Double-chamber lime kiln temperature monitoring and safety interlocking system and method

Abstract

The invention provides a temperature monitoring and safety interlocking system and method for a double-hearth lime kiln. The temperature monitoring and safety interlocking system is characterized in that a redundant temperature monitoring module is provided with at least two independent temperature measuring channels; the pressure monitoring module is used for collecting pressure data in the double-chamber lime kiln; the safety interlocking control module is in communication connection with the redundant temperature monitoring module, the pressure monitoring module and the emergency protection execution module, and is used for receiving the temperature data and the data, determining a risk level according to a preset hierarchical interlocking judgment rule when detecting that the temperature or the pressure is abnormal, and automatically starting a protection mechanism of a corresponding level; and the emergency protection execution module is in signal connection with the safety interlocking control module and is used for receiving a control instruction output by the safety interlocking control module and executing an emergency protection action corresponding to a protection mechanism. According to the method, misjudgment or missed judgment caused by failure of the single-point sensor is effectively avoided, and the monitoring reliability of the system is remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial kiln safety control, in particular to a double-chamber lime kiln temperature monitoring and safety interlocking system and method. BACKGROUND

[0002] As a kind of efficient energy-saving lime calcination equipment, the stable operation of double-chamber lime kiln highly depends on the accurate perception and rapid response to the temperature and pressure of the key area in the kiln, especially the suspension cylinder part. However, in the prior art, a single thermocouple is generally used for direct insertion into the kiln body for temperature monitoring. Since the calcination temperature in the kiln is long-term in a high-temperature dust environment of 1100-1200℃, the thermocouple is prone to oxidation, slagging, mechanical wear or signal drift, resulting in a significant reduction in sensor life, usually only 3 to 6 months. Frequent replacement not only increases maintenance costs, but also requires the kiln to be stopped for more than 8 hours, which seriously affects the continuity of production.

[0003] More seriously, once the single temperature measurement point fails or drifts, the system cannot effectively identify data anomalies, which can easily cause temperature monitoring errors (deviation up to ±50℃ or even higher), and further cause temperature control logic misjudgment, which can lead to under-burning or over-burning of lime, reducing product quality, or even causing equipment damage or safety accidents due to failure to identify over-temperature risks in time. At the same time, the existing safety interlocking system relies on the single temperature signal as the basis for judgment, with a false alarm rate of more than 15%, and frequent false kiln shutdown operations cause huge production losses. SUMMARY

[0004] In view of this, the present application proposes a double-chamber lime kiln temperature monitoring and safety interlocking system and method, aiming to solve the problem of low safety interlocking reliability caused by single-point failure of temperature sensors and high false alarm rate in the prior art.

[0005] The present application proposes a double-chamber lime kiln temperature monitoring and safety interlocking system, comprising: a redundant temperature monitoring module, a pressure monitoring module, a safety interlocking control module and an emergency protection execution module; wherein, The redundant temperature monitoring module is provided with at least two independent temperature measurement channels for simultaneously collecting temperature data of each preset monitoring point in the double-chamber lime kiln; The pressure monitoring module is used to collect pressure data in the double-chamber lime kiln; The safety interlocking control module is respectively connected in communication with the redundant temperature monitoring module, the pressure monitoring module and the emergency protection execution module, for receiving the temperature and pressure data, and when detecting temperature or pressure anomalies, determining the risk level according to the preset hierarchical interlocking judgment rule, and automatically starting the protection mechanism of the corresponding level; The emergency protection execution module is signal-connected to the safety interlock control module, and is used to receive control commands output by the safety interlock control module and execute emergency protection actions corresponding to the protection mechanism. The protection mechanism includes primary protection, secondary protection and ultimate protection, and the redundant temperature monitoring module, pressure monitoring module, safety interlock control module and emergency protection execution module form a complete interlock control loop from anomaly detection to protection action execution.

[0006] Furthermore, in the aforementioned double-chamber lime kiln temperature monitoring and safety interlock system, the redundant temperature monitoring module includes: a direct temperature measurement unit, an indirect temperature measurement unit, and an air temperature calculation unit; wherein, The direct temperature measurement unit is arranged on the outer wall of the suspension cylinder and is used to obtain its outer surface temperature by contact. The indirect temperature measurement unit is located on the outside of the double-chamber lime kiln and is used to obtain the temperature distribution on the outer surface of the suspension cylinder in a non-contact manner. The air temperature calculation unit is used to calculate the temperature of the inner wall of the suspension cylinder based on the air temperature sensor data in the airflow cooling channel.

