Method for measuring temperature of flue gas in waste incinerator

Abstract

The application provides a waste incinerator flue gas temperature measurement method, and belongs to the technical field of temperature detection. The method comprises the following steps: determining required calibration particles according to the type of fuel in the furnace and the state of combustion reaction; the calibration particles do not participate in the combustion reaction and are in different excited states when the temperature is different. The calibration particles enter the furnace along with the gas, the excited state level of the calibration particles in the corresponding volume range in the furnace is identified and determined through multiple identifiers, and the spatial distribution of each calibration particle in the furnace is simulated according to the feedback content of each identifier, and the total temperature distribution in the furnace is inferred in combination with the determined excited state level. The waste incinerator flue gas temperature measurement method provided by the application has a wide sample range, low detection cost, strong reference data, and can truly reflect the temperature level in the furnace.

Description

Technical Field

[0001] This invention belongs to the field of temperature detection technology, and more specifically, relates to a method for measuring the temperature of flue gas inside a waste incinerator. Background Technology

[0002] The harmless treatment of municipal solid waste has become an important task for environmental protection departments. Methods of municipal solid waste treatment include landfilling and incineration. While landfilling does not pollute the atmosphere, it requires a large amount of land. For every city, using large amounts of land for landfilling is an unsustainable strategy. Therefore, incineration is becoming increasingly accepted by the public. Although incineration is a feasible method, the harmful exhaust gases produced by the furnace, if not thoroughly treated before being released into the atmosphere, can cause smog and release toxic and odorous gases, polluting the environment and endangering public health. This necessitates accurate monitoring of conditions such as furnace temperature during the incineration process.

[0003] Due to the large volume of the furnace, temperatures vary depending on the location within the furnace. Determining the temperature distribution within the furnace intuitively and accurately is a key technical challenge. Current technologies often use sensors at specific locations to detect temperature; however, these sensors require continuous cooling to ensure long-term use, leading to high costs. Furthermore, because they can only detect temperatures at specific locations, the data's reliability is limited. Summary of the Invention

[0004] The purpose of this invention is to provide a method for measuring the temperature of flue gas inside a waste incinerator, aiming to solve the problems of high cost and low data reliability when detecting the temperature inside the furnace.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a method for measuring the temperature of flue gas inside a waste incinerator, comprising:

[0006] The required calibration particles are determined based on the type of fuel in the furnace and the state of the combustion reaction. These calibration particles do not participate in the combustion reaction and will be in different excited states at different temperatures.

[0007] The calibration particles are introduced into the furnace along with the gas. Multiple identifiers identify and determine the excited state level of the calibration particles within the corresponding volume range of the furnace. Based on the feedback from each identifier, the spatial distribution of each calibration particle in the furnace is simulated. Combined with the determined excited state level, the overall temperature distribution in the furnace is inferred.

[0008] In one possible implementation, determining the required calibration particles based on the type of fuel in the furnace and the state of the combustion reaction includes:

[0009] The calibration particles of appropriate volume and mass are selected based on the velocity and flow rate of the gas entering the furnace.

[0010] In one possible implementation, the step of allowing the calibration particles to enter the furnace along with the gas includes:

[0011] The calibration particles are magnetized so that they have the same magnetic properties, which generates a repulsive force, ensuring that the calibration particles are spaced apart.

[0012] In one possible implementation, the calibration particles do not participate in the combustion reaction and are in different excited states at different temperatures, including:

[0013] The calibration particles flow through the burning fuel and continue to move upward with the gas. The calibration particles will be in different excited states depending on the temperature of their surrounding environment.

[0014] In one possible implementation, identifying and determining the excited state level of the calibration particles within a corresponding volume range inside the furnace using multiple identifiers includes:

[0015] The identifier sends a pulse signal into the furnace that can only act on the calibration particles; the calibration particles have different sensitivities to the pulse signal depending on their excited state.

[0016] The identifier infers the level of the excited state within a certain volume range based on the received returned pulse signal, and determines the position of the calibrated particle within the corresponding range.

