Additives for extraction of oil from oil formations

FIELD: oil and gas industry.

SUBSTANCE: method for extraction of oil from carbonate formations involves dilution in water or salt solution (in quantity of 0.01-20%) of quarternary polyamines of the specified formula, where n≥1; R1 represents H, CH3, CH2CH3, CnH2n+1; R2 represents H2CHOHCH2, CH2, CH2CH=CH2, R3 represents CH3, CH2CH3, CnH2n+1; R4 represents CH2, CH2CH=CH3; and if R2 and R4 represent allyl groups, then altogether they can form aliphatic cyclic structures; ratio between atoms of carbon and nitrogen (C/N) is at the interval of 2 to 30, and further introduction to the well.

EFFECT: increasing oil extraction degree.

15 cl, 30 ex, 4 tbl, 5 dwg

 

The present invention relates to the use of additives capable of increasing the degree of extraction of oil from oil reservoirs, preferably carbonate oil reservoirs with low permeability.

More precisely, the invention relates to the use of additives capable of modifying the wettability of rocks with wet oil wetted with water without lowering thus the interfacial tension (the term "wet oil" refers to the surface, essentially soaked in oil, and Vice versa, the term "wet water" refers to the surface, mostly moistened with water).

Approximately half of all known deposits in the world belongs to the carbonate type. The specific nature of the layers of these deposits along with the fact that they usually have a crack, low permeability and moistened with oil, leads to the difficulty of extracting oil: extraction rate is usually much lower than 30%.

This is because in the extraction process gets only crude oil, located in the cracks, while the oil contained within the skeleton of the breed, is held in the negative capillary pressure due to the fact that the porous skeleton dipped in oil.

That carbonate reservoirs mainly moistened with water, is the result of years of physico-chemical interactions between Ugledar the DAMI and rock surface, and in particular interactions between the carboxyl components present in crude oil, which can be expressed quantitatively by means of the acid number of oil, and the surface of the breed. From this consideration it follows that it is possible to restore the surface condition prior to initial conditions when the surface is moistened with water, just helped release of these components.

Since the mid-nineties, many of the laboratory directed research on search additives, which when added to the input water is able to increase oil recovery from carbonate reservoirs.

Still, methods have been developed based on the use of surface-active agents or polymeric surface-active agents, some of which have proven their ability to pay rock wettability, so that the captured oil can spontaneously be released.

However, one of the characteristics of surface-active agents is that they reduce the interfacial tension oil-water, and is in the process of oil displacement by water leads to a significant reduction of capillary pressure, the driving force of the phenomenon.

This leads to the slow kinetics of the displacement, which causes a significant reduction in industrial use of these additives.

Even if this issue and the prize is Ana specialists in this field, still not found the solution.

Now discovered that a particular group of additives capable of modifying the wettability of rocks without reducing the interfacial tension of water-oil unlike surface-active agents.

This creates a situation conducive to the inversion of the capillary pressure, while its absolute value remains high, while seeking spontaneous release of oil with a higher degree of extraction of oil than could be obtained so far.

Therefore, such values as interfacial tension and wettability, are treated as independent variables, whereas in the adopted still approach, which implied the use of surface-active substances, these two values was joined.

This aspect is of particular importance, taking into account the fact that in recent years many laboratories have focused on the search for additives that can improve oil recovery in carbonate oil reservoirs, and found no additives, which do not lower the interfacial surface.

Taking this into consideration, the present invention is the use of Quaternary polyamines of formulas (I) to extract the oil from the reservoir

where n≥1,

R1is own the th H, CH3CH2CH3CnH2n+1,

R2represents H2CHOHCH2CH2CH2CH=CH2,

R3represents CH3CH2CH3CnH2n+1,

R4represents CH3CH2CH=CH2.

If R2and R4are allyl groups, they together may form an aliphatic cyclic structure, the ratio between the atoms of carbon and nitrogen (C/N) is in the range from 2 to 30.

The ratio between the atoms of carbon and nitrogen (C/N) is in the range from 2 to 20, and more preferably from 2 to 12.

n preferably ≥2.

It is proved that the application of the proposed invention the polyamine is especially effective for oil recovery from carbonate reservoirs.

Offer polyamine not have surface-active properties, they are soluble in water and is particularly soluble in salt solutions.

