Procedure for removal of filtration sediment in oil wells

FIELD: metallurgy.

SUBSTANCE: according to procedure polymer material settled on porous medium is removed into solution. The procedure consists in contacting the said polymer material with a water composition including (a) catalyst chosen from: (a1) complex with general formula (I) Fe++(L)nYs, where L corresponds to ligand chosen from combinations of general formula (II), where X=CH, N, (a2) of dissolved in water cobalt salt (2+), preferably, cobalt acetate, (b) oxidant chosen from: (b1) hydrogen peroxide, (b2) MHSO5 where M corresponds to alkali metal, preferably, potassium with the following restriction: catalyst (a1) can be used only at presence of oxidant (b1), while catalyst (a2) can be used only at presence of oxidant (b2).

EFFECT: removal of polymer material into solution at moderately low temperatures and at pressure in depleted horizontal wells.

13 cl, 8 tbl, 62 ex

 

This invention relates to a method of removing filtration of precipitation, resulting in oil wells during drilling operations, by processing these filtration precipitation with aqueous solutions of specific oxidative systems, is also effective at low temperatures.

In the last few years an increasing interest has been focused on the development of new fluids for drilling and maintenance, is capable of limited destroy industrial education caused by their use. This is mainly because of the formation at the borehole wall filtration precipitation able during the drilling of wells to reduce I used liquids and solids and/or products in the porous matrix. However, once the well is put into operation, for high values of performance of this filter cake should be completely uniform way to delete.

Removal technologies available at the present time, based on the use of different types of chemical additives, such as acids, chelat forming agents, enzymes, oxidizing agents.

In U.S. patent US-A-5507905 described an improved method of removing filtration of precipitation through the use of inorganic peroxides as oxidizing agents. More specifically, in the method according to US-A-607905 described the introduction of a filter cake peroxides, alkaline earth metal or zinc, followed by processing the above-mentioned filtration precipitation with acid solutions.

In US-A-5247995 described method of removing filtration of precipitation containing polysaccharides, by treating aqueous solutions containing enzymes that can decompose polysaccharides, or by treatment with an oxidising agent selected from non-metallic persulfate.

These methods, which describe the destruction of filtration precipitation introduction to solid precursors oxidizing agents, are not sufficiently reliable, since the above solids are not completely insoluble at operating temperatures. Thus, part of these oxidants prematurely released with subsequent premature degradation of polymers. In addition, these compounds have two disadvantages, namely, they can only be used at high pH and in the absence of significant quantities of reducing agents.

Finally, in WO 00/08112 described method of removing filtration of precipitation based on polysaccharides by processing these filtration precipitation salt solutions, are able to form a bromide or bromate.

All of these solutions to this technical problem removal filtration precipitation have the disadvantage that they, inter alia, perform satisfactorily only in vertical wells, characterized by high pressures and moderately high temperatures.

The authors have developed a method that satisfies the above requirements.

In accordance with this invention, a method of translation in a solution of polymeric material deposited on a porous medium, which includes the conversion of the specified polymer material in contact with the aqueous composition, and specified water composition includes:

(a) a catalyst selected from:

(A1) complex having General formula (I)

where n is an integer from 1 to 3;

Y independently represents a group of anionic nature, associated with Fe++in ion pair as the anion, or covalent bond "σ"-types:

"s" represents the number of groups Y, which is sufficient to neutralize the formal oxidation state of Fe++and equal to 2 if all the groups Y are monovalent;

L represents a ligand selected from groups having the General formula (II)

where X=CH, N;

R1and R2, Odin is new or different, selected from-H, -COOH and C1-With5-alkyl radicals, preferably from H and COOH;

(A2) water-soluble salts of cobalt (2+), preferably of cobalt acetate;

(b) an oxidizer selected from:

(b1) hydrogen peroxide,

(b2) MHSO5where M represents an alkali metal, preferably potassium;

with the limitation that the catalyst (A1) can be used only in the presence of an oxidising agent (b1)and the catalyst (A2) can be used only in the presence of an oxidising agent (b2).

As for the polymer material, typical examples are polysaccharides, polyacrylamides, polyacrylic acid and the corresponding copolymers; xanthan gum, amides with different degrees of cross-linkage, cellulose.

Typical examples of ligands based on carboxylic acids having the General formula (II)are pyridine-2-carboxylic acid, pyrazin-2-carboxylic acid, 2,6-pyridinedicarboxylate acid, 2,3-pyrazinecarboxamide acid. A preferred compound having the General formula (II)is pyridine-2-carboxylic acid.

The complex having General formula (I)can be formed either before or, preferably, to form "in situ" by adding components, i.e. ligand L and salts of iron (II). In the latter case, you can use the molar ratio between the ligand and Fe++in the range of the t 1/1 to 30/1, preferably from 1/1 to 10/1.

The oxidant can be submitted together with the aqueous solution (I), or after or before its filing.

