A method and system for monitoring the uniformity of coal blending and blending combustion of a coal-fired unit

Abstract

The present application belongs to the technical field of monitoring system, and relates to a method for monitoring the uniformity of coal blending and blending combustion of a coal-fired unit, comprising: selecting initial proportions of each blending coal; monitoring the delivery amount of different coals in real time, and monitoring the uniformity of coal blending and blending combustion on a host computer, specifically from two angles of total amount monitoring and instantaneous monitoring; the instantaneous monitoring includes two modes of flow breakpoint monitoring and flow curve monitoring, the total amount monitoring is to obtain instantaneous monitoring data of each blending coal in any period of time, calculate the instantaneous flow sum of each blending coal and the proportion of each coal in the total coal amount, and obtain the actual input proportion of each blending coal; comparing the actual input proportion of each blending coal with the set initial proportion of each blending coal, if each difference value is within a predetermined threshold, it indicates that the blending is uniform; if the deviation value of a certain blending coal exceeds the predetermined threshold, it indicates that the blending is not uniform; the flow of each blending coal is predicted in real time, and if an abnormal situation occurs, timely warning is performed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of monitoring systems, and particularly relates to a method and system for monitoring the uniformity of coal blending and burning of a coal-fired unit. BACKGROUND

[0002] With the continuous rise in coal prices, coal-fired power plants have become one of the main means for enterprises to balance cost and power generation efficiency by using coal blending and burning to maximize the blending of economic coal species under the premise of ensuring stable boiler combustion. There are now methods for improving the effect of coal blending and burning through different blending methods (such as modifying the burner and optimizing the coal blending algorithm). However, there is still a lack of an effective method for monitoring and verifying the actual effect of coal blending and burning. SUMMARY

[0003] The purpose of the present application is to provide a method and system for monitoring the uniformity of coal blending and burning of a coal-fired unit, which solves the problem of lacking an effective method for monitoring and verifying the actual effect of coal blending and burning.

[0004] The present application is achieved by the following technical solutions:

[0005] A method for monitoring the uniformity of coal blending and burning of a coal-fired unit, comprising the following steps:

[0006] Step 1: Select the initial proportion of each blended coal according to the reserves and planned consumption of each type of coal in the coal bunker;

[0007] Step 2: Real-time monitor the delivery quantity of different coal species, and transmit the delivery quantity to the upper computer to monitor the uniformity of coal blending and burning on the upper computer, specifically from the perspectives of total quantity monitoring and instantaneous monitoring:

[0008] 2.1: Instantaneous monitoring includes flow breakpoint monitoring and flow curve monitoring, specifically:

[0009] Flow breakpoint monitoring: judge the uniformity of coal blending and burning by observing whether there is a flow breakpoint for each blended coal;

[0010] Flow curve monitoring: judge the uniformity of coal blending and burning by observing whether the flow curve of each blended coal is stable;

[0011] 2.2: Total quantity monitoring: obtain the instantaneous monitoring data of each blended coal in any period of time, calculate the total instantaneous flow of each blended coal and the proportion of each coal species in the total coal quantity, and then obtain the actual input proportion of each blended coal;

[0012] Compare the actual input proportion of each blended coal with the set initial proportion of each blended coal, if the difference is within the predetermined threshold range, it indicates that the blending is uniform;

[0013] If the deviation value exceeds the predetermined threshold range when comparing the actual input proportion of a certain blending coal with the corresponding set initial proportion, it indicates that the blending is uneven.

[0014] Further, in step 2.1, the uniformity of blending coal blending is judged by observing whether there is a flow breakpoint of each blending coal, specifically:

[0015] When there is a flow breakpoint, it indicates that the blending of blending coal exists uneven characteristics; when there is no flow breakpoint, it indicates that the blending of blending coal exists uniform characteristics.

[0016] Further, in step 2.1, the uniformity of blending coal blending is judged by observing whether the flow curve of each blending coal is stable, specifically: when the flow curve fluctuates, it indicates that the blending of blending coal exists uneven characteristics; when the flow curve is smooth, it indicates that the blending of blending coal exists uniform characteristics.

[0017] Further, the expression of the actual input proportion of each blending coal is a n = Q n / Q 总 × 100%; wherein, Q n is the total instantaneous flow accumulated in any period of time of a certain coal, Q 总 is the total instantaneous flow accumulated in any period of time of each coal;

[0018] The expression for comparing the actual input proportion of each blending coal with the set initial proportion of each blending coal is: Δ = |a n -a 0n |; a 0n is the initial proportion of coal n.

[0019] Further, in step 2.2, the predetermined threshold range is 5%.

