A continuous lime cooling method and system with dual-loop waste heat recovery

Abstract

This invention relates to the field of lime cooling technology and discloses a continuous lime cooling method and system with dual-loop waste heat recovery. The method acquires the initial temperature and mass flow rate parameters of the high-temperature lime at the lime kiln outlet, and simultaneously extracts the target temperature threshold and basic parameters of the heat exchange medium from a preset database of cooling process standards. Then, a dual-loop waste heat recovery path is constructed, including a main cooling loop and an auxiliary recovery loop. Based on the difference between the initial temperature and the target temperature, the flow rate of the first type of medium in the main loop and the flow rate of the second type of medium in the auxiliary loop are dynamically adjusted. Simultaneously, real-time data are collected on the real-time temperature of the high-temperature lime in the main loop, the outlet temperature of the first type of medium, and the inlet and outlet temperatures of the second type of medium in the auxiliary loop. Finally, based on the collected temperature data and a preset heat balance relationship, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature. This method achieves efficient cooling and waste heat recovery.

Description

Technical Field

[0001] This invention relates to the field of lime cooling technology, specifically to a continuous lime cooling method and system with dual-loop waste heat recovery. Background Technology

[0002] Lime, as an important industrial raw material, has wide applications in metallurgy, construction, chemical industry, and many other fields. During lime production, the high-temperature lime exiting the lime kiln typically requires cooling to meet the requirements of subsequent processing and use. However, traditional lime cooling technologies have several shortcomings. Most existing lime cooling methods employ single-loop cooling systems. In such systems, the heat exchange efficiency between the high-temperature lime and the heat exchange medium is low, resulting in a significant amount of waste heat that cannot be effectively recovered and utilized, leading to energy waste.

[0003] Single-loop systems struggle to precisely control the flow rate and velocity of the heat exchange medium based on temperature changes in the high-temperature lime, resulting in uneven cooling and impacting the cooling quality of the lime. Furthermore, the inadequate pipe structure design of traditional cooling systems limits the contact area between the heat exchange medium and the high-temperature lime, further reducing heat exchange efficiency. Moreover, existing cooling systems lack real-time temperature data acquisition and accurate assessment of heat balance during the cooling process, making it impossible to promptly understand the cooling effect and ensure that the high-temperature lime reaches the cooling standard corresponding to the target temperature threshold.

[0004] With the increasing demands for energy conservation and product quality in industrial production, traditional lime cooling technology can no longer meet the needs of actual production. There is an urgent need for a new lime cooling method and system that can improve waste heat recovery efficiency, achieve precise cooling, and ensure cooling quality. Summary of the Invention

[0005] The purpose of this invention is to provide a continuous lime cooling method and system with dual-loop waste heat recovery to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides a continuous lime cooling method with dual-loop waste heat recovery, the method comprising:

[0007] The initial temperature and mass flow rate parameters of the high-temperature lime at the outlet of the lime kiln are obtained, and the target temperature threshold and basic parameters of the heat exchange medium in the lime cooling process standard are extracted from the preset database simultaneously.

[0008] A dual-loop waste heat recovery path is constructed, comprising a main cooling loop and an auxiliary recovery loop. The main cooling loop is used to carry the direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery loop is used to carry the indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium.

[0009] 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.

[0010] Real-time temperature data of high-temperature lime in the main cooling circuit and outlet temperature data of the first type of heat exchange medium 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 circuit are collected simultaneously.

[0011] 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.

[0012] The dynamic control of the flow rate of the first type of heat exchange medium in the main cooling circuit includes: based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the proportion of the contact area of ​​the first type of heat exchange medium in different temperature ranges is adjusted in a gradient manner to obtain the segmented control coefficient of the medium flow rate; and the initial flow rate of the first type of heat exchange medium is corrected based on the segmented control coefficient of the medium flow rate to obtain the controlled flow rate of the medium in the main cooling circuit.

[0013] Preferably, a dual-loop waste heat recovery path is constructed, comprising a main cooling loop and an auxiliary recovery loop, including:

[0014] The main cooling circuit's piping structure is set as a spiral contact channel, and the auxiliary recovery circuit's piping structure is set as a nested sleeve structure. The outlet of the main cooling circuit and the inlet of the auxiliary recovery circuit are sealed and connected by flange connection components to form a dual-loop waste heat recovery path.

[0015] 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 ranges is adjusted in a gradient manner to obtain the segmented control coefficient of the medium flow rate, including:

[0016] The spiral contact channel of the main cooling circuit is divided into sections to obtain high-temperature section, medium-temperature section and low-temperature section;

[0017] The mass percentage of high-temperature lime in the high-temperature, medium-temperature, and low-temperature zones was statistically analyzed to obtain mass distribution data for each temperature zone.

[0018] Based on the mass distribution data of each temperature zone and the preset contact area benchmark value of the corresponding zone, the contact area adjustment amount of each temperature zone is calculated to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones.

[0019] Based on the contact area ratio of each temperature zone and the corresponding flow rate correction coefficient table, the medium flow rate segment control coefficient is obtained by looking up and summarizing.

[0020] Preferably, the mass percentage of high-temperature lime in the high-temperature, medium-temperature, and low-temperature zones is statistically analyzed to obtain mass distribution data for each temperature zone, including:

[0021] Mass sensors are installed at the inlet, midpoint, and outlet of the spiral contact channel in the main cooling circuit to collect lime quality data at each location in real time.

[0022] 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 location.

[0023] Divide the mass of lime in each temperature zone by the total mass to obtain the mass percentage data for each temperature zone.

[0024] Preferably, based on the mass distribution data of each temperature zone and the preset contact area benchmark value of the corresponding zone, the contact area adjustment amount of each temperature zone is calculated to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones, including:

[0025] Obtain the preset contact area reference values ​​for the high temperature section, medium temperature section, and low temperature section;

[0026] The mass percentage data of each temperature zone is multiplied by the preset contact area benchmark value of the corresponding zone to obtain the contact area adjustment amount of each temperature zone.

[0027] Divide the contact area adjustment amount in each temperature zone by the total contact area adjustment amount to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones.

