SU1242000A3 - Method of developing oil pools - Google Patents

Abstract

<P> Process for recovering oil from underground deposits. </ P> <P> The oil is recovered by injecting and displacing into the deposit an aqueous plug containing a water-soluble, substantially linear and high molecular weight polymer obtained by irradiation of an aqueous solution of an aqueous solution. an ethylenically unsaturated monomer and a water-soluble salt under controlled conditions of concentration, radiation intensity, monomer to polymer conversion rate and total radiation dose. </ P> <P> Application to the improvement of oil recovery processes from underground deposits. </ P>

Description

first monomer, inclusive of cationic monomer and 0% lieHOHHoro monomer 2-5.

12A2000

5-100% 2. The method according to p, 1, about tl and h and from 95 up to and with the fact that the mixture of monomers with pH includes 50-80 wt.% Acrylamide and 20-50 wt. % sodium acrylate.

one

The invention of tsnosts to the oil industry, in particular to the flooding of oil reservoirs, with the addition of pumped water along LIMES.

The aim of the invention is to noiui-, the singing of the effectiveness of the extracted oil

 Improvement of the waterflooding of oil-bearing formations was achieved with the use of BJ i, e) OJ5 mainly with a very high molecular weight, very short reaction time and a high degree of conversion (up to 100%). Myo-Nerp, in nolm.r, is a method that includes the irradiation of an aqueous solution of a monomer, with: Oderl and tsego at least one water-, solution-1 y1o salt from class 1 defined; ;; plepnoe below, at T 1; the conditions for conducting the measurement, namely the monomer concentration, the intensity of radiation, the dose of Uch fr n in the monomer conversion. The presence of salt I: an aqueous solution increases the rate of polymerization and, therefore, shortens the reaction time. Salt significantly increases the molecular weight of the resulting BOJniMepa at a JHO set point and revolt my--. polymer and also gives a more linear polymer, as shown by its 1H13 by its value of the Hagns constant, for any given molecular weight. The presence of salts also allows a polymer to be obtained with a very high molecular weight, with the entire monomer evolving into the polymer. The polymers thus obtained better displace oil from the reservoir,

Expressed kenya water soluble nol-- er means at least 90% but. the weight of the polymer is soluble in water during the next test. The polymer is dispersed in water at a weight ratio of 1: 1000 to non-mixed. we will pick up using a magppo mixer with

200 v / mip for 2 hours 100 g of a semi-varietal dispersion solution was filtered through a 200-mesh sieve (opening size 0.063 mm). Then, the sieve was washed with 300 ml of distilled water, 0t-1plt sediment remaining on a spit of 200 mesh, suiili or about a temperature of about 10 to a constant weight. The dried portions, which are an insoluble part of the polymer, should be less than 10% by weight of the KOJH-i4ecTBa polymer contained in 100 g of an aqueous solution.

It is determined by dividing the weight of the dried portion by the weight of the polymer contained in 100 g of solution. The temperature of the water used for this test is 25 C.

Expressed catpop nolimer means a half-measure, an average of 1-100% of a fine polymer cation monomer n of 0-99% of a polymerizing non-ionic monomer,

Expression of ApionG: A polymer means a polymer consisting of

100%

10 15 20 25 30

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4Q

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polymerizable annoiHioi o monomer n of 0-99% polymerizable peiopo-monomer ..;

The expression ampholytic poldashr means a polymer composed of, for example, a monomer carrying polyamide, a polymerizable anionic monomer and a polymerized cationic monomer.

The expression peionic polymer is aa. a polymer containing less than one wt.% or no at all, not containing a polymerization-nom.tn-lCH non-monomer.

Water-soluble salts, which may be used in the proposed method, are salts that are sufficiently Tovuio soluble in the aqueous reaction medium used for neuroveptide or nol; At least 3% by weight of dissolved coheni is based on the total weight of the solution and unable to form free radical accentors

3

under the action of high energy ionizing radiation. In this last class, nitrates nitrites are specifically excluded. In the proposed method, the following salts can be used: potassium sulfate, potassium chloride, potassium fluoride, potassium bisulfate, tribasic potassium phosphate, dibasic potassium phosphate, monobasic potassium phosphate, sodium sulfate, sodium bisulfate, sodium chloride, tribasic sodium phosphate, dibasic sodium phosphate, monobasic sodium phosphate, lithium sulfate, lithium bisulfate, lithium chloride.

ammonium phosphate, dibasic is for sodium chloride, potassium chloride and

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ammonium phosphate, monobasic ammonium phosphate, ammonium fluoride, aluminum sulfate and chloride. Preferred class of salts include sodium chloride, sodium sulfate, sodium bisulfate, potassium chloride, potassium sulfate, potassium bisulfate, - ammonium chloride, sulfate ammonium and ammonium bisulfate. The sodium, potassium, lithium and ammonium salts can be used to polymerize 25 of any unsaturated monomers with ethylene bonds, and the aluminum salts can only be used to polymerize a mixture of monomers containing 5-100% cationic monomer and from 95 to 0% non-monomer .

