Selective catalytic reduction flue gas heating device
By using a selective catalytic reduction flue gas heating device, which mixes the flue gas from the combustion furnace with the flue gas from the main pipeline of the internal combustion engine, and combined with a data acquisition and control module, the problem of low exhaust temperature of the internal combustion engine is solved, achieving precise control of flue gas temperature and improving SCR efficiency, while extending catalyst life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NANJING SOUTHEAST IND EQUIP CORP
- Filing Date
- 2023-03-03
- Publication Date
- 2026-07-21
AI Technical Summary
In existing technical solutions, the exhaust temperature of the internal combustion engine is lower than the catalytic reduction (SCR) reaction temperature, which requires the flue gas to be heated. Existing methods are complex, costly, or difficult to modify the internal combustion engine structure. Furthermore, the catalyst is prone to generating ABS, which affects its service life and denitrification efficiency.
A selective catalytic reduction flue gas heating device is adopted, which directly generates high-temperature flue gas through combustion in the combustion furnace and mixes it with the flue gas in the main pipeline of the internal combustion engine. The heater controls the flue gas temperature within the optimal reaction range of the catalyst, and the heating power and valve opening are precisely adjusted by data acquisition and control modules.
It achieves precise control of flue gas temperature, reduces ABS formation, extends catalyst life, improves SCR denitrification efficiency, and features a compact structure, low cost, and easy installation and maintenance.
Smart Images
Figure CN115875111B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of temperature control, and in particular to a selective catalytic reduction flue gas heating device. Background Technology
[0002] Currently, there are three main technical solutions for emissions from high-power internal combustion engines: one is to use electric heating coils to heat the flue gas; another is to open holes in the existing flue gas ducts and use high-temperature induced draft fans to guide the flue gas to the combustion furnace burner for heating, and then send the heated flue gas back to the exhaust pipe from the combustion furnace; and the third is to modify the internal combustion engine to increase the exhaust temperature. The disadvantages of using electric heating coils to heat flue gas in Option 1 are: air has a low specific heat capacity and low thermal conductivity, resulting in low heat exchange efficiency and high power consumption. Furthermore, since ship power comes from generator sets, this increases the actual power consumption of the generator sets. Option 2 involves opening holes in the existing flue gas duct and using a high-temperature induced draft fan to guide the flue gas to the combustion chamber burner for heating. The heated flue gas is then sent back to the exhaust pipe. However, this option requires an externally located combustion chamber burner, necessitating a high-temperature fan to guide the exhaust gas from the exhaust pipe to the combustion chamber for heating before sending it back to the main exhaust pipe. This system is complex and requires a large installation space, which is not conducive to a reasonable engine room layout. Option 3 involves modifying the internal combustion engine to increase its exhaust temperature. This option requires the approval of the internal combustion engine manufacturer and necessitates changes to the overall structure of the internal combustion engine and adjustments to the turbocharger's arrangement, making it relatively difficult and risky. This invention aims to solve this problem by proposing a selective catalytic reduction flue gas heating device. Summary of the Invention
[0003] The main objective of this invention is to provide a selective catalytic reduction flue gas heating device. In order to meet the process requirements of selective catalytic reduction (SCR) for marine internal combustion engine emissions, when the exhaust temperature of the marine internal combustion engine is lower than the selective catalytic reduction (SCR) catalytic reaction temperature, the flue gas needs to be heated to bring the flue gas temperature to the optimal reaction temperature of the catalyst, thereby reducing the formation of ABS, extending the service life of the catalyst, and improving the SCR denitrification efficiency.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A selective catalytic reduction (SCR) flue gas heating device includes a main flue gas transmission path and a combustion furnace. The output end of the combustion furnace is inserted into the main flue gas transmission path. A furnace collector and a burner are installed inside the combustion furnace. A control valve is installed at the input end of the main flue gas transmission path, and a main path collector is installed inside the main flue gas transmission path. The heating device also includes a data acquisition system, a data analysis system, a control module, and a heater. The data acquisition system is used to read and classify the data collected by the furnace collector and the main path collector. The data analysis system is used to analyze the collected data, calculate the temperature of the mixed flue gas after mixing the flue gas from the combustion furnace and the main path, calculate the remaining temperature value of the flue gas when it reaches a designated position, compare it with a set temperature threshold, and calculate the operating power of the heater and the opening degree of the control valve. The control module is used to control the operating power of the heater and the opening degree of the control valve based on the calculated control data. The heater is used to heat the transmitted flue gas so that the temperature of the flue gas transmitted to the catalyst is within the optimal reaction temperature range of the catalyst.
