Method of preparing solid foaming agent for removing liquid from gas or gas condensate wells

FIELD: oil and gas production.

SUBSTANCE: particular objective of invention is removal of high-mineralization (including formation) water and mixtures thereof with gas condensate from marginal gas and gas condensate wells. In a method of preparing solid foaming agent including mixing nonionic surfactant with urea and molding resulting mixture, urea is preliminarily dissolved in water preheated to 50-90°C at weight ratio (9-10):1, respectively, and mixture is then heated to form true solution. Nonionic surfactant is heated to 40-80°C and mixed with true solution of urea at weight ratio (1.0-1.4):1, respectively. Before molding, to resulting liquid-crystalline component mixture is added a water-soluble polymer at weight ratio 1:(0.01-0.05), respectively, or mixture of water-soluble polymer and dissolution retardant at weight ratio liquid-crystalline component mixture/water-soluble polymer/dissolution retardant 1:(0.01-0.05):(0.4-0.6).

EFFECT: increased strength properties of solid foaming agent and enhanced absolute carrying-out capacity thereof.

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The invention relates to oil and gas industry and can be used to remove highly mineralized, including formation, water and their mixtures with condensate from stripper gas and gas condensate wells.

Analysis of the existing state of the art showed the following:

a well - known method of removing liquids from gas wells using solid foaming agent (see U.S. patent No. 4237977 from 02.02.1979, CL EV 21/14, publ. 09.12.1980,, Skyline Produkts Ltd, IMS, issue 81, No. 8, 1981). In the technical solution is presented a method of obtaining a solid foam. Mixed nonionic water-soluble surface-active agent (surfactant) with powdered urea, soak in the form 24-48 h for the formation of a solid adduct of urea and pressed to obtain a higher density of 1200 kg/m3. To remove liquids from gas wells in the last injected obtained adduct of urea, which, if the gas flow through the water forms a foam. This foam gradually from the well liquid is removed.

According to the technology source components - powdered urea and liquid nonionic surfactant are mixed in a ratio of from 1:1 to 9:1 by weight, respectively, which form a coarse heterogeneous system. While nonionic surfactants - adsorbate due to physico-chemical adsorption on the surface of the urea - dt is ranta interacts with the formation of the adduct of urea (complex compounds of urea and nonionic surfactants). On theoretical views of the authors, the result of the desire of the system to reduce the surface energy at the phase boundary occurs adsorption interaction between the source components due to dispersion (van der Waals) forces and induced electrostatic attraction. For the formation of the adduct of urea necessary to overcome the energy barrier (activation energy), which often use the pressure in the urea molecule are rearranged, forming a structure consisting of hexagonal prisms adjacent planes to each other in the form of a honeycomb. With this rearrangement, regardless of the type attachable substance, form one and the same structure with the same arrangement of molecules of urea and the distance between them. Between the planes of the prisms are formed channels that are filled with molecules of nonionic surfactants (straight chain), then there is a formation of the adduct of urea. The shape of the channel resembles a helix, these molecules nonionic surfactants are attached under the action of the dispersion (van der Waals) forces and induced electrostatic attraction. The cross-section of the channel is 6Å wide and 5Å in the narrow part. Nonionic surfactants have areas with direct chain (cross-section 4,1Å)so formed is of the form adducts of urea. Kinetics and completeness of the formation of the adduct of urea are in direct dependence on the specific (interphase) contact surfaces of the system components. As the process of interaction is only on the phase boundary, the molecules of urea inside the particles of the adsorbent will remain unreacted. The result is a solid foaming agent is a solid solution of the adduct of urea and excess urea, and the phase (in varying proportions) is fairly evenly distributed across the volume of the substance in the form of individual dispersed inclusions.

The disadvantage of this method is the following:

- reduced strength properties of solid foam. Urea, being anisotropic crystalline substance in excess, gives a solid foaming agent fragility. The estimated compressive strength - 1.0 MPa, Flexural strength of 0.5 MPa, which can lead to the destruction of the solid foaming agent during transportation or falling into the well.

low absolute carrying capacity of the solid foaming agent.

The results obtained in a laboratory setup, can be expressed in relative or absolute values, which reflect differently indicator carrying capacity of solid foam. Absolute carrying capacity definition is is by the formula

,

where νathe absolute carrying capacity of the solid foaming agent, kg/m3;

Vresidence permitvolume rendered reservoir fluid, m3;

m is the mass of the sample of the solid foaming agent, kg

Volume rendered fluid, m3that is determined by the formula

Vresidence permit=V1-V2,

where V1- the volume of liquid filled laboratory setting, m3;

V2- the amount of liquid remaining in a laboratory setup, m3.

Low absolute carrying capacity due to the low content of non-ionic surfactants and high solubility of solid foam. We conducted laboratory tests showed that the ratio of initial components urea: nonionic surfactants from 0.7:1 to 1:1 by weight, respectively, is sufficient for curing most nonionic surfactants. An excess of urea, which is soluble surface-indifferentism substance, leads to the reduction of the absolute carrying capacity. From the content of nonionic surfactant is an active part of the solid foaming agent, which comprises from 10 to 50 wt.%, depends on the volume of liquid (Vresidence permit), which can be given (connected) unit mass (m) of the solid foaming agent. Low content of nonionic surfactants requires centuries is the origin of the greater mass of the solid foaming agent into the well for removal of the same amount of liquid, that reflects the low absolute carrying capacity. Enter more solid foaming agent is economically impractical. Upon contact of the solid foaming agent with the liquid components interact with the dipoles of water. Urea, quickly dissolving, leads to an increase in interfacial contact surface of the adduct of urea fluid. This significantly increases the dissolution rate of the solid foaming agent, which leads to reduction of the volume rendered fluid per unit mass of the solid foaming agent, as in the initial moment of time is formed solution with an excess concentration of nonionic surfactants, which are to be presented first portions formed foam upward flow of gas. Laboratory studies have shown that the dissolution rate was 0.05-0.1 m/h, at the rate of dissolution of the solid foaming agent can not reach areas of bubbling. Subsequently, this leads to excess solid foaming agent and reducing inter-operational period as the underlying layers and the new batch of liquid, which is within 0.3 to 1.0 hours can go into a well, will not be covered by the effect of nonionic surfactants. The efficiency of the process decreases not only due to cost overruns solid foaming agent, but also by reducing mega Aracinovo period of time, elapsed between two consecutive operations of the input solid foaming agent), as the process fluids in the well are often continuous and high rate of dissolution decreases the duration of the solid foaming agent.