If the oxidant is hydrogen peroxide, it is possible to use an aqueous solution with a concentration of from 5 to 40 wt.%, preferably from 10 to 30 wt.%.

The aqueous composition according to the present invention has a content of Fe++in the range from 0.5 to 10 mmol/l, preferably from 1 to 5 mmol/L.

In addition, when using hydrogen peroxide is present in the final water composition at a concentration in the range from 0.5 to 10 wt.%, preferably from 1 to 5 wt.%.

If the oxidant is MHSO5in this case, it also used an aqueous solution, preferably from 5 to 20 wt.%.

A significant advantage of the method according to this invention is the fact that it is also effective when relatively low temperatures, i.e. from 25 to 60°C.

The authors also note that the method according to this invention allows to restore the original values of permeability, as will be shown in the experimental part.

The efficiency of the method according to this invention was first investigated in conditions of periodic tasks in order to assess the time required to reduce the viscosity of polymer solutions or, in the case of amides, for complete dissolution of the polysaccharide.

E is Sperimentale part of the described tests, conducted in accordance with the method according to this invention, and comparative tests carried out in the presence of other oxidizing systems.

In particular, we have evaluated the following oxidants: H2O2, KHSO5, (NH4)2S2O8, NaClO, tBuOOH and Na2BO3.

We used the following catalysts: FeSO4, Co(OAc)2, Cu(SLA)2or their complexes with nitrogen-containing ligands (add, phenanthroline, pyridine-2-carboxylic acid, pyrazin-2-carboxylic acid, 2,6-pyridinedicarboxylate acid, 2,3-pyrazinecarboxamide acid), selected for their ability to modify the redox potential of the metal and because of their high stability in oxidizing conditions.

It was shown that of all different the considered systems (see experimental part) are effective only system according to this invention.

Then evaluated the effect of different salt solutions (KCl 3%, CaCl225%, CaBr245%, SOOK 20%) on the behavior of the selected systems. This study showed that oxidative system based on the hydrogen peroxide is also effective in the presence of salt solutions.

To change system activity on the basis of hydrogen peroxide studies have been conducted while changing the concentration of catalyst and temperature. It turned out Thu the time of decomposition of the polymers can be modified in such a way in accordance with the requirements. This, of course, is another significant advantage of this method.

Characteristics of products formed during the oxidation, obtained by ultrafiltration and gel permeation chromatography, revealed the complete disappearance of the polymers and the formation of fragments with low molecular weight corresponding to 1-5 units of glucose.

The following examples are given for better understanding of this invention.

Examples

Table 1 shows the data related to the decomposition of the xanthan gums in the presence of different oxidation systems, possibly in the presence of catalysts (tests 1-24). The data in the table show the higher efficiency of the systems according to this invention.

In tables 2 (test 25-29), 3 (testing 30-36), 4 (test 37-41) and 5 (test 42-46) respectively shows the tests on the decomposition of scleroglucan, skingley and two different starches in the presence of systems according to this invention. In these tables also provide various comparative tests.

Table 6 shows the effect of the concentration of the catalyst on the decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid.

Table 7 summarizes the effect of temperature on the rate of decomposition in the presence of system soglasovannom invention.

Table 8 describes the tests that show the effect of salt solution on time decomposition in the presence of system H2O2/FeSO4/PyCOOH.

Finally, testing 60-62 refer to testing to remove sediment filtration.

Comparative example 1. Decomposition of xanthan resin with hydrogen peroxide

The test on the decomposition was performed using a solution of N-VISR(supplied by Baroid), obtained by dissolving 1.2 g of polysaccharide in 200 ml of deionized water using a stirrer of Silversea.

The initial value of the viscosity, measured using a rotational viscometer FANN 35 SA configuration of the rotor R1B1 at speeds of 5.1 with-1was 200.

To the resulting solution was added 1.2 g of hydrogen peroxide at a concentration of 30 wt.% (10.6 mmol) and then the mixture was kept under static conditions at a temperature of 35°C.

The rate of decomposition was evaluated by measuring the time required to achieve a viscosity of lower than 10 MPa·S.

After 24 hours in the above-described conditions, the viscosity remained unchanged.

Comparative example 2. Decomposition of xanthan resin with hydrogen peroxide catalyzed by FeSO4

The test was performed in the conditions described for example 1 using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.%(10.6 the mol). and as catalyst (0.16 g (of 0.58 mmol) FeSO4*7H2O (the molar ratio of oxidant/catalyst = 18).

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 4 hours.

Comparative example 3. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Fe/etc

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.%(10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.51 g (1,74 mmol) add (ethylenediaminetetraacetic acid).

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 1 hour.

Comparative example 4. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Fe/ 1,10-phenanthrolin

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.34 g (1,74 mmol) 1,10-phenanthroline.

It was shown that when operating in static conditions at 35°C the time required for snizeni the viscosity of 10 MPa·s, is 4 hours.