[0007] Furthermore, in the above-mentioned temperature monitoring and safety interlocking system for a double-chamber lime kiln, the safety interlocking control module includes a main controller and a backup controller. The main controller is a programmable logic controller (PLC), and the backup controller is a distributed control system (DCS). A status synchronization interface is provided between the main controller and the backup controller to automatically switch to the backup controller when the main controller fails, with a switching time of no more than 50ms.

[0008] Furthermore, in the aforementioned double-chamber lime kiln temperature monitoring and safety interlock system, the emergency protection execution module includes: an audible and visual alarm unit, a gas shut-off valve, an emergency pressure relief valve, a fusible temperature circuit breaker, and a water-cooled emergency unit; wherein, The control terminal of the audible and visual alarm unit is connected to the output terminal of the safety interlock control module, and is used to issue a warning signal when the temperature exceeds the first threshold. The gas shut-off valve and the emergency pressure relief valve are linked together, and the control terminals of both are connected to the output signal of the safety interlock control module. When an interlock command is received that the temperature exceeds the second threshold or the pressure inside the kiln exceeds the set pressure value, the gas supply is shut off and the pressure inside the kiln is released simultaneously. The fusible temperature circuit breaker is connected in series in the main power supply circuit of the system to cut off the system power supply when the temperature exceeds the material safety limit; The control terminal of the water-cooled emergency unit is connected to the output terminal of the safety interlock control module, and is used to start within 3 seconds after receiving an emergency stop command, with a cooling water flow rate of not less than 25 m³ / h.

[0009] Furthermore, in the above-mentioned double-chamber lime kiln temperature monitoring and safety interlock system, the first threshold is 1000℃, the second threshold is 1200℃, and the set pressure value is 0.35MPa.

[0010] Furthermore, in the aforementioned double-chamber lime kiln temperature monitoring and safety interlock system, the safety interlock control module is also electrically connected to the feeding mechanism and the airlock mechanism, and is used to control the feeding mechanism and the airlock mechanism to work together in real time: when the feeding hole is open, the airlock mechanism is activated; when the feeding hole is closed, the airlock mechanism is deactivated.

[0011] The temperature monitoring and safety interlocking system for a double-chamber lime kiln provided in this invention, by setting up redundant temperature and pressure monitoring modules and combining them with a safety interlocking control module, classifies abnormal operating conditions according to graded interlocking judgment rules, and links the emergency protection execution module to perform corresponding actions. The modules form a closed-loop interlocking control circuit, which can maintain effective monitoring even when a single sensor fails, significantly reducing false alarms or missed alarms caused by inaccurate data, keeping the false alarm rate of safety interlocking at a low level, and ensuring that the corresponding level of protection mechanism is quickly activated in dangerous operating conditions such as abnormal temperature or pressure. Thus, while improving the safety level, it ensures the continuous and stable operation of the double-chamber lime kiln.

[0012] On the other hand, the present invention also proposes a safety interlock control method for a double-chamber lime kiln, comprising the following steps: The temperature and pressure data of each preset monitoring point in the double-chamber lime kiln are collected in real time, and the temperature data is acquired synchronously through at least two independent temperature measurement channels. The temperature and pressure data are compared with preset multi-level safety thresholds to determine the risk level of the current operating state. The corresponding level of protection mechanism is automatically activated based on the risk level, and emergency operations matching the protection mechanism are executed; wherein, the protection mechanism includes level one protection, level two protection, and ultimate protection; After the emergency operation is completed, temperature and pressure data are continuously collected and compared with the multi-level safety thresholds to form a closed-loop interlocking control process from anomaly identification, graded response to protection execution.

[0013] Furthermore, in the above-mentioned safety interlock control method for a double-chamber lime kiln, the primary protection includes triggering an audible and visual alarm device and adjusting the gas flow rate; The secondary protection includes activating the emergency stop system and opening the emergency pressure relief valve; The ultimate protection includes switching to a backup distributed control system in the event of a failure of the main controller, and cutting off the main power supply by a fusible temperature circuit breaker when the temperature exceeds the material safety limit.

[0014] Furthermore, in the above-mentioned safety interlock control method for a double-chamber lime kiln, the primary protection is triggered when the monitored parameters exceed the first safety threshold, and the response time does not exceed the first preset duration; The secondary protection is triggered when the monitored parameters exceed the second safety threshold, and the response time does not exceed the second preset duration. The ultimate protection is triggered when the monitoring parameters reach the material safety limit or the control system fails, and the response time does not exceed the third preset duration. The third preset duration is shorter than the second preset duration, and the second preset duration is shorter than the first preset duration.

