Liquid level prediction and alarm method for gas-liquid separator under sloshing condition

Abstract

The invention provides a liquid level prediction and alarm method for a gas-liquid separator under a sloshing condition. The liquid level prediction and alarm method comprises the following steps: arranging a plurality of liquid level meters at different positions of the gas-liquid separator; liquid level data of each position are collected in real time through a liquid level meter; according to the collected liquid level data, weighting or integrating the data of each liquid level meter according to the sectional area to obtain the total volume of liquid in the gas-liquid separator; calculating a liquid level value in a static state according to the calculated total volume and the sectional area of the gas-liquid separator; and comparing the calculated static liquid level value with preset upper and lower limit liquid level values, and carrying out alarm judgment. According to the method, the interference of liquid level fluctuation caused by sloshing on an alarm system can be effectively eliminated, so that false alarm is avoided, normal operation of the gas-liquid separator is ensured, and the stability and safety of the system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid level prediction and alarm, and specifically, to a liquid level prediction and alarm method for a gas-liquid separator under sloshing conditions. Background Art

[0002] In the process of hydrogen production by electrolyzing water, the gas-liquid separator is one of the core devices. Its main function is to separate the hydrogen and oxygen generated by electrolysis and ensure the normal operation of the device by maintaining a certain liquid level. Specifically, the gas-liquid separator needs to avoid water quality pollution caused by liquid backflow or potential safety hazards caused by gas mixing. At the same time, in order to monitor and control the liquid level, the gas-liquid separator usually has upper and lower liquid level warning lines. When the liquid level exceeds the upper limit, a liquid carry-over accident may occur, and when the liquid level is lower than the lower limit, phenomena such as high and low pressure gas leakage may occur. When the liquid level exceeds the warning range, the system will trigger an alarm signal to indicate a possible abnormality.

[0003] However, in some special application scenarios such as offshore floating wind power hydrogen production systems, since the hydrogen production system is usually installed on a floating platform, under the dynamic influence of the external wind, wave and current environment, the platform is in an unstable state of tilt or sway for a long time, and the liquid inside the device will also fluctuate accordingly. Due to the existence of fluctuations, the liquid level will fluctuate violently up and down in a short period of time. Even if the actual liquid level remains within the safe range, some local liquid level values may still instantaneously exceed the upper and lower limits, thus triggering false alarms. Traditional liquid level monitoring methods are only based on the real-time data of single-point or local liquid level gauges, lacking a comprehensive understanding of the overall distribution state of the liquid, resulting in a relatively high probability of false judgment of the alarm system under sloshing conditions and may be difficult to meet actual requirements. Moreover, this false alarm of the liquid level caused by sloshing not only interferes with the normal operation of the device, but also may increase the complexity and cost of system maintenance. For example, each false alarm requires arranging personnel for inspection, resulting in a significant increase in the maintenance workload. In addition, frequent false alarms will affect the reliability of the device operation, and may prevent the system from detecting real abnormalities in time, thus bringing potential safety hazards.

[0004] At present, most of the solutions to the problem of false liquid level alarms in the industry are limited to improving the accuracy of liquid level gauges or adjusting the range of warning lines, but these methods cannot fundamentally solve the problem of liquid level fluctuations caused by wave sloshing. On the one hand, improving the accuracy of liquid level gauges may increase system costs, and on the other hand, expanding the warning line range may lead to a decrease in alarm sensitivity and an increase in the risk of missed alarms. Therefore, there is an urgent need for a new technical means that can comprehensively consider the actual changes in the liquid level of the gas-liquid separator under dynamic sloshing conditions, accurately predict the liquid level state as a whole, and avoid the occurrence of false alarms. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a liquid level prediction and alarm method for a gas-liquid separator under sloshing conditions. The method of the present invention can effectively eliminate the interference of the liquid level fluctuation caused by sloshing to the alarm system, thereby avoiding false alarms, ensuring the normal operation of the gas-liquid separator, and improving the stability and safety of the system.

