Method of increasing oil production and reduction of water cutting of production

FIELD: oil and gas industry.

SUBSTANCE: invention relates to methods of increasing oil production and reducing water cutting of production. According to the method water with initial ionic force of 0.0004-0.0008 mole/l is activated in a cathode zone of diaphragm electrolytic cell chamber during 0.5-3 hrs at imposition onto water of electric field of E=(1000-15000) V/m strength. Powder of silica sand, or glauconite, or a rank of alumina silicates: zeolite or amphoteric materials: bentonite, montmorillonite, nontronite, kaoline (anauxite), talk, pyrophyllite, each separately or in random mixture are introduced into activated water at weight ratio to water 5-25%. Produced dispersive mixture is passed through the cathode zone of the electrolytic cell at strength of electric field E=(1000-15000) V/m at a rate of 1-10 m3/hour during one hour, thus obtaining activated dispersive system which further is pumped into horizon in volume of 5-100 m3. After that fresh water is pumped into the horizon as a buffer at volume of 1-20 and 3-80 m3 of horizon water as driving under pressure of 60-90 atm at during 3-5 hours.

EFFECT: increased yield of oil from layer-by layer non uniform horizons, reduced volume of pumped off produced mineralised water, reduced ecological danger of fresh water mineralisation in open water reservoirs, bogging of soil and formation of alkaline lands on it.

2 ex

 

The invention relates to methods of increasing oil production and reduce the water content of the produced products, especially from layer-by-layer heterogeneous reservoirs in the development of oil fields.

A significant place among physico-chemical methods of enhanced oil recovery methods take using vodoulaviteli materials [see Tupikov I.Z., Makarov D., Krupin SV and other Method of increasing oil production from the reservoir and reduce the water content of products produced by the subject injection aktivirovannoi dispersed system. The technology of oil and gas. Kazan state technological University, Kazan, No. 1, 2005, p.30-32]. On the fields of the Russian Federation, in particular the Ulyanovsk region, Tatarstan, to solve EOR layer-by-layer heterogeneous reservoirs and reduce the number of associated wastewater pumped widespread use of polymer-dispersed systems, representing clay dispersion with the addition of polyacrylamide, which showed high efficiency in various mining and geological conditions of development of oil fields.

However, a sharp increase in the size of clay particles when flocculation caused by polyacrylamide that can cause irreversible clogging of the pores of the reservoir rock with the corresponding irreversible consequences: reducing the prop is knymi water capacity in cross sections of the formation.

The closest to the number of matching characteristics and the maximum achievable positive effect is a method of increasing oil production from the reservoir and reduce the water content of products produced by the method of injection of activated dispersive systems [see Tupikov I.Z., Makarov D., Krupin SV and other Method of increasing oil production from the reservoir and reduce the water content of products produced by the subject injection activated dispersive system (ADS). The technology of oil and gas. Kazan state technological University, Kazan, No. 1, 2005, p.30-32], namely, that the water with the ionic strength of 0.0004-0,0008 mol/l activate the camera diaphragm electrolyzer, drained activated water into the tank, is introduced into the water tank powder bentonite clay mass ratio of water 5-25%, thereby getting the BPA, which pump displacement of 5.5 m3into the reservoir, then the BPA forced into the reservoir with fresh water volume of 1 m3as the buffer reservoir water quality produce under the pressure of 60-90 psi for 3-5 hours. The technical effect of the prototype method is to increase oil production 6 times, reducing the water content of the oil from 90 to 65%.

The disadvantage of the prototype is the lack of increase of oil recovery, insufficient largest decrease in water content of produced fluids.

The technical is a mere result of the proposed method is to increase oil recovery in layers heterogeneous formations 10-100 times, reducing the number of pumped associated mineralized waters, i.e. reducing the water content of the oil from 90% to 40% with a corresponding decrease in environmental salinity hazard freshwater open water, waterlogged soils, saline soils formed on them.