Comparative example 5. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 3 minutes.

Comparative example 6. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Fe/perintalmanna acid

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.22 g (1,74 mmol) pyrazinecarboxamide acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 10 minutes.

Comparative example 7. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Fe/2,6-pyridinedicarboxylate acid

Test the s was performed in the conditions, described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.29 grams (1,74 mmol) of 2,6-pyridinedicarboxylic acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 10 minutes.

Comparative example 8. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Fe/2,3-pyrazinecarboxamide acid

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.29 grams (1,74 mmol) of 2,3-pyrazinecarboxamide acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 3 minutes.

Comparative example 9. Decomposition of xanthan resin monopersulfate potassium

The tests were carried out under the conditions described in example 1, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol) in the absence of a catalyst.

When operating in static conditions at 35°C after 2 hours, the viscosity remained unchanged.

Comparative example 10. Decomposition of xanthan resin monopersulfate potassium catalyzed FeSO4.

The test was performed under the conditions described in example 1, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.16 g (of 0.58 mmol) FeSO4*7H2O.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 16 hours.

Comparative example 11. Decomposition of xanthan resin monopersulfate potassium catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 1, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C time. necessary to reduce the viscosity of 10 MPa·s, is 8 minutes.

Comparative example 12. Decomposition of xanthan resin monopersulfate potassium catalyzed by the complex Fe/perintalmanna acid

The test was performed under the conditions described in example 1, using as oxidant 3.2 g mo is persulfate potassium (KHSO 5- concentration mos.% (9.9 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyrazinecarboxamide acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 4 hours.

Comparative example 13. Decomposition of xanthan resin peroxydisulfate ammonium

The test was performed under the conditions described in example 1, using as oxidant 2.3 g of peroxydisulfate ammonium [(NH4)2S2O8] in the absence of a catalyst.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 12 hours.

Comparative example 14. Decomposition of xanthan resin peroxydisulfate ammonium catalyzed FeSO4

The test was performed under the conditions described in example 1, using as oxidant 2.3 g of peroxydisulfate ammonium [(NH4)2S2O8] (10.1 mmol), and catalyst (0.16 g (of 0.58 mmol) FeSO4*7H2O.

It was shown that when operating in static conditions at 35°C time. necessary to reduce the viscosity of 10 MPa·s, is 2 hours.

Comparative example 15. Decomposition of xanthan resin peroxydisulfate ammonium, Catala is projected by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 1, using as oxidant 2.3 g of peroxydisulfate ammonium [(NH4)2S2O8] (10.1 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity to 10 MPa, is 4 hours.

Comparative example 16. Decomposition of xanthan resin peroxydisulfate ammonium catalyzed by the complex Fe/perintalmanna acid

The test was performed under the conditions described in example 1, using as oxidant 2.3 g of peroxydisulfate ammonium [(NH4)2S2O8] (10.1 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.22 g (1,74 mmol) pyrazinecarboxamide acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity to 10 MPa, is 2 hours.

Comparative example 17. Decomposition of xanthan resin with hydrogen peroxide catalyzed by Co(CH3Soo)2

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt. (10.6 mmol), and as catalyst (0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 10 hours.

Comparative example 18. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex With/pyridine-2-carboxylic acid

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C viscosity remained unchanged after 24 hours.

Comparative example 19. Decomposition of xanthan resin monopersulfate ammonium catalyzed by Co(CH3Soo)2

The test was performed under the conditions described in example 1, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O. it Was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 3 minutes.

Sravnitelnyye 20. Decomposition of xanthan resin monopersulfate potassium catalyzed by complex/pyridine-2-carboxylic acid

The test was performed under the conditions described in example 1, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 7 hours.

Comparative example 21. Decomposition of xanthan resin by hydrogen peroxide, catalyzed si(CH3Soo)2

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst (0.12 g (0,60 mmol) si(CH3Soo)2*H2O.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 30 minutes.

Comparative example 22. Decomposition of xanthan resin with hydrogen peroxide catalyzed by the complex Cu/pyridine-2-carboxylic acid

The test was performed under the conditions described in example 1, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (0.6 mmol), and as the catalyst complex obtained by the addition of 0.12 g (0,60 mmol) Cu(CH3Soo)2*H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

When operating in static conditions at 35°C after 24 hours the viscosity remained unchanged.

Comparative example 23. Decomposition of xanthan resin monopersulfate ammonium catalyzed by Cu(CH3Soo)2

The test was performed under the conditions described in example 1, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.12 g (0,60 mmol) Cu(CH3Soo)2*H2O.

When operating in static conditions at 35°C after 24 hours the viscosity remained unchanged.

Comparative example 24. Decomposition of xanthan resin monopersulfate potassium catalyzed by complex Cu/pyridine-2-carboxylic acid

The test was performed in the conditions described for example 1, using as oxidant 3.2 g of monopersulfate potassium (SO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.12 g (0,60 mmol) Cu(CH3Soo)2*H2O and 0.22 g (1,74 mmol) pyridine-2-carboxylic acid.