Not only one salt can be used, but also mixtures thereof. The combination of salts provides a high molecular weight polymer and provides a faster reaction rate than a single salt. Mixtures of the following salts are preferred: potassium chloride, potassium sulfate, dibasic potassium phosphate, monobasic potassium oxide, sodium chloride, sodium sulfate, dibasic sodium phosphate and monobasic sodium phosphate, in which the salts are selected to provide at least 10 wt.% one or more salts having a common anion, and at least 10 wt.% one or more salts, having a second common anion from the first common anion. Especially preferred are mixtures of two or more salts selected from the group comprising sodium chloride, sodium sulfate and dibasic potassium phosphate.

The amount of salt used in the reaction depends on the type of salt and the reaction, as well as on the required molecular weight and reaction rate. The amount of salt used varies from 3% of the total weight of the solution to the point of salt saturation in

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420004

monomer solution at 35 ° C and preferably from 4% to our standard. Particularly preferably, the amount of salt is from about 6% to saturation. Smaller 5 quantities of salt are less effective and for practical purposes do not increase the benefits, as well as large quantities. It has been found that if all other conditions are kept constant, the molecular weight (intrinsic viscosity and linearity of the polymer product) increases with increasing amount of dissolved salt. Preferred concentration

0

five

0 5

ammonium chloride is a concentration from 8% to saturation. The preferred concentration for sodium sulfate, ammonium sulfate and ammonium sulfate is from 4% to saturation.

The radiation-induced polymerization according to the invention is carried out by subjecting the aqueous solution to a salt and at least one unsaturated monomass with ethylene by means of high-energy radiation. The radiation can be corpuscular or electromagnetic in nature and can include accelerated electrons and neutrons. etc., as well as x-rays and gamma rays.

The polymers according to the invention can be obtained from water-soluble monomers corresponding to the formula

40

 C - C - U

R

55

45

50

from a mixture of such monomers or water-soluble mixtures of at least one of such monomers with an ethylenically unsaturated monomer in an amount of up to 50% by weight, selected from the group consisting of vinyl sulfonic acid, an alkali metal salt of vinyl sulfonic acid, diacetone-acrylamide and max mixture. In this formula, R is hydrogen or methyl, and Y,

BUT

- S-S-SZOZM ™ SNZ

 - N

X R,

Rj, X

in which M is hydrogen Hi | N is alkaline, 1-metal or any other type of compound that gives a hydrogen-soluble, fully-merging compound, R ,,, Rj, Ri are alkyl radicals with i - t carbon atoms, and X is an anion. Examples illustrating monomers otBe 1ayuschie this formula include acrylamide, methacrylamide, 2 - akpilamid-2-metIilppopancylrJfokic- lot, acrylic and metakrilovut-e acid and their water-soluble salts, such as salts of alkali metals and AMMO, quaternary salt of dimethyl a1.you can take care of itg shmeta-. ) sr11lat, kiaterpizovna chloride. I BTjbioM, dimethyl sulfate gsi, and, ethyl ethyl;) фfat.,. Preferred compositions of myomeroi include mixtures of acrylamide and sodium acrylate and mixtures of ac-ylamide and quaternary salt / d-methyl-amyl ethyl ethyl acrylate. This invention is also considered by ioMepers, jtojiyHaeMue with i.oles, impregnated mixtures of 1 11tc above ie Bieno, as well as Eo-soluble mixtures of such monomers with other soluble, copolymerizable, unsaturated, ethanically heated zones, with surface mashures, as well as surface zones, as well as surface mashures, as well as surface zones, as well as surface zones, as well as the surface mash- ers, as well as the surface mashines, as well as the surface area of the surface area. , for example, iiiiii1mpda ash, acrylopitrile and maleic acid and water soluble salts of tgaleic acid, as alkaline salts of maleic acid.

With the appropriate choice, combinations of monomerop can be obtained by requiring non-ionic, cationic, anionic or amphibole P-1E polymers. For example, acryl amide gives mainly peioppy polymer quaternary salts Yu-dimethylene or these lakrilata dimetplamipoetil- give katio.pnye methacrylate polymers sepolimery acrylamide with acrylic acid or acrylic kvarterpizovaiiymi salts or metakrihyuvogo AMIPA are aiiopnii or katio2 - respectively pymi , whereas acrylamide terpolymers as with acrylic

ten

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20

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0

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0

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0

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acid and quaternary compounds are ampholytic.

Monomer irradiation ipod. t in a single solution, with a weight of 10-40 wt. preferably 10-30 wt.%. dissolved monomer. At lower monomer concentrations, the product is usually a flowable polymer solution. At concentrations above 15% by weight, the product is a non-flowing gel, using monomer at concentrations below 10% by weight is difficult, and using monomer at concentrations above 40% by weight tends to decrease the amount of salt dissolved in mopomerpom solution. It has been established that while all other conditions are kept constant, the characteristic viscosity of the nonroiep-Ho.ro product increases with an increase in the coprecipitation rate of the monomer.