Preferred cationic polyamine is polyamine having formula II, III or IV, is presented below:

Patterns III and IV represent a polymer obtained by cyclization of chloride of diallyldimethylammonium, and in this case, R1and R3represent CH3while R2and R4represent the keys two allyl groups, which cyclists during polymerization.

In particular, the best results were obtained using chloride of polydiallyldimethyl (poly-DADMAC, III/IV), which is commercially available under the trade name FLOC 572 (3F Chimica"). This substance and used in the examples below.

For the purposes of the present invention can also conveniently be used copolymers of Quaternary polyamines, for example polyamine/polyacrylamides; polyamine/polyamides, polyamine/oxides and additives obtained by quaternization of the reaction product of manniche obtained by the interaction of formaldehyde, polyacrylamide and a secondary amine.

In all these cases, the molar proportion of the copolymer should be less than 30%, preferably below 20%.

Proposed in the invention polyamine (or copolymers) do not possess surface-active properties, i.e. they do not change the interfacial tension of crude oil. In particular, they do not lower the interfacial tension of crude oil to values less than 2 mn/m, They are preferably supported interfacial tension of oil greater than 5 mn/m, and still more preferably greater than 10 mn/m

Offer polyamine have significantly improved with respect to the kinetics of release of oil characteristics compared to the characteristics of cationic surface-active agents is s, typically used for such applications.

Another object of the present invention is also a method of increasing the degree of extraction of oil from the reservoir, which includes the preparation of an aqueous or saline Quaternary polyamines in concentrations in the range of from 0.01% to 20% and the subsequent introduction into the well.

It is preferable to use polyamine in concentrations in the range of from 0.01% to 10%, and still more preferably from 0.05% to 5%.

The application of the proposed polyamines as additives in the process of extraction of oil captured by the skeleton of the breed, component layers, preferably a carbonate, an inversion wettability rocks without changing the interfacial tension. Therefore, the kinetics of displacement, which usually violate additives that reduce interfacial tension, is accelerated and becomes compatible with the time of placing the water.

Moreover, the absence of surface-active properties of these polymers reduces possible problems associated with the formation of foams and emulsions, which may occur in certain stages of production (e.g. separators), if the use of surface-active agents.

Proposed in the invention additives were selected using two tests.

The first is a qualitative assessment of the efficiency of removal of oil from carbonate is orosco, while the second is associated with the quantitative assessment of the ability of the investigated additives to displace the oil.

These two simple and effective way to conduct a quick test of additives, suitable for oil removal.

The first method is based on the ability of additives to remove oil and makes it easy to conduct a preliminary assessment and selection of the studied additives.

In particular, this method includes pre-processing of carbonate powder crude oil and the subsequent dispersion of a pre-processed powder additives in solutions with a certain concentration.

The effectiveness of pre-treatment depends on the type of crude oil (in particular, from its acid number), temperature and duration. Conditions of the test involve the use of crude oil with an acid number >of 0.25, the temperature is in the range from 60 to 90°C, and the length of the pre-processing is >10 days.

It is preferable to work with a crude oil having an acid number of >1.0 at a temperature of 80°C and the duration of treatment is 10 days.

The effectiveness of pre-processing is the ability to reproduce highly moistened with oil of carbonate rock.

For correct interpretation of the data is necessary to use crude oil interfacial tension of >10, e is th not contaminated by surface-active agents, added during the production process.

The second method allows to quantify the ability to displace oil, the characteristics of the additives that have demonstrated positive results in pre-test 1.

The test is carried out using layers of rock, which moisten with oil by appropriate pre-processing crude oil, and evaluating changes in their masses (using high-precision scales, connected to the computer) some time after immersion in the test solution additives.

Pre-processing is again carried out using crude oil with a higher acid number (at least above 0,25), while maintaining the breed in oil for at least weeks at a temperature of >60°C. When the sequential use of two methods can be quickly, simply and efficiently carry out the selection of numerous additives.

Were evaluated four types of oil for tests on endurance carbonate powders and drives breed. Two types, denoted as A and B, were obtained from a field in southern Italy (both were taken at the wellhead). The other two species, marked C and D were taken from a field in Northern Italy. Of the last two types of crude oil sample C was taken at the wellhead, while the D - volume of oil. For comparison purposes as model pleva is Orada used heptane.

