期刊名称:Bulletin of the Institute of Heat Engineering
印刷版ISSN:2083-4187
出版年度:2016
卷号:96
期号:4
页码:261
语种:English
出版社:Warsaw University of Technology
摘要:Oil plugging of downhole during oilfield development leads to a decline in well yield. A new plug removal method basedon pulsed high-voltage discharge technology was proposed in this paper to solve this plugging problem. A low-carbon steelhigh-pressure sealed drum was developed to simulate downhole operating environment with high static pressure. Four sealedcontact pins were designed on the drum cover. These pins were used to insert the high-voltage cable into drum body whileensuring the leakproofness of the drum. The maximum static pressure borne by the drum was 40 MPa. An experimentalsystem of pulsed high-voltage discharge was designed based on the drum. A platform for discharging experiment wasestablished according to the system principle diagram. The effects of variation in static pressure on discharging voltage,discharging current, critical breakdown field strength, discharging time and its data discretization, and other parameters weredetermined with water and crude oil as the discharging media. Experimental results indicate that increasing static pressureincreases discharging time, enhances pulsed discharging randomness, reduces strength of impact waves generated in thedischarging media, and weakens fracture-generating effect on the cement tube. Increasing the working voltage is necessaryto achieve better plug removal. However, the requirements for size, texture, and insulativity of a plug removal equipment arecorrespondingly elevated. This study provides a basis for the application of pulsed high-voltage discharge technology in oilreservoir plug removal.
其他摘要:Oil plugging of downhole during oilfield development leads to a decline in well yield. A new plug removal method based on pulsed high-voltage discharge technology was proposed in this paper to solve this plugging problem. A low-carbon steel high-pressure sealed drum was developed to simulate downhole operating environment with high static pressure. Four sealed contact pins were designed on the drum cover. These pins were used to insert the high-voltage cable into drum body while ensuring the leakproofness of the drum. The maximum static pressure borne by the drum was 40 MPa. An experimental system of pulsed high-voltage discharge was designed based on the drum. A platform for discharging experiment was established according to the system principle diagram. The effects of variation in static pressure on discharging voltage, discharging current, critical breakdown field strength, discharging time and its data discretization, and other parameters were determined with water and crude oil as the discharging media. Experimental results indicate that increasing static pressure increases discharging time, enhances pulsed discharging randomness, reduces strength of impact waves generated in the discharging media, and weakens fracture-generating effect on the cement tube. Increasing the working voltage is necessary to achieve better plug removal. However, the requirements for size, texture, and insulativity of a plug removal equipment are correspondingly elevated. This study provides a basis for the application of pulsed high-voltage discharge technology in oil reservoir plug removal.