Low Oil-Water Ratio Technology in Water-In-Oil Drilling Fluids for Cost Reduce of Unconventional Oil and Gas Drilling Fluids

In China’s unconventional oil drilling, horizontal wells are one of the main forms water-in-oil drilling fluid have been widely used due to their stable performance and excellent lubricating properties. To reduce high cost fluids at site, further pressure cuttings processing, meet requirements environmental protection, an oil-based system with a low oil-water ratio was developed. Based on research key emulsifiers introduction nanomaterials, it helps maintain while increasing water-phase ratio, enhances loss fluid. The developed has applied in section Jiaoye 5-3HF 21-S2HF, two Fuling shale gas block China, successfully drilled designed well depth. Marsh funnel viscosity is controlled from 63s 78s, plastic lower than 40 mPa·s, dynamic shear force maintained 3.5–7 pa, temperature water below 2.6 ml, demulsification voltage above 600v; properties Excellent, meeting on-site construction. Compared conventional system, can greatly content, which save large extent. It protection certain