[0015] Furthermore, in the above-mentioned safety interlock control method for double-chamber lime kilns, after any protection mechanism is completed, the operating status of the double-chamber lime kiln is continuously monitored; when the monitoring parameters return to a safe range and the fault status is cleared, the system returns to normal operation mode after a reset operation.

[0016] The safety interlock control method for a double-chamber lime kiln provided by this invention collects temperature and pressure data from preset monitoring points in real time, and dynamically determines the risk level based on multi-level safety thresholds, thereby triggering corresponding first-level protection, second-level protection, or ultimate protection mechanisms. This achieves graded, precise, and rapid risk response. At the same time, it automatically returns to the data acquisition stage after emergency operation is completed, forming a closed-loop monitoring and control process, effectively avoiding delays or omissions caused by manual intervention, and significantly improving the safety and operational reliability of the system. Attached Figure Description

[0017] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 Structural block diagram of the temperature monitoring and safety interlocking system for a double-chamber lime kiln provided in this embodiment of the invention. Figure 2 This is a flowchart illustrating the working process of the temperature monitoring and safety interlocking system for a double-chamber lime kiln in this embodiment of the invention. Figure 3 This is a flowchart of the temperature monitoring and safety interlock control method for a double-chamber lime kiln in an embodiment of the present invention. Detailed Implementation

[0018] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] System Implementation Examples See Figure 1 The temperature monitoring and safety interlocking system for a double-chamber lime kiln according to an embodiment of the present invention includes: a redundant temperature monitoring module, a pressure monitoring module, a safety interlocking control module, and an emergency protection execution module. The redundant temperature monitoring module has at least two independent temperature measurement channels for synchronously collecting temperature data from preset monitoring points within the double-chamber lime kiln. The pressure monitoring module collects pressure data within the double-chamber lime kiln. The safety interlocking control module is communicatively connected to the redundant temperature monitoring module, the pressure monitoring module, and the emergency protection execution module, respectively, for receiving the temperature and pressure data, and, upon detecting abnormal temperature or pressure, determining the risk level according to preset graded interlocking judgment rules and automatically activating the corresponding level of protection mechanism. The emergency protection execution module is signal-connected to the safety interlocking control module, for receiving control commands output by the safety interlocking control module, and executing emergency protection actions corresponding to the protection mechanism. The protection mechanism includes primary protection, secondary protection, and ultimate protection, and the redundant temperature monitoring module, pressure monitoring module, safety interlocking control module, and emergency protection execution module form a complete interlocking control loop from abnormal detection to protection action execution.

[0020] Specifically, the redundant temperature monitoring module is equipped with at least two independent temperature measurement channels, each employing different temperature measurement principles or paths to collect data. This enables synchronous monitoring of the temperature at various monitoring points within the double-chamber lime kiln (such as the suspension cylinder, the outside of the kiln chamber, and the airflow cooling channel). This effectively avoids misjudgments or missed reports caused by single-point sensor failures, improving the reliability and safety of temperature monitoring. In this embodiment, three temperature measurement channels are selected: the suspension cylinder, the outside of the kiln chamber, and the airflow cooling channel.

[0021] More specifically, the redundant temperature monitoring module includes: a direct temperature measurement unit, an indirect temperature measurement unit, and an air temperature estimation unit; wherein, the direct temperature measurement unit is arranged on the outer wall of the suspension cylinder for contact acquisition of its outer surface temperature; the indirect temperature measurement unit is located on the outside of the double-chamber lime kiln for non-contact acquisition of the temperature distribution on the outer surface of the suspension cylinder; the air temperature estimation unit is used to estimate the temperature of the inner wall of the suspension cylinder based on the air temperature sensor data in the airflow cooling channel; the output terminals of the direct temperature measurement unit, the indirect temperature measurement unit, and the air temperature estimation unit are all connected to the safety interlock control module for signal connection, and are used to fuse multi-source temperature data for anomaly diagnosis.

[0022] In one embodiment, the redundant temperature monitoring module has four K-type thermocouples arranged at the top of the suspension cylinder to monitor the temperature of the upper wall surface of the cylinder; and eight K-type thermocouples arranged at the bottom of the suspension cylinder to monitor the temperature of the lower wall surface of the cylinder. All thermocouples have a measurement accuracy of ±1.5℃ and a sampling frequency of 10Hz, forming a contact temperature measurement channel to acquire internal wall temperature data in real time.

[0023] Two infrared thermal imagers are installed on the outside of the kiln cavity to scan the temperature distribution on the kiln surface in a non-contact manner, generating a two-dimensional temperature field image to help identify local hot spots.