[0017] In one possible implementation, the different excited states of the calibration particles result in different degrees of sensitivity to the pulse signal, including:

[0018] When the excited states are different, the amount of absorption and reflectivity of the calibrated particles to the pulse signal are different; the identifier infers the level of the excited state based on the time, amount and direction of the pulse signal return.

[0019] In one possible implementation, the identifier infers the level of the excited state within a certain volume range based on the received returned pulse signal, including:

[0020] The identifier infers the spatial position of the calibrated particles within the corresponding range based on the time interval between the emission and return of the pulse signal, the amount and angle of the returned pulse signal, and the current position of the identifier.

[0021] In one possible implementation, simulating the spatial distribution of each of the calibrated particles within the furnace based on the feedback from each of the identifiers includes:

[0022] By changing the specifications of the pulse signal, the pulse signal can detect and cover the calibration particles at different distances. The contents determined by the pulse signal in different states are integrated and optimized, and finally the spatial distribution of the calibration particles and the level of the excited state at different distances are determined.

[0023] In one possible implementation, simulating the spatial distribution of each of the calibrated particles within the furnace based on the feedback from each of the identifiers includes:

[0024] Based on the spatial positions of the multiple identifiers relative to the furnace, the spatial range that each identifier can detect is integrated and filled to finally simulate the spatial model when the calibrated particles fill the furnace cavity;

[0025] Based on the spatial model and the predicted temperature levels, the spatial temperature distribution of the entire furnace is inferred.

[0026] In one possible implementation, after inferring the overall temperature distribution within the furnace based on the determined excited state level, the following further step is added:

[0027] The outflowing calibration particles are recovered using magnetic force, and then the recovered calibration particles are demagnetized and reused.

[0028] The beneficial effects of the flue gas temperature measurement method in a waste incinerator provided by this invention are as follows: Compared with the prior art, the method first determines the required calibration particles based on the type of fuel and the state of the combustion reaction in the furnace. These calibration particles do not participate in the combustion reaction and are in different excited states at different temperatures. The calibration particles are then introduced into the furnace along with the gas. Multiple identifiers identify and determine the excited state level of the calibration particles within the corresponding volume range of the furnace. Based on the feedback from each identifier, the spatial distribution of each calibration particle in the furnace is simulated, and the overall temperature distribution inside the furnace is inferred by combining the determined excited state levels.

[0029] In this application, the excited states of multiple calibrated particles in the furnace are identified and determined by an identifier, which ultimately yields the overall temperature distribution in the furnace. The sample size is relatively large, the detection cost is low, and the obtained data is highly reliable and can accurately reflect the temperature level inside the furnace. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 A flowchart illustrating the method for measuring flue gas temperature inside a waste incinerator, as provided in an embodiment of the present invention. Detailed Implementation

[0032] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0033] Please see Figure 1 The present invention will now describe the method for measuring the temperature of flue gas inside a waste incinerator. The method for measuring the temperature of flue gas inside a waste incinerator includes:

[0034] The required calibration particles are determined based on the type of fuel in the furnace and the state of the combustion reaction. The calibration particles do not participate in the combustion reaction and will be in different excited states at different temperatures.

[0035] The calibration particles are introduced into the furnace along with the gas. Multiple identifiers identify and determine the excited state level of the calibration particles within the corresponding volume range of the furnace. Based on the feedback from each identifier, the spatial distribution of each calibration particle in the furnace is simulated. Combined with the determined excited state level, the overall temperature distribution in the furnace is inferred.

[0036] The beneficial effects of the flue gas temperature measurement method in a waste incinerator provided by this invention are as follows: Compared with the prior art, the method first determines the required calibration particles based on the type of fuel and the state of the combustion reaction in the furnace. These calibration particles do not participate in the combustion reaction and are in different excited states at different temperatures. The calibration particles are then introduced into the furnace along with the gas. Multiple identifiers identify and determine the excited state level of the calibration particles within the corresponding volume range of the furnace. Based on the feedback from each identifier, the spatial distribution of each calibration particle in the furnace is simulated, and the overall temperature distribution inside the furnace is inferred by combining the determined excited state levels.

