RU2313557C2 - Multifunctional hydrophilic emulsion system for restoration of wells (options) - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: multifunctional hydrophilic emulsion system used during pullout of holes contains 0.5-5.0% phosphatide concentrate, structuring agent for hydrophilic emulsion rheology (carboxymethylcellulose), 0.1-0.2% antiseptic (chloroamine B), and water. In another embodiment of invention polyacrylamide is used as structuring agent instead of carboxymethylcellulose.

EFFECT: improved environmental safety accompanied with non-inflammability and low cost of emulsion system.

2 cl, 1 tbl, 8 ex

Description

The invention relates to the oil and gas industry, in particular to compositions used in the overhaul of wells.

A known composition for killing and completion of wells, containing, wt.%: Phosphatide concentrate 5.0-32.25; aqueous ammonia 0.5-1.0. (1) (Patent RU No. 2092516, class C09K 7/02, 1997).

A disadvantage of the known composition is the narrow scope of its application, the composition is used only for killing and completion of wells.

The closest in technical essence and the achieved result to the claimed multifunctional hydrophilic emulsion system for repairing wells is a hydrophobic emulsion composition for treating wells, containing, wt.%: Hydrocarbon fluid 12-16; wool fat acids treated with triethanolamine 0.3-0.5; calcium chloride 34-36; water the rest. (A.S. SU No. 1808859, class C09K 7/06, 1993).

The disadvantages of the known composition are the high cost due to the content of scarce raw materials lanolin and the need for special reagents - emulsion destructors due to its hydrophobicity, toxicity and combustibility of the composition due to the hydrocarbon content.

The objective of the present invention is to reduce the cost of creating an environmentally friendly and non-combustible hydrophilic composition.

The essence of the present invention lies in the fact that the multifunctional hydrophilic emulsion system for repairing wells, containing an emulsifier and water, according to the invention additionally contains a rheology structurator - carboxymethyl cellulose and antiseptic - chloramine B, while the emulsifier contains a phosphatide concentrate in the following ratios of components, wt. %:

phosphatide concentrate 0.5-5.0 carboxymethyl cellulose 1,5-5,0 chloramine B 0.1-0.2 water rest

The multifunctional hydrophilic emulsion system for repairing wells, containing an emulsifier and water, according to the invention additionally contains a rheology structurer - polyacrylamide and antiseptic - chloramine B, while the emulsifier contains a phosphatide concentrate in the following ratios of components, wt.%:

phosphatide concentrate 0.5-5.0 polyacrylamide 0.2-1.0 chloramine B 0.1-0.2 water rest

Phosphatide concentrate, carboxymethyl cellulose and polyacrylamide are non-toxic non-combustible substances that do not have a negative effect on human skin.

Chloramine B is an antiseptic widely used in production and in everyday life, it is produced according to TU 9392-031-00203306-97.

Phosphatide concentrate is an independent commercial product of oil and fat enterprises, manufactured in accordance with TU 9146-203-00334534-97.

Carboxymethyl cellulose is produced by the domestic industry according to TU 2231-002-5077563-2000.

Polyacrylamide is produced according to TU 6-0200-209912-41-94.

A multifunctional hydrophilic emulsion system for repairing wells is prepared as follows.

The estimated amount of phosphatide concentrate is mixed with 3/4 of the estimated volume of water by pumping. The calculated amount of chloramine B is dissolved in the second half of the calculated volume of water and the calculated amount of carboxymethyl cellulose (or polyacrylamide) is added and mixed by pumping.

The resulting compositions are mixed by repeatedly pumping to obtain a stable fine emulsion.

The proposed emulsion is prepared at the wellhead immediately before use or in stationary conditions. The stability of the emulsion from 15 days or more.

