Treatment method of bottom-hole oil formation zone. RU patent 2501943.

FIELD: oil and gas industry.

SUBSTANCE: in treatment method of bottom-hole zone of an oil formation, which involves series pumping of hydrocarbon solution of the product based on non-ionogenic surface active substance and acid-containing reagent, as hydrocarbon solution of the product based on non-ionogenic surface active substance there used is hydrocarbon solution of emulsifier of inverted emulsion of hydrocarbon solution of a mixture of non-ionogenic surface active substances, or hydrocarbon solution of a mixture of non-ionogenic surface active substances with anionic surface active substances, which is forced through with water to the formation; exposure is performed during 1-24 hours; after that, acid-containing reagent is pumped and forced-through with water to the formation.

EFFECT: improving treatment efficiency.

4 ex, 2 tbl

Field : oil producing industry, particularly, to methods of processing of bottom-hole zone of a petroleum layer, and can be used to enhance oil recovery.

A method of processing of inhomogeneous of a petroleum layer, including sequential injection into the reservoir hydrocarbon solution of surface-active substance (SAS) and acid composition (RF Patent№2119048, E21B 43/27, publ. 1998). In quality of PEAHENS use with the degree of sorbitan 3-5 (Neonol 9-4 or 9-5) and/or polyethylene glycol ether-based primary fatty alcohols ( ALM-3). As the acid composition of use composition DN-9010-an aqueous solution of hydrochloric acid sulphite liquor, surfactants and solvents, or SNPH-9010-an aqueous solution of solvents, surfactants and hydrochloric acid, or an aqueous solution of hydrochloric and hydrofluoric acids, solvents, surfactants and inorganic salts or hydrochloric acid or a mixture of hydrochloric and hydrofluoric acids. This method is not efficient enough, because blocking properties of the emulsion formed in the reservoir with the interaction used by the patent hydrocarbon surfactant solution with waters, well, not high enough. In addition, surfactants used on the basis of primary fatty alcohols are expensive and scarce food and acid composition (SNPH-9010 or DN-9010) differs and high cost.

There is a method of acid treatment of a petroleum layer, including the injection of hydrophobic emulsion and acid solution (Ed. SVID. The USSR №898047, MKI E21B 43/22, 1982). Hydrophobic emulsion contains oil, produced water or hydrochloric acid and emulsifier ES-2 or -2. As the acid solution using 10% hydrochloric acid. Disadvantages of this method are: the need to use special mixing devices for the preparation of hydrophobic emulsion, which complicates and increases the cost of the technology of processing of the oil reservoir; insufficient clogging saturated intervals emulsion; low technological efficiency.

Closest to the technical nature and the result achieved by the proposed technical solution is a method of treatment of the bottomhole zone of a petroleum layer, including sequential injection blocking agent - oil with oil treatment units, hydrocarbon surfactants in a mixture with mineralized water or aqueous solution of polyacrylamide, and acid composition containing nonionic surfactants, hydrochloric acid or a mixture of hydrochloric and hydrofluoric acids, water, faction and technical lignosulfonate (RF patent №2291959, IPC E21B 43/22, C09K 8/60, 2007). The known method is not efficient enough because of low blocking properties of used compositions, is difficult on the implementation due to the high viscosity of the injected blocking compounds, due to their insufficient low temperatures pour point (freezing) and is not suitable for wells with high water extracted products (above 50-60%). In addition, used in method acid composition is multi-component and expensive, complicated the implementation of the method.

The present invention is a high-tech and efficient way of processing of bottom-hole zone of a petroleum layer, which allows for the long-quality lock water-saturated oil wells, providing the penetration of injected in the subsequent reagent in low-permeability interlayer's not covered earlier influence.

The problem is solved so that the method of treatment of the bottomhole zone of a petroleum layer, which includes the sequential injection solution of surface-active substances and reagent, as solution of surface-active substances are used hydrocarbon solution surfactant (NS), or hydrocarbon mixed solution of nonionic surface-active substances, or hydrocarbon mixed solution of nonionic surfactants from surfactants (AS), who is forced into the reservoir water, hold the shutter speed 1-24 hours, after which pumped reagent is forced it into the reservoir water.

