Treatment method of bottom-hole formation zone. RU patent 2494245.
 Treatment method of bottom-hole formation zone / 2494244In a treatment method of a bottom-hole formation zone, which involves pumping to the formation of acid-oil emulsion of reverse type and acid, as acid-oil emulsion of reverse type there used is emulsion containing the following components, wt %: dispersion medium - hydrocarbon liquid 31-38, emulsifier - reaction products of aliphatic amines of fat acids of hydrated tall oil with hydrochloric acid in terms of amines 0.02-0.08, dispersion medium - synthetic, inhibited hydrochloric acid (10-18%) is the rest. |
| Method for near well-bore treatment with acid / 2490444 Method for near well-bore treatment with acid involves at the first stage pumping into the well of 10-15% aqueous solution of hydrogen chloride in a volume calculated on the basis of 0.25-0.5 m3 per 1 running metre of penetrated stratum depth; at the second stage - pumping of 10-15% aqueous solution of hydrogen chloride with a retarder of the acid reaction with rock in the volume of 2-5% of acid solution volume in total volume of pumping calculated on the basis of 1-1.5 m3 per 1 running metre of penetrated stratum depth at initial pressure equal to the final pressure value during pumping at the previous stage; overflushing by oil in volume of 5-15 m3 at initial pressure equal to the final pressure value during pumping at the previous stage; soaking during 16-48 hours and input of the well into operation. |
 Procedure for treatment of bottomhole zone of producer with two wellheads / 2490443In procedure for treatment of bottomhole zone with two wellheads in case of failure of an electric-centrifugal pump (ECP) with no apparent deviation in its operating parameters and in case of alkalinity growth for extracted product up to pH>7 the required volume of hydrogen chloride solution is calculated on the basis of a length and diameter of the well filtering part; the required volume of hydrogen chloride solution is selected to treat the whole volume of the strainer; the required volume of flush fluid is calculated for delivery of compounds into a slope wellhead. ECP is shutdown at the vertical wellhead before pumping of hydrogen chloride solution is started. The required volume of hydrogen chloride solution is carried out into tubular annulus from the side of the vertical wellhead. When pumping of hydrogen chloride solution is over extraction from the slope wellhead is increased and ECP is started from the vertical wellhead. ECP is stopped at the vertical wellhead and hydrogen chloride solution is overflushed by the flush fluid into filtering part of the well. After ECP startup in enlarged extraction rate from the slope wellhead samples are taken periodically in order to check pH value, monitor dynamics in changes of fluid supply from the slope wellhead. When pH value id recovered up to the normal value ECP is started into operation from the vertical wellhead and supply from the slope wellhead is returned back to normal operation mode. |
| Method for well completion / 2490442 In method for well completion including pumping of acid solution into open horizontal hole in the mode of jet impact such impact is attained due to a jet delivery by a jet nozzle at the end of a flexible flush-joint pipe. The nozzle is placed at the borehole bottom. The acid solution is pumped with circulation through the well mouth; while acid solution is circulating the flexible flush-joint pipe is lifted simultaneously from the well with the speed not exceeding speed of the borehole filling by the acid solution. When horizontal hole is filled with the acid solution, the solution is overflushed into the stratum with staged pressure build-up and exposure at each stage. The flexible flush-joint pipe with a nozzle is placed again at the borehole bottom and the operation of borehole filling and overflushing is repeated again. Soaking takes place so that acid solution could react with the rock. The flexible flush-joint pipe is lifted to the interval of inert gas pumping, an inert gas is pumped and a build-up curve is recorded. Cyclic well killing is carried out in the mode of water pumping - soaking - oil draining till complete oil drain; thereafter a submerged pump is run-in and the well is input into operation. |
 Device for treatment of bottomhole formation zone of a well and method for treatment of bottomhole formation zone of well / 2487237Device for treatment of bottomwhole formation zone contains an air chamber with atmosphere pressure and length of 20-50 m connected to the first additional perforated chamber with seal layer, solid heat generating compound A with flame igniter, combustible high-strength compound B and breakable calibrated membrane located inside; the first added perforated chamber by means of a coupling with holes is connected to the second added inlet chamber with combustible high-strength compound C, igniter and breakable calibrated membrane located inside; the second additional perforated chamber by means of a coupling with added air chamber with length of 1.5-3 