A method and system for regulating a molecular sieve adsorption purification

Abstract

The present application belongs to the technical field of molecular sieve performance detection, and relates to a kind of molecular sieve adsorption purification regulation method and system, detection method includes: S1, constructs molecular sieve adsorption capacity curve;S2, calculate the residual adsorption time of molecular sieve;S3, molecular sieve adsorption purification regulation: compare the residual adsorption time of molecular sieve with the regeneration time required for molecular sieve in regeneration stage, and regulate molecular sieve adsorption purification process.The method provided by the present application can determine whether the adsorption of molecular sieve reaches saturation in real time, and adjust the purification process according to the adsorption result, realize the accurate regulation of molecular sieve adsorption purification process, and ensure the stable operation of molecular sieve purification process.

Description

Technical Field

[0001] This invention belongs to the field of molecular sieve performance testing technology, and relates to a method and system for regulating molecular sieve adsorption and purification, which is used in the regulation of adsorption and purification in large-scale air separation devices. Background Technology

[0002] Large-scale air separation units typically employ deep freezing to separate air. However, the freezing and precipitation of water, carbon dioxide, and other impurities in the air at low temperatures can clog gas channels and tray sieves. Simultaneously, excessive accumulation of acetylene and hydrocarbons in the distillation column can lead to explosions. To improve the safety, reliability, and economy of large-scale air separation units, air purification is essential to remove impurities such as water, carbon dioxide, acetylene, and hydrocarbons. This purification primarily occurs using molecular sieves. Molecular sieves possess high adsorption capacity, strong selectivity, and high-temperature resistance, achieving air purification by adsorbing impurities. However, the adsorption capacity of molecular sieves is limited. When the adsorption of a certain molecule reaches saturation, there is no further adsorption capacity. Continued adsorption will cause molecular sieve permeation, affecting the safe and stable operation of the air separation unit. In existing technologies, when the molecular sieve's adsorption capacity approaches saturation, it must be regenerated to restore its adsorption capacity before resuming adsorption. Therefore, to ensure the performance and purification effect of the molecular sieve, real-time monitoring of its actual adsorption capacity is necessary to determine whether to continue adsorption or regenerate.

[0003] Furthermore, in practical applications, large-scale air separation units typically employ a molecular sieve purification process with two molecular sieves used alternately to ensure continuous air supply. One molecular sieve operates in the adsorption phase, while the other operates in the regeneration phase. Therefore, the ideal purification process is one where the adsorption and regeneration phases are completed simultaneously, or where the regeneration phase completes first, followed by the adsorption phase. This not only ensures continuous purification but also reduces time consumption and improves purification efficiency.

[0004] Therefore, in actual purification processes, it is necessary to test the adsorption performance of molecular sieves to determine the adsorption time during the adsorption phase. This adsorption time is then compared with the regeneration time during the regeneration phase to ensure that the adsorption time is greater than or equal to the regeneration time. Current technologies typically determine the adsorption time based on the theoretical saturation adsorption capacity of the molecular sieve. However, factors such as airflow, molecular sieve packing density, and external environmental conditions can cause discrepancies between the actual adsorption capacity and the theoretical saturation adsorption capacity. Furthermore, if the calculation is still based on the theoretical saturation adsorption capacity, fluctuations in the actual adsorption time will occur, making it difficult to control the regeneration time. This often results in significant differences between the actual adsorption and regeneration phases, or adsorption reaching saturation but regeneration not yet complete. Consequently, the purification process becomes unstable and difficult to regulate. Summary of the Invention

[0005] To address the technical problem of unstable operation in existing molecular sieve purification processes, this invention provides a method and system for regulating molecular sieve adsorption and purification.

[0006] This invention constructs an actual curve equation by collecting the carbon dioxide adsorption capacity of molecular sieves at different inlet temperatures; further, it calculates the remaining adsorption time of the molecular sieve based on the real-time carbon dioxide adsorption capacity and compares it with the time to complete regeneration. This allows for real-time determination of whether the adsorption of the molecular sieve has reached saturation, and the purification process can be adjusted according to the adsorption results. This achieves precise control of the molecular sieve adsorption purification process and ensures stable operation of the molecular sieve purification process.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] This invention provides a method for regulating molecular sieve adsorption and purification, comprising the following steps:

[0009] S1. Constructing molecular sieve adsorption capacity curves

[0010] S1.1 Set the working temperature of the molecular sieve, introduce air into the molecular sieve until the carbon dioxide concentration after adsorption by the molecular sieve is 1 ppm, and record the total adsorption time; and obtain the maximum adsorption capacity of the molecular sieve for adsorbing carbon dioxide at each working temperature according to the following formula.