[0006] To solve the above problems, the technical solution of the present invention is as follows:

[0007] A liquid level prediction and alarm method for a gas-liquid separator under sloshing conditions, comprising the following steps:

[0008] Arrange a number of liquid level gauges at different positions of the gas-liquid separator;

[0009] Collect the liquid level data of each position in real time through the liquid level gauges;

[0010] According to the collected liquid level data, weight or integrate the data of each liquid level gauge according to the cross-sectional area to obtain the total volume of the liquid in the gas-liquid separator;

[0011] Deduce the liquid level value in the static state according to the calculated total volume and the cross-sectional area of the gas-liquid separator;

[0012] Compare the deduced static liquid level value with the preset upper and lower limit liquid level values to make an alarm judgment.

[0013] Preferably, the step of arranging a number of liquid level gauges at different positions of the gas-liquid separator specifically includes: arranging a number of liquid level gauges evenly at different positions of the gas-liquid separator, and the number n of the liquid level gauges is determined according to the geometric characteristics and dynamic characteristics of the separator.

[0014] Preferably, the step of collecting the liquid level data of each position in real time through the liquid level gauges specifically includes: collecting the liquid level data h i (t) of each position in real time through the liquid level gauges, where i represents the liquid level gauge number (i = 1, 2,..., n), and t represents time.

[0015] Preferably, the step of weighting and integrating the data of each liquid level gauge according to the cross-sectional area according to the collected liquid level data to obtain the total volume of the liquid in the gas-liquid separator specifically includes: assuming that the cross-sectional area of the separator is A, the total volume V(t) can be calculated by the following formula: When the platform sloshing is too violent, a phenomenon similar to wave breaking may occur inside the separator, and multiple liquid level values h ij (t) may be read by the liquid level gauges at the breaking point, where j represents the liquid level value number (j = 1, 2,..., m). It is considered that hi1 > hi2 >... > him, then there are two ways to calculate the total volume V(t):

[0016] Preferably, the step of calculating the liquid level value at rest by inferring from the calculated total volume and the cross-sectional area of the gas-liquid separator specifically includes: dividing the calculated total volume V(t) by the cross-sectional area A of the gas-liquid separator to infer the liquid level value H(t) at rest:

[0017] Preferably, the step of comparing the inferred static liquid level value with the preset upper and lower limit liquid level values for alarm judgment specifically includes: comparing the inferred static liquid level value with the preset upper and lower limits of the liquid level min(H) and max(H):

[0018] if H min (t)<(1 + a)min(H) or H max (t)>(1 - a)max(H), then trigger an alarm.

[0019] where a represents a safety factor; if the liquid level value exceeds the set range of the upper and lower limit liquid level values, an alarm signal is triggered to indicate that there may be an abnormal situation; otherwise, the normal state is maintained.

[0020] Compared with the prior art, the present invention reasonably arranges a number of liquid level gauges in the gas-liquid separator, real-time collects the liquid level data at different positions, calculates the total volume of the liquid inside the separator by means of weighting or integration, and then infers the liquid level value at rest in combination with the total volume of the internal liquid and the cross-sectional area of the separator, and makes an alarm judgment according to the set upper and lower limit liquid level values. The method of the present invention can effectively eliminate the interference of the liquid level fluctuation caused by sloshing to the alarm system, thereby avoiding false alarms and ensuring the normal operation of the gas-liquid separator, and improving the stability and safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] By reading the following detailed description of the non-limiting embodiments with reference to the accompanying drawings, other features, objects and advantages of the present invention will become more apparent:

[0022] Figure 1 It is a flow block diagram of the liquid level prediction and alarm method for the gas-liquid separator under sloshing conditions of the present invention;

[0023] Figure 2 It is a case diagram of the liquid level prediction and alarm method for the gas-liquid separator in a specific embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all belong to the protection scope of the present invention.

