A method for monitoring clogging of an inert gas purification adsorption tank online

Abstract

This invention relates to the field of equipment monitoring technology, and in particular to an online monitoring method for blockage in an inert gas purification adsorption tank. The method includes: collecting operating parameters and status signals; determining baseline parameters; determining an early warning signal for accelerated coking; determining a distributor blockage confirmation signal; determining the blockage severity level; confirming the blockage confirmation signal; performing uninterrupted switching and determining the blockage type and treatment plan. This invention achieves early warning and accurate location of blockage through multi-level differential pressure monitoring and coking temperature rise judgment; eliminates periodic load variations through condition-specific calibration and dynamic tracking of periodic differential pressure recovery rate; ensures judgment reliability through dual judgment of severity and rate, and dual confirmation of time sequence continuity and temperature-differential pressure consistency; and identifies the blockage type online and outputs corresponding treatment plans, covering the complete process from detection to treatment of adsorption tank blockage.

Description

Technical Field

[0001] This invention relates to the field of equipment monitoring technology, and in particular to an online monitoring method for blockage in an inert gas purification adsorption tank. Background Technology

[0002] With the increasing demands for high-purity inert gas quality from the high-end metallurgical industry, the stable operation of the inert gas purification adsorption tank in the total extraction air separation unit is becoming increasingly critical. During long-term service, trace amounts of oil mist carried by the feed gas undergo oxidative polymerization on the surface of the adsorbent in the inlet section. Simultaneously, the adsorbent particles experience wear due to thermal cycling and airflow impact, leading to concentrated blockages, primarily composed of coking deposits and powdery hard lumps, in the inlet gas distributor and the top adsorbent layer. This causes increased differential pressure and flow resistance in the adsorption tank, potentially resulting in downstream gas supply interruptions and significant production losses. Existing technologies largely rely on single-channel differential pressure sensors and fixed thresholds for judgment. Under periodic variable load conditions, the differential pressure signal fluctuates synchronously with the flow rate, easily misinterpreting increased flow rate as blockage. Furthermore, these technologies fail to capture early warning signals such as coking temperature rise and lack multi-parameter cross-validation mechanisms, resulting in significant issues of misjudgment and missed detection.

[0003] Chinese Patent Publication No. CN121869038A discloses an online anti-clogging method for PSA pre-adsorption tower beds. The method includes: operating several pre-adsorption towers in parallel, with each pre-adsorption tower using a multi-layer gradient structure for dense-phase packing of adsorbent, consisting of large-particle activated carbon, activated alumina, and small-particle activated carbon sequentially from bottom to top; monitoring the pressure difference of the pre-adsorption tower bed in real time, and disconnecting the faulty pre-adsorption tower when the pressure difference reaches 0.1-0.2 MPa; performing online water washing on the faulty pre-adsorption tower, followed by alternating purging and vacuuming; and reconnecting a qualified regenerated pre-adsorption tower.

[0004] Therefore, the aforementioned existing technologies have the following technical problems: they use a single-channel sensor to monitor bed differential pressure, lack independent verification methods, and the reliability of differential pressure signals is insufficient; they directly determine that an increase in differential pressure is bed blockage, failing to distinguish between normal differential pressure changes caused by flow fluctuations under periodic variable load conditions and actual bed blockage, and are prone to misjudging flow fluctuations as blockage faults; they directly trigger tower switching based on a single differential pressure threshold, lacking a multi-parameter cross-verification mechanism, and there is a possibility of unnecessary water washing and regeneration due to sensor false alarms; they only focus on the switching-out treatment after blockage occurs, failing to utilize precursor signals such as coking temperature rise that precede differential pressure increases, thus missing the intervention window in the early stages of blockage; they only record data when the differential pressure reaches the target, failing to save the entire trend of differential pressure changes, and differential pressure spikes caused by occasional flow fluctuations are difficult to trace afterward due to the lack of complete data. Summary of the Invention

[0005] To address this, the present invention provides an online monitoring method for blockage in an inert gas purification adsorption tank, which overcomes the problems in the prior art where the use of single-channel total differential pressure monitoring and fixed threshold judgment leads to the easy misjudgment of flow fluctuations under periodic variable load conditions as blockage, a high rate of incorrect tower shutdown, and the failure to utilize early warning signals such as coking temperature rise, resulting in delayed early warning.

[0006] To achieve the above objectives, the present invention provides an online monitoring method for blockage in an inert gas purification adsorption tank, comprising: Based on the risk of oil mist impurity deposition on the feed gas inlet side of the inert gas purification adsorption tank in the stainless steel smelting and supporting full extraction air separation unit, and the operating characteristics of the adsorption tank that cause periodic changes in inlet flow rate due to the switching of adsorption, pressure equalization and regeneration according to the adsorption cycle, the operating parameters and status signals of the inert gas purification adsorption tank are collected. Based on the operating parameters and status signals, multi-condition calibration is performed under clean conditions to determine the differential pressure baseline, temperature profile baseline, and differential pressure recovery rate of the adsorption tank under gas supply and gas outage conditions. Based on the temperature profile baseline, and combined with the inlet section temperature profile signal in the operating parameters and status signals, the degree of coking temperature rise in the inlet section is determined, and a coking acceleration warning signal is determined according to the rate of change of the degree of coking temperature rise. In response to the coking acceleration warning signal being triggered, the distributor blockage confirmation signal is determined by combining the differential pressure signal in the operating parameters and status signals, the periodic gas supply status signal, and the differential pressure reference value. In response to the distributor blockage confirmation signal being triggered, the blockage level is determined by combining the operating parameters and the differential pressure signal in the status signal, the periodic gas supply status signal, the differential pressure reference value, and the differential pressure recovery rate of the reference period. Based on the level of blockage and the degree of coking temperature rise, a blockage confirmation signal is determined; In response to the blockage confirmation signal being triggered, the adsorption tank is switched without interruption, and the blockage type and treatment plan are determined based on the sequential relationship between the degree of coking temperature rise and the abnormality of the differential pressure signal.

[0007] Furthermore, the process of collecting operating parameters and status signals includes: The total pressure difference signal between the inlet and outlet is collected based on the differential pressure sensors installed in the inlet and outlet pipelines of the adsorption tank. Differential pressure signals of the distributor are collected based on differential pressure sensors installed upstream and downstream of the inlet gas distributor; Differential pressure sensors located at the bottom of the ceramic ball layer and in the middle of the bed in the inlet section are used to collect differential pressure signals in the inlet section. Based on temperature sensors installed at multiple temperature measuring points along the axial direction of the inlet section, axial temperature profile signals of the inlet section are collected. Instantaneous inlet flow signals are collected based on a flow sensor installed in the inlet pipe; Based on the communication connection with the periodic gas supply control system, periodic gas supply status signals are collected.