[0037] In this application, the excited states of multiple calibrated particles in the furnace are identified and determined by an identifier, which ultimately yields the overall temperature distribution in the furnace. The sample size is relatively large, the detection cost is low, and the obtained data is highly reliable and can accurately reflect the temperature level inside the furnace.

[0038] Currently, furnace temperature control relies solely on thermometers installed on the furnace walls. However, due to uneven combustion within the furnace or the large width of the furnace, the measured temperatures around the furnace walls often differ significantly, rendering these readings practically meaningless. Furthermore, existing direct-type thermometers, being exposed to the elements, experience a direct reduction in radiant heat from the flue gas during extraction, which also leads to lower measured temperatures.

[0039] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, the required calibration particles are determined based on the type of fuel in the furnace and the state of the combustion reaction, including:

[0040] Select calibration particles of appropriate volume and mass based on the velocity and flow rate of the gas entering the furnace.

[0041] Due to the complex composition of fuels such as waste and biomass, it is impossible to determine the composition of substances formed during combustion and the combustion conditions, making segmented combustion impossible. The content of CO, NO, etc., inside the furnace cannot be measured, and online monitoring devices are only installed after the induced draft fan, thus preventing combustion optimization. Existing online monitoring devices have exposed probes, which are highly susceptible to flue gas contamination and are not heat-resistant, therefore they can only measure the composition of flue gas after treatment. Therefore, to solve the above problems, it is necessary to propose a measuring device for real-time monitoring of furnace temperature to address the existing technical issues.

[0042] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, the method of allowing calibration particles to enter the furnace along with the gas includes:

[0043] Magnetizing the calibration particles makes them magnetically identical, generating a repulsive force and ensuring that the calibration particles are spaced apart.

[0044] During normal operation, the furnace temperature directly affects the boiler's combustion safety and efficiency, influencing pollutant production and emissions. Accurate measurement of furnace temperature and composition is crucial for judging, predicting, and diagnosing the boiler's combustion status. Currently, there are two patented technologies for measuring high-temperature flue gas temperature in the furnace: direct and indirect methods. The direct method for measuring furnace gas temperature employs various insulation methods and high-temperature resistant materials to achieve direct temperature measurement at high temperatures. However, this method still faces challenges in continuous high-temperature measurement and low accuracy. Current solutions include using high-temperature resistant filling materials to address this issue, or employing water-cooled jackets and exhaust-type double-layer heat shields to reduce measurement errors caused by heat transfer at thermocouple junctions. Furthermore, the direct method requires cyclic cooling of the measuring devices, leading to significant resource waste and complicating the overall furnace structure.

[0045] In contrast to the indirect method, quantitative sampling of high-temperature flue gas at fixed points within the furnace is required for quantitative heat exchanger calculations. The temperature of the high-temperature flue gas is then inferred from existing flue gas property parameters. This inference method often amplifies measurement errors significantly. Furthermore, the indirect method itself suffers from inaccuracies in the measuring devices, leading to discrepancies between the final result and the actual temperature. This results in an inability to accurately and effectively measure the temperature, making the final result less reliable.

[0046] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, the calibration particles do not participate in the combustion reaction and are in different excited states at different temperatures, including:

[0047] The calibration particles flow through the burning fuel and continue to move upward with the gas. The calibration particles will be in different excited states depending on the temperature of their surrounding environment.

[0048] With continuous technological innovation, the information capabilities of related visual sensors and computers have been developed and improved. Based on the above reasons, if the temperature of each area inside the furnace is accurately measured and the flow velocity of the gas at each location inside the furnace is inferred, the combustion of fuel inside the furnace can be analyzed and judged more accurately, making the final result easier for subsequent analysis and adjustment.

