Automatic restoration agent of well-cementing cement rings of rare-earth coordination type oil-gas well, as well as preparation and application of automatic restoration agent

Abstract

The invention discloses an automatic restoration agent of well-cementing cement rings of a rare-earth coordination type oil-gas well. The automatic restoration agent comprises the following components in parts by weight: 100-130 parts of active mineral and 2.0-8.0 parts of a rare-earth coordination type surface treatment agent, wherein the active mineral is mineral slag, pulverized fuel ash, cement or coal gangue; an inorganic powder multifunctional surface modification agent WOT102 or WOT108 is adopted as the rare-earth coordination type surface treatment agent. The invention also provides a method and an application of the automatic restoration agent of well-cementing cement rings of the rare-earth coordination type oil-gas well. According to the invention, the coating treatment is carried out on the surface of the active mineral by the rare-earth coordination type surface treatment agent and a waterproof protective layer is formed on the surfaces of the active mineral particles, so that the active material is converted from the dominant activity to potential activity; the automatic restoration agent can start hydration reaction when the cement rings are damaged, and formed hydration products can restore damaged parts, so that the automatic restoration of the well-cementing cement rings is realized and the significance for guaranteeing the service life and the mining safety of the oil-gas well is great.

Description

technical field [0001] The invention belongs to the technical field of petroleum drilling and cementing, and in particular relates to a rare earth coordination type oil and gas well cementing cement sheath self-repairing agent and its preparation and application. Background technique [0002] The cement sheath of oil and gas well cementing is a brittle material that is easy to shrink like the cement-based material on the building. In addition to the influence of various well tests, tests, production, production operations and formation conditions, the casing and cement sheath are affected. The impact of large changes in various factors such as temperature and pressure and the corrosion of various acidic fluids (such as carbon dioxide, hydrogen sulfide, etc.) in the well will inevitably produce micro-cracks inside the cement sheath. Micro-gap will be generated at the cemented interface, or the porosity of the cement sheath will increase, resulting in damage to the cement shea...

AI Technical Summary

Problems solved by technology

[0003] Once the cement sheath of oil and gas well cementing is damaged, its sealing performance will be damaged, forming a channel for channeling downhole formation fluid, resulting in the failure of interlayer isolation and the failure of casing protection function, causing oil layer casing damage, oil and gas A series of serious development problems such as rising water cut in wells, gas channeling in thermal recovery wells and chaotic distribution of underground oil, gas and water, damage to oil and gas layers, and leakage of underground natural gas and toxic gases

[0004] The basic method to solve the problem of oil and gas well cementing cement sheath damage is to use the costly cement-squeezing major workover repair method and chemical plugging repair method, but the success rate is low, and many damaged well repair operations need to be carried out 2-3 times, and some Accidents occur during the well construction process, and the repaired oil and gas wells often have problems in a short period of time and need to be repaired again