Continuous lime cooling method and system for double-loop waste heat recovery

Abstract

The invention relates to the technical field of lime cooling, and discloses a continuous lime cooling method and system for double-loop waste heat recovery. The method comprises the following steps: acquiring an initial temperature and a mass flow parameter of high-temperature lime at an outlet of a lime kiln, and extracting a target temperature threshold and a heat exchange medium basic parameter in a cooling process standard from a preset database; then, a double-loop waste heat recovery path comprising a main cooling loop and an auxiliary recovery loop is constructed, and based on the difference value between the initial temperature and the target temperature, the flow speed of the first type of media in the main loop and the flow of the second type of media in the auxiliary loop are dynamically regulated and controlled; the real-time temperature of the high-temperature lime in the main loop, the outlet temperature of the first type of media and the inlet and outlet temperature data of the second type of media in the auxiliary loop are collected in real time at the same time; and finally, judging whether the high-temperature lime meets a cooling standard corresponding to the target temperature or not according to the collected temperature data and a preset heat balance relationship. According to the method, efficient cooling and waste heat recovery are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lime cooling, in particular to a continuous lime cooling method and system with double-loop waste heat recovery. BACKGROUND

[0002] Lime is an important industrial raw material and is widely used in metallurgy, construction, chemical industry and many other fields. In the production process of lime, high-temperature lime at the outlet of the lime kiln usually needs to be cooled to meet the requirements of subsequent processing and use. However, the traditional lime cooling technology has many shortcomings. Most of the existing lime cooling methods use single-loop cooling systems. In the cooling process, the heat exchange efficiency between high-temperature lime and heat exchange medium is low, resulting in a large amount of waste heat that cannot be effectively recovered and utilized, causing energy waste.

[0003] The single-loop system cannot accurately control the flow rate and flow of the heat exchange medium according to the temperature change of the high-temperature lime, making the cooling process uneven and affecting the cooling quality of the lime. In addition, the pipeline structure design of the traditional cooling system is not reasonable, and the contact area between the heat exchange medium and the high-temperature lime is limited, further reducing the heat exchange efficiency. Moreover, the existing cooling system lacks real-time collection of temperature data and accurate determination of heat balance relationship during the cooling process, which cannot timely understand the cooling effect and cannot guarantee that the high-temperature lime reaches the target temperature threshold corresponding to the cooling standard.

[0004] With the continuous improvement of energy saving and product quality requirements in industrial production, the traditional lime cooling technology has been difficult to meet the needs of actual production, and a new type of lime cooling method and system that can improve waste heat recovery efficiency, achieve precise cooling and ensure cooling quality is urgently needed. SUMMARY

[0005] The purpose of the present application is to provide a continuous lime cooling method and system with double-loop waste heat recovery to solve the problems raised in the background art.

[0006] To achieve the above-mentioned purpose, the present application provides a continuous lime cooling method with double-loop waste heat recovery, which comprises: obtaining the initial temperature parameter and mass flow parameter of high-temperature lime at the outlet of the lime kiln, and synchronously extracting the target temperature threshold and heat exchange medium basic parameter in the lime cooling process standard from a preset database; constructing a double-loop waste heat recovery path comprising a main cooling loop and an auxiliary recovery loop, wherein the main cooling loop is used to bear the direct contact heat exchange process of high-temperature lime and the first type of heat exchange medium, and the auxiliary recovery loop is used to bear the indirect heat conduction process of the first type of heat exchange medium and the second type of heat exchange medium; Based on the difference between the initial temperature parameter and the target temperature threshold, the flow rate of the first type of heat exchange medium in the main cooling loop and the flow rate of the second type of heat exchange medium in the auxiliary recovery loop are dynamically controlled; Real-time collection of high-temperature lime temperature data in the main cooling circuit and outlet temperature data of the first type of heat exchange medium, and simultaneous collection of inlet and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery circuit; Based on the real-time collected temperature data and the preset heat balance relationship, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold; Among them, the flow rate of the first type of heat exchange medium in the main cooling circuit is dynamically controlled, including: based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the contact area ratio of the first type of heat exchange medium in different temperature sections is gradiently adjusted to obtain the medium flow rate segmentation control coefficient; based on the medium flow rate segmentation control coefficient, the initial flow rate of the first type of heat exchange medium is corrected to obtain the main cooling circuit medium control flow rate.

[0007] Preferably, a dual-circuit waste heat recovery path comprising a main cooling circuit and an auxiliary recovery circuit is constructed, including: The pipeline structure of the main cooling circuit is set as a spiral contact channel, and the pipeline structure of the auxiliary recovery circuit is set as a nested sleeve structure. The main cooling circuit outlet and the auxiliary recovery circuit inlet are sealed and connected through flange connection components to form a dual-circuit waste heat recovery path.

[0008] Preferably, based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the contact area ratio of the first type of heat exchange medium in different temperature sections is adjusted in a gradient manner to obtain a medium flow rate segmentation control coefficient, including: The spiral contact channel of the main cooling circuit is divided into sections to obtain a high-temperature section, a medium-temperature section, and a low-temperature section; The mass proportion of high-temperature lime in the high-temperature section, the medium-temperature section, and the low-temperature section is calculated to obtain the mass distribution data of each temperature section; Calculating the contact area adjustment amount for each temperature section based on the mass distribution data of each temperature section and the preset contact area reference value of the corresponding section to obtain the contact area ratio of the first type of heat exchange medium in different temperature sections; Based on the contact area ratio of each temperature section and the flow rate correction coefficient table of the corresponding section, the medium flow rate segment control coefficient is retrieved and summarized.

[0009] Preferably, the mass proportion of high-temperature lime in the high-temperature section, the medium-temperature section, and the low-temperature section is calculated to obtain mass distribution data of each temperature section, including: Mass sensors are arranged at the inlet, middle point and outlet positions of the spiral contact passage of the main cooling circuit, and the mass data of the lime at the positions are collected in real time by the mass sensors; The lime mass in the high-temperature section is calculated according to the difference between the mass data at the inlet and the middle point, the lime mass in the medium-temperature section is calculated according to the difference between the mass data at the middle point and the outlet, and the lime mass in the low-temperature section is calculated according to the mass data at the outlet position. The lime mass in each temperature section is divided by the total mass to obtain the mass proportion data of each temperature section.

[0010] Preferably, according to the mass distribution data of each temperature section and the preset contact area reference value of the corresponding section, the contact area adjustment amount of each temperature section is calculated to obtain the contact area proportion of the first type of heat exchange medium in different temperature sections, including: The preset contact area reference values of the high-temperature section, the medium-temperature section and the low-temperature section are obtained. The mass proportion data of each temperature section is multiplied by the preset contact area reference value of the corresponding section to obtain the contact area adjustment amount of each temperature section. The contact area adjustment amount of each temperature section is divided by the total contact area adjustment amount to obtain the contact area proportion of the first type of heat exchange medium in different temperature sections.