[0049] This application integrates the direct and indirect methods in the prior art, and combines related content such as physical fluid mechanics and computer fluid simulation technology to ultimately conduct a more accurate analysis and judgment of the combustion and gas flow in the entire furnace, and more importantly, to accurately determine the temperature inside the furnace.

[0050] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, identifying and determining the excited state level of calibration particles within a corresponding volume range inside the incinerator using multiple identifiers includes:

[0051] The identifier sends a pulse signal into the furnace that can only act on the calibration particles; the sensitivity of the calibration particles to the pulse signal varies depending on their excited state.

[0052] The identifier infers the level of the excited state within a certain volume range based on the received returned pulse signals and determines the position of the calibrated particles within the corresponding range.

[0053] To illustrate this in more detail, this application incorporates calibration particles into the gas supplied to the furnace. These calibration particles are relatively stable, and more importantly, their state changes as their temperature rises, allowing them to enter different excited states. It is based on these excited states that the temperature at different locations within the furnace can be determined. In practical applications, multiple calibration particles follow the gas into the furnace and pass through the combustion zone. The calibration particles themselves do not participate in the combustion reaction and therefore move upwards with the gas. Due to the large number of calibration particles, and for the reasons described above, they can reach various parts of the furnace.

[0054] Although the temperature inside the furnace is high, there will still be certain differences in temperature at different locations inside the furnace. It is these differences that allow particles to be in different excited states. By accurately detecting the excited states of the particles, the temperature at the corresponding location inside the furnace can be inferred.

[0055] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, the sensitivity of the calibration particles to pulse signals varies depending on the excited state of the particles, including:

[0056] When the excited state is different, the amount of absorption and reflectivity of the calibrated particle to the pulse signal are different; the recognizer infers the level of the excited state based on the time, amount and direction of the pulse signal return.

[0057] In this embodiment, the particles follow gases such as oxygen into the furnace. The particles themselves do not participate in combustion. After the oxygen in the gas comes into contact with the fuel and burns, the particles continue to move under the action of gas pressure. Due to the uneven distribution of fuel and the different temperatures at different locations, the particles that enter the furnace evenly are not evenly distributed above the fuel. Based on the above characteristics, by detecting the position of the particles and determining their excited state, the combustion situation can be simulated and analyzed.

[0058] It should be noted that the particles themselves have a certain mass, and it is precisely because of this mass that they can effectively follow the movement of the airflow. The gas flow velocity varies depending on the position of the particle near the furnace arm. Different gas flow velocities will have a certain impact on the rise and fall of temperature. For the above reasons, this application needs to effectively capture the spatial position of each particle at the current time through relevant equipment or instruments. The ultimate goal of capturing the above spatial position is to infer the current gas flow and temperature distribution in the furnace. Only after the gas flow state in the entire furnace is determined can the specific temperature and other information in the furnace be inferred.

[0059] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, the identifier infers the level of excited states within a certain volume range based on the received returned pulse signals, including:

[0060] The identifier infers the spatial position of the calibrated particles within the corresponding range based on the time interval between the emitted and returned pulse signals, the amount and angle of the returned pulse signals, and the current position of the identifier.

[0061] First, particles exhibit different excited states at different temperatures. By real-time detection of these excited states, the corresponding temperature value can be inferred. Once the temperature is determined, relevant instruments are needed to pinpoint the particle positions. However, for particles to be evenly distributed within the furnace, their mass and volume must be small, as only this design can ensure particle movement with the gas. This presents a problem: due to the small particle size, it becomes difficult to effectively control the position of each particle. Furthermore, the rapid particle movement during combustion places high demands on computational capabilities.

[0062] In order to solve the above problems, this application can identify particles in different excited states and detect the overall excited state of particles in a certain range. The overall state is used as the detection standard to judge the state of each particle. Moreover, a lot of instruments and equipment are required. By integrating the information determined by the acquisition instruments at different positions, the distribution of particles at different heights can be inferred.