This technical result is achieved by the fact that the diaphragm electrolyzer activate for 0.5-3 hours in the water with the initial ionic strength of 0.0004-0,0008 mol/l after application of an electric field of strength E=(1000-15000)/m, then the activated water is injected powder quartz sand, or glauconite green sand - silicate with continuous layers of tetrahedra SiO4), or from a number of silicates: zeolites, or amphoteric materials: bentonite, montmorillonite, beidellite, nontronite, kaolinite (anoxia), talc, pyrophyllite, individually or in arbitrary mixtures thereof in a weight ratio of water 5-25%, obtaining a dispersion mixture miss the obtained dispersion mixture through a zone of the cell when the electric field strength value E=(1000-15000)/m with a speed of 1-10 m3per hour for one hour, get thereby activated dispersive system (ADS), download the BPA displacement of 5-100 m3the reservoir is then pumped into the reservoir of fresh water as a buffer in an amount of 1-20 m3, download 3-80 m3p is astool water as produce under the pressure of 60-90 psi for 3-5 hours.

Specified in the claims the parameter ranges vary based on the following considerations, within the following limits: regardless of the initial ionic strength of the water during its activation when applying to the electrodes a diaphragm electrolyzer low voltage 1000 V/m activation time is 3 hours, after application of the maximum voltage 15000/m - 0.5 hours; if the activation of the dispersion mixture is carried out at the lower limit of the mass ratio of 5 wt.% powders of quartz sand or glauconite, or number of aluminosilicates of the zeolite or amphoteric materials activated with water, then apply the maximum value of the electric field strength E=15000/m and the minimum speed of the dispersion mixture through a cation area cell 1 DOE per hour; with an upper limit corresponding to a mass ratio of 25% is used the minimum value of the electric field E=1000 V/m at the maximum value of the propagation velocity dispersion of the mixture through a cation area of the electrolyzer 10 m3/hour. When the injection of the BPA with the volume of 5 m3this layer is then pumped fresh water as a buffer in the amount of 1 m3, produced water in the amount of 3 m3at a pressure of 60 psi for 5 hours, when the injection BPA displacement of 100 m3this PLA is t then pumped fresh water as a buffer in the amount of 1 m 3, produced water in the amount of 3 m3at a pressure of 60 ATM.

Example 1. Water with ionic strength 0,0007 mol/l activate within 3 hours after application of it in cationic zone of the diaphragm electrolyzer voltage 1000 V/m, is introduced into the activated water 5 wt.% powder montmorillonite, get thereby dispersing the mixture, let the obtained dispersion mixture through the cathode zone of the cell during the hours when the electric field strength value E=1000 V/m at 1 m3per hour, get activated dispersion mixture, inject activated dispersing the mixture by volume of 5 m3in the reservoir, the wells of which were in intermittent operation with a monthly production of 2 t with a water content of 90%, is then pumped into the reservoir of fresh water as a buffer in the amount of 1 m3, download 3.5 m3produced water as produce under pressure of 60 psi for 5 hours.

After downloading the BPA bore of the intermittent operation moved into permanent, monthly production was increased from 2 to 40 tons, after two months, the water content decreased from 90% to 50%, the monthly oil production increased to 150 tons with a corresponding decrease in environmental salinity hazard freshwater open water, waterlogged soils, saline soils formed on them.

Example 2. Water with ionic strength 0,0005 the ol/l trigger for 0.5 hours at imposing on her cationic zone of the diaphragm electrolyzer voltage 15000/m, introducing the activated water 25 wt.% the zeolite powder, receive thereby dispersing the mixture, let the obtained dispersion mixture through the cathode zone of the cell during the hours when the electric field strength value E=15000/m with a speed of 10 m3per hour, get activated dispersion mixture, inject activated dispersing the mixture with a volume of 75 m3in the reservoir, the wells of which were in intermittent operation with a monthly output of 30 tons with a water content of 91%, is then pumped into the reservoir of fresh water as a buffer of 15 m3, download 55 m3produced water as produce under pressure 90 psi for 5 hours.