[0005] A further improvement of the present invention is that the acquisition system includes a temperature acquisition module, a flue gas data acquisition module, and a heater heating power acquisition module. The temperature acquisition module is used to acquire flue gas temperature data after the flue gas mixing process of the furnace collector and the main circuit collector. The flue gas data acquisition module is used to extract the data acquired by the furnace collector and the main circuit collector and transmit the data to the data analysis system. The heater heating power acquisition module is used to acquire the heating power of the heater.
[0006] A further improvement of the present invention is that the data analysis system includes a temperature analysis module and a temperature calculation module. The temperature analysis module is used to classify the data collected by the temperature acquisition module and the flue gas data acquisition module, and to calculate the average value of various types of data collected by the temperature acquisition module and the flue gas data acquisition module. The temperature calculation module is used to calculate the remaining temperature value of the flue gas when it reaches a specified position based on the average value of various types of data analyzed by the temperature analysis module, and to compare it with a set temperature threshold. The difference between the remaining temperature value and the temperature threshold is calculated to calculate the temperature compensation amount of the heater and the valve opening compensation amount.
[0007] A further improvement of the present invention is that the control module includes a heater power control unit and a flue gas transmission speed control unit. The heater power control unit is used to calculate the compensation power value of the heater by substituting the temperature compensation amount into the calculation. The flue gas transmission speed control unit is used to control the valve opening by the valve opening compensation amount, thereby controlling the flue gas transmission speed.
[0008] A further improvement of the present invention is that the flue gas data acquisition module includes a main flue gas temperature acquisition unit, a main flue gas flow acquisition unit, a combustion furnace flue gas temperature acquisition unit, and a combustion furnace flue gas flow acquisition unit. The main flue gas temperature acquisition unit is used to acquire the real-time temperature of the flue gas transmitted through the main flue gas. The main flue gas flow acquisition unit is used to acquire the real-time transmission flow rate of the main flue gas. The combustion furnace flue gas temperature acquisition unit is used to acquire the temperature value of the flue gas transmitted through the combustion furnace. The combustion furnace flue gas flow acquisition unit is used to acquire the flow rate value of the flue gas transmitted through the combustion furnace.
[0009] A further improvement of the present invention is that the heating device includes a flue gas heating method strategy, which includes the following specific steps: S1. The flue gas data acquisition module uses an array-type temperature acquisition instrument to collect the temperature of the main input flue gas at the output end of the control valve. The sequence of collected main input temperature values is ( ),in In this diagram, T represents the measured temperature value, the superscript j indicates the main input, and the subscript n indicates the nth temperature acquisition probe at the output of the control valve. Thus, the average value of the main input flue gas is calculated as follows: ,in The i-th item in the main input temperature value sequence, the flue gas data acquisition module obtains the main flue gas flow value. Data was collected, and the output flow rate of the combustion furnace flue gas was also collected. The temperature of the flue gas output from the combustion furnace is collected at the output end of the flue gas output pipe using an array-type temperature acquisition instrument. The collected flue gas output temperature sequence is ( ),in In this diagram, T represents the measured temperature value, the superscript l indicates the output of the combustion furnace, and the subscript n indicates the nth temperature acquisition probe. The average value of the flue gas temperature output from the combustion furnace is calculated. , For the i-th term in the flue gas temperature sequence output from the combustion furnace, the real-time heating power of the heater is collected. and set temperature threshold Set the temperature to 300-420℃; S2. Calculate the flow rate and overall temperature of the mixed flue gas. The flow rate of the mixed flue gas is: The overall temperature of the mixed flue gas is: The calculated data is substituted into the data analysis system, and the calculated temperature is substituted into the heat dissipation consumption calculation strategy to obtain the heat dissipation model of the mixed flue gas in the pipe. S3. The temperature calculation module calculates the remaining temperature of the flue gas when it reaches the specified position and compares it with the set temperature threshold. S4. If the remaining temperature value is less than the minimum value of the temperature threshold range, the heater is turned on to heat the flue gas. If the remaining temperature value is within the temperature threshold range, the flue gas is directly transmitted. If the calculated remaining temperature value is greater than the maximum value of the temperature threshold, the opening of the control valve is increased to increase the input flow rate of the main flue gas. S5. The control module controls the heater and valve by calculating the valve opening degree and heater working power data.