[0063] In scientific research and production control, it is often necessary to monitor the thermal reaction process of materials online to characterize the chemical reactions occurring within the materials themselves or between mixed components. For a mature production process, the types of gas components produced are stable under steady operating conditions, and the content of each component is also relatively stable. In such cases, accurate online monitoring can usually be achieved using a custom-designed gas composition analyzer. This custom-designed gas composition analyzer is typically equipped with dedicated detection modules and set measurement ranges based on certain characteristics of different gases, providing accurate and reliable analysis of the components in mixed gases under stable operating conditions.

[0064] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, and based on the feedback from each identifier, the spatial distribution of each calibrated particle in the furnace is simulated, including:

[0065] By changing the specifications of the pulse signal, the pulse signal can detect and cover calibration particles at different distances. The contents determined by the pulse signals under different states are integrated and optimized, and finally the spatial distribution of calibration particles and the level of excited states at different distances are determined.

[0066] Firstly, the furnace contains multiple particles. Different furnace temperatures result in different excited states for these particles. More importantly, the combustion process generates a significant amount of dust and impurities, which inevitably affect particle location determination. Therefore, it is necessary not only to identify the particles but also to determine their excited states and locations. Since particles do not participate in the combustion reaction, they only undergo changes at different temperatures, resulting in different excited states. By identifying particles in different excited states within the furnace, their spatial locations can be determined.

[0067] To achieve the aforementioned technical effects, this application includes installing and fixing identifiers on the side wall of the furnace. The identifier can be understood as a device capable of emitting multiple specific frequency pulse waves towards the particles inside the furnace. The pulse waves emitted by the identifier can directly act on the particles, or only the particles can receive the pulse waves and reflect them to a corresponding degree. By installing identifiers at different heights and angles inside the furnace, and integrating the data determined by identifiers at the same height but different angles, the overall distribution of particles within the furnace cavity and the overall level of excited states in each region can be obtained.

[0068] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, and based on the feedback from each identifier, the spatial distribution of each calibrated particle in the furnace is simulated, including:

[0069] Based on the spatial positions of multiple detectors relative to the furnace, the spatial range that each detector can detect is integrated and filled, and finally a spatial model is simulated when the calibration particles fill the combustion furnace cavity.

[0070] Based on the spatial model and the predicted temperature levels, the spatial temperature distribution of the entire furnace is inferred.

[0071] To explain in more detail, particles in the excited state are difficult to identify amidst a large amount of impurities and fly ash, and the number of particles injected into the furnace needs to be limited. A large number of particles would inevitably affect the air intake and increase costs. For these reasons, the total number of particles needs to be limited while ensuring detection accuracy. The purpose of the identifier is to effectively identify particles in different excited states amidst a large amount of impurities and fly ash. This requires emitting pulse waves that can only be received and reflected by the particles. The identifier determines the overall level and location of the excited state of the particles within a certain range based on the amount and time interval of the returned pulse waves.

[0072] Since particles at different temperatures have different excited states, their absorption and reflection of pulse waves also differ. The absorber infers the temperature of particles within a spatial region based on the absorption and reflection of pulse waves by each particle. The detection range of a single identifier is limited, and the volume of space that a single identifier can detect is also limited. Therefore, a single identifier can only determine the particle temperature and distribution within a specific volume of the furnace.

[0073] By integrating the temperature data determined by multiple identifiers, that is, by superimposing the temperature data determined at different spatial locations, it is possible to infer the temperature of the particles in the entire furnace. Then, based on the correspondence between the excited state and different temperature values, the temperature distribution in the furnace can be determined.

[0074] In some embodiments of the flue gas temperature measurement method in a waste incinerator provided in this application, after inferring the overall temperature distribution inside the furnace based on the determined excited state level, the method further includes:

[0075] Each calibration particle that flows out is recovered using magnetic force, and then the recovered calibration particles are demagnetized and reused.

[0076] The particles can be low-mass metal particles with high melting points. To save costs, they need to be recycled and reused. The particles discharged from the furnace can be magnetized by an exciter. After magnetization, the particles are recycled and then demagnetized for subsequent use.

