Research On Effective Production System Evaluation And Comprehensive Adjustment Measures Of Shu322 Block With Ultra-low Permeability

This paper takes the three types of blocks in the low-permeability Fuyang oil layer in Yushulin Oilfield-Shu322 block as the research object,establishes an effective production system evaluation method,and evaluates whether oil and water wells can establish an effective production system according to injection-production well groups.The oil and water wells with an effective production system have optimized a reasonable work system,and measures to tap the potential of the oil and water wells that have not established an effective production system have been given.Based on the non-Darcy seepage theory basis,combined with the characteristics of the Yushulin Oilfield well pattern,an effective production coefficient calculation model considering the starting pressure gradient was established in this study.The control sand body area of each small layer of oil and water wells was counted layer by layer,and the effective thickness was adopted.The weighting method calculates the effective production coefficient of oil and water wells and well groups.Through regression analysis of calculation results and production parameters such as oil and water well fluid production intensity,water injection intensity,etc.,the effective production evaluation criteria are divided,and the oil and water wells and well groups that can and cannot establish an effective production system are identified.Secondly,using modeling software,a geological model of the Shu322 block and a dual-porosity and dual-permeability numerical simulation model considering the starting pressure gradient were established,and the main development indicators were historically matched,and a good fitting effect was obtained.For the well group that can establish an effective production system,according to the productivity equation and the pump condition of the pumping unit,a reasonable bottom hole flow pressure of the oil well is determined to be about 3MPa;the reasonable injection-production ratio is determined by establishing the calculation relationship between the injection-production ratio and the formation pressure It should be kept between 2.5 and 2.75;the reasonable water injection intensity of the well is determined to be 0.94t/(d·m).For well groups that fail to establish an effective production system,reservoir engineering methods and numerical simulation methods are used to predict the effect of reservoir reconstruction,and the corresponding technical parameters for fracturing of oil wells with different permeability levels and acidification of water wells with different pollution levels are optimized.After determining the comprehensive adjustment plan,numerical simulation methods were used to predict the development indicators for the next ten years.The final recovery rate of the block reached 23.85%,an increase of 0.87 percentage points,and the recoverable reserves increased by 6.81×10~4t.At the same time,through the evaluation of economic benefits,the implementation of the corresponding program also has considerable economic benefits.