In addition, this technology requires a significant investment of time, a large number of technological operations and equipment: the need for grinding granulated urea to a powder, and the finer fraction of urea, the faster and better the urea adduct is formed, keeping the original system in split forms within 24-48 hours, additional pressing of the adduct with the use of a press (e.g., hydraulic) in the presence of a lubricating agent;

as a prototype we have used a method of obtaining a solid foaming agent specified in the patent of Russian Federation №2100577 ot, CL EV 43/00, 37/00, publ. in ABOUT No. 36 dated 27.12.1997, "Solid foaming agent used to remove liquid from the gas and gas condensate wells. The method is carried out mixing nonionic surfactants: OP-10 or neonols brand AF-9, or a block copolymer and a derivative of carbonic acid, containing nitrogen, in the form of a mixture of complex salt of urea with an acid (hereinafter complex salts of urea: urea oxalate or nitrate urea or Hydra is chloride urea. Next produce molding the resulting mixture.

The choice of the prototype due to high concentration in the solid foaming nonionic surfactants to 57 wt.% or the ratio of parts by weight of components a derivative of carbonic acid containing nitrogen: nonionic surfactant of 1:0.52 to 1:2,28, respectively.

The disadvantage of this method is the following:

- low strength properties of solid foam. This is due to the impossibility of the formation of adducts between complex salts of urea and nonionic surfactants.

Figure 1 shows the structural formula of nitrate of urea.

Figure 2 presents the structural formula of urea oxalate.

Common to complex salts of urea is the structure of the internal sphere of the molecule - cation salts, which consists of complexing agents - isocyanato acid (HNCO) and ligands of the hydrogen ion (H+) and a molecule of ammonia (NH3). In the cation of the salt, the carbon atom is in the state of sp-hybridization and associated with one nitrogen atom and an oxygen atom double bonds, the angle of communications NCO is equal to 180°. Lone-electron pair of the nitrogen atom that is part of the ammonia molecule, forms, together with the carbon atom covalent polar bond in the donor-acceptor mechanism, the angle connection NCN 90°. In addition, in the molecule are strongly polarized atoms (N, O, what), ions (H+,, Cl-,), which leads to displacement (redistribution) electronic densities.

Considered (see Grandberg I.I. Organic chemistry: Textbook. For stud. Of higher educational institutions on an agronomist. spec. - 5th ed., the stereotype. - M.: bustard, 2002. - 672 S. and Curly V.I., Lebedev V.V. Synthesis and application of urea. - L.: Chemistry, 1970)that the corners of communication between the two nitrogen atoms and an oxygen atom close to 120°length relations With=O (0,126 nm) and C-N (of 0.133 nm), indicating a strong coupling in the molecule. This provides reactivity of molecules of urea to the formation of hexagonal spatial structure with the formation of stable adducts of urea.

When the above values of angles in molecules complex salts of urea formation of adducts between them and the nonionic surfactant is not happening. Thus, the components form a coarse heterogeneous mechanical mixture strength properties which are due to the presence of the physical adsorption interaction. Adsorption of nonionic surfactants - adsorbate on the surface of the complex salts of urea and nitrates of alkali and alkaline earth metals-adsorbents occurs due to dispersion (van der Waals) forces and electrostatic effect, increasing as a result of Ogorodnik links.

3 shows the structural formula of neonols brand AF-9.

Consider the distribution of electron density in the molecule of neonols brand AF-9.

The alkyl moiety and the hydrophilic portion of the molecule nonionic surfactant represented by the group of ethylene oxide (-CH2-CH2"Oh-)are the substituents of the 1st kind (positive induction effect) and tell the kernel benzene total increased electron density. The atoms of oxygen with greater affinity to the electron transport electron cloud, resulting in the carbon atoms is a partial positive charge. The decrease in electron density on the carbon atom causes an increase in the polarity of the connections of this atom with hydrogen atoms, resulting in increases their reactivity. While the hydrogen atoms become more active to the formation of hydrogen bonds to more electronegative atoms of the molecules of the adsorbent (N, O, Cl), which have a lone electron pair. Specific (interphase) surface is very poorly developed, the coupling strength physical adsorption interactions are small (energy 5-15 kJ/mol), as a result, they can easily break down when heated (desorption of surfactants), under the action of dissolved gas (gas corrosion), when interacting with polar solvents (water dipoles), etc. lab the lab studies have shown, the compressive strength was 0.4 MPa, a bending strength of 0.6 MPa (see table of instrument testing of the prototype). The moisture contained in the well (in natural gas), immediately begins to initiate the process gas. This complicates the use of solid foam in deep or inclined wells, because due to insufficient strength in the fall it can stick to the tubing to deform and start gassing. Similarly examines the interaction adsorbents with other nonionic surfactants;

- reduced the absolute carrying capacity of the solid foaming agent.

Reduced absolute carrying capacity of the prototype (of 0.21-0.26 kg/m3) is associated with an increase in the dissolution rate of the solid foaming agent. The kinetics of dissolution will be limited by the rate of heterogeneous reactions, which evolved gaseous products (N2, CO3) will destroy the structure of the solid foaming agent that will increase the interfacial contact surface of the solid foaming agent fluid and increase the dissolution rate. The highest dissolution rate leads to the decrease of the volume rendered fluid (Vresidence permit) per unit mass (m) of the solid foaming agent, as in the initial moment of time formed Astor excessive concentration of nonionic surfactants, which will be decided first portions formed foam upward flow of gas. This ultimately leads to excess solid foaming agent and reducing inter-operational period, as the new batch of liquid, which is within 0.3-1.0 hour can come into a well, will not be covered by surfactant action. The density of the solid foaming agent 1010-1030 kg/m3that is not much higher than the density of the liquid in the well, and the emitted gas will hold a solid foaming agent in the upper layers (confirmed by laboratory testing). Excessive concentration of nonionic surfactants in the upper layers of the liquid leads to intense emulsification of gas condensate and the emergence of a stable emulsion due to the formation of saturated adsorption layer of nonionic surfactants on the globules of gas condensate, which slows down the process of foaming. To revive the latter is possible only by introducing an additional quantity of solid foam.

