泥页岩水敏性评价新方法──比亲水量法研究

NEW METHOD FOR WATER SENSITIVITY EVALUATION OF SHALE──A STUDY ON SPECIFIC WATER WETTABILITY

基于近代表面物理化学有关理论和试验分析，首次提出并论述了比亲水量法是泥页岩水敏性评价的科学新方法。比亲水量法能克服传统总亲水量法的局限性，特别适用于当前面临的深井硬脆性泥页岩井壁稳定性的分析研究。文中概述并试验研究了比亲水量的测定方法。试验研究表明，ＥＧＭＥ法和亚甲基蓝法均是重复性好、准确可靠的泥页岩比表面测定方法，尤其是亚甲基蓝法简便易行，成本较低。比表面积和比亲水量是泥页岩水化变形和强度变化的决定性因素：试验测得了１０种泥页岩样的比表面积和比亲水量。

Based on the theory and lab analysis of modern surface physicochemistry,specific water wettability study is proposed for the first time and described as a new scientific method for water sensitivity evaluation of shale. It is suitable particularly for analysis of borehole wall stability hard and brittle shale in challenge of deep well drilling currently instead of the traditional bulk water wettability evaluation which exhibits some restriction. This paper presents the study and test in determination of specific water wettability. Study and test showed that both EGME and ethylene blue analysis are reliable and accurate for specific surface area determination with good repetition, particularly ethylene blue analysis is an easy and cheap method. Specific surface area and specific water wettability are decisive factors in strength change and hydrate deformation of shale. Data of specific surface area and specific water wettability for 10 shale samples were obtained in the test.