Step type industrial waste heat recycling method and device

Abstract

The invention provides a stepped industrial waste heat recycling method and device, and relates to the field of industrial energy conservation and waste heat recovery, the method comprises the following steps: obtaining waste heat resources with different temperature grades generated in an industrial production process, and carrying out grading pretreatment on the waste heat resources to obtain waste heat media of all grades meeting a preset clean standard; each stage of waste heat medium is guided into the corresponding heat exchange unit for heat exchange, and heat exchange media carrying different temperature grades are obtained; based on the temperature grade of each heat exchange medium, the heat exchange medium is distributed to the corresponding gradient utilization unit for energy utilization; and monitoring the waste heat load data and the user demand data in real time, and storing or releasing heat based on a comparison result of the waste heat load data and the user demand data. According to the system, full-temperature-section waste heat efficient recovery and gradient utilization are achieved, the energy utilization rate is increased, load fluctuation is adapted, the cost and carbon emission are reduced, and the environment-friendly requirement is met.

Description

Technical Field

[0001] This application relates to the field of industrial energy conservation and waste heat recovery, and more specifically, to a cascade industrial waste heat recovery and utilization method and apparatus. Background Technology

[0002] Industrial production processes generate a significant amount of waste heat, including high-temperature flue gas, process cooling water, and equipment surface heat dissipation, accounting for 30%-50% of total industrial energy consumption. Direct emissions not only cause serious energy waste but also exacerbate environmental thermal pollution. Effective recovery and utilization of industrial waste heat is a key path to achieving energy conservation and carbon reduction. Existing technologies are mostly single-stage waste heat recovery systems, targeting only a single temperature range and neglecting the value of medium- and low-temperature waste heat. Furthermore, these systems suffer from poor adaptability of heat exchange equipment, susceptibility to scaling and clogging, lagging control mechanisms, weak load adaptability, limited waste heat utilization methods, low system integration, and a lack of environmental protection treatment, making it difficult to meet the actual needs of multi-temperature range coverage, high recovery efficiency, and dynamic load adaptation. Summary of the Invention

[0003] The purpose of this application is to provide a cascade industrial waste heat recovery and utilization method and apparatus to solve the above-mentioned problems existing in the prior art, realize efficient recovery and cascade utilization of waste heat across the entire temperature range, improve recovery efficiency and energy value, enhance system stability, and reduce costs and carbon emissions.

[0004] Firstly, a cascaded industrial waste heat recovery and utilization method is provided, which may include: Waste heat resources with different temperature levels generated during industrial production are obtained, and the waste heat resources are pre-treated in stages to obtain waste heat media of various levels that meet preset cleanliness standards. Each level of waste heat medium is introduced into the corresponding heat exchange unit for heat exchange, resulting in heat exchange mediums carrying different temperature levels; Based on the temperature level of each heat exchange medium, it is allocated to the corresponding cascade utilization unit for energy utilization; Real-time monitoring of waste heat load data and user demand data, and heat storage or release based on the comparison results of the waste heat load data and user demand data.

[0005] In one possible implementation, waste heat resources with different temperature levels generated during industrial production are acquired, and the waste heat resources are subjected to graded pretreatment, including: High-temperature waste heat, medium-temperature waste heat, and low-temperature waste heat are obtained by setting up graded collection devices at different waste heat sources. The high-temperature waste heat is subjected to dust removal and desulfurization treatment, and the medium-temperature waste heat and the low-temperature waste heat are subjected to filtration and oil removal treatment.

[0006] In one possible implementation, the waste heat medium at each stage is introduced into the corresponding heat exchange unit for heat exchange, resulting in heat exchange mediums carrying different temperature levels, including: The pretreated high-temperature waste heat is introduced into the high-temperature heat exchange unit and exchanged with the first heat exchange medium to obtain the high-temperature heat exchange medium. The pretreated medium-temperature waste heat is introduced into the medium-temperature heat exchange unit and exchanged with the second heat exchange medium to obtain the medium-temperature heat exchange medium. The pretreated low-temperature waste heat is introduced into the low-temperature heat exchange unit and exchanged with the third heat exchange medium to obtain the low-temperature heat exchange medium.

[0007] In one possible implementation, based on the temperature level of each heat exchange medium, it is allocated to the corresponding cascade utilization unit for energy utilization, including: The high-temperature heat exchange medium is distributed to the power generation unit and / or the high-temperature process heating unit for use; The medium-temperature heat exchange medium is distributed to heating units and / or medium-temperature process heating units for use; The low-temperature heat exchange medium is distributed to the hot water supply unit and / or used as makeup water for the heating unit.

[0008] In one possible implementation, waste heat load data and user demand data are monitored in real time, and heat storage or release is performed based on the comparison results between the waste heat load data and user demand data, including: Real-time acquisition of waste heat load data reflecting the status of waste heat resources and user demand data reflecting energy consumption needs; The waste heat load data is compared with the user demand data to determine the supply-demand gap. When the supply-demand difference is greater than zero, the excess heat exchange medium is stored in the energy storage unit; When the supply-demand difference is less than zero, the energy storage unit is controlled to release the stored heat to supplement the supply.

[0009] In one possible implementation, the high-temperature waste heat has a temperature of 300 to 800 degrees Celsius, the medium-temperature waste heat has a temperature of 100 to 300 degrees Celsius, and the low-temperature waste heat has a temperature of 50 to 100 degrees Celsius.

[0010] In one possible implementation, the first heat exchange medium is heat transfer oil, and the second and third heat exchange media are water.