In addition, the components included in the composition of the solid foaming agent, is highly hygroscopic. During storage, even in a sealed envelope solid foam loses its shape and uniform structure (gas corrosion), resulting strength properties are reduced. Individual substances included in the composition, require automatic is who control their content in the air of working zone (for example, sodium nitrite belongs to class I hazard beam mechanism of action). Mass production technology of solid foam complicated and requires much time.

The technical result that can be obtained by carrying out the present invention, is as follows:

- increase strength properties of solid foaming agent due to the formation of the crystalline structure;

- increase the absolute carrying capacity of the solid foaming agent through the acquisition of prolonged action to remove the liquid.

The technical result is achieved by means of well-known operations of the method: mixing nonionic surfactant and a derivative of carbonic acid, nitrogen-containing, and molding the resulting mixture. Thus according to the invention: as a derivative of carbonic acid, nitrogen-containing, use urea; it is additionally dissolved in water, heated to 50-90°With, in the ratio (parts by weight)equal to 9-10:1, respectively; heat the mixture before formation of a true solution; nonionic surfactant is heated to 40-80°C; mixed nonionic surfactants with the true solution of urea in the ratio (parts by weight), 1.0 to 1.4:1, respectively, before forming in the resulting liquid crystal mixture components on billaut water-soluble polymer in the ratio (parts by weight), equal to 1:0.01 to 0.05, respectively, or a mixture of water-soluble polymer and moderator dilution ratio (parts by weight) liquid crystal mixture components : a water-soluble polymer : moderator dilution of 1:0.01 to 0.05:0.4 to 0.6, respectively.

The inventive method corresponds to the condition of novelty.

As the use urea Urea grade B according to GOST 2081-92.

As the nonionic surfactants used neonol brand AF 9-12 on THE 2483-077-05766801-98 "Neonols", which is a technical mixture of polyethylene glycol ethers of monoalkylphenols of the following composition:

C9H19C6H4O(C2H4O)nH,

where C9H19is an alkyl radical of isononyl attached to the phenol predominantly in the para-position to the hydroxyl group;

n is the average number of moles of ethylene oxide attached to 1 pray ALKYLPHENOLS, equal 9-12,

OP-10 GOST 8433-81, representing the products of processing a mixture of mono - and dialkylphenols oksietilenom,

block copolymers of ethylene oxides and propylene in THE 38.507-63-09-89 General formula:

WithnH2n+1O(C3H6O)m(C2H4O)pN

where n is the number of carbon atoms in the alkyl radical, equal to 5-15;

m is the number of moles of ethylene oxide, equal 9-45;

p is the number of moles of propylene oxide, equal 30-180.

The action of these vases is in the solid foaming agent are identical.

As the water-soluble polymer used carboximetilzellulozu on THE 6-55-40-90, polyacrylamide AK-631 grade a-1510 on THE 6-02-00209912, polyvinyl alcohol, brand 18/11 according to GOST 10779-78 grade 1. The action of these substances in the solid foaming agent are identical.

As lignosulfonates use condensed sulfite alcohol bard (kssb 2) TU 39-094-75, condensed sulfite alcohol bard (kssb 5) TU 17-06-311-94, sulfite alcohol bard on THE 81-04-225-78. The action of these substances in the solid foaming agent are identical.

The water is heated to a temperature of 50-90°to produce dissolving urea in the minimum amount of time (to reduce losses of urea due to hydrolysis).

Hydrolysis occurs in 2 stages:

1. CO(NH2)2↔NH4OCN (isomerization in water of urea into ammonium cyanate)

2. NH4OCN+2H2About↔(NH4)2CO3

While the ammonium cyanate in aqueous solution dissociates to ions

NH4OCN↔+NCO-↔NH3↑+HNCO (solanova acid)

and that ions NCO-undergo hydrolysis

NCO-+2H2O↔+

Considered (see Curly V.I., Lebedev V.V. Synthesis and application of urea. - L.: Chemistry, 1970, p.114), that at length the flax heating system urea - water there are significant losses of urea due to its hydrolysis and irreversible excretion of ammonia. The kinetics of dissolution depends on the structure and size of solid particles of urea, type of solvent, the intensity of heating, the initial water temperature. Dissolving urea reaction is endothermic (heat of dissolution in water Q=57.8 cal/g). When the initial water temperature is below 50°With the urea granules are sintered (escalated) and the time to obtain the true solution of urea significantly increased. The increase in time of the dissolution of urea leads to increased losses last due to hydrolysis, which affects the strength properties of solid foam. When water temperature is above 90°high evaporation leads to water loss, it is also possible boil. That is, this operation significantly affects the kinetics of dissolution of urea and final technical result.

In heated water while stirring gradually fall asleep granulated urea in the ratio of parts by weight of 1:9-10, respectively. By reducing the water concentration of urea in the solution increases, the temperature of obtaining true solution of urea increases, the degree of hydrolysis, too, that adversely affects the strength properties of solid foam. With the increase with the holding water loss urea increased, resulting strength properties of solid blowing agents are reduced. Considered (see Curly V.I., Lebedev V.V. Synthesis and application of urea. - L.: Chemistry, 1970, S. 121)that the rate constant of isomerization (1st stage of hydrolysis depends on the initial concentration of urea and increases in direct proportion to the water content in the urea solution. When this hydrolysis and subsequent loss of urea increases, which affects the strength properties of solid foam. The amount of water taken more of the claimed ratio, may not be related additives and makes a solid foaming agent is looser, which negatively affect the strength properties of solid foam. The use of the claimed ratio of the urea - water can significantly reduce the transition temperature of the crystalline urea in the molecular state (melting point at atmospheric pressure 132,7° (C)to avoid thermal decomposition, as by melting, and use granulated urea without preliminary grinding, as specified in the analog. The choice of solvent is water due to several reasons: provides good solubility of the urea has low viscosity, readily available and cheap (unlike ethanol), non-toxic (unlike methanol and PI is Idina), easily associated additives (lignosulfonate and water-soluble polymers). The resulting mixture is used to produce a true solution of urea.

