, the heat energy carried by the high-temperature flue gas is not reused by the furnace, and the smelting efficiency cannot be improved by this.

[0006] At present, the existing technologies 1, 2 and 3 have the following problems: the heat energy carried by the high-temperature flue gas is not reused by the furnace, and the smelting efficiency cannot be improved by this; the conversion efficiency of heat energy to electric energy is relatively low when high-temperature flue gas is used to generate superheated steam for power generation; and during the smelting process, normal-temperature gas is introduced into the furnace, and the heating of the normal-temperature gas consumes a lot of energy. Therefore, the present invention provides a method and device for preheating gas phase injection using the waste heat of high-temperature flue gas from a metallurgical furnace, so as to increase the initial temperature of the furnace intake air, improve the combustion efficiency, accelerate the melting speed of materials, and improve the smelting efficiency. Summary of the invention

[0007] The main purpose of the present invention is to provide a method and device for recovering and utilizing heat energy of high-temperature flue gas of a metallurgical furnace, so as to solve the problems in the prior art that the heat energy carried by the high-temperature flue gas is not reused by the furnace, resulting in low smelting efficiency; the conversion efficiency of heat energy to electric energy is relatively low when high-temperature flue gas is used to generate superheated steam for power generation; and the heating of normal-temperature gas introduced into the furnace during the smelting process consumes a large amount of energy.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A method for recovering heat energy from high-temperature flue gas of a metallurgical furnace, comprising:

[0010] The high-temperature flue gas discharged from the kiln first enters the waste heat boiler, which is equipped with boiler pipes. The boiler pipes are connected to the upstream water pump to pump cooling water into the system to complete the circulation;

[0011] Under the convection and radiation heating of the high-temperature flue gas, the liquid water in the boiler tube boils to form superheated steam, which is introduced into the preheater through the pipeline to heat the low-temperature gas-phase feed;

[0012] The compressor is connected upstream of the low-temperature gas phase feed, and the spray gun is connected downstream to spray the preheated high-temperature gas phase directly into the furnace. At this time, the high-temperature steam is still in a supersaturated state and is used to drive the downstream generator to generate electricity;

[0013] After releasing heat energy, the high-temperature steam turns into liquid, and finally flows back into the water tank and is pumped into the waste heat boiler again by the water pump, forming a complete cycle.

[0014] As a further improvement of the present invention, the process of optimizing the arrangement of boiler tubes includes:

[0015] Collect basic parameters and operating conditions of the boiler, including fluid type, flow rate, temperature, heat load and material properties; use computer-aided software to design the geometric model of the boiler interior, including boiler tubes, flue gas channels and heat exchange areas;

[0016] Import the geometric model into the computational fluid dynamics software, perform meshing, and generate the finite element mesh required for calculation; determine the temperature, pressure, and velocity of the inlet fluid, and set the discharge conditions and boundary conditions of the wall temperature;

[0017] Run computational fluid dynamics software simulation and perform numerical calculations to obtain numerical solutions for fluid flow and heat exchange in the boiler, including velocity field, temperature field and pressure distribution; visualize the computational fluid dynamics software simulation results, and analyze the flow state and heat conduction effect of the fluid in the boiler through streamline diagrams, temperature cloud diagrams and pressure distribution diagrams; obtain different pipeline layout methods based on the analysis results, perform parameter sensitivity analysis, and evaluate the impact of each new layout on heat exchange efficiency and pressure loss; continue to perform multiple rounds of computational fluid dynamics software simulation and result analysis, and gradually optimize the boiler pipeline layout until the designed heat exchange efficiency and flow characteristics requirements are met.

[0018] As a further improvement of the present invention, the process of meshing includes:

[0019] Perform preliminary global meshing on the entire geometric model, set a coarse mesh, and perform local meshing at the boiler tube inlet / outlet, heat exchange area, and corners / joints;

[0020] Check mesh quality indicators using CFD software tools such as unit angle distribution, unit ratio and mesh size variation;

[0021] Export the mesh to a format recognized by the CFD software; generate the corresponding input file based on the mesh division.

[0022] As a further improvement of the present invention, the following steps are also included:

[0023] A temperature monitoring module is set between the compressor and the spray gun after the compressor enters the air preheater for heating, so as to control the compressor pressure;

[0024] The spray volume and spray angle of the spray gun are adjusted in real time through intelligent control algorithms to adapt to changes in temperature and pressure in the furnace;

[0025] Use organic Rankine cycle integrated with waste heat power generation units to recover energy from high-temperature flue gas and superheated steam; establish scheduling and control strategies to coordinate the operation of waste heat power generation units under different loads and operating conditions.

[0026] As a further improvement of the present invention, the process of regulating the compressor pressure includes:

[0027] A temperature monitoring module is provided to monitor the temperature of the heated hot air, establish a connection with the compressor, and preset a threshold value for the temperature sensor;

[0028] The temperature monitoring module collects the hot air temperature data in the boiler tube and compares it with the preset threshold. Through comparison, if the collected temperature reaches or exceeds the set temperature threshold, the compressor pressure is kept unchanged; if the collected temperature is lower than the preset temperature threshold, the compressor reduces the pressure;

[0029] The results are monitored according to the temperature in the metallurgical furnace, and the compressor pressure and the set temperature threshold are regulated.

[0030] As a further improvement of the present invention, the process of the intelligent control algorithm adjusting the spray volume and spray angle of the spray gun in real time includes:

[0031] Establish a temperature and pressure sensor network to continuously monitor the temperature and pressure in the furnace and transmit real-time data to the control system; collect flow and fuel type sensor data at the same time; filter and process the data collected from the sensors to analyze the current operating status in the furnace, detect real-time changes in temperature and pressure, and compare them with the set target values;

[0032] Using neural network intelligent control algorithm, the required spray volume and injection angle are determined according to real-time data; according to the changes in temperature and pressure in the furnace, the spray volume is automatically increased or decreased if the temperature is too high or too low; the change in injection angle will be adjusted according to the airflow characteristics of the flow field in the furnace to optimize the mixing of airflow and fuel;

[0033] The calculated control instructions for spray volume and injection angle are sent to the spray gun control system; the spray gun adjusts the spray output and injection angle in real time according to the received instructions; after the nozzle is adjusted, the temperature and pressure changes in the furnace continue to be monitored in real time; the effects of changes in spray volume and injection angle are evaluated, and the combustion efficiency and emissions are analyzed to see if they meet the set requirements; if the situation still does not meet the preset target, the intelligent control algorithm will be adjusted again according to the current data to form a closed-loop control to ensure continuous optimization.

[0034] As a further improvement of the present invention, the process of establishing the scheduling and control strategy includes:

[0035] Install sensors on the waste heat generators to monitor key parameters such as temperature, pressure, flow, load and efficiency; upload real-time data to ensure that the dispatch strategy can be adjusted accordingly based on the latest operating conditions;

[0036] Use historical data and category analysis methods, combined with the operating environment, to predict future load demand and the upcoming peak load period based on the production plan; implement mathematical optimization algorithms to formulate scheduling strategies and optimally adjust the operating mode of the waste heat generator set;

[0037] Recover energy from high-temperature flue gas and superheated steam, and control the flow and temperature of the recovered fluid by adjusting pumps and valves; adopt the most suitable working mode under different working conditions to ensure the efficient operation of ORC; monitor the power generation efficiency and heat recovery efficiency of ORC, evaluate the deviation from the preset standard, and adjust the fluid flow or equipment operating parameters based on the current load to optimize the overall system performance.

[0038] As a further improvement of the present invention, the preheater pipelines inside the air preheater connected to the compressor are arranged, wherein the preheater pipelines are arranged in a 30° staggered arrangement;

[0039] The process of obtaining the parameters of the high-temperature pipeline inside the air preheater connected to the air compressor specifically includes the following steps: different metallurgical furnaces have different preheating injection flow m and target temperature T o The requirements are different. After setting the target flow rate and temperature, the core parameters of the preheater need to be calculated to achieve the expected heat exchange effect. These core parameters include the number of pipes n, the outer diameter of the pipe d o , pipeline length L and pipeline spacing △;

[0040] The target heat transfer capacity is determined according to the inlet and outlet temperatures and flow rates as follows:

[0041] Q aim =Cp·m·(T o -T i );

[0042] Where Cp is the specific heat capacity, m is the target preheating mass flow rate, T o is the target temperature, T i is the intake air temperature;

[0043] Actual heat exchange capacity:

[0044] Q real = kAΔt;

[0045] Where k is the heat transfer coefficient, A is the heat transfer area, and Δt is the average temperature difference between the two fluids;

[0046] Among them, for the shell and tube structure, the value range of K is 5 to 35, and the middle value of 20 is taken as the initial design value, which is accurately evaluated through CFD calculation; the total heat exchange area A is:

[0047] A=nπd o L;

[0048] Where n is the number of heat pipes, d o is the outer diameter of the heat pipe, L is the length of the heat pipe; in the design process, the size parameters are initially determined based on the furnace size and heat exchange capacity. The heat pipe length is 2 to 3m, and the diameter range is 32-100mm. Based on this, the total number of heat pipes n is obtained; the spacing is 3 to 5 times d o , the overall size of the heat exchanger is obtained; the average temperature difference Δt is calculated by the following formula:

[0049]

[0050] in is the average temperature of the inlet and outlet steam, is the average temperature of the inlet and outlet air;

[0051] The process of evaluating the global heat transfer effect of the air preheater includes:

[0052] Construct a three-dimensional geometric model of the preheater according to the actual size, and distinguish between the fluid area and the solid area. The solid domain and the fluid domain are collectively referred to as the computational domain; discretize the computational domain into three-dimensional grids, and determine the grid quality through parameters such as aspect ratio and twist angle; determine the physical model and control equations to be solved, including the continuity equation, momentum equation, energy equation and turbulence equation;

[0053] Given the mass flow rate and inlet temperature of high-temperature steam, the initial temperature and mass flow rate of low-temperature gaseous feed, the outlet static pressure of the high-temperature steam pipe, the static pressure of the gaseous feed outlet, and the interface between the fluid region and the solid region, the convection heat transfer coefficient is automatically calculated based on the flow rate and other characteristics;

[0054] Given the density of water vapor and low-temperature gas phase inlet, the ideal gas state equation is used to solve it, and the viscosity, thermal conductivity and specific heat capacity use the linear interpolation function of temperature; the pressure and velocity coupling method uses the SIMPLE algorithm, the convection term uses the second-order format discretization, and the pressure term uses the high-order format discretization;

[0055] Given boundary conditions, physical properties and solution format, given initial field, start calculation, and monitor calculation until convergence; extract the temperature of gas phase feed outlet to evaluate whether the expected target temperature is reached; extract the gas phase feed inlet and outlet pressure drop to evaluate the upstream compressor pressure ratio and power; extract the steam outlet temperature to evaluate the downstream power generation capacity.