[0011] Secondly, a cascade-type industrial waste heat recovery and utilization device is provided, which may include: The acquisition unit is used to acquire waste heat resources with different temperature levels generated during industrial production, and to perform graded pretreatment on the waste heat resources to obtain waste heat media of various levels that meet preset cleanliness standards. The heat exchange unit is used to introduce the waste heat medium at each level into the corresponding heat exchange unit for heat exchange, so as to obtain heat exchange medium carrying different temperature levels. The distribution unit is used to allocate each heat exchange medium to the corresponding cascade utilization unit for energy utilization based on the temperature level of each heat exchange medium; The scheduling unit is used to monitor waste heat load data and user demand data in real time, and to store or release heat based on the comparison results of the waste heat load data and user demand data.

[0012] Thirdly, an electronic device is provided, which includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; When a processor executes a program stored in memory, it implements any of the steps described in the first aspect above.

[0013] Fourthly, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when executed by a processor, the computer program implements the steps of any of the methods described in the first aspect above.

[0014] This application provides a cascaded industrial waste heat recovery and utilization method and apparatus. The method includes: acquiring waste heat resources with different temperature levels generated during industrial production, and performing graded pretreatment on the waste heat resources to obtain waste heat media of various levels that meet preset cleanliness standards; introducing each level of waste heat media into corresponding heat exchange units for heat exchange to obtain heat exchange media carrying different temperature levels; distributing each heat exchange medium to corresponding cascade utilization units for energy utilization based on its temperature level; monitoring waste heat load data and user demand data in real time, and storing or releasing heat based on the comparison results between the waste heat load data and user demand data. This application achieves efficient recovery and cascaded utilization of waste heat across the entire temperature range, improves energy utilization efficiency, adapts to load fluctuations, reduces costs and carbon emissions, and meets environmental protection requirements. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A schematic flowchart of a cascade industrial waste heat recovery and utilization method provided for an embodiment of this application; Figure 2 A schematic diagram of a cascade industrial waste heat recovery and utilization device provided in this application embodiment; Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0018] Industrial production processes generate a significant amount of waste heat, including high-temperature flue gas, process cooling water, and equipment surface heat dissipation, accounting for 30%-50% of total industrial energy consumption. Direct emissions not only cause serious energy waste but also exacerbate environmental thermal pollution. Effective recovery and utilization of industrial waste heat is a key path to achieving energy conservation and carbon reduction. Existing technologies are mostly single-stage waste heat recovery systems, targeting only a single temperature range and neglecting the value of medium- and low-temperature waste heat. Furthermore, these systems suffer from poor adaptability of heat exchange equipment, susceptibility to scaling and clogging, lagging control mechanisms, weak load adaptability, limited waste heat utilization methods, low system integration, and a lack of environmental protection treatment, making it difficult to meet the actual needs of multi-temperature range coverage, high recovery efficiency, and dynamic load adaptation.

[0019] This application provides a cascaded industrial waste heat recovery and utilization method to solve the above-mentioned problems in the prior art. It can realize efficient recovery and cascaded utilization of waste heat across the entire temperature range, improve recovery efficiency and energy value, enhance system stability, and reduce costs and carbon emissions.

[0020] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application. Furthermore, the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0021] Figure 1 This is a schematic flowchart illustrating a cascaded industrial waste heat recovery and utilization method provided in an embodiment of this application. Figure 1 As shown, the method may include: Step S110: Obtain waste heat resources with different temperature levels generated during industrial production, and perform graded pretreatment on the waste heat resources to obtain waste heat media of various levels that meet the preset cleanliness standards.

[0022] Specifically, high-temperature, medium-temperature, and low-temperature waste heat are acquired through tiered collection devices installed at different waste heat sources. Furthermore, the high-temperature waste heat collection device employs a high-temperature resistant metal tube array structure, specifically installed at the flue gas outlet of industrial kilns to capture waste heat from high-temperature flue gas at 300-800℃. This device is equipped with a high-temperature thermocouple temperature sensor with a measurement range of 0-1000℃, enabling real-time monitoring of high-temperature waste heat temperature data and ensuring accurate perception of the high-temperature waste heat load. The medium-temperature waste heat collection device uses an immersion heat exchanger structure, installed at the cooling water outlet of process equipment, to capture medium-temperature waste heat at 100-300℃. The device is equipped with flow and temperature sensors, capable of simultaneously collecting the flow and temperature parameters of medium-temperature waste heat, comprehensively reflecting the load status of medium-temperature waste heat. The low-temperature waste heat collection device uses a heat pipe collection structure, installed on the heat dissipation area of ​​the equipment surface and at the low-temperature drain outlet, utilizing the efficient heat transfer characteristics of the heat pipe to efficiently capture waste heat from equipment surface heat dissipation at 50-100℃ and low-temperature drainage. The device is also equipped with temperature and flow sensors to enable real-time monitoring of low-temperature waste heat load data.