[0011] Preferably, based on the contact area proportion of each temperature section and the flow rate correction coefficient table of the corresponding section, the medium flow rate segmented control coefficient is obtained by searching and summarizing, including: The flow rate correction coefficients corresponding to the contact area proportions of the high-temperature section, the medium-temperature section and the low-temperature section are searched from the preset flow rate correction coefficient table. The contact area proportions of each temperature section are multiplied by the flow rate correction coefficients of the corresponding section, and then summed to obtain the medium flow rate segmented control coefficient.

[0012] Preferably, based on the medium flow rate segmented control coefficient, the initial flow rate of the first type of heat exchange medium is corrected to obtain the main cooling circuit medium control flow rate, including: The initial flow rate of the first type of heat exchange medium is multiplied by the medium flow rate segmented control coefficient, and the speed of the conveying equipment of the first type of heat exchange medium is adjusted by the flow control valve to output the main cooling circuit medium control flow rate.

[0013] Preferably, according to the real-time collected temperature data and the preset heat balance relationship, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold, including: The difference between the initial temperature and the real-time temperature of the high-temperature lime in the main cooling circuit is calculated to obtain the lime temperature drop value, and the difference between the outlet temperature and the inlet temperature of the first type of heat exchange medium is calculated to obtain the medium temperature rise value. Calculate the difference between the outlet temperature and the inlet temperature of the second type of heat exchange medium in the auxiliary recovery loop to obtain the temperature rise of the recovery medium; According to the proportional relationship between the lime temperature drop value, the medium temperature rise value and the recovered medium temperature rise value, combined with the preset thermal balance matching threshold, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold.

[0014] Preferably, according to the proportional relationship between the lime temperature drop value, the medium temperature rise value and the recovery medium temperature rise value, combined with a preset heat balance matching threshold, determining whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold includes: The ratio of lime temperature drop to medium temperature rise is defined as the primary heat exchange efficiency coefficient, and the ratio of medium temperature rise to recovered medium temperature rise is defined as the secondary heat recovery efficiency coefficient. If the primary heat exchange efficiency coefficient and the secondary heat recovery efficiency coefficient are both within the preset thermal balance matching threshold range, it is determined that the high-temperature lime meets the cooling standard corresponding to the target temperature threshold, otherwise it is determined that it does not meet the cooling standard.

[0015] Preferably, the present invention further includes a continuous lime cooling system with double-circuit waste heat recovery, which is used to implement the above-mentioned continuous lime cooling method with double-circuit waste heat recovery. The system includes: The parameter acquisition module is used to obtain the initial temperature parameters and mass flow parameters of the high-temperature lime at the lime kiln outlet, and simultaneously extract the target temperature threshold and basic parameters of the heat exchange medium in the lime cooling process standard from the preset database; A circuit construction module is used to construct a dual-circuit waste heat recovery path including a main cooling circuit and an auxiliary recovery circuit, wherein the main cooling circuit is used to carry out a direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, and the auxiliary recovery circuit is used to carry out an indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium; a medium control module for dynamically controlling the flow rate of the first type of heat exchange medium in the main cooling loop and the flow rate of the second type of heat exchange medium in the auxiliary recovery loop based on the difference between the initial temperature parameter and the target temperature threshold; The process monitoring module is used to collect the real-time temperature data of the high-temperature lime in the main cooling loop and the outlet temperature data of the first type of heat exchange medium, and simultaneously collect the inlet and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery loop; The effect determination module is used to determine whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold based on the real-time collected temperature data and the preset heat balance relationship.

[0016] Compared with the prior art, the present invention has the following beneficial effects: By constructing a dual-circuit waste heat recovery path consisting of a main cooling circuit and an auxiliary recovery circuit, the main cooling circuit carries out direct contact heat exchange between the high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery circuit facilitates indirect heat transfer between the first type of heat exchange medium and the second type of heat exchange medium. This dual-circuit design significantly improves waste heat recovery efficiency, allowing more heat to be reused and reducing energy consumption. Based on the difference between the initial temperature parameter and the target temperature threshold, the flow rate of the first type of heat exchange medium in the main cooling circuit and the flow rate of the second type of heat exchange medium in the auxiliary recovery circuit are dynamically controlled. This allows for flexible adjustments based on the actual temperature of the high-temperature lime, making the cooling process more precise and ensuring that the high-temperature lime is evenly cooled to the target temperature.

[0017] The piping structure of the main cooling circuit is configured as a spiral contact channel, and the auxiliary recovery circuit is configured as a nested sleeve structure, sealed with flanged connections. This structural design increases the contact area between the heat exchange medium and the high-temperature lime, optimizing the heat exchange process and further enhancing the heat exchange effect. When dynamically regulating the flow rate of the first type of heat exchange medium in the main cooling circuit, based on the real-time temperature distribution characteristics of the high-temperature lime, the contact area ratio of different temperature sections is gradiently adjusted to obtain the medium flow rate segmentation control coefficient, and the initial flow rate is then corrected. This segmented control method can more accurately adapt to the cooling needs of different temperature sections, improving the accuracy and effectiveness of cooling.

[0018] Real-time temperature data is collected from the main cooling circuit and auxiliary recovery circuit. Based on a preset thermal balance relationship, the system determines whether the high-temperature lime meets cooling standards. By calculating the proportional relationship between the lime temperature drop, the medium temperature rise, and the recovery medium temperature rise, and combining this with a thermal balance matching threshold, the system accurately assesses the cooling effect and ensures that the high-temperature lime meets cooling standards. The system includes a parameter acquisition module, a circuit construction module, a medium control module, a process monitoring module, and an effect determination module. These modules work together to automate and intelligently implement the lime cooling process, improving production efficiency and reducing labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a working principle diagram of the continuous lime cooling method with double-circuit waste heat recovery according to the present invention; Figure 2 A flow chart constructed for the dual-loop waste heat recovery pathway; Figure 3 This is a flow chart for calculating the medium flow rate segmented control coefficient; Figure 4 Flowchart for acquiring mass distribution data for temperature bins. DETAILED DESCRIPTION

[0020] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work are within the protection scope of the present application.

[0021] Please refer to Figure 1-Figure 4 The present application provides a continuous lime cooling method with double-loop waste heat recovery, and the specific implementation steps are as follows: The initial temperature parameter and mass flow parameter of high-temperature lime at the outlet of the lime kiln are obtained, and the target temperature threshold in the lime cooling process standard and the basic parameter of the heat exchange medium are extracted from the preset database at the same time. The initial temperature parameter is collected in real time by the temperature sensor arranged at the outlet of the lime kiln, and the mass flow parameter is obtained by the flowmeter installed at the outlet pipeline. The preset database stores the cooling process standards of different specifications of lime.