[0056] To achieve the above object, the present invention provides the following technical solutions:

[0057] A high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace, which is applied to the high-temperature flue gas heat energy recovery and utilization method for a metallurgical furnace, and the high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace comprises: a compressor, an air preheater, a waste heat boiler, a pump, a generator, a spray gun, a metallurgical furnace, and high-temperature flue gas;

[0058] Among them, the compressor is connected to the air preheater through a pipeline, the air preheater is connected to the waste heat boiler through a pipeline, the pump is connected to the air preheater and the waste heat boiler through a pipeline, the generator is connected to the air preheater, and the spray gun is connected to the compressor and the metallurgical furnace.

[0059] As a further improvement of the present invention, the air preheater comprises a low-temperature gas phase feed inlet, a guide plate, a high-temperature heat pipe, a preheater outer wall, a high-temperature gas phase feed outlet, a sealing partition, a superheated steam outlet, a heat compensator, and a superheated steam inlet;

[0060] Among them, a superheated steam inlet is arranged at the bottom of the air preheater, and each superheated steam inlet enters the interior of the air preheater through the boiler tube and the heat compensator. A low-temperature gas-phase feed inlet is opened at the bottom of the air preheater and close to the top of the heat compensator. The superheated steam outlet at the bottom of the air preheater is separated from the interior by a sealing partition, and guide plates are staggered inside. A high-temperature heat penetrating the interior of the air preheater is installed near the outer wall of the preheater, and a high-temperature gas-phase feed outlet is arranged at the same side as the low-temperature gas-phase feed inlet, close to the bottom of the sealing partition.

[0061] The present invention can improve the initial temperature of the furnace intake air and reduce the consumption of fuels such as coal / natural gas through the method for recovering the heat energy of high-temperature flue gas from metallurgical furnaces; at the same time, the high-temperature gas is beneficial to improving the combustion efficiency, accelerating the melting speed of materials, and improving the smelting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A schematic flow chart of the steps of an embodiment of a method for recovering heat energy of high-temperature flue gas from a metallurgical furnace of the present invention;

[0063] Figure 2 A schematic flow chart of the steps of optimizing the arrangement of boiler tubes in one embodiment of a method for recovering heat energy from high-temperature flue gas in a metallurgical furnace according to the present invention;

[0064] Figure 3 A schematic flow chart of the steps of compressor control in one embodiment of the method for recovering heat energy of high-temperature flue gas from a metallurgical furnace of the present invention;

[0065] Figure 4 A schematic diagram of a preheater pipeline arrangement diagram of an embodiment of a method for recovering heat energy of high-temperature flue gas from a metallurgical furnace of the present invention;

[0066] Figure 5 A schematic flow chart of the steps of evaluating the global heat exchange effect of an air preheater in one embodiment of a method for recovering and utilizing heat energy of high-temperature flue gas in a metallurgical furnace of the present invention;

[0067] Figure 6 It is a structural schematic diagram of an embodiment of a high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace of the present invention;

[0068] Figure 7 It is a structural schematic diagram of an air preheater of one embodiment of a high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace of the present invention;

[0069] Figure 8 It is a schematic structural diagram of a heat compensator of an embodiment of a high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace of the present invention;

[0070] Fig. 9 It is a side view of a thermal compensator of an embodiment of a high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace of the present invention;

[0071] Fig.10 It is a structural schematic diagram of an embodiment of an electronic device of the present invention;

[0072] Fig.11 It is a schematic structural diagram of an embodiment of the storage medium of the present invention. DETAILED DESCRIPTION

[0073] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0074] The terms "first", "second" and "third" in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as "first", "second" and "third" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0075] Reference to an "embodiment" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0076] like Figure 1 As shown, this embodiment provides an embodiment of a method for recovering heat energy from high-temperature flue gas of a metallurgical furnace. In this embodiment, the superheated steam generated by the waste heat boiler is first used to preheat the gas phase feed and then to generate electricity. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace specifically includes the following steps:

[0077] Step S1: The high-temperature flue gas discharged from the kiln first enters the waste heat boiler, in which a boiler pipe is arranged. The boiler pipe is connected to an upstream water pump to pump cooling water into the system to complete the circulation;

[0078] Step S2: Under the convection and radiation heating of the high-temperature flue gas, the liquid water in the boiler tube boils to form superheated steam, and the superheated steam is introduced into the preheater through the pipeline to heat the low-temperature gas-phase feed;

[0079] Step S3: The compressor is connected to the upstream of the low-temperature gas phase feed, and the spray gun is connected to the downstream, so that the preheated high-temperature gas phase is directly sprayed into the furnace. At this time, the high-temperature steam is still in a supersaturated state and is used to drive the downstream generator to generate electricity;

[0080] Step S4: The high-temperature steam releases heat energy and turns into liquid, and finally flows back into the water tank and is pumped into the waste heat boiler again by the water pump, forming a complete cycle.

[0081] Preferably, in the heat exchange process of the waste heat boiler in step S1 of this embodiment, the high-temperature flue gas enters the waste heat boiler for heat exchange, thereby extracting the heat energy in the flue gas; the boiler tube forms a closed loop by pumping cooling water into the system to achieve effective heat transfer. Improved energy efficiency: recover the heat energy discharged from the furnace, reduce environmental thermal pollution, and improve overall energy efficiency; maximize resource utilization: maximize the use of the heat energy of high-temperature flue gas through the waste heat boiler to reduce energy consumption. Step S2 steam generation and preheating application, under the heating effect of the high-temperature flue gas in the boiler, the liquid water in the boiler tube is heated to boiling and converted into superheated steam; the high-temperature steam is introduced into the preheater to heat the low-temperature gas-phase feed and increase its temperature. Improved efficiency: superheated steam uses the waste heat of flue gas for efficient heating, reducing the heat energy demand of subsequent processes; energy saving and consumption reduction: effectively utilize the generated heat, significantly reduce the heating energy consumption of the low-temperature gas-phase feed, thereby saving energy and reducing operating costs. Step S3: Injection and power generation of high-temperature gas phase. The preheated high-temperature gas phase is directly injected into the kiln through the compressor spray gun, and the high-temperature gas is used to participate in the smelting process; the high-temperature steam drives the downstream generator to generate electricity in an oversaturated state, converting heat energy into electrical energy. Increase output value: Use waste heat directly for smelting or power generation, so that heat energy can be converted into material and electrical energy, improving overall economic benefits; Reduce external energy dependence: Through power generation facilities, autonomously generate electricity during the production process, reduce dependence on external power supply, and achieve energy self-sufficiency. Step S4: Reflux and system circulation of liquid water. After releasing heat energy, high-temperature steam is converted into liquid water and enters the water tank through reflux; liquid water is pumped back to the waste heat boiler through a water pump to form a closed-loop circulation system. Achieve a complete cycle: Keep the heat recovery system in a continuous operation state and enhance overall energy efficiency; Environmentally friendly and sustainable development: Reduce exhaust gas emissions and environmental thermal pollution, and play a sustainable development effect; Improve economic benefits: Reduce the expenditure required for raw materials and energy through maximum resource recovery and utilization.

[0082] In summary, through the above steps, the heat recovery and utilization system of the metallurgical furnace in this embodiment can effectively recover and utilize the waste heat in the high-temperature flue gas, which not only improves the energy efficiency and economic benefits of production, but also helps to achieve environmental protection goals and promote sustainable development. Therefore, this technology has important application value in the modern metallurgical industry. Step S1 arranges the equipment so that the cooling water can be heated to boiling after the high-temperature flue gas enters the waste heat boiler; Step S2 heats the cooling water pumped in Step S1 to boiling to form superheated steam, which is used to heat the low-temperature gas phase feed; In Step S3, the superheated steam heats the low-temperature gas phase and sprays the heated high-temperature gas phase into the metallurgical furnace, and the remaining supersaturated steam is used for downstream power generation; In Step S4, the high-temperature steam releases heat energy to generate electricity and then turns into liquid, and finally flows into the water tank to enter the next cycle.

[0083] This embodiment uses the high-temperature flue gas heat energy recovery and utilization method of the metallurgical furnace to increase the initial temperature of the furnace intake air and reduce the consumption of fuels such as coal / natural gas; at the same time, the high-temperature gas is beneficial to improving combustion efficiency, accelerating the melting speed of materials, and improving smelting efficiency.

[0084] Furthermore, if Figure 2 As shown, the boiler tube layout optimization process in step S2 specifically includes the following steps:

[0085] Step S21: Collect basic parameters and operating conditions of the boiler, including fluid type, flow rate, temperature, heat load and material properties; use computer-aided software to design the geometric model of the boiler interior, including boiler tubes, flue gas channels and heat exchange areas;

[0086] Step S22: importing the geometric model into computational fluid dynamics software, performing mesh division, and generating the finite element mesh required for calculation; determining the temperature, pressure and velocity of the inlet fluid, and setting the discharge condition and the boundary condition of the wall temperature;

[0087] Step S23: Run the computational fluid dynamics software simulation, perform numerical calculations, and obtain numerical solutions for fluid flow and heat exchange in the boiler, including velocity field, temperature field, and pressure distribution; visualize the computational fluid dynamics software simulation results, and analyze the flow state and heat conduction effect of the fluid in the boiler through streamline diagrams, temperature cloud diagrams, and pressure distribution diagrams; obtain different pipeline layout methods based on the analysis results, perform parameter sensitivity analysis, and evaluate the impact of each new layout on heat exchange efficiency and pressure loss; continue to perform multiple rounds of computational fluid dynamics software simulations and result analysis, and gradually optimize the boiler pipeline layout until the designed heat exchange efficiency and flow characteristics requirements are met.

[0088] Preferably, in step S21 of this embodiment, basic data collection and geometric model design ensure that the basic data for subsequent analysis and simulation are true and valid by accurately collecting data such as fluid type, flow rate, temperature, heat load and material properties; use computer-aided design (CAD) software to create a detailed geometric model of the boiler interior, including boiler tubes, flue gas channels and heat exchange areas. This model provides a visual and structured basis for CFD simulation. Provide a reliable data foundation: accurate basic data and geometric models are the prerequisites for effective CFD analysis, ensuring the credibility of subsequent calculation results; improve design ideas: in the design stage, the internal structure of the boiler can be visualized, which helps designers better understand the fluid flow and heat exchange process and optimize the design scheme. Step S22 meshing and boundary condition setting, by dividing the geometric model into several finite element meshes, so as to perform numerical calculations in CFD simulation, reasonable meshing is critical to capturing the details of fluid flow; clarify the temperature, pressure, velocity of the inlet fluid, as well as the boundary conditions such as discharge conditions and wall temperature, to provide accurate physical constraints for CFD simulation. Accuracy of numerical calculation: Appropriate grid division and rigorous boundary condition setting directly affect the accuracy of CFD simulation, which can effectively improve the reliability of simulation results; Ensure the physical authenticity of simulation: The setting of boundary conditions ensures that CFD simulation can reflect the actual operation situation and provide a reference basis for practical application. Through simulation calculation and result analysis, run CFD software for numerical calculation, obtain important data such as velocity field, temperature field and pressure distribution, and display the flow state through visualization tools, which is easy to analyze and understand; Flow optimization and optimization iteration: Through the result analysis after visualization, identify the flow poor area and thermal uneven area, and perform parameter sensitivity analysis to evaluate the impact of different pipeline layouts on heat exchange efficiency and pressure loss, so as to perform design iteration optimization. Improve heat exchange efficiency: Through continuous iteration and optimization, the optimal pipeline layout solution can be found in the end, which can significantly improve the heat exchange efficiency of the boiler, reduce energy consumption and operating costs; Accurately identify problem areas: Visualization results help designers quickly identify problem areas in the system (such as flow dead zones and temperature anomalies) and make targeted improvements to improve overall performance and safety.