When operating in static conditions at 35°C after 24 hours the viscosity remained unchanged.

Comparative example 25. The decomposition is scleroglucan hydrogen peroxide

Test the decomposition was performed using a solution BIOVIS (supplied by SKW Trostberg), obtained by dissolving 1.2 g of polysaccharide in 200 ml of deionized water through the mixer of Silversea.

It was shown that the initial value of the viscosity, measured using a rotational viscometer FANN 35 SA configuration of the rotor R1B1 at 5.5 with-1was equal to 200.

To the resulting solution were added 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol) and then this mixture is maintained under static conditions at a temperature of 35°C.

The rate of decomposition was evaluated by measuring the time. required to achieve a viscosity of lower than 10 MPa·S.

When in the above-described conditions after 24 hours the viscosity remained unchanged.

Example 26. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 25, using as oxidant 1.2 hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid (the molar ratio of agent-oxidant/catalyst = 18).

It was shown that when operating in static conditions at 35°C time. neo is required to reduce the viscosity of 10 MPa·s, is 20 minutes.

Comparative example 27. Decomposition of scleroglucan monopersulfate potassium

The test was performed under the conditions described in example 25, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol) without a catalytic Converter.

When operating in static conditions at 35°C after 24 hours the viscosity remained unchanged.

Comparative example 28. Decomposition of scleroglucan monopersulfate potassium catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 25, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C time. necessary to reduce the viscosity of 10 MPa·s, is 1 hour.

Comparative example 29. Decomposition of scleroglucan monopersulfate potassium catalyzed by Co(CH3Soo)2

The test was performed under the conditions described in example 25, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.15 g (0,60 mmol of Co(CH 3Soo)2*4H2O.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 15 minutes.

Comparative example 30. Decomposition actinglike hydrogen peroxide

Test the decomposition was performed using a solution FLOPACR(supplied by Halliburton), obtained by dissolving 6.0 g of polysaccharide in 200 ml of deionized water using a stirrer of Silversea.

It was shown that the initial value of the viscosity, measured using a rotational viscometer FANN 35 SA configuration of the rotor R1B1 at 5.5 with-1equal to 450.

To the resulting solution were added 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol) and the mixture maintained under static conditions at a temperature of 35°C.

The rate of decomposition was evaluated by measuring the time required to achieve a viscosity of lower than 10 MPa·S. When working in the above-described conditions after 24 hours the viscosity remained unchanged.

Example 31. Decomposition actinglike hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 30, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding the 0.16 g (of 0.58 mmol) FeSO 4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity to 10 MPa, is 10 minutes.

Comparative example 32. Decomposition actinglike monopersulfate potassium

The test was performed under the conditions described in example 30, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol) without a catalytic Converter.

When operating in static conditions at 35°C after 24 hours the viscosity remained unchanged.

Comparative example 33. Decomposition actinglike monopersulfate potassium catalyzed by complex Re/pyridine-2-carboxylic acid

The test was performed under the conditions described in example 30, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 2 hours.

Comparative example 34. Decomposition actinglike monopersulfate potassium catalyzed by Co(CH3Soo)2

The test was carried out at conditions is s, described in example 30, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s is 10 minutes.

Comparative example 35. Decomposition actinglike peroxydisulfate ammonium

The test was performed under the conditions described in example 1, using as oxidant 2.3 g of peroxydisulfate ammonium [(NH4)2S2O8] (10.1 mmol) in the absence of a catalyst.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s is 14 hours.

Comparative example 36. Decomposition actinglike peroxydisulfate ammonium catalyzed FeSO4

The test was performed under the conditions described in example 1, using as oxidant 2.3 g of peroxydisulfate ammonium [(NH4)2S2O8] (10.1 mmol), and catalyst (0.16 g (of 0.58 mmol) FeSO4*7H2O.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 1 hour.

Comparative example 37. The decomposition of starch peroxide is odorata

Test the decomposition was performed using a suspension FLOTROLR(MI)obtained by adding 2 g of the polysaccharide to 200 ml of deionized water.

To the mixture was added 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol) and the mixture is then maintained at low stirring at 35°C.

The rate of decomposition was evaluated by measuring the time required for complete dissolution of the polysaccharide.

When working in the above-described conditions, the suspension remained unchanged after 24 hours.

Example 38. The decomposition of starch by hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 37, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in the above-described conditions at 35°C the time required for complete dissolution of the polysaccharide, is 50 minutes.

Comparative example 39. The decomposition of starch by monopersulfate potassium

The test was performed under the conditions described in example 37, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with conc what Tracia 47 wt.% (9.9 mmol) without a catalytic Converter.

When working in the above-described conditions, the suspension remained unchanged after 24 hours.