[0023] High-temperature waste heat undergoes dust removal and desulfurization treatment, while medium-temperature and low-temperature waste heat undergo filtration and oil removal treatment. Further, the high-temperature waste heat (high-temperature flue gas) enters a high-temperature pretreatment unit, which consists of a high-temperature dust collector and a desulfurization tower, employing a step-by-step process of dust removal and desulfurization: 1. Dust removal: The high-temperature flue gas is filtered through ceramic filter tubes in the high-temperature dust collector, removing ≥99% of the dust and preventing dust from adhering to the heat exchange surfaces of subsequent high-temperature heat exchange units, thus affecting heat exchange efficiency; 2. Desulfurization: The dust-removed high-temperature flue gas enters the desulfurization tower, where a limestone and gypsum method is used. Limestone slurry is sprayed to react chemically with SO2 in the flue gas, achieving a desulfurization efficiency of ≥95%, preventing sulfur-containing flue gas from corroding high-temperature heat exchange equipment, and simultaneously reducing pollutant emissions. Medium-temperature and low-temperature waste heat enter the medium- and low-temperature pretreatment device together. This device includes a filter purifier and an oil removal device, and adopts a purification process of filtration and oil removal. 1. Filtration treatment: The filter purifier with a filtration accuracy of ≥5μm removes solid impurities from the medium- and low-temperature waste heat medium (cooling water, equipment heat dissipation) to prevent impurities from depositing in the heat exchange channel and causing blockage. 2. Oil removal treatment: The adsorption-type oil removal device is used to remove oil from the filtered medium- and low-temperature waste heat medium. The oil removal efficiency is ≥98%, which effectively removes oil stains from the medium, prevents scaling on the surface of the heat exchanger, and ensures the stable operation of the heat exchange process.

[0024] In some embodiments, to ensure that the pretreatment effect meets the standards, this step is equipped with online monitoring instruments (including flue gas composition monitors and water quality monitors) to monitor in real time the dust content and SO2 concentration of the treated high-temperature flue gas, as well as the impurity content and oil content of the medium and low-temperature waste heat medium. If the monitoring results meet the preset cleanliness standards (dust content ≤10mg / m³, SO2 concentration ≤50mg / m³, impurity particle size ≤5μm, oil content ≤5mg / L), the clean waste heat medium at each stage enters the subsequent multi-stage heat exchange stage; if the monitoring results do not meet the standards, the central control unit will instruct the waste heat medium to return to the corresponding pretreatment device for reprocessing until the cleanliness standards are met before entering the next stage.

[0025] Step S120: Introduce the waste heat medium of each level into the corresponding heat exchange unit for heat exchange to obtain heat exchange medium carrying different temperature levels.

[0026] Among them, the high-temperature heat exchange unit adopts a shell-and-tube high-temperature heat exchanger with a heat exchange area of ​​50m² and a temperature tolerance of ≤1000℃, which can be adapted to the heat transfer requirements of high-temperature waste heat of 300-800℃; heat transfer oil is selected as the first heat exchange medium, which has a temperature tolerance of ≤350℃ and has the characteristics of strong high-temperature stability and high heat transfer efficiency, and can efficiently accept the heat of high-temperature waste heat.

[0027] The medium-temperature heat exchange unit adopts a plate heat exchanger with a heat exchange area of ​​30m² and a temperature tolerance of ≤350℃, which is suitable for heat exchange scenarios with medium-temperature waste heat of 100-300℃. Water is used as the second heat exchange medium, taking advantage of water's high specific heat capacity and good fluidity to achieve rapid transfer of medium-temperature waste heat. The equipment is also compact and easy to integrate into the system.

[0028] The low-temperature heat exchange unit adopts a heat pipe heat exchanger with a heat exchange area of ​​20m² and a temperature tolerance of ≤150℃. It addresses the pain point of low heat transfer efficiency of waste heat at low temperatures of 50-100℃ by leveraging the phase change heat transfer characteristics of the heat pipe to enhance the heat exchange effect. The third heat exchange medium is also water. Through the synergistic effect of the heat pipe and water, the bottleneck of low-temperature waste heat exchange is overcome.

[0029] Furthermore, each heat exchange unit is equipped with a temperature sensor, a pressure sensor, and a flow regulating valve to collect the temperature and pressure data of the medium during the heat exchange process in real time and upload the data to the central control unit to provide feedback signals for dynamic parameter adjustment. At the same time, safety valves and pressure relief valves are installed between each heat exchange unit and the heat storage device and the utilization loop to ensure that the system pressure is stable within a safe range.

[0030] Step S120 specifically includes: A. Introducing the pretreated high-temperature waste heat into the high-temperature heat exchange unit to exchange heat with the first heat exchange medium to obtain a high-temperature heat exchange medium; further, the high-temperature clean flue gas after dust removal and desulfurization treatment is introduced into the high-temperature heat exchange unit (shell-and-tube high-temperature heat exchanger) through a high-temperature conveying pipeline. The high-temperature flue gas flows in the shell side of the heat exchanger and exchanges heat with the first heat exchange medium (heat transfer oil) in the tube side. The high-temperature waste heat is transferred to the heat transfer oil through the tube wall, raising the temperature of the heat transfer oil to 280-320℃. The heat exchange efficiency of this heat exchange process is ≥92%. During the heat exchange process, if the high-temperature waste heat temperature suddenly changes (e.g., from 600℃ to 700℃), the central control unit immediately increases the heat transfer oil flow rate (increases by 10%-15%) based on the feedback signal from the temperature sensor to avoid the heat transfer oil overheating and damaging the equipment; if the waste heat temperature drops, the heat transfer oil flow rate is correspondingly reduced to ensure that the heat transfer oil temperature meets the standard.

[0031] B. The pretreated medium-temperature waste heat is introduced into the medium-temperature heat exchange unit to exchange heat with the second heat exchange medium, resulting in a medium-temperature heat exchange medium. Further, the filtered and degreased medium-temperature clean waste heat medium (cooling water, equipment heat dissipation) is introduced into the medium-temperature heat exchange unit (plate heat exchanger). The medium-temperature waste heat medium and the second heat exchange medium (water) flow counter-currently between the heat exchanger plates, rapidly transferring heat through the plates to raise the circulating water temperature to 80-100℃, with a heat exchange efficiency ≥90%. A pressure sensor monitors the pressure inside the heat exchanger in real time. If the pressure exceeds a set threshold, the pressure relief valve automatically opens to release pressure, ensuring a safe and stable heat exchange process.

