Operation control method of boron diffusion exhaust heat recovery system
By analyzing the parameters of the exhaust duct and the flow and temperature of the exhaust gas, the threshold buffer zone of the boron expansion exhaust heat recovery system was adaptively set, which solved the problem of frequent bypass valve switching and improved the rationality of system operation control and component life.
Patent Information
- Application Number
- CN202511619313.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-06
- Publication Date
- 2026-01-09
Smart Images
Figure CN121297566A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of energy-saving technology, specifically to an operation control method for a boron exhaust heat recovery system. Background Technology
[0002] The boron diffusion exhaust heat recovery system is a device specifically designed to recover the heat energy from the high-temperature waste gas generated during the "boron diffusion" process in semiconductor manufacturing. In semiconductor manufacturing, boron is injected into silicon wafers as a dopant at high temperatures to alter their electrical properties. This process takes place in a specially designed diffusion furnace, and the resulting waste gas is extremely hot and contains acidic, toxic, and corrosive components. To reduce environmental pollution and facilitate subsequent reactions, the high-temperature, harmful gases discharged from the diffusion furnace must be promptly transported and subjected to heat exchange. This process recovers waste heat while simultaneously reducing the waste gas temperature, thereby improving waste gas treatment efficiency.
[0003] Existing boron-based exhaust heat recovery systems primarily employ a fixed threshold control method. This involves setting a pre-defined temperature threshold. When the exhaust temperature exceeds this threshold, the system prioritizes airflow through the heat recovery unit for heat exchange, maximizing heat recovery. Conversely, when the exhaust temperature falls below the threshold or is unsuitable for heat recovery, the system automatically opens a bypass valve to prevent condensation and corrosion. However, fixed threshold control often presents the following technical challenges: When the exhaust temperature fluctuates slightly around the threshold, the system often triggers the switching action of the bypass valve, which often accelerates the wear of the seals, resulting in poor rationality of the operation control of the boron expansion exhaust heat recovery system. Summary of the Invention
[0004] To address the technical problem of poor operational control in boron exhaust heat recovery systems, this invention proposes an operational control method for boron exhaust heat recovery systems.
[0005] In a first aspect, the present invention provides an operation control method for a boron exhaust air heat recovery system, the method comprising: Based on the pre-obtained cross-sectional area and length of the exhaust duct included in the boron expansion exhaust heat recovery system, as well as the exhaust gas flow rate, exhaust duct inlet temperature and exhaust duct outlet temperature of the boron expansion exhaust heat recovery system in the current time period, the temperature lag prediction value corresponding to the current moment is determined, where the current moment is the end moment of the current time period. Based on the pre-acquired temperature lag prediction values for all times within the preset window period corresponding to the current time, the buffer zone demand index corresponding to the current time is determined. Similarly, the buffer zone demand index corresponding to each time is determined. If the buffer demand index at the current moment is greater than or equal to the preset demand threshold, then the demand-specific index at the current moment is determined based on the buffer demand index at all moments within the preset window period corresponding to the current moment. Based on the pre-acquired core heat exchanger surface temperature and exhaust gas flow rate within a preset window period, as well as the demand-specific indicators corresponding to the current moment, the threshold buffer zone corresponding to the current moment is adaptively set, and the operation control is performed based on the temperature lag prediction value and the threshold buffer zone.
[0006] In conjunction with the first aspect above, in one possible implementation, determining the temperature lag prediction value corresponding to the current moment based on the pre-acquired cross-sectional area and length of the exhaust duct included in the boron expansion exhaust heat recovery system, and the exhaust gas flow rate, exhaust duct inlet temperature, and exhaust duct outlet temperature of the boron expansion exhaust heat recovery system in the current time period includes: Based on the average value of all waste gas flow rates within the current time period, as well as the cross-sectional area and length of the exhaust duct, determine the transmission delay representative time index corresponding to the current moment; Based on the average inlet temperature of all exhaust ducts during the current time period and the average outlet temperature of all exhaust ducts during the current time period, determine the temperature difference representative index corresponding to the current moment. The ratio between the temperature difference representative index corresponding to the current moment and the transmission delay representative time index is determined as the exhaust gas temperature loss coefficient corresponding to the current moment. Based on the variance of all exhaust gas flow rates within the current time period, and the absolute value of the difference between the mean of all exhaust gas flow rates within the current time period and the exhaust gas flow rate at the current moment, the target confidence factor corresponding to the current moment is determined. Based on the exhaust gas temperature loss coefficient and target confidence factor at the current moment, and the exhaust duct inlet temperature at the current moment, determine the temperature lag prediction value at the current moment.
[0007] In conjunction with the first aspect above, in one possible implementation, determining the transmission delay representative time index corresponding to the current moment based on the average of all exhaust gas flow rates within the current time period, and the cross-sectional area and length of the exhaust duct, includes: The ratio between the average value of all waste gas flow rates within the current time period and the cross-sectional area of the exhaust duct is determined as the representative flow velocity index corresponding to the current moment. The ratio between the length of the exhaust duct and the flow velocity representative index corresponding to the current moment is determined as the transmission delay representative time index corresponding to the current moment.