The intensity of the -radiation has an effect on the molecular weight of the resulting polymer product and, therefore, on the characteristic; zkos gb of its solutions. More efficient molecules are the weight of the products of semi-. at lower intensity intensities, i.e., all other things being equal, the characteristic viscosity of the half-agent exhibits a tendency to increase as the intensity of the applied radiation decreases. On the other hand, the degree of transformation can be reached by the mountain, which could reach the point of weak and strong degree of insolubility, at higher intensities of radiation. A radiation dose rate of at least 1000 rad, preferably 5000 rad at 1. h. To obtain a significantly higher molecular weight of the polymers according to the present invention, Hi-Hce dose rates of 200,000 times per hour are desirable, and to obtain polymers, having the highest possible zpi epi p-molecules. weight, desirable for CR- {more than power for radiation, not exceeding 100,000 times in 1 hour.

It has been established that the total dose of radiation can have an effect on the water solubility of the polymer, a high dose of radiation can transform the polymer obtained and is not soluble in water. In addition, ceteris paribus, the characteristic viscosity of the polymer decreases as the total radiation dose increases. Consequently, the total dose of radiation needs to be selected. The specific dose of radiation depends on the intensity of the irradiated radiation, the monomer concentration, the properties of the monomer used, the salt concentration and the properties of the salt used, and the tax on the characteristic viscosity of the polymer to be obtained. Although a lower dose may be used, it is usually preferred to use} 1 doses of at least 1000 rad. The upper limit of the radiation dose is limited to the formation of substantial amounts of water-insoluble products. However, for most practical purposes, doses up to 3000 rad, preferably up to 15000 rad are used.

Although the polymerization reaction can be hindered when l; a slab degree of conversion to a polymer, the efficiency of the proposed method is better realized when reaching 80-100% conversion and preferably 85-98%. At such high degrees of conversion of the monomer into the polymer, the crude polymerization product is less prone to bond formation during the polymerization of the unreacted monomer after the irradiation stops and can therefore be reliably maintained at room or lower temperatures, or used as such, if it is economically advantageous. Partial polymerization of highly concentrated monomeric solutions containing salt results in polymers with extremely high intrinsic viscosity. However, the crude product of such a polymerization must be immediately turned into a powder, and the unreacted monomer is removed or returned to the next cycle.

The variable values of radiation intensity, total radiation dose, salt concentration and monomer concentration discussed above are interdependent. Although useful polymers can be obtained at all monomer concentrations, radiation intensities, radiation doses and salt concentrations defined within the above limits, all combinations of concentrations

-

and

th

dose and intensity limits may not be used to produce a water soluble high molecular weight polymer. In view of this interdependence of intensity, dose, concentration of salt and monomers, it may be necessary to conduct a small number of experiments in order to obtain a polymer having a desirable water solubility and intrinsic viscosity. However, these experiments can be minimized, since the description contains a number of polymers showing the production of various

15 half-iepoB with different characteristic textures, as well as the effect of intensity, dose, salt concentration and monomer concentration and solubility and characteristic polymer viscosity were considered.

For example, a polymer having an intrinsic viscosity of about 22 deciliters per rparfM B 2 n. a solution of sodium chloride at 25.5 C can

25 to be prepared using the reaction conditions used in Example 2 to produce a polymer having an intrinsic viscosity of 24.2, except that the intensity and / or concentration of the monomer or salt is increased.

The radiation-induced polymerization reaction can be carried out over a rather wide range of pH values. However, it is necessary to avoid very low pH values, since in-ieeT there is a formation of some undesirable insoluble products if the pH is improperly low, especially with acrylamide bases. On the other hand, very high pI values can lead to some hydrolysis and modification of the reacting monomer, which is again valid for acrylamide. Although the specific range depends on the particular combination of monomers to be polymerized and on the particular water-soluble salt used in the reaction, it can be argued that the pI values 2-12 are satisfactory. The preferred pH range for anionic polymers is about 8-11. The preferred pH limit for preparing the cationic polymers is 3-8.

These RP values apply generally to reactions in which water is. soluble salts are salts

thirty

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 EO

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50

potassium, sodium or lithium. If an ammonium salt is used, the pH of the reaction mixture is maintained at an interval of 7-9.

If an ammonium salt is used, then the PX of the reaction medium, D, is set to D within 2-5 to prevent the precipitated salt from precipitating.