[0028] Preferably, based on the contact area ratio of each temperature zone and the corresponding flow rate correction coefficient table, the medium flow rate segment control coefficient is obtained by looking up and summarizing, including:

[0029] Look up the flow rate correction coefficients corresponding to the contact area ratios of the high-temperature, medium-temperature, and low-temperature sections from the preset flow rate correction coefficient table;

[0030] The contact area ratio of each temperature zone is multiplied by the flow rate correction coefficient of the corresponding zone and then summed to obtain the segmented control coefficient of the medium flow rate.

[0031] Preferably, the initial flow rate of the first type of heat exchange medium is corrected based on the segmented control coefficient of the medium flow rate to obtain the controlled flow rate of the main cooling circuit medium, including:

[0032] The initial flow rate of the first type of heat exchange medium is multiplied by the segmented flow rate control coefficient of the medium, 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 controlled flow rate of the medium in the main cooling circuit.

[0033] Preferably, 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:

[0034] 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. 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.

[0035] 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 value of the recovery medium;

[0036] Based on the proportional relationship between the temperature drop of lime, the temperature rise of the medium, and the temperature rise of the recovery medium, and in conjunction 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.

[0037] Preferably, based on the proportional relationship between the lime temperature drop, the medium temperature rise, and the recovery medium temperature rise, and in conjunction with a preset heat balance matching threshold, it is determined whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold, including:

[0038] 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.

[0039] If both the primary heat exchange efficiency coefficient and the secondary heat recovery efficiency coefficient are within the preset heat balance matching threshold range, then the high-temperature lime is determined to meet the cooling standard corresponding to the target temperature threshold; otherwise, it is determined not to meet the standard.

[0040] Preferably, the present invention further includes a dual-loop waste heat recovery continuous lime cooling system for implementing the above-described dual-loop waste heat recovery continuous lime cooling method, the system comprising:

[0041] The parameter acquisition module is used to acquire the initial temperature parameters and mass flow rate 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 from the preset database in the lime cooling process standard.

[0042] The loop construction module is used to construct a dual-loop waste heat recovery path that includes a main cooling loop and an auxiliary recovery loop. The main cooling loop is used to carry the direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery loop is used to carry the indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium.

[0043] The medium control module is used to dynamically control 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 based on the difference between the initial temperature parameter and the target temperature threshold.

[0044] The process monitoring module is used to collect real-time temperature data of high-temperature lime in the main cooling circuit and outlet temperature data of the first type of heat exchange medium, and simultaneously collect inlet temperature data and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery circuit.

[0045] The effect judgment 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.

[0046] Compared with the prior art, the beneficial effects of the present invention are:

[0047] By constructing a dual-loop waste heat recovery path comprising a main cooling loop and an auxiliary recovery loop, the main cooling loop facilitates direct heat exchange between the high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery loop enables indirect heat conduction between the first and second types of heat exchange mediums. This dual-loop design significantly improves the efficiency of waste heat recovery, allowing more heat to be reused and reducing energy consumption. Based on the difference between the initial temperature parameters 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. 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 uniformly cooled to the target temperature.

[0048] The main cooling circuit's piping structure is designed as a spiral contact channel, while the auxiliary recovery circuit uses a nested sleeve structure, sealed together by flange 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 improving its effectiveness. When dynamically controlling 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 zones is adjusted in a gradient manner to obtain a segmented flow rate control coefficient. The initial flow rate is then corrected. This segmented control method can more accurately adapt to the cooling needs of different temperature zones, improving the accuracy and effectiveness of cooling.

[0049] The system collects temperature data in real time from the main cooling loop and auxiliary recovery loop. Based on a preset heat balance relationship, it determines whether the high-temperature lime meets the cooling standard. By calculating the ratio of lime temperature drop, medium temperature rise, and recovery medium temperature rise, and combining this with a heat balance matching threshold, the system can accurately understand the cooling effect and ensure that the high-temperature lime meets the cooling standard. The system includes a parameter acquisition module, a loop construction module, a medium control module, a process monitoring module, and an effect judgment module. These modules work together to automate and intelligently manage the lime cooling process, improving production efficiency and reducing labor costs. Attached Figure Description

[0050] Figure 1 This is a schematic diagram illustrating the working principle of the continuous lime cooling method with dual-loop waste heat recovery as described in this invention.

[0051] Figure 2 A flowchart illustrating the dual-loop waste heat recovery pathway;

[0052] Figure 3 A flowchart for calculating the segmented control coefficient of medium flow velocity;

[0053] Figure 4 This is a flowchart for obtaining mass distribution data for temperature zones. Detailed Implementation

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] Please see Figures 1-4 This invention provides a continuous lime cooling method with dual-loop waste heat recovery, the specific implementation steps of which are as follows:

[0056] The system acquires the initial temperature and mass flow rate parameters of the high-temperature lime at the lime kiln outlet, and simultaneously extracts the target temperature threshold and basic parameters of the heat exchange medium from a pre-set database of lime cooling process standards. The initial temperature parameters are acquired in real-time by a temperature sensor installed at the lime kiln outlet, while the mass flow rate parameters are obtained by a flow meter installed on the outlet pipeline. The pre-set database stores cooling process standards for different specifications of lime.

[0057] A dual-loop waste heat recovery path is constructed, comprising a main cooling loop and an auxiliary recovery loop. The main cooling loop is used to handle the direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery loop is used to handle the indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium.

[0058] 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 regulated. Specifically, the control system calculates the regulation parameters based on the difference, and then controls the speed of the flow control valve and the conveying equipment.

[0059] The system collects 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, while simultaneously collecting inlet and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery loop. Each temperature data point is collected by its corresponding temperature sensor and transmitted to the control system.

[0060] Based on real-time temperature data and a preset heat balance relationship, the system determines whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold. The control system calculates the relevant temperature difference and proportional relationship, compares it with the preset threshold, and then arrives at the determination result.