[0008] Furthermore, the process of determining the differential pressure reference value, the temperature profile reference line, and the differential pressure recovery rate over the reference period includes: Based on the initial operating state where the adsorbent inside the adsorption tank does not coke or powder deposit under clean conditions, the inlet gas flow rate is adjusted to multiple preset gas supply flow rate points, and the corresponding total pressure difference, distributor pressure difference, and inlet section pressure difference under stable operating conditions are collected respectively. The correspondence between the gas supply flow rate and each pressure difference parameter is established, and the reference values ​​of the total pressure difference, distributor pressure difference, and inlet section pressure difference corresponding to each flow rate point under the gas supply condition are determined. Based on the clean state, the inlet gas supply valve of the adsorption tank is closed, so that the adsorption tank stops receiving gas and maintains a preset stable time. The total pressure difference, distributor pressure difference and inlet section pressure difference are collected under the condition of no airflow to determine the reference values ​​of the total pressure difference, distributor pressure difference and inlet section pressure difference under the shutdown condition. The temperature profile baseline is determined based on the temperature difference between each temperature measuring point in the inlet section and the temperature in the middle section of the bed. The baseline cycle pressure difference recovery rate is determined based on the ratio of the average pressure difference during the regeneration stage to the average pressure difference during the adsorption stage over multiple consecutive adsorption cycles.

[0009] Furthermore, the process of determining the degree of coking temperature rise in the inlet section includes: Based on the real-time temperature values ​​of each temperature measuring point in the inlet section and the reference temperature value in the middle section of the bed, the real-time temperature difference of each measuring point is determined. The real-time temperature difference at each measuring point is compared with the reference difference value at the corresponding position in the temperature profile baseline to determine the temperature rise amplitude at each measuring point. Based on the temperature rise distribution of each measuring point along the axial direction of the adsorption tank, the location of the maximum temperature rise and the corresponding temperature rise amplitude are determined, and the maximum temperature rise amplitude located in the interface area between the inlet ceramic ball layer and the top adsorbent layer or in the top adsorbent layer area is determined as the coking temperature rise degree of the inlet section.

[0010] Furthermore, the process of determining the coking acceleration warning signal includes: The rate of change of the coking temperature rise is determined by tracking the change trend of the coking temperature rise over multiple consecutive adsorption cycles. In response to the coking temperature rise reaching the coking degree alarm threshold, a coking acceleration warning signal is triggered. When the rate of change of the coking temperature rise reaches the coking rate alarm threshold, a coking acceleration warning signal is triggered.

[0011] Furthermore, the process of determining the distributor blockage confirmation signal includes: The current state of the adsorption or regeneration stage is determined based on the process stage status signal output by the adsorption control system. During the adsorption stage, the degree of deviation of the distributor pressure difference during the adsorption stage is determined based on the measured distributor pressure difference and the distributor pressure difference benchmark value at the corresponding flow point under the gas supply condition. During the regeneration phase, the degree of deviation of the distributor pressure difference during the regeneration phase is determined based on the measured distributor pressure difference and the distributor pressure difference benchmark value under the shutdown condition. In response to the distributor pressure difference deviation reaching the distributor pressure difference deviation threshold in the adsorption stage or the distributor pressure difference deviation reaching the distributor pressure difference deviation threshold in the regeneration stage, a distributor blockage confirmation signal is triggered.

[0012] Furthermore, the process of determining the level of congestion includes: The current state of the adsorption or regeneration stage is determined based on the process stage status signal output by the adsorption control system. The degree of deviation of the total pressure difference is determined based on the measured total pressure difference and the benchmark value of the total pressure difference corresponding to the current stage; The degree of deviation of the inlet section pressure difference is determined based on the measured inlet section pressure difference and the reference value of the inlet section pressure difference corresponding to the current stage. The pressure difference recovery rate for the current cycle is determined based on the ratio of the average pressure difference during the regeneration stage to the average pressure difference during the adsorption stage within the current adsorption cycle. Based on the comparison between the current cycle differential pressure recovery rate and the reference cycle differential pressure recovery rate, the degree of deviation of the cycle differential pressure recovery rate is determined; Based on the deviation of the total differential pressure, the deviation of the inlet differential pressure, and the deviation of the periodic differential pressure recovery rate, the overall flow resistance change state of the adsorption tank, the local resistance change state of the inlet section, and the resistance recovery capability during the regeneration stage are determined respectively, and the blockage level is determined according to the corresponding judgment results of the three.

[0013] Furthermore, the process of determining the blockage confirmation signal includes: Based on the result that the blockage level is consistently at or above the moderate blockage level over multiple consecutive adsorption cycles, the first level of confirmation is determined to be passed. Based on the result that the degree of coking temperature rise and the degree of blockage level increase synchronously or remain in an abnormal state within multiple consecutive adsorption cycles, the second confirmation is determined to be passed. Based on the successful completion of both the first and second confirmations, a blockage confirmation signal is output.

[0014] Furthermore, the process of seamless switching of the adsorption tank includes: In response to the blockage confirmation signal, it is determined that the standby adsorption tank is in hot standby mode, and the inlet valve and outlet valve of the standby adsorption tank are opened. Based on the process stage status signal output by the adsorption control system, it is determined that the current regeneration switching window is open, and the standby adsorption tank switching operation is executed. Once the outlet flow rate of the backup adsorption tank has recovered to the range of the gas supply flow rate before the switchover, and the purity of the outlet inert gas has reached the preset process requirements, the inlet valve and outlet valve of the current adsorption tank are closed to complete the seamless switchover.

[0015] Furthermore, the process of determining the type of blockage and the corresponding solution includes: Obtain the first time point at which the coking temperature rise becomes abnormal and the second time point at which the differential pressure signal becomes abnormal, and compare the chronological relationship between the first time point and the second time point; If the first time point is earlier than the second time point, it is determined to be a coking blockage, and a disposal suggestion to open the tank and remove the coking layer is output. If the second time point is earlier than the first time point, it is determined to be a powder deposition type blockage, and a treatment suggestion of backflushing or sieving the adsorbent is output; If the time difference between the first time point and the second time point is less than a preset time window, it is determined to be a mixed blockage, and a treatment suggestion of replacing the entire adsorbent is output.

