阅读说明：本技术 一种锅炉水冷壁灰污监测系统 (Boiler water-cooled wall dirt monitoring system ) 是由 邹洋 张翔 闫凯 乌晓江 于 2020-07-01 设计创作，主要内容包括：本发明提供了一种锅炉水冷壁灰污监测系统,所述锅炉水冷壁上有N个吹灰器,N≥1,N个吹灰器位于M个不同高度,M≥1,每个高度有n个吹灰器,1≤n≤N,其特征在于,所述监测系统包括J个鳍片热电偶、K个管壁热电偶、温度数据采集器、数据处理平台。本发明将鳍片热电偶布置在每一个吹灰器附近,一方面所需的鳍片热电偶数量较少,另一方面一旦监测到该热电偶所在的水冷壁区域污染率高,可通过控制该热电偶附近的吹灰器进行吹灰操作,保持受热面的清洁并监测吹灰效果。(The invention provides a boiler water wall ash and dirt monitoring system, wherein N soot blowers are arranged on a boiler water wall, N is more than or equal to 1, the N soot blowers are positioned at M different heights, M is more than or equal to 1, each height is provided with N soot blowers, N is more than or equal to 1 and less than or equal to N, and the boiler water wall ash and dirt monitoring system is characterized by comprising J fin thermocouples, K tube wall thermocouples, a temperature data collector and a data processing platform. According to the invention, the fin thermocouples are arranged near each soot blower, so that on one hand, the number of the required fin thermocouples is small, and on the other hand, once the pollution rate of a water wall area where the thermocouples are located is high, soot blowing operation can be carried out by controlling the soot blowers near the thermocouples, the heating surface is kept clean, and the soot blowing effect is monitored.)

1. A boiler water wall ash and dirt monitoring system is characterized in that the monitoring system comprises J fin thermocouples, K tube wall thermocouples, a temperature data collector and a data processing platform, J is larger than or equal to 1 and smaller than or equal to N, and K is larger than or equal to 1 and smaller than or equal to J;

j fin thermocouples are respectively arranged near the J soot blowers, the jth fin thermocouple is arranged at a water-cooled wall fin of the boiler water-cooled wall within a certain distance D from the jth soot blower, J is 1, …, J, and the fin temperature of the water-cooled wall fin is measured by the fin thermocouples;

k tube wall thermocouples are respectively arranged at the outermost part of the back fire side of the water wall tube of the boiler water wall adjacent to the K fin thermocouples and are used for measuring the tube wall temperature of the water wall tube;

the temperature of the fins measured by the fin thermocouples and the temperature of the tube wall measured by the tube wall thermocouples are accessed to the data processing platform through the temperature data collector;

the data processing platform is based on the temperature difference between the temperature of the fins and the temperature of the tube wall, and when the fire facing sides of the water wall tube and the water wall fins are in a clean state, the temperature difference is large; when the fire facing sides of the water wall tubes and the water wall fins are in an ash state, the temperature difference is small; the more serious the ash contamination of the fire facing side of the water wall tube and the water wall fin is, the smaller the temperature difference value is, and the ash contamination degree, namely the pollution rate, of each soot blower area is obtained through linear operation by the data processing platform.

2. The boiler water wall soot monitoring system as set forth in claim 1, wherein the number J of said fin thermocouples is equal to the number N of said soot blowers, and each of said soot blowers corresponds to one of said fin thermocouples.

3. The boiler water wall fouling monitoring system of claim 2, wherein the number K of the tube wall thermocouples is much smaller than the number J of the fin thermocouples, the number K of the tube wall thermocouples is less than or equal to M, and at most one tube wall thermocouple is arranged at each height.

4. The boiler water wall soot monitoring system as set forth in claim 3, wherein, assuming that the pollution rate of the current soot blower area is W, there are:

in the formula, Ta is the temperature of the fin measured by the fin thermocouple beside the soot blower corresponding to the current soot blower area;

tb is the pipe wall temperature measured by the pipe wall thermocouple at the same height of the soot blower corresponding to the current soot blower area;

t0 is the difference between Ta and Tb in the clean state of the heating surface, and is calibrated after the soot blowing of the current soot blower is finished in the initial stage of the operation of the boiler.

5. The boiler water wall fouling monitoring system of claim 1, wherein the distance D is 1.5 meters.

6. The boiler water wall soot monitoring system of claim 1, wherein said soot blower is a steam soot blower, a hydraulic soot blower or a sound wave soot blower.