[0022] A double-loop waste heat recovery path including a main cooling loop and an auxiliary recovery loop is constructed. The main cooling loop is used to bear the direct contact heat exchange process of high-temperature lime and the first type of heat exchange medium, and the auxiliary recovery loop is used to bear the indirect heat conduction process of the first type of heat exchange medium and the second type of heat exchange medium.

[0023] Based on the difference between the initial temperature parameter and the target temperature threshold, the flow rate of the first type of heat exchange medium in the main cooling loop and the flow of the second type of heat exchange medium in the auxiliary recovery loop are dynamically regulated. Specifically, the control system calculates the regulation parameters according to the difference, and then controls the flow control valve and the rotating speed of the conveying equipment.

[0024] Real-time temperature data of high-temperature lime and outlet temperature data of the first type of heat exchange medium in the main cooling loop are collected in real time, and inlet temperature data and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery loop are collected at the same time. Each temperature data is collected by the corresponding temperature sensor and transmitted to the control system.

[0025] According to the real-time collected temperature data and the preset heat balance relationship, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold. The control system obtains the determination result by calculating the related temperature difference and the proportional relationship, and comparing with the preset threshold.

[0026] Among them, the flow rate of the first type of heat exchange medium in the main cooling circuit is dynamically controlled, including: based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the contact area ratio of the first type of heat exchange medium in different temperature sections is gradiently adjusted to obtain the medium flow rate segmentation control coefficient; based on the medium flow rate segmentation control coefficient, the initial flow rate of the first type of heat exchange medium is corrected to obtain the main cooling circuit medium control flow rate.

[0027] Example 1: In the process of constructing a dual-circuit waste heat recovery path, the pipeline structure of the main cooling circuit is set as a spiral contact channel. The specific structure of the spiral contact channel must meet the actual needs of the heat exchange process. For example, parameters such as the angle of the spiral, the pitch, and the diameter of the channel must be designed according to the heat exchange efficiency requirements of the high-temperature lime and the first type of heat exchange medium. The design of the spiral structure can effectively increase the flow path length of the high-temperature lime in the channel, thereby extending the contact time between the high-temperature lime and the first type of heat exchange medium. At the same time, the spiral channel layout also expands the contact area between the heat exchange medium and the lime, creating favorable conditions for sufficient heat exchange between the two.

[0028] The auxiliary recovery loop's piping is designed as a nested tube-in-tube structure. This structure consists of an inner tube and an outer tube. The inner tube is used to transport the first type of heat exchange medium flowing out of the main cooling loop, while the outer tube is used to transport the second type of heat exchange medium. The material selection for the inner and outer tubes must take into account factors such as thermal conductivity and corrosion resistance to ensure efficient heat transfer during the heat exchange process while also ensuring the service life of the pipes. The nested tube-in-tube design allows for indirect heat transfer between the first and second type of heat exchange media without direct contact, avoiding problems that may arise from mixing the two media.

[0029] The main cooling circuit outlet and the auxiliary recovery circuit inlet are sealed together via flange connections. The flange connections must be selected in accordance with relevant industry standards to ensure reliable sealing performance. When installing the flange connections, strict installation specifications must be followed, such as cleaning the flange surfaces, using appropriate sealing gaskets, and evenly tightening the bolts to ensure a tight seal at the connection and prevent leakage during the flow of the heat exchange medium. The sealed connection design enables the main cooling circuit and the auxiliary recovery circuit to form a complete dual-circuit waste heat recovery path, ensuring the continuity and stability of the heat exchange process.

[0030] In the main cooling circuit, high-temperature lime is in direct contact with the first type of heat exchange medium. The selection of the first type of heat exchange medium needs to consider its heat capacity, boiling point, and chemical stability, etc. to ensure that it can effectively absorb the heat of high-temperature lime. When high-temperature lime enters the spiral contact channel, it is fully mixed and contacted with the first type of heat exchange medium in the channel. The heat is transferred from the high-temperature lime to the first type of heat exchange medium, reducing the temperature of the lime, while the temperature of the first type of heat exchange medium rises.

[0031] In the auxiliary recovery circuit, the first type of heat exchange medium with increased temperature enters the inner tube of the nested sleeve structure and is in indirect heat conduction with the second type of heat exchange medium in the outer tube. The selection of the second type of heat exchange medium also needs to consider factors such as heat conduction performance and safety. The heat is transferred from the first type of heat exchange medium to the second type of heat exchange medium through the inner tube wall, increasing the temperature of the second type of heat exchange medium, while further reducing the temperature of the first type of heat exchange medium. After heat conduction through the auxiliary recovery circuit, the first type of heat exchange medium can be reused in the main cooling circuit, improving the utilization rate of the heat exchange medium.

[0032] The construction of the entire double-circuit waste heat recovery path needs to consider the matching and coordination of each part. For example, the size of the spiral contact channel of the main cooling circuit and the size of the nested sleeve structure of the auxiliary recovery circuit need to be designed according to the processing capacity of the lime, the initial temperature and the target temperature, etc. to ensure that the entire system can efficiently complete the cooling and waste heat recovery tasks. At the same time, the arrangement of the pipeline also needs to consider the space layout and the convenience of installation and maintenance, such as reserving enough space for the maintenance and replacement of the pipeline and equipment.

[0033] In addition, in the double-circuit waste heat recovery path, corresponding monitoring devices such as temperature sensors and flow sensors need to be set up to monitor the temperature and flow data of each part in real time. The installation position of these monitoring devices needs to accurately reflect the actual situation in the heat exchange process, providing reliable basis for subsequent medium regulation and effect determination. Temperature sensors can be installed at the inlet, middle and outlet positions of the main cooling circuit, as well as the inlet and outlet positions of the auxiliary recovery circuit to collect temperature data of high-temperature lime and heat exchange medium in real time. Flow sensors can be installed on the heat exchange medium conveying pipeline to monitor the flow of the first type of heat exchange medium and the second type of heat exchange medium.

[0034] During system operation, every step in the dual-circuit waste heat recovery path requires real-time monitoring and management. For example, if the heat exchange performance in the primary cooling circuit is poor, adjustments may be needed to the structural parameters of the spiral contact channel or the flow rate of the first type of heat exchange medium. If the heat transfer efficiency of the auxiliary recovery circuit decreases, the sealing of the nested casing structure or the performance of the second type of heat exchange medium may need to be checked.

