The solid free compound brine drilling and completion fluid is a new generation of solid free drilling and completion fluid. Organic salt and inorganic salt are used to reduce liquid phase activity, polymer environmental protection materials are used to increase viscosity and reduce filtration loss, and nano plugging agent is used to strengthen plugging performance.

• Suitable density: over 1.7g/cm3 .
• Suitable cost: the cost is lower than that of potassium formate, and highly cost-effective.
• High inhibition: low water activity, inhibiting the hydration of clay components.
• Environmental protection and non-toxic: European and American countries permit direct discharge.
• Low corrosivity: compatible with metal materials and rubber seals, resistant to 6000ppm hydrogen sulfide.
• Wide scope of application: alternative oil-based drilling fluid, completion fluid and workover fluid, coiled tubing working fluid, etc.