The calculation of liquid temperature during the process of circulating warm liquid in oil well and online monitoring experiments based on Raman optical fiber

Deposition of paraffin is one of the major problems that restrict the stable and high production of an oil well. The method of circulating warm liquid is an effective way to remove paraffin in oil fields. The current difficulty lies in presetting parameters for the process of circulating warm liquid and the efficiency. To solve this problem, a model coupling heat and fluid during the process of circulating warm liquid is developed in this work. Liquid temperatures along the well depth are obtained according to the model. In comparison, the liquid temperature of a test well in Daqing Oilfield was monitored online using the Raman optical fiber monitoring system developed by the authors. The monitored temperatures are well suited to the values calculated using the developed model. The maximum deviation of the temperature is 3 °C. The parameters of circulating warm liquid can be optimized in the future according to the coupling model.