A Temperature Monitoring Method, System and Storage Medium for a Double-chamber Lime Kiln Suspension Cylinder

Abstract

The present invention discloses a method, a system and a storage medium for monitoring the temperature of a suspension cylinder of a double-shaft lime kiln, comprising the following steps: S1, obtaining the air temperature ti of each temperature measurement point i in the air-cooling flow channel of the suspension cylinder i ; S2, using the formula a j = t i+1 - t i , obtaining the average temperature rise aj of the temperature measurement interval j j ; according to the average temperature rise curve corresponding to the average temperature rise aj j , determining the average temperature rise a j that deviates from the average temperature rise curve by more than a preset threshold as an abnormal temperature rise, and obtaining the area corresponding to the abnormal temperature rise as an over-temperature area. The method for monitoring the temperature of the suspension cylinder of the double-shaft lime kiln of the present invention makes the abnormal temperature rise change significantly by using the mean value screening method and the change of the average temperature rise, determines the local over-temperature area, is more sensitive to the capture and monitoring of the local over-temperature of the suspension cylinder, can provide timely early warning for the production site, and thus effectively prolongs the service life of the suspension cylinder.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature monitoring of the suspension cylinder of a double-shaft lime kiln, and in particular, to a method, a system and a storage medium for monitoring the temperature of the suspension cylinder of a double-shaft lime kiln. Background Art

[0002] The double-shaft lime kiln is one of the most advanced lime production equipments at present and is widely used in the production of industrial lime and building lime. It mainly consists of two vertical kiln chambers that are mirror images of each other. During the production process, pulverized coal and combustion-supporting air are supplied into one side of the kiln chamber to form a high-temperature environment, so that the limestone in the kiln chamber is decomposed at high temperature, which is called the calcination chamber; normal-temperature materials are loaded into the other side of the kiln chamber, and at the same time, the high-temperature flue gas formed in the combustion chamber is introduced from the bottom and discharged from the top to achieve the effect of preheating the materials. This side of the kiln chamber is called the regenerative chamber. After a cycle (about 14 minutes), the two kiln chambers exchange roles with each other to realize the continuous production of lime. Due to its double-shaft calcination - periodic commutation process, the high-temperature flue gas generated by calcination and the high-temperature waste gas formed by the cooling of the finished product are used to preheat the materials and then discharged from the kiln chamber. The exhaust gas temperature can usually be reduced to about 120°C, so it has a very high heat utilization rate.

[0003] In the prior art, a suspension cylinder-type annular channel is provided between the combustion chamber and the regenerative chamber to connect the air channels of the two parallel kiln chambers, so that the high-temperature flue gas can flow smoothly from one chamber into the other. The suspension cylinder-type annular channel is surrounded by two layers of steel shells, and refractory and heat-insulating materials are built or poured outside the steel shells. An annular cavity is formed inside the two layers of steel shells. Since the working temperature outside the refractory material is as high as 1100°C, in order to prevent the strength of the steel from decreasing at high temperature, it is usually necessary to force air ventilation to cool the annular cavity to ensure that the temperature of the steel shell does not become too high. During the production process, due to wear or cracking of the heat-insulating material outside the steel shell, the local temperature of the steel shell will exceed the limit, resulting in structural failure and damage. Therefore, it is very important to monitor and warn the temperature of the suspension cylinder shell.

[0004] At present, the method of setting thermocouple thermometers at local positions is mainly used for monitoring. The temperature of several local points is used to replace the temperature of the whole suspension cylinder. When the temperature of the temperature measurement point exceeds the limit, a warning is issued. However, when local overheating occurs at positions outside the temperature measurement point, effective warning cannot be given, resulting in the technical problem that the local overheating affecting the service life of the suspension cylinder cannot be effectively captured. Summary of the Invention

[0005] The method for monitoring the temperature of the suspension cylinder of the double-shaft lime kiln provided by the present invention solves the technical problem that local overheating cannot be effectively captured during the existing temperature monitoring of the suspension cylinder.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for monitoring the temperature of a suspension cylinder of a double-shaft lime kiln. There are multiple temperature measurement points in the air flow cooling channel of the suspension cylinder, and the streamline lengths between adjacent two temperature measurement points are the same. Define i as the temperature measurement point number, i ∈ [0, N]. The temperature measurement points are numbered in sequence along the air flow direction in the air flow cooling channel. 0 represents the number of the first temperature measurement point, and N represents the number of the last temperature measurement point. Define that N + 1 temperature measurement points divide the air flow cooling channel into N temperature measurement intervals j, j = i + 1, j ∈ [1, N], j is the temperature measurement interval number, and the temperature measurement interval number between temperature measurement point i and temperature measurement point i + 1 is j. The method includes the following steps: S1, obtain the air temperature t of each temperature measurement point i in the air flow cooling channel of the suspension cylinder i ; S2, use the formula a j = t i+1 - t i , obtain the average temperature rise a j of the temperature measurement interval j; According to the average temperature rise curve corresponding to the average temperature rise a j , determine the average temperature rise a j that deviates more than the preset threshold on the average temperature rise curve as the abnormal temperature rise, and obtain the area corresponding to the abnormal temperature rise as the over-temperature area.

