LNG storage tank perlite settlement monitoring system and method based on distributed optical fibers

Abstract

The invention relates to a LNG storage tank perlite settlement monitoring system and method based on distributed optical fibers. The system is characterized in that it comprises a plurality of distributed temperature-measuring optical fibers, an optical fiber junction box, a distributed optical fiber temperature-measuring host computer equipped with at least two channels, and a display screen host computer; respective distributed temperature-measuring optical fibers are laid on the inner wall(s) of one or more LNG storage tank outer tanks; the head ends and the tail ends of respective distributed temperature-measuring optical fibers are connected with the optical fiber junction box; the optical fiber junction box is connected with respective channels of the distributed optical fiber temperature-measuring host computer via the distributed optical fibers; and the distributed optical fiber temperature-measuring host computer performs dual-channel bidirectional transmission and demodulation on the head ends and the tail ends of respective distributed temperature-measuring optical fibers to obtain a final temperature measurement value, sends the final temperature measurement value to the display screen host computer for display via a TCP / IP communication interface, and sends the final temperature measurement value to a centralized control system for further processing via a standard communication interface. The system and method can be widely applied to the monitoring of LNG storage tank perlite settlement.

Description

technical field [0001] The invention relates to the technical field of LNG (liquefied natural gas) and LNG storage tanks, in particular to a perlite settlement monitoring system and method for LNG storage tanks based on distributed optical fibers. Background technique [0002] As an economical and efficient clean energy, the LNG industry is facing a golden period of development. A certain number and different scales of LNG storage tanks are involved in all links of the LNG industry chain, such as natural gas liquefaction plants, LNG carriers, LNG receiving stations, Small satellite stations and LNG filling stations, etc. Encouraged by my country's energy policy, China is continuing to increase the construction of LNG storage and transportation bases. Several large-scale LNG storage and transportation bases are being planned, and the number of LNG storage tanks in a single storage and transportation base can exceed 20. [0003] As a large-scale storage device for cryogenic l...

AI Technical Summary

Problems solved by technology

[0003] As a large-scale storage device for cryogenic liquids, the temperature of LNG stored inside is as low as -165°C. LNG storage tanks may leak under abnormal conditions such as overfilling and earthquakes. Once a leak occurs, if remedial measures are not taken in time, the overflowing LNG It will quickly evaporate into flammable and explosive gas, which may cause major safety accidents and cause immeasurable losses to personnel, buildings, and equipment around the LNG storage tank.

In addition, the annular space of the LNG storage tank is kept cold by filling perlite. As the operating years of the LNG storage tank increase, the perlite in the annular space of the LNG storage tank will gradually decrease. If it is not filled in time, the LNG in the inner tank will be cold. The amount will be quickly transmitted to the inner wall of the outer tank, directly affecting the structural characteristics of the outer tank lining and reinforced concrete of the outer tank, thus having an irreversible and significant impact on the safety of the LNG storage tank structure

At the same time, the external transfer of cooling capacity will reduce the cold insulation performance of LNG storage tanks, and the amount of evaporated gas will be too much, which will have a negative impact on production safety and economic benefits

[0004] The existing LNG storage tank perlite settlement monitoring system usually uses a point temperature sensor (RTD) for measurement, which has shortcomings such as limited number of laying points, difficulty in integrating and installing a large number of cables, and short service life. Therefore, it is urgent to propose a safer and more reliable monitoring system. LNG Storage Tank Perlite Settlement Monitoring System

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