HEAVY PROCESS FLUID FOR KILLING WELLS, COMPOSITION AND METHOD FOR PREPARATION THEREOF Russian patent published in 2020 - IPC C09K8/42 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to oil and gas industry, namely to completion and repair of oil and gas wells and can be used in conditions of abnormally high reservoir pressures and in conditions of low temperatures of Far North for killing and performance of various types of works. Heavy process fluid for wells killing is an aqueous solution obtained by dissolving in water at least: calcium nitrate in amount of 35 wt. % to 41 wt. %, calcium bromide as a weighting agent in an amount providing a density of liquid from 1.58 g/cm³ to 1.82 g/cm³ at 20 °C. Composition for preparation of heavy process fluid for killing wells, which includes dry calcium nitrate and calcium bromide in weight ratio from 1:1 to 1.4:1. Method of preparing heavy process fluid for killing wells, in which calcium nitrate is dissolved in water in amount of 35 to 41 wt. % of liquid weight, then in the resulting calcium nitrate calcium bromide solution was dissolved in an amount providing a density of liquid from 1.58 g/cm³ to 1.82 g/cm³ at 20 °C.

EFFECT: technical result is providing simultaneously low corrosion rate (up to 0_12 mm/year) and low freezing point (below minus 35 degrees Celsius) of heavy process fluid, which provides its use in a wide range of reservoir pressures.

20 cl, 2 tbl, 6 ex