[0011] Q max =C×D×T

[0012] Among them: Q max Maximum adsorption capacity, in Nm³ 3 C represents airflow rate, in Nm³. 3 / h; D is the carbon dioxide content in the introduced air; T is the total adsorption time, in hours.

[0013] S1.2. Using the operating temperature as the x-axis and 90%–95% of the maximum adsorption capacity as the y-axis, a molecular sieve adsorption capacity curve is constructed through regression analysis.

[0014] S2. Calculate the remaining adsorption time of the molecular sieve.

[0015] S2.1 In the molecular sieve adsorption purification process, air is introduced into the molecular sieve, and the inlet temperature T of the molecular sieve is collected at each time point according to the set adsorption time interval ΔT. 实际 Airflow rate and carbon dioxide content in the air;

[0016] S2.2, Set the inlet temperature value T 实际Substituting the values ​​into the molecular sieve adsorption capacity curve from step S1, the real-time maximum adsorption capacity Q of the molecular sieve at each time point is calculated. 实时 ;

[0017] S2.3 Calculate the actual adsorption capacity Q of the molecular sieve for carbon dioxide. 实际 ;

[0018] Q 实际 =C×D×ΔT

[0019] C represents airflow rate, measured in Nm³. 3 / h; D is the carbon dioxide content in the air;

[0020] S2.4 Calculate the remaining adsorption time of the molecular sieve according to the following formula:

[0021] T 剩余 =(Q 实时 -Q 累积 ) / A 瞬时

[0022] in:

[0023] T 剩余 Q represents the remaining adsorption time of the molecular sieve, in minutes. 累积 Q represents the actual amount of carbon dioxide adsorbed by the molecular sieve at all time points. 实际 The sum, in Nm 3 A 瞬时 The actual amount of carbon dioxide adsorbed by the molecular sieve in the previous 1 minute at the current time point is Q. 实际 The ratio of the sum to time, in Nm 3 / min;

[0024] S3, Regulation of Molecular Sieve Adsorption and Purification

[0025] The remaining adsorption time T of the molecular sieve 剩余 The regeneration time T required for the molecular sieve in the regeneration stage 再生 Comparisons are made, and the adsorption and purification functions of the molecular sieve are adjusted based on the comparison results.

[0026] If T 再生 <T 剩余 This indicates that the time required for the molecular sieve to reach adsorption saturation is greater than the regeneration time required for the molecular sieve in the regeneration stage, indicating stable operation and continued adsorption and purification by the molecular sieve.

[0027] If T 再生 ≥T 剩余 This indicates that the time required for the molecular sieve to reach adsorption saturation is less than or equal to the regeneration time required for the molecular sieve in the regeneration stage. If the operation is unstable, the adsorption and purification work of the molecular sieve needs to be adjusted.

[0028] Furthermore, the operating temperature range is defined as 7°C to 18°C.

[0029] Further specifying, the regeneration time T required for the molecular sieve in the regeneration stage 再生 This includes pressure relief time, pressure equalization time, heating time, and cold blowing time.

[0030] Further specifying, if T 再生 ≥T 剩余 In this case, the adsorption and purification process can be controlled by extending the remaining adsorption time of the molecular sieve or shortening the regeneration time required for the molecular sieve in the regeneration stage.

[0031] Furthermore, the extension of the remaining adsorption time of the molecular sieve is achieved by reducing the inlet air flow rate, reducing the carbon dioxide content in the air, or lowering the inlet temperature of the molecular sieve.

[0032] Furthermore, the regeneration time required for the molecular sieve to shorten the regeneration stage can be achieved by increasing the heating temperature of the molecular sieve, increasing the amount of gas used for cold blowing of the molecular sieve, or by manual switching.

