According to the
carbon dioxide concentration detection device based on
optical fiber sensing and the storage
monitoring system provided by the invention, the first
optical fiber sensing unit with a
modular structure is designed, so that the contact part of the sensitive
coating and the
optical fiber Bragg
grating can be independently maintained and replaced, and the optical
fiber reflection
wavelength drift caused by the CO2 concentration change in the environment can be accurately detected. Meanwhile, a
fiber bragg
grating which is not covered with a CO2 sensitive
coating is arranged as a reference, and
wavelength drift mainly generated by environmental interference factors is detected. The influence of environmental interference factors on the
wavelength drift of the CO2 optical
fiber sensor can be eliminated by calculating the wavelength drift distance of the two fiber bragg gratings and combining the
mathematical model of the wavelength drift distance and the CO2 concentration, and then the accurate CO2 concentration value is obtained. According to the invention, high-efficiency real-time monitoring of CO2 concentration in the geological storage process of CO2 is realized, and
data accuracy and reliability are ensured. Moreover, the
modular design facilitates the regular inspection and replacement of the sensor, prolongs the service life, reduces the maintenance cost, and is high in sensitivity, strong in stability, and good in
maintainability.