[0008] Further, it also includes the step: S31, use the formula to calculate the estimated average wall temperature T' w of the suspension cylinder, where T' w represents the estimated average wall temperature, t 0 represents the air temperature of the temperature measurement point at the air inlet of the air flow cooling channel, t N represents the air temperature of the temperature measurement point at the air outlet of the air flow cooling channel, h is the heat transfer coefficient between the cooling air flow and the wall surface, A is the total heat transfer area, m is the air flow rate of the cooling air flow, c p is the specific heat of the air.

[0009] Further, step S2 specifically includes: S21, use the formula a j = t i+1 - t i , obtain the average temperature rise a j of the temperature measurement interval j; S22, perform linear fitting on the sequence of the average temperature rise a j to obtain the first fitting linear line, y 1 = c 1 ·x 1 + b 1 ; S23, obtain the fitting projection distance d j corresponding to each average temperature rise a j on the first fitting linear line; S24, obtain the average projection value d' according to the fitting projection distance d j ; S25, use the preset formula From each average temperature rise a j obtain the average temperature rise a that satisfies the corresponding preset formula j as the abnormal temperature rise, where the range value of the first threshold k 1 is from 1.5 to 3; S26, determine the area corresponding to the abnormal temperature rise as the over-temperature area.

[0010] Further, it further includes the step: S4, after removing all abnormal temperature rises from each average temperature rise a j perform linear fitting to obtain the second fitting linear line, y 2 = c 2 ·x 2 + b 2 .

[0011] Further, it further includes the step: S32, use the formula to calculate and obtain the corrected wall average temperature T″ w , where the corrected wall average temperature is the actual average wall temperature, where Δx is the streamline length of the temperature measurement interval, and / or step S5, use the formula to calculate and obtain the local temperature T wc (i + 1) corresponding to each abnormal temperature rise, where Δx is the streamline length of the temperature measurement interval.

[0012] The present invention also provides a double-chamber lime kiln suspension cylinder temperature monitoring system, including a temperature sensor and a suspension cylinder with an air flow cooling channel. The temperature sensors are arranged in one-to-one correspondence with the temperature measurement points. The temperature sensors are used to monitor the temperature of the corresponding temperature measurement points. Multiple temperature sensors are arranged at intervals along the extension direction of the air flow cooling channel. The streamline lengths between adjacent two temperature sensors are the same. It further includes a calculator device. The calculator device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the double-chamber lime kiln suspension cylinder temperature monitoring method based on wet capacity performance according to any one of claims 1 to 6.

[0013] Further, the air flow cooling channel adopts a spiral cooling channel. The spiral cooling channel includes a spiral inlet channel and a spiral outlet channel. An air inlet is provided at the top of the spiral inlet channel, and an air outlet is provided at the top of the spiral outlet channel. The spiral inlet channel and the spiral outlet channel are interconnected from the bottom of the suspension cylinder.

[0014] Further, the air flow cooling channel adopts an annular cooling channel. The annular cooling channel includes an annular input channel and an annular output channel. An air inlet is provided at the top of the annular input channel, and an air outlet is provided at the top of the annular output channel. The annular input channel and the annular output channel are interconnected from the bottom of the suspension cylinder.

[0015] The present invention also provides a storage medium storing a computer program, which when executed by a processor, implements the steps of the above-mentioned double-shaft lime kiln suspension cylinder temperature monitoring method.

[0016] The present invention has the following beneficial effects:

[0017] In the double-shaft lime kiln suspension cylinder temperature monitoring method of the present invention, by obtaining the air temperature t of each temperature measurement point i , the average temperature rise a of the temperature measurement interval j is obtained through the formula j ; finally, according to the relative relationship between the average temperature rise a j and the average temperature rise curve, find the average temperature rise a on the average temperature rise curve that deviates more than the preset threshold j to determine the local over-temperature area; the present invention adopts the heat transfer law between the air flow (cooling air flow) and the wall surface, uses the mean value screening method and the change of the average temperature rise to make the abnormal temperature rise change significantly, determines the local over-temperature area, can accurately measure the average temperature of the suspension cylinder, and captures the local temperature over-temperature of the suspension cylinder, is more sensitive to the capture and monitoring of the local over-temperature of the suspension cylinder, can provide timely early warning for the production site, and thus effectively extends the operation life of the suspension cylinder.