[0032] C. The pretreated low-temperature waste heat is introduced into the low-temperature heat exchange unit to exchange heat with the third heat exchange medium, resulting in a low-temperature heat exchange medium. Further, the pretreated, clean low-temperature waste heat medium is introduced into the low-temperature heat exchange unit (heat pipe heat exchanger). Utilizing the phase change (evaporation-condensation) characteristics of the working fluid inside the heat pipe, it rapidly absorbs the heat from the low-temperature waste heat and transfers it to the third heat exchange medium (water) flowing outside the pipe, raising the water temperature to 45-60℃ with a heat exchange efficiency ≥88%. When the low-temperature waste heat temperature drops to a lower level such as 55℃, the central control unit adjusts the circulating water flow rate (reduction of 8%-12%) based on sensor data to ensure that the water temperature after heat exchange meets subsequent utilization requirements.

[0033] During the multi-stage heat exchange process, the central control unit collects key parameters of each heat exchange unit at a frequency of 10Hz via a data acquisition module. These parameters include the inlet and outlet temperatures and flow rates of the waste heat medium, the inlet and outlet temperatures and pressures of the heat exchange medium, and the operating status data of the heat exchangers. The logic processing module, based on a built-in heat exchange parameter optimization algorithm, analyzes the collected data in real time and dynamically adjusts the opening of the flow regulating valves and the speed of the delivery pumps in each heat exchange unit to ensure that the temperature of the heat exchange medium at each stage remains stable within the set range (high-temperature heat transfer oil 280-320℃, medium-temperature hot water 80-100℃, low-temperature hot water 45-60℃). Simultaneously, the online monitoring instrument monitors the quality of the heat exchange medium in real time. If deterioration of the heat transfer oil or exceeding water quality standards is detected, an alarm is immediately triggered, prompting maintenance to ensure the continuous and efficient operation of the heat exchange process.

[0034] Through the aforementioned graded and adaptive heat exchange design and dynamic control mechanism, this step achieves efficient conversion of waste heat at different temperature levels, providing a stable and energy-sufficient heat transfer medium for subsequent cascade utilization, while avoiding problems such as low heat exchange efficiency and high equipment wear caused by a single heat exchange structure.

[0035] Step S130: Based on the temperature level of each heat exchange medium, allocate it to the corresponding cascade utilization unit for energy utilization.

[0036] Specifically, A) the high-temperature heat exchange medium is distributed to the power generation unit and / or the high-temperature process heating unit for utilization; further, the power generation unit (waste heat power generation device) is directly connected to the high-temperature heat exchange unit, adopting an organic Rankine cycle power generation system with a rated power of 500kW, suitable for the energy level of 280-320℃ high-temperature heat transfer oil, which can efficiently convert high-grade heat energy into electrical energy with a power generation efficiency ≥18%; the power generation unit is equipped with a grid-connected control module, and the generated electricity can be flexibly connected to the factory's internal power grid for use by production equipment. The high-temperature process heating unit (process heating circuit) is connected to the high-temperature heat exchange unit and the medium-temperature heat exchange unit respectively, suitable for the energy supply needs of high-temperature heat transfer oil (280-320℃) and medium-temperature hot water (80-100℃), and is used for high-temperature process scenarios such as raw material preheating and reactor heating in industrial production; the circuit is equipped with a temperature regulating valve and a flow sensor, which can dynamically adjust the medium supply according to the process set temperature (such as the reactor set value of 250℃) to ensure that the process temperature fluctuation is ≤±2℃.

[0037] In some embodiments, the 280-320℃ heat transfer oil (high-temperature heat exchange medium) output by the high-temperature heat exchange unit is transported to the distribution node by a high-temperature heat transfer oil circulation pump (supporting variable frequency speed regulation, flow rate adjustment range 0-50m³ / h), and bidirectionally distributed according to real-time energy demand: When the factory has a high internal electricity demand or the grid electricity price is advantageous, some of the high-temperature heat transfer oil is introduced into the waste heat power generation device. The organic working medium is heated to evaporate and drives the turbine to rotate to generate electricity. The low-temperature organic working medium generated during the power generation process is condensed and recycled. The heat transfer oil releases heat and returns to the high-temperature heat exchange unit to absorb heat again. When there are high-temperature process requirements in industrial production (such as raw material preheating and constant temperature heating of reaction vessels), another part of the high-temperature heat transfer oil is directly connected to the process heating circuit. The flow rate is controlled by the temperature regulating valve to provide stable heat energy for the process equipment. After heat exchange, the temperature of the heat transfer oil drops to 150-200℃ and is returned to the high-temperature heat exchange unit for reheating via the circulation pump. The central control unit dynamically adjusts the medium distribution ratio for power generation and process heating based on data from waste heat load sensors and user demand monitoring modules. When the high-temperature waste heat load is sufficient, it can meet both needs simultaneously. When the waste heat load is insufficient, it prioritizes ensuring the heating needs of critical processes.

