A furnace sootblowing acoustic temperature measurement system

Abstract

The present invention relates to a furnace sootblowing sonic temperature measurement system, comprising: a sonic sootblower, a sonic detection module and a monitoring and control integrated machine; the sonic sootblower is arranged on the wall-wrapped tube of the boiler; the sonic detection module is arranged in the fire detection air duct of each layer of the boiler; the sonic detection module is connected to the monitoring and control integrated machine; the sonic detection module is used to receive the sonic waves emitted by the sonic sootblower and convert them into sonic electric signals; the monitoring and control integrated machine is used to determine the temperature distribution in the full combustion channel of the boiler according to the sonic electric signals; the monitoring and control integrated machine is also connected to the sonic sootblower; the monitoring and control integrated machine is also used to control the sonic sootblower to perform sootblowing according to the temperature distribution. The present invention can realize three-dimensional high-precision measurement of furnace temperature.

Description

Technical Field

[0001] The invention relates to the field of boiler soot blowing, and in particular to a furnace soot blowing sonic temperature measurement system. Background Art

[0002] In recent years, my country's coal-fired boiler units have undergone large-scale comprehensive energy-saving and environmental protection upgrades and ultra-low emission transformation projects, and have continuously eliminated and shut down units with backward production capacity and units that do not meet relevant mandatory standards.

[0003] The biggest problem of the boiler operating under the deep peak load regulation of 30% MCR is the problem of stable combustion. At this time, a large piece of coke may extinguish the fire. Recently, there are more and more cases of fire extinguishing due to coke dropping. The reasons for the boiler body are that the flame moves up after the low-nitrogen burner is modified, oxygen-deficient combustion, and insufficient oxygen supply of secondary air. The reasons for thermal engineering are that the flame combustion detection function of the means is insufficient, the swing of the fire detection optical fiber with the swing angle affects the flame detection (four-corner cut-circle furnace), the fire detection generally has the phenomenon of "peeking", the flame detection is not sensitive and accurate, the secondary air automatic control is difficult to put into use due to the lack of flame observation parameters, the fire extinguishing protection logic of FSSS is not perfect, and there is still a lack of detection means for the phenomenon of coke dropping in the furnace. The reasons for fuel are that coal blending has become a common phenomenon, deviating from the designed coal type and working conditions, some use multiple coal types to blend in the furnace, the secondary air cannot be controlled, the ignition distance of each burner is uneven, etc. The above problems bring huge challenges to the stable combustion of boilers under deep peak load regulation.

[0004] Improving boiler combustion efficiency has always been an important research topic for power generation companies. However, improving boiler efficiency requires a deeper understanding of the combustion conditions inside the furnace, so the furnace temperature is a very intuitive operating parameter. At present, coal-fired power companies are facing many problems and challenges:

[0005] 1. Low-nitrogen transformation: The low-nitrogen burner transformation of coal-fired boilers causes significant changes in the temperature field and air volume ratio in the furnace. The combustion conditions in the furnace after the transformation deviate greatly from the original design conditions, and there is a lack of effective monitoring methods.

[0006] 2. Blending of multiple coal types: The economic requirements of coal-fired power companies require a large amount of blending, mixed combustion and deep peak load regulation of units, which leads to unstable boiler combustion.

[0007] Traditional furnace temperature measurement devices are mainly divided into two types: contact and non-contact.

[0008] The contact type mainly includes thermocouples and furnace smoke temperature probes. Although simple and reliable, the measurement is intuitive; however, it can only achieve point measurement, the measurement temperature is limited, and continuous monitoring cannot be achieved.