[0008] In conjunction with the first aspect above, in one possible implementation, determining the buffer zone demand index corresponding to the current moment based on the pre-acquired temperature lag prediction values for all moments within a preset window period corresponding to the current moment includes: The intensity of temperature fluctuation at the current moment is determined based on the variance and frequency of change of the temperature lag prediction values at all times within the preset window period corresponding to the current moment. Based on the difference between the preset control threshold and the temperature lag prediction value corresponding to the current moment, as well as the temperature fluctuation intensity corresponding to the current moment, the buffer demand index corresponding to the current moment is determined.
[0009] In conjunction with the first aspect above, in one possible implementation, determining the demand-specific index corresponding to the current moment based on the buffer inter-time demand indexes corresponding to all moments within the preset window period corresponding to the current moment includes: Based on the difference between the inter-buffer demand index corresponding to the current time and the inter-buffer demand index corresponding to each time within the preset window period corresponding to the current time, the demand specificity index corresponding to the current time is determined.
[0010] In conjunction with the first aspect above, in one possible implementation, the adaptive setting of the threshold buffer interval corresponding to the current moment based on the pre-acquired core heat exchange surface temperature and exhaust gas flow rate within a preset window period, and the demand-specific indicators corresponding to the current moment, includes: If the demand-specific index corresponding to the current moment is less than or equal to the preset specific threshold, then the average temperature of all heat exchanger core heat exchange surfaces within the preset window period corresponding to each moment is determined as the representative temperature of the heat exchange surface corresponding to each moment. Based on the difference between the representative temperature of the heat exchange surface at the next time step and the representative temperature of the heat exchange surface at the previous time step within the preset window period corresponding to the current time step, determine the characteristic value of the heat exchanger temperature change at each time step within the preset window period corresponding to the current time step. Based on the characteristic values of heat exchanger temperature change at all times within the preset window period corresponding to the current time, and the exhaust gas flow rate within the preset window period, the threshold buffer zone corresponding to the current time is adaptively set.
[0011] In conjunction with the first aspect above, in one possible implementation, the step of adaptively setting the threshold buffer interval corresponding to the current moment based on the characteristic values of heat exchanger temperature changes at all times within the preset window period corresponding to the current moment, and the exhaust gas flow rate within the preset window period, includes: The airflow stability at the current moment is determined based on the exhaust gas flow rate within the preset window period corresponding to the current moment. The heat exchanger temperature stability at the current moment is determined based on the characteristic values of heat exchanger temperature change at all times within the preset window period corresponding to the current moment. The product of the airflow stability and the heat exchanger temperature stability at the current moment is determined as the heat recovery stability coefficient at the current moment. Based on the heat recovery stability coefficient at the current moment, set the threshold buffer for the current moment.
[0012] In conjunction with the first aspect above, in one possible implementation, determining the airflow stability corresponding to the current moment based on the exhaust gas flow rate within a preset window period corresponding to the current moment includes: The resistance of the exhaust gas entering the heat recovery device within the preset window period corresponding to the current time is obtained to form a target resistance sequence; The airflow stability at the current moment is determined based on the variance of the target resistance sequence and the standard deviation of the exhaust gas flow rate within the preset window period corresponding to the current moment.
[0013] In conjunction with the first aspect above, in one possible implementation, determining the heat exchanger temperature stability at the current moment based on the characteristic values of heat exchanger temperature changes at all times within a preset window period corresponding to the current moment includes: The temperature stability of the heat exchanger at the current moment is determined based on the variance of the characteristic values of the heat exchanger temperature change at all times within the preset window period corresponding to the current moment.
[0014] In conjunction with the first aspect described above, in one possible implementation, the method further includes: If the demand-specific index corresponding to the current moment is greater than the preset specific threshold, then the bypass valve is opened.
[0015] Secondly, the present invention provides an operation control system for a boron exhaust air heat recovery system, the system comprising: The temperature lag prediction value determination module is used to determine the temperature lag prediction value corresponding to the current moment based on the cross-sectional area and length of the exhaust duct included in the boron expansion exhaust heat recovery system, as well as the exhaust gas flow rate, exhaust duct inlet temperature and exhaust duct outlet temperature of the boron expansion exhaust heat recovery system in the current time period. The current moment is the end moment of the current time period. The buffer zone demand index determination module is used to determine the buffer zone demand index corresponding to the current time based on the temperature lag prediction values of all times within the preset window period corresponding to the current time. Similarly, it determines the buffer zone demand index corresponding to each time. The demand-specific index determination module is used to determine the demand-specific index corresponding to the current time based on the inter-buffer demand index corresponding to all times within the preset window period corresponding to the current time if the inter-buffer demand index corresponding to the current time is greater than or equal to the preset demand threshold. The interval setting and operation control module is used to adaptively set the threshold buffer interval corresponding to the current moment based on the temperature of the core heat exchange surface of the heat exchanger and the exhaust gas flow rate within the preset window period, as well as the demand-specific indicators corresponding to the current moment, and to perform operation control based on the temperature lag prediction value and the threshold buffer interval.
[0016] Thirdly, a server is provided, including a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, causing the device to perform the methods of the first aspect or any possible implementation thereof.
[0017] Fourthly, a computer program product is provided, comprising: computer program code, which, when run on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof.
[0018] Fifthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof.