[0016] Compared with existing technologies, the advantages of this invention are as follows: By setting up dedicated measuring points for distributor differential pressure and inlet differential pressure in the inlet section, this invention constructs a multi-level differential pressure monitoring architecture, thereby extending the monitoring focus from the main inlet and outlet of the tank to areas prone to blockage, thus capturing abnormal signals in the early stages of blockage development. Simultaneously, this invention divides the operating conditions into supply and shutdown periods based on the gas supply status signal and calibrates differential pressure benchmark values ​​for each. Furthermore, by dynamically comparing the current cycle differential pressure recovery rate with the benchmark value, it distinguishes between reversible flow fluctuations and irreversible bed blockage, thereby eliminating the interference of periodic load changes on differential pressure judgment. Based on this, this invention utilizes the fact that the heat release from oil mist coking precedes the differential pressure. The invention utilizes the increased physical characteristics of the inlet section temperature rise and its rate of change as the first-level judgment signal, thereby triggering an early warning of accelerated coking before the pressure difference changes significantly, thus advancing the detection time of coking-type blockage anomalies to before the pressure difference increases significantly. Furthermore, the invention constructs a dual verification mechanism by continuously confirming the degree of blockage and confirming the consistency between the coking temperature rise and the direction of pressure difference change, thereby avoiding misjudgments caused by instantaneous sensor drift or occasional flow fluctuations. Finally, the invention identifies the blockage type online based on the chronological relationship between the coking temperature rise and the abnormal occurrence of pressure difference and outputs corresponding handling solutions, enabling maintenance personnel to take differentiated maintenance measures for different blockage causes. Attached Figure Description

[0017] Figure 1 This is a flowchart of the online monitoring method for blockage in an inert gas purification adsorption tank according to this embodiment; Figure 2 This is the logic diagram for determining the triggering of the coking acceleration warning signal in this embodiment; Figure 3 This is the logic diagram for determining the blockage confirmation signal in this embodiment; Figure 4 The logic diagram for determining the blockage type in this embodiment is shown. Detailed Implementation

[0018] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0019] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0020] Please see Figure 1 The diagram shown is a flowchart of an online monitoring method for clogging in an inert gas purification adsorption tank according to this embodiment. This embodiment provides an online monitoring method for clogging in an inert gas purification adsorption tank, including: Step S1: Based on the risk of oil mist impurity deposition on the feed gas inlet side of the inert gas purification adsorption tank in the stainless steel smelting supporting full extraction air separation unit, and the operating characteristics of the adsorption tank switching between adsorption, pressure equalization and regeneration according to the adsorption cycle, resulting in periodic changes in the inlet flow rate, the operating parameters and status signals of the inert gas purification adsorption tank are collected. Step S2: Based on the operating parameters and status signals, perform multi-condition calibration under clean conditions to determine the differential pressure reference value, temperature profile reference line and differential pressure recovery rate of the adsorption tank under gas supply and gas supply stop conditions. Step S3: Based on the temperature profile baseline, and combined with the inlet section temperature profile signal in the operating parameters and status signals, determine the degree of coking temperature rise in the inlet section, and determine the coking acceleration warning signal according to the rate of change of the degree of coking temperature rise. Step S4: In response to the coking acceleration warning signal being in a triggered state, and in combination with the differential pressure signal, periodic gas supply status signal and differential pressure reference value in the operating parameters and status signals, determine the distributor blockage confirmation signal; Step S5: In response to the distributor blockage confirmation signal being in a triggered state, the blockage level is determined by combining the operating parameters and the differential pressure signal in the status signal, the periodic gas supply status signal, the differential pressure reference value, and the differential pressure recovery rate of the reference period. Step S6: Based on the level of blockage and the degree of coking temperature rise, determine the blockage confirmation signal; Step S7: In response to the blockage confirmation signal being in a triggered state, perform uninterrupted switching of the adsorption tank, and determine the blockage type and handling plan based on the sequential relationship between the degree of coking temperature rise and the abnormal occurrence of the differential pressure signal.

[0021] Specifically, this invention constructs a multi-level differential pressure monitoring architecture by setting dedicated measuring points for distributor differential pressure and inlet section differential pressure in the inlet section. This extends monitoring from the main inlet and outlet of the tank to areas prone to blockage, allowing for the capture of abnormal signals in the early stages of blockage development. Simultaneously, based on the gas supply status signal, this invention divides the operating conditions into gas supply periods and gas supply stop periods, and calibrates differential pressure benchmark values ​​for each. By dynamically comparing the current cycle differential pressure recovery rate with the benchmark value, it distinguishes between reversible flow fluctuations and irreversible bed blockage, thereby eliminating the interference of periodic load changes on differential pressure judgment. Furthermore, this invention utilizes the physical characteristic that the exothermic reaction of oil mist coking precedes the increase in differential pressure. This invention uses the temperature rise amplitude and rate of change at the inlet section as the first-level judgment signal, thereby triggering an early warning of accelerated coking before the pressure difference changes significantly, thus advancing the detection time of coking-type blockage to before the pressure difference increases significantly. In addition, this invention constructs a dual verification mechanism by continuously confirming the degree of blockage and confirming the consistency between the direction of coking temperature rise and pressure difference change, thereby avoiding misjudgments caused by instantaneous sensor drift or occasional flow fluctuations. Finally, this invention identifies the blockage type online based on the chronological relationship between the abnormal occurrence of coking temperature rise and pressure difference and outputs corresponding handling solutions, enabling maintenance personnel to take differentiated maintenance measures for different causes of blockage.

[0022] In this embodiment, the process of collecting operating parameters and status signals includes: Based on the differential pressure sensors installed in the inlet and outlet pipelines of the adsorption tank, the pressure difference between the inlet and outlet pipelines is collected as the total inlet and outlet differential pressure signal.

[0023] Based on differential pressure sensors installed upstream and downstream of the inlet gas distributor, the pressure difference between the upstream and downstream of the distributor is collected as the distributor differential pressure signal. The two pressure taps of the distributor differential pressure sensor are connected to the pressure taps on the inlet side and the pressure taps on the outlet side of the distributor, respectively. The pressure tapping pipeline is connected to the pressure transmitter using a corrosion-resistant metal pipeline to avoid measurement drift caused by oil mist impurities in the raw gas.

[0024] Based on differential pressure sensors installed at the bottom of the ceramic ball layer and the middle of the bed in the inlet section, the pressure difference between the bottom of the ceramic ball layer and the middle of the bed is collected as the differential pressure signal of the inlet section.

[0025] Based on temperature sensors installed at multiple temperature measuring points along the axial direction of the inlet section, the temperature values ​​at each measuring point are collected as the axial temperature profile signal of the inlet section.

[0026] Based on the flow sensor installed in the inlet pipe, the instantaneous flow value of the inlet pipe is collected as the instantaneous inlet flow signal.

[0027] Collecting periodic gas supply state signals based on a communication connection with a periodic gas supply control system, wherein the periodic gas supply state signals include a gas supply period identifier and a gas supply stop period identifier.

[0028] In this embodiment, the adsorption tank is an inert gas purification device used in a full-extraction air separation facility supporting stainless steel smelting, in which an inlet distributor, a ceramic ball support layer and an adsorbent bed layer are sequentially arranged along the gas flow direction. After the raw material gas uniformly enters the adsorbent bed layer through the inlet distributor, impurity components are adsorbed and purified by the adsorbent. During long-term operation, oil mist components carried in the raw material gas undergo oxidative polymerization on the surface of the adsorbent in the inlet area, and combine with adsorbent powder to form deposits, which reduces the flow area in the inlet area, thereby causing a phenomenon of increased local pressure difference.

[0029] In this embodiment, the adsorption tank adopts a pressure swing adsorption purification structure, and the inlet raw material gas sequentially passes through the inlet pipeline, the gas distributor, the ceramic ball support layer and the adsorbent bed layer to complete impurity adsorption; the adsorbent bed layer comprises a molecular sieve adsorption layer for removing impurities such as water, carbon dioxide and hydrocarbons. During the operation of the adsorption tank, the steps of adsorption, pressure equalization, desorption and regeneration are sequentially executed according to the control program, wherein the inlet flow rate is the highest in the adsorption stage, and the gas flow rate decreases or flows reversely in the regeneration stage, so different process stages correspond to different pressure drop states.

