A method for controlling the temperature of the flue gases of a gas-fired boiler

Abstract

The present application relates to gas boiler technical field, propose a kind of gas boiler furnace gas temperature control method, comprising: in the process of preparing lubricating oil, gas boiler infrared image is collected, obtain gas boiler binary image, mark hot spot, cold spot, obtain short run, determine the hot and cold spot intersection factor of gas boiler infrared image;Divide growth area, determine local temperature feature point and category, obtain the local temperature difference factor of target local temperature feature point, and then obtain the material influence factor of gas boiler infrared image;According to the material influence factor of gas boiler infrared image, determine the target temperature of gas boiler infrared image, the target temperature of gas boiler infrared image is used as the heating temperature of gas boiler, realize the control of gas boiler furnace gas temperature.The present application aims to solve the problem that the collected real-time temperature in furnace cannot reflect the real temperature in furnace, leading to unreasonable gas boiler furnace gas temperature control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas-fired boilers, in particular to a gas-fired boiler flue gas temperature control method. BACKGROUND

[0002] Traditional flue gas temperature control relies on thermocouple measurement of flue gas temperature. The thermocouple is directly inserted into the furnace to collect real-time temperature, and the flue gas temperature of the gas-fired boiler in the lubricating oil preparation process is controlled according to the real-time temperature collected in the furnace. However, in the process of preparing lubricating oil, due to the influence of factors such as quality difference of lubricating oil raw materials, raw material sedimentation, poor flowability of lubricating oil raw materials, which will accumulate in the furnace, resulting in uneven heat distribution in the furnace, the real-time temperature collected cannot reflect the real temperature in the furnace, resulting in unreasonable control of the flue gas temperature of the gas-fired boiler. SUMMARY

[0003] The present application provides a gas-fired boiler flue gas temperature control method to solve the problem that the collected real-time temperature in the furnace cannot reflect the real temperature in the furnace, resulting in unreasonable control of the flue gas temperature of the gas-fired boiler. The technical solution adopted is as follows:

[0004] An embodiment of the present application provides a gas-fired boiler flue gas temperature control method, which comprises the following steps:

[0005] Collecting a gas-fired boiler infrared image during the preparation of lubricating oil;

[0006] Binarizing the gas-fired boiler infrared image to obtain a gas-fired boiler binary image, marking hot spots and cold spots in the gas-fired boiler binary image according to the pixel value of the pixel points and the position distribution of the pixel points in the gas-fired boiler binary image, determining the hot and cold spot intersection factor of the gas-fired boiler infrared image according to the difference between the number of hot spots and the number of cold spots in the gas-fired boiler binary image, and the distribution of continuously appearing hot spots and continuously appearing cold spots;

[0007] According to the position distribution of the hot spots and cold spots in the gas-fired boiler binary image, and the infrared thermal radiation value of the hot spots and cold spots, dividing the growth region, determining the local temperature feature point and the type of the local temperature feature point according to the corresponding infrared thermal radiation value of the pixel points contained in the growth region in the gas-fired boiler infrared image, taking any one local temperature feature point as a target local temperature feature point, obtaining the local temperature difference factor of the target local temperature feature point according to the distance between all types of local temperature feature points and the growth region where the local temperature feature point is located, and combining the hot and cold spot intersection factor of the gas-fired boiler infrared image to obtain the material influence factor of the gas-fired boiler infrared image;

[0008] According to the material influence factor of the gas boiler infrared image, the target temperature of the gas boiler infrared image is determined, the target temperature of the gas boiler infrared image is taken as the heating temperature of the gas boiler, and the control of the gas boiler furnace gas temperature is realized.

[0009] Further, the gas boiler infrared image is binarized to obtain a gas boiler binary image, hot spots and cold spots in the gas boiler binary image are marked according to pixel value of the pixel points in the gas boiler binary image and position distribution of the pixel points, and the specific method comprises the following steps:

[0010] The gray value of the pixel point with the pixel value greater than or equal to the division threshold in the gas boiler infrared image is recorded as 1, and the gray value of the pixel point with the pixel value less than the division threshold in the gas boiler infrared image is recorded as 0, and the gas boiler binary image is obtained;

[0011] The pixel point with the gray value of 1 in the gas boiler binary image is recorded as a hot spot, and the pixel point with the gray value of 0 in the gas boiler binary image is recorded as a cold spot.

