High temperature resistant anti-salt solid-free environment protection drilling and completing fluids

Abstract

The invention relates to a high temperature resistant salt-resistant no-solid-phase environment-friendly well completion drilling fluid, which can effectively overcome the shortcomings in the performance and the application of the prior well completion drilling fluid, in particular can avoid damage to stratum, and can meet the strict requirements for environment protection. The invention has the technical proposal that the well completion drilling fluid is made up from water, formate, viscosity increaser, filtration loss reducing agent, oil layer protective solute and polymeric-alcohol collapse preventing agent. The well completion drilling fluid is ensured to contain no solid-phase component, reduces the damage to the stratum greatly, has fine structural components, not only optimizes the overall performances of the system, but also improves the stability of heat resistance and salt resistance of the system. The constituents adopted by the invention are all water-soluble substances, the pollution on the environment caused by emissions is reduced, the system also can be recovered and recycled, and high-priced fluid preparing cost can be reduced greatly.

Description

1. Technical field [0001] The present invention mainly relates to oil drilling and completion working fluid with optimized performance, especially a high temperature resistant (200°C), salt resistant, solid-phase pollution-free and easy-to-degrade environment-friendly drilling and completion fluid with high temperature resistance, salt resistance and solid phase liquid. 2. Background technology [0002] In the current oil exploration and development process, due to their own characteristics, conventional water-based mud or oil-based mud often cause irreparable damage to the reservoir especially during the drilling process, so that the exploration and later development can draw wrong conclusions , which increases unnecessary and high treatment costs; at the same time, the commonly used barite weighting agent itself is insoluble and potentially harmful, which also leads to the high cost of waste drilling fluid discharge and treatment. Especially at high temperature, the solid...

AI Technical Summary

Problems solved by technology

At the same time, due to the complex chemical composition of some drilling fluid systems, the compatibility with cement is poor, which affects the subsequent cementing quality