Method and composition for tertiary method of hydrocarbons production

FIELD: oil and gas industry.

SUBSTANCE: invention mainly relates to methods of hydrocarbons production from hydrocarbons containing reservoirs. Method of treatment of the reservoir containing crude oil including stages when: (a) composition is supplied to extract the hydrocarbons to at least part of the reservoir, at that the composition contains at least two internal olefin sulphonates selected from group comprising internal C15-18-olefin sulphonates, internal C19-23-olefin sulphonates, internal C20-24-olefin sulphonates and internal C24-28-olefin sulphonates, and at least one viscosity decreasing compound, that is isobutyl alcohol, ethoxylated C2-C12-alhohol, 2-butoxyethyl, butyl ether of diethylene glycol or their mixture, and (b) composition is provided with possibility to react with the reservoir hydrocarbons. Invention also relates to method of viscosity decreasing of composition of highly active surface-active substance and composition for hydrocarbons extraction.

EFFECT: result is creation of more effective method of hydrocarbons extraction from crude oil containing reservoir.

14 cl, 2 dwg, 2 tbl, 2 ex

 

The technical field to which the invention relates

The present invention mainly relates to methods for the production of hydrocarbons from hydrocarbon-bearing formations. More specifically, the described variants of execution are ways tertiary method of production of hydrocarbons and to compositions applicable for this production, which contain internal reincorporate and connections to reduce the viscosity.

The level of technology

Hydrocarbons can be extracted from hydrocarbon-containing formations by proburivaya of the layer of one or more wells. The hydrocarbons can flow to the surface through boreholes. Conditions (e.g., permeability, hydrocarbon concentration, porosity, temperature, pressure, among other things) a hydrocarbon reservoir can affect the economic feasibility of extraction of hydrocarbons from hydrocarbon-containing formation. The hydrocarbon layer may have a natural energy (e.g., gas, water), to promote the hydrocarbons to the surface from hydrocarbon-containing formation. Natural energy can be in the form of water. Water can exert pressure to promote hydrocarbons to one or more productive wells. Gas may be present in the hydrocarbon reservoir (reservoir formation) at pressures �to promote residual hydrocarbons to one or more productive wells. The source of natural energy over time may be depleted. To continue the extraction of hydrocarbons from hydrocarbon-containing reservoir may be subject to additional methods of extraction. Examples of additional techniques include flooding, injection of polymers, Plenum alkali, thermal processes, water flooding solutions or combinations thereof.

In the tertiary method of oil recovery (EOR) mobilization of residual oil saturation is achieved by using surfactants that create enough (ultra)low interfacial tension (IFT) at the interface oil/water to provide the capillary number is high enough to overcome capillary forces and motivations of oil to an article by authors I. Chatzis and N. R. Morrows, "Correlation of capillary number relationship for sandstone" ("Correlation of capillary number for Sandstone"), SPE Journal, volume 29, pp. 555-562, 1989).

Known compositions and methods of the tertiary method of oil recovery using surfactant component comprising an alpha reinsulate. U.S. patent 4488976 and 4537253 describe compositions for tertiary method of oil production, containing such a component.Known compositions and methods of the tertiary method of oil recovery using internal reincorporation. Such surface-active composition is described in patent� USA 4597879.

U.S. patent 4979564 describes the application of internal reincorporated in the way tertiary method of oil recovery using water flooding viscous liquid with low surface tension. One example of a commercially available on the market material, described as applicable, was ENORDET IOS 1720, the product company Shell Oil Company identified as sodium salt of sulfonated internal C17-20-olefin. This material has a low degree of branching. U.S. patent 506804 3 describes a surfactant system containing soap oil acids, for flooding, which used auxiliary surfactant comprising inner C17-20or C20-24-reincorporate. In "Field Test of Cosurfactant-enhanced Alkaline Flooding" ("Field tests injection of alkali to the intensification of the auxiliary surface-active substance") of the authors Falls, etc., Society of Petroleum Engineers Reservoir Engineering, 1994, the authors describe the use of internal C17-20or C20-24-reincorporate in the composition for water-flooding with surface-active substance on the basis of alkoxysilanes alcohol to maintain the composition in a single phase state at ambient temperatures without significant damage to the technical characteristics at the temperature of the reservoir tank. Water had salinity with containing�education of sodium chloride to about 0.4% by weight. It is also known the use of certain surfactants on the basis of sulfates alkoxysilane alcohols. These materials are used individually, also have disadvantages under very harsh conditions of salinity, hardness and temperature, partly due to the fact that certain surfactant sulphates alkoxysilane alcohols are unstable at high temperatures, i.e., above about 70°C.

Summary of the invention

In one embodiment, hydrocarbons may be produced from hydrocarbon-containing formation containing crude oil, the method comprising stages, in which process at least part of a hydrocarbon layer of the composition for the extraction of hydrocarbons, which consists of internal reincorporate with high molecular weight and a viscosity reducing compound. This material is effective in the range of salinity from about 1% by weight or less to about 10% by weight or higher, and at temperatures ranging from about 40 to 140°C.

The present invention provides a method of treatment of these crude oil containing reservoir, which comprises the steps in which (a) serves an arrangement for the extraction of hydrocarbons in at least a portion of the crude oil containing formation, wherein the composition includes an internal reincorporate (IOS) with high�Oh molecular weight and at least one of a viscosity reducing compound; and (b) provide for the composition to interact with hydrocarbons in the hydrocarbon formation. Internal reincorporate high molecular mass may include internal C15-18-reincorporate, internal C19-23-reincorporate, inner C20-24-reincorporate, inner C24-28-reincorporate and mixtures thereof.

In one embodiment, the composition for the extraction of hydrocarbons is fed into a hydrocarbon reservoir by mixing it with water and/or brine from the formation. The composition for the extraction of hydrocarbons preferably is from about 0.01 to about 2.0% by weight of the total amount of the mixture of water and/or brine/composition for the extraction of hydrocarbons" (injected fluid). More important is the number of actual active matter that is present in the inlet fluid, the active substance is a surfactant, here the internal(-tion) reincorporate(-you)). Thus, the number of internal reincorporate in the inlet fluid may be from about 0.05 to about 1.0% by weight, preferably from about 0.1 to about 0.8% by weight. Then injected the fluid is pumped into a hydrocarbon reservoir.

In one embodiment, the hydrocarbon composition may be p�obtained from hydrocarbon-containing formation. Hydrocarbon-containing composition may include any combination of hydrocarbons, internal reincorporation, methane, water, carbon monoxide and ammonia.

Brief description of the drawings

Fig. 1 depicts one embodiment of processing hydrocarbon-containing formation;

Fig. 2 depicts one embodiment of processing hydrocarbon-containing formation.

While the invention is susceptible to various modifications and alternative forms, specific embodiments of it are shown by way of example in the drawings and will be described in detail here. It should be understood that the drawing and detailed description are not intended limit the invention to the particular disclosed form, but, on the contrary, the invention should cover all modifications, equivalents and alternatives falling within the meaning and scope of the present invention, as defined in paragraphs appended claims.

Detailed description of embodiments of the invention

"Average carbon number" as here used, is determined by multiplying the number of carbon atoms in each internal reincorporate in a mixture of internal reincorporates on the content of this internal reincorporate in mole percent, and then the addition of works.

"Inner C15-18-retinal�eat", as used here, means a mixture of internal reincorporation, wherein the mixture has an average carbon number from about 16 to about 17 and at least 50% by weight, preferably at least 75% by weight, most preferably at least 90% by weight of internal reincorporated in the mixture contain from 15 to 18 carbon atoms.

"Inner C19-23-reincorporate", as used herein, means a mixture of internal reincorporation, wherein the mixture has an average carbon number from about 21 to about 23 and at least 50% by weight, preferably at least 60% by weight, internal reincorporated in the mixture contain from 19 to 23 carbon atoms.

"Inner C20-24-reincorporate", as used here, means a mixture of internal reincorporation, wherein the mixture has an average carbon number of from about 20.5 to about 23 and at least 50% by weight, preferably at least 65% by weight, most preferably at least 75% by weight of internal reincorporated in the mixture contain from 20 to 24 carbon atoms.

"Inner C24-28-reincorporate", as used herein, means a mixture of internal reincorporation, wherein the mixture has an average carbon number from about 24.5 to 27, and at least 40% by weight, preferably at least 50% by weight, most of predpochtitel�but at least 60% by weight of internal reincorporated in the blend contain from 24 to 28 carbon atoms.