[0009] The non-contact types are mainly 1. Laser measurement: The disadvantage is that the laser equipment consumes a lot of energy and is relatively expensive. The laser propagates in a straight line and has a low measurement resolution. It is difficult to measure the cross-sectional temperature at a few measurement points. 2. Furnace flame TV: You can see the combustion situation in the furnace: whether the fire is extinguished; it is impossible to obtain quantitative temperature information. 3. Infrared temperature measurement: Measure the infrared light intensity of the surface or area; the handheld type can only measure the temperature at the center of the flame. Since the furnace flue gas is gaseous, the temperature distribution is uneven, the composition is not fixed, and the presence of dust and fly ash particles makes the spectral wavelength and penetration of the composition uncertain, which leads to uncertainty in the measured area and large measurement errors. Summary of the invention

[0010] The purpose of the present invention is to provide a furnace sootblowing acoustic wave temperature measurement system to achieve three-dimensional high-precision measurement of the furnace temperature.

[0011] To achieve the above object, the present invention provides the following solutions:

[0012] A furnace sootblowing sonic temperature measurement system, comprising: a sonic sootblower, a sonic detection module and a monitoring and control integrated machine;

[0013] The sonic soot blower is arranged on the wall tube of the boiler; the sonic wave detection module is arranged in the fire detection air duct of each layer of the boiler; the sonic wave detection module is connected to the monitoring and control integrated machine; the sonic wave detection module is used to receive the sound waves emitted by the sonic soot blower and convert them into sound wave electrical signals; the monitoring and control integrated machine is used to determine the temperature distribution in the full combustion channel of the boiler according to the sound wave electrical signals; the monitoring and control integrated machine is also connected to the sonic soot blower; the monitoring and control integrated machine is also used to control the sonic soot blower to perform soot blowing according to the temperature distribution.

[0014] Optionally, the acoustic wave detection module includes an acoustic wave probe and an acoustic wave detector; the acoustic wave probe is used to receive the acoustic waves emitted by the acoustic wave soot blower and transmit the acoustic waves to the acoustic wave detector; the acoustic wave detector is connected to the monitoring and control integrated machine.

[0015] Optionally, there are multiple acoustic wave probes, and the multiple acoustic wave probes are arranged in one or more places in the furnace of the full combustion channel in the boiler, the SOFA wind layer, the horizontal flue or the tail flue.

[0016] Optionally, the data interface of the acoustic wave detector is a twisted pair communication interface.

[0017] Optionally, the sonic soot blower is welded to the wall tube of the boiler.

[0018] Optionally, the monitoring host and the embedded control host include an eight-way switch output control module; the eight-way switch output control module is connected to the wave detection module.

[0019] Optionally, the integrated monitoring and control machine also includes a monitoring host and an embedded control host; the monitoring host is used to determine the temperature distribution in the full combustion channel of the boiler according to the acoustic electrical signal; the embedded control host is used to control the acoustic soot blower to perform soot blowing according to the temperature distribution.

[0020] Optionally, the embedded control host also includes a comparator and a control module; the comparator is used to compare the temperature distribution and the set temperature range to obtain a comparison result; the control module is used to control the ultrasonic soot blower to perform soot blowing when the comparison result is that the temperature distribution exceeds the set temperature range.

[0021] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0022] The furnace sootblowing sonic temperature measurement system provided by the present invention comprises a sonic sootblower arranged on the wall-wrapped tube of the boiler; a sonic detection module arranged in the fire detection air duct of each layer of the boiler; a sonic detection module connected to a monitoring and control integrated machine; a sonic detection module used to receive the sonic waves emitted by the sonic sootblower and convert them into sonic electrical signals; a monitoring and control integrated machine used to determine the temperature distribution in the full combustion channel of the boiler according to the sonic electrical signals; a monitoring and control integrated machine also connected to the sonic sootblower; and a monitoring and control integrated machine also used to control the sonic sootblower to blow soot according to the temperature distribution. By measuring temperature through sonic waves, the measuring space is not limited, it is not affected by factors such as radiation, and the measuring accuracy is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 A schematic diagram of the structure of the furnace sootblowing acoustic wave temperature measurement system provided by the present invention;

[0025] Figure 2 A schematic diagram of the entire combustion path of the furnace sootblowing acoustic wave temperature measurement system provided by the present invention;

[0026] Figure 3 It is a diagram of the propagation path of sound waves.