Table 1 shows the acid number and interfacial tension of four samples of oil used in our study.

The best results were obtained with the use of oil coming from the fields to the North of Italy. The best characteristics of this oil due to the high value of the acid number associated with a high value of interfacial tension (typical for crude oil is not contaminated by surface-active agents).

The petroleum sample D was actually proven to be defective, as it seems, turned out to be contaminated by surface-active agents (as evidenced by the low value of interfacial tension), probably introduced into the volume of the oil (as demulsifiers, corrosion inhibitors, etc. during the process of oil separation. In this respect it should be remembered that the presence of surface-active agents added to the used crude oil, may jeopardize the investigation of wettability.

In those cases, when it comes to powders, were used carbonates with different composition and particle size (marble, Portland cement, calcium carbonate and microdol).

As for the additives were investigated surface-active agents, water-soluble, representing a diverse group of industrial surface-active agents (ionic, non-ionic and polim rnie). In particular, sodium dodecyl sulphate (LTOs) and dioctylsulfosuccinate sodium (DOSN) were analyzed as anionic surface-active agents; bromide of dodecyltrimethylammonium (DTAB) and bromide of cetyltrimethylammonium (CTAB) as a cationic surface-active agents; various ethoxylates and some polyglucoside (PGA) as a nonionic surface-active agents. Atlox 4912 (Uniqema) was selected as the polymeric surface active agent.

The investigated polymers (not possessing surface activity) was a water-soluble industrial plastics company "3F Chimica" with different molecular weight and different charges (cationic and anionic), as well as comparisons were analysed by two cationic polymer company "floger on".

EXAMPLES

The results of the tests are presented in tables 2 and 3. The tests were conducted in accordance with the procedures described in test 1 and test 2, presented in detail below.

In particular, the purpose of test 1 was to conduct a quick preliminary qualitative test of the investigated additives, and then better assess the characteristics of the most interesting products using quantitative analysis carried out with the help of the test 2. As the latter test is more time-consuming and laborious, it was conducted only for the most p is Chadasha additives.

Test 1. Qualitative assessment of additives on the efficiency of removal of crude oil from pre-treated powders. The test was performed in two phases.

A. Excerpt carbonate powder.

The test consists of pre-treatment powder for 10 days at a constant temperature (80°C) in oil C. the Extract was performed in a rotating steel cylinders.

After exposure, the samples were filtered on filter paper and left to dry. Seasoned powder (1) was weighed (4 g) in test tubes, and aqueous solutions (12 g) of the investigated additives were added thereto in a concentration of 0.1% (controlled pH of all tested solutions).

The samples were mixed using a vortex for 2 minutes. Was visually observed the secretion of oil.

Test 2. The test oil.

Drives breed "Leccese" pre-processed in a petroleum sample C for 1 week at 80°C. the Breed was immersed in oil under vacuum, to make sure it is completely soaked with crude oil.

Rock samples were hung in a basket on a connected computer scales.

Analysis was performed by immersing drenched in oil rocks "Leccese" in aqueous solution studied additives and registration of the change of their weight over time.

Measurement of interfacial tension

Measurement of interfacial tension were dsproducts, that was demonstrated during the tests, good results, in order to assess their surface-active properties.

The measurements were carried out in three different tools depending on the magnitude of the measured interfacial tension. In the case of low interfacial tension measurement was performed using the method of rotating drops ("Physics Data"), whereas the values of interfacial tension is higher than 2 mn/m was used tensiometer ("Kruss") and the way the hanging drops ("Physics Data").

Examples 1-14

In accordance with the procedure described for test 1, was assessed by the ability of the compounds listed in table 2, remove the oil.

Table 2 shows the results associated with the main investigated by surface-active agents in comparison with water, sodium carbonate solution, the chloride of ethylendiamine (and the corresponding basis) as representative of a simple nitrogen-containing molecules with the Quaternary nitrogen atom not being part of the polymer.

Figure 2 shows a photograph reflecting the allocation of oil for some of the used surface-active agents: DOSSN (dioctylsulfosuccinate sodium), LTO (sodium dodecyl sulfate), DTAB (bromide of dodecyltrimethylammonium), CTAB (bromide, cetyltrimethylammonium).

As you can see, only two cationic surface-active agent (DTAB and features the CTAB) is capable of removing the oil.