m connected by means of a coupling and metal adapter with to inlet chamber that is made of elastic plastic material with seal layer, solid acid generating compound D with igniter located inside; in the metal adapter there are drilled holes; compound A generated heat and gas of the following components by wt %: ammonium nitrate 35; sodium bichromate 2; barium nitrate 15; aluminium ASD-1 1.5; iron-aluminium thermite 31; epoxide compound (mixture of ED-20 tar, EDOS plasticiser and AF-2M hardener) 15.5; compound B is made of the following components by wt %: ammonium nitrate 30-40, calcium carbonate 5-10, the above epoxide compound 50-65; inside the added inlet chamber there is a layer of glass sealant and solid gas generating compound E made of the following compounds by wt %: ammonium nitrate 70, sodium bichromate 1, the above epoxide compound 29; compound C is made of the same composition as compound B; compound D is made as thermal-gas-chemical solid fuel with a layer of glass sealant and a layer of epoxide compound on top of it; the above fuel consists of the following components by wt %: ammonium nitrate 12-16, lithium fluoride 1-3, barium nitrate 5-8, aluminium ASD-1 0.7-0.8, iron-aluminium thermite 14-16, hexachlorane 20-30, polytetrafluoroethylene 20-30, the above epoxide compound 5-10. The method for treatment of bottomhole zone (BHZ) includes delivery of the above device by a wireline, combustion of compound D and formation of maximum quantity of chemical agents, holding for the purpose of reaction of acids produced during combustion with BHZ formation, running with installation of the coupling with holes at the level of treated stratum, opening of the chamber with length of 20-50 m, actuation of breakable calibrated membrane in result of layer-by-layer combustion of compounds A and B with implosion treatment of BHZ, removal of impurities from bottomhole stratum; during holding thermal-gas-chemical impact acts on the stratum for 30 minutes ad pressure can be corrected due to availability of holes in the metal adapter at fixed position of the above fuel inside the inlet chamber due to the above layers of sealant and compound with formation of gases heated up to high temperatures at high pressure within treatment range; opening of the chamber with length of 1.5-3 m is carried out by sequential actuation of the igniter, compounds E and C and breakable calibrated membrane located in the second added inlet chamber; after hydraulic shock there's another holding of the process for 30 minutes; when the chamber with length of 20-50 m is opened combustion of compound A takes place with formation of gases heated up to high temperature at high pressure within treatment range. |
 Stimulation method of formation fluid influx from well / 2485305Stimulation method of formation fluid influx from the well consists in lowering to the well of a tubing string. Counter pressure on the productive formation is decreased owing to replacing the liquid column with liquid-gas mixture (LGM) at observance of the required value of depression on the productive formation. Before the tubing string is lowered, its lower end is equipped with a remote subsurface pressure gauge and a filter. The tubing string is lowered to the well so that the filter is located opposite the formation perforation interval; after that, treatment of the bottom-hole zone of the formation is performed using a chemical method with process exposure for reaction. Then, the tubing string is lowered further so that the filter is located below the formation bottom, and into the inter-string space there lowered is a string of flexible tubes (FT) 100 m below the liquid level in the well. The liquid column is replaced in the inter-string space of the well with LGW and lowering of the FT string is continued. When lower end of the filter of the tubing string is reached, lowering of the FT string is stopped; then, stimulation of the formation fluid influx is started by gradual reduction of density of pumped LGM till the required depression on the productive formation, which is controlled as per readings of the remote subsurface pressure gauge, is achieved. After completion of stimulation of the influx from the well there removed is FT string from the inter-string space of the well, and operating equipment is lowered to the well and the well is put into operation. |
