The pipeline leakage monitoring system can adopt a distributed fiber optic temperature measurement method,
Pipeline transportation has the advantages of safety, efficiency, economy, and environmental protection. It can greatly reduce the transportation and replacement process, achieve continuous transportation, and has a large transportation volume, high efficiency, and is easy to achieve automated management. The transportation of strategic resources such as oil and natural gas, the transmission of cooling water for various power enterprises, and the heat transfer required for winter heating in the north are all of great significance. However, leakage accidents still occur from time to time due to pipeline aging, changes in geographical and climatic environments, and human damage. Establishing a monitoring system for pipelines and achieving real-time detection of pipeline leaks will minimize economic losses and resource waste, and minimize the occurrence of environmental pollution and safety accidents, which has extremely important practical significance.
However, due to the diversity and complexity of pipeline leak detection, there is currently no simple, fast, accurate, reliable, and universal pipeline leak detection method at home and abroad. At present, there are many methods for pipeline safety monitoring, including manual inspection, air sampling, tracer monitoring, magnetic flux leakage monitoring, ultrasonic monitoring, in pipe detection ball method, negative pressure wave monitoring, pressure gradient method, and fiber optic sensing monitoring. However, air sampling and manual observation methods cannot be used for continuous monitoring; The tracer monitoring method and magnetic flux leakage monitoring method are difficult to achieve online real-time monitoring of pipelines; The ultrasonic monitoring method has high accuracy, but is sensitive to the conveying medium and cannot monitor in real-time; The cost of the in pipe detection ball method is high, and the detection ball is easy to block the pipeline; The negative pressure wave monitoring method has small computational complexity and fast response time, but it requires that the leakage be sudden. If the leakage speed is slow and there is no obvious negative pressure wave, the method will fail.
Fiber optic sensing technology has many advantages such as high measurement sensitivity, resistance to electromagnetic interference, radiation, high pressure resistance, corrosion resistance, small size, and light weight. It is expected to solve the problems of low accuracy, inability to monitor online in real time, and susceptibility to interference. At the information processing end, based on the DTS sent
Decode the temperature distance curve to achieve precise positioning of temperature anomalies. At the same time, extract the signal intensity distribution information caused by the temperature field on each section of the optical fiber, and perform trend analysis on the gradient distribution and changes of the temperature field to improve the positioning accuracy of abnormal points. Accurately calculate the diffusion mode, diffusion direction, and diffusion speed of the leaked material, and improve the accuracy of predicting the leakage amount. The present invention achieves efficient detection, accurate positioning, and leakage trend judgment of pipeline leaks through online temperature monitoring of long-distance gas-liquid transportation pipelines.
(1) Based on the simulation model of temperature field distribution at different leakage points in gas-liquid transportation pipelines, combined with the temperature gradient field near the leakage point, comprehensively and systematically analyze the spatial and temporal information of the temperature field formed by the leakage in gas-liquid transportation pipelines.
(2) Breaking through the difficulty of long-distance distributed fiber optic temperature measurement, providing a new method for accurate identification technology of gas-liquid pipeline leakage under different interference conditions and related processes of sensor on-site deployment. Develop a real-time online monitoring system for long-distance distributed fiber optic gas-liquid transportation pipeline leaks, filling the gap in specialized equipment in this field in China.
(3) In response to the complex noise interference in the actual monitoring environment of gas-liquid transportation pipelines, as well as the high false alarm and false alarm rates of traditional signal processing techniques, combined with temperature statistical feature extraction technology, the pipeline temperature information is optimized and processed, and gradient field fitting is performed to improve the accuracy of gas-liquid transportation pipeline leakage monitoring, leak point positioning, and precise analysis of leakage trends.
Application of Distributed Fiber Optic Leakage Monitoring System
1. Oil pipeline leakage detection: By implementing temperature monitoring around optical cables, the purpose of oil pipeline leakage detection is achieved;
2. Abnormal alarm: When the detected temperature exceeds the set range, an alarm message will be prompted and operation suggestions will be given;
3. Differential temperature alarm: The alarm parameters support manual setting, output relay alarm signals and alarm positioning information, and achieve differential temperature alarm;
4. Alarm zone setting: The system can program the length and alarm points of the alarm area as a whole, and can be flexibly adjusted according to the on-site situation;
5. Data analysis: storing, querying, and analyzing historical data;
6. Remote access: The system can connect to industrial Ethernet and transmit data to various levels of management departments to achieve remote access.