The product of the process according to the invention is an aqueous solution of a water-soluble polymer in a flowing fluid or petech-like rubber, Depending on the concentration and intrinsic viscosity of the polymer. The volumetric rate of the polymer solution is increased by i-iepe by. 1 The end of the polymer and its intrinsic viscosity. Third-party polymer ijacTiiop can be run with water; and used and directly, the solution ;. It can be concentrated and can be restored by means of tish: ovle-p in os: osoy (bojj-ie, iaggrimer in sg; de powder., ne-flow P1J gel set should be divided, water should be removed by ordinary i-. drying methods or it is extracted from a water-soluble, volatile organic solvent, crushed on a gel with iOMO1DYO, which has an affinity for the copolymer, for example, methanol.

AiiiioiHibie non-ionic iolimers, io-jr / jeuHbie according to the invention, have an intrinsic viscosity in mei.yyi as 20 ds / g, preferably 23 ds / g. Catalyst polymers have an intrinsic viscosity of at least ds / i. Although the fields, more than irii3Kyio, are intrinsic viscosity, the moss is easily obtained by the method according to the present invention, but no other property is obtained by using this method to obtain such low molecular weight measurements. These are low molecular weight sols. can be ji &amp;r; vO obtained by known spos; both 1 and in the absence of a water-soluble solution. salts. Anionic II peiopic polymers having an intrinsic viscosity of 53 ds / 1 and higher, and cationic polymers with a ge geological characteristic viscosity of 25 ds / 1 iia. or higher, can be obtained by the proposed method.

For the purpose of application, the intrinsic viscosity of non-ionic polymers, cat) polymers and polymers.

0

five

containing anions below 85%, measured in 2 parts of a solution of chloride iatrp at 25.5 ° C, and the characteristic viscosity of polymers having an apioprene content of) is 85 to 100% measured in 2N. caustic soda solution at 25.5 C. If characteristic of the availability of the polymer is measured in water in the absence of 15LI salt of sodium hydroxide, the resultant effect is higher, especially in the case of ionic polymers and polymers having an intrinsic viscosity higher than 10.

The polymers have a constant hag-5 hins 0-0,, 8, preferably 0-0.5. The preferred class of apiopic and non-ionic humimers has a constant of Haggis O - 0.2. The preferred class of cationic polymers in yostoi 1P L Huggins is about 0.1-0.4.

The Huggins constant no-iMepa is a measure of the degree of branching of the vjojHiMepa. For polymers, img-; uix is from one hundred percent molecular weight, but different Huggins constants, lower Huggins constant means a more linear polymer, i.e. the Huggins constant of the polymer and, thus, the number of branching-out can be determined on the graph based on the value of the relative viscosity of the pc1 divided by the concentration as a function of viscosity.

The packet of this curve, divided by the square of the characteristic viscosity, gives the noci-o value of another Hagpas. For the purposes of the present invention, the Huggins constant of the polymers is determined by the method described in: 1 by using a concentration using less than 0.05 ds / g.

The polymers are useful in blends containing water. those. in aqueous polymer solutions for water flooding purposes. More specifically, the polymer is 1-celled in aqueous solutions that do not contain surface active acoustical substances, or contain one or more surface-active additives (i.e., sulphate, preferably petroleum sulphonate) used in conjunction with the surface by the harsh-active compound, (i.e., the growth ester, ester, aldehyde, alcohol, and the like), a hydrocarbon, an inorganic acid, a non-O1:) organic compound, an organic salt, an organic acid,

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, 111

ganich base, organic salt, etc. It is preferable that the other components, if they are present} in a mixture of water1) 1 and fullmer, do not interact with the polymer or by-products of the polymerization process so as not to have a flow and characteristics that regulate the mobility of the polymer.

The polymer can be introduced into the peftenosny layer in various ways, i.e. Before water flooding or intermittently during the water flooding process, or an aqueous solution of the polymer may follow interchange; 1) a medium; i.e., a medium (i.e., slug or liquid displacing oil from the storage tank). In the other, a polymer may be introduced into the oil transporting medium in order to achieve a better adjustment of the flow rate. If it is necessary to improve the profile of the well for injection, then the polymer solution can be introduced before the beginning of the process, the oil is extracted. Volumetric amounts of from 5-150% or more of a bulk volume (BUT) are predictable if the polymer is injected behind the oil displacing medium. The polymer can also be concentrated to spike slug, i.e. up to 10% of bulk volume containing large quantities, for example, up to 2000 hours of nojHiMepa per million. The concentration of the polymer can vary from a high first portion of the aqueous polymer solution to a low concentration in the last portion of the polymer medium to obtain a more economical calculation of mobility control.

If the displacing oil medium is used in combination with an aqueous polymer solution, then it can be miscible, similar to blending. With-and non-intermixing.

A preferred oil transfer medium containing a hydrocarbon, water, a surfactant (preferably obtained by sulphating crude oil or stripped oil), used in conjunction with a surfactant (e.g. alcohol or similar compound) and electrolyte.

The aqueous solution (polymer) may contain additives to impart desired characteristics to the oil recovery process.