[0038] B. Distribute the medium-temperature heat exchange medium to the heating unit and / or the medium-temperature process heating unit for use; furthermore, the heating unit (heating circuit) connects the medium-temperature heat exchange unit and the low-temperature heat exchange unit, using 80-100℃ medium-temperature hot water as the main energy supply medium and 50-60℃ low-temperature hot water as a supplement to provide heating services for factory office buildings, dormitories and other buildings; the circuit is equipped with a flow regulating pump and an indoor temperature monitoring point, which can accurately adjust the hot water flow according to the indoor temperature setting requirement of 18-22℃ to achieve on-demand heating.

[0039] In some embodiments, the 80-100℃ hot water (medium-temperature heat exchange medium) output by the medium-temperature heat exchange unit is transported to the distribution nodes of the heating circuit and the process heating circuit via a medium-low temperature hot water circulation pump. As the main energy source for building heating, medium-temperature hot water is delivered to the heating system of each building via a flow regulating pump. The hot water flow is dynamically adjusted based on data from indoor temperature sensors to ensure that the indoor temperature is maintained at 18-22℃. After heat exchange, the hot water temperature drops to 40-50℃ and flows back to the medium-temperature heat exchange unit for reheating. When the process heating demand of industrial production exceeds the supply capacity of high-temperature heat transfer oil, some medium-temperature hot water is switched into the process heating circuit through valve switching as a supplementary heat source for high-temperature heat transfer oil, thereby improving the total energy supply capacity of process heating. In extreme situations such as a 30% increase in winter heating demand, the central control unit increases the circulating water flow of the medium-temperature heat exchange unit and simultaneously releases the stored medium-temperature hot water from the medium-low temperature hot water storage tank to ensure that heating demand is met. When process heating demand decreases, the medium distribution ratio of the heating circuit is increased to avoid energy waste.

[0040] C. Distribute the low-temperature heat exchange medium to the hot water supply unit and / or use it as makeup water for the heating unit; furthermore, the hot water supply unit (hot water supply circuit) is connected to the low-temperature heat exchange unit and equipped with a 50m³ hot water storage tank to store low-temperature heat exchange hot water at 45-60℃, providing domestic hot water for factory employee dormitories, bathrooms, etc.; the hot water storage tank has a built-in temperature sensor and insulation layer. When the water temperature is below 45℃, the system automatically starts the low-temperature heat exchange unit to supplement heat and maintain a stable water temperature; at the same time, the hot water supply circuit is reserved with a makeup water interface for the heating circuit, and the softened low-temperature hot water can be used as a makeup water source for the heating system.

[0041] In some embodiments, the 45-60℃ hot water (low-temperature heat exchange medium) output by the low-temperature heat exchange unit is mainly used for domestic hot water supply and heating circuit makeup water: The hot water storage tank, which introduces low-temperature hot water into the hot water supply circuit, stores the water through an insulation layer (heat loss rate ≤3% / 24h) to provide constant-temperature domestic hot water for employee dormitories, bathrooms, etc. The temperature sensor in the hot water storage tank monitors the water temperature in real time. When the water temperature is below 45℃, the central control unit automatically starts the low-temperature heat exchange unit to increase the heat exchange load of low-temperature waste heat and supplement the heat to the set temperature. Some of the low-temperature hot water is softened to remove calcium and magnesium ions before being injected into the heating circuit as a makeup water source. This prevents untreated water from causing scale buildup and blockage in the heating pipes, ensuring the long-term stable operation of the heating system. During the makeup water process, a level sensor monitors the water volume in the heating circuit in real time. When the water volume is lower than the set threshold, the makeup water process is automatically started to ensure sufficient water supply in the circuit.

[0042] Step S140: Monitor waste heat load data and user demand data in real time, and store or release heat based on the comparison results of waste heat load data and user demand data.

[0043] Specifically, step 1 involves real-time acquisition of waste heat load data reflecting the status of waste heat resources and user demand data reflecting energy consumption. Specifically, waste heat load sensors (temperature sensors, flow sensors) installed at the outlets of each waste heat collection device collect key parameters of each level of waste heat in real-time at a frequency of 10Hz: temperature and flue gas flow rate for high-temperature waste heat (300-800℃), temperature and medium flow rate for medium-temperature waste heat (100-300℃), and temperature and heat dissipation / drainage flow rate for low-temperature waste heat (50-100℃). The data acquisition module integrates and calculates the above parameters to obtain waste heat load data (unit: kW) reflecting the total amount and energy quality of waste heat resources, which is then uploaded to the central control unit in real-time. Simultaneously, user demand monitoring modules installed in each stage of the utilization loop collect dynamic demand data from the energy consumption end: electricity load demand of the waste heat power generation unit, set temperature and heat demand of the process heating loop, indoor temperature setpoint and building heat load of the heating loop, and water consumption and temperature demand of the hot water supply loop. Based on the operating status of each utilization unit (such as whether it is operating at full load or whether there is new energy demand), the real-time total user demand data (unit: kW) is calculated and uploaded to the central control unit.

[0044] Subsequently, the central control unit verifies the collected waste heat load data and user demand data in real time. It corrects the waste heat load calculation results by using the medium quality data (such as the purity of pretreated flue gas and the water quality of the heat exchange medium) fed back by the online monitoring instrument, so as to avoid load misjudgment caused by fluctuations in medium quality. For monitoring data that is temporarily missing, it uses historical similar operating condition data for interpolation to complete the data, so as to ensure the continuity and accuracy of supply and demand judgment.