[0089] In summary, the data collection and model design of this embodiment provide the basic conditions for subsequent work, the grid division and boundary conditions ensure the accuracy and authenticity of the numerical calculation, and the simulation calculation and analysis are the core of the optimization solution, which is directly related to the improvement of the final boiler performance. It can significantly improve the design efficiency and operation efficiency of the boiler and achieve higher energy utilization. It is not only applied to boiler design, but also can be extended to the optimization of other types of heat exchange equipment and fluid systems.

[0090] Furthermore, the process of meshing in step S22 specifically includes the following steps:

[0091] Step S221: Perform preliminary global meshing on the entire geometric model, set a coarse mesh, and perform local meshing at the boiler tube inlet / outlet, heat exchange area, and corners / joints;

[0092] Step S222: Check the mesh quality index using the tool unit angle distribution, unit ratio and mesh size change of the CFD software;

[0093] Step S223: Export the mesh into a format recognized by the CFD software; generate a corresponding input file based on the mesh division.

[0094] Preferably, the step S221 of this embodiment performs preliminary global meshing and local encryption, and performs coarse meshing on the entire geometric model, which can quickly provide a basic mesh structure for flow field simulation, and provide a preliminary calculation basis while maintaining the overall characteristics of the model; local encryption is performed for key areas such as boiler tube inlet / outlet, heat exchange area, and corners / joints, so that the meshes in these specific areas are denser, so that flow changes and heat exchange conditions can be captured in detail. Improve computational efficiency: coarse meshing provides flexibility for initial simulations, can quickly identify potential flow patterns and heat exchange trends, and saves computing resources and time; enhance detail capture capabilities: local encryption enables high-resolution analysis of flow field behavior and heat conduction in areas with complex flows, ensuring the accuracy of calculations of important parameters (such as temperature and pressure); effectively identify problem areas: preliminary meshing enables designers to quickly identify key areas of the model, providing a basic basis for subsequent optimization. Step S222: Check the grid quality index. Use the tools provided by the CFD software to detect the grid quality, including the evaluation of indicators such as unit angle distribution, unit ratio, and grid size change to ensure that the grid structure is reasonable; Reduce numerical errors: By checking and optimizing the grid quality, reduce the numerical errors caused by poor unit deformation, and ensure the stability and accuracy of the calculation results; Ensure the reliability of numerical calculations: High-quality grids directly affect the accuracy of CFD calculations, and poor grids may lead to erroneous flow field simulation results or numerical non-convergence problems; Improve the stability of simulations: Good grid quality can enhance the overall stability of CFD simulations, ensure the physical significance of simulation results, reduce numerical oscillations and adverse effects, and thus improve the credibility of engineering design; Provide guarantees for subsequent calculations: Good grid quality is the basis for the subsequent CFD calculations to run successfully and obtain effective results, avoiding complex corrections caused by grid problems in subsequent operations. Step S223: Grid export and input file generation: Export the optimized grid to a format that the CFD software can recognize, ensuring that the grid can be read and used smoothly in the subsequent calculation stage; According to the grid division, generate the corresponding input file, which contains information such as boundary conditions and fluid properties, and set the necessary parameters for CFD simulation. Achieve computational fluency: Ensure that the created mesh can be seamlessly applied in the CFD software by exporting in the correct format, avoiding computational errors or failures due to data format mismatch; Provide a basis for numerical calculations: The integrity and correctness of the input files ensure that the CFD software can correctly understand and execute the simulation, which is crucial for subsequent physical process analysis; Optimize workflow: Clear and standardized mesh export and input file generation steps improve the efficiency of the entire CFD workflow, allowing designers to simulate and analyze more efficiently.

[0095] In summary, in the entire meshing process of this embodiment, each step has its specific technical effect and important significance. Global meshing and local encryption lay the foundation for subsequent simulations, mesh quality inspection ensures calculation accuracy and reliability, and mesh export and input file generation provide the necessary conditions for the final CFD simulation. The organic combination of these steps can effectively improve the optimization efficiency of boiler pipeline layout, help achieve design goals, and improve energy efficiency and system performance.

[0096] Furthermore, if Figure 3 As shown, step S3 specifically further includes the following steps:

[0097] Step S31: a temperature monitoring module is provided between the compressor and the spray gun after the compressor enters the air preheater for heating, so as to adjust the compressor pressure;

[0098] Step S32: adjusting the spray volume and spray angle of the spray gun in real time through an intelligent control algorithm to adapt to changes in temperature and pressure in the furnace;

[0099] Step S33: Use the organic Rankine cycle to integrate with the waste heat power generation unit to recover energy from the high-temperature flue gas and superheated steam; establish a scheduling and control strategy to coordinate the operation of the waste heat power generation unit under different loads and operating conditions.

[0100] Preferably, in step S31 of this embodiment, a temperature monitoring module is set. After the compressor enters the air preheater for heating, the temperature monitoring module is installed between the spray gun and the compressor. The temperature changes in the furnace can be monitored in real time and key data can be provided for subsequent control. This monitoring module collects data and feeds back to the control system to provide a basis for adjusting the compressor pressure to maintain the stability and efficiency of the system. Improve the system response capability: Real-time temperature monitoring enables the operator or automatic control system to quickly respond to changes in furnace conditions and ensure that the pressure value of the compressor is timely and reasonable; Optimize fuel use: By scientifically regulating the pressure of the compressor, the combustion efficiency can be improved, fuel consumption can be reduced, thereby reducing operating costs and emissions; Improve safety: Monitoring temperature changes can timely discover potential safety hazards, prevent equipment from over-temperature operation, and enhance the safety of the boiler system. Step S32 Intelligent adjustment of the spray gun spray volume and injection angle, implement intelligent control algorithms, so that the spray gun can automatically adjust the spray volume and injection angle according to the real-time monitored furnace temperature and pressure conditions, and optimize the combustion process; The adjustment capability of the spray gun can adapt to dynamically changing working conditions, making the mixing of fuel and air more uniform, which is conducive to improving combustion efficiency and heat transfer efficiency. Improve combustion efficiency: Precise adjustment of spray volume and injection angle can maximize the uniformity and efficiency of combustion, and help reduce the loss of unburned fuel; Reduce pollutant emissions: More efficient combustion means more complete combustion of diesel, coal or other fuels, which helps reduce the emission of harmful gases such as CO and NOx; Promote economic operation: The implementation of intelligent control can achieve continuous optimization under different working conditions, which helps to improve the economic operation level and stability of the system. Step S33 integrates the organic Rankine cycle with the waste heat generator set. The integration of the organic Rankine cycle with the waste heat generator set can effectively recover the heat energy lost in high-temperature flue gas and superheated steam and convert it into electrical energy; Improve the utilization rate of thermal effect: Improve the overall system energy efficiency: Through the recovery of waste heat energy, the utilization rate of energy can be significantly improved, and a higher heat energy conversion efficiency can be achieved; Reduce operating costs: Effective energy recovery reduces dependence on external energy, reduces the cost of fuel used, and improves economic benefits; Reduce environmental impact: Reducing exhaust gas and waste heat emissions not only helps to improve environmental quality, but also supports the goal of sustainable development, and meets the requirements of modern energy utilization and environmental protection.

[0101] In summary, each step of this embodiment has its unique and critical technical effect and practical significance in the design and operation of the system. Through effective temperature monitoring and feedback mechanism, flexible adjustment of intelligent algorithms and combination of energy recovery technology, the efficiency of the boiler system can be significantly improved, and the operating cost and environmental impact can be reduced. These measures together constitute a complete system for boiler pipeline optimization, providing an important guarantee for achieving efficient, safe and economical operation.

[0102] Furthermore, the process of regulating the compressor pressure in step S31 specifically includes the following steps:

[0103] Step S311: setting a temperature monitoring module to monitor the temperature of the heated hot air, establishing a connection with the compressor, and presetting a threshold value for the temperature sensor;

[0104] Step S312: The temperature monitoring module collects the hot air temperature data in the boiler tube and compares it with the preset threshold value. Through the comparison, if the collected temperature reaches or exceeds the set temperature threshold value, the compressor pressure is kept unchanged; if the collected temperature is lower than the preset temperature threshold value, the compressor reduces the pressure;

[0105] Step S313: Monitor the results according to the temperature in the metallurgical furnace, and adjust the compressor pressure and the set temperature threshold.

[0106] Preferably, this embodiment sets a threshold to control the compressor pressure, which is used to control the flow rate of air in the boiler tube, so as to control the temperature of the hot air entering the metallurgical furnace, reduce the content of normal temperature gas entering the metallurgical furnace, reduce the use of fuel, and reduce production costs. Step S311 sets a temperature monitoring module, configures a dedicated temperature monitoring module, and connects the heated hot air and the compressor; presets a threshold for the temperature sensor so that the module can effectively identify temperature changes and send corresponding control signals; real-time monitoring capability: the temperature monitoring module provides real-time seamless temperature acquisition capabilities, which can timely feedback the status of the hot air and ensure the responsiveness of the system; preventive safety measures: by setting the temperature threshold, it can identify potential overheating or low temperature conditions early, provide necessary warnings and controls, and enhance boiler safety; optimize the basis for control: provide data basis for subsequent compressor pressure control, so that the system can automatically adjust according to the collected data, and improve the intelligent level of control. Step S312 monitors the temperature data and compares it with the threshold value. The temperature monitoring module regularly collects the hot air temperature data in the boiler tube and compares it with the preset threshold value in real time. According to the comparison result, if the temperature reaches or exceeds the threshold value, the compressor pressure is kept unchanged; if it is lower than the threshold value, the compressor pressure is automatically reduced. Stable control effect: By dynamically adjusting the compressor pressure according to the real-time temperature, the system can maintain a stable operating state, optimize resource allocation, and avoid invalid or excessive operation. Energy saving and consumption reduction: The control mechanism that automatically reduces the compressor pressure can reduce unnecessary energy consumption and optimize fuel use, thereby achieving energy saving effects and reducing operating costs. Enhanced adaptability: This process enhances the system's ability to adapt to changes in operating conditions, allowing it to flexibly respond to the impact of temperature fluctuations, which helps to improve overall efficiency. Step S313 Temperature monitoring and pressure control: Based on the temperature results in the metallurgical furnace, the thermal state of the entire system is continuously monitored, and the relationship between pressure and temperature is analyzed. Intelligent control mechanism: According to real-time monitoring data, the compressor pressure setting and preset threshold are adjusted in time to ensure that the system operates under optimal working conditions. Comprehensive system optimization: The integrated temperature and pressure monitoring mechanism realizes the comprehensive optimization of the entire boiler system, ensuring the coordination of all parts and improving efficiency; improving the utilization rate of thermal energy: by reasonably regulating the compressor pressure, the effective utilization of thermal energy is guaranteed, thereby improving the overall thermal efficiency and achieving energy saving and environmental protection goals; enhancing response speed and flexibility: The rapid feedback capability of monitoring and regulation enables the system to have a strong adaptability, and can respond to abnormal situations in the operation of the furnace in a timely manner to ensure safe and stable operation.