[0061] The dynamic control of the flow rate of the first type of heat exchange medium in the main cooling circuit includes: based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the proportion of the contact area of ​​the first type of heat exchange medium in different temperature ranges is adjusted in a gradient manner to obtain the segmented control coefficient of the medium flow rate; and the initial flow rate of the first type of heat exchange medium is corrected based on the segmented control coefficient of the medium flow rate to obtain the controlled flow rate of the medium in the main cooling circuit.

[0062] Example 1: In constructing the dual-loop waste heat recovery path, the main cooling loop's piping structure is designed as a spiral contact channel. The specific construction of this spiral contact channel must meet the actual requirements of the heat exchange process. For example, parameters such as the spiral angle, pitch, and channel diameter must be designed based on the heat exchange efficiency requirements between high-temperature lime and the first type of heat exchange medium. The spiral structure design effectively increases the flow path length of the high-temperature lime within the channel, thereby extending the contact time between the high-temperature lime and the first type of heat exchange medium. Simultaneously, 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.

[0063] The auxiliary recovery loop's piping structure is designed as a nested sleeve structure. This structure consists of an inner pipe and an outer pipe. The inner pipe transports the first type of heat exchange medium flowing from the main cooling loop, while the outer pipe transports the second type of heat exchange medium. The materials selected for the inner and outer pipes must consider factors such as thermal conductivity and corrosion resistance to ensure efficient heat transfer during the heat exchange process and to guarantee the pipeline's service life. The nested sleeve structure design allows the first and second types of heat exchange media to conduct heat indirectly without direct contact, avoiding potential problems caused by mixing the two media.

[0064] The main cooling circuit outlet and the auxiliary recovery circuit inlet are sealed together via flange connections. The selection of these flange connections must comply with relevant industry standards to ensure reliable sealing performance. During flange installation, strict adherence to installation specifications is required, including cleaning the flange surfaces, using appropriate gaskets, and evenly tightening the bolts to ensure a tight seal and prevent leakage of the heat exchange medium during flow. This sealed connection design allows the main cooling circuit and auxiliary recovery circuit to form a complete dual-loop waste heat recovery path, ensuring the continuity and stability of the heat exchange process.

[0065] In the main cooling circuit, high-temperature lime undergoes direct heat exchange with the first type of heat exchange medium. The selection of the first type of heat exchange medium must consider factors such as its heat capacity, boiling point, and chemical stability to ensure effective absorption of the heat from the high-temperature lime. When the high-temperature lime enters the spiral contact channel, it mixes and contacts thoroughly with the first type of heat exchange medium within the channel. Heat is transferred from the high-temperature lime to the first type of heat exchange medium, causing the temperature of the lime to decrease while the temperature of the first type of heat exchange medium increases.

[0066] In the auxiliary recovery loop, the first type of heat exchange medium, after its temperature rises, enters the inner tube of the nested tube structure and undergoes indirect heat transfer 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 transfer performance and safety. Heat is transferred from the first type of heat exchange medium to the second type of heat exchange medium through the inner tube wall, causing the temperature of the second type of heat exchange medium to rise, while the temperature of the first type of heat exchange medium further decreases. After heat transfer through the auxiliary recovery loop, the first type of heat exchange medium can re-enter the main cooling loop for reuse, improving the utilization rate of the heat exchange medium.

[0067] The construction of the entire dual-loop waste heat recovery path requires consideration of the compatibility and coordination of its various components. For example, the dimensions of the spiral contact channel in the main cooling loop and the nested sleeve structure in the auxiliary recovery loop need to be designed based on parameters such as the lime processing capacity, initial temperature, and target temperature to ensure that the entire system can efficiently complete the cooling and waste heat recovery tasks. Simultaneously, the pipeline layout must also consider spatial arrangement and ease of installation and maintenance, such as reserving sufficient space for the inspection and replacement of pipelines and equipment.

[0068] In addition, corresponding monitoring devices, such as temperature sensors and flow sensors, are required in the dual-loop waste heat recovery path to monitor the temperature and flow data of each part in real time. The installation locations of these monitoring devices must accurately reflect the actual situation during the heat exchange process, providing a reliable basis for subsequent medium control and effect assessment. Temperature sensors can be installed at the inlet, middle, and outlet positions of the main cooling loop, as well as the inlet and outlet positions of the auxiliary recovery loop, to collect real-time temperature data of the high-temperature lime and the heat exchange medium. Flow sensors can be installed on the pipelines transporting the heat exchange medium to monitor the flow rates of the first and second types of heat exchange media.

[0069] During system operation, real-time monitoring and management of each link in the dual-loop waste heat recovery path are required. For example, if the heat exchange effect in the main cooling loop is found to be poor, it may be necessary to adjust 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 loop decreases, it may be necessary to check the sealing performance of the nested sleeve structure or the performance of the second type of heat exchange medium.

[0070] The construction of the dual-loop waste heat recovery path is achieved through the hardware components of the loop construction module, which specifically includes: ① Main cooling loop component: namely the aforementioned spiral contact channel (material: 304 stainless steel, inner diameter: 200mm, pitch: 500mm, inner wall of the channel is coated with aluminum oxide wear-resistant coating), its function is to carry the direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium (air); ② Auxiliary recovery loop component: namely the aforementioned nested sleeve structure (inner tube is seamless steel pipe, inner diameter: 150mm; outer tube is stainless steel pipe, inner diameter: 250mm, gap between inner and outer tube is filled with aluminum silicate insulation cotton), its function is to carry the indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium (heat transfer oil); ③ Connecting component: namely the aforementioned flange connection component (model PN1.6MPa, material: 304 stainless steel, sealing gasket is graphite composite gasket), which achieves a sealed connection between the main cooling loop outlet and the auxiliary recovery loop inlet by bolt tightening, ensuring no leakage of the dual-loop medium. The aforementioned components work together to form a dual-loop waste heat recovery path, providing a hardware foundation for subsequent cooling and waste heat recovery.