7. The boiler water wall ash monitoring system of claim 1, wherein whether the soot blowing operation is performed is judged by a boiler operator or the data processing platform based on the pollution rate of the soot blower area obtained by the data processing platform, so as to keep the water wall of the boiler clean.

Technical Field

The invention relates to the technical field of intelligent control systems of combustion equipment, in particular to a boiler water wall ash and dirt monitoring system.

Background

The boiler is a key device for the operation of a power station, and during the operation process of the coal-fired boiler, a large amount of ash residues which are byproducts of coal combustion in the boiler can be generated, so that ash and dirt with different degrees inevitably appear on a heating surface. Soot blowing is an effective means of removing soot and maintaining the heated surfaces of a boiler clean. The soot blower uses certain soot blowing medium (water, steam, sound wave, etc.) to blow the heating surface to remove the surface dirt, so that the surface of the soot blower returns to a clean state. The soot blowing system is an important means for improving the availability ratio of the unit and ensuring the safe and economic operation of the unit.

At present, the soot blowing operation of a large-scale power station boiler generally adopts a timed and quantitative program control mode. The method is carried out under the condition that the actual soot-blowing state of the heating surface is not known, the phenomenon of insufficient soot blowing or excessive soot blowing is inevitably generated, and the soot blowing time and the soot blowing position are mostly determined by experience, so that the method has artificial subjectivity. In addition, if the soot blowing period is too short, unnecessary soot blowing working medium consumption is caused, the service life of a heating surface and the service life of a soot blower are reduced, and extra cost overhead is increased; if the soot blowing period is too long, the soot layer is too thick and difficult to clean, and the soot blowing effect is poor. Therefore, the method monitors the ash on the water cooling wall of the boiler in real time, and reasonably puts the soot blowing system into use, so that the boiler obtains better economic benefit, and is very important.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the soot blowing system is easy to generate insufficient soot blowing, excessive soot blowing and improper soot blowing period in the operation process.

In order to solve the technical problems, the technical scheme of the invention provides a boiler water wall ash and dirt monitoring system, wherein N soot blowers are arranged on a boiler water wall, N is more than or equal to 1, the N soot blowers are positioned at M different heights, M is more than or equal to 1, each height is provided with N soot blowers, N is more than or equal to 1 and less than or equal to N, the monitoring system is characterized by comprising J fin thermocouples, K tube wall thermocouples, a temperature data acquisition device and a data processing platform, J is more than or equal to 1 and less than or equal to N, and K is more than or equal to 1 and less than or equal to J;

j fin thermocouples are respectively arranged near the J soot blowers, the jth fin thermocouple is arranged at a water-cooled wall fin of the boiler water-cooled wall within a certain distance D from the jth soot blower, J is 1, …, J, and the fin temperature of the water-cooled wall fin is measured by the fin thermocouples;

k tube wall thermocouples are respectively arranged at the outermost part of the back fire side of the water wall tube of the boiler water wall adjacent to the K fin thermocouples and are used for measuring the tube wall temperature of the water wall tube;

the temperature of the fins measured by the fin thermocouples and the temperature of the tube wall measured by the tube wall thermocouples are accessed to the data processing platform through the temperature data collector;

the data processing platform is based on the temperature difference between the temperature of the fins and the temperature of the tube wall, and when the fire facing sides of the water wall tube and the water wall fins are in a clean state, the temperature difference is large; when the fire facing sides of the water wall tubes and the water wall fins are in an ash state, the temperature difference is small; the more serious the ash contamination of the fire facing side of the water wall tube and the water wall fin is, the smaller the temperature difference value is, and the ash contamination degree, namely the pollution rate, of each soot blower area is obtained through linear operation by the data processing platform.

Preferably, the number J of the fin thermocouples is equal to the number N of the soot blowers, and each soot blower corresponds to one fin thermocouple.

Preferably, the number K of the tube wall thermocouples is far smaller than the number J of the fin thermocouples, the number K of the tube wall thermocouples is less than or equal to M, and at most one tube wall thermocouple is arranged at each height.

Preferably, assuming that the pollution rate of the current sootblower zone is W, there are:

in the formula, Ta is the temperature of the fin measured by the fin thermocouple beside the soot blower corresponding to the current soot blower area;

tb is the pipe wall temperature measured by the pipe wall thermocouple at the same height of the soot blower corresponding to the current soot blower area;

t0 is the difference between Ta and Tb in the clean state of the heating surface, and is calibrated after the soot blowing of the current soot blower is finished in the initial stage of the operation of the boiler.