[0027] Explanation of symbols:

[0028] 1-sonic soot blower, 2-sonic probe, 3-sonic detector, 4-monitoring and control integrated machine. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The purpose of the present invention is to provide a furnace sootblowing acoustic wave temperature measurement system to achieve three-dimensional high-precision measurement of the furnace temperature.

[0031] The principle of acoustic temperature measurement is based on the fact that the propagation speed of acoustic waves changes with temperature. The average transmission time on the path can be determined by measuring the time difference between the starting point and the receiving point of the acoustic wave. When the furnace is burning, the propagation path of the acoustic wave becomes longer, and the transmission time needs to be corrected for the delay effect of the wind speed.

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] like Figure 1 As shown, a furnace sootblowing acoustic wave temperature measurement system provided by the present invention comprises: an acoustic wave sootblower 1, an acoustic wave detection module and a monitoring and control integrated machine 4.

[0034] The sonic soot blower 1 is arranged on the wall tube of the boiler; the sonic wave detection module is arranged in the fire detection air duct of each layer of the boiler; the sonic wave detection module is connected to the monitoring and control integrated machine 4; the sonic wave detection module is used to receive the sound waves emitted by the sonic wave soot blower 1 and convert them into sound wave electrical signals; the monitoring and control integrated machine 4 is used to determine the temperature distribution in the full combustion channel of the boiler according to the sound wave electrical signals; the monitoring and control integrated machine 4 is also connected to the sonic wave soot blower 1; the monitoring and control integrated machine 4 is also used to control the sonic wave soot blower 1 to perform soot blowing according to the temperature distribution.

[0035] In practical applications, the acoustic wave detection module includes an acoustic wave probe 2 and an acoustic wave detector 3; the acoustic wave probe 2 is used to receive the acoustic waves emitted by the acoustic wave soot blower 1 and transmit the acoustic waves to the acoustic wave detector 3; the acoustic wave detector 3 is connected to the monitoring and control integrated machine 4.

[0036] In practical applications, the acoustic wave probes 2 are provided in plurality, and the plurality of acoustic wave probes 2 are arranged in one or more places in the furnace of the full combustion channel in the boiler, the SOFA wind layer, the horizontal flue or the tail flue.

[0037] In practical applications, the data interface of the acoustic wave detector 3 is a twisted pair communication interface.

[0038] In practical applications, the sonic soot blower 1 is welded on the wall tube of the boiler.

[0039] In practical applications, the monitoring host and the embedded control host include an eight-way switch output control module; the eight-way switch output control module is connected to the wave detection module.

[0040] In actual applications, the monitoring and control integrated machine 4 also includes a monitoring host and an embedded control host; the monitoring host is used to determine the temperature distribution in the full combustion channel of the boiler according to the acoustic electrical signal; the embedded control host is used to control the acoustic soot blower 1 to perform soot blowing according to the temperature distribution.

[0041] In practical applications, the embedded control host also includes a comparator and a control module; the comparator is used to compare the temperature distribution and the set temperature range to obtain a comparison result; the control module is used to control the acoustic soot blower 1 to perform soot blowing when the comparison result is that the temperature distribution exceeds the set temperature range.