42000 2

For example, oxygen scavenging agents, corrosion inhibitors, biocides, antioxidants, viscosity stabilizers, solution stabilizers, and 5 other similar agents can be incorporated into an aqueous polymer solution. Any component can be added to an aqueous polymer solution if it is compatible with the polisher and does not have a negative effect on the flooding of the storage or on the injection of the aqueous polymer solution into the well.

Polymers are especially useful for t5 water-flooding of high-permeability rock storage tanks, i.e. 250 md and more. For example, oil storages with permeability of 1000-2000 mD can be effectively flooded with 20 of these polymers.

Consider the following examples. All parts and percentages are by weight, unless otherwise indicated. The intrinsic viscosity is measured in a 2N, 25% sodium chloride solution at 25 ,.

Example 2, 240 ml of deionized water was added to a 500 ml beaker. In water, 0.6 g ice — 30 acrylic acid, 30 g acrylamide, and 30 g sodium sulfate; The pH of the resulting solution was adjusted to 10.0 with an aqueous solution of sodium hydroxide. The solution was transferred to a vessel for irradiation and flushed with nitrogen for 20 minutes. The solution was irradiated with gamma radiation from an i.-j precision cobalt-B0 for 16 minutes at a radiation dose rate of 20,000 rad / h.

The reaction product was removed from the radiation source and allowed to cool to room temperature. The conversion of the monomer in nojHiMep was 94.7. Part of the gel was extruded and the weighed amount of gel beams added35

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45

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55

l in a beaker containing methanol. The polymer beams were left on methanol in methanol. The beams were then milled in a Vila mill using a sieve with a hole size of 0.635 mm (20 mesh). The crushed product was suspended in methanol, filtered by vacuum filtration, the filter was washed three times with fresh methanol and partially dried on the filter. The semi-dry powder is then dried in a vacuum oven for 24 hours at 36 ° C. The dried polymer powder is dissolved in distilled water and has

13

intrinsic viscosity 14.8 dl / n Haggis constant 0.27. Example 2. A solution containing 210 ml of deionized water, 0.9 g of glacial acrylic acid, 45 g of acrnlamide and 45 g of sodium bicarbonate was used in the same way as in Example 3, pH of the solution was adjusted to

before

, 6 hydrochloric acid solution

on three . The solution was placed in a reactor, rinsed with nitrogen for 20 minutes, and irradiated with gamma radiation from a cobalt-BO source for 10 minutes at a radiation dose rate of 2000 rad / h. Then the product was cooled to room temperature. The polymerization product was non-flowable gelatrice, and the i-ionobscpa 3 polymer formulation was 96.0%. Both the rubber-like gel and the porosity obtained from it are soluble in distilled water. (Golimer characteristic viscosity 24.2 d, l / g and Haggms constant, O.J Q.,

PR m and me 3. 10 fuptoz (4536 g) ;; 10, in pt ly (283.5 g) sodium hydroxide, II ymi.py (311.85 g) glacial acid, 1 pound 3.25 ounces (545.74 g) patty sulphate and 2 pounds 1.5 ounces (949.5 g) acrylamide for - i py; ajni and plastic bottle with a capacity of 5 gallons (22.7 liters) for processing. The pH of the solution was set at 9.5 with the nominal sodium hydroxide. Then, the monomer solution was irradiated for 16 minutes by raMiMa radiation from a cobalt-BS source at a dose rate of 2000 rad / h. The degree of conversion of the monomer into the wateen-spol is 83.4%. The reagent product is a fully water soluble rubbery g spruce. The polymer obtained is polymer soluble in water and has an intrinsic viscosity of 29.3 dl / g and a Huggins constant of 0.15

P and measures 4. An aqueous solution was prepared containing n 8 pounds and 3 ounces (3705 g) of deionized water, 8 ounces (226.8 g) of sodium hydroxide, 14.5 ounces (411.1 g) of ice acrylic acid, 2 pounds 12 ounces (1247.2 g) of acrylamide n pound 3.25 ounces (546.1 g) of anhydrous sodium sulfate. The ERP was set equal to 9.5 with concentrated sodium hydroxide and in accordance with the procedure described in Example 3. Then the solution was placed in and

14

washed

nitrogen for 20 min. The solution was irradiated for 6.5 min-gamma radiation from a cobalt-60 source at the radiation intensity

20,000 rad / h The resulting gel was removed from the irradiation {and allowed to cool to room temperature. The conversion of monomer to polymer reached about 47% by weight in the calculation of pa

total monomer weight originally

present in solution. A part of the newly-irradiated gel was extruded, and the weighed amount of gel beams otdeltsdgshy in excess of the metafol. Hardened beams were ground in a Bile mill using a 20 mesh sieve (0.635 g-s hole size). Grind - jpeg product cycpe Jp in me- type alcohol, the extract was filtered

and dried in vacuum for 24 hours at 36 ° C. The received polymer was dissolved in 3MIM, B distilled water and had an intrinsic viscosity of 40.0 dl / g and a constant Huggpps of 0.0.