| Method for reagent clay cake removal from well / 2484244 Method for reagent clay cake removal from a well involves preliminary lowering of the tubing to lower perforation holes, formation in the zone of perforation holes of the first bath by pumping to the well via the tubing of a clay cake removing solution, its exposure, removal, further formation in the same zone of the second bath of water solution of acid with its being forced through the perforation zone to the formation and removal of the second bath by flushing; development of the well. As the clay cake removing solution, water solution of caustic soda with addition of surface active substance (SAS) is used. When the tubing is being lowered to the ell, it is equipped with a packer. Then, at open casing valve there performed is formation of the first bath by pumping of the above water solution of caustic soda via the tubing string, and the specified water solution of caustic soda is delivered to the formation by its being forced with process liquid via the tubing. Them the packer is set at the depth of not less than 50 metres above the treated formation, and forcing of water solution of caustic soda is performed with process liquid to the formation without exceeding allowable pressure on the formation; then, the well is kept for 10 hours for reaction under pressure not exceeding allowable pressure on the formation. Then, the packer is unpacked, and the working face is flushed by reverse flushing with process water by additional lowering of the tubing to the distance of 1-1.5 metres till the working face. Then, the packer is lifted so that it can be located at the depth of not less than 50 metres above the formation. Then, in the same zone there formed is the second bath by pumping of clay-acid solution with addition of Katapin KI-1 reagent on the basis of the fact that volume of clay-acid solution shall be 0.5-1 m3 per metre of the formation. The above clay-acid solution is forced with process fluid via the tubing to the formation; then, the packer is set and forcing of clay-acid solution is performed with process fluid to the formation without exceeding allowable pressure on the formation. Reaction exposure is performed during 1-2 hours. Then, well swabbing is performed via the tubing in the volume of 1.5-2 of the well volume. Then, the well injection capacity is determined at the pressure not exceeding maximum allowable pressure on the formation. When the required well injection capacity is not achieved, the above operations are repeated maximum for three times till the required well injection capacity is achieved. |
| Method for increasing oil recovery of deposit in carbonate reservoirs of fracture-pore type / 2482269 Method for increasing oil recovery of the deposit in carbonate reservoirs of fracture-pore type involves formation of a group of production wells with an injection well in the centre so that the injection well can be located in the lower part of the deposit structure in relation to production wells, oil recovery from the group of wells watered out with bottom water, forced extraction of fluid from the injection well till the response of the neighbouring wells to that action and reduction of formation pressure in the area of responding production wells. After steady reduction of formation pressure in the area of responding production wells by more than 10 %, each of them is pumped with waterproof compound that is strengthened under action of chlorhydric acid in the volume of 15-20 m3. After waterproof compound is cured, forced extraction of the fluid is stopped and acid bearing compound in the volume of 0.4-1.0 m3 per metre of oil saturated part of the formation is pumped to each well treated with waterproof compound. Responding production wells are brought into operation. |
| Method for bottom-hole zone treatment / 2477787 Method for formation bottom-hole area treatment includes mounting of oil-well tubing in the well below perforation holes, determination of technical condition of production string and character of production formation saturation in perforation zone on the base of geological-geophysical researches data, pumping and squeezing down to the formation water solution of alkali metal supersalt with holding for reaction for 10-12 h, extraction of reaction products from bottom-hole area by well blowing by inert gas or gas from well-donor through casing annulus, pumping and squeezing down to the formation hydrogen chloride, holding for reaction for 6-8 h, well development by gas from well-donor or inert gas. |
 Acidic aqueous solution containing chelating agent and use thereof / 2476475Invention relates to an acidic aqueous solution containing a chelating agent and an acid, wherein the chelating agent is glutamic N,N-diacetic acid (GLDA) or a salt thereof and wherein the amount of GLDA or the salt thereof is 20-60 wt %, based on the weight of the aqueous solution, and wherein the acid is selected from hydrochloric acid, hydrobromic acid, hydrofluoric acid, hydroiodic acid, sulphuric acid, nitric acid, phosphoric acid, formic acid, acetic acid, citric acid, lactic acid, malic acid, tartaric acid, maleic acid, boric acid, hydrogen sulphide or a mixture of two or more of these acids, and use of said solution in cleaning processes, precipitation processes or processes of removing salt deposits, at oil fields in completion and stimulation by acid treatment, fracturing and/or deposit removal. The acidic aqueous solution has pH below 3. |
| Treatment method of bottom-hole formation zone / 2494244 In a treatment method of a bottom-hole formation zone, which involves pumping to the formation of acid-oil emulsion of reverse type and acid, as acid-oil emulsion of reverse type there used is emulsion containing the following components, wt %: dispersion medium - hydrocarbon liquid 31-38, emulsifier - reaction products of aliphatic amines of fat acids of hydrated tall oil with hydrochloric acid in terms of amines 0.02-0.08, dispersion medium - synthetic, inhibited hydrochloric acid (10-18%) is the rest. |