The mixture continue heating until all the urea has dissolved. When a predetermined ratio of urea and water, a saturated solution is obtained at temperatures of up to 104° (Curly V.I., Lebedev V.V. Synthesis and application of urea. - L.: Chemistry, 1970, s.431). A saturated solution is heated to a temperature of 106-109°, that is, to obtain the true solution. It is necessary for the implementation of favorable conditions when mixing to avoid premature precipitation of particles of the solid phase (crystals of urea). At temperatures below obtain the true solution may result in premature precipitation of particles of the solid phase (crystals of urea), which leads to an undesirable reduction of the surface interaction between the components and further reduce the absolute carrying capacity of the solid foaming agent. Molecules inside the crystals of urea, may remain unreacted, which reduces the amount of unreacted nonionic surfactants, they increase the rate of dissolution of the solid foaming agent. The heating of the urea solution above the temperature of obtaining true solution is not economically feasible and can lead to increased sweat the R urea due to hydrolysis, what affects the strength properties of solid foam. Obtaining the true solution of urea allows to overcome the energy barrier for the formation of the adduct of urea that is associated with the rebuilding of the molecules of urea in hex spatial structure (as urea in the true solution is in a molecular state). The energy stored (accumulated) in the form of energy of the fluid, which then goes to the heat of crystallization. When the interaction between the two substances is mutual physico-chemical adsorption of the two components with the formation of the complex compound (adduct of urea), and the more molecules involved in this process, the better and better it flows. The increase in the number of "active" molecules of urea leads to the maximum possible number of molecules of nonionic surfactants that can react, that is to form the maximum number of the adduct of urea. So getting the true solution is one of the main conditions for obtaining maximum technical result.

To ensure sufficient mobility and viscosity required for mixing the true solution of urea and nonionic surfactants, the latter is heated to 40-80°C. When the heating temperature nonionic surfactant is below 40°With Snicket severe hypothermia true solution of urea, what can cause the growth of large crystals, which affects the strength properties of solid foam. Heating nonionic surfactants above the temperature of 80°not economically feasible and positive change doesn't introduce, in addition, of nonionic surfactants can evaporate volatile substances, odorous and harmful to health.

Received hot liquid components are mixed by the mixer in the ratio of nonionic surfactants : the true solution of urea (parts by weight)of 1:1,0-1,4, respectively. When reducing the content of nonionic surfactant, the content of urea is increased, resulting in the absolute carrying capacity and strength properties of solid foaming agent is reduced. Urea, which is soluble surface-indifferent substance, leads to the reduction of the absolute carrying capacity. From the content of nonionic surfactant is an active part of the solid foaming agent is dependent on the volume of liquid (Vresidence permit), which can be made by unit mass (m) of the solid foaming agent. Lowering the content of nonionic surfactants requires the introduction of the greater mass of the solid foaming agent into the well for removal of the same amount of liquid, which subsequently leads to overspending solid foaming agent and reflects low until the running-absolute carrying capacity. With the increase of urea, the rate of dissolution of the solid foaming agent is increased and as a result, in the initial moment of time is formed solution with an excess concentration of nonionic surfactants, which are to be presented first portions formed foam upward flow of gas. The efficiency of the process decreases not only due to cost overruns solid foaming agent, but also by reducing the holding period, as the process fluids in the well are often continuous and high rate of dissolution decreases the duration of solid foam. The increase of urea, which is anisotropic crystalline substance, gives a solid foaming agent fragility (bending strength is reduced), which can lead to the destruction of the solid foaming agent during transportation or falling into the well. The increase in the content of nonionic surfactants affects the strength properties of solid foam. The resulting solid foam becomes more plastic (compressive strength decreases), because this amount of urea is not sufficient for curing nonionic surfactants. At this stage there is a formation of the adduct of urea. The formation of the crystalline structure is due to the fact that the formation of aldactoneonline is from a system with high specific surface area of contact between the components with the condensation of (the creation of supersaturation). Due to the high specific surface area of contact of the components of the mixture process of physico-chemical adsorption interaction between the molecules of urea and nonionic surfactants with the formation of the adduct of urea proceeds evenly, quickly and completely. When the injection of nonionic surfactants of the true solution of urea is a small cooling of the latter, which is the driving force of the crystallization process. Since the internal energy of the liquid is higher than an ordered solid, the crystallization process is accompanied by heat release. The temperature of the mixture is increased, which prevents the formation of large crystals of the adduct of urea. The emergence of heterogeneous crystals as "active" molecules of urea due to mutual physico-chemical adsorption of molecules of nonionic surfactant to form a large number of crystals of the adduct of urea in the whole volume of the mixture. Each molecule of nonionic surfactants in essence can be considered as an active center of crystallization, as it has a lower temperature than the molecules of urea, thereby creating a saturation around. In the "active" molecules of urea, which is in close proximity, we give part of our internal energy, moving into the crystalline state, form a hexagonal spatial structure is ur around molecules nonionic surfactants, that is, they form an adduct of urea. In addition, the technical components may contain impurities, i.e. additional crystallization centers.

The result is a liquid crystal mixture consisting of a large number of small crystals of the adduct of urea throughout the volume, which positively affects the crystallization mixture is formed of the crystalline structure and strength properties of solid foaming agent.

In the obtained liquid mixture was added water-soluble polymer in the ratio of parts by weight of 1:0.01 to 0.05, respectively, or a mixture of water-soluble polymer and moderator dilution in the ratio of parts by weight of the liquid crystal mixture components : a water-soluble polymer : moderator dilution of 1:0.01 to 0.05:0.4 to 0.6, respectively. When reducing the content of water-soluble polymer reduced the absolute carrying capacity, strength properties of solid foam deteriorate as the water may remain unbound. The increase in the content of water-soluble polymer increases the viscosity of the foam, which affects the absolute carrying capacity of the solid foaming agent (transporting function of the foam is reduced), it is also not economically feasible. Reducing a water-soluble polymer and dissolution retarder is designed for people who is absolute carrying capacity, since the dissolution rate increases. The increase in the content of water-soluble polymer and moderator dissolution leads to the fact that the produced mixture is very difficult to shape, the absolute carrying capacity of the solid foaming agent is reduced due to the increased viscosity of the foam (transporting function of the foam is reduced), which may lead to an increase in hydraulic resistance in the pipeline. The most negative influence on the viscosity of the foam has a water-soluble polymer, a dissolution retarder significant influence on the rheological properties of foams is not provided, but in excess it difficult molding. Water-soluble polymer and the dissolution retarder enhance strength properties (bind free water, forming a single structure) and improve the absolute carrying capacity of the solid foaming agent, so as to reduce the rate of dissolution of the latest and contribute to the process of emulsification of gas condensate and stabilize the foam. Water-soluble polymer and the dissolution retarder also serve as additional crystallization centers that contribute to the formation of the crystalline structure.