Hydrocarbons may be extracted from the hydrocarbon reservoir through the drilling of wells penetrating a hydrocarbon reservoir. "Hydrocarbons" generally defined as molecules formed primarily by carbon atoms and hydrogen, such as oil and natural gas. Hydrocarbons may also include other elements, such but not limited to those, as Halogens, metallic elements, nitrogen, oxygen and/or sulfur. Hydrocarbons obtained from a hydrocarbon formation may include, but are not limited to such, kerogen, bitumen, probatum, asphaltenes, resins, saturated hydrocarbon, naphthenic acids, oils or combinations thereof. Hydrocarbons may be located within mineral matrices or near them underground. Matrices may include, but are not limited to such, sedimentary rock, Sands, silicalite, carbonates, diatomite and other porous media.

"A layer" includes one or more hydrocarbon-containing layers, one or more containing hydrocarbon layer, overlying rock and/or underlying rock. "Covering rock and/or underlying rock formation" includes impermeable materials of one or more different types. For example, overlying/underlying rock may include rock, shale, mudstone or.�roncemay carbonate (i.e., impermeable carbonate without hydrocarbons). For example, underlying rock may contain shale or mudstone. In some cases, overlying/underlying rock may have some permeability. For example, underlying rock may consist of permeable mineral, such as Sandstone or limestone. In some versions, at least part of the hydrocarbon-containing formation may be located at a depth of not less than or more than 1,000 feet (305 m) below the ground surface.

Properties of hydrocarbon reservoir can influence how hydrocarbons flow through overlying/underlying rocks to one or more productive wells. Properties include, but are not limited to such, mineralogical composition, porosity, permeability, pore distribution by size, surface area, salinity or temperature of formation. The properties of the overlying/underlying rocks in combination with the properties of hydrocarbons, such as characteristics of the capillary pressure (static) and the characteristics of the relative permeability (flow-through), can influence the advancement of hydrocarbons through a hydrocarbon reservoir.

The permeability of the hydrocarbon-containing formation may vary depending on the composition of the formation. Relatively permeable formation �may include heavy hydrocarbons, captured, for example, sand or carbonate. "Relatively permeable", as used here, has to do with the layers or parts thereof, which have an average permeability of 10 millidarcy or more. "Relatively low permeability", as used here, has to do with the layers or parts thereof, which have an average permeability of less than about 10 millidarcy. One Darcy is equal to about 0,99 square micrometer. Impermeable portion of a layer mainly has a permeability of less than about 0.1 millidarcy. In some cases, part or all of the amount of hydrocarbon contained in a relatively permeable formation may include mainly heavy hydrocarbons and/or tar without supportive framework mineral grains, and only floating (or no) mineral matter (e.g., asphalt lakes).

In a hydrocarbon reservoir can be in fluid (e.g., gas, water, hydrocarbons, or combinations thereof) with different densities. The mixture of fluids in the hydrocarbon layer can form between layers overlying and underlying rocks according to the density fluids. Gas can form the top layer, the hydrocarbon may be the middle layer, and the water can form the bottom layer in the hydrocarbon reservoir. Fluids may�to otstavat in the hydrocarbon reservoir in a variety of quantities. The interaction between the fluids in the reservoir can create the interface, or boundary, between fluids. The interface, or boundary, between the fluids and the reservoir can be created due to interactions between the fluids and the formation. Typically, the gases do not form boundaries with other fluids in the hydrocarbon reservoir. In one embodiment, the first boundary may form between a water layer and underlying bedrock. The second boundary may form between a water layer and a layer of hydrocarbons. The third boundary may occur between the hydrocarbons with different densities in the hydrocarbon reservoir. In some embodiments, the execution in the hydrocarbon layer may be present numerous fluids with numerous borders. It should be clear that in a hydrocarbon reservoir can be many combinations of boundaries between fluids and overlying/underlying rocks.

Production fluids may disrupt the interaction between fluids and between fluids and overlying/underlying rocks. When the fluid is removed from the hydrocarbon layer, the various layers of the fluids can be mixed to form the layers of the mixed fluids. Smeshnyuchaya environment can exhibit different interaction at the boundaries of the mixed fluids. Depending on the interactions at the boundaries of the mixed fluids, hydrocarbon production may become difficult. Quantitative assessment of interactions (e.g., energy level) at the interface between fluids and/or fluids, and overlying/underlying rocks may be useful for predicting the progress of hydrocarbons through a hydrocarbon reservoir.

Quantification of the energy required for interactions (e.g., mixing) between the fluids within the reservoir at the interface can be difficult to measure. Quantification of energy levels at the interface between the fluids can be carried out by generally known methods (for example, using the tensiometer with a rotating drop, tape weights (cuvette) Langmuir). Characteristics of the interaction energy at the interface can be called interfacial surface tension. "Interfacial tension" as used here, is related to the free energy of the surface, which occurs between two or more fluids, between which the boundary occurs. A high value of interfacial surface tension (for example, more than than about 10 Dyne/cm (10-2N/m)) may indicate the inability of the fluid to mix with Deut�th the fluid with the formation of the emulsion fluids. As used herein, "emulsion" refers to a dispersion of one immiscible fluid in the second fluid when adding a composition that reduces interfacial surface tension between fluids before reaching stability. The inability of fluids to be mixed may be due to the high energy of the interfacial surface tension between two fluids. Low values of interfacial surface tension (e.g., less than about 1 Dyne/cm (10-3N/m)) may indicate a lower surface interaction between two immiscible fluids. The smaller surface energy of interaction between two immiscible fluids may be the result of mixing of two fluids with the formation of the emulsion. Fluids with low values of interfacial surface tension can be set in motion to the trunk of a borehole due to reduced capillary forces and therefore extracted from hydrocarbon-containing formation.

Fluids in the hydrocarbon layer can be moistened (e.g., to adhere to overlying/underlying rock, or spread on overlying/underlying rock in the hydrocarbon reservoir). As used herein, "wettability" refers to the preferred�th ability of a fluid to spread over a solid surface or adhere to it in the presence of other fluids. Methods for determining the wettability of a hydrocarbon formation are described by the author Craig, Jr. in the work "The Reservoir Engineering Aspects of Waterflooding" ("Applied aspects of waterflooding of stratified reservoirs"), 1971, Volume 3 (monograph series publisher Society of Petroleum Engineers, which is here incorporated by reference. In one embodiment, hydrocarbons may adhere to the Sandstone in the presence of gas or water. Overlying/underlying rock, which is basically covered with hydrocarbons, can be designated as "oil wetted". Overlying/underlying rock can be wetted with oil due to the presence of polar and/or surface-active components (e.g., asphaltenes) in the hydrocarbon-containing formation. The composition of the layer (e.g., silica, carbonate, or clay) can determine the amount of adsorption of hydrocarbons to the surface overlying/underlying sediments. In some embodiments, execution of the porous and/or permeable formation may allow hydrocarbons to more easily wet the overlying/underlying rock. Essentially wetted by oil overlying/underlying rock can suppress the extraction of hydrocarbons from hydrocarbon-containing formation. In certain versions wetted by the oil phase hydrocarbon-containing formation may be located at a depth of not less than or more than 1,000 feet (305 meters) below the surface�knosti of the earth.

The hydrocarbon layer may include water. Water can interact with the surface of the underlying rocks. As used here, the term "wet water" is related to the formation of the shell from the water on the surface of the overlying/underlying sediments. Wetted with water overlying/underlying rock can stimulate the recovery of hydrocarbons from the formation that prevents wetting hydrocarbons overlying/underlying sediments. In certain versions wetted by the water phase hydrocarbon-containing formation may include small amounts of polar and/or surface-active components.

The water in the hydrocarbon reservoir may contain minerals (for example, minerals containing barium, calcium or magnesium) and mineral salts (e.g. sodium chloride, potassium chloride, magnesium chloride). Salinity, pH and/or hardness of the water in the reservoir can affect the extraction of hydrocarbons in the hydrocarbon formation. As used herein, "salinity" refers to the amount of solids dissolved in water. "Water hardness", as used here, is related to the concentration of divalent ions (e.g. calcium, magnesium) in water. The salinity and hardness of water can be determined using well known methods (for example, the specific electrical conductivity�, titration). When the salinity of the water in the hydrocarbon reservoir is increased, the interfacial tension between hydrocarbons and water may increase, and production fluids may be complicated.

The hydrocarbon-containing formation may be selected for treatment on the basis of such factors, but not limited to those, as the thickness of the hydrocarbon-containing layers within the reservoir, the estimated content is available for fluid production, the location of the reservoir, the salinity level of the formation, the temperature of the formation, and depth of hydrocarbon layer. At first, the natural reservoir pressure and temperature can be sufficient to ensure the flow of hydrocarbons into the barrels of drilling wells and to the surface. The temperature in the hydrocarbon layer can range from about 0°C to about 300°C, but are typically less than 150°C. the Composition according to the present invention is particularly advantageous when used at high temperature, since the internal reincorporate stable at such temperatures. When the hydrocarbons extracted from hydrocarbon-containing reservoir, pressure and/or temperature within the reservoir may be reduced. To continue the extraction of hydrocarbons from hydrocarbon-containing reservoir can be used various artificial forms under�EMA (for example, pumps, gas injection) and/or heating. The desirable extraction of hydrocarbons from hydrocarbon-containing reservoir may become uneconomical when the hydrocarbons are depleted in the reservoir.