After downloading the BPA bore of the intermittent operation moved into permanent, monthly production was increased from 30 to 450 tons, after two months, the water content decreased from 91% to 45%, the monthly oil production has increased up to 1500 tons, with a corresponding decrease environmental hazards salinity of fresh water open water, waterlogged soils, saline soils formed on them.

Thus, the presented data demonstrate the implementation of the use of the claimed invention the following cumulative conditions:

the tool embodying the claimed method in its implementation, is intended for use in producing the th industry, namely, to increase oil production from the reservoir and reduce the water content of the produced products, especially from layer-by-layer heterogeneous reservoirs in the oil field development;

for the inventive method, it is described in the independent clause sets out the claims, confirmed the possibility of its implementation using the steps described in the application or known before the priority date tools and methods.

Therefore, the claimed invention meets the condition of "industrial applicability".

The way to increase oil production and reduce the water content of the produced products, especially from layer-by-layer heterogeneous reservoirs in the development of oil fields, including the activation of the cathode zone of the camera diaphragm electrolytic cell for 0.5-3 h water source ionic strength of 0.0004-0,0008 mol/l after application of an electric field of strength E=(1000-15 000)/m, introduction into the water of the powder material in a mass ratio of water 5-25%, i.e. obtaining the dispersion mixture, characterized in that the activated water is injected powder quartz sand, or glauconite (green sand, silicate with continuous layers of tetrahedra SiO4), or the number of silicates: zeolite or amphoteric materials: bentonite, montmorillonite, beidellite, nontronite, kaolinite (anoxia), talc, pyrophyllite, individually or in arbitrary mixtures thereof in a weight ratio of water from 5-25%, obtaining a dispersion mixture miss the obtained dispersion mixture through a zone of the cell when the electric field strength value E=(1000-15000)/m with a speed of 1-10 m3/h for one hour, get thereby activated dispersion mixture ADS, download the BPA displacement of 5-100 m3the reservoir is then pumped into the reservoir of fresh water as a buffer in an amount of 1-20 m3, download 3-80 m3produced water as produce under the pressure of 60-90 psi for 3-5 hours



 

Same patents:

FIELD: petroleum industry.

SUBSTANCE: invention relates to oil and gas production industry, namely to dry operation of wells. The substance of the invention is as follows: according to this method wells are equipped with flow and production strings and includes injection of water repellent compound under pressure into the seam. According the invention prior to mining operations a flexible pipe is lowered into the internal space of the production string under pressure by means of the coil tubing rig. The circular and annular spaces of the well are opened. The water repellent compound is injected through the flexible pipe in the amount required, overpressure being maintained in the circular and annular spaces, which exceeds the pressure of the water repellent compound injected by not less than 10%. The water repellent compound is forced through into the seam up to the depth required. Next the flexible pipe is withdrawn out of the well. The water repellent compound is injected regularly during the period of increased gas extraction out of wells without killing the same.

EFFECT: possibility of long-term dry operation of wells with maintaining initial effective thickness of the seam.

3 cl, 1 ex, 3 dwg

FIELD: oil industry, particularly non-uniform reservoir development.

SUBSTANCE: method involves injecting isolation composition namely Portland cement dispersion and water-soluble polymer in well, wherein the components are taken in proportion of 1:(0.01-0.5) in oil-bitumen product, 5-56 parts by weight of Portland cement and water-soluble polymer are taken for 100 parts by volume of said dispersion; injecting aqueous Portland cement solution along with said dispersion, wherein the solution is taken in proportion of (0.1-0.5) per 1 part of said dispersion.

EFFECT: increased efficiency of stacked oil pool development and highly-permeable watered reservoir zones isolation.

2 cl, 3 tbl, 3 ex

FIELD: underground well repair, particularly methods to create behind-casing screen in productive reservoir of oil, water and gas wells.

SUBSTANCE: method involves injecting foamed polymeric solution including water-soluble polymer in amount of 1.5-2.5 % by weight, foaming agent in amount of 1-3% by weight, cross-linking foam stabilizing agent in amount of 0.2-0.6% by weight and water in bottomhole formation zone; injecting porous plugging composition including cement grout with 0.3-0.5 water-cement rate taken in amount of 60-80% by weight, above mentioned foamed polymeric solution in amount of 20-40% by weight in bottomhole formation zone. Each of said solutions is characterized by viscosity η and yield point τ change during injection and cross-linkage thereof.