[0024] Twelve air temperature sensors were installed within the airflow cooling duct to collect temperature data at various points along the duct. Based on a heat conduction model, the estimated average wall temperature T of the suspension cylinder was calculated. w ′, its formula is: Among them, t i The wind temperature measured by i wind temperature sensors, k i Where is the thermal conductivity and C is the environmental correction factor.

[0025] The redundant temperature monitoring module transmits temperature data from each temperature measurement channel to the safety interlock control module. The safety interlock control module fuses the received multi-source temperature data and executes an anomaly diagnosis mechanism based on logarithmic temperature rise for each temperature monitoring point within the double-chamber lime kiln. Specifically, this includes: acquiring the temperature time series of each region and calculating its temperature rise rate; comparing the temperature rise rate with the baseline temperature rise rate curve of the corresponding monitoring region in the current process stage stored in the database; if the relative deviation exceeds a preset threshold (e.g., 15%), it is determined that the region has an abnormal temperature rise trend, is marked as an over-temperature region, and a graded early warning or interlock protection mechanism is triggered based on the degree of deviation. The baseline temperature rise rate curve is obtained by collecting temperature data from the double-chamber lime kiln under stable operating conditions and performing numerical differentiation processing.

[0026] In a preferred embodiment of the present invention, the safety interlock control module performs an anomaly diagnosis mechanism based on logarithmic temperature rise for each temperature monitoring zone within the double-chamber lime kiln, specifically including the following steps: Obtain the temperature time series T(t) for each region and calculate its logarithmic temperature rise rate a. i The logarithmic rate of temperature rise is defined as the rate of change of the logarithm of temperature over time.

[0027] Logarithmic temperature rise a i The calculation formula is as follows: a i= in, The sampling interval (e.g., 0.1 seconds); Then, the calculated a i The curve is compared with the baseline curve of the corresponding area in the same stage in the database. If the relative deviation exceeds the preset threshold (e.g., 15%), the area is marked as an over-temperature area and the corresponding protection mechanism is triggered according to the risk level: a slight deviation triggers an audible and visual alarm, and a serious over-limit triggers protective actions such as gas cut-off and emergency pressure relief.

[0028] In this embodiment, the pressure monitoring module includes multiple pressure sensors, which are respectively arranged in the combustion chamber, flue gas passage, and airflow cooling channel of the kiln body to monitor local positive or negative pressure changes. When an abnormal pressure occurs (such as a sudden drop in negative pressure or an abnormal increase in positive pressure), the system can issue a pressure warning.

[0029] In this embodiment of the invention, the graded interlocking judgment rule refers to a multi-level triggering condition based on risk level classification, including a first-level protection rule (such as temperature > 1000℃ or pressure > 0.25MPa), a second-level protection rule (such as temperature > 1200℃ or pressure > 0.35MPa), and a final protection rule (such as temperature > the limit temperature for safe use of kiln body materials), which is used to drive corresponding emergency protection actions.

[0030] In this invention, the safety interlock control module includes a main controller and a backup controller. The main controller is a programmable logic controller (PLC), and the backup controller is a distributed control system (DCS). A state synchronization interface is provided between the main controller and the backup controller to automatically switch to the backup controller when the main controller fails, with a switching time of no more than 50ms.

[0031] In practical implementation, the main controller is a high-reliability programmable logic controller (PLC), preferably an industrial-grade PLC with hardware redundancy (such as the Siemens S7-400H series), which is used to receive data from redundant temperature monitoring modules and pressure monitoring modules in real time, execute anomaly diagnosis algorithms, and output interlocking control commands to the emergency protection execution module.

[0032] The backup controller is a distributed control system (DCS) that periodically synchronizes its operating status, diagnostic results, and key process data with the main controller via a high-speed communication interface. When the main controller experiences a hardware failure, communication interruption, or program abnormality, the system automatically switches to the backup controller within 50 milliseconds, and the DCS seamlessly takes over all safety interlock functions.

[0033] In addition, the safety interlock control module is also equipped with a human-machine interface (HMI), such as a monitoring system based on the WINCC platform, which is used to display the temperature curves, pressure trends, over-temperature alarm status and main / backup controller switching records of each monitoring area in real time, so as to facilitate operator monitoring and fault tracing.

[0034] In the above embodiments, the emergency protection execution module includes: an audible and visual alarm unit, a gas shut-off valve, an emergency pressure relief valve, a fusible temperature circuit breaker, and a water-cooled emergency unit; wherein, the control terminal of the audible and visual alarm unit is connected to the output terminal of the safety interlock control module, and is used to issue a warning signal when the temperature exceeds a first threshold; the gas shut-off valve and the emergency pressure relief valve are linked, and their control terminals are both connected to the output terminal of the safety interlock control module, and are used to simultaneously execute gas supply cut-off and kiln pressure release operations when receiving an interlock command that the temperature exceeds a second threshold or the kiln pressure exceeds a set pressure value; the fusible temperature circuit breaker is connected in series in the main power supply circuit of the system, and is used to cut off the system power supply when the temperature exceeds the material safety limit; the control terminal of the water-cooled emergency unit is connected to the output terminal of the safety interlock control module, and is used to start within 3 seconds after receiving an emergency stop command, with a cooling water flow rate of not less than 25 m³ / h.

