Method of restriction of bottom water and annulus overflows in production wells
FIELD: oil and gas industry.
SUBSTANCE: invention refers to methods of restriction of bottom water and annulus overflows in production wells. The method consists in pumping water and solution of sodium naphthenate into a well; then the procedure is repeated not less, than 3 times; also cement solution is pumped with addition of sodium naphthenate; while initially solution of sodium naphthenate and water is pumped and then additionally alumo-chloride is pumped. Volume ratio of sodium naphthenate and alumo-chloride can be 4:1.
EFFECT: upgraded efficiency of method due to effect of hydrophobisation of porous space, increased amount of forming cementing material, thermo-stabilisation of this material under conditions of high temperatures of bed (above 80°C) and creating more reliable isolation screen.
2 cl, 2 tbl, 3 dwg
The invention relates to the oil and gas industry, in particular to methods of restriction and exclusion zones water production in oil and gas-condensate wells, by alternating pump downhole components of the gel-forming substances.
There is a method of limiting the inflow of formation water into the well, comprising the sequential injection in water-in-reservoir portions diesel oil or alkaline wastes and aqueous solution of calcium chloride [see SU 1328488 A1, EV 43/32, 1987]. In the basis of the method lies physico-chemical transformation of waste alkaline diesel or oil into a solid mass upon contact with formation water, activated calcium chloride.
The disadvantages of this method include low structural-mechanical and adhesive properties of the resulting plugging material.
These disadvantages are eliminated in the method of restricting plantar water and cross-flows in wells, chosen as a prototype [see EN No. 2172825 C1, EV 43/32, 2000] and including leaching wells and portions of the injection water, cement and calcium chloride, providing that the hole through the exposed filter pump salt solution of polyvalent metal (calcium chloride), then water, then naphthenate solution of sodium or potassium or a mixture, this procedureafter at least 3 times, then pump cement mortar shut on the water, water / cement ratio which varies between 0.2-0.6, 0.5-2 m31 m thick layer with the addition in the amount of 0.5-10% by volume of cement additional naphthenate solution of sodium or potassium or mixtures thereof with the ratio of the naphthenate : water 1:2, followed by bursting into the well of the total weight of the reservoir water at the rate of 1-2 m31 m thick layer, and then a rinsing wells, sealing the mouth and endurance under pressure 24 hours
The disadvantages of the prototype can be attributed to the fact that the resulting chemical reaction between solutions of sodium naphthenate and calcium chloride plugging material is not sufficiently resistant to high temperature reservoir (80°). The products of the interaction of the reagents are characterized by a small number of sediment yield (capsules (material), and therefore do not have sufficient structural-mechanical properties and water-holding capacity, over time, are subject to erosion formation water, which in turn reduces the life of the formed insulating screen.
The technical result of the proposed method limits plantar water and cross-flows in wells - increase the efficiency of the method due to the effect of waterproofing porous what about the space, increasing the number of generated plugging material, its thermal stabilization under conditions of high reservoir temperatures (above 80°and creating a more reliable waterproofing of the screen.
This result is achieved by a method of restricting plantar water and behind-the-casing flows into the borehole involves the same process operations as the prototype, is distinguished by the sequence of injection of the reagents for the formation of the waterproof area and applying a solution of a salt of polyvalent metal is aluminum chloride. Thus, the method involves the sequential injection into the well at the beginning of a solution of sodium naphthenate, then as a buffer - water, then the solution of salt of polyvalent metal is aluminum chloride, with a volumetric ratio of naphthenate to the aluminum chloride is 4:1, this procedure is repeated at least 3 times, and then pumped cement mortar shut on the water, water / cement ratio which varies between 0.2-0.6, 0.5-2 m31 m thick layer with the addition in the amount of 0.5-10% by volume of cement additional naphthenate solution of sodium or potassium or mixtures thereof with the ratio of the naphthenate : water 1:2, followed by bursting into the well of the total weight of the reservoir water at the rate of 1-2 m31 m thick layer, and then a rinsing wells the ins, sealing the mouth and endurance under pressure 24 hours
Comparative analysis with the prototype shows that the distinctive features of the new method of restricting plantar water and behind-the-casing flows into the well is a necessary and sufficient condition characterizing the novelty of the subject matter of the invention, namely the sequence of injection of the reagents for the formation of the waterproof area and used as a solution of salt of polyvalent metal solution of aluminum chloride.
The proposed sequence of injection of the reagents in the first place, of a solution of sodium naphthenate, contributes to the synergistic effect of the processing layer, namely the presence of hydrocarbons in the composition of the sodium naphthenate allows gidrofobizirovan the pore space of the reservoir, reducing permeability for water, which, along with subsequent formation as a result of interaction with a solution of aluminum chloride plugging material reduces the likelihood of a breakthrough of water.
