High temperature-resistant and solid-free micro-foam drilling fluid or completion fluid

Abstract

The invention discloses a high temperature-resistant and solid-free micro-foam drilling fluid or completion fluid. The drilling fluid is prepared from the following raw materials by weight: (1) 0.5-1 part of a high temperature-resistant tackifier; (2) 0.5-1 part of a high temperature-resistant foaming agent; (3) 0.2-0.3 part of a high temperature-resistant protective agent; (4) 2-3 parts of a high temperature-resistant fluid loss additive; (5) 0.6-1 part of a high temperature-resistant flow type conditioning agent; (6) 0.2-0.3 part of soda ash; and (7) 100 parts of water. The preparation method includes: adding the above (1)-(6) components into the component (7) according to the content sequentially under the conditions of normal pressure and temperature and mechanical stirring in a usual way, and then conducting stirring for 2-6h. The drilling fluid or completion fluid provided by the invention has the advantages of excellent rheological properties, good fluid loss reducing performance, good stability and high temperature resistant ability, and can be applied to well drilling or completion construction in high temperature, low pressure and likely leaking stratums.

Description

technical field [0001] The invention relates to a drilling fluid and a well completion fluid, in particular to a high temperature resistant solid-phase microfoam drilling fluid or a well completion fluid. Background technique [0002] With the increasing consumption of oil and gas resources and the development of extraction technology, the exploration and development of oil and gas in the ocean has become a new focus. Most of my country's offshore oil resources belong to clastic rocks and ancient buried hill carbonates. The formation lithology is limestone weathering crust with good connectivity and high porosity. It belongs to low-pressure, high-porosity and high-permeability formations. Conventional drilling This technology will lead to a large amount of drilling fluid leakage, seriously pollute the oil and gas layers and even cause the well to be scrapped. The micro-foam drilling fluid system has the advantages of low density, strong rock-carrying ability, strong inhibiti...

AI Technical Summary

Problems solved by technology

The disadvantages of the above technology are: 1. The system contains a relatively large amount of bentonite, which needs to be pre-hydrated and mixed, the process is complicated, and the waiting time is long; 2. The existence of a large amount of bentonite will lead to poor uniformity and stability of the foam; 3. , Submicron solid particles such as clay contained in the system will cause damage to the reservoir, making it difficult to protect and discover oil and gas layers to the maximum extent

However, the temperature resistance of the solid-free microfoam drilling fluid system is not high, only 100°C, which limits the application of this system in high-temperature formations

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