[0045] Step 2: Compare the waste heat load data with user demand data to determine the supply-demand gap; specifically, based on the energy balance principle, the real-time waste heat load data ( ) and total user demand data ( Perform interpolation to obtain the supply-demand difference. .in, It is necessary to convert the waste heat of each level into a standard energy value based on the temperature level (e.g., high-temperature waste heat is converted according to the actual calorific value coefficient, and medium- and low-temperature waste heat is converted according to the corresponding heat exchange efficiency). The calculation should be weighted based on the energy priority of each utilization unit (process heating > power generation > heating > hot water supply) to ensure that the difference calculation is consistent with the actual energy consumption scenario.

[0046] When the supply-demand difference is greater than zero, the excess heat exchange medium is stored in the energy storage unit; that is, when When the waste heat load exceeds user demand, it is determined to be an oversupply, and the heat storage mode is activated: the central control unit instructs the corresponding heat exchange medium to be transported to the intelligent energy storage unit for storage based on the temperature level of the excess heat, until... Approaching 0 or the energy storage unit reaches its maximum storage capacity; When the supply-demand difference is less than zero, the energy storage unit is controlled to release the stored heat to supplement the supply. That is, when... When the waste heat load is lower than the user demand, it is determined to be a supply shortage, and the heat release mode is activated: the central control unit instructs the intelligent energy storage unit to release the stored heat at the corresponding temperature to supplement the corresponding utilization circuit, until the waste heat load is lowered to the user demand. Approaching zero or the energy storage unit depletes its stored heat; In some embodiments, when When supply and demand are basically balanced, the current operating status will be maintained, the energy storage unit will remain on standby, and data changes will be continuously monitored to be ready to respond to supply and demand fluctuations at any time.

[0047] When the high-temperature waste heat load is excessive, the central control unit instructs the diversion valve at the outlet of the high-temperature heat exchange unit to open, transferring high-temperature heat transfer oil (280-320℃) to a high-temperature storage tank (100m³). The high-temperature storage tank uses a composite insulation layer of aluminum silicate fiber cotton and polyurethane foam, with a thermal conductivity of 0.03W / (m²). K), heat loss rate ≤2% / 24h; the tank is equipped with temperature sensor and liquid level sensor to monitor storage temperature and oil volume in real time. When the heat transfer oil temperature reaches 320℃ or the liquid level reaches the maximum volume, the storage valve is closed and storage is stopped.

[0048] When the low-temperature waste heat load is excessive, the diversion valve at the outlet of the medium-temperature / low-temperature heat exchange unit is opened, and medium-temperature hot water (80-100℃) and low-temperature hot water (45-60℃) are uniformly transported to the medium-low temperature hot water storage tank (200m³). The water tank is insulated with polyurethane, with a heat loss rate of ≤3% / 24h. It has built-in temperature and liquid level sensors, and storage stops when the water temperature reaches 60℃ or the liquid level is full.

[0049] Both the high-temperature thermal storage tank and the medium-low temperature hot water storage tank are equipped with safety valves and pressure relief valves. When the pressure inside the tank exceeds the set threshold (≤1.2MPa for high-temperature thermal storage tank and ≤0.8MPa for medium-low temperature hot water storage tank), the safety valve will automatically release pressure to prevent the equipment from being damaged by overpressure. The temperature sensor monitors the temperature of the storage medium in real time. If an abnormal temperature rise occurs, an alarm will be triggered immediately and cooling emergency measures will be initiated.

[0050] When there is a shortage of high-temperature energy demand (such as increased demand for process heating or power generation), the central control unit instructs the outlet valve of the high-temperature thermal storage tank to open. The stored high-temperature thermal oil is then transported to the high-temperature heat exchange unit for secondary heat exchange via a high-temperature thermal oil circulation pump (supporting variable frequency speed control, flow rate adjustment range 0-50 m³ / h), or directly connected to the process heating circuit to supplement energy supply. During the release process, the pump speed is adjusted according to user needs to control the thermal oil flow rate and ensure stable energy supply.

[0051] When there is a shortage of energy demand in low-temperature environments (such as increased heating demand or insufficient hot water supply), the outlet valve of the low-temperature hot water storage tank is opened, and the stored hot water is replenished to the heating circuit or hot water supply circuit through the low-temperature hot water circulation pump. For example, when heating demand increases by 30% in winter, medium-temperature hot water (80-100℃) is released first to directly supplement the heating; when the hot water supply is insufficient, low-temperature hot water (45-60℃) is released to supplement the hot water storage tank.

[0052] During the heat release process, the central control unit synchronously adjusts the operating parameters of the corresponding heat exchange unit (such as heat exchange medium flow rate and temperature threshold) to make the released heat and the real-time waste heat load complement each other, avoiding temperature exceedance or supply-demand imbalance caused by the superposition of energy supply.

[0053] In a specific example, the central control unit updates supply and demand data at a frequency of 10Hz, adjusting the supply-demand gap and scheduling strategy in real time. For instance, when the waste heat load suddenly increases from 600℃ to 750℃, causing... When the demand increases significantly, the system should respond within 3 seconds, simultaneously increasing the high-temperature heat transfer oil storage flow rate (by 15%-20%) to avoid heat waste; when user demand suddenly decreases... When the signal changes from negative to positive, it immediately switches to storage mode and stores the excess heat in the energy storage unit.

[0054] When the energy storage unit's storage capacity is insufficient or the released heat still cannot meet the demand, priority scheduling is initiated: prioritizing the energy needs of process heating and core production, appropriately reducing the load distribution of heating and hot water supply, or tapping the potential of waste heat through heat exchange parameter optimization (such as improving heat exchange efficiency) to ensure that critical energy use is not affected.