Comparative example 40. The decomposition of starch by monopersulfate potassium catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 37, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid. It was shown that when operating in the above-described conditions at 35°C the time required for complete dissolution of the polysaccharide, was 3 hours.

Comparative example 41. The decomposition of starch by monopersulfate potassium catalyzed by Co(CH3Soo)2

The test was performed under the conditions described in example 37, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O.

It was shown that when operating in the above-described conditions at 35°C the time required for complete dissolution of the polysaccharide, was 25 minutes.

Comparative example 42. The decomposition of starch by hydrogen peroxide

Test the decomposition was performed with use the of suspension DUALFLO R(MI)obtained by adding 2 g of the polysaccharide to 200 ml of deionized water.

To the mixture was added 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol) and then supported it with weak stirring at 35°C.

The rate of decomposition was evaluated by measuring the time required for complete dissolution of the polysaccharide.

When working in the above-described conditions, the suspension after 24 hours has remained virtually unchanged.

Example 43. The decomposition of starch by hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 42, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by adding 0.16 g (0.58, up mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in the above-described conditions at 35°C the time required for complete dissolution of the polysaccharide was 40 minutes.

Comparative example 44. The decomposition of starch by monopersulfate potassium

The test was performed under the conditions described in example 42, using agent-oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol) without a catalytic Converter.

When operating the above-described conditions, the suspension remained unchanged after 24 hours.

Comparative example 45. The decomposition of starch by monopersulfate potassium catalyzed by the complex Fe/pyridin-2-carboxylic acid

The test was performed under the conditions described in example 42, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst complex obtained by adding 0.16 g mg (of 0.58 mmol) FeSO4*7H2O and 0.21 g (1,74 mmol) pyridine-2-carboxylic acid.

It was shown that when operating in the above-described conditions at 35°C the time required for complete dissolution of the polysaccharide is 1 hour.

Comparative example 46. The decomposition of starch by monopersulfate potassium catalyzed by Co(CH3Soo)2

The test was performed under the conditions described in example 42, using as oxidant 3.2 g of monopersulfate potassium (KHSO5) with a concentration of 47% by weight (9.9 mmol), and catalyst (0.15 g (of 0.60 mmol) With(CH3Soo)2*4H2O.

It was shown that when operating in the above-described conditions at 35°C the time required for complete dissolution of the polysaccharide, is 20 minutes.

Example 47. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid: the effect of concentration of catalyst

The test was performed under the conditions described in the example is 26, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.%(10.6 mmol), and catalyst complex obtained by adding 64 mg (0.23 mmol) FeSO4*7H2O and 84 mg (0.69 mmol) of pyridine-2-carboxylic acid (the molar ratio of oxidant/catalyst = 46).

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s is 30 minutes.

Example 48. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the effect of the concentration of catalyst

The test was performed under the conditions described in example 26, using as oxidant 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and catalyst complex obtained by the addition of 32 mg (0.12 mmol) FeSO4*7H2O and 44 mg (0.36 mmol) of pyridine-2-carboxylic acid (the molar ratio of oxidant/catalyst = 88).

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, is 4 hours.

Example 49. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the effect of the concentration of catalyst

The test was performed under the conditions described in example 26, using as about what elites 1.2 g of hydrogen peroxide with a concentration of 30 wt.% (10.6 mmol), and as the catalyst complex obtained by adding 16 mg (0.06 mmol) FeSO4*7H2O and 22 mg (0.18 mmol) pyridine-2-carboxylic acid (the molar ratio of oxidant/catalyst = 177).

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s is 18 hours.

Example 50. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the influence of temperature

The test was performed under the conditions described in example 26.

It was shown that when operating in static conditions at 25°C. the time required to reduce the viscosity of 10 MPa·s, is 90 minutes.

Example 51. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the influence of temperature

The test was performed under the conditions described in example 26.

It was shown that when operating in static conditions at 50°C. the time required to reduce the viscosity of 10 MPa·s, is 10 minutes.

Example 52. Decomposition of scleroglucan monopersulfate potassium catalyzed by Co(CH3Soo)2the influence of temperature

The test was performed under the conditions described in example 29.

It was shown that when operating in static conditions at 25°C. the time required to reduce the viscosity of 10 MPa·s,is 60 minutes.

Example 53. Decomposition of scleroglucan monopersulfate potassium catalyzed by Co(CH3COO)2the influence of temperature

The test was performed under the conditions described in example 29.

It was shown that when operating in static conditions at 50°C. the time required to reduce the viscosity of 10 MPa·s, is 8 minutes.

Example 54. The decomposition of starch by hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the influence of temperature

The test was performed under the conditions described in example 38.

It was shown that when operating in static conditions at 25°C. the time required to reduce the viscosity of 10 MPa·s, is 75 minutes.

Example 55. The decomposition of starch by hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the influence of temperature

The test was performed under the conditions described in example 38.

