RU2458960C1 - Drilling mud - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: low-clay drilling fluid includes the following, wt %: clay 2.0-3.0, lubricating additive - residual product of wood advanced processing consisting of diterpenes 0.8-1.1, anti-foaming agent 0.2-0.3, water the rest.

EFFECT: improvement of lubricating and filtering parameters of drilling mud.

1 ex, 1 tbl

Description

The invention relates to the field of drilling oil and gas wells, in particular to water-based drilling fluids for drilling and pumping directional wells.

Known drilling fluid (Pat. RU No. 2369625, publ. 10.10.2009) containing a high molecular weight polymer reagent, low molecular weight polymer reagent, sodium hydroxide, sodium formate, xanthan biopolymer, bactericide, lubricant additive, water in the following ratio, wt. .%:

High molecular weight polymer reagent 0.07-0.2 Low molecular weight polymer reagent 0.2-0.5 Sodium hydroxide 0.02-0.05 Sodium formate 0.5-0.7 Biopolymer 0.1-0.2 Bactericide 0.02-0.1 Lubricant additive 0.2-0.5 Water rest

The disadvantages are the high cost of polymer additives and the multicomponent solution, which complicates the preparation process.

Known drilling fluid (Pat. RU No. 2268909, publ. 01/27/2006), including clay, carboxymethyl cellulose, an inhibitory additive, a lubricant additive and water, additionally contains a regulator of the structural and mechanical properties of carboxymethyl starch and an emulsifier - a mixture of esters and amides of fatty acids and ethanolamides, and as an inhibitory additive, the product of rectification of propylene oligomers of the isoolyphin type fraction C ₁₃ -C ₁₅ in the following ratio of components, wt.%:

clay 1.5-3.0 carboxymethyl cellulose 0.1-0.3 carboxymethyl starch 0.75-1.5 mixture of fatty esters and amides 0.75-1.0 acids and ethanolamides rectification product of oligomers isoolephin type propylene fractions C ₁₁ -C ₁₅ 0.75-1.5 lubricant additive 0.5-3.0 water rest

The disadvantage is the difficulty of regulating the structural and rheological properties of solutions.

Known drilling fluid (Pat. RU No. 20152588, publ. 15.05.1994), adopted as a prototype. The drilling fluid contains clay, water and a lubricant. As a lubricant additive contains a modified waste product for the production of fish oil from the stage of purification of industrial effluents with sodium ethylsiliconate or petrosil in the following ratio of components, wt.%:

Clay 8-10 Modified fish oil production waste from the stage of purification of industrial effluents sodium ethyl silicate or petrosil 1-2 Water Rest

The disadvantages are low lubricating properties, the need to modify waste plasticizer sodium ethylsiliconate, which has a cauterizing effect on the skin.

The technical result is the improvement of lubricating and filtration parameters of the drilling fluid.

The technical result is achieved in that the drilling fluid containing clay, a lubricant additive and water additionally contains an antifoam, and as a lubricant additive contains waste from deep processing of wood based on diterpenes in the following ratio of components, wt.%:

Clay 2.0-3.0 lubricant additive 0.8-1.1 antifoam 0.2-0.3 water rest

Clay is used as a builder and regulator of the thixotropic properties of the drilling fluid (increasing retention and transporting ability).

Adding antifoam is necessary to prevent foaming of the solution. Kerosene is used as an antifoam. Other defoamers can be used, for example, MAS-200 - highly dispersed hydrophobized organo-aerosil (silica), Penta-465 - multicomponent silicone antifoam, AM-5 - highly dispersed modified organo-aerosil (silicon dioxide), SOFEXIL-310 - hydrophobic Al silicone-liquid mixture, synthetic fatty alcohols, etc. (Ya.A. Ryazanov. Drilling mud encyclopedia, p. 256-261).

The use of wastes of deep processing of wood based on diterpenes as a lubricant additive can simultaneously reduce the friction coefficient and the fluid yield of the solution. Studies of the effect of waste on the properties of drilling fluids showed that an increase in their content in the mud of more than 1.1% does not lead to a significant improvement in technological parameters.

Used waste products based on diterpenes are taken at rosin-turpentine gum processing plants, where the main types of products are obtained: turpentine and rosin. These wastes are generated during the deep processing of wood to produce cellulose during sulphate cooking at the stage of sulphate soap processing and are diterpenes, mainly oxygen - the so-called "resin acids", which mainly include sandaracopimaric, isopimaric, abietic, neo-abietic, and other diterpenic acids.

The method of preparation of the drilling fluid

Example

A standard clay drilling mud is prepared in a mechanical stirrer, containing 95.7 wt.% Water and 3.0 wt.% Bentonite clay. Then, 0.3 wt.% Kerosene is introduced into the solution, the lubricant additive is 1.0 wt.% And mixed until a homogeneous mass.

After that, standard tests of the obtained solutions are carried out in laboratory facilities. To determine the lubricating and filtration parameters of drilling fluids, relevant studies were carried out, the results of which are shown in the table. The friction coefficient was determined at the metal-metal interface on the device USR1. A decrease in the coefficient of friction is observed even at minimum concentrations of the lubricant additive - at a concentration of 0.2 wt.%. The minimum values of the coefficient of friction are observed in the range from 0.8-1.1%, the coefficient of friction is reduced by 2.5-3 times. Thus, the lubricating and filtration parameters of the drilling fluid are improved.

The table shows that the use of drilling fluid reduces the torque during rotation of the drill pipe string and reduces the resistance forces during longitudinal movement of the string in inclined and horizontal sections of the wells, which reduces the likelihood of sticking and increases the life of the drilling equipment.

Claims (1)

A drilling fluid containing clay, a lubricating additive and water, characterized in that it additionally contains an antifoam, and as a lubricating additive contains waste from deep processing of wood based on diterpenes in the following ratio, wt.%:
Clay 2.0-3.0 Lubricant additive 0.8-1.1 Antifoam agent 0.2-0.3 Water Rest