Method and device for determining imbibition band width after fracturing imbibition in horizontal well

Abstract

The invention discloses a method and a device for determining the imbibition bandwidth of a horizontal well after fracturing imbibition. The method comprises the following steps of: acquiring effective data characterizing innate geological characteristics and acquired development characteristics of a reservoir; using the seepage models of the main fracture area, the seepage imbibition area, the fracture network reformation area and the low seepage area established in advance and the limited conditions thereof, predicting the pressure data corresponding to the position and the production timewhen the seepage imbibition bandwidth takes different values in the fixed production of horizontal wells; predicting Laplace space yield prediction data during production of fixed well bottom pressureof a horizontal well;; forecasting time-based yield data in actual space; selecting the value of the infiltration bandwidth corresponding to the yield data with the highest fitting degree of the actual yield is selected as the final infiltration bandwidth. The scheme greatly reduces the calculation error caused by reservoir heterogeneity, and the final horizontal well imbibition bandwidth after fracturing has higher rationality, which can more accurately determine the impact range of fracturing fluid after injected into the formation, and provide a basis for reservoir production.

Description

technical field [0001] The invention relates to the technical field of hydraulic fracturing, in particular to a method and a device for determining the imbibition bandwidth after fracturing imbibition in a horizontal well. Background technique [0002] With the increasingly tense relationship between the supply and demand of oil and gas resources in the world, the development of tight reservoirs has received more and more attention. The main technologies for its successful development are long horizontal sections and large-scale hydraulic fracturing. Field statistics show that the flowback rate of injected fracturing fluid during hydraulic fracturing is often only 10-50%, and a large amount of fracturing fluid stays in the formation. [0003] For example, the pressure coefficient of a certain reservoir in Changqing Oilfield is low, the flowback rate of fracturing fluid after hydraulic fracturing operation is low, and the flowback time is long, and the output remains stable d...

AI Technical Summary

Problems solved by technology

Although a mathematical model that can be applied to fractured reservoirs has been established, this model uses capillary force to characterize imbibition, and it is better for reservoirs with little difference in physical property parameters. In this case, the method is unreasonable; some studies have considered the influence of the boundary layer, but have not described the flow differences in different regions of the fractured horizontal well; some studies have established shale gas Numerical simulation model for fracturing horizontal wells, which describes the retention and imbibition of fracturing fluid by modifying the porosity and permeability in the fractured area of ​​single-porous media. The characterization of imbibition mechanism is not clear

Moreover, at present, the determination of imbibition bandwidth is usually estimated by injection rate and reservoir thickness, without comprehensive consideration of imbibition and complex fracture network of fracturing, the method is simple and the accuracy is low

[0005] Therefore, the imbibition modeling and the determination of the imbibition bandwidth for fracturing fractures and complex fracture networks still need further research.

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