It was shown that when operating in static conditions at 50°C. the time required to reduce the viscosity of 10 MPa·s, is 6 minutes.

Example 56. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the effect of salt solution (KCL)

The test was performed under the conditions described in example 26, by dissolving the polysaccharide in 200 ml of an aqueous KCl solution with a concentration of 3 wt.%.

It was shown that when working in catechesi conditions at 35°C time, necessary to reduce the viscosity of 10 MPa·s, 25 minutes.

Example 57. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the effect of salt solution (CaCl2)

The test was performed under the conditions described in example 26, by dissolving the polysaccharide in 200 ml aqueous solution of CaCl2with a concentration of 25 wt.%.

It was shown that when operating in static conditions at 35°C the time required to reduce the viscosity of 10 MPa·s, 25 minutes.

Example 58. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the effect of salt solution (CaBr2)

The test was performed under the conditions described in example 26, by dissolving the polysaccharide in 200 ml of an aqueous solution CaBr2with a concentration of 45 wt.%.

When working in such conditions, the suspension remained unchanged after 24 hours.

It was confirmed decomposition CaBr2with the formation of Br2.

Example 59. Decomposition of scleroglucan hydrogen peroxide catalyzed by the complex Fe/pyridin-2-carboxylic acid, the effect of salt solution (NOOK)

The test was performed under the conditions described in example 26, by dissolving the polysaccharide in 200 ml of an aqueous solution of potassium formate with a concentration of 20 wt.%.

When working in vishey the above conditions, the suspension remained unchanged after 24 hours.

Was confirmed by the decomposition of potassium formate with the formation of CO2.

Example 60. Remove sediment filtration

The initial permeability of the ceramic filter (diameter: 63.5 mm (2.5 inches), thickness: 6.4 mm (0.25 inch), porosity: 5 µm) was determined using a dynamic filter press designed for operation in conditions of high temperature and high pressure (NTR), measuring the time required for passing 200 ml of an aqueous KCl solution with a concentration of 3% at a pressure of 0.7 MPa (7 bar) at 40°C.

Then the cell was filled with liquid having the following composition:

Water350 ml
KCl10,5 g
BIOVISR(scleroglucan)1,75 g
DUALFLOR(starch)7.0 g
Caso335 g

Education filtration the precipitate was obtained by maintaining the cell under a pressure of 2.1 MPa (21 bar) under stirring (600 rpm) for 30 minutes. After washing with water was conducted removing filtration of sediment by adding in a cell, present and degrades solution having the following composition:

Water350 ml
KCl10,5 g
Hydrogen peroxide (net)the 5.25 g
FeSO4100 mg
Pyridine-2-carboxylic acid110 mg

The solution was kept under static conditions for 4 hours at 40°C.

After washing with water was determined residual permeability by measuring the time required for passing 200 ml of an aqueous KCl solution with a concentration of 3% under a pressure of 0.7 MPa (7 bar) at 40°C.

The results were as follows:

The initial permeability: 20/200 ml

The final permeability: 20/200 ml

Restoring permeability: 100%

Example 61. Remove sediment filtration

The test was performed under the conditions described in example 60, but using for the formation of a sediment filtration following liquid:

Water350 ml
KCl10,5 g
N-VISR(xanthan gum)1,75 g
DUALFLOR(rahmel) 7.0 g
Caso335 g

After processing the corrosive solution were obtained the following results:

The initial permeability:20/200 ml
The final permeability:20/200 ml
Restoring permeability:100%

Example 62. Remove sediment filtration

The test was performed under the conditions described in example 60, but for the formation of the filtration sludge used the following liquid:

Water350 ml
KCl10,5 g
BlOVISR(scleroglucan)1,75 g
FLOTROLR(starch)7.0 g
Caso335 g

After processing the corrosive solution were obtained the following results:

The initial permeability: 20 /200 ml
The final permeability:20 /200 ml
Restoring permeability:100%

H2O2
Table 1
Decomposition of xanthan gums (N-VIS)
ExampleThe oxidizing agentCatalystThe ligandTime decay
1CH2O2-->24 hours
2CH2O2FeSO4-4 hours
3CH2O2FeSO4Phen4 hours
4H2O2FeSO4Add1 hour
5FeSO4PyCOOH3 min
6H2O2FeSO4PyrCOOH10 min
7H2O2FeSO4Py(COOH)210 min
8H2O2FeSO4Pyr(COOH)23 min
9s(NH4)2S2O8--12 hours
10C(NH4)2S2O8FeSO4-2 hours
11S(NH4)2S2O8FeSO4PyCOOH4 hours
12s(NH4)2S2O8 FeSO4PyrCOOH2 hours
13CKHSO5-->24 hours
14CKHSO5FeSO4-16 hours
15CKHSO5FeSO4PyCOOH8 min
16CKHSO5FeSO4PyrCOOH4 hours
17cH2O2Co(OAc)2-10 hours
18CH2O2Co(OAc)2PyCOOH>24 hours
19 (C)KHSO5Co(OAc)23 min
20s KHSO5Co(OAc)2PyCOOH9 hours
SH2O2Co(OAc)230 min
22pH2O2Co(OAc)2PyCOOH>24 hours
23 ° CKHSO5Co(OAc)2>24 hours
24CKHSO5Co(OAc)2PyCOOH>24 hours