In formulating serves mixture which is extruded in a plastic shell of the required diameter and length. The formed mixture podesiv who are in a vertical position to avoid deformation, which when cooled completely crystallizes and hardens. Due to the fact that the moldable mixture has a large number of crystals of the adduct of urea throughout the volume, then cooled and the final crystallization is formed of a single solid crystalline structure.

High strength properties are of great importance in transportation and in the process of entering the solid foaming agent into the well. When falling from the top of the lubricator to the locking wedge buffer latches (a distance of about 1.0-1.5 m) and hits the wall of the lift pipes of solid foam with insufficient bending strength (brittle) can be scattered, losing a single structure and not to reach the accumulated liquid. In addition, most of the wells in operation, deep and sloping, solid foam with insufficient compressive strength (plastic) can be deformed and to stick to the tubing, which can cause high hydraulic resistance in the tubing. Therefore, the high strength properties are an important indicator of the solid foaming agent.

Reaching liquid, solid foaming agents interact with the dipoles of the water and begin to dissolve. Dissolution is slow, therefore, honey is i.i.d. released nonionic surfactants, that allows you to maintain the concentration of the foaming agent at the level of the critical concentration of micelle formation for a long period of time, while receiving the maximum amount of foam, i.e. the amount of delivered fluid (Vresidence permit) the unit mass of the solid foaming agent (m). Emulsification of gas condensate is the initial and crucial step of foaming gas condensate mixtures. Adsorption of nonionic surfactants on the surface of gas condensate leads to the formation of hydrophilic emulsion (dispersion medium is an aqueous solution and two dispersive phase - gas and gas condensate). The activity of nonionic surfactants in mineralized water is not reduced, since the complexes are formed with ions of calcium and magnesium. These complexes adsorbed on the phase boundaries, form strong adsorption layer nonionic surfactants. In addition, in education take part water-soluble polymers and lignosulfonates (moderator dissolution)that strengthens adsorption layer of emulsifier, thereby increasing the absolute carrying capacity of the solid foaming agent.

Before entering the solid foaming agent into the well to perform interval measurements of pressure and temperature instruments, determine its performance and the amount of delivered gas liquids. After the data analysis of raschityvat the t required quantity of solid foaming agent for the complete removal of the accumulated in the borehole fluid.

The number entered into the well of the solid foaming agent depends on the amount of the accumulated liquid, the content of nonionic surfactants in solid foaming agent, and mixtures of the latest and calculated by the formula:

where n is the number of terminals of the solid foaming agent required to remove the liquid, units;

VW- the volume of accumulated fluid in the column lift pipes and perforation interval, m3;

νathe absolute carrying capacity of the solid foaming agent, m3/kg;

and the content of the nonionic surfactant in the solid foaming agent, wt.%;

m is the mass of one of the solid foaming agent, kg

It follows that the increase in the absolute carrying capacity reduces the amount of solid foam required to remove liquid from the wells. Insufficient amount of solid foam may cause part of the liquid in the well, will not put. Excess amount of solid foam slows conclusion well in normal mode, as this forms a viscous foam that creates a high resistance to gas flow in the tubing.

Based on the analysis of patent documents and scientific literature we are not the first who Lena operation or set of distinctive parts of the claims of the method of obtaining a solid foaming agent to remove liquid from the wells, performing functions similar to those of the claimed technical result. In this regard, we believe that the proposed solution involves an inventive step.

For testing was chosen problematic well Yamburg gas condensate field No. 101.3 - vertical. Mineralization is removed from the well water - 2564,33 mg/l (Ca2++Mg2=70 mg/l). The amount of liquid (VW) is equal to 0.78 m3the weight of one of the solid foaming agent is 0.6 to 0.7 kg, the content of nonionic surfactants 47,6-57.8 wt.% (in solid foam using water-soluble polymer) and 35.4 is 41.4 wt.% (in solid foam using water-soluble polymer and dissolution retarder). According to the formula calculated and introduced optimum amount of solid foam (1 pc. using a water-soluble polymer, 2 pieces using a water-soluble polymer and dissolution retarder). To prevent the freezing of wellhead and tubing used hard foam with a diameter of 50 mm and a length of 400 mm At the solid foam accumulated liquid was completely removed, the resulting increase in flow rate of gas 155 thousand m3/day.

In more detail the essence of the proposed technology described by the following examples.

Example 1.

Urea in the amount of 117 g (9 parts by weight) is astonaut 13 g (1 parts by weight) water, heated to 50°C. the resulting mixture was continued to be heated to obtain the true solution of urea (106°). Next neonol in the amount of 182 g (of 1.4 parts by weight) is heated to 60°and mixed with 130 g (1 parts by weight) of the true solution of urea. Get the liquid crystal mixture. Mix 312 g (1 parts by weight) liquid crystal mixture and 3.1 g (0.01 to parts by weight) of polyacrylamide. Molded resultant mixture and squeeze in a plastic shell length of 16 cm and a diameter of 5 cm

Test the obtained solid foaming agent as specified in the act laboratory tests. The absolute carrying capacity of 0.65 m3/kg, the compressive strength of 1.1 MPa, bending to 2.2 MPa.

Example 2.

Urea in the amount of 130 g (10 parts by weight) is dissolved in 13 g (1 parts by weight) of water, heated to 60°C. Next, the operation is carried out as described in example 1. OP-10 in the amount of 172 g (1,2 parts by weight) is heated to 50°and mixed with 143 g (1 parts by weight) of the true solution of urea. Get the liquid crystal mixture. Mix 315 g (1 parts by weight) liquid crystal mixture and 9.4 g (of 0.03 parts by weight) of polyvinyl alcohol. Next, perform the operation as described in example 1.

The absolute carrying capacity of 0.53 m3/kg, the compressive strength is 1.0 MPa, Flexural strength of 2.1 MPa.

Example 3.

Urea in the amount of 135 g (9 parts by weight) dissolved in 15 g (1 parts by weight) of water, heated to 70°C. Then hold the peratio so, as indicated in example 1. Next, the operation is carried out as described in example 1. Block copolymer of ethylene oxide and propylene in the amount of 150 g (1.0 parts by weight) is heated to 70°and mixed with 150 g (1 parts by weight) of the true solution of urea. Get the liquid crystal mixture. Mix 300 g (1 parts by weight) liquid crystal mixture and 15.0 g (0.05 parts by weight) of carboxymethyl cellulose. Next, perform the operation as described in example 1.