II p and me R 5. A solution containing 100 ml of deionized water, 150 ml of a 40% aqueous solution of dimethyl sulg. The military quaternary salt dimethylamide, ethyl acetate, 60 g of chlorine sodium and 20 g of acrylamide were irradiated with gum-l from the teachings of a source of cobalt 60 similar to that described in example i. The solution was irradiated for 14 minutes at a MOfflfiocTn dose of 20,000 rad / h. The resulting product is a non-flowing, viscous gel. The rubbery gel was then removed from the irradiation zone and cooled to room temperature. The conversion of monomer to polsher was 83.2%. The polymer is soluble in water, and its intrinsic viscosity is 18.7 dl / g. P noCTOHiniyio Huggins 0.06.

II p and mery 6-42. A specific amount of monomer and salt is added to a reactor containing the specified amounts of deio-ozipirovapnaya water. The pI of the solution was set to a specific value using 10 n sodium hydroxide solution. MbiBajn solution; nitrogen in the gaseous state;. for 20 mpn, p the reaction vessel was closed. The sample was irradiated with gamma-rays from a source of cobalt-60 inter-activity at 2000 rad / h until it was formed, and ne received a certain total dose of radiation. Then about} aztsi removed from camera about

five

radiation for further processing. The characteristic viscosity and Huggins constant were determined by standard methods. The degree of conversion of the monomer to the polymer was determined by weighing the part of the reaction product that was extracted with methanol to precipitate the polymer, drying the polymer under vacuum to constant weight. The weight of the dry polymer divided by the theoretical weight of the product, which would have been obtained if 100% monomer conversion was achieved, gives the percentage of monomer converted to polymer. The results obtained in examples 6-42, are presented in table. one..

Example 43. 325 g of deiotic water were added to a 500 ml bottle. 11.5 g of sodium hydroxide, 20.7 g of glacial acrylic acid, 63.0 g of acrylamide, 20 g of sodium sulfate, and 60 g of sodium chloride were dissolved in water. The pM of the resulting solution was adjusted to 9.5 with aqueous Hbnv sodium hydroxide solution. The solution was then placed in a vessel for irradiation and washed with nitrogen for 20 minutes. The solution was irradiated with J Siina with cobalt-60 radiation for 10 minutes at a radiation dose rate); 20,000 rad / h The reaction product was removed from the irradiation source and left; for cooling to room temperature. The resulting product was an aqueous gel of a water-soluble high molecular weight polymer. The polymer had a higher molecular weight than the weight of the polymer, which was clearly obtained under the same irradiation conditions and the comparable numbers of only one salt.

Example 44. 100 ml of deionized water was poured into a 500 ml beaker. 150 ml of a 40% aqueous solution of dimethyl sulfate quaternary salt of dimethylamino ethyl acrylate, 20 g of acryl amide and 60 g of sodium chloride were dissolved in water. The RP of the resulting solution was set at 3 by adding a small amount of a dilute solution of sulfuric acid.

The final solution was poured over the vessel for irradiation and, in 20 min, washed with previously purified nitrogen at a flow rate of 3 l / min. After washing, the solution was irradiated with gamma radiation from cobalt-60 for 14 minutes at an intensity of

42,000. sixteen

radiation 20,000 rad / h. The crude polymerization product was removed from the source. radiation at the end of the 14-minute irradiation period, and the product was a completely water-soluble, gentle gel. The gentle gel was carefully weighed and added to a beaker containing about five times the amount of acetone OT

10 gel weights The gel was left in acetone overnight for curing. The cured gel is spun on a Vila mill using a 20 mesh sieve (0.635 mm orifice size). The ground product was agitated in acetone, filtered by vacuum filtration, and washed on a filter. fresh acetone and partially dried on a filter. The semi-dry powder amount P € o was transferred to

20 wide-necked jars and dried in a vacuum 1 st furnace for 24 hours at 36 C.

The percentage of solids in the vacuum-dried Powder was determined by the daytime portion of the powder in the convection oven before reaching the constancy c., After which the amount of sodium chloride was calculated by the amount in the vacuum-dried por g. Monomer conversion rate

ed in the polymer was calculated according to the equation

Percent% Dry powder weight is weight of sodium chloride. (100)

The theoretical amount of polymer per 100% conversion

Based on the 1P1 and the above equation, the calculated 1a is the degree of monomer conversion to the polymer was 83.2%.

Both the gel product and the vacuum-dried product were tested for water solubility in distilled water, and their water solubility was established.

The intrinsic viscosity of the dry polymer, measured in 2N. sodium chloride at 25 ° C was 18.7 dl / g.

Constant Huggins 1H1a for polymer is calculated from the equation below and is 0.06

PZR

WITH

to

 WITH

7

where K is the Huggins constant,

P5P - calculated relative

viscosity change in 2 and.

sodium chloride at Hp - intrinsic viscosity

in 2 n. sodium chloride at

25 s; cj is the concentration of iolymer in

solution (g / dl).