[0010] A further improvement of this invention lies in that the heat dissipation consumption calculation strategy in S2 is as follows: A pipe segment of length k is selected in the main pipeline, and the heat loss T of the flue gas during its transmission within the pipe segment is calculated; then the heat dissipation efficiency is... .
[0011] A further improvement of this invention is that, in step S3, the formula for calculating the remaining temperature value of the flue gas when it reaches the designated position is as follows: ,in The length of the main pipeline.
[0012] A further improvement of this invention is that, in step S4, if the remaining temperature value is less than the minimum value of the temperature threshold range, the heater is turned on to heat the flue gas. The formula for calculating the heating power of the heater is as follows: ,in To transfer the specific heat capacity of the flue gas, To transmit the density of the flue gas, For heat transfer efficiency, This is the minimum value within the temperature threshold range.
[0013] A further improvement of this invention is that, if the remaining temperature value calculated in step S4 is greater than the maximum value of the temperature threshold, then the opening of the control valve is increased, thereby increasing the input flow rate of the main flue gas. The formula for calculating the increase in the input flow rate of the main flue gas is as follows: ,in This represents the maximum value within the temperature threshold range.
[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. By setting up a selective catalytic reduction injection pipe directly connected to the inclined combustion furnace, it is used for direct combustion of the burner. The high-temperature flue gas generated by the combustion is mixed with the flue gas in the main pipeline of the internal combustion engine to increase the flue gas temperature of the internal combustion engine. The resulting flue gas heating device has a compact structure, is easy to arrange, has a simple manufacturing process and low cost, is easy to produce and maintain, and can adjust the burner power according to different exhaust pipe diameters, with high thermal efficiency and economic benefits. 2. When the exhaust temperature of the ship's internal combustion engine is lower than the selective catalytic reduction (SCR) reaction temperature, the heating power of the heater is accurately controlled. The heater is used to heat the flue gas, so that the flue gas temperature reaches the optimal reaction temperature of the catalyst. This reduces the formation of ABS, extends the service life of the catalyst, and improves the SCR denitrification efficiency. At the same time, when the flue gas temperature is higher than the maximum temperature of the SCR system, the control module increases the opening of the control valve by controlling the main flue gas input flow, so that the flue gas temperature is always at the optimal reaction temperature of the catalyst. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structural framework of a selective catalytic reduction flue gas heating device according to the present invention.
[0016] Figure 2 This is a schematic diagram of the structure of a selective catalytic reduction flue gas heating device according to the present invention.
[0017] Figure 3 This is a schematic diagram of the flue gas data acquisition module of a selective catalytic reduction flue gas heating device according to the present invention.
[0018] Figure 4 This is a schematic diagram of the flue gas heating method of the control module of the selective catalytic reduction flue gas heating device of the present invention.
[0019] In the diagram: 1. Main flue gas transmission path; 2. Combustion furnace; 3. Furnace collector; 4. Burner; 5. Control valve; 6. Main path collector. Detailed Implementation
[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.
[0021] Example 1 This embodiment uses a selective catalytic reduction (SCR) injection pipe directly connected to an inclined combustion furnace 2 for direct combustion in burner 4. The high-temperature flue gas generated by combustion mixes with the flue gas from the internal combustion engine's main pipeline to increase the flue gas temperature. The resulting flue gas heating device is compact, easy to arrange, has a simple manufacturing process, low cost, and is easy to produce and maintain. The power of burner 4 can be adjusted according to different exhaust pipe diameters, resulting in high thermal efficiency and economic benefits. In selective catalytic reduction (SCR), the reaction temperature determines not only the reaction rate of the reactants but also the activity of the catalyst. Generally, the higher the reaction temperature, the faster the reaction rate and the higher the catalyst activity, thus requiring less reaction space per unit reaction and reducing the reactor volume. Considering the heating of reactants, system control, and the catalyst's suitable temperature range, the SCR system temperature is typically set between 300-420°C, while the flue gas temperature of low-speed engines is generally between 200-250°C.