Mobilization of residual hydrocarbons retained in the hydrocarbon formation may be difficult due to the viscosity of the hydrocarbons and capillary effects fluids in the pores of the hydrocarbon-containing formation. As used herein, "capillary forces" are related to the forces of attraction between fluid-fluid and at least part of a hydrocarbon-containing formation. In one embodiment, capillary forces may be overcome by increasing the pressure inside the hydrocarbon-containing formation. In other embodiments, execution of the capillary forces can be overcome by reducing the interfacial surface tension between fluids in the hydrocarbon reservoir. The ability to reduce the capillary forces in the hydrocarbon formation may depend on a number of factors, including but not limited to such, the temperature of the hydrocarbon-containing formation, the salinity of the water in the hydrocarbon-containing formation, and composition of hydrocarbons in the hydrocarbon formation.

When the production rates are reduced, additional methods can be applied to make hydrocarbon p�AST more economically viable. The methods may include the addition of sources of water (e.g., brine, steam), gases, polymers, monomers, or any combination thereof, in a hydrocarbon formation to increase the mobility of hydrocarbons.

In one embodiment, the hydrocarbon-containing formation may be treated with flooding water. Flooding can include the injection of water into the hydrocarbon portion of the reservoir through injection wells. Flooding at least part of the reservoir can moisten the portion of the hydrocarbon-containing formation. In the water-wetted portion of the hydrocarbon-containing formation by known methods may be increased pressure, and a mixture of water and hydrocarbons can be collected using one or more production wells. However, the water layer may not be effectively mixed with the hydrocarbon layer. Poor mixing efficiency may be due to the high interfacial surface tension between water and hydrocarbons.

The extraction of hydrocarbon-containing reservoir can be intensified processing of hydrocarbon-containing polymer layer and/or a monomer that can promote the hydrocarbons to one or more productive wells. The polymer and/or monomer may reduce the mobility of the water phase in the pores of the hydrocarbon-containing formation. The decreased mobility of water may allow uglevodorov�am more easily navigate through a hydrocarbon reservoir. Polymers include, but are not limited to such, polyacrylamides, partially hydrolyzed polyacrylamides, polyacrylates, ethylene copolymers, biopolymers, carboxymethylcellulose, polyvinyl alcohol, polystyrenesulfonate, polyvinylpyrrolidone, AMPS (2-acrylamido-2-methylpropanesulfonate), or combinations thereof. Examples of ethylene copolymers include copolymers of acrylic acid and of acrylamide, acrylic acid and laurelcrest, laurelcrest and acrylamide. Examples of biopolymers include xanthan gum and guar gum. In some embodiments, execution of the polymers can be subjected to crosslinking in situ in the hydrocarbon reservoir. In other embodiments, execution of the polymers can be generated in situ in the hydrocarbon reservoir. Polymers and obtaining polymers for use in oil production are described in U.S. patent No. 6427268 in the name of Zhang and others, entitled "Method For Making Hydrophobically Associative Polymers, Methods of Use and Compositions" ("Method of producing hydrophobic associated polymers, methods of use and compositions"; U.S. patent No. 6439308 in the name of Wang, entitled "Foam Drive Method" ("Method of oil displacement by foam"); U.S. patent No. 5654261 in the name of Smith, entitled "Permeability Modifying Composition For Use In Oil Recovery" ("Composition for modifying the permeability for use in oil production"); U.S. patent No. 528 4206 addressed Surles, etc., entitled "Formation reating" ("Processing layer"); the U.S. patent 5199490 in the name Surles, etc., entitled "Formation Treating" ("Processing layer"), and in U.S. patent No. 5103909 in the name Morgenthaler, etc., entitled "Profile Control In Enhanced Oil Recovery" ("Control profile in a tertiary method of oil recovery"), all of which are included here by reference.

The composition for the extraction of hydrocarbons

In one embodiment, the composition for the extraction of hydrocarbons can be summed up in a hydrocarbon reservoir. In the present invention the composition includes a specific internal reincorporate or a mixture of internal reincorporation. Internal reincorporate chemically suitable for EOR because they show little tendency to the formation of ordered structures of liquid crystals (which may constitute a major problem because the ordered structures tend to cause plugging of the structure of rocks in the hydrocarbon layer), since they are complex mixtures of surfactants with different chain length. Internal reinsurance exhibit a low tendency to adsorb on the surfaces of rocks in the injection tank, due to the repulsion of negative charges on the surface and negative charges in the surface-active substance. The use of alkalies further reduces the tendency of surfactants adsorbed to and reduces losses that means that can be used to lower the concentration of surfactant, making the method more economical.

As discussed in detail above, the present invention is especially useful in hydrocarbon formations that contain crude oil. The composition for the extraction of hydrocarbons according to the present invention is designed to create the best composition for extraction on the basis of internal reincorporates.

Internal olefin is an olefin, the double bond of which is localized somewhere along the carbon chain except the terminal carbon atoms. Linear internal olefin has no alkyl, aryl or alicyclic branching on any of the carbon atoms with double links or on any of the carbon atoms adjacent to the carbon atoms connected by a double bond. Typical products commercially available on the market obtained by the isomerization of alpha-olefins, are mainly linear and contain low average number of branches per molecule.

The composition for the extraction of hydrocarbons also include a viscosity reducing compound. This compound can be any compound that reduces the viscosity of the surfactant, but preferably it is a compound, which was reduced�t viscosity, the composition can be transported, pumped and injected into a hydrocarbon reservoir.

A viscosity reducing compound may be a nonionic surfactant, alcohol, ether alcohol or a mixture thereof. A viscosity reducing compound preferably represents C2-C17-alcohol, ethoxylated With2-C12-alcohol, 2-butoxyethanol, butyl ether of diethylene glycol or a mixture thereof. A viscosity reducing compound may be selected from the group consisting of ethanol, isobutyl alcohol, sec-butyl alcohol, 2-butoxyethanol, butyl simple ether of diethylene glycol or their mixtures.

In the preferred embodiment, a viscosity reducing compound is added in an amount of from 5% to 25%, calculated as the percentage of active substances.

In the most preferred embodiment, a viscosity reducing compound is added in an amount of from 5% to 15%, calculated as the percentage of active substances.

The remainder of the composition may include, but is not limited to such, water, organic solvents, sulfonates, arylsulfonate, brine or combinations thereof. Organic solvents include, but are not limited to these, methyl ethyl ketone, acetone, lower alkylalcohol, lower acylcarnitine or a combination thereof.

Receiving�their compositions for the extraction of hydrocarbons

Internal olefins, which are used to produce internal reincorporated according to the present invention may be produced by skeletal isomerization. Suitable methods of obtaining internal olefins are described in U.S. patents 5510306, 5633422, 5648584, 5648585, 5849960, and in European patent EP 0830315 B1, all of which are included here by reference in its entirety. The flow of hydrocarbons comprising at least one linear olefin, in contact with a suitable catalyst, such as catalytic zeolites described in the aforementioned patents, in the vapor phase at a suitable reaction temperature, pressure and volumetric flow rate. Basically, suitable reaction conditions include a temperature of from about 200 to about 650°C, the partial pressure of olefin is higher than about 0.5 atmosphere (0,05 MPa), and the total pressure from about 0.5 to about 10.0 atmospheres (0.05 to 1.0 MPa) or higher. Internal olefins according to the present invention preferably receives at a temperature in the range from about 200 to about 500°C, at a partial pressure of the olefin from about 0.5 to 2 atmospheres (0.05 to 0.2 MPa).

It is well known that internal olefins are more difficult to form sulfonates, than alpha-olefins (see job log "Tenside Detergents", vol. 22 (1985), No. 4, pp. 193-195). The article, entitled "Why Internal Olefins are Difficult to Sulfonate" ("Why on internal�ephiny difficult to alfirevich"), the authors point out that at various sulfonation of internal olefins obtained in industry and in the laboratory, using the reactor falling film, internal olefins gave the degree of conversion is below 90 percent, and additionally they report that found a need to increase the molar ratio of "SO3: internal olefin" more than 1.6:1, to achieve the degree of conversion of over 95 percent. In addition, these products obtained had a very dark color and contain high levels of di - and polysulfonic products.

U.S. patent 4183867 and 4248793, which are here incorporated by reference, represent the ways that can be used to obtain branched internal reincorporated according to the invention. They can be conducted in the reactor falling film to obtain a light-colored internal reincorporation. Amount of unreacted internal olefins in these ways constitute between 10 percent and 20 percent, and at least 20 percent, respectively, and to remove unreacted internal olefins must be taken special measures. Internal reincorporate containing between 10 percent and 20 percent, and at least 20 percent, respectively, unreacted internal olefins, should be cleaned before using them. So�way, getting internal reincorporate having desirable light color, and with the desired low content of free oil, presents considerable difficulties.

