RU2376454C2 - Nano-wave method of bottom hole zone treatment, equipment and pressure multiplier - Google Patents

Abstract

FIELD: oil-and-gas production.

SUBSTANCE: invention related to oil-and-gas production, particularly to methods and equipment of bottom hole zone - BHZ treatment using target chemical reagents hydrodynamic action in infra-frequent and supersonic vibration spectrum. Pressure multiplier with nano-generator consist of connected with tubing string - TS case, with suction chamber, central canal for hydraulic connection to depression impulse generator -DIG and lateral and axial canals for connection with pressure accumulation chamber, formed by case and piston, supported by block of plate strings, installed on a stop block which fixed together with piston via adapter to cantilever part of case over DIG interconnection pipe, on the case and piston circular shaped nozzles installed opposite to each other, in its counterbore holes rigid fixed with possibility of pair contact at pistons initial position installed cylindrical elements made of piezoceramics. Equipment for nanowave bottomhole zone treatment, which includes TS, a jet pump installed on it, bellow which serially installed parker, mentioned above pressure multiplier, with a possibility of uplifting along the well, and depression impulse generator, which radial canals located on the same level as bottom perforation holes of the well perforation interval. Method of BHZ treatment using equipment mentioned above includes pumping in through hole clearance of a active reagent media into BHZ and further into reservoir, process ageing until deposits of asphalts, resins, and paraffins - DARP dissolved, other calmative deposits and withdrawal of generated passive media, hydroimpuls interval BHZ treatment with active reagent liquid media and final removal mentioned above passive media, at that DARP dissolver pumped in and acts as a active media, other calmative deposits with replacement killing fluid simultaneously performing depressive-repressive treatment, interval BHZ treatment performed by killing fluid with adding pf of water-repellent SAS for production well and hydrophilic SAS for injection well.

EFFECT: increase of oil and gas wells production, well injection capacity increase for injection wells, bottom hole zone recovery and initial permeability increase.

3 cl, 1 ex, 6 dwg

Description

The invention relates to the oil industry, specifically to methods and devices for processing bottom-hole formation zones - PZP using the hydrodynamic effects of target chemicals in the infra-frequency and ultrasonic vibration spectra.

There is a known method of processing the PPP, including the descent of tubing to the bottom of the tubing, pumping the processing compound along them, raising the pipes to the surface, lowering the ultrasonic waves emitter against the treated interval of the formation, and treating the formation with ultrasound in the medium of this composition, this pre-treatment of the formation carry out the perforation of the casing in the interval of the reservoir and in the environment of the processing composition, and ultrasonic treatment of the formation is carried out upon receipt of the processing first composition into the formation, and then from the formation into the well (RF patent No. 2108452, publ. 04/10/1998).

A significant drawback of this method, from an economic point of view, is the additional shooting of the formation - perforation of the casing string. In addition, there can be no talk of any wave loading or unloading of wells in the case of high injectivity of the wells, since it is practically impossible to implement it without depression on the formation. Also, this method does not allow, without additional descent, lifting the equipment to remove the products of destruction of asphalt-resin-paraffin deposits - paraffin deposits and clogging impurities, which will naturally reduce the processing efficiency.

A device is known for magnetic oil processing to prevent paraffin in tubing and pipelines. The device consists of a ferromagnetic pipe and at least two ring magnets located along it, each of which is composed of adjacent to the inoperative surfaces of the rod permanent magnets, and the magnet is made of two half rings magnetized radially opposite, and is installed between the ferromagnetic pipe for the passage of fluid close to them the main surfaces. The conducted operational tests of prototypes of devices in oil wells showed their high efficiency in terms of preventing the deposition of paraffin deposits and, as a result, an increase in the inter-flushing periods of the operation of downhole equipment (RF patent No. 2198849, publ. 02.20.2003, Bull. No. 5).

However, this device cannot be used to prevent the formation of paraffin deposits in the PPP or their destruction during repair operations.