The results show that under conditions of strong absorption of oil by breed (under these conditions, which were created in the test trials) mechanisms involved in the removal of oil, is not the reduction of interfacial tension or solubilization of oil inside the micelles, and the positive charge of the cationic surface-active agents. In this regard, it should be remembered that recently, it was shown that cationic surface-active agents give the opportunity to better allocate oil in comparison with other groups of surface-active agents. It is believed that the cationic surface-active agent capable of forming a complex with the acidic components absorbed by breed, and remove them from it, and thus again to restore the water-wetted surface through the mechanism of formation of ion pairs.

Examples 15-28

In accordance with the procedure described for test 1, evaluated the ability of polymer compounds, characterized by charge and molecular weight, to remove the oil.

Analyzed several compounds 3F Chimica ("Floc") in comparison with the two polymers floger on" (DP-PT, DP-FO). Cationic polymers are usually used as deflocculants for water purification. Characteristics of the investigated products are shown in table 3; studied were polyacrylamides, cationic polyamine (and chloride polymer polydiallyldimethyl mania, briefly called poly-DADMAC).

Table 3 contains information on the tested compounds and the results of the test.

As can be seen from table 3, only a few of cationic polyamines capable of removing crude oil, in particular a polymer, designated as Floc 572 (chloride of polydimethyldiallylammonium, figure 3), which demonstrated excellent test results.

The photograph in figure 3 demonstrates the ability to remove oil from Floc 572 compared with surface-active agents. The picture also shows that the cationic polymer DP/PT does not work.

The photograph in figure 4 refers to the comparison between the solutions of CTAB and polymer Floc 572 at 0.1%. The picture shows the different characteristics of these two additives, which manifests itself in various interfacial tension of their aqueous solutions: surface-active agent actually dissolves oil inside the micelles, which causes formation of a dark solution, and the polymer, on the contrary, clearly separates the oil.

Table 4 shows the interfacial tension Floc 572 compared to CTAB. You can see that the polymer does not possess surface-active properties, in fact, it slightly lowers water surface tension and interfacial tension with heptane and crude oil A.

Test 2 was performed with both additives in order to quantify the characteristics of the Floc 572 in than the AI with a cationic surface-active agent CTAB.

Example 29

In accordance with the procedure described for test 2, evaluated the ability of CTAB and Floe 572 to displace the oil.

The test results shown in figure 5. On the y-axis of deferred measurement of weight in relation to the original dry weight. You can see that when submerged rocks in the water determine the weak reducing its weight, and this means that the water removes excess oil. Conversely, as the surface-active agent and the polymer solution causes an increase in the relative weight, and if the first gives only a minor effect, the second causes a change of 2.8%.

Example 30

In accordance with the procedure described for test 2, evaluated the ability of a solution Floc 572 2% KCl to displace oil in comparison with the same salt solution containing 0.1% CTAB.

The obtained results are similar to results obtained in example 29. Test again showed that the polymer is more effective to replace oil, and confirmed that a higher capillary pressure, due to the high interfacial tension, facilitates the displacement of oil from the rock, which leads to increased recovery of oil.

Table 1
Interfacial tension demineralized water/oil and an acid number of studies is avannah types of crude oil
Types of crude oilThe origin of oilInterfacial tension (25°C)Acid number (mg/g) KOH
A (35°API*)From wells in southern Italy160,17
B (32°API)From wells in southern Italya 21.50,23
DFrom a well in Northern Italy0,50,54
C (19°API)From a well in Northern Italy18 (at 40°C)0,78
* on a scale of API (American petroleum Institute)

Table 2
The ability of the main surface-active agents to remove oil compared with water, sodium carbonate solution and the chloride of ethylendiamine
ExamplesAn aqueous solutionThe results of Test 1 pHγi(mn/m) crude oilγi(mn/m) heptane
Example 1Demineralized waterno6a 21.548,3
Example 2Na2CO30,1%easy removal11,325,648
Example 3Chloride of ethylendiamineno5,1
Example 4The Ethylenediamine 0,1%no10,9
Example 5LTOs 0,1%no4,28
Example 6DOESN 0,1%no6,9 8,914
Example 8CTAB 0,1%Yes6,80,292,73
Example 9CTAB 0,001%no6,81714
Example 11CTAB 0.1% in Na2CO3Yes10,90,01
Example 12TAB 0,1%Yes6,80,251,24
Example 13Glucopon 215 0,1%no92,5
Example 14Tween 85 0,1%no7,71,3