Such difficulties can be avoided with the following method, as disclosed in European patent EP 0351928 B1, which is incorporated herein by reference.

Method that can be applied for obtaining internal reincorporate for use in the present invention, includes a stage in which the reaction is carried out in a film reactor an internal olefin as described above with a sulfonating reagent in a molar ratio of sulfonating reagent to internal olefin of 1:1 to 1.5:1, while cooling the reactor with a cooling means having a temperature not exceeding 60°C, hold direct neutralization obtained in the stage of sulfonation of the reaction product, and, without isolation of unreacted internal olefin is subjected to hydrolysis of the neutralized reaction product.

Upon receipt of the sulfonates formed from internal olefins, internal olefins react with the sulfonating reagent, which may be a sulfur trioxide, sulfuric acid or oleum, with the formation of beta-sultone and some alkanesulphonic acids. Film reactor preferably is a reaction�'or falling film.

The reaction products are subjected to neutralization and hydrolysis. Under certain circumstances, for example, maintaining, beta-sultone is converted to gamma-sultone that can be converted into Delta-sultone. After neutralization and hydrolysis are obtained gamma hydroxysulphate and Delta hydroxysulphate. The lack of these two Sultonov is that they are very difficult to hydrolysis than beta sultone. Thus, in many versions, it is preferable to do without curing. beta Sultone give after hydrolysis of beta-hydroxysulphate. These materials should not be removed because they form a useful surface-active structure.

Coolant additive, which preferably is a water that has a temperature not exceeding 60°C, especially a temperature in the range from 0 to 50°C., depending on the circumstances, can also be used to lower the temperature.

Then the reaction mixture is fed into the unit for neutralization and hydrolysis. Neutralization/hydrolysis is carried out using a water-soluble base, such as sodium hydroxide or sodium carbonate. Suitable also appropriate grounds on the basis of potassium or ammonium. Neutralization of the reaction product from the reactor falling film mainly carried out from�itCOM grounds calculated on the acid component. Basically, the neutralization is carried out at a temperature in the range of 0 to 80°C. the Hydrolysis can be carried out at a temperature in the range from 100 to 250°C, preferably from 130 to 200°C. the Duration of hydrolysis basically can be from 5 minutes to 4 hours. Alkaline hydrolysis can be carried out with the use of hydroxides, carbonates, bicarbonates of alkali (alkaline earth) metals, and amine compounds.

This process can be carried out in a periodic, semi-continuous or continuous mode. The reaction is generally carried out in the reactor falling film, which is cooled by passing a flow of coolant along the outer walls of the reactor. On the inner walls of the reactor an internal olefin flows in a downward direction. The sulfur trioxide is introduced into the reactor is diluted in a stream of nitrogen, air or any other inert gas. The concentration of sulfur trioxide mostly varies between 2 and 5 percent by volume, based on the volume of carrier gas. When receiving an intercom reincorporate formed from olefins according to the present invention, it is necessary that at the stage of neutralization and hydrolysis was achieved very close mixing of the product from the reactor and water base. This can be done, for example, by vigorous stirring or by adding polar�th cerastoides (such as a lower alcohol), or the addition of a phase transfer agent.

Typical composition of domestic reincorporate include about 30-35% of the active substance (internal reinsurance) in water. It is desirable to obtain a composition of internal reincorporate so that the percentage content of active substance is maintained as high as possible, which composition is hereinafter referred to as surface-active composition is highly active substances. In terms of concentration of active substance preferably to at least 40%, preferably at least 50%, and more preferably at least 60%. The concentration of active substance can be in the range from 45% to 95%, preferably in the range from 60% to 80%.

Surface-active composition is usually transported from the place of receipt to the location of the hydrocarbon reservoir. Highly active surfactants are very difficult to pump or handle, and they can be in the form of a paste or a non-flowing gel. While it is desirable to reduce the level of water content, which is transported together with surface-active substance, it is also desirable to be able to pump or otherwise transport a surfactant. The present invention provides a composition which has� a high concentration of active substances, but also can be pumped and transported.

To reduce the viscosity of highly active surfactants, surface-active composition after its preparation and before its transportation to the location of the hydrocarbon reservoir add a viscosity reducing compound.

Injection of the composition for the extraction of hydrocarbons

The composition for the extraction of hydrocarbons can interact with hydrocarbons in at least part of the hydrocarbon-containing formation. Interaction with the hydrocarbons may reduce the interfacial tension of the hydrocarbons with one or more fluids in the hydrocarbon reservoir. In other embodiments, execution of the composition for the extraction of hydrocarbons may reduce interfacial surface tension between the hydrocarbons and overlying/underlying rock in the hydrocarbon reservoir. The decline in interfacial surface tension can ensure the promotion of at least part of the hydrocarbons through a hydrocarbon reservoir.

The ability of the composition for the extraction of hydrocarbons to reduce interfacial surface tension of a mixture of hydrocarbons and fluids can be estimated using known methods. In one embodiment, the value of interfacial surface tension d�I mixture of hydrocarbons and water can be determined using a tensiometer with a rotating drop. To a mixture of the hydrocarbon/water" can be added to the amount of the composition for the extraction of hydrocarbons, and may be determined by the value of the interfacial surface tension obtained for the fluid medium. A low value of interfacial surface tension (e.g., less than about 1 Dyne/cm (10-3N/m)) may indicate that the composition is lowered at least some of the energy surface between hydrocarbons and water. The reduction of surface energy may indicate that at least part of the mixture of the hydrocarbon/water" can move at least a portion of the hydrocarbon-containing formation.

In one embodiment, the composition for the extraction of hydrocarbons, may be added to a mixture of the hydrocarbon/water", and can be determined the value of the interfacial surface tension. Interfacial surface tension is preferably less than about 0.1 Dyne/cm (10-4N/m)). Ultra-low interfacial surface tension (e.g., less than about 0.01 Dyne/cm (10-5N/m)) can show that the composition for the extraction of hydrocarbons is reduced at least part of the surface tension between the hydrocarbons and water so that at least a portion of the hydrocarbons can move at least a portion of the hydrocarbon-containing formation. At least an hour�ü hydrocarbons can more easily move at least part of a hydrocarbon layer at ultralow interfacial surface tension, than the hydrocarbons that have been treated with composition, which leads to the value of interfacial surface tension, greater than 0.01 Dyne/cm (10-5N/m) for fluids in the reservoir. The addition of the composition for the extraction of hydrocarbons by flowing the hydrocarbon-containing environments in the reservoir, which leads to the low value of interfacial surface tension, can improve the efficiency with which the hydrocarbons can be extracted. The concentration of the composition for the extraction of hydrocarbons in the hydrocarbon formation may be minimized to reduce to a minimum the costs of the application during production.

In one embodiment, the method of processing hydrocarbon-containing formation, the composition for the extraction of hydrocarbons comprising an inner reincorporate and a viscosity reducing compound, may be introduced (e.g., injected) into hydrocarbon-containing formation 100 through injection well 110 as depicted in Fig. 1. Hydrocarbon reservoir 100 may include covering the breed 120, hydrocarbon layer 130 and the underlying rock 140. Injection well 110 may include openings 112 that allow fluid media to flow through the hydrocarbon reservoir 100 at various levels of depth. In certain embodiments, execution of the hydrocarbon layer 130 may be on HL�Binet less than 1000 feet (305 m) below the earth's surface. In some embodiments, execution of the underlying rock 140 hydrocarbon-containing formation 100 may be wetted with oil. In other versions in the hydrocarbon-containing formation 100 may be water with low salinity.

The composition for the extraction of hydrocarbons may be introduced into the formation in an amount calculated on the hydrocarbons present in the hydrocarbon-containing formation. However, the amount of the composition for the extraction of hydrocarbons may be too small for accurate delivery in a hydrocarbon formation using known methods of delivery (e.g., by pumping). To facilitate delivery of small quantities of the composition for the extraction of hydrocarbons in a hydrocarbon layer of the composition for the extraction of hydrocarbons may be combined with water and/or brine for receiving pumped fluid.

In one embodiment, the composition for the extraction of hydrocarbons is fed into a formation containing crude oil with heavy components, mixing it with brine from the formation from which hydrocarbons were extracted, or fresh water. The mixture is then injected into the hydrocarbon formation.