| Isolation method of water influx zones in well / 2494229 Isolation method of water influx zones in a well consists in pumping to an isolated formation of water solution of calcium chloride with density of not less than 1500 kg/m3, which is warmed up to the temperature of 70-90°C. After pumping of water solution of calcium chloride exposure is performed during 8-12 h. Then, a bank of hydrocarbon liquid and liquid sodium glass heated to the temperature of 70-90°C is pumped in series and exposure is performed during 24-48 h for formation of gel in the whole volume of liquid sodium glass. |
| Preparation method of composition for isolation of lost-circulation zones in well / 2494228 Preparation method of a compound for isolation of lost-circulation zones in a well by mixing cement, clay powder, polyacrylamide, water and an additive. First, water solution of the additive is prepared by introducing the latter to water; then, at mixing clay powder and cement is added in series to the above water; mixture is mixed during at least 30 minutes and then, powder-like polyacrylamide is added; sodium metasilicate is used as an additive, and clay powder providing the yield of clay mortar with viscosity of 20 mPa·s of less than 5.0 m3/t is used as clay powder at the following component ratio, wt %: the above clay powder - 60-80, cement - 15-20, the above additive - 10-20, powder-like polyacrylamide - 0.005-0.01, and water - 100. |
| Method for limiting water influx in well / 2494225 Method for limiting water influx in a well involves portion pumping to the isolation interval of composition and gel-forming regulator. Composition contains hydrolysed polyacrylonitrile - 100 parts by volume, liquid glass - 20-50 parts by volume, polyacrylamide DP9-8177 - 50-100 parts by volume. Aluminium oxychloride in the amount of 200-300 parts by volume is used as gel-forming regulator. |
| Isolation method of well troublesome zone with carbonate basins / 2494224 Method consists in series pumping to a well of portions of water solution of a structure-forming reagent and a structure former, which are separated with fresh water bank. Water solution of the structure-forming reagent and the structure former is forced through to isolated interval by pumping of displacement fluid. First, water solution of hydroxochloric aluminium is pumped to the formation and left for the time period of reaction with carbonate basin. Pumping and forcing-through of water solution of structure-forming reagent and structure former is performed in a pulse mode. After pumping of every 0.5-1.5 m3 of displacement fluid to the isolated interval is performed, periodic relief of the formation excess pressure is performed by opening the well with outflow of displacement fluid via the tubing through a nozzle to a ground reservoir. Then, pumping of displacement fluid is continued after its outflow ends. At each next relief the pressure value, by which the relief is performed, is increased by 0.4-0.6 MPa. |
 Surface-active acid composition for treatment of carbonate basins / 2494136Surface-active acid composition for treatment of carbonate basins contains the following, wt %: hydrochloric acid (in terms of HCl) 6.0-24.0; alcohol-containing compound 5.0-30.0; surface-active substance - SAS, commercial washing agent "ZheniLen" 0.5-2.0; cationic surface-active substance - OksiPAV or Don-96 0.2-1.0; iron stabiliser 0.5-3.0; water is the rest. |
 Biocide-based injection composition for wells and well processing methods / 2494135Aqueous composition for well operation, meant for pumping into an operating well, contains: water, a polymer selected from a group consisting of galactomannan polymers, galactomannan polymer derivatives, starch, xanthane gum, hydroxy cellulose, hydroxyalkyl cellulose, polyvinyl alcohol polymers, vinyl alcohol and vinyl acetate copolymers, and polymers which are a product of polymerisation of one or more monomers selected from a group consisting of vinyl pyrrolidone, 2-acrylamide-2-methylpropane sulphonic acid, acrylic acid and acrylamide, a biocide consisting of 3,5-dimethyl-1,3,5-thiadiazine-2-thione in an amount which is effective to inhibit bacterial growth. The method of inhibiting bacterial contamination using the aqueous composition for operating wells, meant for pumping into an operating well, involves adding an amount of biocide, consisting of 3,5-dimethyl-1,3,5-thiadiazine-2-thione, which is effective to inhibit bacterial growth, into the aqueous composition for operating wells and pumping said aqueous composition into an operating well. |
| Method for prevention of casing gas, oil and water inflows in oil and gas wells / 2493354 Method consists in filling the casing space with a clay mud above a cement mixture. What is used is non-stabilised barite-weighted clay mud pumped during the process of cementing to create a barite block. The volume of the weighted clay mud is not less than that of the tubing-casing annulus above cement. |