[0030] In this embodiment, the temperature measuring points at the inlet section are arranged along the axial direction of the adsorption tank, and at least include positions at the top of the ceramic ball layer, the top of the adsorbent layer and the middle of the adsorbent layer, so as to obtain the temperature variation characteristics corresponding to the oil mist coking area, wherein The temperature measuring points are arranged at intervals along the central axis direction of the adsorption tank, and the spacing between the measuring points is determined according to the height of the adsorbent bed layer. In this embodiment, the range of 50mm to 200mm above the inlet distributor, the top of the ceramic ball support layer and the top area of the adsorbent bed layer are selected to be covered, so as to ensure that the local exothermic phenomenon generated by oil mist coking in the inlet area can be captured.

[0031] Specifically, this invention adds dedicated differential pressure measuring points upstream and downstream of the inlet gas distributor and between the bottom of the ceramic ball layer and the middle of the bed to acquire the distributor differential pressure signal and the inlet section differential pressure signal. This constructs a three-tiered differential pressure monitoring architecture: total differential pressure, distributor differential pressure, and inlet section differential pressure. The distributor and inlet section differential pressure signals originate directly from the inlet section deposition interface where blockage first occurs, and their relative variation is much greater than the total differential pressure. This allows monitoring to be located from the entire tank to the interior of the inlet section, solving the problem of coarse blockage location. Furthermore, this invention addresses the deficiency of differential pressure judgment caused by flow fluctuations under periodic variable load conditions. Instantaneous inlet flow signals are acquired by a flow sensor, and gas supply period identifiers and shutdown period identifiers are obtained through communication with the gas supply control system. This provides a basis for identifying operating conditions for subsequent time-segmented differential pressure benchmark values ​​and calculating periodic differential pressure recovery rates. This allows the differential pressure during gas supply and shutdown periods to be compared under their respective independent benchmarks, avoiding interference from flow fluctuations on the judgment results. In addition, this invention acquires temperature profile signals by axially deploying multiple temperature measuring points in the inlet section, providing data support for determining the degree of coking temperature rise. This allows the temperature signal to serve as another dimension of judgment independent of the differential pressure in subsequent serial step-by-step judgments.

[0032] In this embodiment, the process of determining the differential pressure reference value, the temperature profile reference line, and the differential pressure recovery rate over the reference period includes: Under clean conditions, the inlet flow rate of the adsorption tank is sequentially adjusted to each gas supply flow point and maintained in a stable manner. After the differential pressure reading stabilizes, the steady-state values ​​of the total differential pressure, distributor differential pressure, and inlet section differential pressure corresponding to each flow point are recorded to establish the correspondence between each differential pressure and flow rate. These values ​​serve as the reference values ​​for the total differential pressure, distributor differential pressure, and inlet section differential pressure at each flow point under gas supply conditions.

[0033] With the gas supply valve closed under clean conditions, the adsorption tank is put into a shutdown condition. After the differential pressure reading stabilizes, the steady-state values ​​of the total differential pressure, distributor differential pressure, and inlet section differential pressure are recorded as the reference values ​​of the total differential pressure, distributor differential pressure, and inlet section differential pressure under the shutdown condition.

[0034] Based on the temperature values ​​of each temperature measuring point in the inlet section collected under clean conditions and the reference temperature value of the middle section of the bed, the temperature difference between each measuring point and the middle section of the bed is calculated. The above difference is used as the temperature profile baseline. The baseline represents the temperature gradient that naturally exists in the inlet section under clean conditions due to the airflow passing through the adsorbent, and is used as a reference to determine the temperature rise amplitude.

[0035] Based on continuous tracking of no less than three complete adsorption cycles under clean conditions, the average pressure difference of the adsorption stage and the average pressure difference of the regeneration stage in each cycle are recorded respectively. The ratio of the average pressure difference of the regeneration stage to the average pressure difference of the adsorption stage in each cycle is calculated, and the average value of the ratio of each cycle is taken as the baseline cycle pressure difference recovery rate.

[0036] Specifically, this invention calibrates the total pressure difference, distributor pressure difference, and inlet section pressure difference benchmark values ​​at each flow point under clean conditions during gas supply. This allows the measured pressure difference during gas supply periods to be compared with the benchmark values ​​under the same flow conditions, thereby eliminating the interference of flow rate changes on pressure difference judgment and solving the problem of misjudgment of pressure difference due to flow rate fluctuations under variable load conditions. Simultaneously, this invention calibrates the pressure difference benchmark value for the gas supply shutdown condition under clean conditions, allowing the measured pressure difference during the shutdown period to be compared with the benchmark state when no airflow passes through. Furthermore, the degree of pressure difference drop can be used to determine whether irreversible blockage has occurred in the bed. This invention solves the problem of being unable to determine the reversibility of blockage during supply interruptions. Furthermore, by establishing a baseline temperature profile of the inlet section under clean conditions, this invention provides a reference for the quantitative determination of the inlet section temperature rise during subsequent operation, thus solving the problem of lacking a benchmark reference for the degree of coking temperature rise. In addition, by calibrating the differential pressure recovery rate of the benchmark cycle, this invention enables the degree of differential pressure recovery in each cycle during subsequent operation to be compared with the benchmark value, thereby distinguishing between normal differential pressure changes caused by flow fluctuations and irreversible differential pressure increases caused by bed blockage, solving the problem of being unable to distinguish between flow fluctuations and actual blockages under periodic variable load conditions.

[0037] In this embodiment, the process of determining the degree of coking temperature rise in the inlet section includes: The temperature values ​​of each temperature measuring point at the inlet section and the reference temperature value of the middle section of the bed are collected in real time. The difference between the temperature value of each measuring point and the reference temperature value of the middle section of the bed is calculated as the real-time temperature difference of each measuring point.

[0038] The real-time temperature difference at each measuring point is compared one by one with the reference difference value at the corresponding position in the temperature profile baseline. The increment of the real-time temperature difference at each measuring point relative to the corresponding reference difference value is calculated as the temperature rise amplitude at each measuring point.

[0039] The maximum temperature rise amplitude among all measuring points is taken as the degree of coking temperature rise in the inlet section. When the measuring point corresponding to the maximum value is located at the interface between the ceramic ball layer and the top adsorbent or within the top adsorbent layer, the temperature rise amplitude characterizes the degree of local temperature rise caused by the heat release of oil mist coking in the region, which serves as the basis for judging the triggering of the coking acceleration warning.