EFFECT: prevention of bottomhole formation zone blocking in slightly cemented reservoirs.

8 cl, 4 tbl, 5 dwg, 1 ex

FIELD: oil production, particularly by reservoir waterflooding.

SUBSTANCE: method involves cyclically injecting polymeric dispersed system components in reservoir, wherein the polymeric dispersed system includes polyacrylamide, mud powder, chromium composition and water. The mud powder is modified bentonite mud powder. The polymeric dispersed system is injected in the following way. First of all 4-6% modified bentonite mud powder suspension in 0.04-0.12% aqueous polyacrylamide solution is injected in well. Then the suspension is forced in reservoir with buffer water volume and holding in reservoir within 1-3 hours. After that 1-6% modified bentonite mud powder suspension in water including 0.005-0.015% of chromium composition is injected in well under pressure 10-40% higher than water injection pressure in series with mixture including 0.07-0.25% aqueous polyacrylamide solution and 0.033-0.1% chromium composition solution under water injection pressure.

EFFECT: increased oil recovery from reservoirs, decreased water content in produced product and prevention of reservoir bottom area mudding.

2 ex

FIELD: oil production, particularly preventing gas- or water-coning phenomena, for instance the formation of a conical column of gas or water around wells.

SUBSTANCE: method involves injecting hydrophobic composition in water influx channels; lowering and installing shutter provided with shoe at shutter end within water influx interval. The shoe may slide upwards in axial direction and is retained with shear members. The shoe has longitudinal and side communicating channels. Before hydrophobic composition injection the shutter is lowered to well bottom without supporting thereof. After that low-diameter pipe string is additionally inserted in shutter to provide airtight cooperation thereof with longitudinal channel. After hydrophobic composition injection through side channels the shutter is lowered to well bottom up to upward shoe movement with side channel closing. Low-diameter pipe string is removed from well before shutter installation.

EFFECT: improved water influx isolation.

1 dwg

FIELD: oil and gas industry, particularly temporary plugging of productive reservoir intervals, killing of wells having abnormally low reservoir pressure during well repair and to separate gas and oil intervals during plugging of multizone reservoir under combined development thereof and lost-circulation zone isolation during well drilling.

SUBSTANCE: method involves creating porous packer by injection of two compositions, namely polymeric solution and plugging liquid in well, wherein polymeric composition includes water-soluble polymer, cross-linking agent, foaming agent and water. The water-soluble polymer is polyacrylamide and/or carboxymethylcellulose and/or styromaleate. Above components are taken in the following amounts (% by weight): water-soluble polymer - 0.1-10, cross-linking agent, namely Cr2(SO4)3, Cr(C2H3O2)3, CrCl3, - 0.05-10, foaming agent, namely sodium alkyl benzene sulfonate, Neonol, sulfanole, Neftenol, - 0.1-5.0, remainder is water. The composition may additionally have gaseous agent, namely nitrogen, carbon dioxide, natural gas so that expansion ratio of the composition is 1.28-3.0. The plugging liquid is invert emulsion based on hydrocarbon phase, namely oil and/or hydrocarbon solvent, aqueous phase, namely water and/or salt solution of CaCl2 or NaCl2 or MgCl2 or BaCl2 in emulsifier presence. Above components are taken in the following amounts (% by weight) - hydrocarbon phase 15-18, aqueous phase - 72-82, emulsifier is 3-10. The composition is serially injected in well and followed by well killing liquid injection. Extreme dynamic shearing stress of polymeric solution is 25-110 Pa. Static shearing stress of porous packer is 50-410 Pa. Composition is formed on surface with cementing agent usage. The compositions are injected in laminar flow regime. Packer porosity is 10-50%. Plugging liquid volume is 2-4 m3, density thereof exceeds that of well killing liquid. The injection is carried out in two stages and time interval between the stages is not less than 30 min. Injection pressure is not higher than proof-test pressure. In winter unfreezing liquid is added to polymeric composition. Packer density is changed by heaving agent, namely metal salt CaCl2, KCl, MgCl2, BaCl2 solution addition. Packer is also used to create elastico-viscous screen to protect against mechanical impurities entering from exploitable reservoir or to isolate reservoirs during simultaneous or serial reservoir exploitation. Packer is retained for predetermined time interval.