[0035] The dual-circuit waste heat recovery path is constructed through the hardware components of the circuit construction module, which specifically includes: ① Main cooling circuit assembly: This is the aforementioned spiral contact channel (made of 304 stainless steel, with an inner diameter of 200mm and a pitch of 500mm, and the inner wall of the channel is sprayed with an aluminum oxide wear-resistant coating). Its function is to carry out the direct contact heat exchange process between the high-temperature lime and the first type of heat exchange medium (air); ② Auxiliary recovery circuit assembly: This is the aforementioned nested casing structure (the inner tube is a seamless steel pipe with an inner diameter of 150mm; the outer tube is a stainless steel pipe with an inner diameter of 250mm, and the gap between the inner and outer tubes is filled with aluminum silicate insulation wool). Its function is to carry out the indirect heat transfer process between the first type of heat exchange medium and the second type of heat exchange medium (thermal oil); ③ Connection component: This is the aforementioned flange connection component (model PN1.6MPa, made of 304 stainless steel, with a graphite composite gasket as the sealing gasket). Bolting ensures a sealed connection between the main cooling circuit outlet and the auxiliary recovery circuit inlet, ensuring that the dual-circuit media are leak-proof. The above components work together to form a dual-circuit waste heat recovery path, providing the hardware foundation for subsequent cooling and waste heat recovery.

[0036] Example 2: The flow rate control process of the first type of heat exchange medium is implemented by a medium control module, which includes: ① Control unit: using a Siemens S7-1200 PLC (equipped with an analog input / output module) with a built-in "medium flow rate segmented control coefficient calculation algorithm" for receiving temperature data and outputting control instructions; ② Main loop execution components: including a variable frequency blower (air volume adjustment range 0-10,000 m³ / h, power 15kW) and an electric flow control valve (model ZDLP-16C, adjustment accuracy ±1%), which adjust the flow rate of the first type of heat exchange medium (air) according to PLC instructions; ③ Auxiliary loop execution components: including a gear pump (flow adjustment range 0-50 m³ / h, power 7.5kW) and an electromagnetic flow control valve (model LDG-MIK, measurement accuracy ±0.5%), which adjust the flow of the second type of heat exchange medium (thermal oil) according to PLC instructions. The medium control module uses the above hardware to dynamically control the dual-circuit heat exchange medium based on the difference between the initial temperature and the target temperature, matching the functional limitations of the medium control module.

[0037] When gradient-adjusting the contact area ratio of the first-type heat exchange medium in different temperature zones based on the real-time temperature distribution of the high-temperature lime in the primary cooling circuit to obtain the segmented flow rate control coefficient, the spiral contact channel of the primary cooling circuit must first be segmented. This segmentation is based on the temperature distribution within the channel and is typically divided into high-temperature, medium-temperature, and low-temperature zones. The temperature ranges of these three zones are determined based on the actual requirements of the lime cooling process and the temperature variation within the spiral contact channel. For example, the high-temperature zone can be defined as a region with a temperature above a certain threshold, the medium-temperature zone as a region between two thresholds, and the low-temperature zone as a region below the other threshold.

[0038] After completing the zone division, the mass percentage of high-temperature lime within each temperature zone needs to be calculated to obtain mass distribution data for each temperature zone. This is accomplished by installing mass sensors at the entrance, midpoint, and exit of the spiral contact channel of the main cooling circuit. These mass sensors must meet the measurement requirements of the industrial site, possessing high accuracy and stability, and be able to accurately and in real time collect lime mass data at each location. The mass sensor installation locations must be strategically designed to ensure that the collected data accurately reflects the lime quality within the corresponding zone.

[0039] After the quality sensor collects lime mass data at the inlet, midpoint, and outlet in real time, further calculations and processing are performed. The mass data difference between the inlet and midpoint values ​​can be used to calculate the lime mass in the high-temperature section. Specifically, the mass data at the inlet represents the total mass of lime entering the spiral contact channel, while the mass data at the midpoint represents the mass of lime remaining after passing through the high-temperature section. The difference between the two represents the mass of lime processed in the high-temperature section. Similarly, the mass data difference between the midpoint and outlet values ​​can be used to calculate the lime mass in the medium-temperature section. The mass data at the outlet minus the mass data at the midpoint gives the mass of lime processed in the medium-temperature section. The mass data at the outlet directly corresponds to the lime mass in the low-temperature section because, after processing in the high-temperature and medium-temperature sections, the remaining lime completes its final cooling process in the low-temperature section.

[0040] After obtaining the lime mass for each temperature range, we need to calculate the mass contribution of each temperature range. Divide the lime mass in the high-temperature range by the total lime mass to obtain the mass contribution data for the high-temperature range. Similarly, divide the lime mass in the medium-temperature range and the lime mass in the low-temperature range by the total mass to obtain the mass contribution data for the medium-temperature range and the low-temperature range, respectively. The total mass here refers to the lime mass data collected at the inlet, as the mass of the lime does not change during the cooling process; only the temperature decreases.

[0041] When calculating mass percentages, attention must be paid to data accuracy and real-time performance. Because lime continuously enters the main cooling circuit, mass sensors must continuously collect data, and the data processing system must calculate and update this data in real time to reflect the actual mass percentages within each temperature range. If a mass sensor malfunctions or an anomaly occurs during data collection, prompt repair and resolution are required to ensure the reliability of the statistical results.

[0042] By segmenting the spiral contact channel of the main cooling circuit and calculating the mass percentage of each temperature segment, we can understand the distribution of high-temperature lime in different temperature segments. This information is crucial for subsequently adjusting the contact area percentage of the first-type heat exchange medium in different temperature segments, because lime in different temperature segments requires different heat exchange intensities, and the size of the contact area directly affects the effectiveness of heat exchange. For example, in the high-temperature segment, the lime temperature is higher, requiring more heat exchange medium to absorb heat, so the contact area percentage of the heat exchange medium in this segment may need to be increased; in the low-temperature segment, the lime temperature is relatively low, the heat exchange demand is reduced, and the contact area percentage can be reduced accordingly.

[0043] Furthermore, the impact of the spiral contact channel's structural characteristics on lime mass distribution must be considered throughout the entire process. Parameters such as the spiral angle and pitch of the spiral channel affect the flow rate and distribution of lime within the channel, and thus the mass distribution within each temperature zone. Therefore, these factors must be comprehensively considered when designing the spiral contact channel to ensure the rationality of zone division and mass statistics. Furthermore, the installation and maintenance of mass sensors must comply with relevant specifications, and sensors must be regularly calibrated and inspected to ensure the accuracy of collected data.

[0044] Through the above steps, we have completed the statistical analysis of the mass distribution of high-temperature lime in different temperature zones within the main cooling circuit, providing the foundation for subsequent calculations of contact area adjustments and the sectionalized control coefficients for medium flow rates. The accuracy and reliability of this data directly impacts the control effectiveness and heat exchange efficiency of the entire cooling system. Therefore, in actual operation, it is crucial to strictly adhere to the prescribed procedures and methods to ensure accuracy at every step.

[0045] Example 3: When calculating the contact area adjustment for each temperature zone based on the mass distribution data for each temperature zone and the preset contact area baseline value for the corresponding zone to determine the contact area ratio of the first-type heat exchange medium in each temperature zone, it is necessary to obtain preset contact area baseline values ​​for the high-temperature zone, the medium-temperature zone, and the low-temperature zone. These baseline values ​​are determined based on historical data and engineering practice regarding heat exchange requirements in different temperature ranges during the lime cooling process. For example, the high-temperature zone has a relatively large preset contact area baseline value due to its high heat exchange demand. Different baseline values ​​are set for the medium-temperature zone and the low-temperature zone based on the law of decreasing heat load.