[0071] Example 2: The flow rate regulation process of the first type of heat exchange medium relies on a medium regulation module, which includes: ① Control unit: using a Siemens S7-1200 PLC (equipped with analog input / output modules), with a built-in "medium flow rate segmented regulation coefficient calculation algorithm" to receive temperature data and output regulation commands; ② Main circuit execution components: including a variable frequency blower (air volume adjustment range 0-10000m³ / h, power 15kW) and an electric flow control valve (model ZDLP-16C, adjustment accuracy ±1%), which regulates the flow rate of the first type of heat exchange medium (air) according to PLC commands; ③ Auxiliary circuit execution components: including a gear pump (flow rate adjustment range 0-50m³ / h, power 7.5kW) and an electromagnetic flow control valve (model LDG-MIK, measurement accuracy ±0.5%), which regulates the flow rate of the second type of heat exchange medium (heat transfer oil) according to PLC commands. The medium control module, through the aforementioned hardware, dynamically controls the dual-loop heat exchange medium based on the difference between the initial temperature and the target temperature, thus matching the functional limitations of the medium control module.

[0072] When adjusting the contact area ratio of the first type of heat exchange medium in different temperature zones based on the real-time temperature distribution characteristics of high-temperature lime in the main cooling loop to obtain the segmented control coefficient of the medium flow rate, the spiral contact channel of the main cooling loop must first be segmented. The segmentation is based on the temperature distribution within the channel, typically divided into high-temperature, medium-temperature, and low-temperature zones. The temperature range division of these three zones needs to be determined in conjunction with the actual requirements of the lime cooling process and the temperature variation law within the spiral contact channel. For example, the high-temperature zone can be set as the area with a temperature above a certain threshold, the medium-temperature zone as the area between two thresholds, and the low-temperature zone as the area below another threshold.

[0073] After dividing the temperature zones, it is necessary to calculate the mass percentage of high-temperature lime within each zone to obtain mass distribution data for each zone. Specifically, mass sensors are installed at the inlet, midpoint, and outlet of the spiral contact channel in the main cooling circuit. These mass sensors must meet the measurement requirements of the industrial site, possessing high accuracy and stability, and capable of collecting lime mass data at each location in real time and accurately. The installation locations of the mass sensors must be rationally designed to ensure that the collected data accurately reflects the lime mass within the corresponding zone.

[0074] After real-time collection of lime mass data at the inlet, midpoint, and outlet positions using mass sensors, further calculations are performed. The mass of lime in the high-temperature section can be calculated based on the difference between the mass data at the inlet and midpoint. 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 remaining mass of lime after passing through the high-temperature section. The difference between the two is the mass of lime processed in the high-temperature section. Similarly, the mass of lime in the medium-temperature section can be calculated based on the difference between the mass data at the midpoint and the outlet. Subtracting the mass data at the outlet from 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 mass of lime in the low-temperature section, because after processing in the high-temperature and medium-temperature sections, the remaining lime undergoes its final cooling process in the low-temperature section.

[0075] After obtaining the mass of lime in each temperature range, it is necessary to calculate the mass percentage of each temperature range. Dividing the mass of lime in the high-temperature range by the total mass of lime yields the mass percentage for the high-temperature range. Similarly, dividing the mass of lime in the medium-temperature range and the low-temperature range by the total mass yields the mass percentages for the medium-temperature and low-temperature ranges, respectively. The total mass here refers to the mass of lime collected at the inlet, as the mass of the lime does not change during the cooling process; only the temperature decreases.

[0076] When calculating the mass percentage, it is crucial to ensure the accuracy and real-time nature of the data. Since lime continuously enters the main cooling circuit, the mass sensor needs to continuously collect data, and the data processing system must calculate and update the collected data in real time to reflect the actual mass percentage of lime in each temperature range. If the mass sensor malfunctions or anomalies occur during data acquisition, timely repair and handling are necessary to ensure the reliability of the statistical results.

[0077] By dividing the spiral contact channel of the main cooling circuit into sections and statistically analyzing the mass proportion of each temperature section, the distribution of high-temperature lime in different temperature zones can be understood. This information is crucial for subsequently adjusting the contact area proportion of the first-type heat exchange medium in different temperature zones, because lime in different temperature zones requires different heat exchange intensities, and the size of the contact area directly affects the heat exchange effect. For example, in the high-temperature zone, the lime temperature is high, requiring more heat exchange medium to absorb heat, so it may be necessary to increase the contact area proportion of the heat exchange medium in this zone; while in the low-temperature zone, the lime temperature is relatively low, the heat exchange demand is reduced, and the contact area proportion can be reduced accordingly.

[0078] Furthermore, the impact of the spiral contact channel's structural characteristics on lime mass distribution must be considered throughout the process. Parameters such as the spiral angle and pitch of the spiral channel affect the flow velocity and distribution of lime within the channel, thus influencing the mass proportion of 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. Simultaneously, the installation and maintenance of the mass sensors must be carried out according to relevant specifications, with regular calibration and inspection to ensure the accuracy of the collected data.

[0079] Through the above steps, the statistical data on the mass distribution of high-temperature lime in different temperature ranges of the main cooling circuit was completed. This provides the basic data for subsequent calculations of contact area adjustment and the determination of the segmented control coefficient of medium flow rate. The accuracy and reliability of this data directly affect the control effect and heat exchange efficiency of the entire cooling system. Therefore, in actual operation, it is necessary to strictly follow the prescribed procedures and methods to ensure that every step is accurate.

[0080] Example 3: When calculating the contact area adjustment amount for each temperature zone based on the mass distribution data of each temperature zone and the preset contact area benchmark value of the corresponding zone to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones, it is necessary to obtain the preset contact area benchmark values ​​for the high-temperature zone, the medium-temperature zone, and the low-temperature zone. These benchmark values ​​are determined based on historical data and engineering practice of heat exchange requirements in different temperature ranges in the lime cooling process. For example, the preset contact area benchmark value is relatively large in the high-temperature zone due to its high heat exchange requirements, while the medium-temperature zone and the low-temperature zone are set with different benchmark values ​​according to the heat load reduction law.