The absolute carrying capacity of 0.55 m3/kg, the compressive strength of 1.7 MPa, bending to 3.7 MPa.

Example 4.

Urea in the amount of 99 g (9 parts by weight) dissolved in 11 g (1 parts by weight) of water heated to 80°C. Next, the operation is carried out as described in example 1. OP-10 in the amount of 110 g (1.0 parts by weight) is heated to 40°and mixed with 110 g (1 parts by weight) of the true solution of urea. Get the liquid crystal mixture. Mix 220 g (1 parts by weight) liquid crystal mixed with 2.2 g (0.01 to parts by weight) of polyacrylamide and 88.0 g (of 0.4 parts by weight) kssb - 2. Next, perform the operation as described in example 1.

The absolute carrying capacity of 0.60 m3/kg, the compressive strength of 2.0 MPa, bending and 3.4 MPa.

Example 5.

Urea in the amount of 90 g (10 parts by weight) dissolved in 9 g (1 parts by weight) of water, heated to 90°C. Next, the operation is carried out as described in example 1. Block copolymer of ethylene oxide and propylene in the amount of 119 g (with 1.2 parts by weight) is heated to 80°and smeshivayte 99 g (1 parts by weight) of the true solution of urea. Get the liquid crystal mixture. Mix 218 g (1 parts by weight) liquid crystal mixture of 6.5 g (0.03 in parts by weight) of polyvinyl alcohol and 108,9 g (0.5 parts by weight) kssb - 5. Next, perform the operation as described in example 1.

The absolute carrying capacity of 0.57 m3/kg, the compressive strength is 2.2 MPa, bending and 5.6 MPa.

Example 6.

Urea in the amount of 80 g (10 parts by weight) is dissolved in 8 g (1 parts by weight) of water, heated to 70°C. Next, the operation is carried out as described in example 1. Neonol in the amount of 123 g (of 1.4 parts by weight) is heated to 60°and mixed with 88 g (1 parts by weight) of the true solution of urea. Get the liquid crystal mixture. Mix 211 g (1 parts by weight) liquid crystal mixture of 10.6 g (0.05 parts by weight) of carboxymethyl cellulose and a 126.7 g (to 0.6 parts by weight) of the PRS. Next, perform the operation as described in example 1.

The absolute carrying capacity of 0.66 m3/kg, the compressive strength of 1.8 MPa, Flexural strength of 3.6 MPa.

Actually see the exceeding of technical performance of solid foam obtained by the present technology on the performance of solid foam obtained by the prototype.

Thus, the claimed technical solution meets the conditions of novelty, inventive step and industrial applicability, i.e. it is patentable.

1. A method of obtaining a solid foaming agent for removal of liquid is from gas and gas condensate wells, comprising mixing a non-ionic surfactant surfactant and a derivative of carbonic acid, nitrogen-containing, and molding the resulting mixture, characterized in that as a derivative of carbonic acid, nitrogen-containing, using urea, which is optionally dissolved in water, heated to 50-90°With, in the ratio (by mass)equal 9-10:1, respectively, followed by heating the mixture to obtain the true solution, and the nonionic surfactant is heated to 40-80°and mixed with the true solution of urea in the ratio (parts by weight), 1.0 to 1.4:1, respectively, and before the molding of the resulting liquid crystal mixture components add water-soluble polymer in the ratio (by mass)is 1:0.01 to 0.05, respectively, or a mixture of water-soluble polymer and moderator dilution ratio (parts by weight) liquid crystal mixture components: a water-soluble polymer: moderator dilution of 1:0.01 to 0.05:0.4 to 0.6, respectively.

2. The method according to claim 1;characterized in that as the nonionic surfactants used reagents selected from the group: neonol, OP-10, block copolymers of ethylene oxides and propylene.

3. The method according to claim 1, characterized in that as the water-soluble polymer used reagents selected from the group of: carboxymethylcellulose, polyacrylamide, polyvinyl with the RTI.

4. The method according to claim 1, characterized in that as a moderator dissolution using lignosulfonates.



 

Same patents:

FIELD: mining industry.

SUBSTANCE: invention preferably relates to treatment of water-supply wells exposing sand producing formation and producing drinking, mineral, and industrial waters, mineral solutions, etc. Solid reagent used in this operation contains 37.5-73.2% of nitric acid/urea reaction product and 24.4-61.5% of oxygen-containing sulfur compound, the rest being sodium polyphosphate. Process solution, which is 10-30% solution of above-indicated solid reagent, is supplied to well provided with filter descended by means of tubing string, injected into formation through reagent conduit, and held in formation during a certain time, after which the well is pumped through. When process solution is held in formation, it is made to reciprocate with the aid of compressed air periodically injected to pressure-sealed wellbore, after which wellbore is depressurized. During the period of time when compressed air is injected, level of fluid in wellbore is lowered below static level at a distance not exceeding length of filter and time point when fluid reaches lower end of the filter is recorded. When this time point is stabilized, reciprocation of process solution is ended. When performing subsequent pumping of well, specific electrical resistance value of fluid pumped out of well is also measured and, when this value approaches or attains the value of specific electrical resistance of the formation fluid, pumping is terminated.

EFFECT: increased dissolving capacity of solid reagent for dehydrated ferruginous mudding deposits and prevented subsequent deposition thereof within near-filter zone, enhanced treatment efficiency due to increased permeability near-filter zone of formation, and intensified dissolution of mudding deposits.

6 cl, 6 tbl, 2 ex

FIELD: oil and gas production.

SUBSTANCE: complex reagent contains 88.9-90.1% poly(vinyl acetate) dispersion, 0.9-2.22% nitrilotrimethylphosphonic acid, 4.44-4.50% dibutyl phthalate, and 4.44-4.50% ethylene glycol.

EFFECT: improved strength and adhesion properties of grouting mortar.

1 tbl

FIELD: oil industry, particularly non-uniform reservoir development.

SUBSTANCE: method involves injecting isolation composition namely Portland cement dispersion and water-soluble polymer in well, wherein the components are taken in proportion of 1:(0.01-0.5) in oil-bitumen product, 5-56 parts by weight of Portland cement and water-soluble polymer are taken for 100 parts by volume of said dispersion; injecting aqueous Portland cement solution along with said dispersion, wherein the solution is taken in proportion of (0.1-0.5) per 1 part of said dispersion.

EFFECT: increased efficiency of stacked oil pool development and highly-permeable watered reservoir zones isolation.