The task of the invention is to improve the insulation quality of the water in the well by hydrophobization of the pore space, increasing the number of cementing substance and its strength under high reservoir temperatures.
A solution of sodium naphthenate is an aqueous solution of sodium salts of naphthenic acids in the mixture of the mineral oil. The technical product is mylonaft high-viscosity oils acidol. Mylonaft has a buttery consistency, easily soluble in water, its color varies from light brown to dark brown. Get milonoff of petroleum products by alkaline treatment of the distillate treated with sulfuric acid, or by treatment of the corresponding distillate oil (kerosene, diesel) sodium hydroxide solution. Aqueous solutions of malonate possess surface-active properties, detergent action, good emulsifying ability. Sodium salts of naphthenic acids in the reactions with the electrolytes dissolved in the formation water, form a voluminous precipitate, creating an impenetrable screen of water.
Alumoxane is the tonnage of waste production, a byproduct of the processes of petrochemical synthesis according to THE 38.302163-89. Alumoxane is a transparent liquid containing 20-25% of the mass. the basic substance or the powder of light yellow or greenish color with a faint odor of hydrochloric acid. Alumoxane refers to hazardous compounds (IV hazard class according to GOST 12.1.007-76), miliaresion, does not freeze at low temperatures.
To calculate the stoichiometric amount of sediment in the interaction of naphthenate with solutions of salts does not appear who is one. To determine the optimum ratio of reactants, which is the formation of a maximum quantity of sludge produced by the interaction of aqueous solutions of salts of polyvalent metals (prototype - chloride and calcium - aluminium chloride) and a solution of sodium naphthenate were conducted the following laboratory tests. In a test tube was poured aqueous solutions of salts 10 cm3then added an aqueous solution of sodium naphthenate according to the scheme given in table 1. After the reaction has determined the amount of loose sediment, neasdon fluid and pH. The studies determined the volumetric ratio of sodium naphthenate solution of aluminum chloride 4:1 for maximum mass and volume of the sediment yield. When the interaction of these reagents under other equal conditions and equal volume ratios (4:1) increase the yield of the precipitate volume is 30%, by weight of 25% compared with the solution of calcium chloride on the prototype. PH pH neasdon fluid through 24 hours is restored to 8. Further, we point at a temperature of 80°With a mixture of reagents in a volume ratio of 4:1 sodium naphthenate and calcium chloride (the prototype) and sodium naphthenate and aluminum chloride (proposed method). In the first case there is postinnovation sediment under the influence of temperature.
Increasing the yield of the precipitate (plugging material) compared to the prototype in the interaction of the reagents is due to the special chemical properties of aluminium chloride, the molecules of which have a dimeric structure with covalent number 4 (Al2Cl6). In solutions of aluminium salts hydrolyzed with the formation of the complex:
In the interaction of the hydrolyzed form of aluminum chloride with sodium salts of naphthenic acids forms a strong complex. The prototype calcium chloride, participating in the exchange reaction joins two molecules of sodium naphthenate, because the valence of calcium +2, whereas aluminium chloride attaches four molecules of sodium naphthenate.
At the same time in the flushed zone, the formation of a precipitate of aluminium hydroxide Al(OH)3that adhesive on the surface of the pore channels, in addition to creating a waterproof area.
For methods of limiting water inflow main parameters determining the amount of filtration of produced water into the well per unit of time, are the permeability of rocks in the bottom zone of the collector on the water after the event water shutoff and minimum pressure gradient filter.
The method was verified in the laboratory by installing three-phase filter, ru is ment to simulate temperature and pressure conditions of the reservoir. The proposed formulation was tested on samples of core, pre-saturated formation water at a temperature of 80°C. Initially measured the permeability of water-saturated models for gas, water, and then carried out the injection of reagents and after exposure to the reverse reaction measured permeability for water. The results of laboratory studies insulating effect on the proposed formulation of the invention is 65-94%, while the minimum gradient filtering water remained at the same level. The prototype insulating effect is 35%, with a minimum gradient of water filtration decreased 1.5 times (table 2). In figure 1, 2, 3 shows graphs of the coefficient of filtration of samples of cores in the modeling process water shut-off prototype and the proposed method of the invention.