Preferably, the distance D is 1.5 meters.

Preferably, the soot blower is a steam soot blower, a hydraulic soot blower or a sound wave soot blower.

Preferably, whether the soot blowing operation is performed or not is judged by a boiler operator or the data processing platform based on the pollution rate of the soot blower area obtained by the data processing platform, so that the cleanness of the water wall of the boiler is kept.

By adopting the scheme, the invention has the beneficial effects that:

(1) according to the invention, the fin thermocouples are arranged near each soot blower, so that on one hand, the number of the required fin thermocouples is small, and on the other hand, once the pollution rate of a water wall area where the thermocouples are located is high, soot blowing operation can be carried out by controlling the soot blowers near the thermocouples, the heating surface is kept clean, and the soot blowing effect is monitored;

(2) the invention arranges at most one tube wall thermocouple on each water-cooled wall beside the soot blower at the same height, thereby greatly reducing the number of the tube wall thermocouples, greatly reducing the risk of damaging the water-cooled wall in the installation process of the tube wall thermocouples and being beneficial to large-scale popularization and use.

Drawings

FIG. 1 is a schematic diagram of a soot blower and thermocouple arrangement on one wall of a water wall of a boiler in an embodiment of the present invention;

FIG. 2 is a schematic diagram of the mounting locations of fin thermocouples and tube wall thermocouples in an embodiment of the present invention;

in the figure, 1, a boiler water wall; a-1-c-3, a soot blower; 2. a wall temperature thermocouple; 3. a fin thermocouple; 4. a water wall tube; 5. water-cooled wall fins; 6. a temperature data collector; 7. a data processing platform.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

As shown in fig. 1 and 2, a boiler water wall ash monitoring system provided by the embodiment of the invention comprises 9 soot blowers a-1-c-3 on a boiler water wall 1, 9 fin thermocouples 3 and 2 wall heating thermocouples 2. Each soot blower corresponds to one fin thermocouple 3, and the fin thermocouples 3 are arranged beside the corresponding soot blowers at positions close to the central line of the furnace wall. The 2 wall thermocouple heaters 2 are arranged beside the fin thermocouples 3 at the lowest layer and the uppermost layer near the center of the furnace wall.

The fin temperature measured by the fin thermocouple 3 and the pipe wall temperature measured by the pipe wall thermocouple 2 are connected to the data processing platform 7 through the temperature data collector 6, and the data processing platform 7 obtains the soot degree, namely the pollution rate, of each soot blower area through linear operation based on the temperature difference between the fin temperature and the pipe wall temperature.

The working principle of the boiler water wall ash and dirt monitoring system is as follows:

when the water cooling walls where the fin thermocouple 3 and the wall temperature thermocouple 2 are located are in a clean state, the temperature difference measured by the fin thermocouple 3 and the wall temperature thermocouple 2 is large; when the water cooling walls where the fin thermocouples 3 and the wall temperature thermocouples 2 are located are in an ash state, the temperature difference measured by the fin thermocouples 3 and the wall temperature thermocouples 2 is small; the more serious the ash on the water cooling wall where the fin thermocouple 3 and the wall temperature thermocouple 2 are located is, the smaller the temperature difference value measured by the fin thermocouple 3 and the wall temperature thermocouple 2 is.

If the pollution rate of the current soot blower area is W, then:

in the formula, Ta is the temperature of the fin measured by the fin thermocouple beside the soot blower corresponding to the current soot blower area;

tb is the pipe wall temperature measured by the pipe wall thermocouple at the same height of the soot blower or the lower soot blower corresponding to the current soot blower area;

t0 is the difference between Ta and Tb in the clean state of the heating surface, and is calibrated after the soot blowing of the current soot blower is finished in the initial stage of the operation of the boiler.

According to the boiler water wall soot monitoring system provided by the invention, the fin thermocouples are arranged near each soot blower, so that on one hand, the number of the required fin thermocouples is small, and on the other hand, once the contamination rate of a water wall area where the thermocouples are located is high, soot blowing operation can be carried out by controlling the soot blowers near the thermocouples, the heating surface is kept clean, and the soot blowing effect is monitored. The invention greatly reduces the number of the tube wall thermocouples, can effectively reduce the risk of damaging the water cooling wall in the installation process of the tube wall thermocouples, and is beneficial to large-scale popularization and use.