[0020] The application also discloses a coal-fired unit monitoring system for the uniformity of blending coal blending, which comprises a host computer, a coal feeder, a belt conveyor and a coal bunker; the coal feeder is provided with a plurality of coal feeders for storing different types of coal; the coal feeder is connected with the coal bunker through a belt, and the belt is provided with a monitoring device for real-time monitoring of the conveying capacity of different coals; the monitoring device is connected with the host computer through a communication module, and the host computer is connected with the coal feeder for adjusting the input of each coal feeder.

[0021] The host computer is provided with an input module, a storage module, a flow breakpoint monitoring module, a flow curve monitoring module and a total amount monitoring module.

[0022] The storage module is used for the predetermined threshold range.

[0023] The input module is used for inputting the initial proportion of each blending coal.

[0024] A flow breakpoint monitoring module is configured to determine the uniformity of the blending and burning of the blended coal by observing whether there is a flow breakpoint for each blended coal;

[0025] A flow curve monitoring module is configured to determine the uniformity of the blending and burning of the blended coal by observing whether the flow curve of each blended coal is stable;

[0026] A total quantity monitoring module is configured to obtain the instantaneous monitoring data of each blended coal in any period of time, calculate the sum of the instantaneous flow of each blended coal and the proportion of each coal in the total coal quantity, and then obtain the actual input proportion of each blended coal;

[0027] The actual input proportion of each blended coal is compared with the initial proportion of each blended coal, and if the difference is within a predetermined threshold range, it indicates that the blending is uniform.

[0028] If the actual input proportion of a certain blended coal is compared with the initial proportion corresponding to the blended coal, and the deviation exceeds the predetermined threshold range, it indicates that the blending is not uniform.

[0029] Further, the host computer also has a blended coal flow prediction model configured to mine the historical flow data of each blended coal, establish a mathematical model and express the process state by using the inherent information of a large amount of data, and use a data-driven artificial neural network fault prediction technology to predict the flow of each blended coal and warn of the uniformity of the blending and burning.

[0030] Further, the monitoring device uses a flow sensor, a weight sensor or a volume sensor.

[0031] Further, the communication module uses a wired or wireless communication mode.

[0032] Further, the flow breakpoint monitoring module detects abnormal values by using LOF, Isolation Forest, K-Means clustering algorithm or One-class SVM algorithm.

[0033] Compared with the prior art, the present application has the following beneficial technical effects:

[0034] The present application discloses a system and method for monitoring the uniformity of the blending and burning of coal in a coal-fired unit, which monitors from two aspects of instantaneous monitoring and total quantity monitoring, can verify whether the set blending and burning proportion of the coal is consistent with the actual blending and burning condition, feeds back the blending and burning scheme of the coal, is beneficial to the adjustment of the blending and burning scheme of the coal in different working conditions, monitors the instantaneous blending quantity of each coal, ensures the safety and stability of the blending and burning process of the coal, scientifically guides the management of the blending and burning of the coal in the power plant for a long time, ensures the long-term safe, environmentally friendly and economic operation of the boiler equipment, and realizes the fine management of the blending and burning of the coal.

[0035] Further, by mining each blending coal historical flow data, a mathematical model and expression process state are established by using a large amount of data inherent information, a blending coal flow prediction model is established by using a data-driven artificial neural network fault prediction technology, and early warning of non-uniform blending combustion is realized. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 A monitoring flow chart of the method for monitoring uniformity of blending and combustion of blending coal of a coal-fired unit of the present application;

[0037] Figure 2 A principle diagram of the system for monitoring uniformity of blending and combustion of blending coal of the present application;

[0038] Figure 3 Flow curves of three different coals in the past period of time in a specific example.

[0039] 1, coal bunker; 2, flow sensor; 3, belt conveyor; 4, coal feeder; 5, communication module; 6, upper computer. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present application clearer and more comprehensible, the following further describes the features and performances of the present application in detail in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and are not used to limit the present application, that is, the described examples are only a part of the examples of the present application, but not all the examples.

[0041] The components described and shown in the drawings and examples of the present application can be arranged and designed in various different configurations, therefore, the detailed description of the examples of the present application provided in the following drawings is not intended to limit the scope of the claimed present application, but only to represent a selected embodiment of the present application. Based on the drawings and examples of the present application, all other examples obtained by those skilled in the art without making creative efforts are within the protection scope of the present application.

[0042] It should be noted that the terms “comprise”, “include” or other any other variant are intended to cover non-exclusive inclusion, so that the process, element, method, article or equipment including a series of elements only includes those elements, but also includes other elements not explicitly listed, or further includes the elements inherent to the process, element, method, article or equipment.