[0035] Specifically, the first threshold is 1000℃, the second threshold is 1200℃, and the set pressure value is 0.35MPa.

[0036] In practice, when the system detects that the temperature in any monitored area within the kiln (such as the top or bottom of the suspension cylinder) exceeds the first threshold (e.g., 1000℃), the safety interlock control module triggers the audible and visual alarm unit, issuing an audible and visual warning signal to alert operators to the abnormal temperature rise trend. At this time, the system remains controllable and can be restored by adjusting parameters. When the kiln temperature exceeds the second threshold (e.g., 1200℃), or the kiln pressure exceeds the set pressure value (e.g., 0.35 MPa), the safety interlock control module immediately outputs an interlock command, simultaneously closing the gas shut-off valve and opening the emergency pressure relief valve. The emergency pressure relief valve automatically opens when the kiln pressure reaches its opening pressure (e.g., 0.35 MPa), releasing overpressured gas and preventing equipment damage due to overpressure.

[0037] When the local temperature exceeds the material's safety limit due to an extreme fault, the internal fuse element of the fusible temperature circuit breaker will automatically melt, forcibly cutting off the power supply to the entire machine and preventing the equipment from burning out or causing a fire.

[0038] When the system receives an emergency stop command, the water-cooled emergency unit will automatically start within 3 seconds, spraying cooling water onto critical high-temperature areas such as the outer wall of the suspension cylinder. The cooling water flow rate is no less than 25 m³ / h to quickly reduce the surface temperature of the equipment and prevent damage to the equipment materials.

[0039] In the above embodiments, the safety interlock control module is also electrically connected to the feeding mechanism and the airlock mechanism, and is used to control the feeding mechanism and the airlock mechanism to work together in real time: when the feeding hole is open, the airlock mechanism is activated; when the feeding hole is closed, the airlock mechanism is deactivated.

[0040] Specifically, when the feeding mechanism opens the feeding hole to discharge material, the safety interlock control module outputs a control signal simultaneously to drive the airlock mechanism to open, so as to balance the airflow in the kiln and prevent flame overflow or air backflow caused by negative pressure fluctuations; when the feeding mechanism closes the feeding hole, the airlock mechanism closes simultaneously to ensure the kiln's airtightness.

[0041] From the above, it is clear that the temperature monitoring and safety interlocking system for the double-chamber lime kiln provided in this embodiment, by setting up redundant temperature monitoring modules and pressure monitoring modules, combined with the safety interlocking control module to classify abnormal operating conditions according to the graded interlocking judgment rules, and linking the emergency protection execution module to execute corresponding actions, and the modules forming a closed-loop interlocking control loop, can still maintain effective monitoring even when a single-point sensor fails, significantly reducing false judgments or missed judgments caused by inaccurate data, keeping the false alarm rate of safety interlocking at a low level, and ensuring that the corresponding level of protection mechanism is quickly activated in dangerous operating conditions such as abnormal temperature or pressure, thereby improving the safety level and ensuring the continuous and stable operation of the double-chamber lime kiln.

[0042] See Figure 2The working process of the double-chamber lime kiln temperature monitoring and safety interlock system described in this invention is as follows: First, multi-source temperature data is collected from key areas of the lime kiln (such as the wall of the suspension cylinder and the outlet of the cooling channel) through redundant temperature monitoring modules, including contact thermocouple temperature measurement, non-contact infrared thermal imaging temperature measurement, and wall temperature calculated based on cooling air temperature.

[0043] Temperature data is transmitted in real time to the safety interlock control module, which performs data fusion and anomaly diagnosis: the system calculates the logarithmic temperature rise 'a' for each temperature time series. i It is then compared with a pre-stored baseline curve; if the deviation exceeds a set threshold (e.g., 15%), it is determined to be an abnormal temperature rise and triggers an over-temperature warning.

[0044] Once a safety risk is confirmed, the safety interlock control module immediately generates and outputs an interlock control command, initiating the safety interlock trigger phase. This command automatically selects the corresponding protection level based on the anomaly level, ensuring timely response and precise action.