[0018] In addition to the purposes, features and advantages described above, the present invention has other purposes, features and advantages. The following will refer to the drawings to further elaborate on the present invention in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0020] Figure 1 is the flow chart of the double-shaft lime kiln suspension cylinder temperature monitoring method in an embodiment of the present invention;

[0021] Figure 2 is the schematic flow chart of step S3 in an embodiment of the present invention;

[0022] Figure 3 is the flow chart of the double-shaft lime kiln suspension cylinder temperature monitoring method in another embodiment of the present invention;

[0023] Figure 4 is one of the structural schematic diagrams of the suspension cylinder for the double-shaft lime kiln in the present invention;

[0024] Figure 5 is the second structural schematic diagram of the suspension cylinder for the double-shaft lime kiln in the present invention;

[0025] Figure 6 is one of the schematic diagrams of the principle of a specific monitoring example in the present invention;

[0026] Figure 7 It is the second schematic diagram of the principle of a specific monitoring example in the present invention;

[0027] Figure 8 It is the third schematic diagram of the principle of a specific monitoring example in the present invention.

[0028] Legend description:

[0029] 100, suspension cylinder; 10, outer shell; 20, inner shell; 30, annular air flow channel; 31, intake channel; 32, exhaust channel; 40, intermediate partition; 50, spiral-in spiral fin; 60, spiral-out spiral fin; 70, temperature sensor; 80, intake pipe; 90, exhaust pipe. Specific embodiments

[0030] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0032] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0033] In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] Such as Figure 1 , Figure 2 and Figure 3As shown in the figure, a method for monitoring the temperature of the suspension cylinder of a double-shaft lime kiln provided by the present invention. There are multiple temperature measurement points in the air-cooling flow channel of the suspension cylinder, and the streamline lengths between adjacent two of the temperature measurement points are the same. Define i as the temperature measurement point number, i ∈ [0, N], and number the temperature measurement points in sequence along the air flow direction in the air-cooling flow channel. 0 represents the number of the first temperature measurement point, and N represents the number of the last temperature measurement point. Define that N + 1 temperature measurement points divide the air-cooling flow channel into N temperature measurement intervals j, j = i + 1, j ∈ [1, N], j is the temperature measurement interval number, and the temperature measurement interval number between temperature measurement point i and temperature measurement point i + 1 is j. The method includes the following steps: S1. Obtain the air temperature t of each temperature measurement point i in the air-cooling flow channel of the suspension cylinder i ; S2. Use the formula a j = t i+1 - t i , to obtain the average temperature rise a j of the temperature measurement interval j; According to the average temperature rise curve corresponding to the average temperature rise a j , determine that the average temperature rise a j deviating greater than the preset threshold on the average temperature rise curve is an abnormal temperature rise, and obtain the area corresponding to the abnormal temperature rise as the over-temperature area. Specifically, the temperature measurement interval j represents the area between temperature measurement point i and temperature measurement point i + 1. For example, the temperature measurement interval numbered 5 represents the area between the temperature measurement point numbered 4 and the temperature measurement point numbered 5

[0035] The method for monitoring the temperature of the suspension cylinder of the double-shaft lime kiln provided by the present invention, by obtaining the air temperature t of each temperature measurement point i , obtaining the average temperature rise a j of the temperature measurement interval j through the formula; Finally, according to the relative relationship between the average temperature rise a j and the average temperature rise curve, find the average temperature rise a j deviating greater than the preset threshold on the average temperature rise curve to determine the local over-temperature area; The present invention adopts the heat transfer law between the air flow (cooling air flow) and the wall surface, uses the mean value screening method and the change of the average temperature rise to make the abnormal temperature rise show obvious changes, determines the local over-temperature area, can accurately measure the average temperature of the suspension cylinder, and captures the local temperature over-temperature of the suspension cylinder. The capture and monitoring of the local temperature over-temperature of the suspension cylinder are more sensitive, can provide timely early warning for the production site, and thus effectively extend the operation life of the suspension cylinder

[0036] It can be understood that, through the formula, obtain the average temperature rise a j of each temperature measurement interval j, and find the average temperature rise a j deviating greater than the preset threshold on the average temperature rise curve to determine the local over-temperature area

[0037] It can be understood that in the present invention, a total of N+1 temperature sensors are provided, and the multiple temperature sensors are arranged along the airflow direction in the airflow cooling channel, and the temperature measurement points are numbered in sequence with a natural number i, i∈[0, N], t i represents the temperature value obtained by the temperature sensor numbered i. Obviously, t 0 is the temperature measured by the temperature sensor numbered 0, that is, the wind temperature at the temperature measuring point at the air inlet of the air flow cooling channel, t N It is the temperature measured by the temperature sensor numbered N, that is, the wind temperature at the temperature measuring point at the exhaust outlet of the airflow cooling channel.