[0025] The present invention provides a liquid level prediction and alarm method for a gas-liquid separator under sloshing conditions, which is used for liquid level prediction and alarm of a gas-liquid separator under sloshing conditions, and is applicable to the gas-liquid separator in an offshore floating wind power hydrogen production system, to solve the problem of false liquid level alarms caused by sloshing. Specifically, as Figure 1 shown, the method includes the following steps:

[0026] S1: Arrange a number of liquid level gauges at different positions of the gas-liquid separator;

[0027] Specifically, a number of liquid level gauges are evenly arranged at different positions of the gas-liquid separator. Assuming that the cross-section of the separator is circular, the liquid level gauges should be evenly distributed at a reasonable interval to ensure that the overall state of the liquid in the separator can be monitored. The number n of liquid level gauges is determined according to the geometric characteristics and dynamic characteristics of the separator.

[0028] S2: Real-time collect the liquid level data at each position through the liquid level gauges;

[0029] Specifically, the liquid level data h i (t) at each position is real-time collected through the liquid level gauges, where i represents the liquid level gauge number (i = 1, 2,..., n), and t represents time. Record the liquid level values of each liquid level gauge to reflect the fluctuation of the liquid inside the gas-liquid separator.

[0030] S3: According to the collected liquid level data, weight or integrate the data of each liquid level gauge according to the cross-sectional area to obtain the total volume of the liquid in the gas-liquid separator;

[0031] Specifically, according to the collected liquid level data, weight the data of each liquid level gauge according to the cross-sectional area to obtain the total volume of the liquid in the separator. Assuming that the cross-sectional area of the separator is A, the total volume V(t) can be calculated by the following formula:

[0032]

[0033] Particularly, when the platform sloshing is too violent, a phenomenon similar to wave breaking may occur inside the separator, and multiple liquid level values h ij (t) may be read by the liquid level gauges at the breaking point, where j represents the liquid level value number (j = 1, 2,..., m). It is considered that hi1 > hi2 >... > him. Then, for conservative consideration, there are two ways to calculate the total volume V(t):

[0034]

[0035] S4: Calculate the liquid level value at rest by inferring from the calculated total volume and the cross-sectional area of the gas-liquid separator;

[0036] Specifically, divide the calculated total volume V(t) by the cross-sectional area A of the gas-liquid separator to infer the liquid level value H(t) at rest:

[0037]

[0038] The liquid level value at rest is the liquid level value that the separator should have without external disturbance, and it is an important basis for judging whether the separator is within the normal working range.

[0039] S5: Compare the inferred liquid level value at rest with the preset upper and lower limit liquid level values for alarm judgment.

[0040] Specifically, compare the inferred liquid level value at rest with the preset upper and lower limits of the liquid level min(H) and max(H):

[0041] if H min (t)<(1 + a)min(H) or H max (t)>(1 - a)max(H), then trigger an alarm.

[0042] Considering a certain safety margin, the liquid level warning range under sloshing conditions should be smaller than that under static conditions, where a represents the safety factor. If the liquid level value exceeds the set upper and lower limit liquid level value range, an alarm signal is triggered to indicate that there may be an abnormal situation. Otherwise, maintain the normal state.

[0043] Figure 2 Shown is a specific embodiment implemented according to the method of the present invention. In this embodiment, the diameter of the gas-liquid separator is 0.45 m, and a total of 7 liquid level gauges are evenly distributed inside, and the measured liquid level values are shown in Table 1 below.

[0044] Liquid level gauge 1 2 3 4 5 6 7 Liquid level value / m 0.508 0.864 0.897 0.752 0.976 0.814 0.616

[0045] Table 1

[0046] Calculate the total liquid volume as 0.123 m based on the above measured liquid level values 3, it is calculated that the static liquid level is 0.775 m. If the safety factor a = 0.1 and the alarm warning line range is 0.6 m to 0.9 m, then the liquid level value is within the safe range (0.66 m to 0.81 m). The liquid level value measured by the liquid level gauge 1 is lower than the lower limit, and the liquid level value of the liquid level gauge 5 is higher than the upper limit. According to the traditional method, there is a possibility of false alarm of the gas-liquid separator at this moment. However, according to the method described in the present invention, the separator liquid level is within the safety warning range and normal operation is allowed.