Table is 3
The ability of polymer compounds, differing in charge and molecular weight, to remove oil
Examples 15-28An aqueous solutionpHThe type and density of chargeMolecular weightThe results of the test 1
Example 15DP-FO 1% polyacrylamide4,87charge +no
Example 16DP/PT 2130 polyacrylamide7,2charge +no
Example 17FLOC 572 chloride of polydimethyldiallylammonium5,6charge + averageaverageYes
Example 18FLOC 575 polyamine5,41charge + highlowno
the example 19 FLOC 576 polyamine4,4charge + highaverageslightly
Example 20SED AM 482 polyamine5,01lowslightly
Example 21Floc 412 polymethylene polyamineof 4.45no
Example 22Sedifloc 435 polyacrylamide4,27charge + lowlowno
Example 23Sedifloc 438 With polyacrylamide4,12charge + highlowno
Example 24FLOC 1403 With polyacrylamideto 4.68charge + lowaverageno
Example 25FLOC 1408 With polyacrylamide5,63charge + averageaverageno
Example 26FLOC 1405 polyacrylamide5,14charge + highaverageno
Example 27Sedifloc 710 polyacrylamide6,5charge - lowhighno
Example 28Sedifloc 740 polyacrylamide7,1charge - highhighno

Table 4
Comparison of the surface tension of the polymer (Floc 572) and surface-active agent (CTAB)
ProductpHγs(mn/m)γi(mn/m) oil Aγi (mn/m) heptane
Demineralized water672a 21.548,3
Floc 572 0,1%of 6.49542123,78
CTAB 0,1%6,8330,292,73

1. The use of Quaternary polyamines of the formula (I) for oil recovery from carbonate reservoirs

where n≥1;
R1represents N, CH3CH2CH3CnH2n+1;
R2represents H2SNONCE2CH2CH2CH=CH2;
R3represents CH3CH2CH3CnH2n+1;
R4represents CH3CH2CH=CH2;
if R2and R4are allyl groups, they together may form an aliphatic cyclic structure; the ratio between the atoms of carbon and nitrogen (C/N) is in the range from 2 to 30.

2. The use of Quaternary polyamines according to claim 1, where n≥2.

3. The use of Quaternary polyamines according to claim 1, where the ratio m is waiting for atoms of carbon and nitrogen (C/N) is in the range from 2 to 20.

4. The use of Quaternary polyamines according to claim 3, where the ratio between the atoms of carbon and nitrogen (C/N) is in the range from 2 to 12.

5. The use according to claim 1 where the Quaternary polyamine selected from the following structures:


6. The use according to claim 1 where the Quaternary polyamine is a chloride of polydiallyldimethyl.

7. The use according to claim 1, where polyamine copolymerizable with polymers selected from the group consisting of polyacrylamides, polyamides, PEO, additives, obtained by quaternization of the reaction product of manniche obtained by the interaction of formaldehyde, polyacrylamide and a secondary amine.

8. The use according to claim 7, where the molar percentage of the polymer is lower than 30%.

9. The use of claim 8, where the molar percentage of the polymer is lower than 20%.

10. The use according to claim 1, where polyamine support interfacial tension of crude oil level >2 mn/m

11. The use of claim 10, where polyamine support interfacial tension of crude oil at a rate of >5 mn/m

12. The application of claim 11, where polyamine support interfacial tension of crude oil at a rate of >10 mn/m

13. The method of increasing oil recovery from carbonate reservoirs, which involves the dissolution of the polyamines according to claim 1 in water or in saline solution at concentrations in the range of from 0.1% to 20% and the subsequent introduction into the well.

14. The method according to item 13, where polyamine present in concentrations in the range of from 0.01% to 10%.

15. The method according to 14, where polyamine present in concentrations in the range from 0.05% to 5%.



 

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14 cl, 5 ex, 4 dwg

FIELD: oil and gas production.

SUBSTANCE: method of treating underground formation through which goes the bore can be put into practice by forming treatment fluid from hydrated polymer water solution that is mixed with water-soluble, non-symmetric, heretolytically cleaved, nonorganic peroxide diluting agent and the fluid if injected into formation.