Closest to the claimed is a method of reagent-pulse impact on the well and reservoir and installation for its implementation. In this method, which includes supplying an active liquid medium through the pressure multiplier - AHS to the sub-packer zone of the well and then into the formation system, followed by a pulsed action on the liquid medium, supply of the AHS to the nozzle of the inkjet apparatus and pumping out the passive liquid medium from the formation zone - ПЖС, as AJS use a mixture of aliphatic and aromatic hydrocarbon solvents with the addition of a treated demulsifier, AJS are crushed into the reservoir at a pressure of 10-20 MPa, hold for 12-24 hours, remove the AES from the wave of a heavy well with a pulse-wave depressive action in two modes, then, using a pressure multiplier with a flat-blasting head, a hydroimpulse time-dependent processing of the bottom-hole zone is carried out with technological fluid TJ with flat fan jets with a pulse frequency of 50-300 per min and a pressure value of 1.5-2.5 static pressure in the well at the level of the formation, after which the final removal from the formation zone of the PZhS is carried out, a solution of multifunctional surfactants is used as TZ. In this case, the installation comprises a tubing string, an inkjet apparatus installed on it with an active nozzle, a mixing chamber, a diffuser, supply channels of the AHS and PZhS, a packer sequentially placed under the inkjet apparatus, a pressure multiplier located below the perforation of the reservoir, with the possibility of its stepwise rise, where the jet apparatus is made dual-mode, the multiplier is equipped with a flat-jet head in its lower part, and the installation is additionally equipped with a depression a pulse generator and a pulse-wave depressor mounted on the earth’s surface, consisting of a discharge chamber connected to the annular space, in which a spring-loaded sleeve and a plunger are mounted with the possibility of displacement and locking, driven by a hydraulic cylinder with a spring-loaded piston with the possibility of closing the piston cavity with a hydraulic lock with control from the control valve with a feed from a hydraulic pump connected to the tank, and the discharge chamber has a drainage free hydraulic outlet in a drain tank (RF patent No. 2275495, Cl. ЕВВ 37/06, publ. 2006, Bull. No. 12).

The aforementioned method and device for reagent-pulsed impact on the reservoir of oil wells can increase the injectivity of injection wells, restore the initial injectivity of the bottomhole formation zone and increase the productivity of production wells. At the same time, loading ATZH through the tubing in dynamic mode requires a very high-quality packer fit, which is not always possible due to the casing string deformation and its ASPO walls overgrowing. In addition, for wells with high injectivity and low reservoir pressure, the wave unloading operation is problematic. Unfortunately, the proposed complex of technological equipment also does not allow to carry out such an important final operation as additional injection of hydrophilizing or hydrophobizing surfactant solutions without additional descent and ascent.

The objective of the invention is to increase the productivity of oil and gas condensate wells, to increase the injectivity of injection wells, to restore and increase the initial permeability of the bottom hole due to the phased application of chemical reagents conducted in the capillary array of the reservoir by capillary flows under the influence of nanowaves created by a special nanogenerator, as well as the simultaneous hydrodynamic effect of reagents infra-frequency spectrum of oscillations.

The problem is solved in that in the method of treating the bottom-hole zone of the formation — PZP, which includes injecting the active reagent liquid medium through the annulus into the PZP and further into the formation, withstand for destruction of the asphalt-resin-paraffin deposits — paraffin deposits, other clogging formations and removal of the formed passive liquid medium, hydro-pulse the interval processing of the PPP with an active reagent liquid medium and the final removal of the specified passive medium, the solution is injected as the specified active medium erator AFS other bridging structures with replacement fluid jamming while repressionno-exposed depression, the fluid-wise processing is carried out with the addition of muffling hydrophobic surfactants for hydrophilizing the production well or an injection well for surfactants. This problem is also solved by the fact that the proposed method is carried out using a unit for nanowave processing of the bottom-hole formation zone, containing a tubing string, a jet pump installed on it, under which a packer, a pressure multiplier with the possibility of lifting along the well and a depressive pulse generator are placed - DGI, which contains a pressure multiplier with a nanogenerator, described below, and the radial channels of the DGI are at the same level with the lower perforation perforations and wellbore interval. In this case, the pressure multiplier contains a housing connected to the tubing string — a tubing in which a receiving chamber is made, a central channel for hydraulic communication with a depression pulse generator — DGI, and side axial channels for communication with a pressure accumulation chamber formed by the housing and the piston, which can be supported a Belleville spring unit mounted on an abutment, which, with a piston and said block, are seated through the adapter sleeve on the cantilever part of the housing above the adapter pipe connecting the DGI to the housing e and the piston, opposite each other, ring shaped nozzles are fixed, in the counter holes of which are rigidly mounted with the possibility of pairwise contact at the initial position of the piston, cylindrical elements made of piezoceramics.

