Method for analyzing tracer substances in multi-stage fracturing fluid flowback fluid to evaluate fracturing effect

Abstract

The invention provides a method for evaluating fracturing effects by analyzing tracers in a multi-section fracturing flow-back fluid. The method comprises the steps of sampling in an oil producing well and treating the sample, detecting the concentration of each tracer in the treated flow-back fracturing fluid, and evaluating the fracturing effect of each layer according to the concentrations of the tracers. The fracturing conditions judged by use of the method are visual and accurate, quantitative and low in error, and have an important guiding effect on the fracturing of the sections of the same layer; the design scheme is optimized for the conditions of different stratums; as a result, the fracturing efficiency is improved and the cost is reduced.

Description

technical field [0001] The invention relates to related technologies in the field of fracturing fluid flowback tracing, in particular to a method for analyzing tracer substances in multi-stage fracturing fluid flowback fluid to evaluate fracturing effects. Background technique [0002] At present, in the large-scale development of horizontal wells, multi-layer and multi-stage fracturing is the preferred process for formation stimulation, but the process of layer selection is not targeted. In the process of fracturing, especially in exploratory wells, layer selection is based on experience. Therefore, it is particularly important for data collection and analysis of fracturing effects after fracturing. [0003] In the existing technology, microseismic method, potential method, etc. can be used to monitor and analyze the development of fractures after fracturing, but there are disadvantages such as complex process and high cost, and often due to complex formation conditions an...

AI Technical Summary

Problems solved by technology

[0003] In the existing technology, microseismic method, potential method, etc. can be used to monitor and analyze the development of fractures after fracturing, but there are disadvantages such as complex process and high cost, and often due to complex formation conditions and many interference factors, it is difficult to analyze each layer. accurate explanation of the situation

In the previous staged fracturing of horizontal wells, only the amount of flowback fluid and whether there is oil or liquid can be known through the flowback fluid, but it is impossible to specifically judge the fracturing effect and fluid flow of each layer

[0004] Regarding the tracer technology of fracturing flowback fluid, there are still few relevant research reports at home and abroad. In the past, only chloride ions and mineral ions were used as reference targets. The detection accuracy is low and there are many interference factors. They are only used as auxiliary means for reference.

There is no previous report on the layered tracer of multi-stage fracturing.

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