Study On Water Plugging Technology By Emulsified Viscous Oil In Block Jin16

At present, exploration and development of block16in Jinzhou oil production planthas entered into middle and later period, during which many problems emerge,including seriously insufficient of high-quality reserves, scattered distribution ofremaining oil and difficult to tap, also, heavy oil reservoir block has entered intodevelopment stage of high and extra high water cut. Improving the developmenteffect by water plugging is a direct and effective mean at present. Water pluggingagent is mainly divided into two categories: the non selective water plugging agentand selective water plugging agent. Due to the non selectivity of non selective waterplugging agent, it is easy to cause damage for multi-layer development reservoir,seriously affecting the productivity of oil well, it also has problems of complexconstruction process, complex procedure and high cost. Therefore, selective pluggingagent become the main research object for scientific research personnel. Withinjecting active viscous oil into the ground, stable W/O emulsion forms once meetingwater at low agitation intensity and the increasing viscosity will prevent the formationwater flowing into well bottom; while, active viscous oil will be diluted if meeting oilof the formation, resulting in viscosity decreasing and oil flowing out of formation.Therefore, it is a kind of good selective plugging agent which plugs water and notplugs oil.Through a series of simulation experiments in the laboratory, the effects oftemperature, water ratio, salinity, the emulsifier concentration, the viscosity of crudeoil on the emulsion viscosity is studied, also long-term stability of emulsion. Thefollowing analysis of the experimental data makes the main factor affecting waterplugging by emulsified heavy oil clear. By the Indoor core simulation experiment, thispaper determines changes of pressure, recovery and breakthrough pressure and studiesinjection capacity of emulsified crude oil and sealing performance to ensurereasonable injection parameters. Studies have shown plugging agent with good sealedperformance that plugging rate reaches more than90%,breakthrough pressuregradient reaches more than5MPa/m and residual resistance coefficient reachesmore than10, can effectively plug formation. Three-tube parallel core water pluggingsimulation experiment shows that60%moisture content was the best waterplugging time.