[0038] Furthermore, the method further comprises step S31, using the formula The estimated average wall temperature T′ of the suspension cylinder is calculated w , where T′ w represents the estimated average wall temperature, t 0 represents the wind temperature at the temperature measuring point at the air inlet of the air flow cooling channel, t N represents the wind temperature at the exhaust outlet of the air cooling channel, h is the heat transfer coefficient between the cooling airflow and the wall, A is the total heat transfer area, m is the air flow rate of the cooling airflow, c p The present invention adopts derivation and design to measure the temperature at the monitoring point and calculate the overall temperature of the suspension cylinder.

[0039] It can be understood that, in a specific implementation, i represents the number of the temperature measuring point (temperature detector), t i It is represented by the wind temperature corresponding to the temperature measuring point, j (j=i+1) represents the temperature measuring interval number between the temperature measuring point i and the temperature measuring point i+1, a j (i.e. a i+1 ) represents the average temperature rise of the temperature measurement interval numbered j, that is, the average temperature rise between the temperature measurement point numbered i and the temperature measurement point numbered i+1. Specifically, if the average temperature rise a 5 It is an abnormal temperature rise. The over-temperature area corresponding to the abnormal temperature rise is the streamline area between the temperature measuring point numbered 4 and the temperature measuring point numbered 5.

[0040] It can be understood that the average temperature rise a can be j The first fitting linear line (i.e., the average temperature rise curve) is obtained by linear fitting of the series of y 1 =c 1 ·x 1 +b 1 .

[0041] Furthermore, the method further comprises step S32, using the formula Calculate the corrected average wall temperature T″ w, where the corrected wall average temperature is the actual average wall temperature, and Δx is the streamline length of the temperature measurement interval. Optionally, Δx is the streamline length from the starting point to the end point of the temperature measurement interval.

[0042] Further, the step S2 specifically includes: S21, using the formula a j =t i+1 -t i , to obtain the average temperature rise a j of the temperature measurement interval j; S22, performing linear fitting on the sequence of the average temperature rise a j to obtain the first fitting linear line, y 1 =c 1 ·x 1 +b 1 ; S23, obtaining the fitting projection distance d j corresponding to each of the average temperature rises a j on the first fitting linear line; S24, obtaining the average projection value d′ according to the fitting projection distance d j ; S25, using a preset formula to obtain the average temperature rise a j corresponding to the preset formula from each of the average temperature rises a j as the abnormal temperature rise, where the range value of the first threshold k 1 is 1.5 to 3; S26, determining the area corresponding to the abnormal temperature rise as the over-temperature area. It can be understood that a j is a i+1 , and k 1 is a set troubleshooting threshold greater than 1. The larger the value of k 1 , the smaller the sensitivity, but the smaller the misjudgment probability; the smaller the value of k 1 , the greater the sensitivity, but the greater the misjudgment probability. In the present invention, the range value of k 1 is obtained according to actual on-site tests and is 1.5 to 3. In specific implementation, if the value of d j satisfies , it indicates that there is local over-temperature between the temperature measurement point numbered i and the temperature measurement point numbered i + 1.

[0043] It can be understood that y 1 refers to the average temperature rise of the temperature measurement interval, x 1 is the streamline length from the starting point to the end point of the temperature measurement interval, c 1 is the slope of the straight line, and b 1 is the intercept of the straight line.

[0044] It can be understood that in the present invention, the abnormal temperature rise can also be determined by the slope of the connection line between two adjacent average temperature rises a j . If the slope of the connection line between two adjacent average temperature rises a jIf the absolute value of the slope is greater than the preset slope value, the corresponding average temperature rise a at the rear is determined j as an abnormal temperature rise.

[0045] Please refer to Figure 3 , further, it further includes step S4, after removing all the abnormal temperature rises from each of the average temperature rises a j , a second fitted linear line y 2 = c 2 ·x 2 + b 2 is obtained by linear fitting.