[0019] The present invention has the following beneficial effects: This invention analyzes the cross-sectional area and length of the exhaust duct, as well as the exhaust gas flow rate, exhaust duct inlet temperature, exhaust duct outlet temperature, and core heat exchanger surface temperature. It quantifies the temperature lag prediction value, buffer zone demand index, and demand-specific index, thereby adaptively setting the threshold buffer zone corresponding to the current moment. Based on the temperature lag prediction value and the threshold buffer zone, the invention performs operational control. To a certain extent, this avoids frequent switching of the bypass valve when the exhaust temperature fluctuates slightly near the threshold, reducing wear on valve seals. This improves the rationality of the operation control of the boron expansion exhaust heat recovery system and, to a certain extent, avoids condensation corrosion caused by low-temperature exhaust gas entering the heat recovery unit, extending the service life of core components such as bypass valves and heat exchangers. Attached Figure Description
[0020] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, 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.
[0021] Figure 1 This is a flowchart of an operation control method for a boron exhaust air heat recovery system according to the present invention; Figure 2 This is a schematic diagram of the composition and structure of the operation control system of a boron exhaust air heat recovery system according to the present invention; Figure 3 This is a schematic diagram of the structure of a computer device according to the present invention. Detailed Implementation
[0022] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the specific implementation methods, structures, features, and effects of the technical solution proposed according to the present invention are described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.
[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0024] refer to Figure 1 The flowchart illustrates some embodiments of an operation control method for a boron exhaust air heat recovery system according to the present invention. The operation control method for the boron exhaust air heat recovery system includes the following steps: Step S1: Based on the pre-obtained cross-sectional area and length of the exhaust duct included in the boron expansion exhaust heat recovery system, as well as the exhaust gas flow rate, exhaust duct inlet temperature and exhaust duct outlet temperature of the boron expansion exhaust heat recovery system in the current time period, determine the temperature lag prediction value corresponding to the current moment.
[0025] The boron diffusion exhaust heat recovery system is a device specifically designed to recover the heat energy from the high-temperature waste gas generated during the "boron diffusion" process in semiconductor manufacturing. The current time can be the end time of the current time period, which can be one month in length. The flow rate of the waste gas in the duct can be monitored in real time by a flow sensor installed in the middle of the duct. The temperature at the duct inlet can be collected in real time by a temperature sensor installed at the duct inlet, and recorded as the duct inlet temperature. The temperature at the duct outlet can be collected in real time by a temperature sensor installed at the duct outlet, and recorded as the duct outlet temperature. The data acquisition frequency is 1Hz. The temperature lag prediction value can be the predicted duct outlet temperature at the next moment.
[0026] As an example, this step may include the following steps: The first step, based on the average exhaust gas flow rate within the current time period, and the cross-sectional area and length of the exhaust duct, determines the representative time index of the transmission delay corresponding to the current moment, which may include the following sub-steps: The first sub-step is to determine the ratio between the average value of all waste gas flow rates within the current time period and the cross-sectional area of the exhaust duct as the representative flow velocity index corresponding to the current moment.
[0027] The second sub-step is to determine the ratio between the length of the exhaust duct and the flow velocity representative index corresponding to the current moment as the transmission delay representative time index corresponding to the current moment.
[0028] For example, the formula for determining the transmission delay corresponding to the current moment as a time index can be: ; ; Where T is the transmission delay time index corresponding to the current moment, which can characterize the average transmission delay time of the exhaust gas being transported in the exhaust duct. d is the length of the exhaust duct. v is the flow velocity index corresponding to the current moment, which can characterize the average flow velocity of the exhaust gas in the duct at this stage. L is the average flow rate of all exhaust gases in the current time period. S is the cross-sectional area of the exhaust duct.
[0029] The second step is to determine the representative temperature difference index corresponding to the current moment based on the average inlet temperature of all exhaust ducts and the average outlet temperature of all exhaust ducts during the current time period.
[0030] For example, the formula for determining the representative index of the temperature difference at the current moment can be: ; in, It is a representative index of the temperature difference at the current moment, which can characterize the average temperature decay rate during the exhaust gas transportation process. It is the average inlet temperature of all exhaust ducts within the current time period. It is the average temperature of all exhaust duct outlets within the current time period.
[0031] The third step is to determine the ratio between the temperature difference representative index corresponding to the current moment and the transmission delay representative time index as the exhaust gas temperature loss coefficient corresponding to the current moment.
[0032] For example, the formula for determining the exhaust gas temperature loss coefficient at the current moment can be: ; in, It is the exhaust gas temperature loss coefficient corresponding to the current moment, which can characterize the temperature decay within a unit transmission delay time. The larger the value, the greater the degree of exhaust gas temperature loss during transmission. T represents the temperature difference at the current moment. T represents the transmission delay at the current moment.
[0033] The fourth step is to determine the target confidence factor corresponding to the current time based on the variance of all exhaust gas flow rates within the current time period, and the absolute value of the difference between the mean of all exhaust gas flow rates within the current time period and the exhaust gas flow rate at the current time.
[0034] For example, the formula for determining the target confidence factor at the current moment can be: ; in, It is the target credibility factor corresponding to the current moment. It is an exponential function with the natural constant as its base. It represents the variance of all exhaust gas flow rates within the current time period. It is an absolute value function. DL is the exhaust gas flow rate at the current moment. L is the average exhaust gas flow rate over the current time period.