[0107] In summary, the process of regulating the compressor pressure in this embodiment effectively integrates temperature monitoring, pressure control and system tuning through the above steps. Each step plays an important role in improving system stability, energy efficiency and safety. A closed-loop control system with real-time monitoring and dynamic adjustment is realized, which provides strong support for improving the overall operating performance of the boiler, reducing energy consumption and ensuring operational safety. Such a control mechanism is particularly important in modern industrial applications and provides a technical basis for promoting sustainable development.

[0108] Furthermore, the process of the intelligent control algorithm adjusting the spray volume and spray angle of the spray gun in real time in step S32 specifically includes the following steps:

[0109] Step S321: Establish a temperature and pressure sensor network to continuously monitor the temperature and pressure in the furnace and transmit real-time data to the control system; at the same time, collect other sensor data such as flow rate and fuel type; filter and process the data collected from the sensors, analyze the current operation status in the furnace, detect the real-time changes of temperature and pressure, and compare them with the set target values ​​(such as optimal combustion temperature, pressure range, etc.);

[0110] Step S322: Using a neural network intelligent control algorithm, the required spray volume and spray angle are determined based on real-time data; based on changes in temperature and pressure in the furnace, if the temperature is too high or too low, the spray volume will be automatically increased or decreased within a certain range; the change in the spray angle will be adjusted according to the airflow characteristics of the flow field in the furnace to optimize the mixing of airflow and fuel;

[0111] Step S323: Send the calculated control instructions for the spray volume and injection angle to the spray gun control system; the spray gun adjusts the spray output and injection angle in real time according to the received instructions; after the nozzle is adjusted, continue to monitor the temperature and pressure changes in the furnace in real time; evaluate the effect of the change in spray volume and injection angle, and analyze whether the combustion efficiency and emissions meet the set requirements; if the situation still does not meet the preset goals, the intelligent control algorithm will be adjusted again according to the current data to form a closed-loop control to ensure continuous optimization.

[0112] Among them, the assumed conditions and preset target values ​​are: target temperature: 800°C; target pressure: 150kPa;

[0113] Real-time monitoring data (sensor collection): Current furnace temperature: 780°C; Current furnace pressure: 140kPa;

[0114] Fuel type: natural gas; flow rate: 100kg / h;

[0115] Data collection: The following data were continuously monitored and obtained through the sensor network: Temperature: 780°C (lower than the target value of 800°C); Pressure: 140kPa (lower than the target value of 150kPa); Flowrate: 100kg / h; Fueltype: natural gas;

[0116] Data processing: After filtering and processing, the current state is analyzed; compared with the set target values, it is found that both temperature and pressure are lower than the target values;

[0117] Neural network analysis: Use a neural network model to predict the required spray volume (Q) and spray angle (A) based on current state data (temperature, pressure, flow, etc.).

[0118] Assume that the output of the neural network model is as follows: Predicted spray volume (Q) = 120 kg / h

[0119] Predicted spray angle (A) = 30° (from the horizontal line downward)

[0120] Adjusted based on current data:

[0121] Since the current temperature is lower than the target value, the control system decides to increase the spray volume by 30%.

[0122] New spray volume = (Q + 0.3\timesQ = 120, kg / h + 0.3\times120, kg / h = 156, kg / h)

[0123] Optimize spray angle:

[0124] According to the flow field characteristics, if the current flow direction is to the right, the spray angle is adjusted to 25° (to allow the spray particles to mix better with the airflow);

[0125] Control command sending: send the adjusted spray volume 156kg / h and spray angle 25° to the spray gun control system; the spray gun is adjusted in real time according to the received command: set the spray output to 156kg / h and adjust the spray angle to 25°; continuous monitoring and evaluation:

[0126] After the nozzle is adjusted, continue to monitor the temperature and pressure changes in the furnace. Assume that after adjustment, the monitoring data becomes: current furnace temperature: 810℃ (suitable for the target range); current furnace pressure: 155kPa (close to the target range); analyze the combustion efficiency and whether the emission situation meets the set requirements; the actual emission calculation shows that the emission substances are within the qualified range; if the result is qualified, the system will save the current spray volume and injection angle; closed-loop feedback: if the situation still does not reach the preset target, the intelligent control algorithm will continue to adjust according to the new real-time data. Assuming that the temperature returns to 798℃ and the pressure returns to 148kPa, the control system will make corresponding adjustments again.

[0127] Preferably, the data acquisition and analysis in step S321 of this embodiment can obtain the operating status data in the furnace in real time by establishing a temperature and pressure sensor network; integrate the data of multiple sensors (such as flow rate, fuel type, etc.) to provide a comprehensive information basis for subsequent analysis; the filtered and processed data can accurately identify the current operating status in the furnace to ensure the accuracy and reliability of the information. Dynamic adaptation: real-time monitoring allows the system to quickly identify and respond to changes in the furnace and optimize control decisions; improve safety: by monitoring the temperature and pressure in the furnace, abnormal conditions can be discovered early to avoid safety accidents; basic data provision: provide important decision-making basis for subsequent control algorithms to ensure that the algorithm operates on accurate data. Step S322 intelligent control algorithm calculation, using a neural network intelligent control algorithm to predict the required spray volume and injection angle based on real-time data; the algorithm can automatically adjust the spray volume according to the changes in the temperature and pressure in the furnace to respond to actual needs; adjust the injection angle based on the airflow characteristics to ensure that the airflow and fuel are fully mixed to improve combustion efficiency. Improve combustion efficiency: By accurately controlling the spray volume and injection angle, the efficiency and stability of combustion can be significantly improved; Energy saving and emission reduction: The optimized combustion process can reduce exhaust emissions, reduce environmental pollution, and achieve sustainable development; Improve the level of intelligence: The introduction of intelligent algorithms makes the control system more flexible and adaptable, which is in line with the trend of modern industrial automation. Step S323 performs control and feedback evaluation, and the control instructions are quickly sent to the spray gun control system to achieve rapid adjustment of spray output and injection angle; after adjustment, continue to monitor the temperature and pressure in the furnace, conduct effect evaluation, and analyze whether the combustion efficiency and emissions meet the standards; if the situation does not meet the standards, adjust again through feedback information to form a closed-loop control system. Operational flexibility: The ability to quickly adjust strategies based on actual feedback to improve the system's ability to adapt to changes; Continuous monitoring of efficiency and quality: Ensure that the effect of each adjustment can be verified to ensure the stability of the production process and product quality; System self-optimization: Through the feedback mechanism, the system can continuously optimize itself, gradually improve the overall operating efficiency, and reduce operating costs.

[0128] In summary, through the analysis of the technical effects and significance of each step in this embodiment, it can be seen that the design of the intelligent control algorithm not only improves the operating efficiency and stability of the internal combustion engine, but also plays a positive role in improving safety, saving energy and reducing emissions. The closed-loop control formed by integrating sensor data, intelligent algorithms and real-time feedback conforms to the requirements of modern industry for intelligence, automation and environmental protection, and has great application value and development prospects.

[0129] Furthermore, the process of establishing the scheduling and control strategy in step S33 specifically includes the following steps:

[0130] Step S331: Install sensors on the waste heat generator set to monitor key parameters such as temperature, pressure, flow, load and efficiency; upload real-time data to ensure that the scheduling strategy can be adjusted accordingly based on the latest operating conditions;

[0131] Step S332: Utilize historical data and category analysis methods, combined with the operating environment, to predict future load demand, and predict the upcoming peak load period according to the production plan; implement mathematical optimization algorithms to formulate scheduling strategies, and optimally allocate the operating mode of the waste heat generator set to maximize energy recovery and power generation efficiency;

[0132] The scheduling strategy sets how to operate the waste heat generator set under different time periods, load conditions and working conditions. The specific contents include:

[0133] Load Forecasting:

[0134] Data sources: Use historical operation data, production plans, seasonal changes, external environmental factors (such as temperature, market demand, etc.) and other data;

[0135] Predictive models: Apply time series analysis, machine learning algorithms, or linear regression models to predict upcoming load demand, with a focus on forecasting and analyzing peak load periods;

[0136] Resource Allocation:

[0137] Priority setting: define the operation priority of different devices under various load conditions to ensure that key devices (such as hosts) have priority in obtaining resources when the load is high;

[0138] Operation mode switching: According to the load changes, determine when to switch to different operation modes (such as switching from grid-connected operation to independent operation);

[0139] Optimize the scheduling plan:

[0140] Scheduling algorithm: Choose to use linear programming, dynamic programming or heuristic optimization methods (such as genetic algorithm, particle swarm optimization) to formulate the operation schedule and optimal scheduling order of the waste heat power generation unit;

[0141] Maximize power generation efficiency: Optimize the start, stop and operating load of the generator set according to the current and predicted load conditions to maximize energy recovery and power generation efficiency.

[0142] Coordinated operation:

[0143] Integrate the scheduling requirements of the main system: ensure that the scheduling strategy of the waste heat generator unit is designed in coordination with the main system (such as furnace, compressor, etc.) to avoid operation conflicts;

[0144] Real-time feedback mechanism: A feedback mechanism is set up during operation to monitor the deviation between actual load and predicted load so as to adjust the scheduling strategy in real time;

[0145] Step S333: Establish real-time control and dynamically adjust the waste heat generator set based on real-time data (temperature, pressure, load, etc.); coordinate the load and operating conditions of the waste heat generator set and the main system through control strategies; for example, when high-temperature flue gas is available, increase the operating ratio of ORC; when the load is low, appropriately reduce the operating power of the generator set to avoid efficiency reduction;

[0146] Among them, the control strategy is the execution level of the waste heat generator set, ensuring that the system maintains its performance and safety in real-time operation. The specific contents include:

[0147] Real-time monitoring and adjustment:

[0148] Data real-time: By installing sensors such as temperature, pressure, flow, and load, the operating status of the equipment is continuously monitored and the data is transmitted to the control center in real time;

[0149] Dynamic feedback control: Set a threshold value. Once the real-time monitoring data exceeds the preset safety standard or efficiency standard, the system will automatically adjust the operating status of the equipment.