[0040] Specifically, this invention collects the real-time temperature difference between each temperature measuring point in the inlet section and the reference temperature in the middle section of the bed as the real-time temperature difference. It then compares the real-time temperature difference at each measuring point with the temperature profile baseline under clean conditions to obtain the temperature rise amplitude at each measuring point relative to the clean state. This allows for a quantitative assessment of temperature changes in the inlet section based on the clean state. Furthermore, this invention takes the maximum temperature rise amplitude among all measuring points as the degree of coking temperature rise in the inlet section and limits the location of the maximum value to the interface between the ceramic ball layer and the top adsorbent or within the top adsorbent layer. This focuses the degree of coking temperature rise on the core area of ​​the inlet section where the coking reaction is most likely to occur, thus avoiding interference from temperature fluctuations in other parts of the bed on the coking judgment. This provides an accurate and reliable basis for triggering subsequent coking acceleration warning signals.

[0041] Please see Figure 2 As shown, this is the logic diagram for determining the coking acceleration warning signal in this embodiment. In this embodiment, the process of determining the coking acceleration warning signal includes: The degree of coking temperature rise in the inlet section is recorded in real time over multiple consecutive adsorption cycles. The change in the degree of coking temperature rise between adjacent cycles is calculated. Based on the change in the degree of coking temperature rise between adjacent cycles over multiple consecutive adsorption cycles and the time interval between corresponding cycles, the rate of change of coking temperature rise per unit time is determined as a basis for judging whether coking is accelerating.

[0042] In response to the coking temperature rise reaching the coking degree alarm threshold, a coking acceleration warning signal is triggered. When the rate of change of the coking temperature rise reaches the coking rate alarm threshold, a coking acceleration warning signal is triggered.

[0043] In this embodiment, the coking rate alarm threshold is determined based on the upper limit of the natural fluctuation range of the coking temperature rise over multiple consecutive cycles under clean conditions. A rate margin is added to the upper limit of the natural fluctuation range as the coking rate alarm threshold, wherein the rate margin is set according to the response characteristics of the adsorbent.

[0044] Specifically, after the equipment completes the replacement or regeneration of the adsorbent, the adsorption tank is run for no less than three complete adsorption cycles. Temperature change data at each temperature measuring point in the inlet section are collected, and the temperature rise fluctuation range under normal operating conditions is statistically analyzed. Temperature rise changes exceeding this fluctuation range are used as the basis for judging coking anomalies.

[0045] Specifically, this invention sets two independent judgment conditions: a coking degree alarm threshold and a coking rate alarm threshold. It employs logic that triggers a warning signal when either condition is met. The coking degree alarm threshold detects situations where the accumulated coking amount has reached a dangerous level, while the coking rate alarm threshold detects trends of rapid coking deterioration. These two conditions complement each other, thus avoiding missed detections that might occur when relying on only a single judgment condition. Simultaneously, this invention quantifies the coking development trend by recording the coking temperature rise in real time over multiple consecutive cycles and calculating its rate of change, providing a data foundation for rate threshold determination. Furthermore, the coking rate alarm threshold is determined by adding a rate margin to the upper limit of the natural fluctuation amplitude under clean conditions, ensuring that the threshold matches the background noise under actual working conditions and avoiding misjudgments caused by normal fluctuations, thus guaranteeing the reliability of the warning signal triggering.

[0046] In this embodiment, the process of determining the distributor blockage confirmation signal includes: The current state of the adsorption or regeneration stage is determined based on the process stage status signal output by the adsorption control system.

[0047] During the adsorption phase, based on the current measured flow rate, the distributor differential pressure reference value corresponding to the flow rate point is found from the gas supply condition differential pressure reference value. The difference between the measured distributor differential pressure and the reference value is calculated as the degree of distributor differential pressure deviation during the adsorption phase. When the measured distributor differential pressure exceeds the distributor differential pressure reference value of the corresponding flow rate point under the gas supply condition by an amount that reaches the distributor differential pressure deviation threshold during the adsorption phase, a distributor blockage confirmation signal is triggered.

[0048] During the regeneration phase, the difference between the measured distributor differential pressure and the benchmark value under the shutdown condition is used as a reference. This difference is used as the degree of distributor differential pressure deviation during the regeneration phase. When the measured distributor differential pressure exceeds the benchmark value under the shutdown condition by a certain amount, the distributor differential pressure deviation threshold during the regeneration phase is reached, triggering a distributor blockage confirmation signal.

[0049] In this embodiment, the distributor differential pressure deviation threshold during the adsorption stage is determined based on the noise fluctuation range of the distributor differential pressure signal corresponding to each flow point under the gas supply condition in the clean state, and the distributor differential pressure deviation threshold during the regeneration stage is determined based on the noise fluctuation range of the distributor differential pressure signal under the shutdown condition in the clean state.

[0050] In this embodiment, all alarm thresholds are obtained through data calibration under normal operating conditions of the equipment. Specifically, after the adsorbent tank has completed adsorbent loading and stabilized operation, normal operating data is continuously collected for no less than 72 hours. The differential pressure fluctuation range and temperature fluctuation range corresponding to different process stages are statistically analyzed. The upper limit of the normal fluctuation range is used as the basic threshold, and it is corrected in combination with the allowable differential pressure of the equipment and the maximum pressure drop requirements provided by the adsorbent manufacturer.

[0051] Specifically, this invention addresses the problem of early blockage in the inlet section caused by interference from pressure drop in other areas of the bed, by setting dedicated differential pressure measuring points upstream and downstream of the distributor and comparing the gas supply period and the gas supply stop period with the reference values ​​under their respective operating conditions. This allows for the independent capture of resistance changes in the distributor, a region prone to blockage. Specifically, the gas supply period determination detects whether the distributor channel has undergone substantial narrowing during normal gas flow, while the gas supply stop period determination detects whether the differential pressure can recover to a clean state level after the gas flow stops. The combination of these two methods distinguishes between reversible deposition and irreversible blockage, avoiding misjudgments that may occur when single-condition judgment is used due to flow fluctuations or insufficient gas supply. Furthermore, the differential pressure deviation thresholds for the adsorption and regeneration stages are determined based on the noise fluctuation range of the corresponding operating condition signals under clean conditions, ensuring that alarm limits match the actual signal background and preventing frequent false triggers due to normal fluctuations. The adsorption and regeneration stages employ OR logic triggering, ensuring timely detection of any abnormalities occurring during or after operation of the distributor.

[0052] In this embodiment, the process of determining the level of congestion includes: The current state of the adsorption or regeneration stage is determined based on the process stage status signal output by the adsorption control system.

[0053] During the adsorption stage, based on the current measured flow rate, the total pressure difference benchmark value and the inlet section pressure difference benchmark value corresponding to the flow rate point are found from the gas supply condition pressure difference benchmark value. The difference between the measured total pressure difference and the total pressure difference benchmark value is calculated as the degree of deviation of the total pressure difference, and the difference between the measured inlet section pressure difference and the inlet section pressure difference benchmark value is calculated as the degree of deviation of the inlet section pressure difference.

[0054] During the regeneration phase, the total differential pressure benchmark value under the shutdown condition and the inlet section differential pressure benchmark value are used as references. The difference between the measured total differential pressure and the total differential pressure benchmark value is calculated as the degree of deviation of the total differential pressure, and the difference between the measured inlet section differential pressure and the inlet section differential pressure benchmark value is calculated as the degree of deviation of the inlet section differential pressure.