[0045] Subsequently, the emergency protection execution module receives instructions and executes corresponding emergency actions, including but not limited to: triggering audible and visual alarms, cutting off gas supply, opening emergency pressure relief valves, starting water cooling systems, or, in extreme cases, directly cutting off the main power supply through a fusible temperature circuit breaker, thereby achieving graded and orderly safety protection.

[0046] After the abnormal operating conditions are resolved and the kiln temperature returns to a safe range, the system automatically or with manual confirmation enters the system status recovery phase, re-enters the normal monitoring mode, and completes a complete closed-loop interlocking control process.

[0047] The above process constitutes a real-time, closed-loop, and redundant safety interlock control link, which can provide early warning of temperature anomalies and automatically execute multi-level protection measures under abnormal operating conditions, significantly improving the safety of double-chamber lime kiln operation.

[0048] In summary, the dual-chamber lime kiln temperature monitoring and safety interlocking system of this invention achieves a suspension cylinder temperature measurement error of ≤±2% by integrating direct temperature measurement and air temperature estimation models through redundant temperature monitoring modules; it achieves switching within 50ms in case of system failure through the coordination of the safety interlocking control module and the main / standby redundant architecture, avoiding control interruption; it achieves synchronous operation of the material feeding, air lock, and gas systems by linking the emergency protection execution module according to the hierarchical interlocking judgment rules, reducing heat loss and reducing measured energy consumption by 12%; and it achieves three levels of protection from first-level early warning, second-level intervention to final forced power failure through a closed-loop interlocking control circuit composed of redundant temperature monitoring modules, pressure monitoring modules, safety interlocking control modules, and emergency protection execution modules, reducing the risk of thermal runaway by more than 90%.

[0049] Method Implementation Examples See Figure 3 The safety interlock control method for a double-chamber lime kiln provided by the present invention includes the following steps: Step S1: Real-time acquisition of temperature and pressure data at each preset monitoring point inside the double-chamber lime kiln. The temperature data is acquired synchronously through at least two independent temperature measurement channels.

[0050] Specifically, the preset monitoring points include key locations prone to overheating or overpressure, such as the inner wall of the suspension cylinder, the outlet of the cooling air duct, the pressure measuring point in the kiln chamber, and the vicinity of the fuel inlet. Temperature data is acquired jointly by a K-type thermocouple array and an infrared thermal imager, while pressure data is collected in real time by a high-precision pressure transmitter. The temperature data is acquired through at least two independent temperature measurement channels to achieve redundant monitoring.

[0051] In practice, after the system starts up, it enters a continuous real-time monitoring cycle. Temperature data is collected jointly by a K-type thermocouple array arranged on the wall of the suspension cylinder, an infrared thermal imager on the outside of the kiln, and a wind temperature sensor in the airflow cooling channel; pressure data is acquired in real time by a pressure sensor inside the kiln. All sensor signals are uniformly input to the main controller (such as a PLC or DCS), forming a multi-source, highly reliable monitoring data stream for subsequent judgment.

[0052] Step S2: The temperature data and pressure data are compared with preset multi-level safety thresholds to identify the current risk level.

[0053] Specifically, the first-level protection is triggered when the monitored parameter exceeds the first safety threshold, and the response time does not exceed the first preset duration; the second-level protection is triggered when the monitored parameter exceeds the second safety threshold, and the response time does not exceed the second preset duration; the ultimate protection is triggered when the monitored parameter reaches the material safety limit or the control system fails, and the response time does not exceed the third preset duration. The third preset duration is shorter than the second preset duration, and the second preset duration is shorter than the first preset duration.

[0054] More specifically, the first safety threshold is set as: temperature > 1000℃ or pressure > 0.25MPa; the second safety threshold is set as: temperature > 1200℃ or pressure > 0.35MPa; the material safety limit is set as: temperature > the limit temperature for safe use of the kiln body material. Furthermore, a failure in the main control system is also considered a condition for triggering the ultimate protection. The first preset duration is 1 second, the second preset duration is 0.5 seconds, and the third preset duration is 50 milliseconds, with the response time decreasing as the risk level increases.

[0055] In specific implementation, the first-level protection mechanism is as follows: when the monitored temperature or pressure exceeds the first safety threshold, it is determined to be a minor over-limit. The system triggers an audible and visual alarm, automatically adjusts the gas flow to reduce the heat load, and records the event log. The entire process is completed within 1 second, allowing the system to automatically return to normal operation through external intervention. The second-level protection mechanism is as follows: when the monitored parameter exceeds the second safety threshold, it is determined to be a serious over-limit, potentially causing danger. The system immediately performs an emergency stop and pressure relief, cuts off the fuel supply, and opens the emergency pressure relief valve to release the pressure inside the kiln. The response time is shortened to 0.5 seconds to prevent equipment damage or the escalation of the accident. Ultimate protection: when the monitored parameter reaches the material safety limit or the control system itself malfunctions, the system executes the highest priority protection actions, including the activation of the fusible temperature circuit breaker to force a power outage and seamlessly switch to the backup control system (DCS), taking only about 50 milliseconds.