Abbreviations:

Add(ethylenediaminetetraacetic acid)

Phen(1,10-phenanthrolin)

Ru(COOH)(pyridine-2-carboxylic acid)

PyrCOOH(pyrazin-carboxylic acid)

Ru(COOH)2(pyridine-2,6-dicarboxylic acid)

Pyr(COOH)2(pyrazin-2,3-dicarboxylic acid)

Table 2
Decomposition of scleroglucan (BlOVIS)
Example The oxidizing agentCatalystThe ligandTime decay
25sH2O2-->24 hours
26H2O2FeSO4Racoon20 min
27KHSO5-->24 hours
28CKHSO5FeSO4Racoon1 hour
29KHSO5With(SLA)2-15 min

Table 3
Decomposition skingley (FLOPAC)
ExampleThe oxidizing agentCatalystThe ligand Time decay
30CH2O2-->24 hours
31H2O2FeSO4Racoon10 min
32CKHSO5-->24 hours
33KHSO5FeSO4Racoon2 hours
34KHSO5With(SLA)2-10 min
35S(NH4)2S2O8--14 hours
36C(NH4)2S2O8FeSO4-1 hour

Table 4
The decomposition of starch (FLOTROL)
ExampleThe oxidizing agentCatalystThe ligandTime decay
SH2O2-->24 hours
38H2O2FeSO4Racoon50 min
39CKHSO5-->24 hours
40sKHSO5FeSO4Racoon3 hours
41KHSO5With(SLA)2-25 min

Table 5
The decomposition of starch (DUALFLO)
ExampleThe oxidizing agentCatalystThe ligandTime decay
42sH2O2-->24 hours
43H2O2FeSO4Racoon40 min
SKHSO5-->24 hours
45CKHSO5FeSO4Racoon1 hour
46KHSO5With(SLA)2-20 min

Table 6
Decomposition of scleroglucan (BlOVIS) with hydrogen peroxide catalyzed by the complex Fe/ pyridin-2-carboxylic acid, the effect of the concentration of catalyst
ExampleSubstrateThe oxidant/ catalyst/ligandThe molar ratio of oxidant/ catalystTime decay
25BIOVISH2O2/FeSO4/PyCOOH1820 min
47BIOVISH2O2/FeSO4/PyCOOH4630 min
48BIOVISH2O2/FeSO4/PyCOOH884 hours
49BIOVISH2O2/FeSO4/PyCOOH17718 hours

Table 7
The influence of temperature
ExampleSubstrateThe oxidant/ catalyst/ligandTemperature (°C)Time time is ogene
26BIOVISH2O2FeSO4/PyCOOH3520 min
50BIOVISH2O2/FeSO4/PyCOOH2590 min
51BIOVISH2O2/FeSO4/PyCOOH5010 min
29BIOVISKHSO5/Co(OAc)2/-3515 min
52BIOVISKHSO5/Co(OAc)2/-2560 min
53BIOVISKHSO5/Co(OAc)2/-508 min
38FLOTROLH2O2/FeSO4/PyCOOH3550 min
54FLOTROLH 2O2/FeSO4/PyCOOH2575 min
55FLOTROLH2O2/FeSO4/PyCOOH506 min

Table 8
The effect of salt solution (summary table)
ExampleSubstrateThe oxidant/catalyst/ligandThe salt solutionTime decay
26BIOVISH2O2/FeSO4/PyCOOH-20 min
56BIOVISH2O2/FeSO4/PyCOOHKCl 3%25 min
57BIOVISH2O2/FeSO4/PyCOOHCaCl225%25 min
28BIOVISH2 O2/FeSO4/PyCOOHCaBr245%>24 hours
59BIOVISH2O2/FeSO4/PyCOOHNCOOK 20%>24 hours

1. The transfer method in the solution of polymeric material deposited on a porous medium, which includes the conversion of the specified polymer material in contact with the aqueous composition, with the specified water composition includes
(a) a catalyst selected from
(a1) complex having General formula (I)
where n is an integer from 1 to 3,
Y independently represents a group of anionic nature, associated with Fe++in ion pair as the anion or the covalent bond "σ"is type; "s" represents the number of groups Y, which is sufficient to neutralize the formal oxidation charge of Fe++and equal to 2 if all the groups Y are monovalent;
a L is a ligand selected from the compounds having General formula (II)

where X=CH, N;
R1and R2same or different selected from the radicals-H, -COOH and C1-C5-alkyl, preferably H and COOH;
(A2) water-soluble salts of cobalt (2+);
(b) an oxidizer selected from
(b1) peroxide is hydrogen;
(b2) MHSO5where M represents an alkali metal;
with the limitation that the catalyst (a1) can be used only in the presence of an oxidising agent (b1)and the catalyst (A2) can be used only in the presence of an oxidising agent (b2).