[0046] Further, it further includes S5, and the local temperature T corresponding to each of the abnormal temperature rises is calculated by using the formula wc (i + 1), where Δx is the streamline length of a single temperature measurement interval. By adopting the above method, the over-temperature corresponding to the local abnormal temperature rise can be accurately calculated, which is convenient for maintenance and improves the service life of the suspension cylinder.

[0047] Further, the average projection value d′ is calculated by using the formula .

[0048] Please refer to Figure 4 and Figure 5 , the present invention also provides a temperature monitoring system for a double-chamber lime kiln suspension cylinder, including a temperature sensor and a suspension cylinder with an air-cooling flow channel, the temperature sensors are arranged in one-to-one correspondence with the temperature measurement points, the temperature sensors are used to monitor the temperature of the corresponding temperature measurement points, a plurality of temperature sensors are arranged at intervals along the extension direction of the air-cooling flow channel, the streamline length between two adjacent temperature sensors is the same, and it further includes a calculator device, the calculator device includes a memory, a processor, and a computer program stored in the memory and operable on the processor, and when the processor executes the computer program, the above-mentioned temperature monitoring method for the double-chamber lime kiln suspension cylinder based on wet capacity performance is realized.

[0049] Further, the air-cooling flow channel adopts a spiral cooling channel, the spiral cooling channel includes a spiral inlet channel and a spiral outlet channel, an air inlet is arranged at the top of the spiral inlet channel, an air outlet is arranged at the top of the spiral outlet channel, and the spiral inlet channel and the spiral outlet channel are communicated with each other from the bottom of the suspension cylinder.

[0050] Further, the air-cooling flow channel adopts an annular cooling channel, the annular cooling channel includes an annular input channel and an annular output channel, an air inlet is arranged at the top of the annular input channel, an air outlet is arranged at the top of the annular output channel, and the annular input channel and the annular output channel are communicated with each other from the bottom of the suspension cylinder.

[0051] Please refer to again Figure 5 andFigure 6 , optionally, the specific structure of the double-shaft lime kiln suspension cylinder temperature monitoring system is as follows: It includes a suspension cylinder 100 with an annular air flow channel. The suspension cylinder 100 includes an outer shell 10 and an inner shell 20. The outer shell 10 surrounds the inner shell 20 to form an annular air flow channel 30. It also includes an intermediate partition 40, a spiral-in spiral blade 50, and a spiral-out spiral blade 60. The intermediate partition 40 is arranged between the outer shell 10 and the inner shell 20 to divide the annular air flow channel 30 into an intake channel 31 and an exhaust channel 32. The spiral-in spiral blade 50 is arranged in the intake channel 31 to form a spiral-in channel in the intake channel 31. The spiral-out spiral blade 60 is arranged in the exhaust channel 32 to form a spiral-out channel in the exhaust channel 32. The intake end of the spiral-in channel is provided with an intake inlet, and the exhaust end of the spiral-out channel is provided with an exhaust outlet. The exhaust end of the spiral-in channel is communicated with the intake end of the spiral-out channel to form a spiral cooling channel.

[0052] It can be understood that in the present invention, both the outer shell 10 and the inner shell 20 are made of steel structure. The intermediate partition 40, the spiral-in spiral blade 50, and the spiral-out spiral blade 60 can be made of steel structure. The spiral-in spiral blade 50 is arranged circumferentially around the suspension cylinder 100 and extends axially towards the bottom of the suspension cylinder 100 to introduce cooling air flow. The spiral-out spiral blade 60 is arranged circumferentially around the suspension cylinder 100 and extends axially towards the top of the suspension cylinder 100 to discharge the cooling air flow.

[0053] Optionally, the spiral-in spiral blade 50 is spirally inserted around the inner shell 20 and arranged between the intermediate partition 40 and the inner shell 20 to form a spiral-in channel in the intake channel 31. The spiral-out spiral blade 60 is spirally out around the intermediate partition 40 and arranged between the intermediate partition 40 and the outer shell 10 to form a spiral-out channel in the exhaust channel 32. It can be understood that since the temperature inside the suspension cylinder 100 is higher than that outside, in order to facilitate reducing the temperature of the inner shell 20, the spiral-in channel is arranged close to the inner shell 20.

[0054] Optionally, the spiral-in spiral blade 50 is spirally inserted around the inner shell 20 and arranged between the intermediate partition 40 and the inner shell 20 to form a spiral-in channel in the intake channel 31. The spiral-out spiral blade 60 is spirally out around the intermediate partition 40 and arranged between the intermediate partition 40 and the outer shell 10 to form a spiral-out channel in the exhaust channel 32.