[0056] When any of the monitored parameters meet the conditions, the system automatically determines the corresponding risk level and triggers the corresponding protection mechanism.

[0057] Step S3: Automatically activate the corresponding level of protection mechanism according to the risk level, and execute emergency operations matching the protection mechanism; wherein, the protection mechanism includes level one protection, level two protection and ultimate protection.

[0058] Specifically, the first-level protection includes triggering an audible and visual alarm device and adjusting the gas flow rate; the specific actions include: triggering the audible and visual alarm device to alert the operator; automatically adjusting the gas flow valve to reduce the combustion intensity; and recording the event log with a response time of ≤ 1 second.

[0059] The secondary protection includes activating the emergency stop system and opening the emergency pressure relief valve; specific actions include: activating the emergency stop system to cut off the fuel supply; opening the emergency pressure relief valve to release the pressure inside the kiln; recording the event log with a response time of ≤ 0.5 seconds.

[0060] The ultimate protection includes switching to a backup distributed control system in the event of a main controller failure, and cutting off the main power supply by a fusible thermal circuit breaker when the temperature exceeds the material's safety limit. Specific actions include: the fusible thermal circuit breaker trips, forcibly cutting off the main power supply; automatically switching to the backup distributed control system (DCS) to maintain basic monitoring functions; and recording event logs with a response time ≤ 50 milliseconds.

[0061] Step S4: After the emergency operation is completed, temperature and pressure data are collected synchronously and continuously and compared with the multi-level safety thresholds to form a closed-loop interlocking control process from anomaly identification, graded response to protection execution.

[0062] Specifically, after any protection mechanism is completed, the operating status of the double-chamber lime kiln is continuously monitored; when the monitoring parameters return to a safe range and the fault status is resolved, the system returns to normal operation mode after a reset operation.

[0063] In practice, the system continuously monitors temperature and pressure changes inside the double-chamber lime kiln. When the parameters return to a safe range and the fault has been eliminated, the system re-enters normal operation mode upon manual confirmation or automatic reset command, completing a full safety interlock control cycle.

[0064] The relevant parts of the method embodiments and the system embodiments described above can be referred to each other, and will not be repeated here.

[0065] In summary, this invention achieves graded, precise, and rapid risk response by real-time acquisition of temperature and pressure data at preset monitoring points in a double-chamber lime kiln and dynamic determination of risk levels based on multi-level safety thresholds, thereby triggering corresponding first-level, second-level, or ultimate protection mechanisms. Simultaneously, it automatically returns to the data acquisition stage after emergency operations are completed, forming a closed-loop monitoring and control process. This effectively avoids delays or omissions caused by manual intervention, significantly improving the inherent safety and operational reliability of the system.

[0066] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A dual shaft lime kiln temperature monitoring and safety interlock system, characterized in that, The application relates to a double-chamber lime kiln safety interlocking control system. The system comprises a redundant temperature monitoring module, a pressure monitoring module, a safety interlocking control module and an emergency protection execution module. The redundant temperature monitoring module is provided with at least two independent temperature measurement channels for synchronously collecting temperature data of each preset monitoring point in the double-chamber lime kiln. The pressure monitoring module is used for collecting pressure data in the double-chamber lime kiln. The safety interlocking control module is in communication connection with the redundant temperature monitoring module, the pressure monitoring module and the emergency protection execution module, is used for receiving the temperature data and the pressure data, and when detecting temperature or pressure abnormality, determines a risk level according to preset grading interlocking judgment rules, and automatically starts a protection mechanism of a corresponding level. The emergency protection execution module is in signal connection with the safety interlocking control module, is used for receiving a control instruction output by the safety interlocking control module, and executes an emergency protection action corresponding to the protection mechanism. The protection mechanism comprises a first-level protection, a second-level protection and a final protection, and the redundant temperature monitoring module, the pressure monitoring module, the safety interlocking control module and the emergency protection execution module form a complete interlocking control loop from abnormality detection to protection action execution.

