THERMAL RECOVERY STRING DESIGN AND WELLBORE THERMAL INSULATION ANALYSIS OF OFFSHORE HEAVY OIL WITH MULTI HEAT FLUID

摘要

According to the characteristics of multi-component thermal fluid and the safety requirements of offshore heavy oil recovery,we designed the injection horizontal section by sections,and formed the offshore multi-element thermal fluid injection string with high efficiency.Combined with wellbore thermal theoretical calculation,the thermal insulation technology of offshore heavy oil thermal recovery was optimized.The results show that the design of an increasing flange between the casing head and the tubing spool can prevent the casing from thermal elongation during heat injection.At the same time,the heat loss of injected fluid in the wellbore can be reduced,the heat utilization rate can be maximized,and the thermal recovery effect of offshore heavy oil can be effectively improved.