EFFECT: possibility to maintain collecting properties of reservoir during current well repair and well workover.

20 cl, 5 ex, 3 tbl

FIELD: oil and gas production industry, particularly to treat bottomhole formation zone during oil and gas production.

SUBSTANCE: method involves inserting material for further exothermal reaction performing in well; forcing hydrochloric acid through the material and executing time delay. The material used for exothermal reaction performing is in the form of aluminum cuttings. First of all aqueous carboxymethylcellulose solution is formed. Then calculated amount of aluminum cuttings and grinded raw rubber are added to the solution. Above components are taken in the following amounts (% by weight): carboxymethylcellulose - 1.5, aluminum cuttings - 14.5, raw rubber - 11.6, water - 72.4. After that the ready solution is forced in reservoir and 20% hydrochloric acid is injected in well. Ratio between aluminum and hydrochloric acid is 25.0 parts by weight of aluminum per 75.0 parts by weight of hydrochloric acid.

EFFECT: increased bottomhole formation zone treatment reliability.

1 tbl

FIELD: oil and gas production.

SUBSTANCE: whole process comprises primarily exposing well on polymer-chalk mortar, perforating bottom zone of formation under polymer-chalk mortar layer, creating acid-degradable protective shield in bottom zone by forcing polymer-chalk mortar under pressure exceeding specified cementation pressure by 10-15%. Thereafter, casing string is descended, annular space is cemented, and bottom zone of formation is re-perforated through casing string and protective layer is destroyed with acid. Polymer-chalk mortar has following composition, wt %: soda ash 1-6, carboxymethylcellulose 1-6, polyacrylamide 2-3, clay 48-52, chalk 46-50, water - the balance.

EFFECT: increased productivity of formation due to prevented negative action of drilling fluids and appearance of softened bottom zone.

FIELD: oil production industry, particularly methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells.

SUBSTANCE: method involves lowering casing pipe string in well, wherein the casing pipe string is provided with channels located in water-bearing productive reservoir section; cementing hole annuity; isolating water-bearing section of productive reservoir by injecting water-proofing composition via casing pipe string channels; closing the channels with gate and exposing oil-bearing productive reservoir section for the second time. Before casing pipe string lowering in well hollow rigid centrators are formed in the channels. The centrators and the channels are filled with bitumen and closed with gate. Before water-proofing composition injection in water-bearing productive reservoir section the gate is opened. The water-proofing composition is non-hardening water-proofing composition. Then hollow rigid centrators and channels are freed of bitumen and cement stone is broken within the interval of water-bearing productive reservoir section by implosion action application thereto.

EFFECT: increased efficiency and decreased labor inputs.

2 cl, 1 dwg

FIELD: petroleum industry; natural gas industry; methods of isolation of the productive strata overlapped by the casing strings and the grouting mortar for its realization at the productive strata overhaul repair.