Example 45. A solution containing 150 ml of deionized water, 150 ml of a 40% aqueous solution of dimethylaminoethyl acrylate dimethyl sulfate quaternary salt, and 20 g of stirring acrylamide and adjusted to a pH of 3 with a solution of sulfuric acid. The solution was rinsed with nitrogen for 20 minutes and irradiated with 16 milfi dose rates of 20,000 rad / h. As a result, polymers were obtained; the gel, which is quantified, according to the procedure described in Example 1. The conversion of the monomer into a polymer was 83.6%, the intrinsic viscosity was 10.1 dl / g, and the constant Chag was determined to be 0.25.

Example 46-63. Aqueous plants of bopti monomers were prepared with a monomer content in 1G1 by weight: OCe 1ta, indicated in Table 1. RP i; acTUopoB I.IOHo: The substrates were set aside with a solution of caustic soda. Ka; ay monitors were loaded and pea1C1; a clear vessel was irradiated; Kovoj-Mii was washed with gaseous gases — 20 minutes; II vessel was closed; llononcpui .: the solution was irradiated with r, 1-1–1, the radiation of the source of cobalt-60 p. / h during the time specified in Table 2. The irradiation was stopped, the ofipaLUiu was removed from the irradiation flask for further processing in accordance with the general procedure described in Example 44. IJpe.discision, characteristic and the Huggins constant was determined for each sample using the method Yes, described in example 44. The results obtained in the implementation of examples 46-63 are presented in the table. 2

Examples 64-75. The following examples are given to compare the intrinsic viscosity of polymers produced by radiation-induced polymerization of solutions in the presence or absence of salt with

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 chemically initiated polymerization of monomer solutions in the presence or absence of STVI1. Radiation polymerization reactions are carried out according to the procedure described for examples 44-64. Chemically initiated polymerization reactions (Examples 68, 69,70) are carried out according to the following method, with the exception of time and scale:

340 ml of deionized water was poured into a 1000 ml chemical beaker. 7.7 g of sodium hydroxide granules were dissolved in water. To the resulting sodium hydroxide solution, 13.8 g of glacial acrylic acid was added. 42 g of acrylamide was added to the resulting sodium acrylate solution. The solution was stirred until 1 acrylamide was completely dissolved. RP

30 of the resulting clear solution was adjusted to 9.6 with sodium hydroxide solution. The solution was transferred to a conical type glass reactor with a diameter of about 4 inches.

25 (10.16 cm). The boiler was closed with a special krppka, with 3 openings with spabzhein - pi. A thermometer was introduced through the central opening of the boiler lid into the solution, and the solution was passed with gaseous azo 30 TOG I for 20 i-nia at a current speed of 5 j.f / MUH through the side openings K1) Ly. At the end of the washing, the holes were closed and the boiler was heated to reach a temperature solution of OO C. At this time, 1 ml of 2% - Ny solution of potassium peroxydisulfate was added to the boiler and heating was stopped. After 30 MPa reaction temperature

35

the reaction mixture reached 76.8 C.

At this time, the reaction vessel was cooled with cold water to room temperature. The reaction mixture was a soft gel-type material, completely soluble in. water. 100 g of a gentle gel was treated, y-, or methanol according to the method of polymer processing described in Example 44 and the percentage conversion of the monomer into a polymer was evaluated.

Examples 73,74 and 73 were performed as described in example 68 of the general method.,. The results obtained during the polymerization reaction of examples 64-75 are given in table. 3. P p and MO p 76. Copolymer A was obtained according to the described technology. Oi had a characteristic in e-i; ooTb 28 dl / g and a polymer activity of 70%. Copolymer.B was prepared

According to the method described in US Pat. No. 3,841,401, the intrinsic viscosity is 29 dl / g and the activity is 88%. Both polymers were obtained from monomer concentrations: 40% acrylate patrn and 60% acrylamide, 6 inch (15.24 cm) star-shaped sandstone cores (obtained from the Heperi, Robinson, PCs, Illinois, USA) were placed in a tertiary state ( ) at the first flooding with water containing about 5900 parts of dissolved solids (PTB) per million hours. water, then flooded with crude oil with a viscosity of -7 cP until it reaches the minimum saturation with water, then flooded with water containing about 5,900 hours. RRP per million, parts of water until it is reduced.

by oil. These cores were then flooded with 7% of the bulk volume (MO) of identical micellar solutions, followed by flooding with an aqueous solution of the polymer, containing 500 hours of polymer per million parts of water, followed by. 53% of an aqueous polymer solution containing 258 parts of polymer per million was flooded, and this was accompanied by a 30% BUT of an aqueous solution of a polymer containing 50 hours of polymer per million hours. water, followed by a blast of 50% on the external section: water. All water used in aqueous solutions and water used in npimepax I and 3 contained 15,554 parts of dissolved solids per million and 196 parts of calcium cations and 89 parts of magnesium cations per million parts of water, whereas. the water used in examples 2 and 4 contained 16250 parts of solids dissolved in it per million parts of water and did not contain calcium and magnesium cations.

