Evaluation Of The Effect Of Steam Stimulation On The Karamay Formation In The 9-2 Area And Study On The Influencing Factors

The Karamay Formation Reservoir in Area 9-2 is a typical ordinary heavy oil reservoir.It has been developed by steam stimulation since it was put into production.After years of development,the oil production and oil-gas ratio of the reservoir have gradually decreased,the water cut has been rising,and the production effect has deteriorated.At present,the reservoir is in the middle and late stages of steam stimulation development,and the recovery degree is only 28%,which is far from meeting the recovery requirements of the steam stimulation method.The main reason for affecting the development effect is to propose reasonable measures and suggestions for the existing problems,so as to slow down the intensification of production contradictions,improve the recovery degree of the reservoir,and give the old area a new look.This thesis mainly starts with the evaluation of the development effect of steam stimulation and the research on the influencing factors.Using a combination of theoretical research and practical application,the development effect of the steam stimulation stage is systematically evaluated and the influencing factors are analyzed.,And put forward the next step of comprehensive adjustment measures,combined with numerical simulation methods to select the best plan,which provides an important theoretical basis for the later development of the reservoir.In order to ensure the rationality and effectiveness of the evaluation of the development effect,seven evaluation indicators for the development effect of the reservoir were selected: oil recovery rate,cumulative oil-vapor ratio,comprehensive decline rate,comprehensive production rate,recovery water rate,comprehensive water cut rate,and throughput cycle,Established an evaluation index system,and evaluated the development effect from 7 indexes.At the same time,fully combine the mathematical analysis method to evaluate the reservoir development effect.The order of strength of the evaluation indicators is determined by the gray correlation method.The analytic hierarchy process is used to quantify the qualitative evaluation indicators,and the weights of the indicators are calculated.The fuzzy comprehensive evaluation model of the reservoir is established using fuzzy comprehensive evaluation theory.The actual production materials,and finally comprehensive evaluation of the reservoir steam stimulation production effect is "good",the comprehensive score is 0.435.On the basis of comprehensive evaluation of reservoir development effects,single-well classification was carried out using cluster analysis method,single-well evaluation was carried out,and the production and plane distribution laws of different wells were implemented.A comparative analysis of the influencing factors was carried out from the two aspects of geology and technology.The main control factors affecting the development effect of each well area were crude oil viscosity,oil layer thickness and oil saturation.Based on the evaluation of development effects and the comprehensive analysis of influencing factors,the next step of comprehensive adjustment measures was proposed for different well areas,and it was determined that the first type of well area continued conventional steam stimulation,the second type of well area used group steam stimulation,and the third type The well area is mined with one injection and multiple mining methods.A numerical simulation model of the well area was established,and the injection and production parameters of the selected scheme were optimized through numerical simulation,and the optimal scheme under different production methods was determined,which provided theoretical basis and technical support for the later development of the reservoir.