[0033] A detection system for implementing the aforementioned molecular sieve adsorption and purification control method includes:

[0034] Data acquisition module: used to collect data on the molecular sieve's operating temperature, inlet temperature, air flow rate, carbon dioxide content in the air, total adsorption time, and adsorption time interval;

[0035] The data analysis module is used to calculate the maximum adsorption capacity and 90%–95% of the maximum adsorption capacity based on airflow, carbon dioxide content in the air, and total adsorption time; to construct the molecular sieve adsorption capacity curve based on the molecular sieve's operating temperature and 90%–95% of the maximum adsorption capacity; and to calculate the actual amount of carbon dioxide adsorbed by the molecular sieve, Q, based on airflow, carbon dioxide content in the air, and adsorption time interval. 实际 Used to calculate the real-time adsorption capacity Q of a molecular sieve based on the inlet temperature and the molecular sieve adsorption capacity curve. 实时 Used to calculate the remaining adsorption time T of the molecular sieve according to the formula. 剩余 ;

[0036] Comparison module: used to compare T 剩余 The regeneration time T required for the molecular sieve in the regeneration stage 再生 The comparison is performed, and the comparison result is fed back to the control module.

[0037] It also includes a control module, which is used to regulate the adsorption and purification process of the molecular sieve based on the comparison results fed back by the comparison module.

[0038] Further specifying, the data acquisition module includes a temperature sensor and a flow meter; the temperature sensor is located at the inlet of the molecular sieve, and the flow meter is located at the outlet of the molecular sieve.

[0039] Furthermore, the data acquisition module also includes a carbon dioxide content detection and analysis instrument A installed at the molecular sieve air inlet and a carbon dioxide content detection and analysis instrument B installed at the molecular sieve air outlet.

[0040] Compared with the prior art, the beneficial effects of the present invention are:

[0041] 1. This invention collects relevant operating parameters to calculate the maximum adsorption capacity of the molecular sieve at different operating temperatures, constructs the molecular sieve adsorption capacity curve through regression analysis, and then calculates the actual cumulative value of carbon dioxide adsorbed by the molecular sieve in the molecular sieve purification process by collecting parameters such as inlet temperature in real time, calculates the remaining adsorption time of the molecular sieve in real time, and compares it with the regeneration time required by the molecular sieve in the regeneration stage. This ensures that the molecular sieve in the adsorption stage reaches saturation adsorption after the regeneration of another molecular sieve is completed, thereby achieving precise control of the molecular sieve adsorption purification process.

[0042] 2. This invention effectively avoids molecular sieve penetration through real-time monitoring, which not only achieves the goal of safe and stable system operation, but also monitors the service life of the molecular sieve.

[0043] 3. By constructing a molecular sieve adsorption capacity curve, this invention can accurately determine the rate of decline in molecular sieve adsorption performance through periodic calculations. It can also determine whether the adsorption capacity of the molecular sieve can meet the process operation requirements, ultimately achieving the purpose of planned replenishment or replacement of molecular sieves and ensuring the normal operation of the molecular sieve adsorption and purification process. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the molecular sieve adsorption and purification control method of the present invention;

[0045] Figure 2 To construct the molecular sieve adsorption capacity curve for regression analysis. Detailed Implementation

[0046] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to specific examples and accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0047] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0048] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0049] See Figure 1 This invention provides a method for regulating molecular sieve adsorption and purification, comprising the following steps:

[0050] S1. Constructing molecular sieve adsorption capacity curves

[0051] S1.1 Set the working temperature of the molecular sieve, introduce air into the molecular sieve until the carbon dioxide concentration after adsorption by the molecular sieve is 1 ppm, record the total adsorption time and obtain the maximum adsorption capacity of the molecular sieve for adsorbing carbon dioxide.

[0052] S1.2. Using the operating temperature as the x-axis and 90%–95% of the maximum adsorption capacity as the y-axis, a molecular sieve adsorption capacity curve is constructed through regression analysis.

[0053] In this step, the working temperature of the molecular sieve is set according to its performance. Generally, the working temperature range is 7℃~18℃, which can meet the requirements of large-scale air separation units for the working temperature of the molecular sieve.

[0054] The maximum adsorption capacity is the adsorption capacity corresponding to a carbon dioxide concentration of 1 ppm after adsorption by the molecular sieve. The maximum adsorption capacity is calculated according to the following formula.

[0055] Q max =C×D×T

[0056] Q max Maximum adsorption capacity, in Nm³ 3 ;

[0057] C represents airflow rate, measured in Nm³. 3 / h;

[0058] D represents the amount of carbon dioxide introduced into the air;

[0059] T represents the total adsorption time, in hours (h).