| Method for making polymer-coated proppant / 2493191 Method for making a polymer-coated proppant involves coating the granules with a polymer of phenol formaldehyde resin with hexamethylenetetramine and liquid epoxy resin with a hardener; coating the granules is preceded by preparing a solution of phenol formaldehyde resin with hexamethylenetetramine, which is mixed with liquid epoxy resin with the hardener in ratio, wt %: liquid epoxy resin with the hardener 20-80 and the solution of phenol formaldehyde resin with hexamethylenetetramine 20-80 with the solvent content in the solution of phenol formaldehyde resin makes 5-90%. The invention is developed in the secondary claims. |
 Methods for using additives containing microgels for controlling fluid loss / 2493190Mud solution containing an aqueous fluid and an additive to control fluid loss, containing at least one polymer microgel comprising a reaction product prepared by a polymerisation reaction of a polymer or a copolymer and a crosslinking agent, wherein the polymer or copolymer comprises at least one unit of at least one compound from a group of: polybutylene succinate, polybutylene succinate-co-adipate, polyhydroxy-butyrate-valerate, polyhydroxy-butyrate-covalerate, polyester amides, polyethylene terephthalates, sulphonated polyethylene terephthalate, polypropylene, aliphatic aromatic copolyester, chitins, chitosans, proteins, aliphatic polyesters, poly(hydroxyester ethers), poly(hydroxybutyrates), poly(anhydrides), poly(orthoesters), poly(amino acids), poly(phosphazenes), a copolymer thereof, a homopolymer thereof, a tetrapolymer thereof, and any derivative thereof. The method involves: preparing an aqueous compound for well treatment and containing the above additive, introducing the compound into a downhole formation, thereby allowing the additive to flow into a filter cake on the surface inside the downhole formation, allowing the filter cake to degrade, and extracting hydrocarbons from the formations. The method involves preparing the above mud solution, introducing it into the downhole formation, allowing the additive to flow into the filter cake on the surface inside the downhole formation, allowing the filter cake to degrade, and extracting hydrocarbons from the formation. The method involves preparing a filter thickener containing the above aqueous fluid and the additive, placing the thickener into the downhole formation with gravel packed filtration and a portion of the downhole formation. The invention is developed in the secondary claims. |
| Drilling foam composition / 2268283 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. |
FIELD: oil and gas industry.
SUBSTANCE: acid treatment method of a bottom-hole formation zone involves pumping to the formation of emulsion and water solution of an acid; at that, first, water solution of acid is pumped, and pumping of water solution of acid and emulsion is performed in a series-and-alternating mode, and emulsion containing the following components, wt %, is used as emulsion: acid 5.0-40.0; emulsifier - anionic or nonionic, or cationic surface-active substance, or their mixture 1.0-10.0; hydrocarbon solvent 5.0-40.0; decomposer - primary or secondary alcohol or their mixture 0.1-5.0; corrosion inhibitor 0.01-0.05 and water is the rest. Emulsion can contain viscosity regulator in the quantity of 0.01-6.0 wt %. Water solution of acid with concentration of 3.0-24.0% is used.
EFFECT: deceleration of a reaction of acid with rock of the formation, enlarging the treatment coverage range as to thickness and depth of the formation using an emulsion, preserving stability, reducing intensity of acid corrosion and having washing effectiveness in relation to asphaltene-resin-wax-bearing deposits.
3 cl, 3 tbl, 29 ex
Field : oil producing industry and can be used for acid treatment of bottom-hole formation zone, presented heterogeneous permeability carbonate and terrigenous reservoirs.
A method of processing the well bottom zone in multilayer oil Deposit, including the pumping of oil emulsion all layers, further material, the solvent and the oil component of the oil emulsion, and acid solution, which is injected in oil reservoirs (see Patent of Russian Federation №2092686, MKI 21 43/27, publ. 1997).
This method is not efficient enough because of the complicated processing three different compositions, did not provide a selective penetration of acid in the oil-saturated interlayer and lock emulsion pays. Moreover, loaded emulsion remains in the oil reservoir and worsens its filtration characteristics.
There is a method of acid treatment of bottom-hole formation zone, including, sequential injection emulsion of the following composition, mass%: hydrochloric acid 15-20%concentration - 44.1kHz-51,1, carboxymethylcellulose 1.5 to 2.5,and water - 46,4-54,4 and acid composition that contains, mass%: hydrochloric acid 15-20%concentration, an acid benzojnuju 0,25-0,5 concentration and water - 42,9-62,25 (see RF Patent №2269648, MKI 21 43/27, publ. 2006).