In one embodiment, the composition for the extraction of hydrocarbons is fed into a hydrocarbon reservoir by mixing 100 EEC brine from the reservoir. The composition for the extraction of hydrocarbons preferably is from about 0.01 to about 2,00% by weight of the total amount of the mixture of water and/or brine/composition for the extraction of hydrocarbons" (injected fluid). More important is the amount of actual active matter that is present in the inlet fluid, the active substance is a surfactant, here the inner reincorporate or containing a mixture). Thus, the number of internal reincorporate in the inlet fluid may be from about 0.05 to about 1.0% by weight, preferably from about 0.1 to about 0.8% by weight. Could be used more than 1.0% by weight, but it likely would increase costs without improving efficiency. Then injected the fluid is pumped into a hydrocarbon reservoir.

The composition for the extraction of hydrocarbons may

to interact with at least part of the hydrocarbons in hydrocarbon layer 130. The interaction of the composition for the extraction of hydrocarbons from the hydrocarbon layer 130 may reduce at least a portion of the interfacial surface tension between different hydrocarbons. The composition for the extraction of hydrocarbons may also reduce at least a portion of the interfacial surface tension between one or more t�cochimi environments (e.g., water, hydrocarbons) in the formation and underlying rock 140, one or more fluids in the reservoir and the cap rock 120, or a combination thereof.

In one embodiment, the composition for the extraction of hydrocarbons can interact with at least part of the hydrocarbons and at least part of one or more fluids into the formation, to reduce at least part of the interfacial surface tension between the hydrocarbons and one or more fluids. The decline in interfacial surface tension may allow at least part of the hydrocarbons to form an emulsion with at least part of one or more fluids in the reservoir. The value of the interfacial surface tension between the hydrocarbons and one or more fluids may be changed by action of the composition for the extraction of hydrocarbons to a value of less than about 0.1 Dyne/cm (10-4N/m)). In some versions, the value of the interfacial surface tension between the hydrocarbons and other fluids in the reservoir can be reduced by a composition for the extraction of hydrocarbons to a level less than about 0.05 Dynes/cm (5×10-5N/m)). In other versions, the value of the interfacial surface tension between the hydrocarbons and other fluids in the reservoir can be reduced composite�th for the extraction of hydrocarbons to a level less than 0.001 Dyne/cm (10 -6N/m).

At least part of the mixture composition for the extraction of hydrocarbons/hydrocarbon/fluid" can be made movable to a productive borehole 150. Products derived from the oil-production well 150 may include, but are not limited to such, the components of the composition for the extraction of hydrocarbons (e.g., long-chain aliphatic alcohol and/or salt of long-chain aliphatic acid), methane, carbon monoxide, water, hydrocarbons, ammonia, or combinations thereof. Extraction of hydrocarbons from hydrocarbon-containing formation 100 may be increased by more than about 50% after the composition for the extraction of hydrocarbons was added to the hydrocarbon-containing formation.

In certain embodiments, execution of the hydrocarbon-containing formation 100 may be pre-processed fluid medium for removal of hydrocarbons. Fluid for removal of hydrocarbons may consist of water, steam, brine, gas, liquid polymers, foamed polymers, monomers or their mixtures. Fluid for removal of hydrocarbons can be used for the treatment of the reservoir before the reservoir will be commissioned composition for the extraction of hydrocarbons. In some embodiments, execution of the hydrocarbon-containing formation 100 may be at a depth less than 1000 feet (305 m) from the earth's surface. In certain� versions fluid for removal of hydrocarbons can be heated before it is injected into a hydrocarbon reservoir 100. Fluid for removal of hydrocarbons may reduce the viscosity of at least part of the hydrocarbons within the reservoir. The viscosity reduction of at least part of the hydrocarbons in the reservoir can increase the mobility of at least part of the hydrocarbons to production well 150. After at least a portion of the hydrocarbons in the hydrocarbon-containing formation 100 has been made more mobile, the repeated injection of the same or other fluids for removal of hydrocarbons may become less effective in the mobilization of hydrocarbons through a hydrocarbon reservoir. The low efficiency of mobilization may be due to the fact that fluids for removal of hydrocarbons create a more permeable zones in the hydrocarbon-containing formation 100. Fluids for removal of hydrocarbons can pass through the permeable zones in the hydrocarbon reservoir 100 and not interact with the remaining hydrocarbons and to increase their mobility. Thus, the displacement of the heavier hydrocarbons adsorbed on the underlying rock 140, may be reduced. Eventually, the reservoir can be considered as marginal or uneconomic for production of hydrocarbons.

In certain versions, the injection of the composition for the extraction of hydrocarbons after treatment� hydrocarbon-containing reservoir of the fluid for removal of hydrocarbons may increase the mobility of heavier hydrocarbons, absorbed into the underlying rock 140. The composition for the extraction of hydrocarbons can interact with the hydrocarbons to reduce interfacial surface tension between the hydrocarbons and underlying rock 140. The decline in interfacial surface tension may be such that the hydrocarbons are mobile and are extracted from the oil-production well 150. In some embodiments, execution of the hydrocarbons produced from production well 150 may include at least a portion of the components of the composition for the extraction of hydrocarbons, the fluid for removal of hydrocarbons injected into the well for pretreatment, methane, carbon dioxide, ammonia, or combinations thereof. The addition of the composition for the extraction of hydrocarbons from at least part of the marginal hydrocarbon-containing formation may extend the period of operation of wells in the hydrocarbon reservoir. Extraction of hydrocarbons from hydrocarbon-containing formation 100 may be increased more than about 50% after the composition for the extraction of hydrocarbons was added to the hydrocarbon-containing formation. Increasing the production of hydrocarbons can increase the economic efficiency of the hydrocarbon-containing formation.

The interaction of the composition for the extraction of hydrocarbons from at least part of a carbohydrate�ODS in the formation may reduce at least a portion of the interfacial surface tension between the hydrocarbons and underlying rock 140. Reducing at least part of the interfacial surface tension can increase the mobility of at least part of the hydrocarbons through a hydrocarbon reservoir 100. However, the mobilization of at least part of the hydrocarbons may not reach economically advantageous extent.

In one embodiment, the hydrocarbon-containing formation 100, after treatment of the formation with a composition for the extraction of hydrocarbons, through injection well 110 can be injected polymers and/or monomers to increase the mobility of at least part of the hydrocarbons through the formation. Suitable polymers include, but are not limited to such, CIBA® ALCOFLOOD®, manufactured by Ciba Specialty Additives (Tarrytown, NY), Tramfloe® manufactured by Tramfloc Inc. (Temple, AZ), and polymers NOT®, manufactured by Chevron Phillips Chemical Co. (The-Woodlands, TX). The interaction between hydrocarbons, the composition for the extraction of hydrocarbons and the polymer can enhance the mobility of at least part of the hydrocarbons remaining in the formation to the production well 150.

Internal reincorporate composition is thermally stable and can be used in a wide range of temperatures. The composition for the extraction of hydrocarbons, may be added to the portion of the hydrocarbon-containing formation 100 that has an average temperature above about 70�C, due to the high thermal stability of the internal reinsurance.

In some embodiments, execution of the composition for the extraction of hydrocarbons may be combined with at least part of the fluid for removal of hydrocarbons (for example, water solutions of polymers) for the formation of the injected fluid. The composition for the extraction of hydrocarbons may be injected into the hydrocarbon-containing formation 100 through injection well 110 as depicted in Fig. 2. The interaction of the composition for the extraction of hydrocarbons with hydrocarbons in the formation may reduce at least a portion of the interfacial surface tension between the hydrocarbons and underlying rock 140. Reducing at least part of the interfacial surface tension can increase the mobility of at least part of the hydrocarbons to the selected section 160 in the hydrocarbon reservoir 100 with the formation of the basin 170 hydrocarbons. At least a portion of the hydrocarbons can be extracted from the pool 170 of hydrocarbons in the selected section of the hydrocarbon-containing formation 100.

In other embodiments, the execution of mobilizing at least some hydrocarbons in the selected section 160 may not achieve economically favorable degree. In the hydrocarbon-containing formation 100 may be injected polymers to improve mobility for less�St least part of the hydrocarbons through the formation. The interaction between at least part of the hydrocarbons, the composition for the extraction of hydrocarbons and polymers can enhance the mobility of at least part of the hydrocarbons to production well 150.

In some embodiments, execution of the composition for the extraction of hydrocarbons may include an inorganic salt (e.g., sodium carbonate (Na2CO3), sodium hydroxide, sodium chloride (NaCl) or calcium chloride (CaCl2)). The addition of inorganic salts can facilitate the dispersion of the composition for the extraction of hydrocarbons in the mixture the hydrocarbon/water". The increased dispersion of the composition for the extraction of hydrocarbons may weaken the interaction surface between the hydrocarbon and water. The use of alkali (e.g., sodium carbonate, sodium hydroxide) may prevent the adsorption of IOS on the rock surface and can create a natural surfactant with the components of crude oil. Weakened interaction can reduce interfacial surface tension of the mixture and to give the fluid, which is more mobile. The alkali may be added in an amount of from about 0.1 to 5% by weight.