SUBSTANCE: the invention is pertaining to petroleum industry and natural gas industry, in particular, to the productive strata overhaul repair conducted in the process of the fields operation and at elimination of the development wells, which have fulfilled their assignment. The method may find the greatest application at operation of the multi-layer oil-fields and at elimination of the wells of the complex construction, specially on the final stage of the realized works - in the direct proximity to the earth surface for protection, for example, of the potable water, brackish waters and of the permafrost area, where their boreholes are socket by 3-4 and more casing strings. The technical result of the invention is extension of the technological possibilities of the method at the increased efficiency of the isolationof the productive strata. The grouting mortar for isolation of the productive strata overlapped by the casing strings, including Microdur-261R-X and the water, additionally contains calcium chloride, aluminum sulfate, nitriletrimethylenephosphonic acid NTF at the following ratio of the components (in mass %): Microdur-261R-X - 10-30, calcium chloride - 20-50, aluminum sulfate - 0.5-3.0, NTF - 0.0-0.2, water - the rest. The method of isolation of the productive strata overlapped by the casing strings including installation of the isolation cement bridges provides, that one of the isolation cement bridges is installed in the production string by 10-30 m below the interval of works, then using the hydroabrasive perforator cut slits in the casing strings - in the operational string and the intermediate strings - the vertical slits (3-5 slits per one meter), by means of the hydroabrasive cutter below and above the interval of the vertical slots cut all the casing strings forming the horizontal slits and the local cavities, in the formed vertical and horizontal slits and in the local cavities press through the above-mentioned grouting mortar with location of the roofing of the isolation bridge by 10-20 m above the interval of the works, then install the control isolation cement bridge, the base of which is placed on the roofing of the isolation bridge.

EFFECT: the invention ensures extension of the technological possibilities of the method at the increased efficiency of the isolationof the productive strata.

2 cl, 2 dwg, 1 tbl

FIELD: oil and gas industry.

SUBSTANCE: invention relates to development of non-uniform hydrocarbons deposit. The essence of the invention is as follows: according to the method a displacement agent is pumped into pressure wells and production is withdrawn from producing wells. On base of injection capacities of displacement agent and production watering parameters of wells operation are analyzed. Pressure wells with non-uniform capacity and producing wells with watering of production above the established level are chosen. There pumped into pressure wells water solution of "асидол-мылонафта", alternating solutions of "асидол-мылонафта" and water solutions of calcium chloride with consumption 0.3-0.6 m3 per 1 m of horizon thickness providing formation of a plastic sedimentation in this horizon at their interconnection in the horizon, preventing absorption of well and additionally of insulating material from not-reacted portions of the said water solutions at gas or horizon waters breaks-in. Further fringes of water solutions of alkaline drain of caprolactam production -ADC- of concentration not less 10% are pumped. At that pressure of pumping is raised by 2-5 atm at every 2-5 m3 of pumped components water solutions.

EFFECT: upgraded efficiency of method.

5 cl

FIELD: oil and gas industry.

SUBSTANCE: invention refers to oil industry, particularly to alteration of filter characteristics of non-uniform formations, to growth of oil withdrawal and to reduction of watering in producing wells with obtaining maximum effect at later stages of oil deposit development due to implementation of visco-elastic polymer compositions. According to the method of equalizing the intake capacity profile in pressure wells and limiting inflow into producing wells, including preparation and successive pumping into the formation of polymer gel-forming compositions, volume of pumping is preliminary determined, then 15% of porous volume of the first fringe of polymer composition is pumped, wt %: carboxymethyl cellulose - CMC - 0.3-5.0, cross-linker - chromium acetate - 0.05-0.5, water with mineralization - 0-290 g/l- the rest, where water with mineralization 50-290 g/l is used for preparation of cross-linker, then the second portion of the fringe is pumped in portions alternating with water pumping with surface active substance -SAS and the first fringe. The second fringe has the composition, wt %: polyacrylamide - PAA - 0.01-2.0, chromium acetate 0.05-0.5, water with mineralisation of 0-290 g/l - the rest. Then the well is stopped for process conditioning for 1-5 days. The invention is developed in dependent claims.

EFFECT: increased oil withdrawal of formation, reduced watering of producing wells, and expanded technological capabilities of method.

4 cl, 1 tbl

FIELD: oil and gas.

SUBSTANCE: invention may be used for the recovery of oil from wells with deep-well pumps. The method involves feeding oil treated with anti-seize agent to the pump suction. According to the invention, a loading dose of anti-seize agent is applied to the oil column in the annulus. Gradual influx of treated oil from the annulus to the pump suction is provided by natural pressure fluctuations in the well production gathering system. Based on the results of periodic deep-well pump dynamography, if required for one-time influx of treated oil, the casing valve on the wellhead is closed for a period of time sufficient for annulus pressure increase by 0.1-0.2 kgf/cm2.