[0055] Optionally, the air inlet is provided at the top of the suspension cylinder 100, the exhaust outlet is provided at the top of the suspension cylinder 100, a first ventilation hole is provided at the bottom of the spiral-in spiral fin 50, a second ventilation hole is provided at the bottom of the spiral-out spiral fin 60, and by providing the first ventilation hole and the second ventilation hole, the spiral-in channel and the spiral-out channel are communicated from the bottom of the suspension cylinder 100, so that the spiral-in channel and the spiral-out channel are combined to form a spiral cooling channel.

[0056] Optionally, it further includes an intake duct 80 provided outside the suspension cylinder 100 and communicated with the air inlet, and an exhaust duct 90 provided outside the suspension cylinder 100 and communicated with the exhaust outlet. Thus, it is convenient to introduce the cooling air flow into the spiral-in channel from above the suspension cylinder 100 through the intake duct 80, and lead out the cooled cooling air flow from above the suspension cylinder 100.

[0057] Optionally, in order to facilitate detecting the temperature of the spiral cooling channel and avoid local overheating, temperature sensors 70 are provided in the spiral cooling channel. Optionally, the temperature sensors 70 are thermocouples.

[0058] Optionally, the temperature sensors 70 are arranged at equal streamline length intervals along the air flow direction.

[0059] It can be understood that during cooling, the cooling air flow is sent into the spiral-in channel from the air inlet end of the spiral-in channel. The cooling air flow flows through the spiral-in channel to cool the housing on one side of the spiral-in channel; then the cooling air flow continues to flow and enters the air inlet end of the spiral-out channel from the air outlet end of the spiral-in channel. The cooling air flow flows through the spiral-out channel to cool the housing on one side of the spiral-out channel, and finally flows out from the exhaust outlet of the spiral-out channel; for the ring-cooling suspension cylinder of the double-shaft lime kiln of the present invention, since the cooling air flow channel is arranged in a spiral shape that fits the wall body, the change of the streamline direction of the cooling air flow is slower and smoother, avoiding the vertical or sharp flow channel bends in the prior art. Therefore, the flow of the cooling air flow is smoother, and the pressure drop of the cooling air flow entering and leaving the annular air flow channel is significantly reduced compared with the prior art. At the same time, since the spiral air flow channel is designed to avoid small included angles in the flow channel, there is almost no flow field dead zone in the whole flow channel, which can effectively avoid local overheating caused by the flow field dead zone. The cooling air flow has less flow resistance during the cooling process and has a good cooling effect.

[0060] Through research, it is found that the existing technology for temperature monitoring of the suspension cylinder is to set several thermocouple thermometers at local positions of the suspension cylinder block, and monitor and give early warnings by directly capturing temperature anomalies at the measurement points. This method can only capture temperature overlimits at the measurement point position and its vicinity or overall temperature overlimits, and is not sensitive enough to temperature changes at positions a certain distance from the measurement point. When local overheating occurs in areas outside the vicinity of the temperature measurement point, the temperature at the temperature measurement point often does not change significantly. Therefore, it is impossible to accurately monitor and give timely warnings about local overheating in areas outside the temperature measurement point. In the present invention, a temperature monitoring method for the suspension cylinder based on mean screening is adopted. By calculating the average temperature rise in the temperature measurement interval for linear change, local overheating can be effectively captured, the sensitivity of the temperature measurement system to local overheating can be improved, timely warnings can be provided for the production site, and the operating life of the suspension cylinder can be effectively extended.

[0061] The present invention also provides a storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the above-mentioned temperature monitoring method for the suspension cylinder of the double-shaft lime kiln are implemented.

[0062] The theoretical basis of the temperature monitoring method of the present invention is as follows:

[0063] First, the functional relationship between the wall temperature and the air temperature is found through research: When the lime kiln is operating, the material temperature generally remains at 1100 °C. The temperature of the material is conducted through the refractory layer and the heat insulation layer to the steel shell of the suspension cylinder, and the temperature is generally below 500 °C. Since the material temperature field at the annular channel is relatively uniform, it can be approximately considered that when there is no local damage, the temperatures at all parts of the suspension cylinder shell are basically uniform, and it is represented by T'. w The heat transfer process of the fluid flowing through the constant-temperature wall surface can be described by the following formula:

[0064] h·C·dx·(T w -t x )=m·c p ·dt x ,

[0065] That is:

[0066]

[0067] After integrating both sides of the above formula, we have:

[0068]

[0069] In the formula, h is the heat transfer coefficient between the gas and the wall surface, which is basically equal at all parts of the suspension cylinder shell; C is the contact boundary length between the gas and the shell, Δx is the streamline length (integration step) of the temperature measurement interval, C×Δx = A is the contact area; m is the air flow rate; cp is the specific heat of the air. Through the above formula, the formula for predicting the average wall temperature can be derived:

[0070]

[0071] Wherein, t 0 and t N are the inlet air temperature and the outlet air temperature respectively, and A is the total heat transfer area, i.e., the area of the hanging cylinder shell.