EFFECT: increasing the treatment efficiency.

14 cl, 5 ex, 4 dwg

FIELD: oil and gas production.

SUBSTANCE: plugging material contains cement, reinforcing fibre-polyacrylic or polypropylene or basalt fibre, polydiallyldimetylammonium chloride-VPK-402, hydroxyethyl cellulose, super plastifier CEMPLAST or C-3 or Melflux, anti-foaming agent POLYCEM DF, calcium chloride and water with the following component ratio, wt %: cement 65.0-69.0, said reinforcing fibre 0.08-0.33, hydroxyethyl cellulose 0.07-0.2, said super plastifier 0.08-0.33, said anti-foaming agent 0.08-0.13, calcium chloride 0.08-1.3, polydiallyldimetylammonium chloride-VPK-402 0.08-0.33, water the rest.

EFFECT: improvement of crash resistance, including conditions of hard dynamic influences.

1 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: compound is a set of expoxide-containing resin containing a resinous part and amine-type curing agent. The epoxide resinous base is obtained through epoxidation of an aromatically conjugated hydroxyphenylene, having degree of polycondensation n=2, obtained at temperature 240-260°C from diphenol (alkyl resorcinol), with diglycidyl ether of diethylene glycol with degree of polycondensation n=0-2 in molar ratio 1:5, respectively; epoxidation is carried out at temperature 120-165°C in the presence of 0.15-0.35 wt % 2,4,6-trisdimethylaminomethylphenol to weight ratio of epoxide groups of 6.0-9.0% and the resinous part further contains 15-25 wt % process water and the following content of ingredients of the compound, pts.wt: said resinous part 100, amine-type curing agent 2.0-12.0.

EFFECT: high efficiency of sealing water influx.

2 cl, 1 tbl

Drilling mud // 2458960

FIELD: oil and gas production.

SUBSTANCE: low-clay drilling fluid includes the following, wt %: clay 2.0-3.0, lubricating additive - residual product of wood advanced processing consisting of diterpenes 0.8-1.1, anti-foaming agent 0.2-0.3, water the rest.

EFFECT: improvement of lubricating and filtering parameters of drilling mud.

1 ex, 1 tbl

FIELD: oil and gas production.

SUBSTANCE: clayless drilling mud that includes fluorine-containing acrylamide copolymer and acrylic acid and water contains copolymer of general expression: molecular weight 1.2·106 with fluorine content up to 2%, with the following components ratio, wt %: said copolymer 0.1-0.15, water the rest.

EFFECT: stability of operating parameters up to 120 days at low temperatures.

1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: in the method of treating water-based process liquids used in drilling and well workover, by adding a sodium halide-based clay inhibitor, the clay inhibitor is a furacilin preparation containing furacilin and sodium chloride in amount of 0.8-4.2 wt %.

EFFECT: high efficiency of the treatment method owing to improved inhibiting properties, wide range of clay inhibitors.

11 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: in the method of treating water-based process liquids used in drilling and well workover, by adding a sodium halide-based clay inhibitor, the clay inhibitor is a furacilin preparation containing furacilin and sodium chloride in amount of 0.8-4.2 wt %.

EFFECT: high efficiency of the treatment method owing to improved inhibiting properties, wide range of clay inhibitors.

11 ex, 2 tbl

FIELD: oil and gas industry.

SUBSTANCE: in manufacturing method of ceramic proppant including grinding of initial charge components, preparation of ceramic slurry, introduction to the obtained ceramic slurry of water-soluble polymer binding agent, formation of granules, their drying and calcination, components of initial charge are crushed to the fraction size of not more than 30 mcm at fraction content of not more than 5 mcm - 60-70 wt %, and fraction of 5-30 mcm - 30-40 wt %, formation of granules is performed by dispersion of ceramic slurry at least through one gauged opening to water solution of fixing substance forming together with water-soluble polymer binding agent the water-nonsoluble compound providing the fixation of granule shape, to ceramic slurry there introduced in addition is phosphoric sodium salt in the quantity of 0.03 - 0.5 wt % of the weight of solid ceramic slurry component. Ceramic proppant is characterised by the fact that it has been obtained with the above method. Invention is developed in dependent claims.

EFFECT: improving proppant package permeability.

4 cl, 2 ex, 1 tbl, 3 dwg

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