[0046] After obtaining the mass ratio data of each temperature segment (the data is obtained from the ratio of the lime mass to the total mass in each temperature segment in Example 2), the mass ratio data of each temperature segment is multiplied by the preset contact area reference value of the corresponding segment to obtain the contact area adjustment amount of each temperature segment. Specifically, assuming that the mass ratio of the high temperature segment is , the preset contact area reference value is , then the contact area adjustment amount in the high temperature section is ; The mass proportion of the medium temperature section is The default contact area is , the adjustment amount is ; The mass proportion of the low temperature section is The default contact area is , the adjustment amount is The total contact area adjustment needs to be calculated, which is the sum of the contact area adjustments of the three sections. The expression is:

[0047] in, represents the total contact area adjustment, 、 、 are the mass proportions of the high temperature section, medium temperature section, and low temperature section, respectively. 、 、 are the preset contact area reference values ​​of the corresponding sections respectively.

[0048] Divide the contact area adjustment of each temperature section by the total contact area adjustment to obtain the contact area ratio of the first type of heat exchange medium in different temperature sections. For example, the contact area ratio of the high temperature section is , the medium temperature section is , the low temperature section is .

[0049] In practice, the preset contact area baseline value must take into account the structural parameters of the spiral contact channel. For example, factors such as the spiral channel's inner diameter, pitch, and spiral angle affect the actual contact area between the heat exchange medium and the lime, so the baseline value must match the channel's physical dimensions. Furthermore, the real-time performance of mass fraction data is crucial. Since lime flows continuously through the primary cooling circuit, the mass sensor must continuously collect data, and the data processing system must update the mass fraction of each temperature zone in real time to ensure that the calculated contact area adjustment reflects the actual state of the current lime distribution.

[0050] The calculation of the contact area adjustment also needs to consider the flow characteristics of the heat exchange medium. Factors such as the flow rate and turbulence of the first-class heat exchange medium within the spiral channel will affect the effective utilization of the contact area. Therefore, the preset contact area baseline value needs to be modified in conjunction with the medium's flow parameters. For example, when the medium flow rate is high, it may be necessary to increase the contact area adjustment to compensate for the shortened contact time caused by the fast flow rate to ensure heat exchange efficiency.

[0051] During data collection, the placement of temperature sensors must accurately reflect the temperature boundaries of each zone. The boundary temperatures between the high-temperature and medium-temperature zones, and between the medium-temperature and low-temperature zones, must be determined using real-time temperature monitoring data to ensure accurate zone division and, consequently, the reliability of mass fraction data. Misalignment of the temperature sensor's measurement position can lead to incorrect zone division, causing the calculated contact area adjustment to deviate from actual requirements and compromising heat exchange effectiveness.

[0052] The calculation of the total contact area adjustment must consider the system's heat load balance. If the initial temperature or mass flow rate of the lime changes, the mass fraction of each temperature zone will change accordingly, affecting the calculated contact area adjustment and fraction. At this point, the system must dynamically update the mass fraction data for each temperature zone based on the real-time collected initial temperature and mass flow parameters, and recalculate the contact area adjustment to adapt to the new heat exchange requirements.

[0053] When calculating the contact area percentage, the physical properties of the heat exchange medium must also be considered. Different types of first-class heat exchange media (such as gas or liquid) have different thermal conductivity coefficients and specific heat capacities. These parameters affect the heat exchange efficiency per unit contact area. Therefore, the preset contact area baseline value needs to be set differently based on the medium type. For example, when using gas as the heat exchange medium, due to its lower thermal conductivity coefficient, a larger contact area percentage may be required to achieve the same heat exchange effect.

[0054] The entire calculation process must be executed in real time by the control system's processor. The processor receives mass data from the mass sensor and temperature data from the temperature sensor, calls a preset database of contact area baseline values, and generates the contact area percentage for each temperature zone according to the aforementioned calculation logic. The results are then transmitted to the medium control module, providing a basis for subsequent flow rate control. During this process, the stability of data transmission and the accuracy of the calculations directly impact the system's control response speed, so it is crucial to ensure that the control system's hardware configuration and software algorithms meet the requirements of real-time calculations.

[0055] The database of preset contact area baseline values ​​requires regular updating and maintenance. Actual heat exchange requirements may change as the lime cooling process is optimized or equipment wears out. In these cases, the baseline values ​​must be revised based on actual production data to ensure the validity of the contact area adjustment calculations. For example, scaling on the inner wall of the spiral channel reduces the actual contact area. In this case, the preset contact area baseline value must be increased to compensate for the impact of scaling on heat exchange efficiency.

[0056] Through the above steps, the contact area ratio of the first type of heat exchange medium is dynamically adjusted according to the mass distribution of lime in different temperature sections, so that the distribution of the heat exchange medium can match the temperature distribution characteristics of the lime, thereby providing more contact area in the high-temperature section to enhance heat exchange, and reducing the contact area in the low-temperature section to avoid overcooling, ultimately achieving high efficiency and energy saving in the cooling process.

[0057] Example 4: When obtaining and summarizing the medium flow rate segmentation control coefficients based on the contact area ratios of each temperature segment and the flow rate correction coefficient table for the corresponding segment, it is necessary to retrieve the flow rate correction coefficients corresponding to the contact area ratios of the high-temperature segment, the medium-temperature segment, and the low-temperature segment from a preset flow rate correction coefficient table. This flow rate correction coefficient table is established through statistical analysis of a large amount of historical operating data and records the flow rate correction coefficients corresponding to different contact area ratios.

[0058] For example, suppose the previous calculations show that the contact area percentage for the high-temperature section is 40%, the medium-temperature section is 35%, and the low-temperature section is 25%. The operator then needs to look up the corresponding correction factor in the flow rate correction factor table based on these percentages. Assume that in the table, when the contact area percentage for the high-temperature section is 40%, the corresponding flow rate correction factor is 1.2; when the contact area percentage for the medium-temperature section is 35%, the corresponding correction factor is 0.9; and when the contact area percentage for the low-temperature section is 25%, the corresponding correction factor is 0.7.

[0059] Multiply the contact area percentage of each temperature range by the velocity correction factor for the corresponding range. For example, 40% of the contact area percentage in the high-temperature range is multiplied by the correction factor of 1.2 to get 0.48; 35% of the contact area percentage in the medium-temperature range is multiplied by 0.9 to get 0.315; and 25% of the contact area percentage in the low-temperature range is multiplied by 0.7 to get 0.175.