2 cl, 3 tbl, 3 ex

FIELD: oil and gas production.

SUBSTANCE: invention relates to technological compositions used for increasing permeability of productive seams by carrying out hydrorupture of seam and can be used in extraction of gas and oil. Proposed liquid for hydraulic rupture of seam comprises the following components, wt.-%: potassium chloride, 6.00-7.00; sulfacell of sort 800, 1.30-2.00; aluminum sulfate, 0.15-0.80; disolvan, 0.03-0.05, and water, 90.15-92.52. Invention provides deceasing filtration, enhancing sand-retaining capacity, retention of filtration indices of critical zone of seam, availability of chemical reagents.

EFFECT: improved and valuable technical properties of liquid.

2 tbl

FIELD: petroleum-extracting industry.

SUBSTANCE: invention relates, in particular, to development of viscous-elastic liquids as sand-carriers for hydraulic disruption of low-penetrable gas- and oil-carrying seams in order to enhance their oil output. Proposed cross-linked liquid as sand-carrier based on hydrocarbon liquid and gel-forming agent comprises as a gel-forming agent a mixture of complexes of lithium tert.-butyltrialkyl borates - K [t-C4H9OB(OR)3]Li wherein R means (C4-C12)-alkyl, and a solvating agent - CA in the mole ratio K : CA = (1:1)-(1:2). As components of a gel-forming agent it comprises fraction of B(OR)3 wherein R means (C4-C12)-alkyl, and lithium tert.-butylate t-C4H9OLi in their mole ratio = 1:1, and in the following ratio of these components, wt.-%: trialkyl borates, 0.5-10.0; lithium tert.-butylate, 0.2-2.5, and hydrocarbon liquid, the balance. CA represents a compound of the following classes: saturated alcohol ROH, dialkyl esters R2O, primary H2NR, secondary HNR2, and tertiary alkylamines NR3 wherein R means (C4-C12)-alkyl. Invention provides expanding assortment of gel-forming agents, improvement of technological effectiveness of process in preparing liquid and enhancing its thermosedimentation stability.

EFFECT: improved and valuable properties of liquid.

3 cl, 3 tbl, 34 ex

FIELD: gas and oil production industry.

SUBSTANCE: invention relates to chemical compositions used in treatment of holes, among them absorbing holes, for decreasing hydrogen sulfide content in gaseous space in carrying out repairing, research and other works. Invention proposes a solid-phase composition for hydrogen sulfide neutralization that comprises the following components, wt.-%: surfactant, 0.5-7.4; polyvinyl acetate, 26.6-5.7 and water glass, 2.6-4.6 as reagent-stabilizing agents of foam, and sodium nitrite and sulfamic acid taken in stoichiometric ratio with respect to each component in reaction with hydrogen sulfide, the balance. Proposed composition can be used in gas and oil production industry under normal and low seam pressures. Invention provides development of effective and simple in preparing and technological composition used in neutralization of hydrogen sulfide in holes, enhancing neutralizing activity of hydrogen sulfide neutralizing agent with respect to hydrogen sulfide in seam space both in gaseous and dissolved state.

EFFECT: improved and valuable properties of composition.

6 tbl, 1 ex

FIELD: gas and oil production industry.

SUBSTANCE: invention relates to chemical composition used in treatment of holes, among them, absorbing holes, for decreasing the content of hydrogen sulfide in gaseous space in carrying out repairing, research and other works, and can be used in gas and oil production industry under conditions of normal and low seam pressures. Proposed composition comprises the following components, wt.-%: sodium peroxocarbonate, 10-40; surfactant (surface-active substance), 0.5-10; polyacrylamide, 0.02-0.1; sulfamic acid, 17-53, and sodium nitrite, 21-52. The slid-phase composition can comprise water glass also. Invention provides development of effective and simple in preparing and technological composition used for neutralization of hydrogen sulfide in holes.

EFFECT: improved and valuable properties of composition.

2 cl, 7 tbl, 2 ex

FIELD: oil and gas extracting industry.

SUBSTANCE: invention relates to damping holes in their overhaul repair. Proposed technological liquid used in damping oil and gas holes comprises the following components, wt.-%: microbial xanthane biopolymer, 0.5-2.0; modified starch, 0.2-2.5; surfactant (surface-active substance), 0.01-0.2; sodium carbonate, 0.1-1.0; aluminum power, 0.005-0.08, and water, the balance. Method for preparing indicated aphron-containing technological liquid used in damping oil and gas holes involves mixing its components to obtain two solution wherein one solution contains sodium carbonate and surface-active substance obligatory, and other solution contains aluminum powder. Mixing these solution is carried out at temperature from 50°C to 90°C. Invention provides preparing aphron-containing liquid for damping under static conditions without using special gas-dispersing equipment and based on available reagents.

EFFECT: improved and valuable technical properties of liquid.

2 cl, 3 tbl, 3 ex

Grouting mortar // 2322471

FIELD: gas and oil industry.

SUBSTANCE: invention relates to grouting mortars used in cementing casing strings in gaseous, gas-condensate or petroleum holes in zone of productive seam at moderate temperatures. Proposed grouting mortar comprises the following components, wt.-%: grouting Portland cement, 64.41-66.24; sulfacell, 0.13-0.40; microsilica MK-85, 0.33-1.99, and water, 33.20-33.30. Invention provides preparing grouting mortar of reduced water yield in face conditions and with simultaneous enhance of strength of cohesion of cement stone with a casing string.

EFFECT: improved and valuable properties of grouting mortar.

1 tbl, 1 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to synthesis of unknown early N-[alkylphenoxypoly(ethyleneoxy)carbonylmethyl]-morpholinium chlorides. Invention proposes novel compounds - N-[alkylphenoxypoly(ethyleneoxy)carbonylmethy]-morpholinium chlorides of the general formula: wherein R means aliphatic hydrocarbon radical comprising 8-12 carbon atoms; n means an average degree of oxyethylation equal to 3, 6, 7, and a method for synthesis of these compounds. Synthesized compounds possess property of inhibitors of asphalt-resin-paraffin deposits and can be used in oil industry for prevention of precipitation of asphalt-resin-paraffin deposits from the oil in its extraction, preparing and transporting.

EFFECT: improved and valuable properties of compound.

2 tbl, 7 ex

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

Drilling mud // 2268909

FIELD: drilling wells; water-base drilling muds.