[0012] Further, the specific method for determining the cold-hot spot intersection factor of the gas boiler infrared image according to the difference between the number of hot spots and the number of cold spots in the gas boiler binary image and the number of short runs in the gray run length matrix of the distribution of the continuously appearing hot spots and the continuously appearing cold spots comprises the following steps:

[0013] The gray run length matrix of the gas boiler binary image in the horizontal direction is calculated, the run length smaller than half of the maximum run length in the gray run length matrix is recorded as a short run, and the short run in the gray run length matrix is obtained;

[0014] The cold-hot spot intersection factor of the gas boiler infrared image is determined according to the difference between the number of hot spots and the number of cold spots in the gas boiler binary image and the number of short runs in the gray run length matrix.

[0015] Further, the specific method for obtaining the cold-hot spot intersection factor of the gas boiler infrared image comprises the following steps:

[0016] The product of the absolute value of the difference between the number of hot spots and the number of cold spots in the gas boiler binary image and the number of short runs in the gray run length matrix is recorded as the cold-hot spot intersection factor of the gas boiler infrared image.

[0017] Further, the specific method for dividing the growth region comprises the following steps:

[0018] The gas boiler infrared image is processed using the Otsu threshold algorithm to obtain the division threshold of the gas boiler infrared image, and the product of the preset growth parameter and the division threshold of the gas boiler infrared image is recorded as the growth threshold;

[0019] The hot spots in the gas boiler binary image are subjected to connected domain analysis to obtain hot spot connected domains, and region growing is performed on all the hot spot connected domains in the gas boiler binary image to obtain hot spot growing regions;

[0020] The cold spots in the gas boiler binary image are subjected to connected domain analysis to obtain cold spot connected domains, and region growing is performed on all the cold spot connected domains in the gas boiler binary image to obtain cold spot growing regions;

[0021] The hot spot growing regions and the cold spot growing regions are both recorded as growing regions;

[0022] Further, the specific method for determining the local temperature feature points and the types of the local temperature feature points comprises:

[0023] The pixel point with the maximum infrared thermal radiation value in the gas boiler infrared image corresponding to the pixel point in the hot spot growing region is recorded as a maximum hot spot, the pixel point with the minimum infrared thermal radiation value in the gas boiler infrared image corresponding to the pixel point in the cold spot growing region is recorded as a minimum cold spot, and the maximum hot spot and the minimum cold spot are both recorded as local temperature feature points;

[0024] The types of the local temperature feature points are divided into two types, namely, hot spots and cold spots.

[0025] Further, the specific method for obtaining the local temperature difference factor of the target local temperature feature point comprises:

[0026] The local temperature feature point with the minimum Euclidean distance from the target local temperature feature point and the same type is recorded as a first feature point of the target local temperature feature point, and the local temperature feature point with the minimum Euclidean distance from the target local temperature feature point and the different type is recorded as a second feature point of the target local temperature feature point;

[0027] The local temperature difference factor of the target local temperature feature point is obtained according to the distances between the first feature point and the second feature point of the target local temperature feature point and the target local temperature feature point, and the growing regions in which the first feature point and the second feature point of the target local temperature feature point are located.

[0028] Further, the specific method for obtaining the local temperature difference factor of the target local temperature feature point according to the distances between the first feature point and the second feature point of the target local temperature feature point and the target local temperature feature point, and the growing regions in which the first feature point and the second feature point of the target local temperature feature point are located comprises:

[0029]

[0030] In the formula, the local temperature difference factor of the target local temperature feature point is represented; The number of pixel points contained in the growth region in which the first feature point representing the target local temperature feature point is located; The number of pixel points contained in the growth region in which the second feature point representing the target local temperature feature point is located; The distance between the first feature point representing the target local temperature feature point and the target local temperature feature point; The distance between the second feature point representing the target local temperature feature point and the target local temperature feature point.

[0031] Further, the specific method for obtaining the material influence factor is:

[0032] The product of the maximum value of the local temperature difference factor of the local temperature feature point and the cold-hot point intersection factor of the gas-fired boiler infrared image is recorded as the material influence factor of the gas-fired boiler infrared image.