[0060] Then, the sum of these multiplication results is used to obtain the medium flow rate segmentation control coefficient. In this example, 0.48 + 0.315 + 0.175 = 0.97, which is the final medium flow rate segmentation control coefficient.

[0061] In practice, establishing a flow rate correction factor table requires consideration of multiple factors. The first is the properties of the lime. Different types and particle sizes of lime have different heat exchange requirements during the cooling process, so a flow rate correction factor table tailored to each lime type is necessary. For example, finer-particle lime may have a larger specific surface area, requiring a higher flow rate to ensure effective cooling during heat exchange. Therefore, the corresponding flow rate correction factor may vary.

[0062] The type of heat exchange medium also affects the flow rate correction factor table. If gas is used as the first type of heat exchange medium, due to its relatively low thermal conductivity, a higher flow rate may be required to compensate for this deficiency. Therefore, in the flow rate correction factor table, the corresponding correction factor for the same contact area ratio may be higher than when using a liquid medium.

[0063] The structural parameters of the spiral contact channels in the primary cooling circuit also need to be considered. Factors such as the channel's helical angle, pitch, and diameter affect the flow of the heat exchange medium within the channel, thus affecting heat exchange efficiency. Therefore, when creating the flow rate correction factor table, adjustments should be made based on the specific channel structural parameters.

[0064] When retrieving flow rate correction coefficients, it is important to ensure data accuracy and real-time availability. As the system operates, factors that may affect heat exchange efficiency, such as scaling within the channels and changes in the properties of the heat exchange medium, may arise. These factors require timely updating and maintenance of the flow rate correction coefficient table to ensure that the retrieved correction coefficients accurately reflect the current situation.

[0065] For example, when it is found that the heat exchange efficiency of the main cooling circuit has decreased, it may be due to scaling in the channel, which has reduced the actual contact area. At this time, it is necessary to check and adjust the flow rate correction coefficient table and appropriately increase the correction coefficient to increase the flow rate of the heat exchange medium and compensate for the loss of heat exchange efficiency caused by scaling.

[0066] In actual operation, the process of retrieving the flow rate correction coefficient and calculating the medium flow rate segment regulation coefficient is automatically completed by the control system of the system. The control system will collect the contact area proportion data of each temperature segment in real time, then retrieve the corresponding correction coefficient from the preset flow rate correction coefficient table, calculate the medium flow rate segment regulation coefficient, and transmit the coefficient to the medium regulation module for correcting the initial flow rate of the first type of heat exchange medium.

[0067] To ensure that the control system can accurately retrieve the corresponding flow rate correction coefficient, the flow rate correction coefficient table needs to be stored and managed according to certain rules. For example, the contact area proportion can be divided into multiple intervals, and each interval corresponds to a correction coefficient, which can improve the efficiency and accuracy of retrieval. At the same time, the flow rate correction coefficient table needs to be backed up to prevent data loss.

[0068] During system operation, the operator can also manually adjust the flow rate correction coefficient table according to the actual situation. For example, when encountering special production conditions or when the properties of lime change significantly, the operator can manually input new correction coefficients through the human-machine interface of the control system to adapt to new production needs.

[0069] Through the above steps, the medium flow rate segment regulation coefficient can be dynamically adjusted according to the contact area proportion of each temperature segment, thereby realizing the segment regulation of the flow rate of the first type of heat exchange medium. This regulation method can make the flow rate of the heat exchange medium more match the heat exchange needs of lime in different temperature segments, providing higher flow rate in high temperature segments to strengthen heat exchange, and appropriately reducing the flow rate in low temperature segments to save energy, thereby improving the efficiency and economy of the entire cooling system.

[0070] Example 5: The determination of the cooling effect needs to rely on the data support provided by the parameter acquisition module and the process monitoring module. The parameter acquisition module includes a PT100 platinum resistance temperature sensor (measuring range 0-1000℃, accuracy ±0.2℃) and a vortex flowmeter (range 0-80t / h, accuracy ±1.0%) installed at the outlet of the lime kiln, which respectively collect the initial temperature parameters and mass flow parameters of the high-temperature lime; at the same time, it calls the preset database (industrial-grade storage server, which stores lime cooling process standards, including the target temperature of metallurgical lime ≤60℃, basic parameters of heat exchange media, etc.) to output the benchmark data required for judgment; the process monitoring module installs a K-type thermocouple temperature sensor (measuring range 0-800℃, accuracy ±0.5℃) in the high-temperature section (first 3 circles), medium-temperature section (middle 3 circles), and low-temperature section (last 2 circles) of the spiral contact channel of the main cooling circuit to collect the real-time temperature of the lime; a PT100 temperature sensor is installed at the connection between the main circuit and the auxiliary circuit to collect the outlet temperature of the first type of heat exchange medium; and a K-type thermocouple temperature sensor is installed at the inlet and outlet of the nested outer tube of the auxiliary circuit. A PT100 temperature sensor (measuring range 0-300°C, accuracy ±0.2°C) collects the inlet and outlet temperatures of the second-type heat exchange medium. All sensor data is transmitted to the control unit in real time via Advantech's ADAM-4017 data acquisition module (8-channel analog input).

[0071] When correcting the initial flow rate of the first type of heat exchange medium based on the medium flow rate segmented control coefficient to obtain the controlled flow rate of the main cooling circuit medium, the initial flow rate of the first type of heat exchange medium must be obtained. This initial flow rate is typically set based on the design requirements of the lime cooling process and stored in the system's parameter database. For example, under design conditions, the initial flow rate can be set to a fixed value, which is determined by combining parameters such as the initial lime temperature, mass flow rate, and target temperature.

[0072] The initial flow rate of the first type of heat exchange medium is multiplied by the medium flow rate segmentation control coefficient to obtain the corrected flow rate value. For example, if the initial flow rate is v0 and the medium flow rate segmentation control coefficient is k, the corrected flow rate is v0 × k. This calculation process is automatically performed by the system control system. The control system obtains the medium flow rate segmentation control coefficient from the data acquisition module and calls the initial flow rate parameters from the parameter database. The internal calculation unit completes the multiplication operation.

[0073] The rotational speed of the conveying device of the first heat exchange medium is adjusted by a flow control valve. The flow control valve is installed on the conveying pipeline of the heat exchange medium, and the opening degree of the flow control valve is associated with the rotational speed of the conveying device. The control system generates a control signal according to the corrected flow rate value, and transmits the control signal to an actuator of the flow control valve. The actuator adjusts the opening degree of the valve to change the rotational speed of the conveying device. For example, when the corrected flow rate needs to be increased, the control system sends a signal to increase the opening degree of the flow control valve, and the rotational speed of the conveying device is increased, so that the conveying amount of the heat exchange medium is increased. Conversely, when the flow rate needs to be reduced, the opening degree of the valve is reduced, and the rotational speed of the conveying device is reduced.