[0035] It should be noted that, in practice, the closer the real-time flow rate of the exhaust duct is to the average flow rate, and the more stable the flow rate data, the more accurate the predicted exhaust gas temperature loss coefficient tends to be; that is, the more stable the prediction result is. Therefore, Can characterize The credibility of this.
[0036] Fifth, based on the exhaust gas temperature loss coefficient and target confidence factor corresponding to the current moment, and the exhaust duct inlet temperature at the current moment, determine the temperature lag prediction value corresponding to the current moment.
[0037] For example, the formula for determining the temperature lag prediction value at the current moment can be: ; ; in, It is the temperature lag prediction value corresponding to the current moment. It is the inlet temperature of the exhaust duct at the current moment. This represents the temperature difference at the current moment. R is the temperature loss control factor, and its value range can be [...]. , ]. It is a pre-set function value range control factor greater than 0, which can be set according to the actual scenario, and can be 0.3. It is a normalization function. It is the target credibility factor corresponding to the current moment. It is the exhaust gas temperature loss coefficient at the current moment.
[0038] It should be noted that, It can characterize the temperature decay per unit transmission delay time. The larger the value, the greater the temperature loss of the exhaust gas during transmission. Can characterize The reliability of the data. A larger R value generally indicates a greater temperature loss of the exhaust gas during the current transmission process, and a higher degree to which the outlet temperature of the exhaust duct will be lower than the inlet temperature at the current moment. Therefore, It can represent the predicted value of the exhaust duct outlet temperature at the next moment. In practice, when the exhaust duct outlet temperature is higher, it is often necessary to prioritize guiding the airflow through the heat recovery device to exchange heat and maximize heat recovery. Conversely, when the exhaust duct outlet temperature is lower, it is often necessary to open the bypass ventilation valve to avoid problems such as condensation and corrosion.
[0039] Step S2: Based on the pre-acquired temperature lag prediction values for all times within the preset window period corresponding to the current time, determine the buffer zone demand index corresponding to the current time. Similarly, determine the buffer zone demand index corresponding to each time.
[0040] The preset window period can be a pre-set time period, with a duration of 3 minutes. The current time can be the end time of its corresponding preset window period.
[0041] It should be noted that the methods for obtaining the temperature lag prediction values at different times can be the same as those for obtaining the temperature lag prediction values at the current time, and will not be repeated here.
[0042] As an example, this step may include the following steps: The first step is to determine the intensity of temperature fluctuation at the current moment based on the variance and frequency of change of the temperature lag prediction values at all times within the preset window period corresponding to the current moment.
[0043] The method for obtaining the change frequency of the temperature lag prediction values corresponding to all times within the preset window period corresponding to the current time can be as follows: construct a predicted temperature sequence from the temperature lag prediction values corresponding to all times within the preset window period corresponding to the current time, and determine the difference between each adjacent temperature lag prediction value in the predicted temperature sequence as the target difference value. Select non-zero target differences from all target differences as reference differences, and determine the number of reference differences as the change frequency of the temperature lag prediction values corresponding to all times within the preset window period corresponding to the current time.
[0044] For example, the formula for determining the intensity of temperature fluctuation at the current moment can be: ; Where Q is the intensity of temperature fluctuation at the current moment. The larger the value, the greater the degree of temperature fluctuation at the current moment. is the variance of the lag-predicted temperature values at all times within the preset window period corresponding to the current time. f is the frequency of change of the lag-predicted temperature values at all times within the preset window period corresponding to the current time.
[0045] The second step is to determine the buffer zone demand index corresponding to the current moment based on the difference between the preset control threshold and the temperature lag prediction value corresponding to the current moment, as well as the temperature fluctuation intensity corresponding to the current moment.
[0046] The preset control threshold can be a pre-set temperature threshold used to control the switching of the bypass valve. It can be set by human experience or it can be a threshold in an existing fixed threshold control method.
[0047] For example, the formula for determining the buffer demand index at the current moment can be: ; in, It is the buffer demand indicator corresponding to the current moment. It is a normalization function. It is an absolute value function. It is the temperature lag prediction value corresponding to the current moment. It is a preset control threshold. It is a pre-set factor greater than 0, mainly used to prevent the denominator from being 0, and it can be 0.0001. Q is the intensity of the temperature fluctuation at the current moment.
[0048] It should be noted that when The smaller the value, the closer the predicted temperature lag is to the preset control threshold, and the closer the predicted exhaust temperature for the next moment is to the preset control threshold. Q represents the intensity of the temperature fluctuation at the current moment; a larger value generally indicates a greater degree of temperature fluctuation at that moment. Therefore, when... A higher value usually indicates that the predicted exhaust temperature for the next moment is closer to the preset control threshold, and that the temperature fluctuation at the current moment is greater; it also usually indicates that the control threshold needs to be adjusted more to avoid frequent on / off adjustments.
[0049] Step S3: If the inter-buffer demand index corresponding to the current time is greater than or equal to the preset demand threshold, then determine the demand-specific index corresponding to the current time based on the inter-buffer demand index corresponding to all times within the preset window period corresponding to the current time.