[0042] like Figure 2 As shown, the present invention can realize the temperature distribution measurement of the main combustion zone A of the furnace by setting up acoustic wave detection points at the bottom of the furnace and the middle SOFA wind layer, the temperature distribution of the shielding angle zone B can be realized through the acoustic wave measurement points of the SOFA wind layer and the horizontal flue, the temperature distribution of the horizontal flue C can be realized through the acoustic wave measurement points of the horizontal flue, the temperature distribution of the lower turning zone can be realized through the acoustic wave measurement points of the horizontal flue and the tail flue, and the temperature distribution of the zone E of the zone can be realized through the acoustic wave measurement points of the tail flue. Therefore, the temperature distribution measurement of the whole combustion channel can be realized. Among them, in the present invention, two acoustic wave probes 2 A-1 and A-4 are set at the bottom of the furnace, two acoustic wave probes 2 AB-1 and AB-4 are set in the middle SOFA wind layer, four acoustic wave probes 2 B-1, B-4, C-1, and C-4 are set in the horizontal flue, and four acoustic wave probes 2 D-1, D-4, E-1, and E-4 are set in the tail flue. In practical applications, the position and number of acoustic wave probes can be determined according to the actual situation of the power plant boiler.

[0043] This system uses the noise of the sootblower when blowing soot as the measurement sound source, and can measure the temperature of each zone. During measurement, the sootblower should blow soot in an orderly manner under computer control.

[0044] If only the furnace temperature needs to be measured, a layer of sonic wave probes 2 can be installed on the bottom burner (4) and the SOFA wind layer (4), respectively, so that three-dimensional temperature measurement of the furnace can be achieved.

[0045] 1) Sonic soot blower 1

[0046] The sound of soot blowing is very loud, and its noise can be used as the sound source for acoustic temperature measurement. Only one sound source is allowed during acoustic wave measurement, so multiple soot blowers cannot blow soot at the same time. The start control command of the soot blower is connected to the measurement unit, and the measurement unit can determine the location of the sound source. Among them, the propagation path of the sound wave is as follows Figure 3 As shown, Figure 3 Although there are two sonic soot blowers in the boiler, only one sonic soot blower is in operation during the actual temperature measurement. In order to make the temperature measurement in the actual boiler more accurate, each sonic soot blower must be operated in turn.

[0047] 2) Sonic wave probe 2

[0048] The furnace area acoustic wave probe 2 is installed in the fire detection air duct and cooled by secondary air. Each probe converts the sound intensity signal into a current signal, which is detected and processed by the acoustic wave detector 3. The acoustic wave probe includes 10 shear wave output terminals.

[0049] 3) Sound wave detector 3

[0050] Each acoustic wave detector 3 can input eight-way acoustic signals at the same time, and outputs a twisted pair communication interface, which is connected to the background host, and the working power supply is 24VDC. The module is installed vertically on the guide rail or the terminal box base. Among them, each acoustic wave detector 3 includes 10 transverse wave input terminals.

[0051] 4) Monitoring and control integrated machine 4

[0052] 10-inch touch screen all-in-one machine, including: monitoring host and embedded control host. The monitoring and control all-in-one machine 4 is equipped with an eight-way switch output control module. Each eight-way switch output control module can realize eight-way switch output, the communication interface is Tbus, connected to the background control host, the working power supply is 24VDC, and the module appearance is installed vertically on the guide rail or terminal box base.

[0053] Embedded control host parameters:

[0054] Working power supply: +5VDC, two-way

[0055] CPU module: 5x86-800MHz

[0056] Ethernet network interface: 100Mbps, 2

[0057] RS485 interface: 1

[0058] RS232 interface: 1

[0059] Tbus interface: 1 (connected to acoustic wave detector 3).

[0060] The sonic soot blower 1 is installed on the furnace wall tube by welding. When the sonic soot blower 1 blows soot, the sound waves emitted by the sonic soot blower 1 are received by the sonic probe 2 installed in the fire detection air duct and transmitted to the sonic detector 3 (input end). The sonic detector 3 will detect the sound intensity of the sound signal and convert the sound signal into an electrical signal and transmit it to the eight-way switch output control module (output end), and finally transmit it to the monitoring and control integrated machine 4. After calculation and analysis by the control software, the propagation time of the sound signal from the sound generator to the sonic probe 2 is obtained. Thus, the sound wave propagation rate is obtained, and then the temperature condition on the sound signal propagation path is obtained. The equipment is connected by cables.