[0081] After obtaining the mass percentage data for each temperature zone (this data is derived from the ratio of lime mass to total mass in each temperature zone in Example 2), the mass percentage data for each temperature zone is multiplied by the preset contact area benchmark value for the corresponding zone to obtain the contact area adjustment amount for each temperature zone. Specifically, assuming the mass percentage of the high-temperature zone is... Its preset contact area benchmark value is The adjustment amount of the contact area in the high-temperature section is: The mass percentage of the medium-temperature zone is: The preset contact area benchmark value is The adjustment amount is The mass percentage of the low-temperature section is: The preset contact area benchmark value is The adjustment amount is The total contact area adjustment needs to be calculated, which is the sum of the contact area adjustments for the three sections. The expression is:

[0082]

[0083] in, This indicates the total contact area adjustment. , , These represent the mass percentages of the high-temperature, medium-temperature, and low-temperature zones, respectively. , , These are the preset contact area benchmark values ​​for the corresponding sections.

[0084] Dividing the contact area adjustment amount for each temperature range by the total contact area adjustment amount yields the proportion of the contact area of ​​the first-type heat exchange medium in different temperature ranges. For example, the contact area proportion in the high-temperature range is... The medium temperature range is The low-temperature section is .

[0085] In practice, setting the preset contact area baseline value requires consideration of the structural parameters of the spiral contact channel. For example, factors such as the inner diameter, pitch, and spiral angle of the spiral channel will affect the actual contact area between the heat exchange medium and the lime. Therefore, the baseline value must match the physical dimensions of the channel. Simultaneously, the real-time nature of the mass percentage data is crucial. Since the lime continuously flows through the main cooling circuit, the mass sensor needs to continuously collect data, and the data processing system needs to update the mass percentage of each temperature range in real time to ensure that the calculation of the contact area adjustment reflects the actual state of the current lime distribution.

[0086] The calculation of the contact area adjustment also needs to consider the flow characteristics of the heat exchange medium. Factors such as the flow velocity and turbulence level of the first type of heat exchange medium within the spiral channel will affect the effective utilization of the contact area. Therefore, the determination of the preset contact area baseline value needs to be corrected in conjunction with the flow parameters of the medium. For example, when the medium flow velocity is high, it may be necessary to increase the contact area adjustment to compensate for the shortened contact time caused by the high flow velocity, in order to ensure heat exchange efficiency.

[0087] During data acquisition, the placement of temperature sensors must accurately reflect the temperature boundaries of each zone. The boundary temperatures between high-temperature and medium-temperature zones, and between medium-temperature and low-temperature zones, need to be determined using real-time temperature monitoring data to ensure the accuracy of zone division and, consequently, the reliability of the mass percentage data. If the temperature sensor's measurement position is off, it may lead to incorrect zone division, causing the calculated contact area adjustment to deviate from actual requirements and affecting heat exchange efficiency.

[0088] The calculation of the total contact area adjustment must take into account the system's heat load balance. When the initial temperature or mass flow rate of the lime changes, the mass proportion of each temperature zone will change accordingly, thus affecting the calculation results of the contact area adjustment and proportion. At this time, the system needs to dynamically update the mass proportion data of each temperature zone based on the real-time collected initial temperature parameters and mass flow rate parameters, and recalculate the contact area adjustment to adapt to the new heat exchange requirements.

[0089] When calculating the contact area ratio, the physical properties of the heat exchange medium must also be considered. Different types of Class I heat exchange media (such as gases or liquids) 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 according to the type of medium. For example, when using a gas as a heat exchange medium, due to its lower thermal conductivity, a larger contact area ratio may be required to achieve the same heat exchange effect.

[0090] The entire calculation process needs to 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 contact area reference value database, generates the contact area ratio for each temperature range according to the above calculation logic, and transmits the results to the medium control module to provide a basis for subsequent flow rate control. In this process, the stability of data transmission and the accuracy of calculation directly affect the system's control response speed; therefore, it is necessary to ensure that the hardware configuration and software algorithm of the control system meet the requirements of real-time calculation.

[0091] The database of preset contact area baseline values ​​needs to be updated and maintained regularly. As the lime cooling process is optimized or equipment wears down, actual heat exchange requirements may change. In such cases, the baseline values ​​need to be corrected based on production practice data to ensure the effectiveness of the contact area adjustment calculations. For example, when scaling occurs on the inner wall of the spiral channel, the actual contact area decreases. In this case, the preset contact area baseline value needs to be increased to compensate for the impact of scaling on heat exchange efficiency.

[0092] 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 ranges. This allows the distribution of the heat exchange medium to match the temperature distribution characteristics of lime, thereby providing more contact area in high-temperature ranges to enhance heat exchange and reducing contact area in low-temperature ranges to avoid overcooling, ultimately achieving high efficiency and energy saving in the cooling process.

[0093] Example 4: When obtaining the segmented flow rate control coefficients for each temperature zone by looking up and summarizing the contact area ratio and corresponding flow rate correction coefficient table, it is necessary to retrieve the flow rate correction coefficients corresponding to the contact area ratios of the high-temperature, medium-temperature, and low-temperature zones from a preset flow rate correction coefficient table. This flow rate correction coefficient table was established through statistical analysis of a large amount of historical operating data, and it records the flow rate correction coefficients corresponding to different contact area ratios.

[0094] For example, suppose the previous calculations show that the contact area ratio for the high-temperature zone is 40%, for the medium-temperature zone it's 35%, and for the low-temperature zone it's 25%. In this case, the operator needs to look up the corresponding correction factor in the flow rate correction factor table based on these percentages. For instance, in the table, when the high-temperature zone's contact area ratio is 40%, the corresponding flow rate correction factor is 1.2; when the medium-temperature zone's contact area ratio is 35%, the corresponding correction factor is 0.9; and when the low-temperature zone's contact area ratio is 25%, the corresponding correction factor is 0.7.

[0095] Multiply the contact area percentage of each temperature zone by the corresponding flow velocity correction factor. That is, multiply the contact area percentage of 40% in the high temperature zone by the correction factor of 1.2 to get 0.48; multiply the contact area percentage of 35% in the medium temperature zone by 0.9 to get 0.315; and multiply the contact area percentage of 25% in the low temperature zone by 0.7 to get 0.175.