[0074] The conveying device is usually a pump or a fan, and the rotational speed of the conveying device is positively correlated with the flow rate. When adjusting the rotational speed, the performance parameters of the device, such as the rated rotational speed and the power, need to be considered to ensure that the adjusted rotational speed is within the safe operating range of the device. At the same time, the adjustment accuracy and response speed of the flow control valve need to meet the system requirements. For example, the minimum adjustment step of the valve should ensure the accuracy of the flow rate control, and the response time should match the dynamic changes of the system to avoid adjustment lag.

[0075] After the output of the flow rate of the main cooling loop medium is completed, the temperature data collected in real time and the preset heat balance relationship are combined to determine whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold. In the specific operation, the difference between the initial temperature of the high-temperature lime in the main cooling loop and the real-time temperature is calculated to obtain the lime temperature drop value. The initial temperature is the temperature parameter collected at the outlet of the lime kiln, and the real-time temperature is the data monitored by the temperature sensor arranged at the outlet of the main cooling loop. The difference between the two reflects the temperature reduction amplitude of the lime in the main cooling loop.

[0076] The difference between the outlet temperature and the inlet temperature of the first heat exchange medium is calculated to obtain the medium temperature rise value. The inlet temperature is the temperature of the first heat exchange medium when it enters the main cooling loop, and the outlet temperature is the temperature after the heat exchange with the high-temperature lime. The difference reflects how much heat the heat exchange medium absorbs from the lime.

[0077] The difference between the outlet temperature and the inlet temperature of the second heat exchange medium in the auxiliary recovery loop is calculated to obtain the recovery medium temperature rise value. The inlet temperature of the second heat exchange medium is the temperature when it enters the auxiliary recovery loop, and the outlet temperature is the temperature after the indirect heat conduction with the first heat exchange medium. The difference reflects the effect of waste heat recovery.

[0078] The effect determination module includes: ① Data processing unit: integrated in the Siemens S7-1200 PLC, with a built-in thermal balance determination algorithm, receives temperature data transmitted by the process monitoring module, calculates the lime temperature drop value, the first-type medium temperature rise value, and the second-type medium temperature rise value, and then obtains the primary heat exchange efficiency coefficient (lime temperature drop value / first-type medium temperature rise value) and the secondary heat recovery efficiency coefficient (first-type medium temperature rise value / second-type medium temperature rise value); ② Display and alarm unit: Using the Weiluntong TK6071IP industrial touch screen (7 inches, resolution 800×480), it displays two efficiency coefficients and preset thresholds in real time (primary efficiency coefficient 3.5-5.0, secondary efficiency coefficient 1.5-2.2); if both coefficients are within the threshold range, "Cooling qualified" is displayed; if any coefficient exceeds the threshold, "Cooling unqualified" is displayed and an audible and visual alarm is triggered.

[0079] The determination is made based on the ratio of the lime temperature drop, the medium temperature rise, and the recovered medium temperature rise, combined with a preset heat balance matching threshold. For example, the ratio of the lime temperature drop to the medium temperature rise is defined as the primary heat exchange efficiency coefficient, while the ratio of the medium temperature rise to the recovered medium temperature rise is defined as the secondary heat recovery efficiency coefficient. The preset heat balance matching threshold is set according to the lime cooling process standard. For example, the primary heat exchange efficiency coefficient must be within a certain range, and the secondary heat recovery efficiency coefficient must also meet the corresponding range requirements.

[0080] If both the primary heat exchange efficiency coefficient and the secondary heat recovery efficiency coefficient are within the preset thermal balance matching threshold range, the high-temperature lime is considered to meet the cooling standard corresponding to the target temperature threshold. If either coefficient exceeds the threshold range, it is considered not to meet the standard. For example, if the primary heat exchange efficiency coefficient is below the lower threshold, it may indicate that the heat exchange effect of the main cooling circuit is insufficient and the lime has not been cooled to the target temperature. If the secondary heat recovery efficiency coefficient is above the upper threshold, it may indicate that the heat transfer efficiency of the auxiliary recovery circuit is abnormal, and the system operation status needs to be checked.

[0081] Throughout the entire determination process, the accuracy of temperature data collection is crucial. Each temperature sensor requires regular calibration to ensure accurate measurement data. For example, temperature sensors at the inlet and outlet of the main cooling circuit and the auxiliary recovery circuit must be periodically calibrated according to metrological standards to avoid erroneous determination results due to sensor errors. Furthermore, the frequency of data collection must match the time constant of the lime cooling process to ensure that real-time temperature data can promptly reflect dynamic changes in the system.

[0082] The preset thermal balance matching threshold also needs to be adjusted based on actual production conditions. Changes in lime type, initial temperature, or mass flow rate will alter the thermal balance relationship, necessitating a reset of the threshold range. For example, when processing lime of varying particle sizes, their thermal conductivity characteristics may vary, potentially shifting the acceptable range for the primary heat exchange efficiency coefficient. In this case, a new threshold must be determined through process testing to ensure the reliability of the determination results.

[0083] Furthermore, the control system must include data storage and historical query capabilities, recording temperature data, efficiency coefficients, and results for each determination, enabling operators to analyze system operating trends. If cooling standards are repeatedly not met, the system can automatically trigger an alarm, prompting operators to check the operating status of the primary cooling circuit or auxiliary recovery circuit, such as insufficient heat exchange medium flow or pipe scaling.

[0084] Through the above steps, dynamic control of the flow rate of the medium in the main cooling circuit and real-time determination of the cooling effect are achieved, enabling the system to automatically adjust operating parameters according to the temperature changes and heat exchange requirements of the lime, ensuring that the high-temperature lime is continuously and stably cooled to the target temperature, while efficiently recovering waste heat and improving energy utilization efficiency.

[0085] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0086] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A continuous lime cooling method with double-circuit waste heat recovery, characterized in that: include: Obtain the initial temperature parameters and mass flow parameters of the high-temperature lime at the lime kiln outlet, and simultaneously extract the target temperature threshold and basic parameters of the heat exchange medium in the lime cooling process standard from the preset database; Construct a dual-circuit waste heat recovery path consisting of a main cooling circuit and an auxiliary recovery circuit, wherein the main cooling circuit is used to carry out the direct contact heat exchange process between the high-temperature lime and the first type of heat exchange medium, and the auxiliary recovery circuit is used to carry out the indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium; Based on the difference between the initial temperature parameter and the target temperature threshold, the flow rate of the first type of heat exchange medium in the main cooling loop and the flow rate of the second type of heat exchange medium in the auxiliary recovery loop are dynamically controlled; Real-time collection of high-temperature lime temperature data in the main cooling circuit and outlet temperature data of the first type of heat exchange medium, and simultaneous collection of inlet and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery circuit; Based on the real-time collected temperature data and the preset heat balance relationship, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold; Among them, the flow rate of the first type of heat exchange medium in the main cooling circuit is dynamically controlled, including: based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the contact area ratio of the first type of heat exchange medium in different temperature sections is gradiently adjusted to obtain the medium flow rate segmentation control coefficient; based on the medium flow rate segmentation control coefficient, the initial flow rate of the first type of heat exchange medium is corrected to obtain the main cooling circuit medium control flow rate.