Examples

Example 1

This example illustrates the use of a viscosity reducing compound to reduce the viscosity of the surface-active�x compositions of highly active substances. The results show the influence of the dilution solvent of highly active surfactants on the viscosity at 60 º C and a shear rate of 10 sec-1. Highly active surfactants were diluted to 25%, calculated as the percentage of the entire sample. The results are shown in Table 1. The viscosity was measured using Brookfield viscometer with spindle LV4.

tr>
Table 1
SurfactantTap waterEthanolIsobutyl alcoholthe sec-Butyl alcoholDGBE
IOS 24-28,
63% of active substance
18891 CPS833 CPS2540
CPS
833 CPS1746 CPS
IOS 20-24,
73% of active substance
10993 CPS1190 CPS1389
CPS
1389 CPS515
CPS
IOS 15-18,
77.5% of active substance
6270 CPS952 CPS2103
CPS
1150 CPS1666 CPS
DGBE = monopoloy simple ether of diethylene glycol

Example 2

This example illustrates the use of a viscosity reducing compounds to reduce the viscosity of highly active substances (66.3 percent) internal C19-23-reincorporate (IOS 19-23). This material had a viscosity of 4900 CPS (at 60 º C and a shear rate of 1 sec-1. The results show the effect of dilution with a solvent that IOS 19-23 on the viscosity at the temperature of 60 ° C and shear rate 1 sec-1. IOS 19-23 was diluted to 1, 5 and 10%, calculated as the percentage of active substances. The results are shown in Table 2. The viscosity was measured using Brookfield viscometer with spindle LV4.

Table 2
Additive (% dilution of the active substance)EGBEDGBEEthoxylated alcohol Neodol 91-8
1 6000 CPS4100 CPS4900 CPS
51700 CPS2500 CPS4800 CPS
101100 CPS1000 CPS4400 CPS
EGBE = 2-butoxyethanol
DGBE = monopoloy simple ether of diethylene glycol

1. The method for treating a formation containing crude oil, which includes stages, at which:
(a) serves an arrangement for the extraction of hydrocarbons in at least a portion of the crude oil containing formation, wherein the composition includes at least two internal reincorporate selected from the group consisting of internal C15-18-reincorporates, inner C19-23-reincorporates, inner C20-24-reincorporates and inner C24-28-reincorporate, and at least one of a viscosity reducing compound, which is an isobutyl alcohol, ethoxylated With2-C12-alcohol, 2-butoxyethanol, butyl ether of diethylene glycol or a mixture thereof; and
(b) provide for the composition to interact with hydrocarbons in �terasem crude oil reservoir.

2. A method according to claim 1, wherein the composition for the extraction of hydrocarbons serving in crude oil containing the first layer by mixing it with water and/or brine from the formation from which it was extracted crude oil, with the formation of the injected fluid, and the internal reincorporate is from 0.05 to 1.0% by weight, preferably from 0.1 to 0.8% by weight of the injected fluid, and then injected the fluid injected into the formation.

3. A method according to claim 1 or 2, wherein a viscosity reducing compound is selected from the group consisting of isobutyl alcohol, 2-butoxyethanol, butyl simple ether of diethylene glycol and their mixtures.

4. A method for reducing the viscosity of the composition of highly active surfactants having the concentration of active substance is from 30 to 95%, comprising a stage in which a composition comprising at least two internal reincorporate selected from the group consisting of internal C15-18-reincorporates, inner C19-23-reincorporates, inner C20-24-reincorporates and inner C24-28-reincorporate, in contact with a viscosity reducing compound to obtain a composition for the extraction of hydrocarbons, with a viscosity reducing compound represents a isobutyl alcohol, ethoxylated With2-C12-alcohol, 2-butoxy�tanol, butyl ether of diethylene glycol or a mixture thereof.

5. A method according to claim 5, in which a viscosity reducing compound is selected from the group consisting of isobutyl alcohol, 2-butoxyethanol, butyl simple ether of diethylene glycol and their mixtures.

6. A method according to claim 4 or 5, in which the composition is highly active surfactant has a concentration of active substance from 55 to 80%.

7. A method according to claim 4 or 5, in which a viscosity reducing compound is added in an amount from 5 to 25%, calculated as the percentage of active substances.

8. A method according to claim 4 or 5, in which a viscosity reducing compound is added in an amount of from 5 to 15%, calculated as the percentage of active substances.

9. A method according to claim 4 or 5, in which the internal composition of reinsurance includes With20-24IOS (internal reincorporate).

10. The composition for the extraction of hydrocarbons, which includes at least two internal reincorporate selected from the group consisting of internal C15-18-reincorporates, inner C19-23-reincorporates, inner C20-24-reincorporates and inner C24-28-reincorporate, and a viscosity reducing compound, which is an isobutyl alcohol, ethoxylated With2-C12-alcohol, 2-butoxyethanol, butyl ether, dieti�of angelicola or a mixture thereof.

11. A composition according to claim 10, in which a viscosity reducing compound is a butyl ether of diethylene glycol.

12. A composition according to claim 10 or 11, which also includes alkali in an amount of from 0.1 to 5% by weight.

13. A composition according to claim 10 or 11, in which the inner reincorporate includes With20-24IOS (internal reincorporate).

14. A composition according to claim 10 or 11, in which the inner reincorporate includes With19-23IOS (internal reincorporate).



 

Same patents:

FIELD: oil and gas industry.

SUBSTANCE: method involves hydrophobisation of pore space in bottom-hole zone rock with 0.5-25% solution of polymethylhydridosiloxane in organic liquid containing its polymerisation catalyst. The solution is pushed down into the reservoir by gaseous agent selected out of nitrogen, natural gas, exhaust gases of combustion engines. Gaseous agent is fed to the well at a pressure exceeding reservoir pressure at least by 1.0 MPa. After the solution is pushed down, the well is left for process aging for two days.

EFFECT: reduced water saturation of reservoir bottom-hole zone, enhanced gas well deliverability with single treatment of reservoir.

3 tbl

FIELD: oil and gas industry.

SUBSTANCE: method includes vibration impact on the oil reservoir by the resilient oscillation sources. For this on ground surface near the wellhead of the production well the oscillation sources of same frequency are installed. Near the external boundary of the specified well the oscillation sources of same but higher frequency are also installed. Simultaneous impact of oscillations from all sources on the oil reservoir is performed with intensity, time of impact and oscillations interference ensuring coagulation of oil drops in porous space of the oil reservoir with water and directed flow movement due to difference of frequencies of the oscillation sources towards wellhead of the production well. At that contracting effect of the directed flow movement towards the wellhead of the production well is specified by number of sources of the resilient oscillations in the external boundary of the production well.

EFFECT: increased oil extraction due to reduced filtration resistances during water-oil emulsion movement via the porous environment.

2 dwg, 1 ex

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to secondary methods of HC extraction from the underground reservoirs, in particular to methods of the hydraulic fracturing without the proppant, as well as to the selective injection to some underground reservoirs. As per the method the selective stratum of stratums set is isolated along the well bore in the underground section from rest stratums of the set. The selective injection is used to supply fluid to the selective stratum in the stratums set. At that the fluid is supplied to the selective stratum regardless of the fact weather the fluid was supplied to the neighbouring stratum of the stratums set. Isolation means isolation of the stratums set from pressure acting on the selective stratum when the fluid is supplied to the selective stratum. Hydraulic fracturing of each stratum of the stratums set is performed. Testing of the stepwise pressure variation is performed for at least one stratum of the stratums set. Testing of the stepwise pressure variation includes opening of one of the reservoir stratums in the stratums set by the fluid injection to the well bore. At that one of the stratums is opened at specified pressure. The fluid backflow is ensured such that one of the reservoir stratums is closed. Re-opening of the one of the reservoir stratums is performed for one or more times. At that the reservoir opening pressure is reduced each time. Mode is determined when the reservoir opening pressure is below the injection pressure at which the reservoir injection ensures the fluid supply to the stratums set. As response to determination that the reservoir re-opening pressure is below the injection pressure the test is completed by stepwise pressure variation.

EFFECT: increased efficiency of HC production.

21 cl, 7 dwg

FIELD: oil and gas industry.

SUBSTANCE: according to the method capital mining operations are carried out on penetration and developing access channels to a productive formation of a deposit. Underground mining and development operations and field operations on the well production of shale oil and gas are performed using multistaged hydraulic fracturing or thermal effect on the formation. A shale oil- and gas-containing deposit is penetrated by vertical shafts. Preparation of the productive formation for hydrocarbon production is carried out by the underground mining and development openings placed below a water-bearing horizon covering the rock above the shale rock of the deposit. Hydrocarbon production is carried out by mining blocks of underground producing wells with horizontal sections protruded in the formation. The producing wells are drilled from underground cells constructed mainly in the mining and development openings. Before complete hydraulic fracturing of the formation small diagnostic hydraulic fracturing of the formation is made in the producing wells of a small diameter, which are drilled mainly from the mining and development openings to the whole thickness of the productive formation transversely to its course. The product of the producing wells is divided in the shaft bottom into shale gas and shale oil. The shale oil is outputted to the surface for further treatment before delivery to consumers. The shale gas is burnt in the boiler of a shaft bottom heat-generating plant to generate water steam or hot water used for the production of electricity or for the purpose of a thermal effect on the productive formation in order to increase intensity and the production rate.