[0022] The reaction mechanism for the removal of nitrogen oxides by SCR is: 4NO + 4NH3 + O2 → 4N2 + 6H2O 2NO₂ + 4NH₃ + O₂ → 3N₂ + 6H₂O (Main reaction) 6NO2 + 8NH3 → 7N2 + 12H2O When the waste gas to be treated contains sulfur, the following reaction will occur: 2SO2 + O2 → 2SO3 (Side reaction) SO3 + NH3 + H2O → NH4HSO4 (ABS) The second side reaction occurs in the exhaust gas and does not take place on the catalyst surface. Among the many components of the exhaust gas, the gaseous components participating in the SCR reaction are limited to NO, NO2, NH3, O2, SO2, and SO3.
[0023] In the side reactions, if the exhaust gas temperature is below the dew point of ABS, ABS will precipitate from the exhaust gas and condense into a viscous liquid. On the one hand, the precipitated ABS can adhere to the catalyst surface, covering the active sites and thus reducing the catalyst's activity; on the other hand, it can also adhere to the internal components of the SCR reactor and downstream equipment, causing system corrosion. High concentrations of SOX promote ABS formation; therefore, the higher the SOX concentration, the higher the minimum allowable continuous operating temperature of the system. Therefore, the dew point of ABS on the catalyst can be considered the minimum allowable operating temperature of the SCR system.
[0024] Therefore, this embodiment proposes improvements on the existing technology, such as... Figures 1-4As shown, a selective catalytic reduction flue gas heating device includes a main flue gas transmission path 1 and a combustion furnace 2. The output end of the combustion furnace 2 is inserted into the main flue gas transmission path 1. A furnace collector 3 and a burner 4 are installed inside the combustion furnace 2. A control valve 5 is installed at the input end of the main flue gas transmission path 1. A main path collector 6 is installed inside the main flue gas transmission path 1. The heating device also includes a data acquisition system, a data analysis system, a control module, and a heater. The data acquisition system is used to read and classify the data collected by the furnace collector 3 and the main path collector 6. The data analysis system is used to analyze the collected data, calculate the temperature of the mixed flue gas after mixing the flue gas from the combustion furnace 2 and the main path, calculate the remaining temperature value of the flue gas when it reaches a designated position, compare it with a set temperature threshold, and calculate the working power of the heater and the opening degree of the control valve 5. The control module is used to control the working power of the heater and the opening degree of the control valve 5 according to the calculated control data. The heater is used to heat the transmitted flue gas so that the temperature of the flue gas transmitted to the catalyst is within the optimal reaction temperature range of the catalyst. In this embodiment, the acquisition system includes a temperature acquisition module, a flue gas data acquisition module, and a heater heating power acquisition module. The temperature acquisition module is used to acquire flue gas temperature data after the flue gas mixing process of furnace collector 3 and main circuit collector 6. The flue gas data acquisition module is used to extract the data acquired by furnace collector 3 and main circuit collector 6 and transmit the data to the data analysis system. The heater heating power acquisition module is used to acquire the heating power of the heater. In this embodiment, the data analysis system includes a temperature analysis module and a temperature calculation module. The temperature analysis module is used to classify the data collected by the temperature acquisition module and the flue gas data acquisition module, and to calculate the average value of various types of data collected by the temperature acquisition module and the flue gas data acquisition module. The temperature calculation module is used to calculate the remaining temperature value of the flue gas when it reaches the specified position based on the average value of various types of data analyzed by the temperature analysis module, and compare it with the set temperature threshold. The difference between the remaining temperature value and the temperature threshold is calculated to calculate the temperature compensation amount of the heater and the valve opening compensation amount. In this embodiment, the control module includes a heater power control unit and a flue gas transmission speed control unit. The heater power control unit is used to calculate the compensated power value of the heater by substituting the temperature compensation amount into it. The flue gas transmission speed control unit is used to control the opening of valve 5 by the valve opening compensation amount, thereby controlling the transmission speed of the flue gas. The flue gas data acquisition module includes a main flue gas temperature acquisition unit, a main flue gas flow acquisition unit, a combustion furnace 2 flue gas temperature acquisition unit, and a combustion furnace 2 flue gas flow acquisition unit. The main flue gas temperature acquisition unit is used to acquire the real-time temperature of the flue gas transmitted through the main line. The main flue gas flow acquisition unit is used to acquire the real-time transmission flow rate of the flue gas through the main line. The combustion furnace 2 flue gas temperature acquisition unit is used to acquire the temperature value of the flue gas transmitted through the combustion furnace 2. The combustion furnace 2 flue gas flow acquisition unit is used to acquire the flow rate value of the flue gas transmitted through the combustion furnace 2.