[0055] Record the entire process data of energy storage scheduling (storage period ≥ 1 year), including the supply and demand difference change curve, the storage / release volume of energy storage units, and the operation parameter adjustment records, which facilitates subsequent analysis of waste heat supply and demand patterns and optimization of scheduling algorithms. At the same time, the temperature, liquid level, pressure and other statuses of energy storage units are displayed in real time through a human-machine interface, supporting manual intervention by staff (such as emergency stop of storage / release, adjustment of storage thresholds), ensuring that the scheduling process is safe and controllable.

[0056] Through the collaborative design of supply and demand monitoring, intelligent decision-making, hierarchical storage, and precise release, this step effectively solves the problem of temporal and spatial mismatch between waste heat supply and energy demand, improves the flexibility and reliability of waste heat resource utilization, and ensures the stable operation of energy storage and dispatch through a sound safety protection mechanism.

[0057] After passing through the low-temperature heat exchange unit, the exhaust gas is introduced into the exhaust gas treatment device via a dedicated pipeline for final pollutant purification. The exhaust gas treatment device targets residual trace dust and harmful gases (such as incompletely removed SO2 and volatile organic compounds) in the low-temperature exhaust gas, employing a combination of adsorption filtration and catalytic oxidation processes to further reduce pollutant emission concentrations. After treatment, the dust content of the exhaust gas is ≤5mg / m³, and the SO2 concentration is ≤35mg / m³, all meeting industrial waste gas emission standards. The exhaust gas treatment device is equipped with an online monitoring instrument to monitor the pollutant concentration in the emitted exhaust gas in real time. If the monitoring data exceeds the standard, an alarm is immediately triggered, and the central control unit is activated to adjust system operating parameters (such as increasing the purification intensity of the pretreatment device) to ensure that the exhaust gas always meets emission standards.

[0058] In some embodiments, when the system needs to be shut down, the central control unit issues a shutdown command, first stopping the operation of each level of waste heat collection device and closing the medium inlet valves of the high temperature and medium and low temperature pretreatment devices; Keep the conveying system and heat exchange unit running at low load. After the temperature of the heat exchange medium drops to a safe range (high temperature heat transfer oil ≤100℃, medium and low temperature hot water ≤40℃), shut down the high temperature, medium temperature, and low temperature heat exchange units and the conveying system (high temperature heat transfer oil circulation pump, medium and low temperature hot water circulation pump) in sequence. The intelligent energy storage unit maintains a thermal insulation state and records the storage temperature and liquid level data when it is shut down, reserving the initial state for the next startup. Activate the enhanced treatment mode of the exhaust gas treatment device to perform final purification treatment on the residual exhaust gas in the system. After the online monitoring instrument shows that the exhaust gas meets the emission standards, turn off the exhaust gas treatment device. The central control unit automatically stores the entire process data of this operation cycle (including waste heat recovery, energy utilization efficiency, equipment operating parameters, fault records, etc.) for a period of ≥1 year, which facilitates subsequent traceability and optimization; shutting down the operation module of the central control unit completes the system shutdown operation.

[0059] This application provides a cascaded industrial waste heat recovery and utilization method. The method includes: acquiring waste heat resources with different temperature levels generated during industrial production; pre-treating the waste heat resources in stages to obtain waste heat media of various levels that meet preset cleanliness standards; introducing each level of waste heat media into corresponding heat exchange units for heat exchange to obtain heat exchange media carrying different temperature levels; allocating each heat exchange medium to corresponding cascade utilization units for energy utilization based on its temperature level; and monitoring waste heat load data and user demand data in real time, and storing or releasing heat based on the comparison results between the waste heat load data and user demand data. This application achieves efficient recovery and cascaded utilization of waste heat across the entire temperature range, improves energy efficiency, adapts to load fluctuations, reduces costs and carbon emissions, and meets environmental protection requirements.

[0060] Corresponding to the above method, embodiments of this application also provide a cascade industrial waste heat recovery and utilization device, such as... Figure 2 As shown, the device includes: The acquisition unit 210 is used to acquire waste heat resources with different temperature levels generated during industrial production, and to perform graded pretreatment on the waste heat resources to obtain waste heat media of various levels that meet preset cleanliness standards. The heat exchange unit 220 is used to introduce the waste heat medium of each level into the corresponding heat exchange unit for heat exchange, so as to obtain heat exchange medium carrying different temperature levels. The distribution unit 230 is used to distribute each heat exchange medium to the corresponding cascade utilization unit for energy utilization based on the temperature level of each heat exchange medium. The scheduling unit 240 is used to monitor waste heat load data and user demand data in real time, and to store or release heat based on the comparison results of the waste heat load data and user demand data.

[0061] The functions of each functional unit of the cascade industrial waste heat recovery and utilization device provided in the above embodiments of this application can be realized through the above-described methods and steps. Therefore, the specific working process and beneficial effects of each unit in the cascade industrial waste heat recovery and utilization device provided in the embodiments of this application will not be repeated here.

[0062] This application also provides an electronic device, such as... Figure 3 As shown, it includes a processor 310, a communication interface 320, a memory 330, and a communication bus 340, wherein the processor 310, the communication interface 320, and the memory 330 communicate with each other through the communication bus 340.

[0063] Memory 330 is used to store computer programs; When the processor 310 executes the program stored in the memory 330, it performs the following steps: Waste heat resources with different temperature levels generated during industrial production are obtained, and the waste heat resources are pre-treated in stages to obtain waste heat media of various levels that meet preset cleanliness standards. Each level of waste heat medium is introduced into the corresponding heat exchange unit for heat exchange, resulting in heat exchange mediums carrying different temperature levels; Based on the temperature level of each heat exchange medium, it is allocated to the corresponding cascade utilization unit for energy utilization; Real-time monitoring of waste heat load data and user demand data, and heat storage or release based on the comparison results of the waste heat load data and user demand data.

