Experimental Optimization of High-Temperature-Resistant and Low Oil—Water Ratio High-Density Oil-Based Drilling Fluid

Problems such as well loss and collapses in deep shale gas drilling are most often due to the development of cracks formation, resulting significant leaks fluid, sticking burrowing tools, other engineering accidents. In addition, horizontal sections wells very long issues friction, rock transport, formation contamination loom large. As a result, performance fluids directly affects efficiency, accident rates, reservoir protection effects. We first analyze mechanisms each emulsifier an oil-based fluid formulation filtration reduction mechanisms, taking into account collapse-prone abnormally high-pressure characteristics formations. undertake experimental evaluation optimization polymeric surfactants, primary secondary emulsions for high-performance fluids. The design rigid deformable nano-micron plugging materials with reasonable particle size range was achieved, we obtained low Oil—Water ratio high-density system, temperature resistance 200 °C, 70:30, compressive fracturing pollution 10%, maximum density 2.6 g/cm3. reuse rate reached 100%. developed system strong plugging, high density, suitable can effectively seal wall, reduce liquid invasion, prevent wall from collapsing, mud leakage, consumption improve utilization old mud, costs.