The feature of the method is:

depressive-repression-impulse action on the capillary system of the formation medium with the phased effect of kill fluids and solutions of chemical reagents in the nanowave field of capillary flows, which leads to the cleaning of capillaries and the formation of microcracks in rocks;

destruction of paraffin and dispersion of solid colmatants in the regime of hydrodynamic and nanowave exposure to solutions of chemical reagents.

Figure 1 shows a complex of technological equipment, which includes a pump unit 1 with a tank of working fluid 2, a string of tubing 3, a packer 4 and, through a set of tubing, a depression pulse generator 5, over which a pressure multiplier with a nanogenerator 6 is located. the annulus in the bottomhole zone can be blocked by the packer 4, to ensure the effective operation of the jet pump or swab.

Figure 2 shows a set of technological equipment with a planted packer 4.

Figure 3 shows a complex of technological equipment with a planted packer 4 and a working swab 7.

Figure 4 shows a set of technological equipment with a working pressure multiplier with a nano-generator and a packer in a transport state.

Figure 5 shows a set of technological equipment with a packer 4 and a working swab 7 for complete removal of the products of the destruction of paraffin and colmatants with their removal to the surface.

Figure 6 shows a General view of the pressure multiplier with a nanogenerator. The device consists of a housing 8, which is connected to a set of tubing 9. In the housing 8 there is a receiving chamber 10, a central channel 11 for hydraulic communication with the DGI (5, Fig. 1) and side axial channels 12 for communication with the accumulation chamber 13.

On the cantilever part of the housing 8, a stop 14 is installed, an adapter pipe 15 for connecting the DGI. A block of disk springs 16 is mounted on the stop 14, which support the piston 17. On the housing 8 on the one hand and the piston 17 on the opposite side are mechanically fastened, for example, ring nozzles — the upper 19 and the lower 20 — are screwed together. The piston 17 and the stop 14 are set on the cantilever part of the housing 8 through the adapter sleeve 21 to ensure the Assembly of the device. Above the screws 18 in the recessing holes of the upper 19 and lower 20 nozzles, cylindrical elements 22 made of piezoceramics, which are generators of nanowaves, are rigidly mounted opposite each other nanogenerators. Elements have the possibility of pairwise contact in the initial position of the piston 17.

The principle of operation of the device is to create a pressure increase during operation in the accumulation chamber 13 by abruptly stopping the flow from the pump unit mounted on the surface, followed by the opening of the annular channel when the spring-loaded piston 17 with the annular nozzle 20 is pressed from the nozzle 19 and the accumulation chamber 13 is opened. The annular nozzles 19 and 20 are profiled in such a way that a cavitational flow of liquid is formed at the exit of the jets from them. When the pressure chamber 13 is opened, the pressure in it drops and under the action of the Belleville springs 16, the piston 17 returns to its original state, while the nozzle 20, returning to its original position, collides with the nozzle 19 through the piezoceramic elements 22. When the piezoelectric elements undergo sharp mechanical loading, a piezoelectric the effect of the appearance of electric charges of a different sign on opposite faces of the elements and, as a consequence, the electrification of a fluid flowing through a nozzle. In this case, the magnetoelastic effect also arises (Villari effect), due to which a magnetic field is created during mechanical deformation of the piezoelectric ceramics and, as a consequence, the magnetization of the liquid [1]. In the first case, the electrification of a liquid with subsequent cavitation sharply increases the effect of cavitation upon hydrodynamic action (lengthening the cavitation torch by 4–5 times), and in the second case, when magnetized, the effect of the target surfactants, surfactants, sharply improves. Once in the pore channels of the collector, cavities of cavitation jets collapse with the formation of high-pressure pulses and, taking into account a large number of caverns, the appearance of a high-frequency vibration spectrum with wavelengths commensurate with the size of the pore channels 10 ^-7 ... 10 ^-9 m, which refers to nanoscale sizes. With the periodic nature of the propagation of nanowaves in the capillaries, adhering particles and colmatants are separated from the walls of the pore channels, followed by their binding by a magnetized liquid and their removal from the pore channels during swabbing.