[0061] The propagation speed of sound waves changes with the temperature of the medium. The relationship between the propagation speed of sound waves and the temperature of the medium is obtained from the gas equation in thermodynamics and the sound wave equation in acoustics as follows:

[0062] C=f(K,R,M,T)

[0063] c - the speed of sound in the medium

[0064] R——gas constant

[0065] k——Adiabatic index of gas

[0066] M——gas molecular weight

[0067] T——gas temperature

[0068] From this, the temperature of the medium can be calculated.

[0069] The present invention is a furnace sootblowing sonic temperature measurement system, which can effectively blow soot in the soot accumulation area of ​​a power station boiler and monitor the temperature inside the furnace. The temperature measurement system uploads the temperature inside the furnace to the monitoring and control integrated machine 4, and obtains the soot accumulation in the area through temperature analysis and controls the sootblower action. The system provided by the present invention has high accuracy and is not affected by factors such as radiation; the measurement temperature range is wide and can be used within the full load range of the boiler; the measurement space is not limited, and not only the average temperature can be measured, but also the furnace temperature field distribution can be measured; the measurement sensitivity is high, the real-time performance is good, and the maintainability is good.

[0070] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0071] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A furnace sootblowing acoustic wave temperature measurement system, characterized in that: include: Acoustic soot blower, acoustic detection module and integrated monitoring and control unit; The sonic soot blower is arranged on the wall-wrapped tube of the boiler; the sonic detection module is arranged in the fire detection air duct of each layer of the boiler; the sonic detection module is connected to the monitoring and control integrated machine; the sonic detection module is used to receive the sound waves emitted by the sonic soot blower and convert them into sound wave electrical signals; the monitoring and control integrated machine is used to determine the temperature distribution in the full combustion channel of the boiler according to the sound wave electrical signals; the monitoring and control integrated machine is also connected to the sonic soot blower; the monitoring and control integrated machine is also used to control the sonic soot blower to blow soot according to the temperature distribution; The monitoring and control integrated machine also includes a monitoring host and an embedded control host; the monitoring host is used to determine the temperature distribution in the full combustion channel of the boiler according to the acoustic wave electrical signal; the embedded control host is used to control the acoustic wave soot blower to blow soot according to the temperature distribution; the monitoring host and the embedded control host include an eight-way switch output control module; the eight-way switch output control module is connected to the wave detection module; There are multiple sonic soot blowers, and the multiple sonic soot blowers operate in turn.

2. The furnace sootblowing acoustic wave temperature measurement system according to claim 1, characterized in that: The acoustic wave detection module comprises an acoustic wave probe and an acoustic wave detector; the acoustic wave probe is used to receive the acoustic waves emitted by the acoustic wave soot blower and transmit the acoustic waves to the acoustic wave detector; the acoustic wave detector is connected to the monitoring and control integrated machine.

3. The furnace sootblowing acoustic wave temperature measurement system according to claim 2, characterized in that: There are multiple acoustic wave probes, and the multiple acoustic wave probes are arranged in one or more places in the furnace of the full combustion channel, the SOFA wind layer, the horizontal flue or the tail flue in the boiler.

4. The furnace sootblowing acoustic wave temperature measurement system according to claim 2, characterized in that: The data interface of the acoustic wave detector is a twisted pair communication interface.

5. The furnace sootblowing acoustic wave temperature measurement system according to claim 1, characterized in that: The sonic soot blower is welded on the wall tube of the boiler.

6. The furnace sootblowing acoustic wave temperature measurement system according to claim 1, characterized in that: The embedded control host also includes a comparator and a control module; the comparator is used to compare the temperature distribution and the set temperature range to obtain a comparison result; the control module is used to control the sonic soot blower to perform soot blowing when the comparison result is that the temperature distribution exceeds the set temperature range.

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