[0150] Condition-adaptive control:

[0151] Operation mode selection: According to the current high-temperature flue gas, superheated steam and other fluid characteristics, it automatically switches to the optimal operating mode (such as constant temperature and constant pressure mode) to ensure efficient energy recovery;

[0152] Fluid flow control: adjust the working state of the pump and the opening and closing of the valve according to the feedback parameters such as temperature and pressure, and recover heat energy at the optimal flow and temperature;

[0153] Efficiency monitoring and optimization:

[0154] Efficiency evaluation: monitor the power generation efficiency and heat recovery efficiency of the generator set in real time, compare them with the preset targets, and analyze and adjust if there is a decrease in efficiency;

[0155] Parameter optimization: Through the control algorithm, the operating parameters of the ORC system (such as fluid flow, temperature, pressure, etc.) are adjusted to cope with load changes and improve the overall system performance;

[0156] Safety and Failure Protection:

[0157] Protection mechanism: Design emergency stop and safety protection strategies to take immediate measures to ensure equipment safety when the system detects an abnormality (such as over-temperature, over-pressure, etc.);

[0158] Fault detection and alarm: Establish a fault diagnosis system to monitor the equipment status in real time. Once a fault is found, issue an alarm in time and take corresponding preventive and repair measures;

[0159] Step S334: Recover energy from high-temperature flue gas and superheated steam, and control the flow and temperature of the recovered fluid by adjusting pumps and valves; adopt the most suitable working mode (such as constant temperature mode or constant pressure mode) under different working conditions to ensure the efficient operation of ORC; monitor the power generation efficiency and heat recovery efficiency of ORC, evaluate the deviation from the preset standard, and adjust the fluid flow or equipment operating parameters based on the current load to optimize the overall system performance.

[0160] Preferably, in step S331 of this embodiment, monitoring sensors are installed and real-time data is uploaded. By installing sensors of key parameters such as temperature, pressure, flow, load and efficiency, the operating status of the waste heat generator set and its related systems can be carefully monitored; the real-time data is uploaded to the central control system to realize centralized data processing and analysis. Decision-making basis: ensure that the scheduling strategy can be adjusted accordingly based on the latest operating conditions to improve the accuracy and real-time nature of decision-making; reduce risks: quickly identify abnormal situations (such as equipment failure, overheating, etc.), improve the safety of the system, and reduce potential risks. Step S332 load forecasting and scheduling strategy formulation, using historical data, production plans and external environmental factors, applying machine learning or mathematical statistics methods, accurately predict future load requirements; formulate scientific scheduling strategies, optimize the operating mode of the waste heat generator set, and ensure maximum energy recovery under different load conditions. Improve efficiency: by predicting peak load periods, reasonably allocate energy to maximize power generation efficiency; optimal resource utilization: effectively allocate resources to ensure that key equipment has priority access to resources during high loads, thereby improving the economic benefits of the overall system. Step S333 establishes real-time control and dynamic adjustment, performs dynamic adjustment according to real-time monitoring data, and responds to load changes and operating conditions in a timely manner; ensures that the waste heat generator set and the load and operating conditions of the main system (such as furnaces, compressors) operate in coordination to maximize energy utilization efficiency. Optimize operating conditions: increase the operating ratio of ORC when high-temperature flue gas is available, and reduce the power generation power when the load is low to ensure efficient and stable operation of the system; response flexibility: improve the system's response capability, adapt to changing operating conditions in real time, and reduce energy waste and performance loss. Step S334 Energy recovery and operating condition adaptability control, effective energy recovery: optimize the control of pumps and valves to ensure efficient recovery of heat energy from high-temperature flue gas and superheated steam; adjust the operating mode in a timely manner according to actual operating data to keep the system running efficiently in the best state. Continuously optimize performance: monitor and evaluate power generation efficiency and heat recovery efficiency to ensure that the system is always in the best operating state; improve system reliability: through dynamic optimization of operating parameters, enhance the adaptability and stability of the system and reduce the probability of failure. The entire scheduling and control strategy can significantly improve the power generation efficiency and economic returns of waste heat power generation units and reduce operating costs; Environmental benefits: effectively recover and utilize industrial waste heat, reduce energy consumption and emissions, and support the goal of sustainable development; Safety: Real-time monitoring and dynamic feedback mechanisms improve the safety of the system, and enhance the stability of the system through fault detection and protection measures; Flexibility and adaptability: The system can flexibly respond to load changes and operating condition fluctuations, improve overall scheduling flexibility, and ensure efficient operation in different scenarios.

[0161] In summary, this embodiment can better achieve efficient, economical and safe operation of the waste heat power generation unit and promote the sustainable utilization of energy.

[0162] Furthermore, the method for recovering heat energy from high-temperature flue gas of a metallurgical furnace provided in this embodiment further includes arranging the preheater pipes inside the air preheater connected to the compressor, wherein the preheater pipes are arranged in a 30° staggered arrangement (such as Figure 4 shown);

[0163] The process of obtaining the parameters of the high-temperature pipeline inside the air preheater connected to the air compressor specifically includes the following steps: different metallurgical furnaces have different preheating injection flow m and target temperature T o The requirements are different. After setting the target flow rate and temperature, the core parameters of the preheater need to be calculated to achieve the expected heat exchange effect. These core parameters include the number of pipes n, the outer diameter of the pipe d o , pipeline length L and pipeline spacing △;

[0164] The target heat transfer can be determined based on the inlet and outlet temperatures and flow rates as follows:

[0165] Q aim =Cp·m·(T o -Ti) (1)

[0166] Where Cp is the specific heat capacity, m is the target preheating mass flow rate, T o is the target temperature, T i is the intake air temperature;

[0167] Actual heat exchange capacity:

[0168] Q real =kAΔt (2)

[0169] Where k is the heat transfer coefficient, A is the heat transfer area, and Δt is the average temperature difference between the two fluids;

[0170] Among them, for the shell and tube structure, the value range of K is about 5 to 35. The middle value of 20 can be taken as the initial design value, and then accurately evaluated through subsequent CFD calculations; the total heat exchange area A is:

[0171] A=nπd o L (3)

[0172] Where n is the number of heat pipes, d o is the outer diameter of the heat pipe, and L is the length of the heat pipe. In the design process, the size parameters are initially determined based on the furnace size, heat exchange capacity, etc. For example, the heat pipe length is 2 to 3 meters, and the diameter range is 32-100 mm. Based on this, the total number of heat pipes n can be obtained; the spacing is 3 to 5 times d o , the overall size of the heat exchanger is obtained; the average temperature difference Δt can be calculated by the following formula:

[0173]

[0174] in is the average temperature of the inlet and outlet steam, is the average temperature of the inlet and outlet air.

[0175] Preferably, the advantages of this layout adopted in this embodiment are large heat transfer area and high density of heat exchange tubes; after setting the target flow and temperature, the expected heat exchange effect can be achieved by calculating the core parameters of the preheater; the disadvantages are large flow resistance outside the tube, large flow losses and large pressure drop, which can be solved by increasing the pressure ratio of the intake compressor; and refined design can be carried out through the computational fluid dynamics method in this embodiment.

[0176] This embodiment sets the preheater parameters and target heat exchange, sets the preheating injection flow rate and target temperature for the application of different metallurgical furnaces, and clarifies the design goals. The energy demand and preheating effect are concretized through the formula. Adaptive design: ensure that the design of the preheater can meet the process requirements of different furnaces and provide necessary technical support for actual operation; optimize resource utilization: through clear target heat exchange, rationally use energy, reduce unnecessary energy waste, and improve the economy of the overall system. The actual heat exchange calculation evaluates the actual heat exchange of the heat exchanger through the formula. The heat transfer coefficient (k) needs to be determined in the calculation; for shell and tube structures, select a reasonable heat transfer coefficient range (5 to 35) and take the middle value of 20 for preliminary design. Performance judgment: can clarify the difference between the actual performance of the heat exchanger and the design target, and provide a basis for subsequent performance improvement; design optimization efforts: through the calculation of the actual heat exchange, promote design optimization, so that the preheater is more efficient under real working conditions. Heat exchange area calculation uses the formula to calculate the total heat exchange area, which is realized by the number of pipes, the outer diameter of the pipes and the length of the pipes; according to the size of the furnace, the heat exchange amount and other factors that need to be considered in the design, the size parameters of the pipes are preliminarily determined. Structural effectiveness: The number and size of the pipes are reasonably designed to ensure that the preheater area can meet the requirements of the target heat exchange amount and improve the heat recovery effect; Overall design rationality: Ensure that the structure of the heat exchanger not only meets the heat exchange requirements, but also takes into account the rationality of fluid flow and the operability of the system. Average temperature difference calculation uses the formula to determine the average temperature difference, which is a key factor in heat exchange efficiency. By calculating the average temperature of the inlet and outlet steam and air, it provides a basis for the actual heat exchange evaluation. Key indicators for evaluating heat exchange effect: The average temperature difference directly affects the size of the heat exchange efficiency. On the one hand, it helps to judge whether the operation of the preheater can meet the standards, and on the other hand, it provides the necessary parameter basis for subsequent optimization and improvement; It is helpful for system adjustment: Through a deep understanding of the heat exchange capacity, the operating conditions, fluid parameters, flow rate, etc. can be further improved to improve the overall energy utilization efficiency.

[0177] In summary, through the technical effects and significance of the above steps in this embodiment, it can be concluded that the design and calculation process of the high-temperature flue gas heat energy recovery and utilization method can ensure that the preheater system operates at the highest efficiency and achieves the necessary heat exchange effect, thereby achieving the following goals to improve energy utilization efficiency: through precise design and calculation, improve the heat recovery ratio of high-temperature flue gas, save energy, and improve system efficiency; support sustainable development: efficient heat recovery not only reduces energy consumption, but also reduces emissions, supports the green development of industry and environmental protection; improves economic benefits: makes full use of industrial waste heat, reduces the energy cost of metallurgical production, and improves overall economic benefits; provides design basis: provides important technical parameters and design basis for subsequent practical applications and technical improvements, and promotes the reliable and stable operation of equipment. Through the detailed analysis of the above steps, the criticality and systematicness of the design and implementation process of high-temperature flue gas heat energy recovery are clarified, ensuring the combination of innovation and efficiency, and promoting the rational use of fuel and industrial energy efficiency improvement.

[0178] Furthermore, if Figure 5 As shown, the method for recovering heat energy from high-temperature flue gas of a metallurgical furnace provided in this embodiment also includes a process for evaluating the global heat exchange effect of an air preheater, which specifically includes the following steps:

[0179] Step S5: construct a three-dimensional geometric model of the preheater according to the actual size, and distinguish between the fluid area and the solid area (referring to the tube wall and the baffle, etc.), the solid domain and the fluid domain are collectively referred to as the calculation domain; discretize the calculation domain into a grid in three-dimensional space, and determine the grid quality through parameters such as aspect ratio and twist angle; determine the physical model and control equations to be solved, including the continuity equation, momentum equation, energy equation and turbulence equation;

[0180] Step S6: Given the mass flow rate and inlet temperature of the high-temperature steam, the initial temperature and mass flow rate of the low-temperature gaseous feed, the outlet static pressure of the high-temperature steam pipe, the static pressure of the gaseous feed outlet, and the interface between the fluid region and the solid region, a coupling plane is used to automatically calculate the convective heat transfer coefficient according to the flow rate and other characteristics;

[0181] Step S7: Given the density of water vapor and low-temperature gas phase inlet, the ideal gas state equation is used to solve, and the viscosity, thermal conductivity and specific heat capacity are solved using a linear interpolation function of the temperature; the pressure and velocity coupling method uses the SIMPLE algorithm, the convection term is discretized using a second-order format, and the pressure term is discretized using a high-order format;

[0182] Step S8: Given the initial field, start the calculation, and monitor the calculation until convergence; extract the temperature of the gas phase feed outlet to evaluate whether the expected target temperature is reached; extract the gas phase feed inlet and outlet pressure drops to evaluate the upstream compressor pressure ratio and power; extract the steam outlet temperature to evaluate the downstream power generation capacity.