EFFECT: reduced total volume of operations on drilling producing wells while developing shale deposits.

2 cl, 11 dwg

FIELD: oil and gas industry.

SUBSTANCE: method involves the use of horizontal holes, the horizontal section of which passes through the oil formation at the minimum distance from the gas cap 1/2 thickness of the oil part. The branch with sealing of annular space directed upwards is formed, with crossing of gas-oil contact and opening of gas saturated part of the formation. Meanwhile the string is perforated with opening of the gas cap in two opposite sections of the well within the target formation. Control of flows of gaseous and liquid fluids in the well between various perforation intervals is performed using the bypasses adjustable from the surface. The well design according to the method allows to perform independent gas recovery in required volumes from two intervals of gas cap opening, that allows independently to monitor the movement of the gas-oil contact and lift the formation fluid to the surface at the expense of natural gas-lift.

EFFECT: increase of level of development of oil stocks by means of control of intraformational cross-flows of gaseous fluid and minimizing of risks of coning, decrease of expenses for lifting of formation fluids to the surface at the expense of natural gas-lift.

6 cl

FIELD: oil and gas industry.

SUBSTANCE: according to the method intervals of a well are completed opposite the gas-saturated part, so called gas cap, and oil-saturated part of a productive stratum. A tubing string is run in to the well. The gas cap is isolated by a packer. Gas is injected to the gas-saturated part of the productive stratum and the product is extracted by a borehole pump. Simulated completion opposite the gas-saturated part of the productive stratum is ensured by the creation of drainage channels oriented radially inward the stratum. Then two coaxially mounted tubing strings of a different diameter are run in to the well. The tubing string with a lesser diameter is run in to the level of the oil-saturated part of the stratum and equipped with the borehole pump connected by an exhaust line to the ground separator intended for the separation of associated gas. The tubing string with a bigger diameter is run in to the level of the gas-saturated part of the stratum and connected to a pressure line of the separated associated gas from the ground gas compressor. Oil is extracted through the tubing string of a lesser diameter. Injection of the separated gas is made through the tubing string of a bigger diameter. At that the separated gas under pressure is delivered to a space between packers in the gas-saturated part of the stratum over gas-oil contact (GOC) thus supporting energy of the stratum at a permanent level. As far as to oil extraction from the oil-saturated part of the stratum and injection of the separated gas to the gas-saturated part of the stratum, GOC boundary is shifted stage by stage as per the thickness of the stratum from its roof to the bottom thus ensuring the gradual oil draw-down rate.

EFFECT: reduced labour costs at implementing associated gas injection to oil wells in order to maintain the reservoir pressure during operation of hydrocarbon deposits and improvement of their productivity.

1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: drilling of new wells or selection of drilled wells is executed. Several pumps are lowered in the well. Note here that in terrigenous or carbonate bed oil afflux to every productive well horizontal hole is predefined. Horizontal boreholes that differ in oil yield by 20% and more are selected. Pumps are lowered on parallel strings in horizontal borehole in length smaller than 300 m. Pumps are lowered on parallel strings in horizontal borehole in length over 300 m. Spacing between pumps does no 30 m. Every horizontal borehole is arbitrarily divided into three sequential sections. Pumps with output 2-10 times higher than that of pumps in section at horizontal borehole end are lowered at the central section.

EFFECT: accelerated oil extraction, uniform development, higher bed oil yield.

2 cl, 1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: drilling of new wells or selection of drilled wells are executed. Intervals of productive bed are isolated. Pump is lowered in the well. Selected sections are separated by packers. Well products are extracted from every said section. At development of terrigenous or carbonate bed the afflux profile is predetermined. Sections with afflux profile are revealed that differ in specific oil yield by 20% and more. Packers are fitted at points of specific yield variation. One pump is lowered on separate tubing or coiled tubing to the centre of every section. Spacing between lowered pumps over horizontal holes is set not to exceed 200 m.

EFFECT: accelerated oil extraction, uniform development, higher bed oil yield.

2 ex, 2 dwg

FIELD: oil and gas industry.

SUBSTANCE: at an oil deposit development oil is extracted through production wells and water is injected through injection wells in a cyclic mode. The cyclic mode is performed at individual injection wells fed with water from a group pumping station. At the remaining injection wells the permanent injection pressure is maintained. In the cyclic mode periodical limitation of water injection is set for the individual injection wells by complete or partial cut-off of a headrace with respective limitation of the injected water. Pumps of the group pumping station are set to the mode of the permanent pressure maintenance at the station output. An electric drive of the pumps is made partially regulated. At that a non-linear reversed algorithm is used for frequency regulation of the pumps electric current depending on the pressure at the output of the group pumping station. When the consumption rate of a working agent is reduced and the pressure is increased in the pump flow line the frequency of the electric pump feeding current is reduced as per a non-linear dependence till the preset pressure is obtained at a flow line of the group pumping station. When the consumption rate of the working agent is increased and the pressure is decreased in the pump flow line the frequency of the electric pump feeding current is increased till the preset pressure is obtained at the flow line of the group pumping station. The duration of the headrace cut-off is defined as the time required for the stoppage of the fluid flows movement in in-situ conditions within limits of the injection well impact. The duration of the complete or partial cut-off of the headrace is an assigned period of at least 2 hours and less than 4 hours per day. The complete or partial cut-off of the headrace is assigned with consideration of the time for control of the electric network power.

EFFECT: improved efficiency of the method due to the ensured optimal mode of water injection at water flooding and reduction of costs for oil production.

1 ex

FIELD: oil and gas industry.

SUBSTANCE: method of a well bore zone treatment for a productive formation that includes running in of an in-series bottom-up mounted hydroimpulsive device and a jet pump at the pipe string to the well. Fluid is delivered to the hydroimpulsive device and this fluid is used for an impact on the well bore treatment zone with simultaneous pumping the fluid with colmatage particles by the jet pump to the surface. A depth gauge is mounted additionally at the tubing string in front of the hydroimpulsive device. At that a rotary hydraulic vibrator is used as the hydroimpulsive device to create a water jet and pulse-cavitating flow along the perforation interval. An impact on structures of the formation with fluid is made by the excitation of resonant oscillation of the fluid column in the well due to matching of the ripple frequency of the rotary hydraulic vibrator and own resonance frequency of the casing string with the fluid, placed below the rotary hydraulic vibrator and being a resonator of an organ pipe type. The required oscillation frequency f, Hz, is determined by the specified mathematical expression.

EFFECT: improved efficiency of performed surveys and treatment of the well bore zone of the formation with a combined water-jet effect on perforated openings or filters of the production casing and the pulse-cavitating flow to the formation structure with fluid and monitoring of the treatment parameters.

2 cl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method of acid treatment of bottom-hole zone of carbonate reservoir includes injection of the acid composition containing in wt %: inorganic or organic acid, or their mixture 9.0-24.0; zwitterion surface-active substance - oleinamidopropylbetaine 1.0-10.0; hydrophobically-modified polyurethane polymer 0.05-3.0; water - rest, at that the acid composition is injected by single stage or by portions with holding between injections. The acid composition can additionally contain anionic surface-active substance in amount of 0.1-3.0 wt %. The above specified acid composition is injected alternating with injection of hydrochloric acid at 12-24% concentration.

EFFECT: alignment of profile of inflow of the production wells in carbonate reservoirs with non-uniform permeability, creation of new fluid conducting channels through entire perforated thickness of the reservoir, restoration of reservoir characteristics of bottom-hole zone due to its cleaning of mud solid particles.

3 cl, 1 tbl, 16 ex, 4 dwg

FIELD: oil and gas industry.

SUBSTANCE: method of water production zone isolation in a well involves sequential injection of coagulation agent (25% solution of calcium chloride), buffer layer of fresh water, and Givpan acrylic reagent. Additionally, polyethylene terephthalate production waste product, PET with low polymerisation degree, is added to Givpan as a filler in amount of 18-24 wt %.

EFFECT: reduced core permeability.