[0050] The preset demand threshold can be a pre-set threshold that can be adaptively set based on the actual scenario. For example, the preset demand threshold can be set to 0.4. In practice, when the current buffer zone demand index is less than the preset demand threshold, it is often unnecessary to set a threshold buffer zone. When the current buffer zone demand index is greater than or equal to the preset demand threshold, it is highly likely that a threshold buffer zone will need to be set.
[0051] As an example, the demand-specific index corresponding to the current time can be determined based on the difference between the buffer demand index corresponding to the current time and the buffer demand index corresponding to each time within the preset window period corresponding to the current time.
[0052] For example, the formula for determining the demand-specific index corresponding to the current moment can be: ; Where X is the demand-specific indicator at the current moment. This is the normalization function. n is the number of times within the preset window period corresponding to the current time; in this embodiment, the time can be the data acquisition time. j is the sequence number of the times within the preset window period corresponding to the current time. It is the buffer demand indicator corresponding to the current moment. It is the demand-specific indicator corresponding to the j-th time within the preset window period corresponding to the current time.
[0053] Alternatively, n can also be the number of randomly selected moments within the historical time period, and j can also be the sequence number of the randomly selected moments within the historical time period. It can also be a demand-specific indicator corresponding to the j-th randomly selected moment within a historical time period. The historical time period can be a past time period, and its end time can be the moment preceding the current moment.
[0054] It should be noted that when A larger value often indicates that the current buffer zone demand index is larger than most historical buffer zone demand indices, suggesting that the current buffer zone demand index is relatively unique and that the fluctuating exhaust gas temperature is more intense. Therefore, switching the bypass valve at this time would cause greater damage to the equipment, and it would also indicate that the control threshold needs to be adjusted to avoid frequent switching.
[0055] Step S4: Based on the pre-acquired core heat exchange surface temperature and exhaust gas flow rate within the preset window period, as well as the demand-specific indicators corresponding to the current moment, adaptively set the threshold buffer interval corresponding to the current moment, and perform operation control based on the temperature lag prediction value and the threshold buffer interval.
[0056] The temperature of the core heat exchange surface of the heat exchanger can characterize the temperature inside the heat exchanger, and it can be collected by a temperature sensor.
[0057] It should be noted that during the heat recovery process of boron expansion and exhaust air, the stability of heat recovery has a significant impact on the buffer zone. When heat recovery is stable, the buffer zone can be appropriately reduced to allow more heat to be recovered by the equipment. When heat recovery is unstable, it indicates that the system is experiencing fluctuations, and in this case, the buffer zone should be appropriately expanded to avoid safety risks.
[0058] As an example, this step may include the following steps: The first step is to determine the average temperature of the core heat exchange surface of all heat exchangers within the preset window period corresponding to each time as the representative temperature of the heat exchange surface at each time if the demand-specific index corresponding to the current time is less than or equal to the preset specific threshold.
[0059] The preset specificity threshold can be a pre-set threshold that can be adaptively set based on the actual scenario. For example, the preset specificity threshold can be set to 0.6.
[0060] Optionally, if the demand-specific index corresponding to the current moment is greater than a preset specific threshold, the bypass valve is opened.
[0061] In practice, when the demand-specific index at the current moment is greater than the preset specific threshold, it often indicates that the equipment's operating condition differs significantly from historical data, and the exhaust gas temperature fluctuates considerably. In this case, the bypass valve can be opened, and heat recovery from the exhaust gas at this moment can be disabled. When the demand-specific index at the current moment is less than or equal to the preset specific threshold, heat recovery from the exhaust gas at this moment is usually possible. In this case, the preset control threshold can be initially corrected to obtain an initial corrected control threshold. The preset control threshold can be a pre-set temperature threshold used to control the opening and closing of the bypass valve, and it can be set manually based on experience.
[0062] The formula for determining the initial correction control threshold can be: ; in, It is the initial correction control threshold. This is a preset control threshold. X is the demand-specific indicator corresponding to the current moment.
[0063] The second step is to determine the characteristic value of the heat exchanger temperature change at each moment within the preset window period corresponding to the current moment, based on the difference between the representative temperature of the heat exchange surface at the next moment and the representative temperature of the heat exchange surface at the previous moment within the preset window period corresponding to the current moment.
[0064] For example, the formula for determining the characteristic value of heat exchanger temperature change at different times within a preset window period corresponding to the current time can be: ; in, It is the characteristic value of the heat exchanger temperature change at the j-th time point within the preset window period corresponding to the current time. j is the sequence number of the time point within the preset window period corresponding to the current time. It is an absolute value function. It is the temperature of the heat exchange surface at the j-th moment within the preset window period corresponding to the current moment. It is the temperature of the heat exchange surface at the (j-1)th moment within the preset window period corresponding to the current moment. It is a pre-set factor greater than 0, mainly used to prevent the denominator from being 0, and it can be 0.0001.
[0065] The third step, based on the heat exchanger temperature change characteristic values for all times within the preset window period corresponding to the current time, and the exhaust gas flow rate within the preset window period, adaptively setting the threshold buffer for the current time may include the following sub-steps: The first sub-step, determining the airflow stability corresponding to the current moment based on the exhaust gas flow rate within the preset window period, may include the following steps: First, by using pressure sensors installed on the inlet and outlet sides of the heat recovery device, the resistance of the exhaust gas entering the heat recovery device at each moment within the preset window period corresponding to the current moment is obtained, thus forming a target resistance sequence.