[0183] Preferably, step S5 of this embodiment constructs a three-dimensional geometric model and mesh division, constructs a three-dimensional geometric model of the air preheater according to the actual size, and clearly distinguishes between fluid areas (such as gas, steam) and solid areas (such as pipe walls, baffles, etc.); discretizes the calculation domain into grids, and optimizes the grid quality using parameters such as aspect ratio and twist angle to improve the accuracy and convergence speed of numerical calculations. Accurate simulation: Through detailed geometric models and high-quality grids, the accuracy and reliability of simulation results are guaranteed, and numerical errors caused by poor grid quality are avoided; complex flow field reproduction: It can better reproduce the fluid flow and heat exchange process, capture key flow characteristics, and improve the effectiveness of the overall evaluation. Step S6 sets the fluid boundary conditions and heat transfer coefficient calculation, clarifies the boundary conditions such as mass flow rate, inlet temperature, and outlet static pressure of high-temperature steam and low-temperature gas phase fluids, and ensures the physical authenticity of the calculation; sets a coupling plane at the interface between the solid and fluid regions, and automatically calculates the convective heat transfer coefficient using features such as flow rate. Real feedback: Through the precise boundary condition setting, the calculation results are ensured to be highly consistent with the actual working conditions, which can reflect the actual operation conditions; heat transfer efficiency evaluation: It can effectively evaluate the heat transfer effect between the fluid and solid areas, and provide a basis for subsequent optimization. Step S7 Fluid physical property parameter solution and discretization processing, according to the temperature linear interpolation to obtain the density, viscosity, thermal conductivity and specific heat capacity of the fluid, improve the calculation accuracy; use SIMPLE algorithm for pressure and velocity coupling, second-order format discrete convection terms and high-order format discrete pressure terms to ensure the stability and convergence of numerical calculations. Improve calculation accuracy: By dynamically adjusting the physical property parameters to make them closer to the actual working conditions, the real reliability of the simulation is enhanced; optimize calculation efficiency: reasonable numerical solutions enable the calculation to converge quickly, saving computing resources and time. Step S8 Initial field setting and result monitoring and evaluation, set the initial field and start the calculation, monitor the iterative process until convergence to ensure the stability of the simulation; extract key parameters such as the temperature and pressure drop of the gas phase feed outlet, and the steam outlet temperature for effect evaluation. Performance evaluation: By extracting key data, we evaluate whether the preheater has reached the target temperature and whether the pressure drop meets the requirements, so as to determine whether its heat exchange effect meets the design requirements; Optimization suggestions: Through data analysis, we identify potential improvement points and provide valuable suggestions for subsequent design or system adjustment, which can further improve the thermal efficiency and economy of the overall system.

[0184] In this embodiment, the boundary conditions required before the initial field and calculation are given are as follows: mass flow rate and inlet temperature of high-temperature steam; initial temperature and mass flow rate of low-temperature gas-phase feed; outlet static pressure of high-temperature steam pipe; static pressure of gas-phase feed outlet; the interface between the fluid region and the solid region adopts a coupling plane, and the convective heat transfer coefficient is automatically calculated according to the flow rate and other characteristics;

[0185] The given physical properties are as follows: the density of water vapor is solved by the ideal gas state equation, and the viscosity, thermal conductivity and specific heat capacity are solved by the linear interpolation function of temperature; the density of low-temperature gas phase inlet gas is solved by the ideal gas state equation, and the viscosity, thermal conductivity and specific heat capacity are solved by the linear interpolation function of temperature;

[0186] Given the solution format: the pressure and velocity coupling method uses the SIMPLE algorithm; the convection term is discretized using the second-order format; the pressure term is discretized using the high-order format;

[0187] Processing calculation results: extract the temperature of the gas phase feed outlet to evaluate whether the expected target temperature has been reached; extract the gas phase feed inlet and outlet pressure drop to evaluate the upstream compressor pressure ratio and power; extract the steam outlet temperature to evaluate the downstream power generation capacity;

[0188] The feasibility of the current solution is evaluated based on the above three parameters, and the design is optimized by adjusting the number of heat pipes, the outer diameter of the heat pipes, L (the length of the heat pipes), the distance between the tube centers and other parameters until the expected goal is achieved.

[0189] In summary, this embodiment not only ensures the accurate evaluation of the heat exchange effect of the air preheater, but is also crucial to the optimization of the overall thermal system. The specific significance includes: providing an important basis for designing and improving the structure and operating conditions of the air preheater, effectively improving the thermal efficiency of the system; the results of automatic monitoring can be used for real-time performance monitoring to ensure the safe and reliable operation of the system; by optimizing the heat exchange effect, reducing energy consumption, improving overall economic benefits, and supporting sustainable development; providing quantitative data support for engineers and decision makers to guide subsequent actual operation and maintenance decisions. Through the effective implementation of these steps, the efficiency and reliability of the air preheater in industrial applications can be ensured, thereby promoting the overall performance improvement and optimization of the system. Repeat the above steps S5-S8, evaluate the feasibility of the current solution according to the above three parameters, and optimize the design by adjusting the number of heat pipes, the outer diameter of the heat pipes, L is the length of the heat pipes, the distance between the tube centers and other parameters, which can greatly increase the temperature of the injected gas and reduce the consumption of fuels such as coal and natural gas; at the same time, high-temperature gas is conducive to improving combustion efficiency, accelerating the melting rate of materials, and improving smelting efficiency.

[0190] Furthermore, in step S5, the design based on the empirical formula is relatively rough. This embodiment uses computational fluid dynamics to perform refined iterative design, including continuity equation, momentum equation, energy equation and turbulence equation;

[0191] Continuity equation:

[0192]

[0193] in is the velocity vector;

[0194] Momentum conservation equation:

[0195]

[0196] Where t is time, ρ is density, is the acceleration due to gravity, P is the pressure, is the stress tensor of the Newtonian fluid, The expression is as follows:

[0197]

[0198] Where μ is the dynamic viscosity;

[0199] Energy conservation equation:

[0200]

[0201] Where T is temperature, λ is thermal conductivity, c p is the specific heat capacity at constant pressure, S T is the source term;

[0202] Turbulence equation: Due to the complexity of the flow field in the cooling chamber, this paper adopts the SST k-ω turbulence model:

[0203]

[0204]

[0205] Where k is the turbulent kinetic energy, ω is the specific dissipation rate, ε is the turbulent dissipation rate, v t is the turbulent kinematic viscosity, u j (j=1,2,3) are velocity components, β, σ ω2 is a closed constant; F1 is a weighting function.

[0206] Preferably, the continuity equation of this embodiment ensures that the outflow rate in any given volume is equal to the inflow rate by expressing the continuity of mass during the fluid flow process, satisfying the principle of conservation of mass. Steady-state and non-steady-state analysis: provides a basis for flow analysis, can be used for the study of steady-state and transient flow, and ensures the reasonable distribution and flow of fluid in the equipment; basis of design: provides basic conditions for solving subsequent complex equations, and is the basis for flow simulation and analysis. The momentum conservation equation describes the momentum change of the fluid in time and space, taking into account the viscosity in fluid mechanics and the influence of external forces (such as gravity and pressure gradient) on the flow. Flow characteristic characterization: can fully understand the flow characteristics of each point in the flow field, such as velocity distribution, pressure changes, etc., which helps to design a system that better meets actual operating needs; optimize equipment design: through in-depth analysis of flow characteristics, the design parameters of equipment such as pipelines and valves can be optimized to improve the flow efficiency of the system and reduce energy losses. The energy conservation equation describes the heat change and transfer process in the fluid, including the influence of convection, heat conduction and heat source terms; thermal efficiency prediction: it can well predict the heat transfer efficiency of the fluid, ensure that the preheating system can achieve the design goals, and optimize the utilization and recovery of thermal energy; system efficiency analysis: it provides data support for the distribution, transfer and loss of heat, and can be used to evaluate the energy consumption and thermal efficiency of the system and promote energy-saving design. The turbulence equation (SST k-ω model) can simulate complex turbulent phenomena in a refined manner and calculate how the turbulent kinetic energy (k) and specific dissipation rate (ω) change with time and position. True reproduction of actual flow: accurate representation of various flow conditions, especially in high-speed and complex flow conditions, can obtain more accurate flow characteristics; flow control and optimization design: through in-depth analysis of turbulence, it is possible to find design solutions that reduce losses, improve heat transfer efficiency and flow stability, thereby improving the overall performance of the system.

[0207] In summary, through the application of the above equations and models, the CFD refined iterative design method in this embodiment can achieve: Accurate design: Compared with empirical formula design, CFD can provide more detailed and accurate simulation of flow and heat exchange behavior, avoiding the roughness and uncertainty of traditional design; Comprehensive performance evaluation: A comprehensive analysis of system performance, including flow, heat transfer and their mutual influence, provides a solid theoretical basis for design optimization; Improve energy efficiency and safety: The refinement of the design can improve the energy efficiency of the equipment, reduce the risk of failure, improve operational safety, and ensure that it is still stable and reliable under harsh conditions such as high temperature and high pressure; Promote innovation and R&D: Provide a calculation basis for the research of new materials, new structures and new technologies, and promote the development of more efficient and environmentally friendly heat recovery technologies.

[0208] In summary, by comprehensively applying the above equations and models, this design method in this embodiment not only improves the theoretical and practical level of the high-temperature flue gas heat energy recovery system, but also promotes the development of industrial automation and intelligence, and contributes to future sustainable development.