[0033] Further, the specific method for determining the target temperature of the gas-fired boiler infrared image according to the material influence factor of the gas-fired boiler infrared image includes:

[0034] The product of the normalized value of the material influence factor of the gas-fired boiler infrared image and the preset second parameter is recorded as the first product of the gas-fired boiler infrared image;

[0035] The sum of the first product of the gas-fired boiler infrared image and the preset first parameter is recorded as the target temperature of the gas-fired boiler infrared image. The beneficial effects of the present application are:

[0036] In the process of preparing lubricating oil, the present application starts from the problem of uneven heat distribution in the furnace caused by the accumulation of lubricating oil preparation raw materials in the gas boiler, according to the temperature difference of the local "hot spot" and "cold spot" positions presented in the gas boiler, the pixel points corresponding to the local "hot spot" and "cold spot" are divided, and the uneven distribution characteristics of the pixel points corresponding to the local "hot spot" area and "cold spot" area are evaluated, and the cold and hot spot intersection factor of the infrared image of the gas boiler is obtained; then, the local temperature feature points corresponding to the local "hot spot" and "cold spot" are determined, the local temperature feature points are the positions with the most extreme temperature in the gas boiler, specifically, the position with the highest temperature in the local "hot spot" area or the position with the lowest temperature in the local "cold spot" area, further, according to the distance between all kinds of local temperature feature points and the growth area where the local temperature feature points are located, the local temperature difference factor of the target local temperature feature point is obtained, the local temperature difference factor evaluates the degree of heat flow influence of the target local temperature feature point by different kinds of local temperature feature points, when the local temperature difference factor of the target local temperature feature point is larger, the distance between different kinds of local temperature feature points relative to the same kind of local temperature feature point is closer, and the heat flow influence of the local temperature feature point with different types is more obvious, at this time, the influence of the heat flow of the target local temperature feature point by different kinds of local temperature feature points is more significant; finally, according to the local temperature difference factor of the target local temperature feature point and the cold and hot spot intersection factor of the infrared image of the gas boiler, the target temperature of the infrared image of the gas boiler is determined, the target temperature of the infrared image of the gas boiler is taken as the heating temperature of the gas boiler, the control of the furnace gas temperature of the gas boiler is realized, the present application comprehensively considers the temperature of the local "hot spot" and "cold spot" positions presented in the gas boiler and the heat flow influence between different positions, determines the heating temperature of the gas boiler, solves the problem that the collected real-time temperature in the furnace cannot reflect the real temperature in the furnace, and causes unreasonable control of the furnace gas temperature of the gas boiler. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0038] Figure 1 A flow chart of a gas boiler furnace gas temperature control method provided by an embodiment of the present application;

[0039] Figure 2 A flow chart of a cold and hot spot intersection factor acquisition provided by an embodiment of the present application;

[0040] Figure 3 This is a flowchart illustrating the process of obtaining material influence factors according to an embodiment of the present invention. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] Please see Figure 1 The diagram illustrates a flowchart of a gas boiler flue gas temperature control method according to an embodiment of the present invention, which includes the following steps:

[0043] Step S001: Acquire infrared images of the gas-fired boiler during the lubricant preparation process.

[0044] A high-temperature resistant infrared thermal imager with an extended lens was installed on top of a gas-fired boiler used for lubricant preparation, and infrared images of the gas-fired boiler were acquired using the high-temperature resistant infrared thermal imager.

[0045] An infrared image of a gas-fired boiler contains the overall view inside the boiler. As an infrared image, the pixel value of each pixel in the gas-fired boiler infrared image is the infrared thermal radiation value at that pixel location.

[0046] It should be noted that, in order to facilitate image processing and denoise the infrared image of the gas boiler, this embodiment uses a bilateral filtering algorithm to denoise the infrared image of the gas boiler. In practical applications, implementers may use other existing methods such as median filtering algorithms for dimensionless processing, which are not limited here.

[0047] In this embodiment, 5 seconds is used as the acquisition time interval for the infrared image of the gas boiler. In practical applications, as other implementation methods, the implementer can decide the value of the acquisition time interval according to the actual situation. This application does not impose any special restrictions.

[0048] At this point, the infrared image of the gas-fired boiler has been obtained.

[0049] Step S002: Binarize the infrared image of the gas boiler to obtain a binary image of the gas boiler. Based on the pixel values ​​and positional distribution of the pixels in the binary image of the gas boiler, mark the hot spots and cold spots in the binary image of the gas boiler. Based on the difference between the number of hot spots and the number of cold spots in the binary image of the gas boiler, as well as the distribution of consecutive hot spots and consecutive cold spots, determine the hot-cold-cold cross factor of the infrared image of the gas boiler.