EFFECT: protection of pump plunger pair against seizing.

2 cl, 3 tbl, 2 ex, 4 dwg

FIELD: chemistry.

SUBSTANCE: the invention pertains to an acidic phosphorous containing reagent, is used in the oil industry, heat energy, textile industry, production of mineral fertilizers and household chemistry, and to methods of obtaining the reagent. The reagent (conventional name "АФК-1") contains the following in given mass %: acetoxyethylidenediphosphonic acid 50.0-95.0 mass %, acetic acid - 29.5-0.5 mass %, the rest is acetic anhydride to 100. The quantitative composition of the indicated reagent is determined by the method of obtaining it and the ratios of the initial reagents. The method of obtaining the reagent involves adding acetic anhydride to a suspension of acetic and phosphorous acid at temperature of 60-90°C for a period of 1.5 hours. The reaction mixture is kept at 100-110°C for 1 hour and acidic impurities are distilled off to a controlled volume of distillate. Similar methods are developed based on phosphorous containing wastes from production of acid chlorides of higher fatty acids. The wastes are treated with water or a water solution of acetic acid with subsequent separation of the organic layer of fatty acids, after which the residue, containing phosphorous acid, is treated with phosphorous tri-chloride and acetic anhydride at 115-130°C, and acidic impurities are distilled off to the controlled distillate volume.

EFFECT: simplification of the process of obtaining acidic phosphorous containing reagent and increase in its ecological safety with reduction of the quantity of wastes.

4 cl, 17 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention pertains to the chemistry of phosphorous organic compounds, and specifically to an acidic phosphorous containing complex-forming reagent, which can be used in the oil industry, heat energy, textile industry, production of mineral fertilizers and household chemistry, and to the method of obtaining it. The acidic phosphorous containing complex-forming reagent (conventional name "АФК-2") contains the following in mass %: acetoxyethylidenediphosphonic acid - 50-95 mass %, acetic acid - 50-5 mass %. The method of obtaining the composition involves adding phosphorous tri-chloride, acetic acid and water simultaneously to glacial acetic acid in molar ratios equal to 1:(4.5-5.5):(1.93-1.95), at temperature of 35-45°C with subsequent keeping of the reaction mixture at 110-120°C for a period of 2 hours and controlled distillation of acidic impurities to the required distillate volume.

EFFECT: simplification of the process of obtaining phosphorous containing complex-forming reagent and increasing its ecological safety with reduction on the quantity of wastes.

2 cl, 15 ex, 2 tbl

FIELD: mining.

SUBSTANCE: invention can be applied in oil yield increase and well product watering reduction at the wells in a formation with variable permeability. The process of heterogenic oil-bearing formation development involves injection of dispersion of chemically obtained gel particles in water polymeric solution into the formation. A linear polymer is applied with the following component ratio, mass %: gel particles 0.17-1.0, linear polymer 0.25-1.8, water - the rest.

EFFECT: improved development efficiency due to higher dispersion permeability in the formation.

4 tbl, 1 ex, 6 dwg

FIELD: oil industry.

SUBSTANCE: at later stage of oil reservoir exploitation after high penetrating layers isolation repressuring bank medium of micellar solution, buffer liquid and additionally strained Cenomanian water are consistenly injected through intake well in less penetrating layers in cycle operation, micellar solution of mass.%: syntanol-ALM-10 - 0.5-22.0, polyalkylbenzol pitch with m.m. 120-220 - 4.0-31.0, strained Cenomanian water is the rest, buffer liquid contains polyacrylamid composition - 0.005-0.05% of water volume in it, bulk volume of bank micellar solution - 8.0-10.0%, buffer liquid 20.0-30.0% of void volume of the second layers group.

EFFECT: exploitation effectiveness improvement and productive rate of low penetrating layers group.

1 ex

Oil recovery method // 2327032

FIELD: oil industry.