[0055] Calculate the ratio of the average pressure difference during the regeneration phase to the average pressure difference during the adsorption phase in the current cycle, and use this ratio as the pressure difference recovery rate for the current cycle.

[0056] The current cycle differential pressure recovery rate is compared with the reference cycle differential pressure recovery rate, and the increment of the current cycle differential pressure recovery rate relative to the reference cycle differential pressure recovery rate is calculated as the degree of deviation of the cycle differential pressure recovery rate.

[0057] At the same time, the degree of pressure difference deviation at the inlet section is used to determine whether the blockage is concentrated in the inlet area; when the degree of pressure difference deviation at the inlet section and the degree of total pressure difference deviation both reach the corresponding level range, the blockage level determination result is improved.

[0058] In response to the total differential pressure deviation being lower than the total differential pressure deviation threshold during the adsorption phase, and the deviation of the periodic differential pressure recovery rate being within the allowable fluctuation range of the baseline periodic differential pressure recovery rate, the blockage level is determined to be mild.

[0059] In response to the total differential pressure deviation reaching the total differential pressure deviation threshold of the adsorption stage but below the total differential pressure deviation threshold of severe blockage, or the deviation of the cycle differential pressure recovery rate exceeding the allowable fluctuation range of the baseline cycle differential pressure recovery rate, the blockage level is determined to be moderate.

[0060] When the total differential pressure deviation reaches or exceeds the total differential pressure deviation threshold for severe blockage, the blockage level is determined to be severe.

[0061] In this embodiment, mild blockage corresponds to an increase of 5% to 15% in the inlet pressure differential relative to the baseline value; moderate blockage corresponds to an increase of 15% to 30% in the inlet pressure differential and a decrease in the cycle recovery rate exceeding the normal fluctuation range; and severe blockage corresponds to an increase of more than 30% in the inlet pressure differential or reaching the maximum allowable pressure differential limit of the equipment.

[0062] In this embodiment, a mild blockage level corresponds to a state where the inlet section resistance increases slightly but can recover to the normal range during the regeneration stage; a moderate blockage level corresponds to a state where the inlet section resistance continues to increase and the recovery ability during the regeneration stage decreases; and a severe blockage level corresponds to a state where the inlet section resistance reaches the upper limit of the equipment's allowable operating range, requiring switching maintenance.

[0063] In this embodiment, the total pressure difference deviation threshold during the adsorption stage is determined based on the noise fluctuation range of the total pressure difference signal corresponding to each flow point under the clean state gas supply condition, so as to determine whether the deviation of the measured total pressure difference from the benchmark value during the gas supply period has reached the standard that requires further judgment.

[0064] In this embodiment, the allowable fluctuation range of the baseline cycle differential pressure recovery rate is determined based on the natural fluctuation amplitude of the cycle differential pressure recovery rate during three consecutive gas supply cycles and the shutdown cycle under clean conditions, in order to determine whether the deviation of the current cycle differential pressure recovery rate from the baseline value has exceeded the normal fluctuation range.

[0065] In this embodiment, the total pressure difference deviation threshold for severe blockage is determined based on the maximum allowable operating pressure difference under the design conditions of the adsorption tank, in order to determine whether the degree of deviation of the total pressure difference has reached a dangerous level that requires immediate action.

[0066] Specifically, this invention combines the deviation of total differential pressure, the deviation of inlet differential pressure, and the deviation of periodic differential pressure recovery rate to reflect the overall increase in bed resistance, whether blockage is concentrated in the inlet section, and whether the differential pressure can be recovered during the regeneration stage. It comprehensively determines the degree of blockage from three dimensions: resistance increase, blockage location, and reversibility, avoiding misjudgments that may occur under conditions of flow fluctuations or insufficient regeneration, where a single parameter is used. The deviations in the three dimensions correspond to baseline values ​​under clean conditions. An adaptive comparison method is used to eliminate interference from periodic load changes on the measurement signal, ensuring that the deviation accurately reflects the bed state under different operating conditions. Furthermore, this invention constructs a complete judgment chain from anomaly detection to degree confirmation through multi-parameter fusion. This ensures that the identification of blockage status does not rely on a single threshold trigger but is based on cross-validation of multi-dimensional signals, maintaining reliability of the judgment results under varying load conditions and sensor signal fluctuations.

[0067] Please see Figure 3 As shown, this is the logic diagram for determining the blockage confirmation signal in this embodiment. In this embodiment, the process of determining the blockage confirmation signal includes: Within at least three consecutive adsorption cycles, the degree of blockage in each cycle is recorded in real time. If the degree of blockage is not lower than moderate blockage in all cycles, the first confirmation is passed. If the degree of blockage drops to mild in any cycle, the first confirmation is interrupted and the distributor differential pressure status is re-monitored.

[0068] The system acquires the changes in the coking temperature rise and blockage level over multiple consecutive adsorption cycles. If both continue to rise or remain in an abnormal state, the second confirmation is passed. If the changes in the two are inconsistent, it is determined that the sensor or measurement signal may be abnormal, and the final operation is not triggered.

[0069] Based on the successful completion of both the first and second confirmations, a blockage confirmation signal is output.

[0070] Specifically, this invention establishes a first level of confirmation, requiring the blockage level to remain consistently above moderate for multiple consecutive cycles. Confirmation is only passed when all cycles meet this condition. If the level drops to mild in any cycle, the process is interrupted and re-monitored. This prevents single pressure fluctuations from directly triggering the final operation, resolving the issue of false triggering caused by occasional spikes. Simultaneously, this invention establishes a second level of confirmation, requiring the coking temperature rise to be in the same direction as the blockage level. If the directions are inconsistent, the sensor or measurement signal is considered abnormal, preventing the final operation from being triggered. This allows temperature and pressure signals to mutually verify each other, resolving the issue of misjudgment caused by single sensor drift. Furthermore, this invention outputs a blockage confirmation signal only after both levels of confirmation have passed. This ensures the output signal undergoes both continuous verification over time and consistency verification at the sensor level, enabling reliable confirmation results even under varying load conditions and fluctuating sensor signals.

[0071] In this embodiment, the process of seamless switching of the adsorption tank includes: In response to the blockage confirmation signal, after confirming that the standby adsorption tank has completed regeneration and is in standby mode, that the inlet and outlet valves are closed and ready to be opened immediately, and that the pressure inside the tank matches the pressure of the current gas supply system, the inlet and outlet valves of the standby adsorption tank are opened.

[0072] The system determines whether the gas supply is currently in a shutdown window based on the periodic gas supply status signal. If the gas supply is currently in a gas supply cycle, it waits until the shutdown window is reached before performing the switching operation.

[0073] When performing the switching operation, the outlet valve of the standby adsorption tank is opened at a set rate, and the outlet valve of the current adsorption tank is closed at the same rate, so that the two tanks maintain a short-term parallel operation during the switching process to maintain the stability of gas flow and pressure in the outlet pipeline.

