Method for processing underground productive beds. RU patent 2249097.

FIELD: oil and gas industry.

SUBSTANCE: method includes injection of processing liquid into bed, which liquid contains solved or dispersed in water complicated ether and polymer destructor, selected from oxidizing destructor and ferment destructor in such a way, that complicated ether is hydrolyzed with production of organic acid for solution of material soluble in acid, present in filtering layer or adjacent to it or in other damage in productive bed, and polymer destructor destroys polymer material, present in filtering layer or bio-film in productive bed.

EFFECT: higher efficiency, simplified method, higher productiveness, higher ecological safety.

31 cl, 1 tbl, 1 ex

IPC classes for russian patent Method for processing underground productive beds. RU patent 2249097. (RU 2249097):

E21B43/27 - by use of eroding chemicals, e.g. acids

E21B37/06 - using chemical means for preventing or limiting the deposition of paraffins or like substances (chemical compositions therefor C09K0008520000)

Another patents in same IPC classes:

Method for acidic treatment of productive bed / 2247833
Method includes serial pumping of film-forming hydrocarbon liquid and hydrochloric acid with adding of salt-acidic corrosion inhibitor to these, as said inhibitor a special paraffin deposits inhibitor is used, in form of composition of surfactants and aromatic solvents, while hydrochloric acid with addition of inhibitor before pumping is dispersed with gas to receive foam.

Method for range-wise treatment of productive layer through open horizontal well shaft and device for realization of said method / 2247832
Method includes determining porosity, penetrability and oil saturation level of shaft-adjacent area along whole length of deflected shaft. On basis of these ranges with low penetrability are detected, caverns presence level and diameters of shaft on ends thereof are determined. With consideration of characteristics of detected ranges at surface a pipe assembly is assembled, at end of which a ring saddle is mounted for locking ball, on both ends - hydraulic packers. Between these in assembly pipe a radial through calibrated channel is made. Pipe assembly is fixed at end of pipes column and these are lowered into chamber to level of deflected shaft mouth. With unpacked packers straight and backward washing of shaft is performed. After that acid is pumped into well in amount, equal to amount of first treatment range. Locking ball is dropped, first from the face shaft range with low penetrability is packed and concurrently acid is pressed therein, after that well is left for reaction. Then both packers are unpacked, backward washing of shaft is performed. By raising pipe column, pipe assembly with packers is transferred in backward, from face, direction into area of second, from face, range with low penetrability and above-mentioned operations are repeated. In turns, operations with each treatment range are performed.

Oil extraction methods / 2247235
Method includes treatment of face area of oil bed by hydrophobic powder in organic and pushing oil away from collector with following delivery of oil from face-adjacent area of extraction well for processing of oil-containing terrigenic bed into organic solvent additionally inserted is copolymer of ethylene with vinylacetate, well treatment is performed with relation of components in percents of mass: said powder 0.05-2, said copolymer 0,05-2, organic solvent - the rest.

Method for increasing productiveness of oil and gas wells / 2247234
Method includes acidic treatment of bed, calculation of hardness decrease and pressure of rocks tearing and pressure for pressing working solution into bed, completion of well and the actual hydraulic tear. Pressure for pressing is determined from formula Pht=(2μ·Pm/(1-μ)+(1-3μ)·Pb/(1-μ), where Pht - rocks tear pressure, Pm - mountain pressure, Pb - bed pressure, μ - Poisson coefficient.

Composition for declaying of bottom-hole formation zone / 2246612
Declaying composition contains clay dispersing reagent, peroxide compound and water, wherein as peroxide compound potassium fluoride peroxysolvate in activated form, comprising 1-3 mass % of oxalic or salicylic acid; and includes two sequential technological solutions. More specifically claimed composition contains (mass %): technological solutions 1: potassium fluoride peroxysolvate 1-2.5; hydrochloric acid as clay dispersing reagent 3-8.0; and balance: water; technological solutions 2: potassium fluoride peroxysolvate 1-2.5; sodium hydroxide as clay dispersing reagent 4-6.0; and balance: water. In addition said solution contain 0.1-1.0 mass % of water soluble surfactant. After treatment with disclosed solutions and well exposure dispersed reaction products are removed from bottom-hole formation zone.