As can be seen from the above data, the use of solutions of sodium naphthenate and aluminum chloride leads to better technical result increased insulating effect washed in high temperature zones of the reservoir rocks and, ultimately, increase the production parameters wells.
|The results of determining the volumetric quantity of sludge produced by the interaction of aqueous solutions of salts is polivalente metals and a solution of sodium naphthenate|
|no experience||The name of the solution of the metal Vsolution= 10 cm3||Volume of an aqueous solution of sodium naphthenate, cm3||The volume of solution General, cm3||The volume of filtrate, cm3||The amount of sludge, cm3||the pH of the filtrate, pH||Note|
|1||An aqueous solution of calcium chloride 20% (the prototype)||10||19||18,8||0,2||7,5||Under other equal conditions and equal volume ratios (4:1) increase the output of sediment by volume 30%|
|6||An aqueous solution of aluminum chloride 20%||10||20||18,1||1,9||3|
|The way to handle||Permeability after treatment, μm2||The minimum pressure gradient filter, MPa/m|
1. A method of restricting plantar water and cross-flows in wells, including injection into the well water, a solution of sodium naphthenate, the same procedure is repeated at least 3 times, followed by the injection of cement mortar with addition of sodium naphthenate, wherein the first downhole pump solution of sodium naphthenate, water, then advanced alumoxane.
2. The method according to claim 1, characterized in that the volume ratio of sodium naphthenate and aluminum chloride is 4:1.
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.
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.
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.
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.
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: oil and gas industry.
SUBSTANCE: invention refers to oil and gas industry, particularly to methods of eliminating zones of loss in well and can be implemented for isolation of zones of loss of formation at capital repair of producing and pressure wells and also at regulating profile injection capacity of pressure wells and isolation of water floods in producing wells. According to the method of eliminating zones of loss in a well liquid glass is successively pumped into the well with density of 1360-1450 kg/m3, then liquid glass with density of 1100-1200 kg/m3, and silicon-organic reagent ACOR-BN 102 with density of 980-1100 kg/m3, with following fixing in bed water. The composition is used at a following ratio of components, volume %: liquid glass with density of 1360-1450 kg/m3 10-20, liquid glass with density of 1100-1200 kg/m3 10-20, silicon-organic reagent ACOR-BN 102 with density of 980-1100 kg/m3 60-80. Between liquid glass and silicon-organic reagent ACOR-BN 102 a buffer of fresh water is pumped.
EFFECT: eliminating intensive zones of loss in well.
FIELD: mechanics, mining.
SUBSTANCE: invention is designed to apply process compositions onto weal walls containing solid phase. The proposed device comprises a tubular casing with colmataging nozzles, a swirler with deflectors swirling the jet made from hard-alloy material and arranged in the casing, a branch pipe with slit-like holes fitted behind the swirler. The said swirler represents a replaceable tube with tangential openings. The walls of aforesaid colmataging nozzles fitted in sleeves pressed in the casing wall opposite to each other in between the casing wall and branch pipe, feature two tangential openings intended for repeated swirling of the drill fluid.
EFFECT: higher efficiency of well packing.
FIELD: oil and gas industry.
SUBSTANCE: invention refers to oil-producing industry, specifically to method of selective water shut-off within producing oils well with using gelling compositions. According to method of selective water shut-off within producing oils well by pumping-in gelling composition produced from mixed polyacrylamide, carbamide, aluminium salts and water. Aluminium salt is aluminium pentahydroxocloride. The specified mixture is carried out while carbamide is introduced into polymer- colloidal complex produced from mixed aqueous solution of polyacrylamide and aqueous colloidal solution of aluminium pentahydroxocloride is ratio as follows, wt %: aluminium pentahydroxocloride 3-6, polyacrylamide 0.25-0.5, carbamide 7-14, water - the rest.
EFFECT: higher reservoir recovery.
2 dwg, 5 ex, 4 tbl
FIELD: oil and gas industry.
SUBSTANCE: invention is related to oil industry and may find application in development of non-uniform watered oil pool. According to method, oil pool is watered, oil-bitumen product is pumped into edging layer, and oil is withdrawn from producing layers. Heat-insulated pipes are lowered into vertical part of cavity, through which unheated low-viscosity oil is squeezed into developed pool layer, oil-bitumen product is squeezed in heated form, and unheated low-viscosity oil of developed pool is squeezed. Squeezing is done into upper part of producing layer not lower than water and oil contact. Oil-bitumen product is mixture of oil-bitumen and cement in ratio of 1:(0.3-0.7), accordingly, by volume. Per 1 running meter of oil-saturated part 1.2-2.0 m3 of oil-bitumen and cement mixture is used. Pumping is done until pressure increases at well collar to value equal to hydrostatic pressure ±30%. Technological holding is carried out until cement hardens. Well development is done cyclically: flushing with oil and oil withdrawal for 1-2 days - stop for 1-2 days with number of cycles from 2 to 4, after that continuous oil withdrawal is started. If pressure of oil-bitumen product reduces and well capacity increases, operations with oil-bitumen product are repeated.
EFFECT: increase of pool oil recovery.
2 cl, 2 ex
FIELD: oil and gas industry.