[0025] This embodiment enables the following: by setting a selective catalytic reduction injection pipe side directly connected to the inclined combustion furnace 2 for direct combustion in the burner 4, the high-temperature flue gas generated by combustion is mixed with the flue gas in the main pipeline of the internal combustion engine to increase the flue gas temperature of the internal combustion engine. The resulting flue gas heating device has a compact structure, is easy to arrange, has a simple manufacturing process and low cost, is easy to produce and maintain, and the power of the burner 4 can be adjusted according to different exhaust pipe diameters, resulting in high thermal efficiency and economic benefits.
[0026] Example 2 Example 2 is mainly used to improve upon Example 1 by accurately controlling the heating power of the heater when the exhaust temperature of the ship's internal combustion engine is lower than the selective catalytic reduction (SCR) reaction temperature. The heater heats the flue gas to bring it to the optimal reaction temperature of the catalyst, reducing ABS formation, extending catalyst lifespan, and improving SCR denitrification efficiency. Simultaneously, when the flue gas temperature exceeds the maximum temperature of the SCR system, the control module increases the opening of control valve 5, thereby increasing the main flue gas input flow rate to ensure the flue gas temperature remains at the optimal reaction temperature of the catalyst. Specifically, the scheme is as follows: Figures 1-4As shown, a selective catalytic reduction flue gas heating device includes a main flue gas transmission path 1 and a combustion furnace 2. The output end of the combustion furnace 2 is inserted into the main flue gas transmission path 1. A furnace collector 3 and a burner 4 are installed inside the combustion furnace 2. A control valve 5 is installed at the input end of the main flue gas transmission path 1. A main path collector 6 is installed inside the main flue gas transmission path 1. The heating device also includes a data acquisition system, a data analysis system, a control module, and a heater. The data acquisition system is used to read and classify the data collected by the furnace collector 3 and the main path collector 6. The data analysis system is used to analyze the collected data, calculate the temperature of the mixed flue gas after mixing the flue gas from the combustion furnace 2 and the main path, calculate the remaining temperature value of the flue gas when it reaches a designated position, compare it with a set temperature threshold, and calculate the working power of the heater and the opening degree of the control valve 5. The control module is used to control the working power of the heater and the opening degree of the control valve 5 according to the calculated control data. The heater is used to heat the transmitted flue gas so that the temperature of the flue gas transmitted to the catalyst is within the optimal reaction temperature range of the catalyst. In this embodiment, the acquisition system includes a temperature acquisition module, a flue gas data acquisition module, and a heater heating power acquisition module. The temperature acquisition module is used to acquire flue gas temperature data after the flue gas mixing process of furnace collector 3 and main circuit collector 6. The flue gas data acquisition module is used to extract the data acquired by furnace collector 3 and main circuit collector 6 and transmit the data to the data analysis system. The heater heating power acquisition module is used to acquire the heating power of the heater. In this embodiment, the data analysis system includes a temperature analysis module and a temperature calculation module. The temperature analysis module is used to classify the data collected by the temperature acquisition module and the flue gas data acquisition module, and to calculate the average value of various types of data collected by the temperature acquisition module and the flue gas data acquisition module. The temperature calculation module is used to calculate the remaining temperature value of the flue gas when it reaches the specified position based on the average value of various types of data analyzed by the temperature analysis module, and compare it with the set temperature threshold. The difference between the remaining temperature value and the temperature threshold is calculated to calculate the temperature compensation amount of the heater and the valve opening compensation amount. In this embodiment, the control module includes a heater power control unit, which calculates the compensated power value of the heater by substituting the temperature compensation amount into the calculation. The flue gas transmission speed control unit controls the opening of valve 5 by the valve opening compensation amount, thereby controlling