[0047] In summary, the method of the present invention can eliminate the interference of the liquid level fluctuation caused by sloshing to the alarm system through the comprehensive processing and prediction of the liquid level data, and avoid the occurrence of false alarms. The prediction of the liquid level value not only depends on the measurement results of a single liquid level gauge, but also considers the data of multiple points for weighted calculation, so as to provide a more accurate liquid level estimation. The method of the present invention can effectively eliminate the interference of the liquid level fluctuation caused by sloshing to the alarm system, thereby avoiding the occurrence of false alarms, ensuring the normal operation of the gas-liquid separator, and improving the stability and safety of the system.

[0048] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A method for predicting and alarming the liquid level of a gas-liquid separator under sloshing conditions, characterized in that: The method comprises the following steps: Arrange several liquid level gauges at different positions of the gas-liquid separator; Collect the liquid level data of each location in real time through the liquid level meter; Based on the collected liquid level data, the data of each liquid level meter is weighted or integrated according to the cross-sectional area to obtain the total volume of the liquid in the gas-liquid separator; The liquid level value in the static state is calculated based on the calculated total volume and the cross-sectional area of ​​the gas-liquid separator; The calculated static liquid level value is compared with the preset upper and lower limit liquid level values ​​to make an alarm judgment.

2. The method for predicting and alarming the liquid level of a gas-liquid separator under sloshing conditions according to claim 1, characterized in that: The step of arranging a plurality of liquid level gauges at different positions of the gas-liquid separator specifically includes: evenly arranging a plurality of liquid level gauges at different positions of the gas-liquid separator, wherein the number n of the liquid level gauges is determined according to the geometric characteristics and dynamic characteristics of the separator.

3. The method for predicting and alarming the liquid level of a gas-liquid separator under sloshing conditions according to claim 1, characterized in that: The step of collecting the liquid level data of each position in real time by using the liquid level meter specifically includes: collecting the liquid level data of each position in real time by using the liquid level meter i (t), where i represents the level gauge number (i=1, 2,…, n), and t represents time.

4. The method for predicting and alarming the liquid level of a gas-liquid separator under sloshing conditions according to claim 3, characterized in that: The step of weighting or integrating the data of each liquid level meter according to the cross-sectional area based on the collected liquid level data to obtain the total volume of the liquid in the gas-liquid separator specifically includes: assuming that the cross-sectional area of ​​the separator is A, the total volume V(t) can be calculated by the following formula: When the platform sways too violently, a phenomenon similar to wave breaking may occur inside the separator, and the level gauge may read multiple liquid level values ​​at the breaking point. ij (t), where j represents the level value number (j = 1, 2, ..., m), assuming that hi1>hi2>...>him, there are two ways to calculate the total volume V(t):

5. The method for predicting and alarming the liquid level of a gas-liquid separator under sloshing conditions according to claim 4, characterized in that: The step of calculating the liquid level value in a static state according to the calculated total volume and the cross-sectional area of ​​the gas-liquid separator specifically includes: dividing the calculated total volume V(t) by the cross-sectional area A of the gas-liquid separator to calculate the liquid level value H(t) in a static state:

6. The method for predicting and alarming the liquid level of a gas-liquid separator under sloshing conditions according to claim 1, characterized in that: The step of comparing the calculated static liquid level value with the preset upper and lower limit liquid level values ​​to make an alarm judgment specifically includes: comparing the calculated static liquid level value with the preset upper and lower limits of the liquid level min (H) and max (H): if H min (t)<(1+a)min(H)or H max (t)>(1-a)max(H),then trigger an alarm. Where a represents the safety factor; if the liquid level value exceeds the set upper and lower limit liquid level value range, an alarm signal is triggered to indicate that there may be an abnormal situation; otherwise, the normal state is maintained.

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