[0064] The communication bus mentioned above can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0065] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0066] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0067] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0068] The implementation methods and beneficial effects of the various components of the electronic device in the above embodiments for solving the problem can be found in [reference needed]. Figure 1 The steps in the illustrated embodiments are used to implement the electronic device. Therefore, the specific working process and beneficial effects of the electronic device provided in this application will not be repeated here.

[0069] In another embodiment provided in this application, a computer-readable storage medium is also provided, which stores instructions that, when executed on a computer, cause the computer to perform any of the above embodiments of a cascade industrial waste heat recovery and utilization method.

[0070] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute any of the above embodiments of a cascade industrial waste heat recovery and utilization method.

[0071] Those skilled in the art will understand that the embodiments in this application can be provided as methods, systems, or computer program products. Therefore, the embodiments in this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the embodiments in this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0072] This application describes embodiments of methods, apparatus (systems), and computer program products according to embodiments of this application with reference to flowchart illustrations and / or block diagrams. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0073] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0074] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0075] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected," "coupled," or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0076] Although preferred embodiments have been described in this application, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the embodiments in this application are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments in this application.

[0077] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of the embodiments of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the embodiments of this application and their equivalents, then these modifications and variations are also intended to be included in the embodiments of this application.

Claims

1. A cascaded industrial waste heat recovery and utilization method, characterized in that, The method includes: Waste heat resources with different temperature levels generated during industrial production are obtained, and the waste heat resources are pre-treated in stages to obtain waste heat media of various levels that meet preset cleanliness standards. Each level of waste heat medium is introduced into the corresponding heat exchange unit for heat exchange, resulting in heat exchange mediums carrying different temperature levels; Based on the temperature level of each heat exchange medium, it is allocated to the corresponding cascade utilization unit for energy utilization; Real-time monitoring of waste heat load data and user demand data, and heat storage or release based on the comparison results of the waste heat load data and user demand data.

2. The method as described in claim 1, characterized in that, Acquire waste heat resources with different temperature levels generated during industrial production processes, and perform graded pretreatment on the waste heat resources, including: High-temperature waste heat, medium-temperature waste heat, and low-temperature waste heat are obtained by setting up graded collection devices at different waste heat sources. The high-temperature waste heat is subjected to dust removal and desulfurization treatment, and the medium-temperature waste heat and the low-temperature waste heat are subjected to filtration and oil removal treatment.

3. The method as described in claim 2, characterized in that, Each stage of waste heat medium is introduced into its corresponding heat exchange unit for heat exchange, resulting in heat exchange media carrying different temperature levels, including: The pretreated high-temperature waste heat is introduced into the high-temperature heat exchange unit and exchanged with the first heat exchange medium to obtain the high-temperature heat exchange medium. The pretreated medium-temperature waste heat is introduced into the medium-temperature heat exchange unit and exchanged with the second heat exchange medium to obtain the medium-temperature heat exchange medium. The pretreated low-temperature waste heat is introduced into the low-temperature heat exchange unit and exchanged with the third heat exchange medium to obtain the low-temperature heat exchange medium.

4. The method as described in claim 3, characterized in that, Based on the temperature level of each heat exchange medium, it is allocated to the corresponding cascade utilization unit for energy utilization, including: The high-temperature heat exchange medium is distributed to the power generation unit and / or the high-temperature process heating unit for use; The medium-temperature heat exchange medium is distributed to heating units and / or medium-temperature process heating units for use; The low-temperature heat exchange medium is distributed to the hot water supply unit and / or used as makeup water for the heating unit.

5. The method as described in claim 1, characterized in that, Real-time monitoring of waste heat load data and user demand data, and based on the comparison results of the waste heat load data and user demand data, performing heat storage or release, including: Real-time acquisition of waste heat load data reflecting the status of waste heat resources and user demand data reflecting energy consumption needs; The waste heat load data is compared with the user demand data to determine the supply-demand gap. When the supply-demand difference is greater than zero, the excess heat exchange medium is stored in the energy storage unit; When the supply-demand difference is less than zero, the energy storage unit is controlled to release the stored heat to supplement the supply.

6. The method as described in claim 2, characterized in that, The temperature of the high-temperature waste heat is 300 to 800 degrees Celsius, the temperature of the medium-temperature waste heat is 100 to 300 degrees Celsius, and the temperature of the low-temperature waste heat is 50 to 100 degrees Celsius.

7. The method as described in claim 3, characterized in that, The first heat exchange medium is heat transfer oil, and the second and third heat exchange media are water.

8. A cascade-type industrial waste heat recovery and utilization device, characterized in that, The device includes: The acquisition unit is used to acquire waste heat resources with different temperature levels generated during industrial production, and to perform graded pretreatment on the waste heat resources to obtain waste heat media of various levels that meet preset cleanliness standards. The heat exchange unit is used to introduce the waste heat medium at each level into the corresponding heat exchange unit for heat exchange, so as to obtain heat exchange medium carrying different temperature levels. The distribution unit is used to allocate each heat exchange medium to the corresponding cascade utilization unit for energy utilization based on the temperature level of each heat exchange medium; The scheduling unit is used to monitor waste heat load data and user demand data in real time, and to store or release heat based on the comparison results of the waste heat load data and user demand data.

9. An electronic device, characterized in that, The electronic device includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the steps of the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method described in any one of claims 1-7.

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