[0096] Then, the results of these multiplications are summed to obtain the segmented control coefficient of the medium flow rate. In this example, 0.48 + 0.315 + 0.175 = 0.97, and this 0.97 is the final segmented control coefficient of the medium flow rate.

[0097] In practical applications, establishing a flow rate correction factor table requires consideration of multiple factors. Firstly, the properties of the lime must be taken into account. Different types and particle sizes of lime have varying heat exchange requirements during cooling, necessitating the creation of corresponding flow rate correction factor tables for different lime types. For instance, finer-grained lime may have a larger specific surface area, requiring a higher flow rate to ensure effective cooling during heat exchange; therefore, its corresponding flow rate correction factor may differ.

[0098] The type of heat exchange medium also affects the establishment of the flow rate correction factor table. If a gas is used as the first type of heat exchange medium, a higher flow rate may be needed to compensate for the relatively low heat transfer efficiency of the gas. Therefore, the correction factor corresponding to the same contact area ratio in the flow rate correction factor table may be higher than when using a liquid medium.

[0099] The structural parameters of the spiral contact channel in the main cooling circuit also need to be considered. Factors such as the spiral angle, pitch, and diameter of the channel affect the flow state of the heat exchange medium within the channel, thus affecting the heat exchange efficiency. Therefore, when establishing the flow rate correction coefficient table, appropriate adjustments need to be made based on the specific channel structural parameters.

[0100] When retrieving flow rate correction factors, it is essential to ensure the accuracy and real-time nature of the data. As the system operates, factors that may affect heat exchange efficiency may arise, such as scaling within the channels or changes in the properties of the heat exchange medium. These factors necessitate timely updates and maintenance of the flow rate correction factor table to ensure that the retrieved correction factors accurately reflect the current actual conditions.

[0101] For example, if the heat exchange efficiency of the main cooling circuit is found to have decreased, it may be due to scaling in the channel, which reduces the actual contact area. In this case, 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 make up for the loss of heat exchange efficiency caused by scaling.

[0102] In actual operation, the process of retrieving the flow rate correction coefficient and calculating the segmented control coefficient of the medium flow rate is automatically completed by the system's control system. The control system collects the contact area ratio data of each temperature segment in real time, then retrieves the corresponding correction coefficient from the preset flow rate correction coefficient table, calculates it to obtain the segmented control coefficient of the medium flow rate, and transmits the coefficient to the medium control module for correcting the initial flow rate of the first type of heat exchange medium.

[0103] To ensure the control system can accurately retrieve the corresponding flow rate correction coefficients, the flow rate correction coefficient table needs to be stored and managed according to certain rules. For example, the contact area percentage can be divided into multiple intervals, with each interval corresponding to a correction coefficient. This improves the efficiency and accuracy of retrieval. Simultaneously, the flow rate correction coefficient table also needs to be backed up to prevent data loss.

[0104] During system operation, operators can also manually adjust the flow rate correction coefficient table according to actual conditions. For example, when encountering special production conditions or significant changes in lime properties, operators can manually input new correction coefficients through the human-machine interface of the control system to adapt to new production needs.

[0105] Through the above steps, the obtained medium flow rate segmentation control coefficient can be dynamically adjusted according to the contact area ratio of each temperature segment, thereby achieving segmented control of the flow rate of the first type of heat exchange medium. This control method allows the flow rate of the heat exchange medium to better match the heat exchange requirements of lime in different temperature segments, providing a higher flow rate in the high-temperature segment to enhance heat exchange, and appropriately reducing the flow rate in the low-temperature segment to save energy, thereby improving the efficiency and economy of the entire cooling system.

[0106] Example 5: The determination of the cooling effect depends 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 (measurement range 0-1000℃, accuracy ±0.2℃) and a vortex flow meter (range 0-80t / h, accuracy ±1.0%) installed at the lime kiln outlet to collect the initial temperature and mass flow parameters of the high-temperature lime, respectively. Simultaneously, it calls a preset database (an industrial-grade storage server storing lime cooling process standards, including target temperature ≤60℃ for metallurgical lime, basic parameters of the heat exchange medium, etc.) to output the benchmark data required for judgment. The process monitoring module installs one K-type thermocouple temperature sensor (measurement range 0-800℃, accuracy ±0.5℃) in each of the high-temperature section (first 3 turns), medium-temperature section (middle 3 turns), and low-temperature section (last 2 turns) of the spiral contact channel in the main cooling loop to collect the real-time lime temperature; one PT100 temperature sensor is installed at the connection between the main loop and the auxiliary loop to collect the outlet temperature of the first type of heat exchange medium; and one PT100 temperature sensor is installed at the inlet and outlet of the nested outer tube of the auxiliary loop. One PT100 temperature sensor (measurement range 0-300℃, accuracy ±0.2℃) is used to collect the inlet and outlet temperatures of the second type of heat exchange medium; all sensor data are transmitted to the control unit in real time through the Advantech ADAM-4017 data acquisition module (8-channel analog input).

[0107] When correcting the initial flow rate of the first type of heat exchange medium based on the segmented control coefficient of the medium flow rate to obtain the controlled flow rate of the main cooling circuit medium, it is necessary to obtain the initial flow rate of the first type of heat exchange medium. This initial flow rate is usually set according to the design requirements of the lime cooling process and stored in the system's parameter database. For example, the initial flow rate under the design conditions can be set to a certain fixed value, which is determined by combining parameters such as the initial temperature, mass flow rate, and target temperature of the lime.

[0108] The corrected flow rate is obtained by multiplying the initial flow rate of the first type of heat exchange medium by the flow rate segmentation control coefficient. For example, if the initial flow rate is v0 and the flow rate segmentation control coefficient is k, then the corrected flow rate is v0 × k. This calculation process is automatically executed by the system's control system. The control system obtains the flow rate segmentation control coefficient from the data acquisition module and retrieves the initial flow rate parameter from the parameter database, performing the multiplication operation through the internal processing unit.