[0060] Preferably, the total adsorption time is the time taken for the molecular sieve to go from the start of adsorption to the point where the carbon dioxide concentration after adsorption equals 1 ppm. The carbon dioxide content in the introduced air is in the ppm range.

[0061] In this embodiment, the molecular sieve adsorption capacity curve is constructed using 90% to 95% of the maximum adsorption capacity. This is because, in actual operation, the fluctuations in adsorption capacity caused by environmental factors are considered. This ensures accurate control while minimizing the risk of molecular sieve oversaturation and breakdown during actual operation. Preferably, the molecular sieve adsorption capacity curve is constructed using 90% of the maximum adsorption capacity.

[0062] S2. Calculate the remaining adsorption time of the molecular sieve.

[0063] S2.1 In the molecular sieve adsorption purification process, air is introduced into the molecular sieve, and the inlet temperature T of the molecular sieve is collected at each time point according to the set adsorption time interval ΔT. 实际 Airflow rate and carbon dioxide content in the air;

[0064] S2.2, Set the inlet temperature value T 实际 Substituting the values ​​into the molecular sieve adsorption capacity curve from step S1, the real-time maximum adsorption capacity Q of the molecular sieve at each time point is calculated. 实时 ;

[0065] S2.3 Calculate the actual adsorption capacity Q of the molecular sieve for carbon dioxide. 实际 ;

[0066] Q 实际 =C×D×ΔT

[0067] C represents airflow rate, measured in Nm³. 3 / h; D is the carbon dioxide content in the air;

[0068] S2.4 Calculate the remaining adsorption time of the molecular sieve according to the following formula:

[0069] T 剩余 =(Q 实时 -Q 累积 ) / A 瞬时

[0070] in:

[0071] T 剩余 The remaining adsorption time of the molecular sieve, in minutes;

[0072] Q 累积 Q represents the actual amount of carbon dioxide adsorbed by the molecular sieve at all time points. 实际 The sum, in Nm 3;

[0073] A 瞬时 Q represents the actual amount of carbon dioxide adsorbed by the molecular sieve in the previous minute at the current time point. 实际 The ratio of the sum to time, in Nm 3 / min;

[0074] S3, Regulation of Molecular Sieve Adsorption and Purification

[0075] The remaining adsorption time T of the molecular sieve 剩余 The regeneration time T required for the molecular sieve in the regeneration stage 再生 Comparisons are made, and the adsorption and purification functions of the molecular sieve are adjusted based on the comparison results.

[0076] If T 再生 <T 剩余 This indicates that the time required for the molecular sieve to reach adsorption saturation is greater than the regeneration time required for the molecular sieve in the regeneration stage, indicating stable operation and continued adsorption and purification by the molecular sieve.

[0077] If T 再生 ≥T 剩余 This indicates that the time required for the molecular sieve to reach adsorption saturation is less than or equal to the regeneration time required for the molecular sieve in the regeneration stage. If the operation is unstable, the adsorption and purification work of the molecular sieve needs to be adjusted.

[0078] The regeneration time T required for the molecular sieve in the regeneration stage 再生 This includes the pressure relief time, pressure equalization time, heating time, and molecular sieve cold blowing time.

[0079] In this invention, if T 再生 ≥T 剩余 In this case, the adsorption and purification process can be controlled by extending the remaining adsorption time of the molecular sieve or shortening the regeneration time required for the molecular sieve in the regeneration stage.

[0080] In this invention, the remaining adsorption time of the molecular sieve is extended by reducing the inlet flow rate, decreasing the carbon dioxide content in the air, or lowering the inlet temperature of the molecular sieve.

[0081] In this invention, the regeneration time required for the molecular sieve in the regeneration stage is shortened by increasing the heating temperature of the molecular sieve, increasing the amount of gas used for cold blowing of the molecular sieve, or manually switching the process if conditions permit.

[0082] Example 1

[0083] Taking two molecular sieves installed in a large air separation device as an example, the detection method is explained in detail.

[0084] To ensure continuous air supply, large-scale air separation devices typically employ a molecular sieve purification process with two molecular sieves used alternately. One molecular sieve is in the adsorption stage, while the other is in the regeneration stage (the process of driving away the adsorbed substances and restoring the adsorption capacity is called "regeneration").