2. A continuous lime cooling method with double-circuit waste heat recovery according to claim 1, characterized in that: Construct a dual-loop waste heat recovery path consisting of a primary cooling loop and an auxiliary recovery loop, including: The pipeline structure of the main cooling circuit is set as a spiral contact channel, and the pipeline structure of the auxiliary recovery circuit is set as a nested sleeve structure. The main cooling circuit outlet and the auxiliary recovery circuit inlet are sealed and connected through flange connection components to form a dual-circuit waste heat recovery path.

3. A continuous lime cooling method with double-circuit waste heat recovery according to claim 2, characterized in that: Based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the contact area ratio of the first type of heat exchange medium in different temperature sections is gradiently adjusted to obtain the medium flow rate segmentation control coefficient, including: The spiral contact channel of the main cooling circuit is divided into sections to obtain a high-temperature section, a medium-temperature section, and a low-temperature section; The mass proportion of high-temperature lime in the high-temperature section, the medium-temperature section, and the low-temperature section is calculated to obtain the mass distribution data of each temperature section; Calculating the contact area adjustment amount for each temperature section based on the mass distribution data of each temperature section and the preset contact area reference value of the corresponding section to obtain the contact area ratio of the first type of heat exchange medium in different temperature sections; Based on the contact area ratio of each temperature section and the flow rate correction coefficient table of the corresponding section, the medium flow rate segment control coefficient is retrieved and summarized.

4. A continuous lime cooling method with double-circuit waste heat recovery according to claim 3, characterized in that: The mass proportion of high-temperature lime in the high-temperature section, medium-temperature section and low-temperature section is calculated to obtain the mass distribution data of each temperature section, including: Quality sensors are installed at the entrance, middle point and exit of the spiral contact channel of the main cooling circuit to collect lime quality data at each location in real time through the quality sensors; The lime mass in the high temperature section is calculated based on the difference in mass data between the inlet and the midpoint, the lime mass in the medium temperature section is calculated based on the difference in mass data between the midpoint and the outlet, and the lime mass in the low temperature section is calculated based on the mass data at the outlet; The lime mass in each temperature section was divided by the total mass to obtain the mass percentage data of each temperature section.

5. A continuous lime cooling method with double-circuit waste heat recovery according to claim 4, characterized in that: According to the mass distribution data of each temperature section and the preset contact area reference value of the corresponding section, the contact area adjustment amount of each temperature section is calculated to obtain the contact area ratio of the first type of heat exchange medium in different temperature sections, including: Obtaining preset contact area reference values ​​for the high temperature section, the medium temperature section, and the low temperature section; Multiplying the mass ratio data of each temperature section by the preset contact area reference value of the corresponding section to obtain the contact area adjustment amount of each temperature section; The contact area adjustment amount of each temperature section is divided by the total contact area adjustment amount to obtain the contact area ratio of the first type of heat exchange medium in different temperature sections.

6. A continuous lime cooling method with double-circuit waste heat recovery according to claim 5, characterized in that: Based on the contact area ratio of each temperature section and the flow rate correction coefficient table of the corresponding section, the medium flow rate segment control coefficient is obtained and summarized, including: Look up the flow rate correction coefficients corresponding to the contact area ratios of the high-temperature section, the medium-temperature section, and the low-temperature section from the preset flow rate correction coefficient table; The contact area ratio of each temperature section is multiplied by the flow rate correction coefficient of the corresponding section and then summed to obtain the medium flow rate segment control coefficient.

7. A continuous lime cooling method with double-circuit waste heat recovery according to claim 6, characterized in that: The initial flow rate of the first type of heat exchange medium is corrected based on the medium flow rate segmented control coefficient to obtain the main cooling circuit medium control flow rate, including: The initial flow rate of the first type of heat exchange medium is multiplied by the medium flow rate segmentation control coefficient, and the speed of the conveying equipment of the first type of heat exchange medium is adjusted through the flow control valve to output the main cooling circuit medium control flow rate.

8. A continuous lime cooling method with double-circuit waste heat recovery according to claim 7, characterized in that: Based on the real-time collected temperature data and the preset heat balance relationship, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold, including: Calculate the difference between the initial temperature and the real-time temperature of the high-temperature lime in the main cooling circuit to obtain the lime temperature drop value, and calculate the difference between the outlet temperature and the inlet temperature of the first type of heat exchange medium to obtain the medium temperature rise value; Calculate the difference between the outlet temperature and the inlet temperature of the second type of heat exchange medium in the auxiliary recovery loop to obtain the temperature rise of the recovery medium; According to the proportional relationship between the lime temperature drop value, the medium temperature rise value and the recovered medium temperature rise value, combined with the preset thermal balance matching threshold, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold.

9. A continuous lime cooling method with double-circuit waste heat recovery according to claim 8, characterized in that: Based on the proportional relationship between the lime temperature drop, the medium temperature rise, and the recovered medium temperature rise, combined with the preset heat balance matching threshold, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold, including: The ratio of lime temperature drop to medium temperature rise is defined as the primary heat exchange efficiency coefficient, and the ratio of medium temperature rise to recovered medium temperature rise is defined as the secondary heat recovery efficiency coefficient. If the primary heat exchange efficiency coefficient and the secondary heat recovery efficiency coefficient are both within the preset thermal balance matching threshold range, it is determined that the high-temperature lime meets the cooling standard corresponding to the target temperature threshold, otherwise it is determined that it does not meet the cooling standard.

10. A continuous lime cooling system with double-circuit waste heat recovery, used to implement the continuous lime cooling method with double-circuit waste heat recovery according to any one of claims 1 to 9, characterized in that: include: The parameter acquisition module is used to obtain the initial temperature parameters and mass flow parameters of the high-temperature lime at the lime kiln outlet, and simultaneously extract the target temperature threshold and basic parameters of the heat exchange medium in the lime cooling process standard from the preset database; A circuit construction module is used to construct a dual-circuit waste heat recovery path including a main cooling circuit and an auxiliary recovery circuit, wherein the main cooling circuit is used to carry out a direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, and the auxiliary recovery circuit is used to carry out an indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium; a medium control module for dynamically controlling the flow rate of the first type of heat exchange medium in the main cooling loop and the flow rate of the second type of heat exchange medium in the auxiliary recovery loop based on the difference between the initial temperature parameter and the target temperature threshold; The process monitoring module is used to collect the real-time temperature data of the high-temperature lime in the main cooling loop and the outlet temperature data of the first type of heat exchange medium, and simultaneously collect the inlet and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery loop; The effect determination module is used to determine whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold based on the real-time collected temperature data and the preset heat balance relationship.

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