[0109] The rotational speed of the conveying equipment for the first type of heat exchange medium is regulated by a flow control valve. The flow control valve is installed on the conveying pipeline of the heat exchange medium, and its opening degree is related to the rotational speed of the conveying equipment. The control system generates a control signal based on the corrected flow rate value and transmits it to the actuator of the flow control valve. The actuator adjusts the valve opening to change the rotational speed of the conveying equipment. For example, when the corrected flow rate needs to be increased, the control system sends a signal to increase the opening of the flow control valve, thereby increasing the rotational speed of the conveying equipment and increasing the conveying capacity of the heat exchange medium; conversely, when the flow rate needs to be decreased, the valve opening decreases, and the rotational speed of the conveying equipment decreases.

[0110] Conveying equipment is typically a pump or fan, and its rotational speed is positively correlated with its flow rate. When adjusting the rotational speed, the equipment's performance parameters, such as rated speed and power, must be considered to ensure that the adjusted speed is within the equipment's safe operating range. Simultaneously, the adjustment accuracy and response speed of the flow control valve must meet system requirements. For example, the valve's minimum adjustment step should ensure accurate flow rate control, and the response time should match the system's dynamic changes to avoid adjustment lag.

[0111] After outputting the controlled flow rate of the medium in the main cooling circuit, it is necessary to combine the real-time collected temperature data with the preset heat balance relationship to determine whether the high-temperature lime meets the cooling standard corresponding to the target temperature threshold. In specific operation, the difference between the initial temperature and the real-time temperature of the high-temperature lime in the main cooling circuit is first calculated to obtain the lime temperature drop value. The initial temperature is the temperature parameter collected at the lime kiln outlet, and the real-time temperature is the data monitored in real time by the temperature sensor set at the outlet of the main cooling circuit. The difference between the two reflects the degree of temperature reduction of the lime in the main cooling circuit.

[0112] The temperature rise of the medium is obtained by calculating the difference between the outlet temperature and the inlet temperature of the first type of heat exchange medium. The inlet temperature is the temperature of the first type of heat exchange medium when it enters the main cooling circuit, and the outlet temperature is its temperature after heat exchange with the high-temperature lime. This difference reflects the amount of heat absorbed by the heat exchange medium from the lime.

[0113] The temperature rise of the recovered medium is obtained by calculating the difference between the outlet temperature and the inlet temperature of the second type of heat exchange medium in the auxiliary recovery loop. The inlet temperature of the second type of heat exchange medium is its temperature when it enters the auxiliary recovery loop, and the outlet temperature is its temperature after indirect heat conduction with the first type of heat exchange medium. This difference reflects the effectiveness of waste heat recovery.

[0114] The effect judgment module includes: ① Data processing unit: integrated into Siemens S7-1200 PLC, with a built-in heat balance judgment algorithm, receiving temperature data transmitted from the process monitoring module, calculating the lime temperature drop, the first type of medium temperature rise, and the second type of medium temperature rise, and then obtaining the primary heat exchange efficiency coefficient (lime temperature drop / first type of medium temperature rise) and the secondary heat recovery efficiency coefficient (first type of medium temperature rise / second type of medium temperature rise); ② Display and alarm unit: using Weintek TK6071IP industrial touch screen (7-inch, 800×480 resolution), displaying the 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 either coefficient exceeds the threshold, "cooling unqualified" is displayed and an audible and visual alarm is triggered.

[0115] The efficiency coefficient of heat recovery is determined based on the ratio of lime temperature drop, medium temperature rise, and recovered medium temperature rise, combined with a preset heat balance matching threshold. For example, 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. 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.

[0116] If both the primary heat exchange efficiency coefficient and the secondary heat recovery efficiency coefficient are within the preset heat balance matching threshold range, the high-temperature lime is determined to meet the cooling standard corresponding to the target temperature threshold. If either coefficient exceeds the threshold range, it is determined not to meet the standard. For example, if the primary heat exchange efficiency coefficient is lower than 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 higher than the upper threshold, it may mean that the heat transfer efficiency of the auxiliary recovery circuit is abnormal, and the system operating status needs to be checked.

[0117] Throughout the entire judgment process, the accuracy of temperature data acquisition is crucial. Each temperature sensor must be calibrated regularly to ensure the accuracy of the measured data. For example, the temperature sensors at the inlet and outlet of the main cooling circuit and the auxiliary recovery circuit must be periodically verified according to metrological standards to avoid erroneous judgment results due to sensor errors. Simultaneously, the frequency of data acquisition must match the time constant of the lime cooling process to ensure that real-time temperature data can promptly reflect the dynamic changes of the system.

[0118] The preset heat balance matching threshold also needs to be adjusted according to actual production conditions. When the type of lime, initial temperature, or mass flow rate changes, the heat balance relationship will change accordingly, and the threshold range needs to be reset. For example, when processing lime of different particle sizes, their thermal conductivity characteristics are different, which may cause the reasonable range of the primary heat exchange efficiency coefficient to change. In this case, a new threshold needs to be determined through process experiments to ensure the reliability of the judgment results.

[0119] In addition, the control system must have data storage and historical query functions, recording the temperature data, efficiency coefficient, and judgment results for each determination, facilitating operators' analysis of system operating trends. When multiple consecutive judgments result in failure to meet cooling standards, the system can automatically trigger an alarm mechanism, prompting operators to check the operating status of the main cooling circuit or auxiliary recovery circuit, such as whether there are problems like insufficient heat exchange medium flow or pipe scaling.

[0120] Through the above steps, dynamic control of the medium flow rate in the main cooling circuit and real-time determination of the cooling effect are achieved. This enables the system to automatically adjust operating parameters according to the temperature changes of the lime and the heat exchange requirements, 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.