[0074] In this embodiment, the set rate is determined based on the volume of the adsorption tank outlet pipeline and the allowable pressure fluctuation range downstream. The larger the outlet pipeline volume, the larger the buffer space when the two tanks are connected in parallel during the switching process, and the faster the switching rate can be adopted.

[0075] Once the outlet flow rate of the backup adsorption tank has recovered to the pre-switch gas supply flow rate range and the purity of the outlet inert gas meets the preset process requirements, the inlet and outlet valves of the current adsorption tank are closed to complete the seamless switching. Here, "flow rate meets the standard" means that the outlet flow rate of the backup adsorption tank has recovered to the pre-switch gas supply flow rate level, and "purity meets the standard" means that the purity of the outlet inert gas meets the lower limit of the process requirements. The current adsorption tank can only be closed after both are met to ensure that the gas supply flow rate and purity do not fluctuate after the switching.

[0076] In this embodiment, the preset process requirements are determined based on the minimum allowable requirements for the purity of inert gas in downstream gas-using equipment and are set by the production process specifications.

[0077] Specifically, this invention ensures that the backup adsorption tank has completed regeneration, pressurization, and outlet purity testing before switching, and is ready for immediate operation, with its pressure matching the current gas supply system. This allows the backup tank to be put into operation immediately, avoiding switching delays due to unmet conditions. Simultaneously, this invention selects a shutdown window for switching based on periodic gas supply status signals, limiting the switching operation to the period of lowest downstream gas demand, thus reducing disturbance to the gas supply system during the switching process. During switching, this invention synchronously opens the backup tank's outlet valve and closes the current tank's outlet valve at a set rate, ensuring smooth operation of both tanks during the switching process. The system maintains short-term parallel operation, where the set rate is determined based on the outlet pipeline volume and the downstream allowable pressure fluctuation range. The downstream allowable pressure fluctuation range is determined based on the allowable pressure change range during normal operation of the downstream gas-using equipment, ensuring that the valve action rate matches the actual pipeline characteristics and avoiding sudden pressure changes caused by excessively rapid action. Furthermore, this invention closes the current tank to complete isolation after the outlet flow of the backup tank returns to the level before switching and the outlet purity meets the process requirements, ensuring that the gas supply status after switching remains consistent with that before switching. Thus, the gas supply pipeline remains connected throughout the entire switching process, achieving adsorption tank switching without interrupting the gas supply.

[0078] Please see Figure 4 As shown, this is a logic diagram for determining the blockage type in this embodiment. In this embodiment, the process of determining the blockage type and the handling plan includes: After the coking acceleration warning signal is triggered, the coking temperature rise in the inlet section and the distributor pressure difference signal are monitored in real time. The time point when the coking temperature rise first exceeds the coking degree alarm threshold is recorded as the first time point, and the time point when the distributor pressure difference signal first exceeds the distributor pressure difference deviation threshold in the adsorption stage is recorded as the second time point. The order of the first time point and the second time point are compared.

[0079] The response point is earlier than the second time point, indicating a coking-type blockage. In this case, oil mist undergoes an oxidative polymerization reaction on the surface of the adsorbent in the inlet section to generate tar-like cementitious material. This reaction is exothermic, causing the temperature rise in the inlet section to precede the pressure difference rise. The blockage is a hard mixture of tar-like cementitious material and adsorbent powder, which cannot be removed by conventional backflushing. It is necessary to open the tank, remove the coking layer, and replenish the adsorbent. At this time, the suggestion to open the tank and remove the coking layer is output.

[0080] If the second time point is earlier than the first time point, it is determined to be a powder deposition type blockage. In this case, the powder generated by the upstream adsorbent due to mechanical wear migrates with the airflow to the surface of the distributor and accumulates. The process is a pure physical deposition without exothermic reaction. Therefore, the pressure difference rise occurs before the coking temperature rise. The blockage is a loose powder layer. At this time, the output is a treatment suggestion of backflushing or sieving the adsorbent. The powder is blown off the surface of the distributor by backflushing, or the machine is stopped, the powder is sieved out and then refilled.

[0081] In response to the simultaneous occurrence of anomalies at both the first and second time points, the blockage was determined to be a mixed-type blockage, where powder deposition and coking occurred simultaneously. The powder provided the framework for the coking, while the coking cemented the powder into hard lumps. The two blockage mechanisms promoted each other, and at this point, a treatment recommendation of replacing the entire adsorbent was issued.

[0082] In this embodiment, coking blockage is mainly caused by the oxidation and polymerization of high-boiling-point components such as oil mist in the feed gas in the inlet area of ​​the adsorbent to form cement; powder deposition blockage is mainly caused by the migration of fine powder generated by adsorbent wear and blockage of gas distribution channels.

[0083] Specifically, this invention distinguishes blockage types by comparing the time sequence of the coking temperature rise and the first abnormality in the differential pressure signal. Coking-type blockages, due to the exothermic reaction of oil mist oxidation and polymerization, cause the temperature rise before the differential pressure rises. Powder deposition-type blockages, due to the purely physical process of powder accumulation, cause the differential pressure rise before the temperature rise. This difference in physical mechanisms allows for online identification of blockage types. Furthermore, this invention outputs corresponding treatment plans for different identified blockage types, enabling maintenance personnel to directly take effective maintenance measures based on the blockage type. This avoids secondary problems caused by blind or inappropriate handling, improving efficiency and reducing maintenance costs.

[0084] The above description is merely a preferred embodiment of the present invention and is not intended to limit the 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 online monitoring of blockage in an inert gas purification adsorption tank, characterized in that, include: Based on the risk of oil mist impurity deposition on the feed gas inlet side of the inert gas purification adsorption tank in the stainless steel smelting and supporting full extraction air separation unit, and the operating characteristics of the adsorption tank that cause periodic changes in inlet flow rate due to the switching of adsorption, pressure equalization and regeneration according to the adsorption cycle, the operating parameters and status signals of the inert gas purification adsorption tank are collected. Based on the operating parameters and status signals, multi-condition calibration is performed under clean conditions to determine the differential pressure baseline, temperature profile baseline, and differential pressure recovery rate of the adsorption tank under gas supply and gas outage conditions. Based on the temperature profile baseline, and combined with the inlet section temperature profile signal in the operating parameters and status signals, the degree of coking temperature rise in the inlet section is determined, and a coking acceleration warning signal is determined according to the rate of change of the degree of coking temperature rise. In response to the coking acceleration warning signal being triggered, the distributor blockage confirmation signal is determined by combining the differential pressure signal in the operating parameters and status signals, the periodic gas supply status signal, and the differential pressure reference value. In response to the distributor blockage confirmation signal being triggered, the blockage level is determined by combining the operating parameters and the differential pressure signal in the status signal, the periodic gas supply status signal, the differential pressure reference value, and the differential pressure recovery rate of the reference period. Based on the level of blockage and the degree of coking temperature rise, a blockage confirmation signal is determined; In response to the blockage confirmation signal being triggered, the adsorption tank is switched without interruption, and the blockage type and treatment plan are determined based on the sequential relationship between the degree of coking temperature rise and the abnormality of the differential pressure signal.

2. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of collecting operating parameters and status signals includes: The total pressure difference signal between the inlet and outlet is collected based on the differential pressure sensors installed in the inlet and outlet pipelines of the adsorption tank. Differential pressure signals of the distributor are collected based on differential pressure sensors installed upstream and downstream of the inlet gas distributor; Differential pressure sensors located at the bottom of the ceramic ball layer and in the middle of the bed in the inlet section are used to collect differential pressure signals in the inlet section. Based on temperature sensors installed at multiple temperature measuring points along the axial direction of the inlet section, axial temperature profile signals of the inlet section are collected. Instantaneous inlet flow signals are collected based on a flow sensor installed in the inlet pipe; Based on the communication connection with the periodic gas supply control system, periodic gas supply status signals are collected.

3. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the differential pressure reference value, the temperature profile reference line, and the differential pressure recovery rate over the reference period includes: Based on the initial operating state where the adsorbent inside the adsorption tank does not coke or powder deposit under clean conditions, the inlet gas flow rate is adjusted to multiple preset gas supply flow rate points, and the corresponding total pressure difference, distributor pressure difference, and inlet section pressure difference under stable operating conditions are collected respectively. The correspondence between the gas supply flow rate and each pressure difference parameter is established, and the reference values ​​of the total pressure difference, distributor pressure difference, and inlet section pressure difference corresponding to each flow rate point under the gas supply condition are determined. Based on the clean state, the inlet gas supply valve of the adsorption tank is closed, so that the adsorption tank stops receiving gas and maintains a preset stable time. The total pressure difference, distributor pressure difference and inlet section pressure difference are collected under the condition of no airflow to determine the reference values ​​of the total pressure difference, distributor pressure difference and inlet section pressure difference under the shutdown condition. The temperature profile baseline is determined based on the temperature difference between each temperature measuring point in the inlet section and the temperature in the middle section of the bed. The baseline cycle pressure difference recovery rate is determined based on the ratio of the average pressure difference during the regeneration stage to the average pressure difference during the adsorption stage over multiple consecutive adsorption cycles.

4. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the degree of coking temperature rise in the inlet section includes: Based on the real-time temperature values ​​of each temperature measuring point in the inlet section and the reference temperature value in the middle section of the bed, the real-time temperature difference of each measuring point is determined. The real-time temperature difference at each measuring point is compared with the reference difference value at the corresponding position in the temperature profile baseline to determine the temperature rise amplitude at each measuring point. Based on the temperature rise distribution of each measuring point along the axial direction of the adsorption tank, the location of the maximum temperature rise and the corresponding temperature rise amplitude are determined, and the maximum temperature rise amplitude located in the interface area between the inlet ceramic ball layer and the top adsorbent layer or in the top adsorbent layer area is determined as the coking temperature rise degree of the inlet section.

5. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the early warning signal for accelerated coking includes: The rate of change of the coking temperature rise is determined by tracking the change trend of the coking temperature rise over multiple consecutive adsorption cycles. In response to the coking temperature rise reaching the coking degree alarm threshold, a coking acceleration warning signal is triggered. When the rate of change of the coking temperature rise reaches the coking rate alarm threshold, a coking acceleration warning signal is triggered.

6. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the distributor blockage confirmation signal includes: The current state of the adsorption or regeneration stage is determined based on the process stage status signal output by the adsorption control system. During the adsorption stage, the degree of deviation of the distributor pressure difference during the adsorption stage is determined based on the measured distributor pressure difference and the distributor pressure difference benchmark value at the corresponding flow point under the gas supply condition. During the regeneration phase, the degree of deviation of the distributor pressure difference during the regeneration phase is determined based on the measured distributor pressure difference and the distributor pressure difference benchmark value under the shutdown condition. In response to the distributor pressure difference deviation reaching the distributor pressure difference deviation threshold in the adsorption stage or the distributor pressure difference deviation reaching the distributor pressure difference deviation threshold in the regeneration stage, a distributor blockage confirmation signal is triggered.

7. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the level of congestion includes: The current state of the adsorption or regeneration stage is determined based on the process stage status signal output by the adsorption control system. The degree of deviation of the total pressure difference is determined based on the measured total pressure difference and the benchmark value of the total pressure difference corresponding to the current stage; The degree of deviation of the inlet section pressure difference is determined based on the measured inlet section pressure difference and the reference value of the inlet section pressure difference corresponding to the current stage. The pressure difference recovery rate for the current cycle is determined based on the ratio of the average pressure difference during the regeneration stage to the average pressure difference during the adsorption stage within the current adsorption cycle. Based on the comparison between the current cycle differential pressure recovery rate and the reference cycle differential pressure recovery rate, the degree of deviation of the cycle differential pressure recovery rate is determined; Based on the deviation of the total differential pressure, the deviation of the inlet differential pressure, and the deviation of the periodic differential pressure recovery rate, the overall flow resistance change state of the adsorption tank, the local resistance change state of the inlet section, and the resistance recovery capability during the regeneration stage are determined respectively, and the blockage level is determined according to the corresponding judgment results of the three.

8. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the blockage confirmation signal includes: Based on the result that the blockage level is consistently at or above the moderate blockage level over multiple consecutive adsorption cycles, the first level of confirmation is determined to be passed. Based on the result that the degree of coking temperature rise and the degree of blockage level increase synchronously or remain in an abnormal state within multiple consecutive adsorption cycles, the second confirmation is confirmed to be passed. Based on the successful completion of both the first and second confirmations, a blockage confirmation signal is output.

9. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of seamless switching of the adsorption tank includes: In response to the blockage confirmation signal, it is determined that the standby adsorption tank is in hot standby mode, and the inlet valve and outlet valve of the standby adsorption tank are opened. Based on the process stage status signal output by the adsorption control system, it is determined that the current regeneration switching window is open, and the standby adsorption tank switching operation is executed. Once the outlet flow rate of the backup adsorption tank has recovered to the range of the gas supply flow rate before the switchover, and the purity of the outlet inert gas has reached the preset process requirements, the inlet valve and outlet valve of the current adsorption tank are closed to complete the seamless switchover.

10. The online monitoring method for blockage in an inert gas purification adsorption tank according to claim 1, characterized in that, The process of determining the type of blockage and the corresponding solution includes: Obtain the first time point at which the coking temperature rise becomes abnormal and the second time point at which the differential pressure signal becomes abnormal, and compare the chronological relationship between the first time point and the second time point; If the first time point is earlier than the second time point, it is determined to be a coking blockage, and a disposal suggestion to open the tank and remove the coking layer is output. If the second time point is earlier than the first time point, it is determined to be a powder deposition type blockage, and a treatment suggestion of backflushing or sieving the adsorbent is output; If the time difference between the first time point and the second time point is less than a preset time window, it is determined to be a mixed blockage, and a treatment suggestion of replacing the entire adsorbent is output.

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