[0043] The features and performances of the present application are further described in detail in combination with the examples below.

[0044] As shown in Figure 1 The present application discloses a method for monitoring uniformity of blending and combustion of blending coal of a coal-fired unit, comprising the following steps:

[0045] The first step is to select the appropriate blending card according to the operating conditions and the reserves and planned consumption of various types of coal in the coal bunker 1. The blending card for the coal fed into the furnace is set with different types of coal and their proportions, i.e., the initial proportions of each blended coal.

[0046] The second step is to simultaneously and in real time monitor the delivery amounts of different types of coal on each coal belt conveyor 3, which are transmitted to the upper computer 6. The uniformity of the blended coal combustion can be monitored on the upper computer 6, mainly from the perspectives of total amount monitoring and instantaneous monitoring.

[0047] 2.1. The instantaneous monitoring is realized by the real-time flow data transmitted by the flow sensor 2 on the belt conveyor 3 to realize real-time observation of the delivery amounts of each blended coal.

[0048] The instantaneous monitoring includes two modes of flow breakpoint monitoring and flow curve monitoring, which are as follows:

[0049] Flow breakpoint monitoring: The uniformity of the blended coal combustion is judged by observing whether there is a flow breakpoint for each blended coal. When there is a flow breakpoint, it indicates that the blended coal combustion is not uniform; when there is no flow breakpoint, it indicates that the blended coal combustion is uniform.

[0050] Flow curve monitoring: The uniformity of the blended coal combustion is judged by observing whether the flow curve of each blended coal is stable. When the flow curve fluctuates, it indicates that the blended coal combustion is not uniform; when the flow curve is smooth, it indicates that the blended coal combustion is uniform.

[0051] 2.2. The total amount monitoring refers to selecting the instantaneous monitoring data of each blended coal in an arbitrary period of time, which can calculate the total instantaneous flow of each blended coal and the proportion of each type of coal in the total amount of coal. Thus, the actual input proportion of each blended coal can be obtained.

[0052] The value set is compared with the proportion of each blended coal set in the blending card for the coal fed into the furnace. If the difference is less than 5%, it indicates that the blending is relatively uniform. If the deviation of a certain type of coal is greater than 5%, it indicates that the blending is not uniform, and the operation and maintenance personnel will adjust the input amount of each blended coal through remote control.

[0053] Specifically, the instantaneous flow of coal 1, coal 2, and coal 3 in a period of time is accumulated to obtain all the total amount Q 总 ; the instantaneous flow of coal 1, coal 2, and coal 3 is accumulated to obtain the amounts of coal 1, coal 2, and coal 3 in this period of time, which are Q1, Q2, and Q3, respectively;

[0054] The blending proportion of coal 1 is calculated as a1 = Q1 / Q 总 × 100%; and the verification is Δ = |a1-a 01 |, where a 01 is the initial proportion of coal 1 in the blending card.

[0055] The blending ratio of coal 2 is a2 = Q2 / Q 总 ×100%; verification Δ=|a2-a 02 |, a 01 is the initial proportion of coal 1 in the blending calorie;

[0056] Similarly, the blending ratio of coal n is a n =Q n / Q 总 ×100%; verification Δ=|a n -a 0n |, a 0n is the initial proportion of coal n in the blending calorie;

[0057] like Figure 2 As shown, the present invention also discloses a system for monitoring the uniformity of coal blending and combustion of a coal-fired unit, comprising a host computer 6, a coal feeder 4, a belt conveyor 3 and a coal bunker 1; a plurality of coal feeders 4 are provided for storing different types of coal; the coal feeders 4 are connected to the coal bunker 1 via a belt, and a monitoring device is provided on the belt for real-time monitoring of the conveying amount of different types of coal; the monitoring device is connected to the host computer 6 via a communication module 5, and the host computer 6 is connected to the coal feeder 4, for adjusting the input amount of each coal feeder 4; the host computer 6 is provided with an input module, a storage module, a flow breakpoint monitoring module, a flow curve monitoring module and a total amount monitoring module;

[0058] a storage module for pre-determining a threshold range;

[0059] Input module, used to input the initial proportion of each blended coal;

[0060] The flow breakpoint monitoring module is used to determine the uniformity of coal blending by observing whether there are flow breakpoints in each blended coal;

[0061] The flow curve monitoring module is used to determine the uniformity of coal blending by observing whether the flow curve of each blended coal is stable;

[0062] The total amount monitoring module is used to obtain the instantaneous monitoring data of each blended coal in any period of time, calculate the total instantaneous flow of each blended coal and the proportion of each coal type in the total coal amount, and then obtain the actual input ratio of each blended coal;

[0063] Compare the actual input ratio of each blended coal with the set initial ratio of each blended coal. If the differences are within the predetermined threshold range, it means that the blending is uniform.