[0066] The target resistance sequence can be a time series. The heat recovery device is also known as a heat recovery unit.
[0067] Next, based on the variance of the target resistance sequence and the standard deviation of the exhaust gas flow rate within the preset window period corresponding to the current moment, the airflow stability corresponding to the current moment is determined.
[0068] For example, the formula for determining the airflow stability at the current moment can be: ; Where H represents the airflow stability at the current moment. It is an exponential function with the natural constant as its base. It is the variance of all resistances in the target resistance sequence. It is the standard deviation of exhaust gas flow rate at all times within the preset window period corresponding to the current time.
[0069] It should be noted that in practice, a stable airflow can provide a stable heat source for the heat recovery system, which has a strong impact on the stability of the heat recovery system. When H is larger, it usually indicates that the variance of all resistances in the target resistance sequence is smaller, and the standard deviation of the exhaust gas flow rate is smaller; it usually indicates that the resistance of the exhaust gas entering the heat recovery device is more stable, and the change in exhaust gas flow rate is more stable; it usually indicates that the exhaust gas flow distribution is more stable.
[0070] The second sub-step is to determine the heat exchanger temperature stability at the current moment based on the characteristic values of heat exchanger temperature changes at all times within the preset window period corresponding to the current moment.
[0071] For example, the temperature stability of the heat exchanger at the current moment can be determined based on the variance of the characteristic values of the heat exchanger temperature change at all times within the preset window period corresponding to the current moment.
[0072] For example, the formula for determining the temperature stability of the heat exchanger at the current moment can be: ; Where F represents the heat exchanger temperature stability at the current moment. It is an exponential function with the natural constant as its base. U is the variance of the characteristic values of the heat exchanger temperature change at all times within the preset window period corresponding to the current time.
[0073] It should be noted that the larger the value of F, the more stable the temperature distribution of the heat exchanger tends to be.
[0074] The third sub-step is to determine the heat recovery stability coefficient corresponding to the current moment by multiplying the airflow stability and the heat exchanger temperature stability at the current moment.
[0075] It should be noted that the higher the heat recovery stability coefficient at the current moment, the more stable the heat recovery is at that moment.
[0076] The fourth sub-step, setting the threshold buffer corresponding to the current time based on the heat recovery stability coefficient mentioned above, may include the following steps: First, if the heat recovery stability coefficient at the current moment is greater than or equal to the first preset stability threshold, then the stability is considered to be high. At this time, the initial correction control threshold can be reduced to obtain the target control threshold, thereby narrowing the buffer zone.
[0077] The first preset stability threshold can be a pre-set threshold, which can be 0.6.
[0078] For example, by reducing the initial correction control threshold, the formula for obtaining the target control threshold can be: ; in, It is the target control threshold. It is the initial correction control threshold. It is the first preset stable threshold.
[0079] Next, if the heat recovery stability coefficient at the current moment is less than the first preset stability threshold, and the heat recovery stability coefficient at the current moment is greater than or equal to the second preset stability threshold, then the stability is considered to be moderate and the safety risk is low. Therefore, the initial correction control threshold does not need to be corrected. At this time, the target control threshold can be directly set as the initial correction control threshold.
[0080] The second preset stability threshold can be a pre-set threshold that is less than the first preset stability threshold, and it can be 0.4.
[0081] Then, if the heat recovery stability coefficient at the current moment is less than the second preset stability threshold, it is considered that the stability is low at this time. At this time, the initial correction control threshold can be increased to obtain the target control threshold, thereby expanding the buffer space.
[0082] For example, by increasing the initial correction control threshold, the formula corresponding to the target control threshold can be: ; in, It is the target control threshold. It is the initial correction control threshold. It is the second preset stability threshold.
[0083] Continue by constructing the threshold buffer corresponding to the current moment based on the target control threshold and the preset control threshold.
[0084] The larger of the target control threshold and the preset control threshold can be the maximum value between the threshold buffers at the current time, and the smaller of the target control threshold and the preset control threshold can be the minimum value between the threshold buffers at the current time.
[0085] The fourth step is to perform operational control based on the temperature hysteresis prediction and the threshold buffer.
[0086] For example, if the temperature lag prediction value at the current moment is greater than the maximum value between the threshold buffers, the bypass valve is controlled to be open; if the temperature lag prediction value at the current moment is less than or equal to the maximum value between the threshold buffers, the bypass valve is controlled to be closed.
[0087] It should be noted that by setting the threshold buffer zone through the above steps, the problem of frequent bypass valve switching when the exhaust temperature fluctuates slightly around the threshold is solved to some extent. Subsequently, during the operation of the heat recovery system, the operating status of the equipment can be monitored and recorded to ensure its normal operation. Specifically, this includes: real-time tracking of parameters such as bypass valve switching frequency, heat exchanger wall temperature, and heat recovery efficiency to verify whether the buffer zone avoids frequent switching and prevents condensation corrosion, ensuring compliance with design goals; storing buffer zone adjustment records and corresponding operating condition data (such as process batches and ambient temperature); periodically analyzing switching frequency and energy consumption changes to optimize the basic threshold and initial buffer zone settings; if abnormalities such as valve jamming or sudden temperature changes are detected, the buffer zone can be temporarily expanded or forced bypass can be initiated, triggering the early warning system to push handling suggestions; and the original zone settings can be restored after the fault is resolved.