[0050] In the process of preparing lubricating oil, due to the poor flowability of the lubricating oil preparation raw materials, the accumulation of the lubricating oil preparation raw materials in the gas boiler, and the uneven distribution of heat in the gas boiler, local "hot spots" and "cold spots" appear in the gas boiler. First, the local "hot spots" and "cold spots" in the gas boiler are divided.

[0051] The gas boiler infrared image is processed using the Otsu threshold algorithm to obtain the division threshold of the gas boiler infrared image. The gray value of the pixel point with a pixel value greater than or equal to the division threshold is recorded as 1, and the gray value of the pixel point with a pixel value less than the division threshold is recorded as 0 to obtain the gas boiler binary image.

[0052] In the gas boiler binary image, the pixel point with a gray value of 1 is in the local "hot spot" area in the furnace, and the pixel point with a gray value of 0 is in the local "cold spot" area in the furnace.

[0053] The pixel point with a gray value of 1 in the gas boiler binary image is recorded as a hot spot, and the pixel point with a gray value of 0 in the gas boiler binary image is recorded as a cold spot.

[0054] When the difference between the number of hot spots and cold spots in the gas boiler binary image is greater, the uneven distribution characteristics of the pixel points in the local "hot spot" and "cold spot" areas are more obvious, and the uneven temperature change in the furnace is more intense.

[0055] The gray run length matrix of the gas boiler binary image in the horizontal direction is calculated. Since the gray value of the pixel point in the gas boiler binary image has only two values, the gray run length matrix has two rows, and the number of columns of the gray run length matrix is the maximum run length. The run length in the gray run length matrix that is less than half of the maximum run length is defined as a short run.

[0056] The calculation of the gray run length matrix and the definition of the maximum run length are both known technologies and will not be described in detail.

[0057] Specifically, the number of short runs in the gray run length matrix is used to measure the distribution of continuously appearing hot spots and cold spots. Each short run corresponds to continuously appearing hot spots or cold spots. When the short run is shorter, the length of the continuously appearing hot spots or cold spots is shorter. When the number of short runs is greater, the number of locally continuously appearing hot spots or cold spots is greater. Therefore, in the gray run length matrix, the more the number of short runs, the more obvious the cross-distribution characteristics of the pixel points in the local "hot spot" and "cold spot" areas, the higher the frequency of the alternating appearance of the local "hot spot" and "cold spot" areas in the furnace, the more intense the uneven temperature change in the furnace, and the more significant the uneven heat distribution in the furnace.

[0058] The hot and cold spot intersection factor of the gas boiler infrared image is determined according to the difference between the number of hot spots and the number of cold spots in the gas boiler binary image and the number of short runs in the gray run matrix. The hot and cold spot intersection factor of the gas boiler infrared image is positively correlated with the difference between the number of hot spots and the number of cold spots in the gas boiler binary image and the number of short runs in the gray run matrix respectively.

[0059] Preferably, as an embodiment of the present application, the product of the absolute value of the difference between the number of hot spots and the number of cold spots in the gas boiler binary image and the number of short runs in the gray run matrix is recorded as the hot and cold spot intersection factor of the gas boiler infrared image.

[0060] The calculation formula of the hot and cold spot intersection factor of the gas boiler infrared image is as follows:

[0061]

[0062] In the formula, HCF represents the hot and cold spot intersection factor of the gas boiler infrared image; Nhot represents the number of hot spots in the gas boiler binary image; Ncold represents the number of cold spots in the gas boiler binary image; and Nshort represents the number of short runs in the gray run matrix. HCF represents the hot and cold spot intersection factor of the gas boiler infrared image; Nhot represents the number of hot spots in the gas boiler binary image; Ncold represents the number of cold spots in the gas boiler binary image; Nshort represents the number of short runs in the gray run matrix.

[0063] When the difference between the number of hot spots and the number of cold spots in the gas boiler binary image is greater and the number of short runs is more, the hot and cold spot intersection factor of the gas boiler infrared image is greater, at this time, the uneven distribution characteristics of the pixel points in the local "hot spot" and "cold spot" regions are more obvious, the temperature change in the furnace is more intense, and the possibility of local overheating or local overcooling of the gas boiler is greater.

[0064] In actual application, as other embodiments, the maximum value of the number of hot spots and the number of cold spots in the gas boiler binary image is recorded as a first quantity, the minimum value of the number of hot spots and the number of cold spots in the gas boiler binary image is recorded as a second quantity, the ratio of the first quantity to the second quantity is recorded as a first ratio, and the product of the first ratio and the number of short runs in the gray run matrix is recorded as the hot and cold spot intersection factor of the gas boiler infrared image.