However, a well-known method for technical result aims to increase the depth of penetration of the emulsion into the reservoir by changing the wettability of the breed. There is no effective redistribution of filtration flows, acid emulsion enters the water saturated plot collector and does not cover the reservoir.
Closest to the proposed invention of technical nature and the achieved result is a method treatment of bottomhole formation zone, including injection into the reservoir reverse oil emulsion and water solution acid, where as the inverse emulsion use emulsion, which contains the following components,%: hydrocarbon liquid 26-40, emulsifier -9601 or 9701-0,4-5,0, aqueous solution of inhibited 10%hydrochloric acid or or aqueous solution 1-10%solution of calcium chloride or sodium chloride - the rest (see RF Patent №2255215, MKI 21 43/27, publ. 2005).
However, application of this method is limited, since the time of the breakup emulsions are unregulated depending on the temperature, viscosity and solve technological tasks, the result could be the deterioration of filtration properties of the manifold due to contamination used emulsion, which is not destroyed after the treatment well. Also at the high content of iron in the bottomhole zone the emulsion has a tendency to resinification that leads to sedimentation of oil pays resins, the reaction products of oil with acid in the presence of ions of iron, especially these processes are significant at elevated temperatures.
Purpose the invention is to provide a way of processing of bottom-hole formation zone with high efficiency by slowing the speed of the reaction of acid to the reservoir rock, increase coverage of treatment in thickness and depth of the reservoir, with the use of emulsion, preserving stable up to 120 hours at a temperature up to 60 C, which reduces the intensity of acid corrosion, and has a washing effective against .
This goal is achieved through the creation of a way of processing of bottom-hole formation zone, including injection into the reservoir emulsion and water solution acid, and initially injected water solution of acid, and the pumping of water solution of acid and emulsion is carried out in a series-striped mode and as use emulsion emulsion of the following composition, mass%:
Acid- 5,0-40,0
or nonionic
or cationic surfactant
or a mixture
- 1,0-10,0
Hydrocarbon solvent
- 5,0-40,0
Primary or secondary alcohol
or a mixture
- 0,1-5,0
Corrosion inhibitor
- 0,01-0,05
Water- the rest.
In the options for the application of ways emulsion may contain viscosity regulator in the amount of 0.01-6,0 mass%, and acid aqueous solution uses 3.0-24,0%concentration.
As a water solution of acid use aqueous hydrochloric acid or mixtures of hydrochloric and hydrofluoric acids, depending on the reservoir rock.
To the emulsion as acid is used:
- hydrochloric acid GOST 857-95;
- hydrofluoric acid GOST 10484-78;
- acid TU 2121-083-05800142-2001;
- acetic acid GOST 19814-74;
- formic acid GOST 1706-78;
- mix of the two.
Use surfactants or nonionic surfactants or cationic surfactants or their mixtures, such as: TU 6-09-1514-75; - 5K TU 2483-064-0580977-2003; emulsifier cationic bitumen emulsions (Б) TU 0257-007-35475596-98; -04 TU 2458-003-27913102-2003; - monoamine fatty acids of coconut oil, the production of China. - Amdor TU 0257-003-35475596-96.
As a hydrocarbon solvent use:
- diesel fuel (DT) in accordance with GOST 305-82;
- xylene GOST 9410-78;
MIA-prom TU 4852-01127913102-2001;
- toluene GOST 14710-78;
- gasoline on the other 0251-009-057-66801-93;
- the faction of aromatic hydrocarbons (FAA) TU 2414-00352927048-2005;
- mix of the two.
Primary or secondary alcohols enter in structure to regulate the speed of the collapse of the emulsion with the formation of the mobile inorganic and hydrocarbon phases. As primary or secondary alcohols use for example: - methanol GOST 2222-95; - isopropanol TU 6-09-50-2655-94;
- secondary butanol GOST 6006-78;
- TU 6-01-646-84;
- GOST 8313-88; or their mixture.
As a corrosion inhibitor is used:
- Dodicor -2575 - product company «Clariant», USA;
- Prod Ci-300 - a product of the company «Chevron Fillips, USA:
- methenamine GOST 1381-73;
- formaldehyde GOST 1625-89;
fatty ammonium salt.