the transmission speed of the flue gas. The flue gas data acquisition module includes a main flue gas temperature acquisition unit, a main flue gas flow acquisition unit, a combustion furnace 2 flue gas temperature acquisition unit, and a combustion furnace 2 flue gas flow acquisition unit. The main flue gas temperature acquisition unit is used to acquire the real-time temperature of the main flue gas, the main flue gas flow acquisition unit is used to acquire the real-time transmission flow rate of the main flue gas, the combustion furnace 2 flue gas temperature acquisition unit is used to acquire the temperature value of the flue gas transmitted in the combustion furnace 2, and the combustion furnace 2 flue gas flow acquisition unit is used to acquire the flow rate value of the flue gas transmitted in the combustion furnace 2. In this embodiment, the heating device includes a flue gas heating method strategy, which includes the following specific steps: S1. The flue gas data acquisition module uses an array-type temperature acquisition instrument to acquire the main input flue gas temperature at the output end of control valve 5. The acquired main input temperature value sequence is ( ),in In this diagram, T represents the measured temperature value, the superscript j indicates the main input, and the subscript n indicates the nth temperature acquisition probe on the output terminal of control valve 5. Thus, the average value of the main input flue gas is calculated as follows: ,in The i-th item in the main input temperature value sequence, the flue gas data acquisition module obtains the main flue gas flow value. Data was collected, and the flue gas output flow rate of combustion furnace 2 was also collected. The temperature of the flue gas output from combustion furnace 2 is collected at the output end of the flue gas output pipe using an array-type temperature acquisition instrument. The collected flue gas output temperature sequence of combustion furnace 2 is as follows: ),in In this diagram, T represents the measured temperature value, the superscript l indicates the output of combustion furnace 2, and the subscript n indicates the nth temperature acquisition probe. The average value of the flue gas temperature output from combustion furnace 2 is calculated. , For the i-th term in the output flue gas temperature sequence of combustion furnace 2, the real-time heating power of the heater is collected. and set temperature threshold Set the temperature to 300-420℃; S2. Calculate the flow rate and overall temperature of the mixed flue gas. The flow rate of the mixed flue gas is: The overall temperature of the mixed flue gas is: The calculated data is substituted into the data analysis system, and the calculated temperature is substituted into the heat dissipation consumption calculation strategy to obtain the heat dissipation model of the mixed flue gas in the pipe. S3. The temperature calculation module calculates the remaining temperature of the flue gas when it reaches the specified position and compares it with the set temperature threshold. S4. If the remaining temperature value is less than the minimum value of the temperature threshold range, the heater is turned on to heat the flue gas. If the remaining temperature value is within the temperature threshold range, the flue gas is directly transmitted. If the calculated remaining temperature value is greater than the maximum value of the temperature threshold, the opening of the control valve 5 is increased to increase the input flow rate of the main flue gas. S5. The control module controls the heater and valve 5 by calculating the valve opening and heater power data. In this embodiment, the heat dissipation consumption calculation strategy in S2 is as follows: Take a pipe segment of length k in the main pipeline, calculate the heat loss T of the flue gas transmitted within the pipe segment, and then the heat dissipation efficiency is... In S3, the formula for calculating the remaining temperature of the flue gas when it reaches the specified location is as follows: ,in The length of the main pipeline; if the remaining temperature value in S4 is less than the minimum value of the temperature threshold range, then the heater is turned on to heat the flue gas. The formula for calculating the heating power of the heater is: ,in To transfer the specific heat capacity of the flue gas, To transmit the density of the flue gas, For heat transfer efficiency, The minimum value of the temperature threshold range; if the remaining temperature value calculated in S4 is greater than the maximum value of the temperature threshold, then the opening of control valve 5 is increased to increase the input flow rate of the main flue gas. The formula for calculating the increase in the input flow rate of the main flue gas is: ,in This represents the maximum value within the temperature threshold range.