[0064] If the deviation value of the actual input ratio of a certain blended coal is compared with its corresponding set initial ratio and exceeds the predetermined threshold range, it indicates that the blending is uneven.

[0065] The monitoring device adopts a flow sensor 2, a weight sensor or a volume sensor. In addition to monitoring the instantaneous flow using the flow sensor 2 on the coal conveying belt 3, real-time monitoring can also be performed using weight monitoring or volume monitoring.

[0066] The communication module 5 can be selected from wired transmission, wireless 5G transmission and signal base station.

[0067] The function of the flow breakpoint monitoring module is to set a deviation range and directly detect abnormal values through LOF, Isolation Forest, K-Means clustering algorithm, One-class SVM and other algorithms.

[0068] Taking the K-Means clustering algorithm as an example, all objects are divided into K classes by the K-Means clustering algorithm, and it is assumed that there is a "center point" in each class, i.e. an opinion leader who is the core of the class. At this time, if a new object needs to be classified, only the distance between the point and the K center points needs to be calculated, and the one that is close to the center point belongs to that class. Thus, the flow breakpoint category and the flow deviation category are divided.

[0069] More preferably, the upper computer further comprises a blended coal flow prediction model, which is used to mine historical flow data of each blended coal, establish a mathematical model and express the process state by using the inherent information of a large amount of data, and realize prediction of the flow of each blended coal and early warning of blending uniformity by using a data-driven artificial neural network fault prediction technology.

[0070] The present application can verify whether the set blending coal blending ratio is consistent with the actual blending condition, and feedback the blending coal blending scheme, which is beneficial to the adjustment of the blending coal blending scheme setting in different working conditions. At the same time, the instantaneous blending amount of each coal is monitored to ensure the safety and stability of the blending coal blending process. The present application can long-term and scientifically guide the power plant blending coal blending management work, ensure the long-term safety, environmental protection and economic operation of the boiler equipment, and realize the fine management of blending coal blending.

[0071] The following is a specific application example:

[0072] 1. The real-time system is used to view the bin position value of any coal bin 1 and view the bin replenishment condition.

[0073] 2. The bin replenishment curve is consulted to obtain the flow curves of three different coals in the past period, as shown in Figure 3 The x-axis is time, and the y-axis is flow size.

[0074] 3. The previous blending ratio is viewed: coal 1 is 60%, coal 2 is 30%, and coal 3 is 10%.

[0075] 4. Real-time analysis of blending according to the data measured by flow sensor 2 and curve trend;

[0076] 5. Calculate the total instantaneous flow of each blending coal and the proportion of each coal in the total coal quantity according to the values of each time of the replenishment curve: coal 1 is 62%, coal 2 is 24%, and coal 3 is 14%.

[0077] Compared with the previous blending proportion, if the deviation value of coal 2 is greater than 5%, it means that the blending of coal 2 is not uniform.

[0078] The prediction data and curve trend obtained by the blending coal flow prediction model are also analyzed for instantaneous monitoring and total quantity monitoring. If the deviation value from the initial blending proportion is greater than 5%, the early warning of non-uniform blending is triggered.

[0079] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the above examples, those skilled in the art should understand that the specific embodiments of the present application can still be modified or replaced equivalently without departing from the spirit and scope of the present application. Any modification or equivalent replacement without departing from the spirit and scope of the present application should be covered within the protection scope of the claims of the present application.

Claims

1. A method for monitoring the uniformity of coal blending and combustion in a coal-fired unit, characterized in that: The following steps are involved: The first step is to select the initial proportion of each blended coal according to the reserves and planned consumption of each type of coal in the coal bunker (1); The second step is to monitor the delivery volume of different types of coal in real time, transmit the delivery volume to the host computer (6), and monitor the uniformity of coal blending and combustion on the host computer (6). Specifically, the monitoring is carried out from two perspectives: total amount monitoring and instantaneous monitoring: 2.

1. Instantaneous monitoring includes two methods: flow breakpoint monitoring and flow curve monitoring. Specifically: Flow breakpoint monitoring: The uniformity of coal blending can be judged by observing whether there are flow breakpoints in each blended coal; Flow curve monitoring: The uniformity of coal blending can be judged by observing whether the flow curve of each blended coal is stable; 2.