[0072] From Equation (1), the calculation formula for the air temperature at any point can be deduced

[0073] Next, study the influence relationship of local overheating on the air temperature, and define the average temperature rise a of the monitoring point j (i.e., a i+1 ),

[0074] a i+1 = t i+1 - t i (2)

[0075] Substitute t x into the calculation formula, and we get:

[0076]

[0077] In actual production, and otherwise it will cause the outlet air temperature to be too high. Therefore, a j can be estimated by the following formula:

[0078]

[0079] After arrangement, we have:

[0080]

[0081] That is: in the case of non-abnormal temperature rise a j the distribution is approximately linear, while at the abnormal temperature rise, a j will have obvious differences. Therefore, by linearly fitting a j , the first fitting linear line y 1 = c 1 ·x 1 + b 1 can be obtained. The points that deviate significantly from the first fitting linear line are the abnormal temperature rises. Among them:

[0082]

[0083] The following mean value screening method can be used to determine whether a point is a significantly deviated point: calculate the projection distance d j between the average temperature rise a j and the first fitting linear line, and then calculate d jThe average value d′. Since the number of abnormal temperature rises is generally much smaller than the number of temperature measurement points, the average value d′ will be closer to the projection distance between the normal point and the first fitting linear line, while the abnormal temperature rise d i value is much larger than the average value d′. Therefore, the following formula can be used to detect abnormal temperature rises:

[0084]

[0085] Secondly, study the correction method of the estimated average wall temperature T′ w . Due to local overheating or estimation error of the wall heat transfer coefficient h, when calculating the estimated average wall temperature T′ w using Equation (1), an estimation error will occur. According to the slope c 2 of the straight line and the intercept b 2 and their relationship with the wall temperature, the following calculation formula can be obtained:

[0086]

[0087] Finally, study the calculation method of the local overheating value T wc :

[0088] Using the expression of a j between (i, i + 1) near the local abnormal temperature rise, we have:

[0089]

[0090] Substituting c 2 and b 2 into the calculation formula, the following calculation formula for the local overheating T wc can be obtained:

[0091]

[0092] Please refer to Figure 6 , Figure 7 and Figure 8 for a specific monitoring example: In this example, the actual average wall temperature is 600 °C, the cold fluid inlet temperature is 25 °C, the cold fluid outlet temperature is 250 °C, and a total of 41 temperature measurement points are set. Among them, there is local high temperature between the temperature measurement points numbered 8 - 9, 16 - 17, 24 - 25, and 32 - 33, with a value of 650 °C. The value of T w estimated by Equation (1) is 650 °C. Then the actual values and average temperature rise values of the measured temperatures at each point are as follows. Figure 7The measured temperature values at each point obtained from the measurement are given respectively, along with the curve corresponding to the average temperature rise value. As can be seen from the figure, the local abnormal temperature rise cannot be clearly reflected as abnormal on the measured temperature curve, but on the average temperature rise curve, it can be clearly seen that at the abnormal temperature rise, the value of the curve deviates significantly from other normal values. The average value of the abnormal temperature rise is significantly farther away from the linear fitting curve, so it can be relatively easily found by using the method of mean value screening.

[0093] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for monitoring the temperature of the suspension cylinder of a double-chamber lime kiln, characterized in that, a plurality of temperature measurement points are provided in the air flow cooling channel of the suspension cylinder, and the streamline lengths between adjacent two of the temperature measurement points are the same. Define i as the temperature measurement point number, i ∈ [0, N], and the temperature measurement points are numbered in sequence along the air flow direction in the air flow cooling channel. 0 represents the number of the first temperature measurement point, and N represents the number of the last temperature measurement point; it is defined that N + 1 temperature measurement points divide the air flow cooling channel into N temperature measurement intervals j, j = i + 1, j ∈ [1, N], j is the temperature measurement interval number, and the temperature measurement interval number between temperature measurement point i and temperature measurement point i + 1 is j, including the following steps: S1, obtain the air temperature of each temperature measurement point i in the air-cooling flow channel of the suspension cylinder ; S2, use the formula to obtain the average temperature rise in the temperature measurement interval j ; According to the average temperature rise corresponding to the average temperature rise curve, determine the average temperature rise on the average temperature rise curve that deviates more than the preset threshold as the abnormal temperature rise, and obtain the area corresponding to the abnormal temperature rise as the over-temperature area. It also includes the steps: S31, use the formula to calculate the estimated average wall temperature of the suspension cylinder , where represents the estimated average wall temperature, represents the air temperature at the temperature measurement point at the air inlet of the air-cooling flow channel, represents the air temperature at the temperature measurement point at the exhaust outlet of the air-cooling flow channel, h is the heat transfer coefficient between the cooling air flow and the wall surface, A is the total heat transfer area, m is the air flow rate of the cooling air flow, is the specific heat of air.