[0209] like Figure 6 As shown, this embodiment also provides an embodiment of a high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace. In this embodiment, the high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace is applied to the high-temperature flue gas heat energy recovery and utilization method for a metallurgical furnace as in the above embodiment. The high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace includes a normal temperature gas phase feed 1, a compressor 2, an air preheater 3, supersaturated hot steam 4, a waste heat boiler 5, low-temperature flue gas 6, a pump 7, feed water 8, a generator 9, return water 10, concentrate 11, hot air 12, a spray gun 13, a metallurgical furnace 14, and high-temperature flue gas 15;

[0210] Among them, the compressor 2 is connected to the air preheater 3 through a pipeline, the air preheater 3 is connected to the waste heat boiler 5 through a pipeline, the pump 7 is connected to the air preheater 3 and the waste heat boiler 5 through a pipeline, the generator 9 is connected to the air preheater 3, and the spray gun 13 is connected to the compressor 2 and the metallurgical furnace 14; the boiler pipe is connected to the pump 7 upstream, and is spirally placed after entering the waste heat boiler 5, and enters the air preheater 3 downstream to heat the normal temperature gas phase feed 1. The normal temperature gas phase feed 1 enters the air preheater 3 through the compressor 2, and the heated hot air 12 directly enters the metallurgical furnace 14 through the spray gun 13. The high-temperature flue gas 15 generated during the smelting process of the metallurgical furnace 14 enters the waste heat boiler 5 through a pipeline. After the hot air in the boiler pipe heats the normal temperature gas phase feed 1, it is passed into the generator 9 through the boiler pipe. After the power generation is completed, the boiler pipe is connected to the pump 7 again to form a circulation structure;

[0211] Preferably, the working principle of this embodiment is as follows: the high-temperature flue gas 15 discharged from the metallurgical furnace 14 first enters the waste heat boiler 5, in which a boiler tube is arranged, and the boiler tube is connected to the upstream water pump 7, which is used to pump cooling water into the system to complete the cycle. Under the convection and radiation heating of the high-temperature flue gas 15, the liquid water in the boiler tube boils to form supersaturated hot steam 4. Subsequently, the supersaturated hot steam 4 is introduced into the air preheater 3 through the pipeline to heat the normal temperature gas phase feed 1. The compressor 2 is connected upstream of the normal temperature gas phase feed 1, and the spray gun 13 is connected downstream to directly spray the preheated hot air 12 into the metallurgical furnace 14. After the hot air 12 is discharged from the air preheater 3, it is still in a supersaturated state and is used to drive the downstream generator 9 to generate electricity. After releasing heat energy, the high-temperature steam is converted into liquid, and finally the return water 10 flows back into the water tank and is pumped into the waste heat boiler 5 again by the water pump 7 to form a complete cycle.

[0212] This embodiment can effectively recover the waste heat generated in the smelting process by introducing high-temperature flue gas 15 into the waste heat boiler 5, and heat the normal-temperature gas-phase feed 1 through the boiler, thereby enhancing the heat recovery capacity of the system; in the air preheater 3, the normal-temperature gas is pressurized by the compressor 2 and heated to become hot air 12, which is directly used to improve the combustion process of the metallurgical furnace 14, thereby optimizing the combustion efficiency; the waste heat is utilized in the generator 9 to realize the conversion of waste heat energy into electrical energy, which not only improves the self-sufficiency of the system, but also effectively alleviates the pressure of electricity demand; the circulation design of the pump 7 and the boiler system ensures the flow of liquid between the waste heat boiler and the air preheater, and the establishment of a short-circuit loop optimizes the use of resources to reduce losses; the hot air 12 is sprayed into the metallurgical furnace 14 through the spray gun 13, which significantly increases the temperature in the furnace, accelerates the metal smelting process, and reduces the use of fuel. The system can recycle the heat energy that may be wasted in the smelting process, and cooperate with the links of pressurization, heating and power generation to comprehensively improve the energy utilization rate of the entire metallurgical process and meet the needs of modern industry for energy efficiency improvement. Through the rational use of waste heat and efficient recovery mechanism, the dependence on external energy is significantly reduced, thereby reducing the overall operating cost and playing a positive role in improving the economic benefits of the enterprise. By reducing the waste heat generated in the metallurgical process, the emission of flue gas can be reduced, the environmental protection effect can be improved, which meets the current industrial production requirements that are limited by emission standards and promotes clean production.

[0213] This embodiment demonstrates a new idea for energy recovery and utilization in modern metallurgical production, which helps promote technological innovation and upgrading of production methods in the metallurgical industry, thereby enhancing the competitiveness of the entire industry. By achieving efficient recycling of resources, the device not only meets the needs of industrial production, but also moves towards a more environmentally friendly and sustainable production model, laying the foundation for future green manufacturing. Through the design and construction of the system, the high-temperature flue gas heat energy recovery and utilization device realizes the maximum recovery and utilization of heat energy in metallurgical furnaces, which not only improves the energy efficiency in the smelting process, but also reduces operating costs and environmental impacts. It has strong industrial application potential and sustainable development advantages. In this way, the device fully reflects the trend of pursuing energy recovery and utilization efficiency in modern metallurgical production, and promotes the green transformation and economic development of the industry.

[0214] In summary, this embodiment utilizes the superheated steam generated by the waste heat boiler, first to preheat the gaseous feed, and then to generate electricity; in this way, the initial temperature of the furnace intake air can be increased, reducing the consumption of fuel energy; at the same time, the high-temperature gas is beneficial to improving combustion efficiency, accelerating the melting speed of materials, and improving smelting efficiency.

[0215] Furthermore, if Figure 7As shown, the structure of the air preheater 3 in this embodiment includes a low-temperature gas-phase feed inlet 16, a guide plate 17, a high-temperature heat pipe 18, a preheater outer wall 19, a high-temperature gas-phase feed outlet 20, a sealing partition 21, a superheated steam outlet 22, a heat compensator 23, and a superheated steam inlet 24;

[0216] Among them, a superheated steam inlet 24 is provided at the bottom of the air preheater 3, and each superheated steam inlet 24 enters the air preheater 3 through the boiler tube and the heat compensator 23. A low-temperature gas-phase feed inlet 16 is provided at the bottom of the air preheater 3 and close to the top of the heat compensator 23. The bottom of the air preheater 3 is a superheated steam outlet 22, which is separated from the interior by a sealing partition 21, and guide plates 17 are staggeredly distributed inside. A high-temperature heat pipe 18 that passes through the interior of the air preheater 3 is installed near the outer wall 19 of the preheater, and a high-temperature gas-phase feed outlet is provided at the same side as the low-temperature gas-phase feed inlet 16, close to the bottom of the sealing partition 21;

[0217] Preferably, the low-temperature gas phase feed inlet 16 of this embodiment is the inlet of the air preheater, which is used to feed the low-temperature gas phase material into the preheater. The guide plate 17 is staggered inside the air preheater to effectively guide and divert the airflow to enhance the heat exchange efficiency. The high-temperature heat pipe 18 runs through the high-temperature heat pipe of the air preheater and is used to conduct heat from the heat source (such as superheated steam) to the low-temperature gas phase. The outer wall 19 of the preheater provides physical protection and is also part of the insulation design to reduce heat loss. The high-temperature gas phase feed outlet 20 is discharged here after the preheating treatment of the gas phase to achieve heat transfer and utilization. The sealing partition 21 separates the superheated steam from other airflows to prevent mixing and ensure the orderly and efficient transfer of the airflow. The superheated steam outlet 22 discharges the cooled superheated steam from the air preheater. The heat compensator 23 is used to adjust and compensate for the changes in the airflow at different temperatures and pressures to ensure the stability of the system. The superheated steam inlet 24 is used to introduce the superheated steam from the boiler system into the preheater to increase the internal temperature.

[0218] In this embodiment, when the air preheater 3 is working, the process is described as follows: the superheated steam introduced from the boiler system enters the heat compensator 23 through the inlet 24. The function of the heat compensator is to ensure that the temperature and pressure of the gas are stable when entering the air preheater; the superheated steam is introduced into the air preheater in the heat compensator 23, and then the heat is transferred through the high-temperature heat pipe 18. The design of the high-temperature heat pipe enables the heat to be efficiently transferred from the superheated steam to the surrounding gas; when the low-temperature gas phase material enters the air preheater through the low-temperature gas phase feed inlet 16, the guide plate 17 helps to evenly distribute the airflow, increasing the airflow. The contact area for heat exchange is increased, while avoiding air flow short circuit, thereby improving heat transfer efficiency; when the low-temperature gas phase flows through the inside of the air preheater, it absorbs heat from the high-temperature heat pipe and superheated steam, and the temperature rises significantly. This process is carried out under the control of the sealing partition 21 to ensure that the superheated steam is separated from other gases; after heat exchange, the preheated high-temperature gas phase is discharged through the high-temperature gas phase feed outlet 20, which is usually used for subsequent smelting processes or other heating needs; after using the energy of the superheated steam, the steam is discharged through the superheated steam outlet 22, which may be further used for other heat recovery or cooled and recycled.

[0219] The design of the air preheater in this embodiment significantly improves the heating efficiency of the gas by increasing the contact area of ​​the airflow, optimizing the flow direction and the heat transfer path. The role of the thermal compensator ensures that the equipment can operate stably under temperature and pressure fluctuations, thereby improving the reliability and efficiency of the entire energy recovery system. Through the efficient heat exchange mechanism, the thermal energy utilization efficiency of the system is significantly improved, which helps to reduce energy consumption in the metallurgical process, realize waste heat recovery and utilization, and ultimately improve the energy application efficiency of the entire metallurgical process.

[0220] The preheater of this embodiment adopts a vertical straight tube structure, that is, supersaturated water vapor is introduced from the bottom straight tube, flows out from the top of the straight tube to the steam concentration area, and finally flows out from the top channel; the low-temperature gas phase is introduced from the bottom side, and under the action of the guide plate, it stays in the preheater for a sufficient time, and finally flows out from the middle and upper side; the heat pipe is connected to the shell by welding, and a thermal compensator is installed on the shell to prevent the heat pipe from bending and deforming due to thermal expansion (see the attached schematic diagram for a specific diagram). Figure 8 -Attached Fig. 9 ); The thermal compensator is equipped with elastic elements, which can produce corresponding deformation when the pipeline expands or contracts, thereby compensating for the axial, lateral and angular displacement of the pipeline;

[0221] In summary, the air preheater of this embodiment determines the preheating effect and heat exchange efficiency to a large extent. When the pipeline expands due to temperature increase, the elastic element will be stretched; conversely, when the pipeline contracts due to temperature decrease, the elastic element will be compressed; the stress in the pipeline can be effectively dispersed to prevent pipeline damage caused by temperature changes, such as loosening, deformation or cracking.

[0222] like Fig.10 As shown, this embodiment provides an embodiment of an electronic device. In this embodiment, the electronic device 25 includes a processor 251 and a memory 252 coupled to the processor 251.

[0223] The memory 252 stores program instructions for implementing the method for recovering and utilizing heat energy of high-temperature flue gas of a metallurgical furnace according to any of the above-mentioned embodiments.

[0224] The processor 251 is used to execute the program instructions stored in the memory 252 to implement the high-temperature flue gas heat energy recovery and utilization device of the metallurgical furnace.

[0225] The processor 251 may also be referred to as a CPU (Central Processing Unit). The processor 251 may be an integrated circuit chip having the ability to process signals. The processor 251 may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0226] Further, Fig.11 The schematic diagram of the structure of the storage medium of an embodiment of the present application is that the storage medium 26 of the embodiment of the present application stores program instructions 261 that can implement all the above methods, wherein the program instructions 261 can be stored in the above storage medium in the form of a software product, including several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) or a processor to execute all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, or terminal devices such as a computer, a server, a mobile phone, and a tablet.

[0227] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0228] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional units. The above is only an implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly used in other related technical fields, is also included in the patent protection scope of the present invention.