2. The dual chamber lime kiln temperature monitoring and safety interlock system of claim 1, wherein, The redundant temperature monitoring module comprises a direct temperature measurement unit, an indirect temperature measurement unit and a wind temperature calculation unit. The direct temperature measurement unit is arranged on the outer wall of the suspension cylinder and is used for contact type acquisition of the outer surface temperature. The indirect temperature measurement unit is arranged on the outer side of the double-chamber lime kiln and is used for non-contact type acquisition of the temperature distribution of the outer surface of the suspension cylinder. The wind temperature calculation unit is used for calculating the temperature of the inner wall surface of the suspension cylinder according to the wind temperature sensor data in the airflow cooling channel.

3. The dual chamber lime kiln temperature monitoring and safety interlock system of claim 1, wherein, The safety interlocking control module comprises a main controller and a backup controller.

4. The dual chamber lime kiln temperature monitoring and safety interlock system of claim 1, wherein, The main controller is a programmable logic controller (PLC), the backup controller is a distributed control system (DCS), and a state synchronization interface is arranged between the main controller and the backup controller, so that the backup controller can be automatically switched when the main controller fails, and the switching time is not more than 50 ms. The emergency protection execution module comprises an audible and visual alarm unit, a gas cut-off valve, an emergency pressure relief valve, a fuse type temperature circuit breaker and a water cooling emergency unit. The control end of the audible and visual alarm unit is in signal connection with the output end of the safety interlocking control module, and is used for sending a pre-warning signal when the temperature exceeds a first threshold value. The gas cut-off valve and the emergency pressure relief valve are in linkage, and the control ends of the two are in signal connection with the output end of the safety interlocking control module, and are used for synchronously executing gas supply cut-off and kiln pressure release operation when receiving an interlocking instruction that the temperature exceeds a second threshold value or the kiln pressure exceeds a set pressure value. The fuse type temperature circuit breaker is arranged in series in a system main power supply loop, and is used for cutting off the system power supply when the temperature exceeds a material safety limit. The control end of the water cooling emergency unit is in signal connection with the output end of the safety interlocking control module, and is used for starting within 3 seconds after receiving an emergency stop instruction, and the cooling water flow is not less than 25 m3 / h.

5. The dual chamber lime kiln temperature monitoring and safety interlock system of claim 4, wherein, The first threshold value is 1000℃, the second threshold value is 1200℃, and the set pressure value is 0.35MPa.

6. The dual chamber lime kiln temperature monitoring and safety interlock system of claim 1, wherein, The safety interlocking control module is also electrically connected with the discharging mechanism and the air locking mechanism, and is used for controlling the real-time linkage of the discharging mechanism and the air locking mechanism: when the discharging hole is opened, the air locking mechanism is opened; when the discharging hole is closed, the air locking mechanism is closed.

7. A safety interlock control method for a twin shaft lime kiln, characterized by, The method comprises the following steps: Real-time acquisition of temperature and pressure data of each preset monitoring point in the double-chamber lime kiln, wherein the temperature data is synchronously acquired through at least two independent temperature measurement channels; The temperature data and the pressure data are compared with preset multi-level safety threshold values respectively to determine the risk level to which the current operating state belongs; According to the risk level, a corresponding level of protection mechanism is automatically started, and an emergency operation matched with the protection mechanism is executed; wherein the protection mechanism comprises a first-level protection, a second-level protection and an ultimate protection; After the execution of the emergency operation is completed, the acquisition of the temperature and pressure data and the comparison with the multi-level safety threshold values are synchronously and continuously performed, forming a closed-loop interlocking control process from abnormality identification, graded response to protection execution.

8. The safety interlocking control method of the double-chamber lime kiln according to claim 7, wherein, The first-level protection comprises triggering an audible and visual alarm device and adjusting the gas flow; The second-level protection comprises starting an emergency stop system and opening an emergency pressure relief valve; The ultimate protection comprises switching to a backup distributed control system when the main controller fails, and cutting off the main power supply by a fuse-type temperature circuit breaker when the temperature exceeds the material safety limit.

9. The safety interlocking control method of the double-chamber lime kiln according to claim 7, wherein, The first-level protection is triggered when the monitoring parameter exceeds the first safety threshold value, and the response time is not more than a first preset time length; The second-level protection is triggered when the monitoring parameter exceeds the second safety threshold value, and the response time is not more than a second preset time length; The ultimate protection is triggered when the monitoring parameter reaches the material safety limit or the control system fails, and the response time is not more than a third preset time length; The third preset time length is shorter than the second preset time length, and the second preset time length is shorter than the first preset time length.

10. The safety interlock control method of a twin chamber lime kiln according to claim 7, characterized in that, After the execution of any protection mechanism is completed, the operating state of the double-chamber lime kiln is continuously monitored; when the monitoring parameter returns to the safety range and the fault state is eliminated, the system returns to the normal operating mode after a reset operation.

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