As nonionic can be used, for example:

- ethoxylated on the basis of trimers propylene with the degree of sorbitan 4, 6, 8, 9, 10, 12 on the other 2483-077-05766801-98;

OP-10-product processing mono - and oxide ethylene GOST 8433-81;

- neonols α-12, or α 14 - ethoxylated based on alpha-olefins TU 38.507-63-0302-93;

- Emulsifier e-1, which is a solution of nonionic surfactants in a hydrocarbon solvent, on the other 2458-012-22657427-2000 with MEAs. 1;

- Emulsifier e-2, which is a solution of nonionic, synthesized in the form of amido-amine salts of higher fatty acids C12-C18 and hydrocarbon CME- solvents, on the other 2458-001-22650721-2009;

- Emulsifier AMY, representing an emulsifier invert emulsions, on the other 2484-007-57412574-01;

- Emulsifier EM, representing an emulsifier invert emulsions in a hydrocarbon solvent, on the other 2413-048-48482528-98;

- Emulsifier the GSZ, which is a hydrocarbon dispersion esters of oleic, linoleic, linolenic, and resin acids, and colloid-dispersed phase, on the other 2458-057-17197708-01;

- other, or their mixture.

As ASAS is used by oil or synthetic sulfonates. Petroleum sulfonates (NS) with the equivalent mass of 400-580 are sodium, calcium or barium salts sulphonic acids of oil fractions, namely:

- sulfonates, which are the basis of additives, for example, S-150, s-300 TU 38.101685-84 or emulsifiers, for example, -2 according to the TU 38.101545-75, NGL-205;

- sulfonates sodium oil TU 38.50729-88;

- oil sulfonate brand «HL» company Vitko (USA) and others.

As synthetic sulphonates (SS) use , mono - and with the equivalent mass of 300 to 390 TU 6-01-1612839-34-90, TU 2481-037-04689375-95.

As a hydrocarbon solvent use:

- absorbent TU 38.103349-85 is a mixture of liquefied aliphatic and aromatic hydrocarbons obtained in the production of monomers for synthetic rubber;

- absorbent N TU 2411-036-05766801-95 - a mixture of paraffin and olefin hydrocarbons, heavy hydrocarbons and resins, represents a mixture of by-products production of monomers for synthetic rubber;

- distillation distillation residue of ethylbenzene and styrene () TU 2414-033-05766801-95 - a mixture of alkyl benzenes is a byproduct of the distillation of ethylbenzene and styrene;

- the liquid fraction tire pyrolysis () TU 2451-004-0136353-2003 - a mixture of aliphatic and aromatic hydrocarbons;

- liquid products of pyrolysis () faction 35-230°C and 35-270 OC along TU 38.402-62-144-93 - a mixture of unsaturated, naphthene, aromatic hydrocarbons;

- liquid products of pyrolysis (), tar oil type E for export beyond 38.402-62-130-92 - a mixture of unsaturated and aromatic hydrocarbons with admixture waxes and naphthenes, obtained by the pyrolysis and other high-temperature processes, oil and ;

- faction of aromatic hydrocarbons - faction (TF) TU 38.103579-85;

- nefras Ar 120/200 TU 38.101809-90 - a mixture of aromatic hydrocarbons;

- diesel fuel (DT) in accordance with GOST 305-82 - product fractional oil processing;

- the waste diesel fuel (OTD) TU 6-00-0203335-41-89;

- (SM) TU 30-0147585-018-93 - product of the fraction of high sulfur oil refining;

- faction (FG) TU 2411-032-0576680-95;

- faction of the broad lung gas liquids (NGL) TU 38.101524-93;

- the waste diesel fuel (OTD) TU 6-00-0203335-41-89 - waste production of ethylene;

- solvent paraffin oil (RPN) TU 0251-06200151638-2006;

- oil (GOST 9965-76) and others, as well as their mixtures.