2. The method for monitoring the temperature of the suspension cylinder of a double-chamber lime kiln according to claim 1, characterized in that, the step S2 specifically includes: S21, use the formula , to obtain the average temperature rise in the temperature measurement interval j ; S22, for the average temperature rise of the sequence of numbers, perform linear fitting to obtain the first fitted linear line, , which refers to the average temperature rise in the temperature measurement interval, which is the streamline length from the starting point to the ending point of the temperature measurement interval, which is the slope of the straight line, which is the intercept of the straight line; S23, obtain each of the average temperature rises The fitting projection distance corresponding to the first fitting linear line ; S24. Obtain the average projection value according to the fitted projection distance Obtain the average projection value ; S25, using a preset formula , from each of the average temperature rises to obtain the average temperature rise corresponding to the preset formula as an abnormal temperature rise, where the range value of the first threshold is from 1.5 to 3; S26, determining the area corresponding to the abnormal temperature rise as the over-temperature area.

3. The method for monitoring the temperature of the suspension cylinder of a double-chamber lime kiln according to claim 2, characterized in that, it also includes the steps: S4. After excluding all the abnormal temperature rises from each of the average temperature rises, perform linear fitting to obtain a second fitting linear line. where is the relative temperature rise after excluding all the abnormal temperature rises, is the streamline length from the starting point to the ending point of the temperature measurement range after excluding all the abnormal temperature rises, is the straight-line slope, and is the straight-line intercept.

4. The method for monitoring the temperature of the suspension cylinder of a double-chamber lime kiln according to claim 3, characterized in that, it also includes the steps: S32, use the formula to calculate the corrected wall average temperature , where the corrected wall average temperature is the actual average wall temperature, and is the streamline length of the temperature measurement interval, and / or steps: S5, using the formula , calculate the local temperature corresponding to each of the abnormal temperature rises , where is the streamline length of the temperature measurement interval, represents the average temperature rise of the temperature measurement interval numbered j.

5. A temperature monitoring system for the suspension cylinder of a double-chamber lime kiln, characterized in that, it includes a temperature sensor and a suspension cylinder with an air flow cooling channel. The temperature sensors are arranged in one-to-one correspondence with the temperature measurement points. The temperature sensors are used to monitor the temperature of the corresponding temperature measurement points. A plurality of the temperature sensors are arranged at intervals along the extension direction of the air flow cooling channel, and the streamline lengths between adjacent two of the temperature sensors are the same, and it also includes a calculator device. The calculator device includes a memory, a processor, and a computer program stored in the memory and operable on the processor. When the processor executes the computer program, it implements the method for monitoring the temperature of the suspension cylinder of a double-chamber lime kiln according to any one of claims 1 to 4.

6. The temperature monitoring system for the suspension cylinder of a double-chamber lime kiln according to claim 5, characterized in that, the air flow cooling channel adopts a spiral cooling channel. The spiral cooling channel includes a spiral inlet channel and a spiral outlet channel. An air inlet is provided at the top of the spiral inlet channel, and an air outlet is provided at the top of the spiral outlet channel. The spiral inlet channel and the spiral outlet channel are interconnected from the bottom of the suspension cylinder.

7. The temperature monitoring system for the suspension cylinder of a double-chamber lime kiln according to claim 6, characterized in that, the air flow cooling channel adopts an annular cooling channel. The annular cooling channel includes an annular input channel and an annular output channel. An air inlet is provided at the top of the annular input channel, and an air outlet is provided at the top of the annular output channel. The annular input channel and the annular output channel are interconnected from the bottom of the suspension cylinder.

8. A storage medium, the storage medium stores a computer program, characterized in that, when the computer program is executed by a processor, it implements the steps of the method for monitoring the temperature of the suspension cylinder of a double-chamber lime kiln according to any one of claims 1 to 4.

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