[0077] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for measuring the temperature of flue gas inside a waste incinerator, characterized in that, include: The required calibration particles are determined based on the type of fuel in the furnace and the state of the combustion reaction. These calibration particles do not participate in the combustion reaction and will be in different excited states at different temperatures. The calibration particles are introduced into the furnace along with the gas. Multiple identifiers identify and determine the excited state level of the calibration particles within the corresponding volume range of the furnace. Based on the feedback from each identifier, the spatial distribution of each calibration particle in the furnace is simulated. Combined with the determined excited state level, the overall temperature distribution in the furnace is inferred.

2. The method for measuring flue gas temperature in a waste incinerator as described in claim 1, characterized in that, The determination of the required calibration particles based on the type of fuel in the furnace and the state of the combustion reaction includes: The calibration particles of appropriate volume and mass are selected based on the velocity and flow rate of the gas entering the furnace.

3. The method for measuring flue gas temperature in a waste incinerator as described in claim 1, characterized in that, The step of allowing the calibration particles to enter the furnace along with the gas includes: The calibration particles are magnetized so that they have the same magnetic properties, which generates a repulsive force, ensuring that the calibration particles are spaced apart.

4. The method for measuring flue gas temperature in a waste incinerator as described in claim 1, characterized in that, The calibration particles do not participate in the combustion reaction and will be in different excited states at different temperatures, including: The calibration particles flow through the burning fuel and continue to move upward with the gas. The calibration particles will be in different excited states depending on the temperature of their surrounding environment.

5. The method for measuring flue gas temperature in a waste incinerator as described in claim 1, characterized in that, The process of identifying and determining the excited state level of the calibration particles within the corresponding volume range inside the furnace using multiple identifiers includes: The identifier sends a pulse signal into the furnace that can only act on the calibration particles; the calibration particles have different sensitivities to the pulse signal depending on their excited state. The identifier infers the level of the excited state within a certain volume range based on the received returned pulse signal, and determines the position of the calibrated particle within the corresponding range.

6. The method for measuring flue gas temperature in a waste incinerator as described in claim 5, characterized in that, The sensitivity of the calibration particles to the pulse signal varies depending on their excited state, including: When the excited states are different, the amount of absorption and reflectivity of the calibrated particles to the pulse signal are different; the identifier infers the level of the excited state based on the time, amount and direction of the pulse signal return.

7. The method for measuring flue gas temperature in a waste incinerator as described in claim 6, characterized in that, The identifier infers the level of the excited state within a certain volume range based on the received returned pulse signal, including: The identifier infers the spatial position of the calibrated particles within the corresponding range based on the time interval between the emission and return of the pulse signal, the amount and angle of the returned pulse signal, and the current position of the identifier.

8. The method for measuring flue gas temperature in a waste incinerator as described in claim 5, characterized in that, The simulation of the spatial distribution of each calibrated particle within the furnace, based on feedback from each of the identifiers, includes: By changing the specifications of the pulse signal, the pulse signal can detect and cover the calibration particles at different distances. The contents determined by the pulse signal in different states are integrated and optimized, and finally the spatial distribution of the calibration particles and the level of the excited state at different distances are determined.

9. The method for measuring flue gas temperature in a waste incinerator as described in claim 7, characterized in that, The simulation of the spatial distribution of each calibrated particle within the furnace, based on feedback from each of the identifiers, includes: Based on the spatial positions of the multiple identifiers relative to the furnace, the spatial range that each identifier can detect is integrated and filled to finally simulate the spatial model when the calibrated particles fill the furnace cavity; Based on the spatial model and the predicted temperature levels, the spatial temperature distribution of the entire furnace is inferred.

10. The method for measuring flue gas temperature in a waste incinerator as described in claim 1, characterized in that, After inferring the overall temperature distribution within the furnace based on the determined excited state levels, the process further includes: The outflowing calibration particles are recovered using magnetic force, and then the recovered calibration particles are demagnetized and reused.

Images