Development Of The Oil Field Heat Washover Process Temperature Monitoring System Based On Fiber-Optic Sensingtechnology

Oil-field heat washover is widely used in oil industry as a method of oil well wax cleaning. When heat washover operates, the temperature of the annular space between tubing and casing changes as the entry of external heat lotion, and the real-time temperature monitoring was always a problem. For a long time, lacking of access to real-time informatin about the temperature changes of heat washover, heat washover was usually inefficient, which resulted in the wax content of oil was too high, reducing the effective yield. And it also caused lots of replacements of tubings for wax-caused block, making the entire oil industry suffer huge economic losses. Therefore, it has become a serious problem how to monitor real-time temperature on heat washovering accurately.According to the characteristics of the environment of Daqing oil Field, this article proposed a fiber-optic distributed sensors to monitor the real-time distributed temperature changes in heat washover process, the main research work and the results are as follows:Firstly, analysed the fiber-optic sensor distributed monitoring process on temperature changes during heat washover.Second, compared three fiber-optic sensors including Brillouin sensors, Raman sensor and FBG by experiment, proving the choice of Raman scattering sensor sensor is reasonable.Finally, the temperature distribution can be known by FLUENT simulation, according to the environmenal characteristics of Daqing oil field, proposed a system of fiber-optic sensor net in which Raman sensors are fixed up along the tubing to establish one well demonstration project and monitor the real-time distributed temperature changes on heat washover, and completed the field experiments and results analysis.Real-time distributed temperature monitoring system based on fiber-optic sensor reflect the temperature changes in the heat washover process accurately, to provide the basis of improving heat washover, and reduce the economic loss caused by heat washover inefficience, so has a very important significance.