[0065] At this point, the hot and cold spot intersection factor of the gas boiler infrared image is obtained, and the flow chart of the hot and cold spot intersection factor acquisition is as shown in Figure 2

[0066] ​Step S003, according to the position distribution of hot spots and cold spots in the gas boiler binary image, and the infrared thermal radiation value of the hot spots and cold spots, the growth region is divided, according to the corresponding infrared thermal radiation value of the pixel points contained in the growth region in the gas boiler infrared image, the local temperature feature point and the type of local temperature feature point are determined, any one local temperature feature point is recorded as a target local temperature feature point, according to the distance between all kinds of local temperature feature points and the growth region where the local temperature feature point is located, the local temperature difference factor of the target local temperature feature point is obtained, combined with the cold and hot spot cross factor of the gas boiler infrared image, the material influence factor of the gas boiler infrared image is obtained.

[0067] The hot spots in the gas boiler binary image are subjected to connected component analysis to obtain hot spot connected components. The product of the preset growth parameter and the division threshold value of the gas boiler infrared image is recorded as the growth threshold value. The region growing is performed on all hot spot connected components in the gas boiler binary image to obtain hot spot growth regions, wherein the number of initial seed points is set to the number of hot spot connected components, the position of the initial seed point is set to be randomly selected, the neighborhood of the pixel point is set to be the eight-neighborhood, when the absolute value of the difference between the infrared thermal radiation values of two hot spots is less than the growth threshold value, the growing is continued, otherwise, the growing is stopped; the value of the preset growth parameter in this embodiment is one fourth.

[0068] At this point, the number of hot spot connected components is obtained. The number of hot spot growth regions.

[0069] The cold spots in the gas boiler binary image can be processed in the same way to obtain cold spot connected components and cold spot growth regions, and the number of cold spot growth regions is the same as the number of cold spot connected components.

[0070] The specific method for obtaining cold spot connected components and cold spot growth regions is as follows: the cold spots in the gas boiler binary image are subjected to connected component analysis to obtain cold spot connected components. The region growing is performed on all cold spot connected components in the gas boiler binary image to obtain cold spot growth regions, wherein the number of initial seed points is set to the number of cold spot connected components, the position of the initial seed point is set to be randomly selected, the neighborhood of the pixel point is set to be the eight-neighborhood, when the absolute value of the difference between the infrared thermal radiation values of two cold spots is less than the growth threshold value, the growing is continued, otherwise, the growing is stopped.

[0071] Both the hot spot growth region and the cold spot growth region are recorded as a growth region. According to the position of the pixel points contained in the growth region, all the growth regions are simultaneously divided at the same pixel point position in the gas boiler infrared image, and the growth regions in the gas boiler infrared image include the hot spot growth region and the cold spot growth region.

[0072] The pixel point with the maximum infrared thermal radiation value in the infrared image of the gas-fired boiler corresponding to the pixel point in the hot spot growth region is recorded as a maximum hot spot, and the pixel point with the minimum infrared thermal radiation value in the infrared image of the gas-fired boiler corresponding to the pixel point in the cold spot growth region is recorded as a minimum cold spot. Both the maximum hot spot and the minimum cold spot are recorded as local temperature feature points. The types of the local temperature feature points are divided into two types, i.e., hot spots and cold spots.

[0073] It can be understood that each hot spot growth region has a maximum hot spot, and each cold spot growth region has a minimum cold spot. The maximum hot spot is located at the position with the highest temperature in the hot spot growth region, and the minimum cold spot is located at the position with the lowest temperature in the cold spot growth region.

[0074] Any one of the local temperature feature points is recorded as a target local temperature feature point. In this embodiment, any one of the local temperature feature points is taken as an example for description.

[0075] The Euclidean distances between the target local temperature feature point and all other local temperature feature points are calculated. The local temperature feature point with the minimum Euclidean distance to the target local temperature feature point and the same type as the target local temperature feature point is recorded as a first feature point of the target local temperature feature point, and the local temperature feature point with the minimum Euclidean distance to the target local temperature feature point and the different type from the target local temperature feature point is recorded as a second feature point of the target local temperature feature point.