[0027] This embodiment enables the following: when the exhaust temperature of the ship's internal combustion engine is lower than the selective catalytic reduction (SCR) reaction temperature, the heating power of the heater is accurately controlled, and the heater is used to heat the flue gas so that the flue gas temperature reaches the optimal reaction temperature of the catalyst. This reduces the formation of ABS, extends the service life of the catalyst, and improves the SCR denitrification efficiency. At the same time, when the flue gas temperature is higher than the maximum temperature of the SCR system, the control module increases the opening of the control valve 5, thereby increasing the input flow of the main flue gas, so that the flue gas temperature is always at the optimal reaction temperature of the catalyst.
Claims
1. A selective catalytic reduction flue gas heating device, characterized in that... The device includes a main flue gas transmission path (1) and a combustion furnace (2). The output end of the combustion furnace (2) is inserted into the main flue gas transmission path (1). A furnace collector (3) and a burner (4) are installed inside the combustion furnace (2). A control valve (5) is installed at the input end of the main flue gas transmission path (1). A main path collector (6) is installed inside the main flue gas transmission path (1). The heating device also includes a data acquisition system, a data analysis system, a control module, and a heater. The data acquisition system is used to read and classify the data collected by the furnace collector (3) and the main path collector (6). The data analysis system is used to analyze the collected data, calculate the temperature of the mixed flue gas after the combustion furnace (2) and the main flue gas are mixed, calculate the remaining temperature value of the flue gas when it reaches the designated position, compare it with the set temperature threshold, and calculate the working power of the heater and the opening degree of the control valve (5). The control module is used to control the working power of the heater and the opening degree of the control valve (5) according to the calculated control data. The heater is used to heat the transmitted flue gas so that the temperature of the flue gas transmitted to the catalyst is in the optimal reaction temperature range of the catalyst. The data analysis system includes a temperature analysis module and a temperature calculation module. The temperature analysis module is used to classify the data collected by the temperature acquisition module and the flue gas data acquisition module, and to calculate the average value of various types of data collected by the temperature acquisition module and the flue gas data acquisition module. The control module includes a heater power control unit and a flue gas transmission speed control unit. The heater power control unit is used to calculate the compensation power value of the heater by substituting the temperature compensation amount into it. The flue gas transmission speed control unit is used to control the opening of the valve (5) by the valve opening compensation amount, thereby controlling the transmission speed of the flue gas. The temperature calculation module is used to calculate the remaining temperature value of the flue gas when it reaches a specified position based on the average value of various types of data analyzed by the temperature analysis module, and compare it with the set temperature threshold. The difference between the remaining temperature value and the temperature threshold is calculated to calculate the temperature compensation amount of the heater and the valve opening compensation amount.
2. The selective catalytic reduction flue gas heating device according to claim 1, characterized in that: The acquisition system includes a temperature acquisition module, a flue gas data acquisition module, and a heater heating power acquisition module. The temperature acquisition module is used to acquire flue gas temperature data after the flue gas mixing process of the furnace collector (3) and the main circuit collector (6).
3. The selective catalytic reduction flue gas heating device according to claim 2, characterized in that: The flue gas data acquisition module includes a main flue gas temperature acquisition unit, a main flue gas flow acquisition unit, a combustion furnace (2) flue gas temperature acquisition unit, and a combustion furnace (2) flue gas flow acquisition unit. The main flue gas temperature acquisition unit is used to acquire the real-time temperature of the flue gas transmitted through the main line.
4. The selective catalytic reduction flue gas heating device according to claim 3, characterized in that: The main flue gas flow acquisition unit is used to collect the transmission flow of the main flue gas in real time. The combustion furnace (2) flue gas temperature acquisition unit is used to collect the flue gas temperature value transmitted by the combustion furnace (2). The combustion furnace (2) flue gas flow acquisition unit is used to collect the flue gas flow value transmitted by the combustion furnace (2).
5. The selective catalytic reduction flue gas heating device according to claim 4, characterized in that: The flue gas data acquisition module is used to extract the data collected by the furnace collector (3) and the main circuit collector (6) and transmit the data to the data analysis system. The heater heating power acquisition module is used to collect the heating power of the heater.