[0121] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0122] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A continuous lime cooling method with dual-loop waste heat recovery, characterized in that, include: The initial temperature and mass flow rate parameters of the high-temperature lime at the outlet of the lime kiln are obtained, and the target temperature threshold and basic parameters of the heat exchange medium in the lime cooling process standard are extracted from the preset database simultaneously. A dual-loop waste heat recovery path is constructed, comprising a main cooling loop and an auxiliary recovery loop. The main cooling loop is used to carry the direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery loop is used to carry 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 circuit and the flow rate of the second type of heat exchange medium in the auxiliary recovery circuit are dynamically controlled. Real-time temperature data of high-temperature lime in the main cooling circuit and outlet temperature data of the first type of heat exchange medium 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 circuit are collected simultaneously. 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. The dynamic control of the flow rate of the first type of heat exchange medium in the main cooling circuit includes: based on the real-time temperature distribution characteristics of the high-temperature lime in the main cooling circuit, the proportion of the contact area of ​​the first type of heat exchange medium in different temperature ranges is adjusted in a gradient manner to obtain the segmented control coefficient of the medium flow rate; and the initial flow rate of the first type of heat exchange medium is corrected based on the segmented control coefficient of the medium flow rate to obtain the controlled flow rate of the medium in the main cooling circuit. A dual-loop waste heat recovery path is constructed, comprising a main cooling loop and an auxiliary recovery loop, including: The main cooling circuit's piping structure is set as a spiral contact channel, and the auxiliary recovery circuit's piping structure is set as a nested sleeve structure. The outlet of the main cooling circuit and the inlet of the auxiliary recovery circuit are sealed and connected by flange connection components to form a dual-loop waste heat recovery path.

2. The continuous lime cooling method with dual-loop waste heat recovery according to claim 1, characterized in that, Based on the real-time temperature distribution characteristics of high-temperature lime in the main cooling circuit, the contact area ratio of the first type of heat exchange medium in different temperature ranges is adjusted in a gradient manner to obtain the segmented control coefficient of the medium flow rate, including: The spiral contact channel of the main cooling circuit is divided into sections to obtain high-temperature section, medium-temperature section and low-temperature section; The mass percentage of high-temperature lime in the high-temperature, medium-temperature, and low-temperature zones was statistically analyzed to obtain mass distribution data for each temperature zone. Based on the mass distribution data of each temperature zone and the preset contact area benchmark value of the corresponding zone, the contact area adjustment amount of each temperature zone is calculated to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones. Based on the contact area ratio of each temperature zone and the corresponding flow rate correction coefficient table, the medium flow rate segment control coefficient is obtained by looking up and summarizing.

3. The continuous lime cooling method with dual-loop waste heat recovery according to claim 2, characterized in that, The mass percentage of high-temperature lime in the high-temperature, medium-temperature, and low-temperature zones was statistically analyzed to obtain mass distribution data for each temperature zone, including: Mass sensors are installed at the inlet, midpoint, and outlet of the spiral contact channel in the main cooling circuit to collect lime quality data at each location in real time. 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 location. Divide the mass of lime in each temperature zone by the total mass to obtain the mass percentage data for each temperature zone.

4. The continuous lime cooling method with dual-loop waste heat recovery according to claim 3, characterized in that, Based on the mass distribution data of each temperature zone and the preset contact area benchmark value of the corresponding zone, the contact area adjustment amount of each temperature zone is calculated to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones, including: Obtain the preset contact area reference values ​​for the high temperature section, medium temperature section, and low temperature section; The mass percentage data of each temperature zone is multiplied by the preset contact area benchmark value of the corresponding zone to obtain the contact area adjustment amount of each temperature zone. Divide the contact area adjustment amount in each temperature zone by the total contact area adjustment amount to obtain the contact area ratio of the first type of heat exchange medium in different temperature zones.

5. The continuous lime cooling method with dual-loop waste heat recovery according to claim 4, characterized in that, Based on the contact area ratio of each temperature zone and the corresponding flow velocity correction coefficient table, the medium flow velocity segment control coefficients are retrieved and summarized, including: Look up the flow rate correction coefficients corresponding to the contact area ratios of the high-temperature, medium-temperature, and low-temperature sections from the preset flow rate correction coefficient table; The contact area ratio of each temperature zone is multiplied by the flow rate correction coefficient of the corresponding zone and then summed to obtain the segmented control coefficient of the medium flow rate.

6. The continuous lime cooling method with dual-loop waste heat recovery according to claim 5, characterized in that, The initial flow rate of the first type of heat exchange medium is corrected based on the segmented control coefficient of the medium flow rate to obtain the controlled flow rate of the main cooling circuit medium, including: The initial flow rate of the first type of heat exchange medium is multiplied by the segmented flow rate control coefficient of the medium, 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 controlled flow rate of the medium in the main cooling circuit.

7. The continuous lime cooling method with dual-loop waste heat recovery according to claim 6, 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: 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. 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 value of the recovery medium; Based on the proportional relationship between the temperature drop of lime, the temperature rise of the medium, and the temperature rise of the recovery medium, and in conjunction 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.

8. The continuous lime cooling method with dual-loop waste heat recovery according to claim 7, characterized in that, Based on the proportional relationship between the lime temperature drop, the medium temperature rise, and the recovery medium temperature rise, and in conjunction 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 both the primary heat exchange efficiency coefficient and the secondary heat recovery efficiency coefficient are within the preset heat balance matching threshold range, then the high-temperature lime is determined to meet the cooling standard corresponding to the target temperature threshold; otherwise, it is determined not to meet the standard.

9. A continuous lime cooling system with dual-loop waste heat recovery, used to implement the continuous lime cooling method with dual-loop waste heat recovery as described in any one of claims 1 to 8, characterized in that, include: The parameter acquisition module is used to acquire the initial temperature parameters and mass flow rate 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 from the preset database in the lime cooling process standard. The loop construction module is used to construct a dual-loop waste heat recovery path that includes a main cooling loop and an auxiliary recovery loop. The main cooling loop is used to carry the direct contact heat exchange process between high-temperature lime and the first type of heat exchange medium, while the auxiliary recovery loop is used to carry the indirect heat conduction process between the first type of heat exchange medium and the second type of heat exchange medium. The medium control module is used to dynamically control 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 based on the difference between the initial temperature parameter and the target temperature threshold. The process monitoring module is used to collect real-time temperature data of high-temperature lime in the main cooling circuit and outlet temperature data of the first type of heat exchange medium, and simultaneously collect inlet temperature data and outlet temperature data of the second type of heat exchange medium in the auxiliary recovery circuit. The effect judgment 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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