SUBSTANCE: invention is related to oil industry and may find application in operation and making of well horizontal hole in oil beds, where areas of drilling agent absorption are available. Substance of invention: when isolating area of complete drain, at first mixture of oil, cement and calcium chloride is pumped in the following ratio: oil:cement:calcium chloride as 1:(1-4):(0.002-0.24) by volume - accordingly in volume of 6-12 m3. Mixture is held for 12-14 hours. Then cement mortar is pumped in, containing 2-6% of calcium chloride in volume of 6-18 m3 and held for up to 2 days. Well operation in the first 10 days in done at minimum flows and pressures, at which well operation is possible.
EFFECT: better reliability of complete drilling agent drain area isolation, increase of well debit and reduction of time required for oil resources workout.
FIELD: petroleum industry.
SUBSTANCE: invention relates to oil production industry and can be used both for repair insulation work and for isolation of water inflows and absorption zone in injection and production wells. The polymer compound contains (% by weight): acetone-formaldehyde resin 60-93, amino-formaldehyde resin 1.86-30, alkaline hardener 0.4-2, water - residual, the acetone-formaldehyde resin/amino-formaldehyde resin ratio being 1:0.02÷0.5.
EFFECT: increased efficiency and quality of isolation of the absorption zones and repair insulation work.
1 tbl, 6 ex
FIELD: oil and gas industry.
SUBSTANCE: suggested method refers to oil and gas producing industry and is designed for repair and isolating works in oil and gas wells, particularly for isolation of water producing zones in an oil well. A sodium silicate block is preliminary dissolved in presence of water at heating and continuous mixing. Then a polyacrylonitrile raw material and caustic soda are simultaneously introduced at a following ratio of components, mas.%: a sodium silicate block 10.0-20.0; water 65.0-85.0; a polyacrylonitrile raw material 3.0-8.0; caustic soda 2.0-5.0.
EFFECT: increased efficiency of water isolating operations due to improved isolating characteristics, to increased mechanical strength of a backfill mass, formed at structuring of obtained backfill material, with simultaneous upgraded heat resistance and reduced cost of the said material.
SUBSTANCE: invention is designed for oil, gas and water insulation of wells. Method of productive formation insulation during cementation of a casing pipe involves downtake of a casing pipe equipped with reverse valves at the pipe bottom into a well, subsequent inflating of cement grout with a by-pass plug, working substance of density equal to the cement grout, with a by-pass plug, followed by displacement fluid until the reverse valves are blocked by the by-pass plug inserted over the working substance. The working substance is a cement grout with hollows filled with water or oil and sand mixture solidified by freezing. After the solidification is complete the cement grout is matured until the mentioned water or oil and sand mixture melts under the external influence, and then the formation is penetrated and depression cleaning is implemented.
EFFECT: improved reliability and efficiency of insulation method, including insulation in wells in high-intake producing formations.
FIELD: oil and gas industry.
SUBSTANCE: invention is referred to a petroleum industry and can be applied at repair of holes from water inflow by abandonment of leakage of production strings and annulus room. Technical result - reception of high and durable insulating effect during repairing works of holes from water inflow. In a method of isolation of a water influx in a hole at the leakage of production strings including an injection in a leakage zone grouting mixture, containing formaldehyde resin and a hardener-acid with a preliminary purification of this zone by an injection of the pointed acid. The grouting mixture contains complementary hydrolytic gypsum. And an injection of the pointed acid and grouting mixtures hold in a continuum mode at stress, above breakdown pressure of this formation, with the subsequent hardening of grouting mixtures without a decompression. The invention is developed in dependent posts.
EFFECT: reliability increase of isolation at repairing works of holes from water inflow.
3 cl, 2 tbl
FIELD: mining engineering, oil industry.
SUBSTANCE: invention refers to oil industry, specifically to well inflow areas isolation. Technological result is increase of inflow isolation efficiency. Well inflow areas isolation technique including polymer pumping of well, polymer gelatinization curing and further strengthening with cement suspension implies using of polymer composition of viscosity not more 15-20 MPa. Polymer composition is pumped between oil separation layers and further driven to critical area by oil pressure 0.6-0.8 MPa for pore space treatment, curing in specified area is carried out as formation pressure is equal to well pressure.
EFFECT: increase of inflow isolation efficiency.
FIELD: oil and gas production.
SUBSTANCE: invention relates to grouting mortars used for cementing casing pipes of gas, gas-condensate, and oil wells complicated by presence of formations with low hydraulic rupture pressure as well as presence of permafrost rocks. Light-weight grouting mortar contains 47.0-60.0% special-type cement, 6.6-11.8% clinoptilite as light-weight additive, and water. As a result, casing-pipe annulus incidents during boring and running wells are avoided owing to improved parameters of grouting cement, in particular increased sedimentation stability of mortar, dimensional stability and needed strength of cement stone at low positive and negative temperature in early hardening stages are achieved at simultaneous lowering of grouting mortar density.
EFFECT: improved performance characteristics of grouting mortar.