The Study On Improving The Mobility Of Fluid In Pipeline By Electrical Heating

With the development of electrical heating gathering, the oil gathering process ofelectrical heating has been widely by many domestic oilfields. The principle of the process is:the lower temperature oil, gas and water mixture from wellhead flow into the wellheadelectrical heater by its own pressure, then gathering and transportation after the temperaturereaches the required temperature of gathering oil. Electrical heating gathering is a dendriticpipeline network, the terminal well has a distance from the station, when the water content inoil well near the phase transition point, the wellhead back pressure of terminal well willsharply rise. In order to avoid this situation, measures should be taken to improve the mobilityof fluid in pipeline by electrical heating in the production. So the study on rheology ofemulsion of crude oil and the cycle controlled by time of electrical heating is very importantto improve the mobility of fluid in pipeline by electrical heating and the safety of the oilgathering pipeline.This paper firstly studies the formation of emulsion of the wellbore in the production, todetermine the degree of emulsification of the emulsion before flowing into the pipeline, tomake adequate preparations for the indoor simulation experiment; Secondly, to determine theinfluence of the emulsion stability through the indoor emulsion experiment, through the studyon the rheology of oil emulsion, we can determine the inversion point and the rheologicalproperties of crude oil emulsion of a block of Daqing Oilfield, the results provide thetheoretical basis of oil and gas gathering and transportation in the production; Thirdly, toconduct a field test referring the research of laboratory, to validate the conclusions of researchin the lab through analysis on the actual crude oil emulsion; Finally, to study the influence ofpoint temperature of intermittent heating on pipeline of gathering and transportation byelectrical heating, to determine the start and stop cycle by time controlled under differentconditions. Based on theory and practice, to find some methods to improve the mobility offluid in pipeline by electrical heating:(1)To dose in wellhead, and put the demulsifier in theannular space of the oil sleeve, to prevent emulsion formation.(2) To add water over the phasetransition point, lower viscosity, reduce the pressure loss.(3)To adapt electrical heating bytime controlled.(4)To improve the temperature of the transportation.