[0076] Preferably, as an embodiment of the present application, the local temperature difference factor of the target local temperature feature point is obtained according to the distances between the first feature point and the second feature point of the target local temperature feature point and the target local temperature feature point, and the growth regions in which the first feature point and the second feature point of the target local temperature feature point are located.

[0077]

[0078] In the formula, the local temperature difference factor of the target local temperature feature point is represented; the number of pixel points contained in the growth region in which the first feature point of the target local temperature feature point is located is represented; the number of pixel points contained in the growth region in which the second feature point of the target local temperature feature point is located is represented; the distance between the first feature point of the target local temperature feature point and the target local temperature feature point is represented; the distance between the second feature point of the target local temperature feature point and the target local temperature feature point is represented.

[0079] When The greater the distance between the second feature point of the target local temperature feature point and the target local temperature feature point is relative to the distance between the first feature point of the target local temperature feature point and the target local temperature feature point, that is, the more obvious the heat flow influence of the local temperature feature point different in kind from the target local temperature feature point is, and the more significant the influence of the heat flow influence of the local temperature feature point different in kind on the target local temperature feature point is.

[0080] When The greater the distance between the second feature point of the target local temperature feature point and the target local temperature feature point is relative to the distance between the first feature point of the target local temperature feature point and the target local temperature feature point, that is, the more obvious the heat flow influence of the local temperature feature point different in kind from the target local temperature feature point is, and the more significant the influence of the heat flow influence of the local temperature feature point different in kind on the target local temperature feature point is.

[0081] According to the same method, the local temperature difference factor of any local temperature feature point can be obtained, that is, for each maximum hot spot and each minimum cold spot in the hot spot growth area, there is a corresponding local temperature difference factor.

[0082] According to the values of the local temperature difference factors of all local temperature feature points and the cold-hot spot intersection factor of the gas-fired boiler infrared image, the material influence factor of the gas-fired boiler infrared image is obtained.

[0083] Preferably, as an embodiment of the present application, the product of the maximum value of the local temperature difference factor of the local temperature feature point and the cold-hot spot intersection factor of the gas-fired boiler infrared image is recorded as the material influence factor of the gas-fired boiler infrared image.

[0084] The calculation formula of the material influence factor of the gas-fired boiler infrared image is:

[0085]

[0086] In the formula, The material influence factor of the gas-fired boiler infrared image is represented by K; The cold-hot spot intersection factor of the gas-fired boiler infrared image is represented by K; The maximum value of the local temperature difference factor of the local temperature feature point is represented by Kmax.

[0087] The greater the maximum value of the local temperature difference factor of the local temperature feature point, the greater the possibility of the local temperature feature point in the gas boiler infrared image being affected by the heat flow of the local temperature feature point of a different kind, at this time, the influence between the local temperature feature point and the nearest local temperature feature point of a different kind is more significant, the non-uniform temperature change in the furnace is more severe, and the possibility of the gas boiler having a local overheating or local subcooling problem is greater. Therefore, the greater the maximum value of the local temperature difference factor of the local temperature feature point and the greater the cold-hot spot intersection factor of the gas boiler infrared image, the more significant the uneven distribution characteristics of the local "hot spot" and "cold spot" regions in the gas boiler infrared image, the more severe the non-uniform temperature change in the furnace, and the greater the possibility of the gas boiler having a local overheating or local subcooling problem.

[0088] At this point, the material influence factor of the gas boiler infrared image is obtained, and the material influence factor acquisition flowchart is as shown in Figure 3

[0089] Step S004, according to the material influence factor of the gas boiler infrared image, determining the target temperature of the gas boiler infrared image, taking the target temperature of the gas boiler infrared image as the heating temperature of the gas boiler, and realizing the control of the gas boiler furnace gas temperature.

[0090] In the preparation process of the lubricating oil, the gas boiler is used to continuously heat and keep the temperature of the oxidized vegetable oil and other additives in the range of 45-55℃, so as to ensure that the oxidized vegetable oil can better dissolve and mix other additives, improve the dissolution rate of vitamin E and tea polyphenol, and at the same time, make the subsequent added other ingredients better dissolved in the vegetable oil, wherein the subsequent added other ingredients include trimethylolpropane oleate, pour point depressant PAO-4, alkyl phosphate, sulfurized fatty acid ester and antirust agent.

[0091] This stage of keeping the temperature in the range of 45-55℃ is referred to as the temperature maintenance stage.