As reagent (CR) can be used, for example, hydrochloric acid on the other 38-103141-78, or inhibited hydrochloric acid on the other 2122-131-05807960-97, or a mixture of inhibited hydrochloric and hydrofluoric acids () TU 6-01-14-78-91, or composition (CCM) brand HCL ML or HCL IO TU 2458-170-83459339-2008), or clay-acid composition of GK mark ML and CC IO (TU 2458-171 and others).

Hydrocarbon solution of PEAHENS are preparing the mix of components to obtain a homogeneous solution in the factory or directly on site. Hydrocarbon surfactant solution is stable at temperatures from -50 C to +30 C for a long time, has a low pour point of minus 60 C to minus 45 degrees.

Component composition of the hydrocarbon-surfactant solutions (UR SAS), the proposed method and physico-chemical properties of emulsions formed when mixed with water - stability, viscosity are shown in table 1 (samples trains №1-10). Here are the physico-chemical properties of the prototype (samples no 11a, b, C). As seen from table 1, surfactant in a hydrocarbon solvent on the proposed method are technological, have low viscosity, and emulsions mixing with water have high viscosity and are stable, unlike the original.

Evaluation of the effectiveness of the proposed and known ways to spend in laboratory conditions change in the permeability of seams and on the increase in the displacement factor (table 2). Studies carried out on models of heterogeneous on the permeability of the reservoir with two hydrodynamically not related areas of high - and low-permeable interlayers. The latter consist of a tube length of 0.5 m and a diameter of 0,032 m filled with crushed carbonate or terrigenous Kern and attached to one pressure container. First through model pumped produced water, then the model is saturated with oil, which displace water to achieve 98-100% water content by . Residual oil saturation model of low permeability is within 43-60%. Next, enter hydrocarbon surfactant solution then pumped water. Then hold the shutter speed 1-24 hours, after which pumped reagent and cut through the water.

Table 2 shows the data will be changed permeability layers and displacement factor increases after processing models on the declared and the known methods.

Give examples of specific implementation method.

Example 1.

To 5.4 surfactants brand With-150 type 8.7 g 9-6, then added with stirring 85,9 g of the mixture of absorbent and adsorbent N (taken in a volumetric ratio 1:2).

In the model flooding of the oil reservoir pump (composition №1 of table 1) in the amount of 20% of the volume of pores, then pump water in the amount of 40% of the volume of pores, followed by exposure for 1 hour. Then pumped 15% hydrochloric acid in the amount of 5% of the pore volume, and then push him water.

Examples of 2-3 perform similarly to example 1, by changing the number, type of reagents and the time of exposure.

Example 4 - (prototype) - sample # 11a from the table 1.

The results of testing the proposed method and the known (prototype) are presented in table 2.

Analysis of the data of table 2 shows that the proposed method is more effective in comparison with the prototype, as evidenced by higher values of permeability changes and growth displacement factor.

The proposed method is a high-tech, since it is based on the use of hydrocarbon-surfactant solution with low pour point and viscosity. The method allows to obtain stable emulsion with high viscosity, providing the highest quality lock flooded areas of oil wells. As these emulsions are formed at interaction of compositions of surfactants from water directly in the reservoir, do not want to apply special additional equipment for producing emulsions, unlike the original, that provides lower.

Thus, the proposed method allows to carry out long-term high-quality lock water-saturated layers of oil wells and penetration injected in the subsequent reagent in low-permeability interlayer's not covered earlier influence.

Way of processing of bottom-hole zone of a petroleum layer, including sequential injection of hydrocarbon product solution on the basis of nonionic surfactant and reagent, characterized in that in the capacity of hydrocarbon product solution on the basis of nonionic surface-active substance use hydrocarbon solution emulgatora emulsion, or hydrocarbon mixed solution of nonionic surface-active substances, or hydrocarbon mixed solution of nonionic surfactants from surfactants, which is forced into the reservoir water, hold the shutter speed within 1-24 hours, then pumped reagent is forced it into the reservoir water.