[0088] refer to Figure 2 Based on the same inventive concept as the above-described method embodiments, this invention provides an operation control system for a boron exhaust air heat recovery system. This system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of an operation control method for a boron exhaust air heat recovery system, specifically including: The temperature lag prediction value determination module 201 is used to determine the temperature lag prediction value corresponding to the current moment based on the cross-sectional area and length of the exhaust duct included in the boron expansion exhaust heat recovery system, as well as the exhaust gas flow rate, exhaust duct inlet temperature and exhaust duct outlet temperature of the boron expansion exhaust heat recovery system in the current time period. The current moment is the end moment of the current time period. The buffer zone demand index determination module 202 is used to determine the buffer zone demand index corresponding to the current time based on the temperature lag prediction values of all times within the preset window period corresponding to the current time. Similarly, it determines the buffer zone demand index corresponding to each time. The demand-specific index determination module 203 is used to determine the demand-specific index corresponding to the current time based on the buffer inter-demand index corresponding to all times within the preset window period corresponding to the current time if the inter-buffer demand index corresponding to the current time is greater than or equal to the preset demand threshold. The interval setting and operation control module 204 is used to adaptively set the threshold buffer interval corresponding to the current moment based on the temperature of the core heat exchange surface of the heat exchanger and the exhaust gas flow rate within the preset window period, as well as the demand-specific indicators corresponding to the current moment, and to perform operation control based on the temperature lag prediction value and the threshold buffer interval.
[0089] Figure 3 This is a schematic diagram of the structure of a computer device provided in an embodiment of the present invention. For example, as shown... Figure 3 As shown, the computer device 300 includes: a memory 301, a processor 302, and a computer program 303 stored in the memory 301 and running on the processor 302. When the processor 302 executes the computer program 303, the computer device can execute any of the aforementioned boron exhaust heat recovery system operation control methods.
[0090] Based on the same inventive concept as the above-described method embodiments, the present invention provides a server, including a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, causing the device to execute any of the above-described operation control methods for a boron exhaust heat recovery system.
[0091] Based on the same inventive concept as the above-described method embodiments, the present invention provides a computer program product comprising: computer program code, which, when executed on a computer, causes the computer to execute any of the above-described methods for controlling the operation of a boron exhaust heat recovery system.
[0092] Based on the same inventive concept as the above-described method embodiments, the present invention provides a computer-readable storage medium storing computer program code, which, when executed on a computer, causes the computer to perform any of the above-described boron exhaust heat recovery system operation control methods.
[0093] In summary, this invention can dynamically set the temperature threshold buffer zone to avoid frequent opening and closing of the bypass valve when the exhaust temperature fluctuates slightly around the threshold, reducing wear on valve seals. Combined with temperature hysteresis prediction and heat exchanger wall temperature monitoring, it avoids condensation corrosion caused by low-temperature exhaust gas entering the heat recovery unit, extending the service life of core components such as bypass valves and heat exchangers. Simultaneously, it predicts the actual temperature of the exhaust gas delivered to the heat exchanger based on historical and real-time data, reducing ineffective heat recovery. Furthermore, it dynamically adjusts the buffer zone range based on heat recovery stability, narrowing the zone during periods of high stability to incorporate more recoverable waste heat, thereby improving heat recovery efficiency, reducing system operating energy consumption, and ultimately enhancing the heat recovery effect of the boron-enhanced exhaust air.
[0094] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.
Claims
1. A method for operating and controlling a boron exhaust heat recovery system, characterized in that, Includes the following steps: Based on the pre-obtained cross-sectional area and length of the exhaust duct included in the boron expansion exhaust heat recovery system, as well as the exhaust gas flow rate, exhaust duct inlet temperature and exhaust duct outlet temperature of the boron expansion exhaust heat recovery system in the current time period, the temperature lag prediction value corresponding to the current moment is determined, where the current moment is the end moment of the current time period. Based on the pre-acquired temperature lag prediction values for all times within the preset window period corresponding to the current time, the buffer zone demand index corresponding to the current time is determined. Similarly, the buffer zone demand index corresponding to each time is determined. If the buffer demand index at the current moment is greater than or equal to the preset demand threshold, then the demand-specific index at the current moment is determined based on the buffer demand index at all moments within the preset window period corresponding to the current moment. Based on the pre-acquired core heat exchanger surface temperature and exhaust gas flow rate within a preset window period, as well as the demand-specific indicators corresponding to the current moment, the threshold buffer zone corresponding to the current moment is adaptively set, and the operation control is performed based on the temperature lag prediction value and the threshold buffer zone.