[0085] The regeneration stage of molecular sieves includes "pressure relief, pressure equalization, heating and cold blowing" operations.

[0086] During implementation, the two molecular sieves were designated as molecular sieve MS1 and molecular sieve MS2, respectively.

[0087] A carbon dioxide content detection and analysis instrument A is installed at the air inlet of each of the two molecular sieves to detect the carbon dioxide content at the air inlet, that is, the carbon dioxide content before the molecular sieve purification.

[0088] A carbon dioxide content detector B is installed at the outlet of both molecular sieves to detect the carbon dioxide content after passing through the molecular sieves, i.e., the carbon dioxide content after purification by the molecular sieves.

[0089] An inlet temperature measuring point T1 is set at the inlet of molecular sieve MS1 to detect the inlet temperature of molecular sieve MS1.

[0090] An inlet temperature measuring point T2 is set at the inlet of molecular sieve MS2 to detect the inlet temperature of molecular sieve MS2.

[0091] Molecular sieve MS1 is currently in the adsorption stage, and molecular sieve MS2 is in the regeneration stage. When molecular sieve MS1 begins adsorption, its inlet temperature is kept constant, while molecular sieve MS2 is in the regeneration stage. After regeneration of molecular sieve MS2 is completed, its current stage is paused in the pressurization stage. When the carbon dioxide content in the analyzer B after molecular sieve MS1 rises to 0.8 ppm (reaching 80% of the control target of 1 ppm), the molecular sieves are switched, i.e., molecular sieve MS1 enters the regeneration stage, and molecular sieve MS2 enters the adsorption stage.

[0092] Specifically, the regulation process of molecular sieve adsorption and purification is as follows:

[0093] S1. Constructing molecular sieve adsorption capacity curves

[0094] S1.1 Set the working temperature of the molecular sieve, introduce air into the molecular sieve until the carbon dioxide concentration after adsorption by the molecular sieve is 1 ppm, and record the total adsorption time; and obtain the maximum adsorption capacity of the molecular sieve for adsorbing carbon dioxide at each working temperature according to the following formula.

[0095] In this embodiment, the molecular sieve adsorption capacity curve was constructed under ideal conditions, such as constant operating temperature, flow rate, and carbon dioxide content.

[0096] Preferably, the operating temperature is set in increments of 1℃ within the range of 7℃ to 18℃. Air is introduced, and the molecular sieve adsorbs carbon dioxide from the air. When the concentration of carbon dioxide after adsorption by the molecular sieve is detected to be equal to 1 ppm, the total adsorption time is recorded and substituted into Q. max The maximum adsorption capacity of the molecular sieve for carbon dioxide was calculated using the formula C×D×T, and the results are shown in Table 1. Simultaneously, 90% of the maximum adsorption capacity was calculated, and the results are also shown in Table 1.

[0097] Table 1. Results of the maximum adsorption capacity of molecular sieves for carbon dioxide at different operating temperatures.

[0098] 7 875.82 788.238 8 871.86 784.674 9 863.28 776.952 10 853.38 768.042 11 838.86 754.974 12 819.72 737.748 13 797.94 718.146 14 775.5 697.95 15 750.42 675.378 16 722.04 649.836 17 692.34 623.106 18 660.096 594.086

[0099] S1.2. Using the operating temperature as the x-axis and 90% of the maximum adsorption capacity as the y-axis, a molecular sieve adsorption capacity curve was constructed through regression analysis.

[0100] In this embodiment, the molecular sieve adsorption capacity curve is constructed at 90% of the maximum adsorption capacity. This is because, in actual work, the fluctuations in adsorption capacity caused by environmental and other factors are taken into account. While ensuring accurate control, this can minimize the risk of molecular sieve breakdown due to adsorption oversaturation in actual work.

[0101] See Figure 2 The operating temperature and 90% of the maximum adsorption capacity from Table 1 were plotted on a coordinate system. Regression analysis was then performed to construct the molecular sieve adsorption capacity curve, and the equation is as follows:

[0102] Q = -1.245T 2 +13.171T+758.81

[0103] In the equation, Q is the adsorption capacity of the molecular sieve, and T is the operating temperature of the molecular sieve.

[0104] The constructed molecular sieve adsorption capacity curves, with a correlation coefficient R 2 The correlation coefficient is 0.9996, indicating a high correlation and more accurate results.

[0105] S2. Calculate the remaining adsorption time of the molecular sieve.