SUBSTANCE: drilling mud contains the following components, mass-%: clay, 1.5-3.0; carboxymethyl cellulose, 0.1-0.3;carboxymethyl starch, 0.75-1.5; mixture of ethers and amides of fatty acids and ethanol amides, 0.75-1.0; product of rectification of propylene oligomers of isoolefin type, fraction C13-C15, 0.75-1.5;lubricating additive, 0.5-3.0; the remainder being water.

EFFECT: enhanced inhibition ability of drilling mud at improved technological parameters.

2 tbl, 3 ex

FIELD: oil and gas production.

SUBSTANCE: invention relates to drilling fluids used when boring oil and gas wells. Lubricating additive contains 10-30% tall oil, 15-20% polyglycols, 40-50% oxal flotation reagent, and 15-20% beet molasses.

EFFECT: increased stabilizing, lubricating, and antiwear properties of drilling fluid.

2 tbl, 2 ex

FIELD: oil and gas production.

SUBSTANCE: invention relates to oil production technology involving use of hydrochloric acid-based chemicals via complex hydrochloric acid effect on well bottom zone to intensify oil production and may be specifically used to increase oil recovery of viscous oil-saturated low-permeable carbonate reservoirs. Composition contains 22-28% of 20 vol % aqueous HCl solution, 7-8% of 98% aqueous acetic acid solution, and 65-70% of solvent based on light pyrolysis tar obtained as secondary product from petroleum processing enterprises.

EFFECT: increased well bottom zone treatment efficiency due to improved quality of treatment composition, in particular stability and dipping depth into formation.

4 tbl

FIELD: lubricants and boring engineering.

SUBSTANCE: multiple-purpose reagent containing lubrication-and-stabilization component (70-80%) and solvent (20-30%) contains, as said lubrication-and-stabilization component, oxidized mixture of paraffins, naphthenic and aromatic hydrocarbons at ratio 2:3:4, and, as said solvent, diesel fuel or kerosene.

EFFECT: improved lubrication properties of viscous-plastic drilling fluids and stabilized inverted emulsions used in boring operation and in pullout of hole.

2 cl, 2 tbl, 6 ex

FIELD: lubricants and boring engineering.

SUBSTANCE: multiple-purpose reagent containing lubrication-and-stabilization component (70-80%) and solvent (20-30%) contains, as said lubrication-and-stabilization component, oxidized mixture of paraffins, naphthenic and aromatic hydrocarbons at ratio 2:3:4, and, as said solvent, diesel fuel or kerosene.

EFFECT: improved lubrication properties of viscous-plastic drilling fluids and stabilized inverted emulsions used in boring operation and in pullout of hole.

2 cl, 2 tbl, 6 ex

FIELD: oil and gas production.

SUBSTANCE: invention provides water-based solid phase-free biocationic drilling fluid with density 10-70-1520 kg/m3. Drilling fluid contains 10-60% of a cation spectrum, namely calcium and sodium chlorides, and 0.1-2% of polymer additive, in particular xanthane series biopolymer.

EFFECT: improved wall-plastering and lubrication properties.

2 tbl

FIELD: petroleum-gas-extracting industry.

SUBSTANCE: invention relates to materials used for cementing oil, gaseous, gas-condensate and geothermal holes under conditions of saline and hydrogen sulfide media. The salt-saturated plugging composition for high-temperature holes comprising a binding agent and sodium chloride includes additionally swollen vermiculite sand of fraction 0.3-2.5 mm in the following ratio of components, wt.-%: binding agent, 85-90; sodium chloride, 8-10; swollen vermiculite sand of fraction 0.3-2.5 mm, the balance. Invention provides preparing impermeable cement stone with enhanced coupling strength with a column in the range of temperatures 50-110°C.

EFFECT: improved properties of composition.

1 tbl

FIELD: petroleum and gaseous industry.

SUBSTANCE: invention relates to drilling oil and gaseous wells, in particular, to polymer-clay fluids for drilling used under conditions of permafrost rocks. Proposed polymer-clay fluid shows the improved pseudoplastic properties providing enhancing retaining and transporting capacity and treatment degree of the well walls, diminished filtration due to high rate in formation of low-penetrable filtration crust preventing the well pollution and promoting to retention of its collector properties, reduced rate of warming up of permafrost rocks that prevents formation of caverns and destruction of the well walls and as result provides prolonged retention of the well trunk in the stable state. Polymer-clay fluid for wells drilling in permafrost rocks doesn't freeze at negative temperatures and comprises clay, stabilizing agent as a mixture of polysaccharide reagent and structure-forming agent, hydrocarbon antifreeze and water. As a polysaccharide reagent the polymer-clay fluid comprises Acinetobacter sp. biopolymer, and as a structure-forming agent it comprises condensed sulfite-alcohol distillery grains in the following ratio of components, wt.-%: clay, 6-8; condensed sulfite-alcohol distillery grains, 4-6; Acinetobacter sp. biopolymer, 2-4; hydrocarbon antifreeze, 7-19, and water, the balance, wherein the ratio of Acinetobacter sp. biopolymer and condensed sulfite-alcohol distillery grain = 1:(1-3) mas. p., respectively. As hydrocarbon antifreeze, polymer-clay fluid comprises carbamide or glycerol. Invention provides enhancing effectiveness in drilling of wells in permafrost rocks.

EFFECT: improved properties of polymer-clay fluid.

2 cl, 15 ex

FIELD: oil and gas industry, particularly flowing well killing for underground repair and overhaul performing.

SUBSTANCE: method involves blocking perforation interval and part of well bottom zone by replacing well fluid with blocking fluid and killing liquid arranged over the blocking one. Free gas is removed from well before blocking fluid delivery to well bottom. Necessary liquid level at well head is provided by well operation stoppage for a certain time, which provides termination of formation fluid degassing in well bore and free gas lifting to well head. Tube space and hole annuity is filled with liquid in several steps along with discharge of gas portions. Gas portion discharge may not result in formation fluid rise inside well bore to level of formation fluid degassing. Density of liquid to be added in tube space and hole annuity provides well filling to head thereof. Well killing liquid comprises industrial magnesium chloride, alkali or alkaline-earth metal hydrate, alkali metal carbonate and pore sealant, for instance cacao-bean pods and fresh water taken in predetermined ratio.

EFFECT: increased efficiency, possibility to kill wells characterized by abnormally high permeability of production bed and high gas factor.

2 cl, 1 ex

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