[0229] The specific implementation methods of the invention are described in detail above, but they are only examples, and the invention is not limited to the specific implementation methods described above. For those skilled in the art, any equivalent modification or substitution of the invention is also within the scope of the invention, therefore, the equalization, modification, improvement, etc. made without departing from the spirit and principle of the invention should be included in the scope of the invention.

Claims

1. A method for recovering heat energy from high-temperature flue gas of a metallurgical furnace, characterized in that: The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace comprises: The high-temperature flue gas discharged from the kiln first enters the waste heat boiler, which is equipped with boiler pipes. The boiler pipes are connected to the upstream water pump to pump cooling water into the system to complete the circulation; Under the convection and radiation heating of the high-temperature flue gas, the liquid water in the boiler tube boils to form superheated steam, which is introduced into the preheater through the pipeline to heat the low-temperature gas-phase feed; The compressor is connected to the upstream of the low-temperature gas phase feed, and the spray gun is connected to the downstream. The preheated high-temperature gas phase is sprayed into the furnace through the spray gun. At this time, the high-temperature steam is still in a supersaturated state and is used to drive the downstream generator to generate electricity; After releasing heat energy, the high-temperature steam turns into liquid, and finally flows back into the water tank, and is pumped into the waste heat boiler again by the water pump, forming a complete cycle; The following steps are also included: After the compressor presses the low-temperature gas phase into the air preheater for heating, a temperature monitoring module is set between the air preheater and the spray gun to control the compressor pressure; The spray volume and spray angle of the spray gun are adjusted in real time through intelligent control algorithms to adapt to changes in temperature and pressure in the furnace; Use organic Rankine cycle to integrate with waste heat power generation unit to recover energy from high-temperature flue gas and superheated steam; establish scheduling and control strategies to enable waste heat power generation unit to operate under different loads and operating conditions.

2. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace according to claim 1, characterized in that: The process of boiler tube layout optimization includes: Collect basic parameters and operating conditions of the boiler, including fluid type, flow rate, temperature, heat load and material properties; use computer-aided software to design the geometric model of the boiler interior, including boiler tubes, flue gas channels and heat exchange areas; Import the geometric model into the computational fluid dynamics software, perform meshing, and generate the finite element mesh required for calculation; determine the temperature, pressure, and velocity of the inlet fluid, and set the discharge conditions and boundary conditions of the wall temperature; Run computational fluid dynamics software simulation and perform numerical calculations to obtain numerical solutions for fluid flow and heat exchange in the boiler, including velocity field, temperature field and pressure distribution; visualize the computational fluid dynamics software simulation results, and analyze the flow state and heat conduction effect of the fluid in the boiler through streamline diagrams, temperature cloud diagrams and pressure distribution diagrams; obtain different pipeline layout methods based on the analysis results, perform parameter sensitivity analysis, and evaluate the impact of each new layout on heat exchange efficiency and pressure loss; continue to perform multiple rounds of computational fluid dynamics software simulation and result analysis, and gradually optimize the boiler pipeline layout until the designed heat exchange efficiency and flow characteristics requirements are met.

3. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace according to claim 2, characterized in that: The process of meshing includes: Perform preliminary global meshing on the entire geometric model, set a coarse mesh, and perform local meshing at the boiler tube inlet / outlet, heat exchange area, and corners / joints; Check mesh quality indicators using CFD software tools such as unit angle distribution, unit ratio and mesh size variation; Export the mesh to a format recognized by the CFD software; generate the corresponding input file based on the mesh division.

4. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace according to claim 1, characterized in that: The process of regulating compressor pressure includes: A temperature monitoring module is provided to monitor the temperature of the heated hot air, establish a connection with the compressor, and preset a threshold value for the temperature sensor; The temperature monitoring module collects the hot air temperature data in the boiler tube and compares it with the preset threshold. Through comparison, if the collected temperature reaches or exceeds the set temperature threshold, the compressor pressure is kept unchanged; if the collected temperature is lower than the preset temperature threshold, the compressor reduces the pressure; The results are monitored according to the temperature in the metallurgical furnace, and the compressor pressure and the set temperature threshold are regulated.

5. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace according to claim 1, characterized in that: The process of intelligent control algorithm adjusting the spray volume and spray angle of the spray gun in real time includes: Establish a temperature and pressure sensor network to continuously monitor the temperature and pressure in the furnace and transmit real-time data to the control system; collect flow and fuel type sensor data at the same time; filter and process the data collected from the sensors to analyze the current operating status in the furnace, detect real-time changes in temperature and pressure, and compare them with the set target values; Using neural network intelligent control algorithm, the required spray volume and injection angle are determined according to real-time data; according to the changes in temperature and pressure in the furnace, the spray volume is automatically increased or decreased if the temperature is too high or too low; the change in injection angle will be adjusted according to the airflow characteristics of the flow field in the furnace to optimize the mixing of airflow and fuel; The calculated control instructions for spray volume and injection angle are sent to the spray gun control system; the spray gun adjusts the spray output and injection angle in real time according to the received instructions; after the nozzle is adjusted, the temperature and pressure changes in the furnace continue to be monitored in real time; the effects of changes in spray volume and injection angle are evaluated, and the combustion efficiency and emissions are analyzed to see if they meet the set requirements; if the situation still does not meet the preset target, the intelligent control algorithm will be adjusted again according to the current data to form a closed-loop control to ensure continuous optimization.

6. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace according to claim 1, characterized in that: The process of establishing a dispatch and control strategy, including: Install sensors on the waste heat generators to monitor key parameters such as temperature, pressure, flow, load and efficiency; upload real-time data to ensure that the dispatch strategy can be adjusted accordingly based on the latest operating conditions; Use historical data and category analysis methods, combined with the operating environment, to predict future load demand and the upcoming peak load period based on the production plan; implement mathematical optimization algorithms to formulate scheduling strategies and optimally adjust the operating mode of the waste heat generator set; Recover energy from high-temperature flue gas and superheated steam, and control the flow and temperature of the recovered fluid by adjusting pumps and valves; adopt the most suitable working mode under different working conditions to ensure the efficient operation of ORC; monitor the power generation efficiency and heat recovery efficiency of ORC, evaluate the deviation from the preset standard, and adjust the fluid flow or equipment operating parameters based on the current load to optimize the overall system performance.

7. The method for recovering heat energy from high-temperature flue gas of a metallurgical furnace according to claim 1, characterized in that: The preheater pipeline arrangement inside the air preheater connected to the compressor, wherein the preheater pipeline arrangement adopts a 30° staggered arrangement; The process of obtaining the parameters of the high-temperature pipeline inside the air preheater connected to the air compressor specifically includes the following steps: different metallurgical furnaces have different preheating injection flow m and target temperature T o The requirements are different. After setting the target flow rate and temperature, the core parameters of the preheater need to be calculated to achieve the expected heat exchange effect. The core parameters include the number of pipes n, the outer diameter of the pipe d o , pipeline length L and pipeline spacing △; The target heat transfer capacity is determined according to the inlet and outlet temperatures and flow rates as follows: Q aim =Cp·m·(T o -T i ); Where Cp is the specific heat capacity, m is the target preheating mass flow rate, T o is the target temperature, T i is the intake air temperature; Actual heat exchange capacity: Q real =kAΔt; Where k is the heat transfer coefficient, A is the heat transfer area, and Δt is the average temperature difference between the two fluids; Among them, for the shell and tube structure, the value range of K is 5 to 35, and the middle value of 20 is taken as the initial design value, which is accurately evaluated through CFD calculation; the total heat exchange area A is: A=nπd o L; Where n is the number of heat pipes, d o is the outer diameter of the heat pipe, L is the length of the heat pipe; in the design process, the size parameters are initially determined based on the furnace size and heat exchange capacity. The heat pipe length is 2 to 3m, and the diameter range is 32-100mm. Based on this, the total number of heat pipes n is obtained; the spacing is 3 to 5 times d o , the overall size of the heat exchanger is obtained; the average temperature difference Δt is calculated by the following formula: in is the average temperature of the inlet and outlet steam, is the average temperature of the inlet and outlet air; The process of evaluating the global heat transfer effect of the air preheater includes: Construct a three-dimensional geometric model of the preheater according to the actual size, and distinguish between the fluid area and the solid area. The solid domain and the fluid domain are collectively referred to as the computational domain; discretize the computational domain into three-dimensional grids, and determine the grid quality through aspect ratio and twist angle parameters; determine the physical model and control equations to be solved, including the continuity equation, momentum equation, energy equation and turbulence equation; Given the mass flow rate and inlet temperature of high-temperature steam, the initial temperature and mass flow rate of low-temperature gaseous feed, the outlet static pressure of the high-temperature steam pipe, the static pressure of the gaseous feed outlet, and the interface between the fluid region and the solid region, the convection heat transfer coefficient is automatically calculated according to the flow velocity characteristics; Given the density of water vapor and low-temperature gas phase inlet, the ideal gas state equation is used to solve it, and the viscosity, thermal conductivity and specific heat capacity use the linear interpolation function of temperature; the pressure and velocity coupling method uses the SIMPLE algorithm, the convection term uses the second-order format discretization, and the pressure term uses the high-order format discretization; Given boundary conditions, physical properties and solution format, given initial field, start calculation, and monitor calculation until convergence; extract the temperature of gas phase feed outlet to evaluate whether the expected target temperature is reached; extract the gas phase feed inlet and outlet pressure drop to evaluate the upstream compressor pressure ratio and power; extract the steam outlet temperature to evaluate the downstream power generation capacity.

8. A device for recovering heat energy from high-temperature flue gas of a metallurgical furnace, which is applied to the method for recovering heat energy from high-temperature flue gas of a metallurgical furnace as claimed in any one of claims 1 to 7, characterized in that: The high-temperature flue gas heat energy recovery and utilization device of the metallurgical furnace comprises: a compressor, an air preheater, a waste heat boiler, a pump, a generator, a spray gun, a metallurgical furnace, and high-temperature flue gas; Among them, the compressor is connected to the air preheater through a pipeline, the air preheater is connected to the waste heat boiler through a pipeline, the pump is connected to the air preheater and the waste heat boiler through a pipeline, the generator is connected to the air preheater, and the spray gun is connected to the compressor and the metallurgical furnace.

9. The high-temperature flue gas heat energy recovery and utilization device for a metallurgical furnace according to claim 8, characterized in that: The air preheater includes a low-temperature gas phase feed inlet, a guide plate, a high-temperature heat pipe, a preheater outer wall, a high-temperature gas phase feed outlet, a sealing partition, a superheated steam outlet, a heat compensator, and a superheated steam inlet; Among them, a superheated steam inlet is arranged at the bottom of the air preheater, and each superheated steam inlet enters the interior of the air preheater through the boiler tube and the heat compensator. A low-temperature gas-phase feed inlet is opened at the bottom of the air preheater and close to the top of the heat compensator. The superheated steam outlet at the bottom of the air preheater is separated from the interior by a sealing partition, and guide plates are staggered inside. A high-temperature heat penetrating the interior of the air preheater is installed near the outer wall of the preheater, and a high-temperature gas-phase feed outlet is arranged on the same side as the low-temperature gas-phase feed inlet, close to the bottom of the sealing partition.

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