2. The operation control method of a boron exhaust air heat recovery system according to claim 1, characterized in that, The step of determining the temperature lag prediction value corresponding to the current moment based on the pre-acquired cross-sectional area and length of the exhaust duct of the boron expansion and exhaust heat recovery system, as well as the exhaust gas flow rate, exhaust duct inlet temperature, and exhaust duct outlet temperature of the boron expansion and exhaust heat recovery system in the current time period, includes: Based on the average value of all waste gas flow rates within the current time period, as well as the cross-sectional area and length of the exhaust duct, determine the transmission delay representative time index corresponding to the current moment; Based on the average inlet temperature of all exhaust ducts during the current time period and the average outlet temperature of all exhaust ducts during the current time period, determine the temperature difference representative index corresponding to the current moment. The ratio between the temperature difference representative index corresponding to the current moment and the transmission delay representative time index is determined as the exhaust gas temperature loss coefficient corresponding to the current moment. Based on the variance of all exhaust gas flow rates within the current time period, and the absolute value of the difference between the mean of all exhaust gas flow rates within the current time period and the exhaust gas flow rate at the current moment, the target confidence factor corresponding to the current moment is determined. Based on the exhaust gas temperature loss coefficient and target confidence factor at the current moment, and the exhaust duct inlet temperature at the current moment, determine the temperature lag prediction value at the current moment.
3. The operation control method of a boron exhaust air heat recovery system according to claim 2, characterized in that, The step of determining the transmission delay representative time index corresponding to the current moment based on the average of all exhaust gas flow rates within the current time period, and the cross-sectional area and length of the exhaust duct, includes: The ratio between the average value of all waste gas flow rates within the current time period and the cross-sectional area of the exhaust duct is determined as the representative flow velocity index corresponding to the current moment. The ratio between the length of the exhaust duct and the flow velocity representative index corresponding to the current moment is determined as the transmission delay representative time index corresponding to the current moment.
4. The operation control method of a boron exhaust heat recovery system according to claim 1, characterized in that, The step of determining the buffer zone demand index corresponding to the current moment based on the pre-acquired temperature lag prediction values for all moments within a preset window period corresponding to the current moment includes: The intensity of temperature fluctuation at the current moment is determined based on the variance and frequency of change of the temperature lag prediction values at all times within the preset window period corresponding to the current moment. Based on the difference between the preset control threshold and the temperature lag prediction value corresponding to the current moment, as well as the temperature fluctuation intensity corresponding to the current moment, the buffer demand index corresponding to the current moment is determined.
5. The operation control method of a boron exhaust heat recovery system according to claim 1, characterized in that, The step of determining the demand-specific indicators corresponding to the current moment based on the inter-buffer demand indicators corresponding to all moments within the preset window period corresponding to the current moment includes: Based on the difference between the inter-buffer demand index corresponding to the current time and the inter-buffer demand index corresponding to each time within the preset window period corresponding to the current time, the demand-specific index corresponding to the current time is determined.
6. The operation control method of a boron exhaust air heat recovery system according to claim 1, characterized in that, The step of adaptively setting the threshold buffer zone corresponding to the current moment based on the pre-acquired core heat exchange surface temperature and exhaust gas flow rate within a preset window period, and the demand-specific indicators corresponding to the current moment, includes: If the demand-specific index corresponding to the current moment is less than or equal to the preset specific threshold, then the average temperature of all heat exchanger core heat exchange surfaces within the preset window period corresponding to each moment is determined as the representative temperature of the heat exchange surface corresponding to each moment. Based on the difference between the representative temperature of the heat exchange surface at the next time step and the representative temperature of the heat exchange surface at the previous time step within the preset window period corresponding to the current time step, determine the characteristic value of the heat exchanger temperature change at each time step within the preset window period corresponding to the current time step. Based on the characteristic values of heat exchanger temperature change at all times within the preset window period corresponding to the current time, and the exhaust gas flow rate within the preset window period, the threshold buffer zone corresponding to the current time is adaptively set.
7. The operation control method for a boron exhaust heat recovery system according to claim 6, characterized in that, The step of adaptively setting the threshold buffer zone corresponding to the current moment based on the characteristic values of heat exchanger temperature changes at all times within the preset window period corresponding to the current moment, and the exhaust gas flow rate within the preset window period, includes: The airflow stability at the current moment is determined based on the exhaust gas flow rate within the preset window period corresponding to the current moment. The heat exchanger temperature stability at the current moment is determined based on the characteristic values of heat exchanger temperature change at all times within the preset window period corresponding to the current moment. The product of the airflow stability and the heat exchanger temperature stability at the current moment is determined as the heat recovery stability coefficient at the current moment. Based on the heat recovery stability coefficient at the current moment, set the threshold buffer for the current moment.
8. The operation control method of a boron exhaust air heat recovery system according to claim 7, characterized in that, The step of determining the airflow stability at the current moment based on the exhaust gas flow rate within a preset window period includes: The resistance of the exhaust gas entering the heat recovery device within the preset window period corresponding to the current time is obtained to form a target resistance sequence; The airflow stability at the current moment is determined based on the variance of the target resistance sequence and the standard deviation of the exhaust gas flow rate within the preset window period corresponding to the current moment.
9. The operation control method of a boron exhaust air heat recovery system according to claim 7, characterized in that, The step of determining the heat exchanger temperature stability at the current moment based on the characteristic values of heat exchanger temperature changes at all times within the preset window period corresponding to the current moment includes: The temperature stability of the heat exchanger at the current moment is determined based on the variance of the characteristic values of the heat exchanger temperature change at all times within the preset window period corresponding to the current moment.
10. The operation control method of a boron exhaust air heat recovery system according to claim 6, characterized in that, The method further includes: If the demand-specific index corresponding to the current moment is greater than the preset specific threshold, then the bypass valve is opened.