Method for evaluating shale hydration inhibition capability of water-based drilling fluid

Abstract

The invention provides a method for evaluating shale hydration inhibition capability of water-based drilling fluid, and belongs to the field of shale gas development. The method comprises the following steps: providing a dry shale sample, and testing the lattice interlayer spacing d001 of the dry shale sample; adding quantitative dried shale samples and to-be-evaluated water-based drilling fluid into a reaction flask, stirring at a set temperature, and carrying out centrifugal treatment; collecting hydrated precipitates of the shale sample, and testing the lattice interlayer spacing d001 of the hydrated precipitates; obtaining the difference value [delta]d001 and comparing the difference value with an evaluation standard, and judging the strength of the shale hydration inhibition capacity of the to-be-evaluated water-based drilling fluid; the evaluation standard being as follows: 0.22 > = [delta]d001 > 0, and the shale hydration inhibition capability being strong; 0.5 > = [delta]d001 > 0.22, and the shale hydration inhibition capacity being high; 0.7 > = [delta]d001 > 0.5, and the shale hydration inhibition capability being weak; 1 > = [delta]d001 > 0.7, and the shale hydration inhibition capability being weak.

Description

Technical field [0001] The present invention relates to the field of shale gas development, and more particularly to a water-based drilling fluid inhibiting the evaluation method of hydration capacity of mud. Background technique [0002] The mud shale is a rock formed by a stress and temperature of the clay, wherein there is a mix of stone, longite debris and other chemicals, and the mud shale is large, the pore is small, the structure is complicated, and it is easy to absorb water. When the water-based drilling fluid drill slut, the mud shale will hydrate in the water-based drilling fluid, which has caused the stability loss of the mud shale formation wall, and the cause of fragmentation and even even the wall collapsed. . To prevent the unstable wall of the drill mud rock formation caused collapse, water-based drilling fluid on mud flour peaks should have strong inhibitory capabilities. [0003] Currently, the laser particle size method is used to evaluate the inhibitory capac...

AI Technical Summary

Problems solved by technology

[0005] The test results of the laser particle size method are greatly affected by the stirring time and stirring rate, which can easily reduce the accuracy of the test results

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