Acid composition for treating terrigenous oil reservoirs and a method for acid treatment of bottom area of formation / 2244816
Invention provides composition that can be used to intensify oil inflow and to develop well by means of acid treatment of terrigenous oil reservoir as well as to intensify oil inflow and to increase oil recovery of formations with the aid of hydraulic rupture of formation assisted by acid solutions. Composition contains borohydrofluoric acid needed to create borosilicate films prohibiting migration of particles during acid treatment. In addition, composition is characterized by lowered rate of reaction with rock at formation temperature in order to extend coverage of formation by treatment and to diminish deposit formation risk, low surface tension, low corrosion rate, and compatibility with inhibitors added to commercial acid, which will enhance efficiency of acid treatment using composition of invention. Composition is made up of, wt %: inhibited hydrochloric acid 8.0-15.0, fluorine-containing reagent (hydrofluoric acid, ammonium bifluoride, or ammonium fluoride) 1.5-10.0, boric acid 1.0-3.0, additionally isopropyl alcohol 5.0-10.0, and "Alkylfosfat-Khimeko" or "Efiroks-7", or "Fosfol-10" 0.5-2.0, and fresh water to 100%. In a method of acid treatment of the bottom area of terrigenous formation comprising consecutively pumping flushing fluid and acid composition into borehole, forcing the latter into formation by the aid of flushing fluid, giving time (up to 8 h) for reaction and subsequent removal of reaction products. Acid composition is used as it is or in the form of aqueous solution obtained by diluting composition with fresh water at water-to-composition ratio (1-5):1 in amount corresponding to 0.5-2.0 m3 per 1 m of perforated thickness of the formation. As flushing fluid, 1.5-3.0% ammonium chloride solution is used in amount 0.5-1.5 m3/m before pumping of acid composition or in amount 1.0-5.0 m3/m when used to force acid composition.

Composition for treating bottom zones of wells / 2244114
Invention relates to compositions used for intensifying wells owing to increasing permeability of rocks forming well bottom zones. Composition of invention contains 7.0 to 30.0% ethanol, 0.1 to 0.3% cupric chloride, 0.1 to 0.5% alkylbenzenesulfonate, and trichloroacetic acid (to 100%).

Device for treating well walls within range of productive bed / 2244112
Device has pipe-like body with detachable upper and lower sleeves. Concentrically to body, with possible rotation relatively to it, a cover is mounted with blades with scrapers placed spirally on its surface. To lower sleeve a reactive end piece is connected with slit apertures. End piece hollow is filled with granulated material engaging in exothermal reaction with acid. Lower portion of end piece is provided with check valve. Upper sleeve is provided with check valve having locking element in form of sphere with shelf and centering elements, to be dropped from well mouth. Base of saddle of check valve is made in form of disc having diameter equal to diameter of body. Pass aperture of saddle in lower portion is overlapped with easily destructible and easily removed element. Length of sphere shelf is greater than height of pass aperture of saddle of check valve of upper sleeve.

Method of treating bottom zone of low-permeable oil reservoirs / 2244111
Invention aims at increasing productivity of oil- and gas-producing and injecting wells exposing high-temperature low-permeable oil reservoirs. In the treatment method according to invention including forcing enzyme substrate and separate enzyme into formation and creating conditions to enzymatically convert substrate into acid, geologic and productive characteristics for each interval of bottom zone are determined in order to pick out low-permeable intervals of oil reservoir for treatment, whereupon properties of enzyme substrate and separate enzyme as well as conditions for their pumping are chosen. Substrate utilized in the method is head fraction of methyl- and/or ethyl-, and/or butyl acetate production, to which aliphatic alcohols are added, and enzyme is an acid solution. Substrate is pumped simultaneously and/or before, and/or after pumping of enzyme, after which well is closed for some time and then opened and placed under predetermined operational conditions.