[0106] In actual operation, when the inlet and outlet valves of molecular sieve MS1 are opened simultaneously, molecular sieve MS1 is in the actual adsorption state.

[0107] Airflow controlled at 300,000 Nm 3The CO2 content is detected approximately per hour using a carbon dioxide content detector A installed at the air inlet of the molecular sieve. During the adsorption and purification process using molecular sieve MS1, the inlet temperature T of the molecular sieve is collected at each time point according to the adsorption time interval ΔT. 实际 1. Measure the airflow rate and the carbon dioxide content in the air; calculate the actual adsorption capacity Q of the molecular sieve for carbon dioxide. 实际 Unit Nm 3 .

[0108] Actual adsorption capacity Q 实际 The air flow rate C (Nm³) entering the molecular sieve at the current adsorption time point is... 3 The adsorption time interval ΔT (s) was calculated from the carbon dioxide concentration in the air (D (ppm)) and the adsorption time interval ( / h).

[0109] Q 实际 =C×D×ΔT

[0110] Inlet temperature value T 实际 Substituting the values ​​into the molecular sieve adsorption capacity curve from step S1, the real-time maximum adsorption capacity Q of the molecular sieve at each time point is calculated. 实时 The remaining adsorption time of molecular sieve MS1 is calculated according to the following formula:

[0111] T 剩余 =(Q 实时 -Q 累积 ) / A 瞬时

[0112] in:

[0113] T 剩余 The remaining adsorption time of the molecular sieve, in minutes;

[0114] Q 累积 Q represents the actual amount of carbon dioxide adsorbed by the molecular sieve at all time points. 实际 The sum, in Nm 3 ;

[0115] A 瞬时 Q represents the actual amount of carbon dioxide adsorbed by the molecular sieve in the previous minute at the current time point. 实际 The ratio of the sum to time, in Nm 3 / min.

[0116] During implementation, the adsorption time interval ΔT is 1s to 2s, preferably 1s; that is, the inlet temperature T is collected at molecular sieve adsorption times of 1s, 2s, 3s, etc. 实际 And the actual amount of carbon dioxide adsorbed by the molecular sieve at each moment, Q. 实际 .

[0117] For example, when the molecular sieve adsorption time is 10 seconds, the inlet temperature T is... 实际 The temperature was set at 14.5℃. Substituting this temperature into the molecular sieve adsorption capacity curve, the real-time maximum adsorption capacity Q was calculated. 实时 =673.51Nm 3 Meanwhile, the carbon dioxide content detector A installed at the air intake detected a carbon dioxide content of 600 ppm and an air flow rate of 300,000 Nm³. 3 / h, calculate the actual adsorption capacity Q 实际 =600×10 -6 ×300000×1 / 3600=0.05Nm 3 .

[0118] Furthermore, after 100 seconds of adsorption, the remaining adsorption time of molecular sieve MS1 is calculated, and the actual adsorption amount Q corresponding to each adsorption time interval within the range of 0 to 100 seconds is determined. 实际 By summing, we get Q. 累积 Then, using 100s as the baseline, the actual adsorption amount Q corresponding to each adsorption time interval within the first minute (i.e., 41s to 100s) is calculated. 实际 Divide the sum by 1min to get A. 瞬时 Finally, the inlet temperature value T at the 100th second will be... 实际 The real-time maximum adsorption capacity Q is obtained by substituting the molecular sieve adsorption capacity curve. 实时 Finally, Q 实时 Q 累积 and A 瞬时 Substituting into the calculation, we get T 剩余 .

[0119] S3, Regulation of Molecular Sieve Adsorption and Purification

[0120] The remaining adsorption time T of molecular sieve MS1 剩余 The time T for regeneration of molecular sieve MS2 再生 Compare them.

[0121] Time T for molecular sieve MS2 to complete regeneration 再生 Including a depressurization time of 6 minutes, a pressure equalization time of 18 minutes, a heating time of 84 minutes, and a cold blowing time of 132 minutes, therefore, T 再生 =240min. The T value was calculated after 100s of adsorption. 剩余 With T 再生 (240 min) Comparison, if T 再生 <T 剩余 If T indicates that molecular sieve MS2 has completed regeneration first, then the purification process is operating stably; no further action is required at this point. 再生 ≥T 剩余This indicates that molecular sieve MS1 has completed adsorption first, and we need to wait for molecular sieve MS2 to complete regeneration; this means that the purification process is unstable. In this case, we can extend the remaining adsorption time of the molecular sieve by reducing the inlet flow rate.

