Research On Matching Technology For The Deep Ultra-Heavy Oil In Es3 K119 Block

The Es3 formation in Gudao oil field is a deep,low porosity and low permeability ultra-heavy oil reservoir.The oil get an ultra-high viscosity,low seepage capacity,and sensitive reservoir,which cause the development of this block,is difficult.The paper aiming the problems carrying out the research and test formed a relatively effective exploitation matching technology.Through experimental analysis,indoor rheological analysis,reservoir damage mechanism of flow capacity evaluation,viscosity reduction optimization,testing and analyzing the oil flow characteristics of K119 block ultra-heavy oil,designing the adaptable reservoir transformation process,optimizing a deep ultra-heavy oil cold production technology by DC huff and puff and a method for deep ultra-heavy oil lifting technology.Those technologies have been applied in the oilfield.The results show that the key point of effectively developing K119 block is flow ability.Through the analysis of the components of crude oil from K119 block,analyzing the nature of high viscosity,find the regulation of stratum starting pressure through displacement experiments which the crude oil in various temperature or permeability,get a clear technology thinking about how to research,which is improving the permeability and reducing viscosity of crude oil.For the extremely strong water sensitivity of the reservoir,XFP anti swelling agent is preferably for reservoir protecting,also a better slug injection process is optimized.Optimizing the fracturing process,selecting the proppant,fluid and parameters,for the reservoir permeability transformation.Research the radial drilling technology for thin interbed formation,and put forward a compound organic retarded acid have 5 hours effective time.CO₂ and Dissolver have good viscosity reduction property for the Es3 of K119 block ultra-heavy oil,and the chemical cold production technology by CO₂ combined with Dissolver to reduce viscosity is adoptable in K119 block.Based on the compound study of CO₂ and Dissolver cold production system,a 7 slugs'injected combination with CO₂ as the dominant component was designed.Through the study of injection parameters optimization of chemical cold production,the injection parameters are determined according to the influence of various Dissolver and CO₂ strength on the production effect.For the analysis of the present application status of viscosity reduction technology,concluded the viscosity reduction technique of shaft electric heating is more adaptable in K119 block.The viscosity limit and temperature limit of oil lifting are determined by force analysis of wellbore lifting system and viscosity-temperature characteristics of the crude oil,furthermore,the minimum heating temperature and depth are also determined.A lifting technology process of K119 is designed through the analysis of the applicability of electric heating viscosity reduction and dilute viscosity drop lifting technology,it is electric heating+heat insulating tube+dilute adhesive.The heating depth was optimized by testing the liquid temperature with the variation of the well depth under different dilution ratio and different electric heating power.Totally,matching Technology of the deep ultra-heavy oil including reservoir protection and transformation,chemical compound cold production by huff and puff,viscosity reduction and wellbore lifting,are put in use at various 4 wells in K119 block,and high capacity in early time.