Method for operation of gas-condensate deposit / 2245997
Method includes examination of operation well for gas-condensation and periodical cleaning of face-adjacent well area from precipitating hydrocarbon condensate by pumping hydrocarbon condensate solvent into bed, exposure of well for period of condensate dissolution and following removal of received solution from face-adjacent area during well launch, as solvent binary mixture is used with unlimited mutual solubility of components, while at least one of them has unlimited mutual solubility with hydrocarbon condensate, and relation of binary mixture components is determined from previously built phase diagram of three-component system, formed during dissolution of hydrocarbon condensate. As binary mixture with unlimited mutual solubility of components a mixture of acetone and methanol is used, or chloroform and methanol, or chloroform and aniline, or chloroform and acetone.

Hard compound for preventing sedimentations of non-organic salts and ferrum sulfide during extraction and transportation of oil / 2244805
Compound includes organic acidic reagent and cubic remains of amine production C17-C20, and as organic acidic reagent contains sulphamine acid with following ratio of components in percents of mass: sulphamine acid 20-70, C17-C20 the rest or mixture of sulphamine acid with nitriletetramethylphosphone acid with following ratio of components in percents of mass: sulphamine acid 10-40, nitriletetramethylphosphone acid 25-70, C17-C20 the rest.

Composition for removing asphaltene-tar-paraffin deposits manifesting oil-field equipment corrosion inhibitory effect / 2244101
Composition according to invention, which can be used for asphaltene-tar-paraffin deposits from bottom zone of formation, discharge pipes, oil-collection reservoirs, and oil-field equipment, contains 1-5 vol % nonionic surfactant: oleic acid, С9-С12-alkyl-phenol, С9-С10-alkyl-phenol, or N-alkyl-3-methyl-5-ethylpyridinum bromide in solvent; 1-5% cationic surfactant: product of reaction of primary and secondary aliphatic amine mixture with industrial-grade dimethyl phosphite; and solvent (Absorbent A) in balancing amount. Composition can also be based on straight-run gasoline containing in this case 10 to 50 vol % Absorbent A.

Paraffin deposit-preventing hydrophilic property imparting composition / 2244100
Invention is intended to protect inner surface of transmission pipelines against asphalt-tar-paraffin deposits and provides appropriate composition containing 0.5-10% polyvinyl alcohol, 0.01-1% nonionic surfactant (FK 2000 PLUS), and water.

Method for processing underground productive beds / 2249097
Method includes injection of processing liquid into bed, which liquid contains solved or dispersed in water complicated ether and polymer destructor, selected from oxidizing destructor and ferment destructor in such a way, that complicated ether is hydrolyzed with production of organic acid for solution of material soluble in acid, present in filtering layer or adjacent to it or in other damage in productive bed, and polymer destructor destroys polymer material, present in filtering layer or bio-film in productive bed.

Compound for removal of asphalt-resin-paraffin precipitations and hydrophobization of face-adjacent bed zone / 2249673
Compound has processed cyclohexane fraction, processed tallic or rapeseed oil, additionally has modified high-dispersion polysyl-grade silica with following ratio of components in percents of mass: processed cyclohexane fraction 69.9-78.0, processed tallic or rapeseed oil 20.0-30.0, polysyl 0.1-2.0.

Composition for inhibition of asphalt-resin-paraffin precipitations / 2249674
Composition for prevention of asphalt-resin-paraffin precipitations on basis of liquid pyrolysis products, used in amount of 0.03-0.05 of oil mass, has following composition, %: dark oil polymer resin, received by oxidizing polymerization of heavy pyrolysis resin during blowing of air with flow 17-23 hour-1, temperature 145-155°C in presence of cobalt salts during 2-2.5 hours, 30-35, alkylaromatic hydrocarbons 65-70.

Gas well thawing method / 2254447
Method involves lowering flushing pipe string of lesser diameter into producing tube; flushing well bore with hot technological solution and lengthening flushing pipes as hydrate ice block damages, wherein potassium chloride electrolyte is used as the technological solution.