SUMMARY OF THE INVENTION

During the operation of oil and gas condensate wells, their productivity gradually decreases, and during the operation of injection wells, their injectivity decreases due to deterioration of reservoir properties in the bottomhole zone.

In the proposed method using a nano-pulse generator, the task of increasing productivity and increasing injectivity of wells is solved as follows.

A well is selected for processing and its killing is carried out with aqueous solutions of complex surfactants, aqueous emulsion or oil liquids that do not impair the reservoir properties of the BCP.

Then, a set of technological equipment is lowered into the well (see Fig. 1), which includes a tubing string 3, a packer 4 mounted on it and through a set of tubing-depression pulse generator 5, over which a pressure multiplier with a nanogenerator 6 is installed.

At the first stage, a hydrodynamic effect on the bottom-hole zone is carried out with the kill fluid, gradually replacing it with the target chemical reagents and maximally conducive to the appearance of high-amplitude oscillations in the well. At the same time, the packer is in a transport state, without interfering with the shock loads of the liquid at the BCP, and the fluid is replaced through the annulus, DGI and tubing.

In the second stage, after replacing the kill fluid with the composition of liquid chemical reagents, the packer 4 is planted and the fluid is crushed into the formation through a nanowave generator. In this case, the supply of working fluid to the nanogenerator is carried out from the pump unit 1 through the tubing and pressure multiplier 6, which includes the nanogenerator. Then carry out technological exposure for 12-24 hours for the destruction of paraffin and dispersion of solid colmatants.

At the third stage, with the help of a swab and DGI, they carry out the removal of contaminated particles and products of the destruction of paraffin deposits to the surface.

At the fourth stage, the packer is transferred to the transport state and the PZP is processed periodically by a pressure multiplier with a nanogenerator using a kill fluid with the addition of a hydrophobizing surfactant for the production well or a hydrophilizing surfactant for the injection well.

At the fifth stage, the well is packaged and, with the influence of DGI, create multiple depressions in the bottom-hole zone using a swab. The operation is repeated until the complete destruction of the paraffin and solid colmatants from the BCP.

As reagents, hydrocarbon solvents Nefras A-150/200, Nefras AK, a mixture of aromatic and aliphatic solvents FLEK and others are used, adding surfactants - Penta 491M, Synterol, diproxamine 157-65M, Reopon IR and others in an amount of 0.01-0 , 1 wt.%. Complex surfactants, including Neftenol K, Sofexol MFK, Sinol KAM and others in a concentration of 0.3-4.0 wt.%, Are added to water-based suppression fluids. The same surfactants in the indicated concentrations can be used in acid treatments of producing and injection wells using acid pulse multipliers. For hydrophobization of the pore space of the PZP, cationic oil-soluble surfactants - Don 52, Don-96, Penta-804 and others in a concentration of 0.1-1.0 wt.% Or water-soluble surfactants - Neftenol K, Neftenol GF, IVV-1, Catamine AB are used and others in a concentration of 0.5-1.5 wt.%. For hydrophilization of the pore space of the PPP, solutions of anionic surfactants are used - Neftenol NS, Sulfanol, Oksifos B and others in a concentration of 0.3-2.0 wt.%. Anhydrous oil from oil treatment plants, mineral formation water, and aqueous solutions of salts are used as a suppression fluid. Surfactants — Penta 491-M, TH 10, SNPCH 4480, and others — are added to the oil killing fluid at a concentration of 0.01-0.1 wt%.

