Carbonatite oil well density selectivity water shutoff agent and preparation process thereof

Abstract

A density-selective water shutoff agent for carbonate rock oil wells, its component formula is by weight, 100 parts of cement, 60-75 parts of fly ash, 50-58 parts of clay, 52-62 parts of micro silicon, early strength 5-8 parts of agent, 16-28 parts of fluid loss reducer, and 1100-1200 parts of water. A preparation process of density-selective water shutoff agent for carbonate rock oil wells. The fluid loss reducer and early strength agent are weighed according to the above-mentioned formula quantity, dissolved in the water of the formula quantity, and then cement and fly ash are added into the formula quantity , Clay, and micro-silicon are fully dissolved to obtain the product. The beneficial effects of the density-selective water shutoff agent for carbonate rock oil wells provided by the present invention are: it is easy to stay between the oil-water interface, and a water shutoff partition is established; the curing effect is guaranteed; the injection is safe and the radius of water shutoff is expanded; High compressive strength; easy to prepare, good injectability, simple construction process and high construction efficiency.

Description

technical field [0001] The invention relates to an oil well water shutoff agent, in particular to components and a preparation process of the carbonate rock oil well water shutoff agent. Background technique [0002] Carbonate storage spaces are mainly karst fractures or caves, controlled by high-angle fracture zones and the development of karst pores and caves along the fractures, the reservoirs vary greatly in vertical and horizontal directions, and have strong heterogeneity. At the same time, there is a large bottom water body. During the production process, once the bottom water breaks through and enters the reservoir, the water cut of the oil well rises rapidly, resulting in a sharp drop in production. At present, the polymer jelly, conventional cement, and precipitation water shutoff agent used in the oil field water shutoff agent will degrade under the formation conditions of high carbonate temperature and high salt, and the solution viscosity is large. The pumping ...

AI Technical Summary

Problems solved by technology

During the production process, once the bottom water breaks through and enters the reservoir, the water cut of the oil well rises rapidly, resulting in a sharp drop in production

At present, the polymer jelly, conventional cement, and precipitation water shutoff agent used in the oil field water shutoff agent will degrade under the formation conditions of high carbonate temperature and high salt, and the solution viscosity is large. The pump injection resistance is large, which can easily block pipelines and other equipment; conventional cement is easy to leak and pollute the production layer, and the water blocking radius is small, and the effective water blocking range is small; the precipitation type water blocking agent has low strength and is not resistant to erosion

Therefore, the current conventional water plugging technology is not suitable for carbonate oil wells with high temperature and high salinity