Example 1. 0.5 g of a phosphatide concentrate was placed in a flask, 50 ml of water was added and stirred for 10 minutes. 47.8 ml of water are poured into another flask, 0.2 g of chloramine B is added and stirred until it is completely dissolved, then 1.5 g of carboxymethyl cellulose is added and stirred for 30 minutes

The resulting compositions are poured into one flask and stirred for 5 minutes.

The viscosity of the obtained multifunctional hydrophilic emulsion system 35 sec, water loss 0.

Examples 2, 6, 8 are carried out according to example 1 with the only difference being that they take different ratios of components.

The compositions of the multifunctional hydrophilic emulsion system and quality indicators are shown in the table.

Examples 3, 4, 5, 7 are carried out according to example 1 with the only difference that instead of carboxymethyl cellulose, polyacrylamide is used and various ratios of components are taken.

The compositions of the multifunctional hydrophilic emulsion system and quality indicators are shown in the table.

Table Example No. The composition of the multifunctional hydrophilic emulsion system, wt.% Quality indicators Phosphatide Concentrate (FC) Carboxymethyl cellulose (CMC) Polyacrylamide (PAA) Chloramine B Water Conditional viscosity, sec Water loss, cm ^3/30 min one 0.5 1,5 - 0.2 97.8 35 0. 2 5,0 5,0 - 0.2 89.8 500 0 3 0.5 - 0.2 0.2 99.1 22 0 four 5,0 - 1,0 0.2 93.8 380 0 5 2.0 - 0.4 0.1 97.5 80 0 6 2,5 2,5 - 0.2 94.8 170 0 7 4.0 - 0.8 0.2 95.0 310 0 8 1.9 1.9 - 0.2 96.0 40 0

As can be seen from the table, the proposed ratio of the components is optimal.

The density of the emulsion may be less than one (up to 0.6 ÷ 0.7 g / cm ³ ), for which it is aerated with an inert gas or fuel combustion products, and also higher than one, for which aqueous solutions of salts (sodium or calcium chlorides) are used or weighting agents (barite, magbar, marble, hematite and others) are introduced into the emulsion.

The proposed multifunctional hydrophilic emulsion system is a universal process fluid. According to its physical and chemical properties, it is an unfiltered, non-clay working fluid, does not contain oil products, does not require the use of emulsion destructors, is inexpensive, is the basis of special-purpose process fluids for carrying out technological work on vertical and horizontal wells, wells with abnormally low formation pressures, wells of underground stations gas storages using traditional lifts and / or coiled tubing installations for the following tasks:

- killing wells;

- fastening the bottomhole formation zone;

- washing the face;

- hydraulic fracturing;

- opening of the reservoir.

The proposed multifunctional hydrophilic emulsion system for repairing wells is less expensive compared to the prototype composition. Its cost is 1-2 thousand rubles. for 1 t. The cost of the prototype composition is 8-10 thousand rubles. for 1 t

The multifunctional hydrophilic emulsion system is successfully used at gas production facilities and underground gas storage stations of Kubangazprom LLC.

Information sources

1. Patent RU No. 2092516, C09K 7/02, 1997

2. A.S. SU 1808859, C09K 7/06, 1993 - prototype.

Claims (2)

1. A multifunctional hydrophilic emulsion system for repairing wells containing an emulsifier and water, characterized in that it further comprises a rheology structure of the hydrophilic emulsion - carboxymethyl cellulose and antiseptic-chloramine B, while the emulsifier contains a phosphatide concentrate in the following proportions of components, wt.%% : phosphatide concentrate 0.5-5.0 carboxymethyl cellulose 1,5-5,0 chloramine B 0.1-0.2 water rest 2. A multifunctional hydrophilic emulsion system for repairing wells, containing an emulsifier and water, characterized in that it further comprises a rheology structure of the hydrophilic emulsion - polyacrylamide and antiseptic-chloramine B, while the emulsifier contains a phosphatide concentrate in the following ratios of components, wt.%% : phosphatide concentrate 0.5-5.0 polyacrylamide 0.2-1.0 chloramine B 0.1-0.2 water rest