[0122] In the above implementation process, the operation steps of "pressure relief, pressure equalization, heating and cold blowing" in molecular sieve regeneration are all existing technologies, and will not be elaborated on here.

[0123] Example 2

[0124] To implement the molecular sieve adsorption and purification control method of Example 1, this example provides a detection system, including:

[0125] Data acquisition module: used to collect data on the molecular sieve's operating temperature, inlet temperature, air flow rate, carbon dioxide content in the air, total adsorption time, and adsorption time interval;

[0126] The data analysis module is used to calculate the maximum adsorption capacity and 90% of the maximum adsorption capacity based on airflow, carbon dioxide content in the air, and total adsorption time; to construct the molecular sieve adsorption capacity curve based on the molecular sieve's operating temperature and 90% of the maximum adsorption capacity; and to calculate the actual amount of carbon dioxide adsorbed by the molecular sieve, Q, based on airflow, carbon dioxide content in the air, and adsorption time interval. 实际 Used to calculate the real-time adsorption capacity Q of a molecular sieve based on the inlet temperature and the molecular sieve adsorption capacity curve. 实时 Used to calculate the remaining adsorption time T of the molecular sieve according to the formula. 剩余 ;

[0127] Comparison module: used to compare T 剩余 The regeneration time T required for the molecular sieve in the regeneration stage 再生 The comparison is performed, and the comparison result is fed back to the control module.

[0128] as well as

[0129] The control module is used to regulate the adsorption and purification operation of the molecular sieve based on the comparison results fed back by the comparison module.

[0130] In this embodiment, the data acquisition module includes a temperature sensor and a flow meter; the temperature sensor is located at the inlet of the molecular sieve, and the flow meter is located at the outlet of the molecular sieve. The temperature sensor detects the inlet temperature or operating temperature of the molecular sieve. The flow meter monitors the airflow rate entering the molecular sieve.

[0131] In this embodiment, the data acquisition module further includes a carbon dioxide content detection and analysis instrument A installed at the molecular sieve intake and a carbon dioxide content detection and analysis instrument B installed at the molecular sieve outlet. Preferably, the carbon dioxide content detection and analysis instrument A is installed at the intake before the molecular sieve to detect the carbon dioxide content in the air at the intake. The carbon dioxide content detection and analysis instrument B is installed after the molecular sieve to detect the carbon dioxide content after passing through the molecular sieve, thus preventing the molecular sieve from being broken down.

[0132] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for regulating molecular sieve adsorption and purification, characterized in that, Includes the following steps: S1. Constructing molecular sieve adsorption capacity curves S1.1 Set the working temperature of the molecular sieve, introduce air into the molecular sieve until the carbon dioxide concentration after adsorption by the molecular sieve is 1 ppm, and record the total adsorption time; and obtain the maximum adsorption capacity of the molecular sieve for adsorbing carbon dioxide at each working temperature according to the following formula. Q max =C×D×T Among them: Q max Maximum adsorption capacity, in Nm³ 3 C represents airflow rate, in Nm³. 3 / h; D is the carbon dioxide content in the introduced air; T is the total adsorption time, in hours; S1.