2. Total quantity monitoring: Obtain the instantaneous monitoring data of each blended coal over any period of time, calculate the sum of the instantaneous flow rates of each blended coal and the proportion of each type of coal in the total coal quantity, and then obtain the actual input proportion of each blended coal; Compare the actual input ratio of each blended coal with the set initial ratio of each blended coal. If the differences are within the predetermined threshold range, it means that the blending is uniform. If the deviation value of the actual input ratio of a certain blended coal is compared with its corresponding set initial ratio and exceeds the predetermined threshold range, it indicates that the blending is uneven.

2. The method for monitoring the uniformity of coal blending and combustion in a coal-fired unit according to claim 1, characterized in that: In step 2.1, the uniformity of the blended coal combustion is determined by observing whether there are flow breakpoints in each blended coal. Specifically: When there is a flow breakpoint, it means that the coal blending and combustion has uneven characteristics; when there is no flow breakpoint, it means that the coal blending and combustion has uniform characteristics.

3. The method for monitoring the uniformity of coal blending and combustion in a coal-fired unit according to claim 1, characterized in that: In step 2.1, the uniformity of the coal blending is judged by observing whether the flow curves of each blended coal are stable. Specifically, when the flow curve fluctuates, it indicates that the coal blending has uneven characteristics; when the flow curve is stable, it indicates that the coal blending has uniform characteristics.

4. The method for monitoring the uniformity of coal blending and combustion in a coal-fired unit according to claim 1, characterized in that: The actual input ratio of each blended coal is expressed as a n =Q n / Q 总 ×100%; where Q n Q is the total instantaneous flow of a certain coal accumulated over any period of time. 总 It is the sum of instantaneous flow rates of each type of coal accumulated over any period of time; The expression for comparing the actual input ratio of each blended coal with the set initial ratio of each blended coal is: Δ=|a n -a 0n |;a 0n is the initial proportion of coal n.

5. The method for monitoring the uniformity of coal blending and combustion in a coal-fired unit according to claim 1, characterized in that: In step 2.2, the predetermined threshold range is 5%.

6. A system for monitoring the uniformity of coal blending and combustion in a coal-fired unit, characterized in that: The invention comprises a host computer (6), a coal feeder (4), a belt conveyor (3) and a coal bunker (1); the coal feeders (4) are provided with a plurality of units for storing different types of coal; the coal feeders (4) are connected to the coal bunker (1) via a belt, and a monitoring device is provided on the belt for real-time monitoring of the conveying amount of different types of coal; the monitoring device is connected to the host computer (6) via a communication module (5), and the host computer (6) is connected to the coal feeders (4) for adjusting the input amount of each coal feeder (4); The host computer (6) is provided with an input module, a storage module, a flow breakpoint monitoring module, a flow curve monitoring module and a total amount monitoring module; a storage module for pre-determining a threshold range; Input module, used to input the initial proportion of each blended coal; The flow breakpoint monitoring module is used to determine the uniformity of coal blending by observing whether there are flow breakpoints in each blended coal; The flow curve monitoring module is used to determine the uniformity of coal blending by observing whether the flow curve of each blended coal is stable; The total amount monitoring module is used to obtain the instantaneous monitoring data of each blended coal in any period of time, calculate the total instantaneous flow of each blended coal and the proportion of each coal type in the total coal amount, and then obtain the actual input ratio of each blended coal; Compare the actual input ratio of each blended coal with the set initial ratio of each blended coal. If the differences are within the predetermined threshold range, it means that the blending is uniform. If the deviation value of the actual input ratio of a certain blended coal is compared with its corresponding set initial ratio and exceeds the predetermined threshold range, it indicates that the blending is uneven.

7. A system for monitoring coal blending and combustion uniformity of a coal-fired unit according to claim 6, characterized in that: The host computer (6) is also provided with a blending coal flow prediction model, which is used to mine the historical flow data of each blending coal, use a large amount of data internal information to establish a mathematical model and express the process state, and use the data-driven artificial neural network fault prediction technology to achieve the prediction of the blending flow of each blending coal and the early warning of the blending uniformity.

8. The system for monitoring the uniformity of coal blending and combustion of a coal-fired unit according to claim 6, characterized in that: The monitoring device adopts a flow sensor (2), a weight sensor or a volume sensor.

9. The system for monitoring coal blending and combustion uniformity of a coal-fired unit according to claim 6, characterized in that: The communication module (5) adopts a wired or wireless communication mode.

10. The system for monitoring coal blending and combustion uniformity of a coal-fired unit according to claim 6, characterized in that: The flow breakpoint monitoring module detects abnormal values ​​through LOF, isolation forest, K-Means clustering algorithm or One-class SVM algorithm.

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