SU1002342A1 - Hydrophobic emulsion drilling mud - Google Patents

Description

(54) HYDROPHOBIC EMULSION DRILLING SOLUTION

The invention relates to the field of drilling oil and gas wells, in particular, to drilling fluids used when drilling wells in difficult geological conditions, as well as when opening productive horizons.

Known invert emulsion drilling fluid containing,%: water with varying degrees of mineralization 60-90, oil 5-35; an emulsifier from the class of esters of unsaturated higher acids and polyhydric alcohols, for example, emultal, 0.5-2.5, and oxidized petrolatum, 2-5 1.

The main disadvantage of this solution is that when it is contaminated with hydrophilic rock, such as clay, in an amount in excess of 20-25%, a sharp increase in the aggregative stability of the system occurs. This process is intensified at elevated bottomhole temperatures (70 ° C).

Also known is a hydrophobic emulsion drilling fluid consisting of diesel fuel, a saturated solution of sodium chloride, an emulsifier — SMAD-1, a builder of hydrated lime, and a hydrophobicizer of the cationic surfactant — penazopine 2.

The disadvantage of this solution is also low agriggative resistance when contaminated with hydrophilic rocks in an amount of 40 wt.% (By volume of the solution).

The aim of the invention is to increase the aggregative stability of a hydrophobic emulsion drilling mud when contaminated with hydrophilic rocks.

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The goal is achieved by the fact that in a hydrophobic drilling fluid containing diesel fuel, an emulsifier - SMAD-1, saline water, a structurant, and a water repellent agent, as a structurant

15 caustic soda is used, and as a water-repellent agent - non-ionic surfactant - polyoxyethylene alkylphenol (OD 7 or OD 10) with the following ratio of ingredients, wt.%:

20

Diesel 30-50

SMAD-18 12

Polyoxyethylated

Alkylphenol035-0.7 Caustic soda (or) 0.15-03 Mineralized water Remaining Completely acidified; alkyl phenols and are large-scale products of the petrochemical industry, their number indicates the number of molecules of ethylene oxide groups. An example of the preparation of a hydrophobic emulsion drilling mud. 50 cm of the SMAD-1 reagent is dissolved in 200 cm of diesel fuel and, with stirring, using a paddle stirrer with an intensity of 3.1 thousand revolutions of the shaft per minute, 250 cm of mineralized 6 "x are gradually poured. Stirring is performed for 10 hours until stabilization in time of the electrical stability indicator. Then, 333 g of OP-7 or OP-10 and 1.67 g of caustic soda are added and the emulsion is additionally mixed for 0.5 hours. The aggregative stability of the hydrophobic emulsion drilling mud when contaminated with efo by hydrophilic rocks is estimated by the maximum amount of bentonite clay (maximum alumina capacity) KOT swarm can be introduced into the system with the maximum content of the aqueous phase, without causing phase reversal, (the indicator of electrical stability at phase reversal is 0). These laboratory studies of the maximum clay content of the prototype and the proposed solution are given in table. 1. As can be seen from the table. 1, the maximum alumina capacity of the prototype is 40%, the content of 1,224 of the aqueous phase of the emulsion is 50 Increasing the content of penazoline Ver; it was not possible to increase the alumina of the hydrophobic emulsion solution containing 50 or more wt.% Of the aqueous phase from 0.2 wt.%. From tab. 2 that the maximum clay content of the proposed solution with a content of the aqueous phase in the range of 50-60% is equal to 47%. Thus, the proposed hydrophobic emulsion drilling mud differs from the prototype in a higher aggregative resistance when contaminated with its hydrophilic rock. The increase in the consumption of OP-7 (OP-10) in excess of 0.7%, and caustic soda in excess of 0.3% does not lead to a further increase in the aggregative stability of the emulsion. Reducing the consumption of OP-7 (OP-10) to; the level is less than 0.35%, and caustic soda is less than 0.15%, the positive effect from the introduction of polyoxylated alkylphenols and caustic soda is practically absent. The high clay content of the present system (up to 47%) will reduce; the cost of funds and thunder to maintain the required quality of it in the process of drilling. This will also reduce the severity of drilling complications and improve the quality of opening the productive horizon. The expected economic effect from the use of a hydrophobic emulsion drilling mud when drilling under complicated conditions is approximately within 5-7 rubles. on 1 m of drilling.

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Claims (2)

Polyoxyethylated Claim Hydrophobic Emulsion Drilling Ras-IliOP-10) 035-070 creator containing diesel fuel, emulsifier-Caustic sodaO.lS-O O torus - SMAD-1. mineralized water., Mineralized water Else a structural agent and a water repellent agent, characterized in that, in order to increasing its aggregative stability Sources of information when contaminated with hydrophilic rocks, taken into account during the examination fg is used as structurant caustic srda, and as hydrophobic-1- USSR Copyright Certificate No. 570626, mash - non-phenolic surfactant - polyoxystil-cl. From 09 to 7/06, 1971. alkylphenol (OP-7 or OP-10) 2. Rozengaft A.G. and others. Experience with in the following ratio of ingredients, hydrophobic emulsion drilling mud.%: 15 treated with cationic surfactants. Diesel fuel30-50Seri Drilling. M., VNIIOENG, № 10, , SMAD-18-121978, p. 28-30 (prototype). alkylphenol (OP-7