As a regulator of viscosity can be used:
- ES-3 TU 38-5901268-90;
- biopolymer TU 2458-002-50635131-2003;
- polyacrylamide TU 6-01-1049-92;
Used in the alleged invention emulsion can be prepared as in conditions of industrial production, and immediately prior to use by successive dissolution of the components of the declared quantities.
Give examples of the emulsion.
Example 1 (declared emulsion).
While stirring with a mechanical mixer to 15,0 g hydrochloric acid added to 2.0, , hereinafter referred to as the mixture is injected 40,0 g hydrocarbon solvent mixtures diesel fuel and xylene at a ratio of 85:15, 0,1, methanol, 0.01 g corrosion inhibitor - Dodikor and 42,89 g of water (see table 1, figure 1).
Example 2, 4, 9, 13, 18, 27 prepare as in example 1 without adding primary or secondary alcohols.
Example 3. While stirring with a mechanical agitator to 12.9 g hydrochloric acid added 1.0 g -04, hereinafter referred to as the mixture is injected 12,94, the hydrocarbon solvent - MIA-prom, 4.0 g methanol, 0.01 g corrosion inhibitor - Dodikor, 0.01 g control and viscosity - ES-3 and 69,14 g of water (see table 1 example 3).
Examples 5-8, 10-12, 14-17, 19-26, 28 prepare similarly, changing the kinds of components and their content in the in the declared quantities.
Example 29 (prototype).
In 26,0 g diesel fuel dissolved 0.2 g emulsifier - -9601 at intensive hashing, then in 3 admission impose 7,38 g of hydrochloric acid and stirred for 5 minutes (..1, example 25).
According to the present method of processing of bottom-hole zone of an oil layer of make as follows.
During injection of the first rim aqueous solution of acid into the reservoir is rinsing process equipment and bottomhole formation zone of inorganic salts and iron compounds. Such treatment allows to avoid sedimentation of oil layer of resin, the reaction products of oil with acid in the presence of iron ions. Further pumped emulsion, which is due to the high viscosity of the blocks flushed areas and slows down the speed of reaction to the reservoir rock. The newly injected water solution of acid enters in a zone with low permeability, due to the interaction with the reservoir rock increases the permeability. When further injection of emulsion again, it locks the newly formed high permeability zones, due to the slow reaction with the breed emulsion penetrates deep into formation and, thus, increasing the coverage of the layer effects.
The total volume of emulsion formation treatment is determined proceeding from power of the processed layer, radius processing, porosity and oil saturation factor of the formation according to the following formula: Q=p*R 2 *H*m*KN,
where: Q is the volume of prepared emulsion, m 3 ;
π=3,14;R is the radius of the processing, m;
H - thickness of the processed layer, m;
m - porosity,%;
KN - factor oil saturation layer. Sequentially, alternating treatment is carried out in 1-5 cycles.
Evaluation of the effectiveness of emulsions checked in the laboratory for determination of viscosity, the dissolution rate of marble, clay and checking the stability of emulsions at a temperature of 60°n Research results are summarized in table 1.
To determine the stability of the emulsion in time in the graduated tube tube pour 100 ml emulsion, placed in an incubator at
temperature of 60 C and note the time for complete separation of organic and acid phases.
Viscosity of emulsions determine the rotational viscometer Fann-35 Measurement is carried out at various speeds of rotation of a spindle. It is permitted to change the viscosity of 15-20% within 6 hours. The results of measurements record indicating the brand of the device, the type of spindle rotation speed and temperature. Table 1 shows the values of the viscosity received on the device Fann-35 at room temperature and speed spindle speed 300 rpm, which corresponds to the speed shift 511 -1 .
The rate of dissolution of carbonates (marble) evaluated according to the following procedure. Cube marble square shape weighed accurate within the second digit linear dimensions calculate the volume of a cube and density. The average density of the used marble 2.5 g/cm 3 . Hanging on a thread cube marble lower in the study composition and at regular intervals (10-30 seconds) are removed, washed with water, dried and weighed make up table with the parameters of the relative time of dissolution of the cube and the absolute values of the mass. The method of least squares found from the angle of inclination of a straight on a linear interval dissolution rate (g/s) in this experiment. The absolute value of the dissolution rate (g/m 2 *s) are as the slope of the straight, calculated at the coordinates (m/S), where m is the mass of the cube at regular intervals, S - size calculated by the equation:
S=6(m/p)2/3.