[0092] In the temperature maintenance stage, due to the addition of different raw materials, the gas boiler may have a local overheating or local subcooling problem, therefore, in the temperature maintenance stage, the control of the gas boiler furnace gas temperature is realized according to the material influence factor of the gas boiler infrared image, and the specific method is as follows:

[0093] According to the material influence factor of the gas boiler infrared image, the target temperature of the gas boiler infrared image is determined.

[0094] ​Preferably, as an embodiment of the present application, the product of the linear normalized value of the material influence factor of the gas boiler infrared image and the preset second parameter is recorded as the first product of the gas boiler infrared image; the sum of the first product of the gas boiler infrared image and the preset first parameter is recorded as the target temperature of the gas boiler infrared image.

[0095] The calculation formula of the target temperature of the gas boiler infrared image is as follows:

[0096]

[0097] In the formula, The target temperature of the gas boiler infrared image is represented by T; The material influence factor of the gas boiler infrared image is represented by F; The linear normalization function is represented by LN, which is used to calculate the linear normalized value of the value in the parentheses; The first parameter is represented by a, which is a preset parameter, and the value of the first parameter in the embodiment is 45; The second parameter is represented by b, which is a preset parameter, and the value of the second parameter in the embodiment is 10.

[0098] In actual application, as other embodiments, the Z-Score standard normalization method, logarithmic transformation normalization and other existing normalization methods can also be used to normalize the material influence factor of the gas boiler infrared image, and the present application does not make special limitations.

[0099] The target temperature of the gas boiler infrared image is used as the heating temperature of the gas boiler, so as to realize the control of the gas boiler furnace gas temperature.

[0100] Thus, the control of the gas boiler furnace gas temperature for the preparation of lubricating oil is realized.

[0101] The above description is only the preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement and the like made within the principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for controlling the temperature of the furnace gas of a heating furnace for the production of lubricating oil, characterized in that, The method comprises the following steps: Collecting an infrared image of a heating furnace in a lubricating oil preparation process; Collecting an infrared image of a heating furnace in a lubricating oil preparation process; Binarizing the infrared image of the heating furnace to obtain a binary image of the heating furnace, marking hot spots and cold spots in the binary image of the heating furnace according to the pixel value of the pixel points in the binary image of the heating furnace and the position distribution of the pixel points, determining a cold-hot spot intersection factor of the infrared image of the heating furnace according to the difference between the number of hot spots and the number of cold spots in the binary image of the heating furnace and the distribution of the continuously appearing hot spots and the continuously appearing cold spots; According to the position distribution of the hot spots and the cold spots in the binary image of the heating furnace and the infrared thermal radiation value of the hot spots and the cold spots, the growth region is divided, the local temperature feature points and the types of the local temperature feature points are determined according to the corresponding infrared thermal radiation value of the pixel points contained in the growth region in the infrared image of the heating furnace, any one local temperature feature point is recorded as a target local temperature feature point, the local temperature difference factor of the target local temperature feature point is obtained according to the distance between all types of local temperature feature points and the growth region where the local temperature feature point is located, and the material influence factor of the infrared image of the heating furnace is obtained in combination with the cold-hot spot intersection factor of the infrared image of the heating furnace. According to the material influence factor of the infrared image of the heating furnace, the target temperature of the infrared image of the heating furnace is determined, the target temperature of the infrared image of the heating furnace is taken as the heating temperature of the heating furnace, and the control of the furnace gas temperature of the heating furnace is realized. The method for binarizing the infrared image of the heating furnace to obtain the binary image of the heating furnace, marking the hot spots and the cold spots in the binary image of the heating furnace according to the pixel value of the pixel points in the binary image of the heating furnace and the position distribution of the pixel points comprises the following specific method: The gray value of the pixel point in the infrared image of the heating furnace with the pixel value greater than or equal to the division threshold value is recorded as 1, the gray value of the pixel point in the infrared image of the heating furnace with the pixel value less than the division threshold value is recorded as 0, and the binary image of the heating furnace is obtained; The pixel point with the gray value of 1 in the binary image of the heating furnace is recorded as a hot spot, and the pixel point with the gray value of 0 in the binary image of the heating furnace is recorded as a cold spot; The method for determining the cold-hot spot intersection factor of the infrared image of the heating furnace according to the difference between the number of hot spots and the number of cold spots in the binary image of the heating furnace and the number of short runs in the gray run matrix according to the distribution of the continuously appearing hot spots and the continuously appearing cold spots comprises the following specific method: The gray run matrix of the binary image of the heating furnace in the horizontal direction is calculated, the run with the run length less than half of the maximum run in the gray run matrix is recorded as a short run, and the short run in the gray run matrix is obtained; The cold-hot spot intersection factor of the infrared image of the heating furnace is determined according to the difference between the number of hot spots and the number of cold spots in the binary image of the heating furnace and the number of short runs in the gray run matrix; The method for dividing the growth region comprises the following specific method: The infrared image of the heating furnace is processed by using the Otsu threshold algorithm to obtain the division threshold value of the infrared image of the heating furnace, and the product of the preset growth parameter and the division threshold value of the infrared image of the heating furnace is recorded as a growth threshold value; The hot spot in the heating furnace binary image is subjected to connected domain analysis to obtain a hot spot connected domain, and region growing is performed on all hot spot connected domains in the heating furnace binary image to obtain a hot spot growth region; The cold spot in the heating furnace binary image is subjected to connected domain analysis to obtain a cold spot connected domain, and region growing is performed on all cold spot connected domains in the heating furnace binary image to obtain a cold spot growth region; Both the hot spot growth region and the cold spot growth region are recorded as a growth region; The specific method for obtaining the local temperature difference factor of the target local temperature feature point is as follows: The local temperature feature point with the minimum Euclidean distance and the same type as the target local temperature feature point is recorded as a first feature point of the target local temperature feature point, and the local temperature feature point with the minimum Euclidean distance and the different type as the target local temperature feature point is recorded as a second feature point of the target local temperature feature point; The distance between the first feature point and the second feature point of the target local temperature feature point and the target local temperature feature point, and the growth region in which the first feature point and the second feature point of the target local temperature feature point are located are used to obtain the local temperature difference factor of the target local temperature feature point.