2. Using the operating temperature as the x-axis and 90%–95% of the maximum adsorption capacity as the y-axis, a molecular sieve adsorption capacity curve is constructed through regression analysis. S2. Calculate the remaining adsorption time of the molecular sieve. S2.1 In the molecular sieve adsorption purification process, air is introduced into the molecular sieve, and the inlet temperature T of the molecular sieve is collected at each time point according to the set adsorption time interval ΔT. 实际 Airflow rate and carbon dioxide content in the air; S2.2, Set the inlet temperature value T 实际 Substituting the values ​​into the molecular sieve adsorption capacity curve from step S1, the real-time maximum adsorption capacity Q of the molecular sieve at each time point is calculated. 实时 ; S2.3 Calculate the actual adsorption capacity Q of the molecular sieve for carbon dioxide. 实际 ; Q 实际 =C×D×ΔT Where: C is the air flow rate, in Nm³. 3 / h; D is the carbon dioxide content in the air; S2.4 Calculate the remaining adsorption time of the molecular sieve according to the following formula: T 剩余 =(Q 实时 -Q 累积 ) / A 瞬时 Wherein: T 剩余 Q represents the remaining adsorption time of the molecular sieve, in minutes. 累积 Q represents the actual amount of carbon dioxide adsorbed by the molecular sieve at all time points. 实际 The sum, in Nm 3 A 瞬时 The actual amount of carbon dioxide adsorbed by the molecular sieve in the previous 1 minute at the current time point is Q. 实际 The ratio of the sum to time, in Nm 3 / min; S3, Regulation of Molecular Sieve Adsorption and Purification The remaining adsorption time T of the molecular sieve 剩余 The regeneration time T required for the molecular sieve in the regeneration stage 再生 Comparisons are made, and the adsorption and purification functions of the molecular sieve are adjusted based on the comparison results. If T 再生 <T 剩余 This indicates that the time required for the molecular sieve to reach adsorption saturation is greater than the regeneration time required for the molecular sieve in the regeneration stage, indicating stable operation and continued adsorption and purification by the molecular sieve. If T 再生 ≥T 剩余 This indicates that the time required for the molecular sieve to reach adsorption saturation is less than or equal to the regeneration time required for the molecular sieve in the regeneration stage. If the operation is unstable, the adsorption and purification work of the molecular sieve needs to be adjusted.

2. The method for regulating molecular sieve adsorption and purification according to claim 1, characterized in that, In step S1, the operating temperature range is 7℃~18℃.

3. The method for regulating molecular sieve adsorption and purification according to claim 1, characterized in that, In step S3, the regeneration time T required for the molecular sieve in the regeneration stage is... 再生 This includes pressure relief time, pressure equalization time, heating time, and cold blowing time.

4. The method for regulating molecular sieve adsorption and purification according to claim 1, characterized in that, If T 再生 ≥T 剩余 In this case, the adsorption and purification process can be controlled by extending the remaining adsorption time of the molecular sieve or shortening the regeneration time required for the molecular sieve in the regeneration stage.

5. The method for regulating molecular sieve adsorption and purification according to claim 4, characterized in that, The remaining adsorption time of the molecular sieve is extended by reducing the inlet air flow rate, decreasing the carbon dioxide content in the air, or lowering the inlet temperature of the molecular sieve.

6. The method for regulating molecular sieve adsorption and purification according to claim 4, characterized in that, The regeneration time required for the molecular sieve to shorten the regeneration stage can be achieved by increasing the heating temperature of the molecular sieve, increasing the amount of air blown into the molecular sieve, or by manual switching.

7. A detection system for implementing the molecular sieve adsorption and purification control method of claim 1, characterized in that, include: Data acquisition module: used to collect data on the molecular sieve's operating temperature, inlet temperature, air flow rate, carbon dioxide content in the air, total adsorption time, and adsorption time interval; Data analysis module: used to calculate the maximum adsorption capacity based on airflow, carbon dioxide content in the air, and total adsorption time, as well as to calculate 90% to 95% of the maximum adsorption capacity; Used to construct molecular sieve adsorption capacity curves based on the working temperature of the molecular sieve and 90% to 95% of its maximum adsorption capacity; This is used to calculate the actual adsorption capacity Q of the molecular sieve for carbon dioxide based on airflow, air carbon dioxide content, and adsorption time interval. 实际 Used to calculate the real-time adsorption capacity Q of a molecular sieve based on the inlet temperature and the molecular sieve adsorption capacity curve. 实时 Used to calculate the remaining adsorption time T of the molecular sieve according to the formula. 剩余 ; Comparison module: used to compare T 剩余 The regeneration time T required for the molecular sieve in the regeneration stage 再生 The comparison is performed, and the comparison result is fed back to the control module. It also includes a control module, which is used to regulate the adsorption and purification process of the molecular sieve based on the comparison results fed back by the comparison module.

8. The detection system according to claim 7, characterized in that, The data acquisition module includes a temperature sensor and a flow meter; the temperature sensor is located at the inlet of the molecular sieve, and the flow meter is located at the outlet of the molecular sieve.

9. The detection system according to claim 7, characterized in that, The data acquisition module also includes a carbon dioxide content detection and analysis instrument A installed at the air inlet of the molecular sieve and a carbon dioxide content detection and analysis instrument B installed at the air outlet of the molecular sieve.

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