The rate of dissolution of clay evaluated according to the following procedure. Installation of bentonite clay weight of 2 g mixed with 20 g of the proposed acid composition and incubated for 18 hours. Then the solution was filtered through a filter with a known mass, washed with water and dried at room temperature for up to a constant mass and weighed on the filter. The effectiveness of dissolution is calculated by the formula:
E=100*(M-m)/Mo, where:
M is the mass of the initial clay filter after processing, g;
MoE - original mass of clay,,;
m - mass of the filter,
According to the results, shown in table 1 shows that used in the claimed method emulsion has a high viscosity, is more stable. Reducing the speed of dissolution of the reservoir rock increases the permeability of the composition of deep into formation.
To determine the effectiveness of emulsions in its use for formation treatment determine the rate of corrosion and cleaning efficiency. The results are given in table 2.
Table 2 №№Number of table 1
Corrosion rate, g/m 2 *h
Cleaning efficiency, %
1 №1 0,29 83 2 №12 0,22 763 prototype
HCl - 7,38
0,35 45-9601 - 0,2
DT - 26,0
Corrosive activity is checked according to the standard technique on metal plates (steel 3) at room temperature.
Plate size 10*15*3 cleaned, washed in warm water, degrease with acetone or alcohol and dried to a constant weight. The plate hung on a nylon thread in the glass so that when you fill a glass with acid butt plate was about 10 mm below the liquid level. Glass fill acid structure and leave on a fixed time. After a specified time a record is removed from the acid, carefully washed in running water and repeatedly rinsed with hot distilled water. The moisture from the surface of the plate is removed by the filter paper plate and dried to a constant weight.
Corrosion rate is calculated by the formula:
V=g/10 -4 *S*t,
where: V - speed of corrosion, g/m 2 *h;
g weight loss plates as a result of corrosion, g;
S - surface of the plate, m2;
t - the duration of the test, the hour.
Definition of the cleaning efficiency of conduct in dynamic terms, what samples (ASPO) weight 2 g placed in the baskets of stainless steel and wire hung up in the layer prepared in advance of the emulsion in a plastic bottle with a volume of 250 ml Mix the contents of the bottles on a magnetic stirrer at a speed of 400 rpm for 2 hours at room temperature. The incident time specimens are removed, rinse water, air-dried and . efficiency is measured as the ratio of the weight loss sample to its original weight percentage.
When comparing the results show that the proposed emulsion has a high detergency efficiency of ARPD is compared with the prototype, has low corrosion activity
To study the effect of the proposed method on the change of filtration in a porous medium using a model of the reservoir, representing paired metal tube length of 50 cm and 3 cm in diameter varying permeability. As source material for creating porous environment of the use of ground quartz sand in pure water and with the addition of % calcium carbonate.. As a saturating fluids using mineralized water with salt content of 19 g/whether degassed oil diluted with kerosene to 4 .. Formation model saturate water in amount of 2 pore volumes, then spend the ousting of its oil, and then pump the water solution of the acid, and then the emulsion and then replacing it with oil. In another version, after pumping oil spend the ousting of its water is then pumped water solution of acid and claimed emulsion, which also displace water. Change filtration resistance is calculated by the formula:
Q = ( K 1 ( in , n ) - K 2 ( in , n ) ) To 1 ( in , n ) * 100 % , where1,n) and 2 (n) - permeability model for oil and water before and after the injection of a water solution of acid and emulsion, 2 microns .
1. Way of processing of bottom-hole formation zone, including injection into the layer of the emulsion and water solution acid, wherein the first pump the water solution of the acid, and the pumping of water solution of acid and emulsion is carried out in a series-striped mode and in as the use emulsion emulsion of the following composition,% Mas.:
Acid 5,0-40,0, or nonionic, or
cationic surfactant
or a mixture
1,0-10,0Hydrocarbon solvent
5,0-40,0Primary or secondary alcohol
or a mixture
0,1-5,0Corrosion inhibitor
0,01-0,05
Water Rest2. The method according to claim 1, characterized in that the emulsion additionally contains viscosity regulator in the amount of 0.01-6,0 mass%.
3. The method according to claim 1, characterized in aqueous acid is used in 3.0-24,0%concentration.