2. A furnace gas temperature control method for a heating furnace for lubricating oil production according to claim 1, characterized by, The specific method for obtaining the cold-hot spot intersection factor of the heating furnace infrared image is as follows: The absolute value of the difference between the number of hot spots and the number of cold spots in the heating furnace binary image is multiplied by the number of short runs in the gray run matrix to obtain the cold-hot spot intersection factor of the heating furnace infrared image.

3. The furnace gas temperature control method for a heating furnace for lubricating oil production according to claim 1, characterized by, The specific method for determining the local temperature feature point and the type of the local temperature feature point is as follows: The pixel point with the maximum infrared thermal radiation value in the heating furnace infrared image in the pixel point in the hot spot growth region is recorded as a maximum hot spot, the pixel point with the minimum infrared thermal radiation value in the heating furnace infrared image in the pixel point in the cold spot growth region is recorded as a minimum cold spot, and both the maximum hot spot and the minimum cold spot are recorded as a local temperature feature point. The type of the local temperature feature point is divided into two types, namely, a hot spot and a cold spot.

4. The furnace gas temperature control method for a heating furnace for lubricating oil production according to claim 1, characterized by, The specific method for obtaining the local temperature difference factor of the target local temperature feature point according to the distance between the first feature point and the second feature point of the target local temperature feature point and the target local temperature feature point, and the growth region in which the first feature point and the second feature point of the target local temperature feature point are located is as follows: ； In the formula, c represents a local temperature difference factor of the target local temperature feature point; represents the number of pixel points contained in the growth region where the first feature point of the target local temperature feature point is located; represents the number of pixel points contained in the growth region where the second feature point of the target local temperature feature point is located; represents the distance between the first feature point of the target local temperature feature point and the target local temperature feature point; represents the distance between the second feature point of the target local temperature feature point and the target local temperature feature point.

5. The furnace gas temperature control method for a heating furnace for lubricating oil production according to claim 1, characterized by, The specific method for obtaining the material influence factor is as follows: The product of the maximum value of the local temperature difference factor of the local temperature feature point and the cold-hot spot intersection factor of the heating furnace infrared image is recorded as the material influence factor of the heating furnace infrared image.

6. The furnace gas temperature control method for a heating furnace for lubricating oil production according to claim 1, characterized by, The specific method for determining the target temperature of the heating furnace infrared image according to the material influence factor of the heating furnace infrared image is as follows: The product of the normalized value of the material influence factor of the heating furnace infrared image and a preset second parameter is recorded as a first product of the heating furnace infrared image; The sum of the first product of the heating furnace infrared image and a preset first parameter is recorded as the target temperature of the heating furnace infrared image.

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