2. The method according to claim 1, in which the ligand L is a pyridine-2-carboxylic acid.

3. The method according to claim 1, wherein the water-soluble salt of cobalt (2+) is cobalt acetate.

4. The method according to claim 1, in which (b2) M=K.

5. The method according to claim 1, in which hydrogen peroxide is used in the form of an aqueous solution having a content of N2About2in the range from 5 wt.% up to 40 wt.%.

6. The method according to claim 5, in which hydrogen peroxide is used in the form of an aqueous solution having a content of H2O2in the range of 10 wt.% up to 30 wt.%.

7. The method according to claim 1, wherein the aqueous composition has a concentration of Fe++in the range from 0.5 to 10 mmol/L.

8. The method according to claim 7, in which the aqueous composition has a concentration of Fe++in the range from 1 to 5 mmol/L.

9. The method according to claim 1, wherein the aqueous composition has a concentration of hydrogen peroxide in the range from 0.5 to 10 wt.%.

10. The method according to claim 9, in which the aqueous composition has a concentration of hydrogen peroxide in the range from 1 to 5 wt.%.

11. The method according to claim 1, in which the complex having General formula (I), form the "in situ" by adding components, i.e. ligand L and salts of iron (II).

12. The method according to claim 11, in which the molar ratio between the ligand and Fe++ranges from 1/1 to 30/1.

13. The method according to item 12, in which the molar ratio between the ligand and Fe++ranges from 1/1 to 10/1.



 

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9 ex, 4 tbl, 2 dwg

FIELD: mining.

SUBSTANCE: methods for hydraulic fracturing of subsurface include the first stage, in process of which hydraulic fracturing fluid, which contains thickener, is pumped into well bore to make a crack in subsurface, the second stage, in process of which proppant is added into pumped hydraulic fracturing fluid to prevent crack closure, additionally agents are added into hydraulic fracturing fluid to form proppant clusters or to increase strength of proppant clusters, or to improve transporting capacity of hydraulic fracturing fluid.

EFFECT: formation of crack with high conductivity for reservoir fluid as a result of making strong proppant clusters that prevent crack closure, and channels providing for free flow of reservoir fluids.

67 cl, 4 dwg

FIELD: chemistry.

SUBSTANCE: bored well processing composition which contains an aqueous medium, foam filler, a gaseous component, a surfactant and an agent for providing viscosity, in which the foam filler provides at least approximately an average of 10% increase in value of measured viscosity for at least 10 minutes, measured over an approximately 180 minute estimation interval. In particular, the invention pertains to aqueous compositions for processing bored wells, which are in form of foam containing an agent for providing viscosity, foam filler, a gaseous component and a surfactant, as well as methods of preparing such fluids and use thereof. The agent for providing viscosity can be a hydrating polymer, viscoelastic surfactant or heteropolysaccharide. The foam filler can be a product such as polyoxyalkylene amines, ethylene polyamines, tertiary polyamines, bicarbonate, carbonate, phosphate or sesquicarbonate.

EFFECT: high stability and viscosity.

15 cl, 20 ex, 5 tbl, 5 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing guar gum and use of this gum when processing an underground layer. The method of producing guar gum involves rolling unhulled guar fragments, grinding flake-like unhulled guar fragments to obtain powder of guar gum. The product is obtained using the method given above. The method of processing an underground layer drilled by a well shaft involves formation of processing fluid which contains an aqueous liquid and powder of guar gum containing at least 70 wt % resin material and at least 15 wt % hull material at feeding the processing fluid into the underground layer through the well shaft. The invention is developed in subclaims.

EFFECT: more efficient production of guar gum and use thereof.

24 cl, 6 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing guar gum and use of this gum when processing an underground layer. The method of producing guar gum involves rolling unhulled guar fragments, grinding flake-like unhulled guar fragments to obtain powder of guar gum. The product is obtained using the method given above. The method of processing an underground layer drilled by a well shaft involves formation of processing fluid which contains an aqueous liquid and powder of guar gum containing at least 70 wt % resin material and at least 15 wt % hull material at feeding the processing fluid into the underground layer through the well shaft. The invention is developed in subclaims.

EFFECT: more efficient production of guar gum and use thereof.

24 cl, 6 dwg

FIELD: production and exploratory well drilling, particularly foaming drilling fluids used during penetration through incompetent rock intervals and during primary productive oil and gas deposit opening in the case of abnormally low formation pressure.

SUBSTANCE: 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.

EFFECT: reduced power inputs for well drilling, as well as reduced coefficient of friction between drilling tool and well wall.

1 tbl

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