1 dwg, 7 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: lubricating additive for drilling mud, characterised by it is prepared by mixing polyglycol, a floatation agent - oxal, isopropyl alcohol and tall oil at 50-60°C for 2 hours, adding a mixture of a fatty acid methyl ether and diethanolamide of coconut oil, then triethanolamine, raising the temperature to 75-80°C and mixing for 2 hours, adding copper or copper-calcium stearate and oxyethylated nonylphenol, mixing for 1 hour and adding a neutralising agent to pH not lower than 6.5, with the following ratio of components, wt %: polyglycol 27.3, isopropyl alcohol 9.1, floatation agent - oxal 24.3, tall oil 24.3, copper or copper-calcium stearate 3, triethanolamine 4.5-5, fatty acid methyl ether 1-1.5, diethanolamide of coconut oil 1, oxyethylated nonylphenol 3-4.5, neutralising agent 0.5-2.

EFFECT: low friction of drilling mud in metal-metal and metal-filter cake pairs, low pipe and casing wear rate when drilling extended-reach and ultra-extended-reach wells.

2 tbl, 2 ex

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil-extracting industry, in particular to methods of insulation of inflow of formation waters and lining of the bottomhole zone of formation, and also to the methods for adjustment of profile of acceleration performance of injection wells, to the methods for formation treatment, to the methods for regulation of development of oil fields, and can be used for elimination of leakage of production strings and creation of behind-the-casing filter, for elimination of behind-the-casing gas-manifestations, tubing-casing pressure and inter-formation overflows in behind-the-casing space of a well. The method of insulation of inflow of formation waters and lining of the bottomhole zone of formation includes injection of mix of siliceous substance with high-disperse hydrophobic material. Also the alkaline drain of ShchSPK caprolactam production is injected. The siliceous substance are organic-silicon oil-soluble and water-soluble substances or organic-silicon substances with the following ratio of components, wt %: organic-silicon oil-soluble and water-soluble substances or organic-silicon substances 44.9-77.0; high-disperse hydrophobic materials 0.1-3.0; alkaline drain of caprolactam production 20.0-55.0.

EFFECT: increase of insulation of inflow of waters and lining of the bottomhole zone, increase in the oil-sweeping ability of injected compositions possessing plastic properties unlike a prototype, necessary for more effective elimination of the problem of sand production, elimination of leakage from production strings and creation of the behind-the-casing filter.

7 cl, 4 tbl, 5 ex

FIELD: oil and gas industry.

SUBSTANCE: acid composition for treatment of bottom-hole zone of carbonate reservoir contains in wt %: inorganic or organic acid, or their mixtures 9.0-24.0; zwitterion surface-active substance - alkyl betaine 1.0-10.0; hydrophobically-modified urethane polymer 0.05-3.0; water - rest. The acid composition can additionally contain anionic surface-active substance in amount of 0.1-3.0 wt %.

EFFECT: alignment of injectivity profile of injection or inflow profile of the production wells in carbonate reservoirs with non-uniform permeability, creation of new fluid conducting channels through entire perforated thickness of the reservoir, restoration of reservoir characteristics of bottom-hole zone due to its cleaning of mud solid particles, increased thermal stability of injected acid composition.

2 cl, 1 tbl, 16 ex, 4 dwg

FIELD: oil and gas industry.

SUBSTANCE: dry mixture comprises a copolymer of acrylamide and acrylic acid - 71.4-83.3 wt %, paraformaldehyde - 10.0-17.8 wt % and resorcinol - 6.3-11.4 wt % or copolymer of acrylamide and acrylic acid - 69.5-82.5 wt %, paraformaldehyde - 9.5-17.7 wt %, resorcinol - 6.1-10.6 wt %, and aerosil - 0.9-3.0 wt %. The gelling composition is prepared by dissolving any of the said compounds in water. At that the gelling composition without aerosil can also be obtained by the introduction of paraformaldehyde in water immediately after the copolymer of acrylamide and acrylic acid, and resorcinol - after complete dissolution of the copolymer of acrylamide and acrylic acid. The resulting gelling composition comprises a copolymer of acrylamide and acrylic acid - 0.17-0.80 wt %, paraformaldehyde - 0.03-0.20 wt %, resorcinol - 0.02-0.12 wt %, water - the rest, or a copolymer of acrylamide and acrylic acid - 0.17-0.80 wt %, paraformaldehyde - 0.03-0.20 wt %, resorcinol - 0.02-0.12 wt %, aerosil - 0.01-0.03 wt %, water - the rest.

EFFECT: increasing the efficiency and manufacturability of the gelling composition by ensuring the solubility in water used for its preparation of the dry mixture, simplifying of preparation of the composition at high mechanical and thermal resistance.

3 cl, 3 tbl, 5 dwg, 8 ex

FIELD: oil and gas industry.

SUBSTANCE: group of inventions relates to inhibition of clay hydration during drilling and wells construction. Method of inhibition of clay hydration during drilling comprising use of water based mud containing from about 0.02 to about 5 wt % of bis-hexamethylenetetramine, salts of bis-hexamethylenetetramine or their mixtures as hydration inhibitor.

EFFECT: effective inhibition of clay hydration, stable inhibitor at ambient temperature, expansion of raw materials base due to wastes.

10 cl, 1 tbl, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to liquids for the hydraulic fracturing of subterranean formations in oil and gas extraction. The method of applying liquid for hydraulic fracturing in the formation of fracturing of subterranean formations includes the retardation of polymer splitting in the liquid for hydraulic fracturing at a temperature from 125 to 400°F, when the liquid for hydraulic fracturing contains a liquefier, by the combination of at least one radical acceptor with the liquid for hydraulic fracturing. The mixture for the application in the liquid for hydraulic fracturing contains a radical acceptor and a liquefier. The method of the hydraulic fracturing of subterranean formation includes the supply of the liquid for hydraulic fracturing, containing a propping means, a polymer and the liquefier, addition of the radical acceptor, supply of the liquid to a desired location in a subterranean formation to form at least one hydraulic fracturing, making it possible for the liquefier to split the polymer and reduce the viscosity of the liquid for hydraulic fracturing at a specified time or at a specified temperature. The invention is developed in dependent claims.

EFFECT: increase of viscosity control efficiency.

15 cl, 1 dwg, 1 ex

FIELD: mining.

SUBSTANCE: plugging material comprises portland cement, microdispersed and expansion additives, fluid loss additive, the setting accelerator and water. The composition comprises the microdispersed and expansion additives as microdispersed cement complex MDCC consisting of: micro-cement or silica, or metakaolin and calcium hydrosulphoaluminate in a weight ratio of 2:1, respectively; the fluid loss additive - as water binding complex WBC consisting of a copolymer vinyl acetate and ethylene with vinyl acetate groups content of 18-20%, hydroxyethyl cellulose and modified organosilicon reagent in a weight ratio of 10:1:0.5, respectively; and the composition comprises the setting accelerator as calcium chloride or sodium chloride, in the following ratio of components, parts by weight: portland cement: 75-95; MDCC 5-25; WBC 2.0-3.5; the said setting accelerator 0.1-3.0; water 47-60.

EFFECT: increase in adhesion, strength characteristics, reduction of filtrate return and dynamic shear stress, improvement of indices of water and gas-blocking properties of the plugging material and formed cement stone.

2 tbl

FIELD: mining.

SUBSTANCE: insulating composition for protection from intensive absorption in the intervals of fissured rocks, comprising cement foam material CFM of grades A, B, C and D, water and setting accelerator, characterised in that the composition additionally comprises a plasticiser and a foam stabiliser, at that it comprises the setting accelerator as a mixture of potassium chloride and sodium carbonate in a weight ratio of 1:1, respectively, the foam stabiliser - as a mixture of low molecular weight hydroxyethyl cellulose and ethoxylated nonylphenol with 9 carbon atoms in the alkyl radical and 12 moles of ethylene oxide, attached to a mole of alkyl phenol, in a weight ratio of 0.4:1, respectively, and the plasticiser - as high-molecular anionic surfactant sodium polycarboxylate in the following ratio of components, mass parts: CFM - 100.0; the said setting accelerator - 8.0-12.0; the said foam stabiliser - 0.5-0.7; the said plasticiser - 0.5-0.9; water - 50.0-60.0.

EFFECT: increase in the insulating properties in elimination of absorption by reducing the setting time, increase in the strength and adhesion properties, increase in resistance to erosion.

2 tbl

FIELD: production and exploratory well drilling, particularly foaming drilling fluids used during penetration through incompetent rock intervals and during primary productive oil and gas deposit opening in the case of abnormally low formation pressure.

SUBSTANCE: foam composition comprises surfactant, foam stabilizer, water, water hardness control additive and lubricant. The water hardness control additive is sodium silicate. The lubricant is VNIINP-117 emulsion. The foam stabilizer is polyacrylamide, the surfactant is sulphonole. All above components are taken in the following amounts (% by weight): sulphonole - 0.8-1.5, sodium silicate - 0.2-0.5, polyacrylamide - 0.1-0.5, VNIINP-117 - 0.5-2, remainder is water.

EFFECT: reduced power inputs for well drilling, as well as reduced coefficient of friction between drilling tool and well wall.

1 tbl

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