The results of the flooding of the cores are given in table. four.

Example 77. Polymer A was compared with known polymers. .Polymer dow. Pusher 7lDO (partially hydrolyzed, high-molecular; the street polyacrylamide, which has a characteristic

viscosity 15 dl / g about 30% of acrylamide groups are hydrolyzed, supplied by chemical company Dow, Miland, pcs. Michigan (USA), polymer Nalco

586 (a copolymer of 30% sodium acrylate and 70% acrylamide, having an intrinsic viscosity of 17 dl / g, is manufactured by chemical company Napco, Chicago, Illinois (USA) and Calzan UF polymer (a polysaccharide polymer produced by Kelko, 75 End of Even, Clara, NJ).

The cores were placed in a tertiary period, then flooded with 6% of the bulk volume of the crystalline solution, followed by flooding with 20% of the bulk volume of the polymer’s aqueous solution containing the polymer concentrations listed in Table 5, followed by the flooding of the 50% bulk volume of the polymer containing the indicated in tab. 5 concentration and this in turn

accompanied by filling with water to move the previously injected medium through the core. The water used contained 5605 parts of dissolved solids, 128 parts of cations

 calcium and 96 parts of magnesium cations

pas million water Tab. 5 shows the permeability and porosity of the icepop and the results of flooding.

Although the invention has been described with reference to specific reaction conditions, reagents, flooding conditions, etc., however, it is clear that conditions may be different.

and equivalent conditions in relation to the described.

20.0 21.0 76.7 2.8 0.16

16,088,629,30,13

20,077,517,20,22

17.078.52, O0.18

15,083, .425,00,14

8,048,533,50,00

31,090,321,80,22

11,087,231,, 04

16,064,830,60,14

6,547,240,00,00

 32.5 92.0 21.8 0.19 12.0 90.6 28.7 0.07

24.5 93.0 21.3 0.19 12.0 93.5 28.3 0,. () 7

20.0 16,086,519,80,19

. 12,092,525,00,10

13,010023,50,12

10,087,026,20,12

64 70% acrylate

Table 3

j Table A

Editor A. Lezhnin

Compiled by I. Lopakova Tehred I. Popovich

Order 3618/60 Circulation 548

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Proofreader S. Shekmar

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Claims (1)

1. METHOD FOR DEVELOPING OIL DEPOSITS by flooding an aqueous polymer solution, characterized in that, in order to increase the efficiency of oil recovery, use a polymer obtained by ionizing irradiation of an aqueous solution having a pH of 2-12 and containing 10- 40 wt.% Ethylenically unsaturated monomer of the formula I about H ₂ C = CCY (I) R • where R is hydrogen or methyl; Y is the group NH _X , - OM, or _n + '- OC ^ C — N— · X or —NC (CH ₃ ) 2-CSO ₃ M where M is hydrogen; HqN ⁺ - an alkali metal or any other polymerizable water-soluble compound forming cations; R ^, R ₂ , Rj, C4 -Ctfalkyl; X is an anion, or a mixture of monomers corresponding to formula (I), or a mixture of at least one of the monomers of formula (I) with a monomer with an unsaturated ethylene: bond in an amount of up to 50 wt.%, Selected from the group comprising vinyl sulfonic acid , an alkali metal salt of vinyl sulfonic acid, diacetone acrylamide. and containing at least 3 wt.% of a salt selected from the groups potassium sulfate, potassium chloride, potassium fluoride, potassium bisulfate, tribasic potassium phosphate, dibasic potassium phosphate, monobasic potassium phosphate, sodium sulfate, encore fata sodium chloride, sodium, tribasic sodium phosphate, dibasic sodium phosphate, monobasic sodium phosphate, lithium sulfate, lithium hydrogen sulfate, lithium chloride, ammonium sulfate, ammonium bisulfate, ammonium chloride. . tribasic ammonium phosphate, dibasic ammonium phosphate, monobasic ammonium phosphate, ammonium fluoride, aluminum sulfate, aluminum chloride, and mixtures thereof, and ionizing irradiation is carried out with an intensity of 1000-200000 rad per 1 hour to a total dose of 1000 000 000 rad, and if the salts are selected from groups of aluminum sulfate, aluminum chloride and mixtures thereof, the polymer solution consists of ethylenically unsaturated SU < _and , 1242000> GO monomer including 5-100% 2. The method according to claim 1, about t l and h but - cationic monomer and from 95 to 10 SH 1-1 th with i the fact that mixture monomers 0% ι non-ionic monomer with pH  includes 50- May 80,% acrylamide and 2-5 20-50 Of May. % acrylate sodium J