SUBSTANCE: one pumps technologic water solution through key well in jointy-heterogenetic high flooded oil reservoirs, containing mas.%: colloidal silica with silica module 25-70 1.0-2.5, sodium soluble silicat with silica module 2.8-4.5 1.0-2.5, the rest is fresh water. Before and after pumping of technological solution buffer is pumped. After finishing of each cycle of technological solution and buffer pumping, mineralised water is pumped. Then one recovers oil through exploitation well.

EFFECT: oil recovery increasing from high flooded jointy-heterogenetic oil reservoirs.

4 tbl

FIELD: oil field development, particularly to increase oil recovery from flooded oil reservoirs with non-uniform permeability by control of injection well injectivity profile.

SUBSTANCE: method involves preparing silica gel; metering and mixing thereof with water to be injected from water conduit and injecting the obtained silica gel suspension in well. First of all initial injection well injectivity is determined. Silica gel is prepared by simultaneous mixing of dilute hydrochloric acid and sodium silicate solution jets in conveyer screw provided with variable speed drive, wherein the solutions are taken in proportion from 1:1 to 1:2. Rate of said solutions is regulated by change of variable speed drive index in dependence of solution concentration. Diluted solution concentrations and ratio thereof is carried out to provide rapid gel forming during component mixing. Silica gel is milled in conveyer screw to obtain gel particles of 0.01-0.5 mm dimensions. Gel is added to water to provide 0.05-75% by weight concentration. Injection is carried out in dependence of initial well injectivity beginning from minimal suspension concentration under minimal injection pressure with gradual concentration increase up to admissible value of pressure acting on production string with following pressure value maintenance due to suspension concentration reduction.

EFFECT: increased efficiency due to control of composition components mixing and regulation of silicate gel H-factor stability, increased gel suspension filtering ability index and extended functional capabilities of method realization.

1 ex, 4 tbl

FIELD: oil production, particularly microbiological and hydrodynamic methods for reservoir recovery increase.

SUBSTANCE: method to develop non-uniform oil reservoir comprising sulfate-reducing bacteria and hydrogen sulfide involves alternating pressure increase and pressure decrease intervals, wherein pressure is increased by water injection into injection wells with producing well shutdown and pressure is decreased by liquid extraction from producing wells with injection well shutdown. First of all oxygen-generation reagent having solved oxygen concentration of 250-700 g/m3 is injected in injection well. Then the well is stopped for time enough for hydrogen sulfide oxidation termination and sulfate-reducing bacteria killing. After that nutrient solution containing microorganisms and oxygen-generation reagent having 50-150 g/m3 of solved oxygen is supplied into injection well during pressure increase period so that injection is terminated simultaneously with pressure increase time finishing.

EFFECT: increased efficiency of reservoir treatment and decreased costs.

1 dwg

FIELD: oil and gas production.

SUBSTANCE: invention provides a method of developing oil pool allowing production of oil from water-rich oil reservoir under difficult geological-tectonic conditions in the last development stage. In the method, neutral salt of carbonic acid and acid solution are forced into formation through injecting well with water generated in gas-liquid fringe created in formation. After pumping of neutral salt of carbonic acid, acid solution is pumped by portions alternating with water pumping. Before pumping of acid solution portions beginning by at least second portion, selective insulation of high-permeable formation intervals is performed. Aforesaid neutral salt of carbonic acid utilized is sodium carbonate aqueous solution or aqueous suspension of calcium carbonate and aforesaid acid solution is aqueous hydrochloric acid solution. Selective insulation of high-permeable formation intervals involves use of freshly prepared controllable viscoelastic composition containing water-soluble acrylic polymer, cross-linking agent, thermal stabilizer, surfactant, and water. Summary concentration of acid solution is determined from concentration of neutral salt of carbonic acid on the base of stoichiometric proportions.

EFFECT: increased efficiency of maintaining formation pressure and thereby oil recovery of formation due to leveled displacement front and reduced probability of the rupture of formation rock backbone, and simplified control of phase state of gas-liquid fringe by changing pressure of pumped acid solution portions.

8 cl

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