An example of a specific implementation.

The bottom-hole zone of a producing well with a depth of 1860 m, which uncovered a productive formation 5.5 m thick at the Sovetskoye field of the Tomskneft Oil and Gas Production Unit, is processed.

Killing the wells with light anhydrous oil with the addition of 0.05 wt.% Demulsifier - Penta 491-M.

The nano-generator is tuned to a predetermined response pressure of the mechanism for instantly opening the accumulator chamber of the pressure multiplier.

A set of technological equipment, consisting of a packer, a pressure multiplier with a nanogenerator and DGI, is lowered into the well on the tubing and placed in such a way that the radial channels of the DGI are at the same level as the lower perforations of the borehole perforation interval.

Using a swab installation, fluid is removed from the tubing, creating a pressure drop between the tubing and the annulus, at which the DGI valve instantly opens, and fluid from the annulus rushes into the tubing, creating a sharp decrease in pressure in the annulus. A deep impulse of depression occurs at the bottom of the well, causing accelerated fluid movement in the near-wellbore zone. After filling the implosion chamber with liquid, the hydrostatic pressure of the liquid column in the annulus creates a repression pressure impulse, which propagates in the bottomhole zone of the well.

The creation of multiple and alternating in time pulses of depression and pressure pulses leads to the destruction of stable emulsions, loosening of paraffin deposits and the formation of microcracks in the rocks of the bottomhole formation zone.

At the same time as pumping out the kill fluid through the tubing, a composition of liquid chemicals is added to the annulus of the well to dissolve and remove ASPO-Nefras-150/200 with the addition of 0.05 wt.% Demulsifier-Penta-491M.

Pulse swabbing using DGI is stopped after replacing the kill fluid with the specified composition and entering it into the bottomhole zone and tubing.

At the next stage, the packer is planted and the AFS solvent is crushed into the formation through a pressure multiplier with a nanowave generator.

After technological exposure for 12 h, using the swabbing unit and DGI, the products of the destruction of paraffin deposits and colmatants are removed from the BCP. At the next stage, the packer is transferred to the transport state and the reservoir is periodically treated for the producing well every 20 cm with a kill fluid - anhydrous oil with a hydrophobizing additive of 0.5 wt.% Don-52.

After hydrophobization of the bottom hole, technical equipment is removed from the well, pumping equipment is lowered onto the tubing and the well is put into operation.

Before the nanowave treatment of the bottom-hole zone, the production rate of the well was 1.5 tons / day, and after processing it became 6 tons per day for oil.

The application of the proposed method, installation, multiplier for processing the bottomhole formation zone of producing oil, gas condensate and injection wells will allow increasing the productivity of the wells at minimal cost.

Claims (3)

1. A pressure multiplier with a nanogenerator, comprising a housing connected to a tubing string, in which a receiving chamber is made, a central channel for hydraulic communication with a depression pulse generator — DGI and lateral axial channels for communication with a pressure accumulation chamber formed by the housing and the piston, a lockable cup spring unit mounted on an abutment which, with a piston and said unit, are seated through the adapter sleeve on the cantilever part of the housing above the adapter pipe for connecting the DGI, annular shaped nozzles are fixed on the body and piston opposite to each other, in the counter holes of which are rigidly paired with the initial position of the piston cylindrical elements made of piezoceramics. 2. Installation for nanowave treatment of the bottom-hole formation zone, comprising a tubing string, a jet pump mounted on it, under which a packer is sequentially placed, a pressure multiplier according to claim 1 with the possibility of lifting along the well and a depression pulse generator — DGI, whose radial channels are at the same level with the lower perforations of the hole perforation interval. 3. The method of processing the bottom-hole zone of the formation — the bottom hole using the installation according to claim 2, which includes injecting the active reagent liquid medium into the bottom hole zone and then into the bed, exposure to break the asphalt-resin-paraffin deposits — paraffin deposits, other clogging formations and removing the resulting passive liquid medium hydroimpulse interval processing of the PPP with an active reagent liquid medium and the final removal of the specified passive medium, and the solution is injected as the specified active medium voritelya AFS other bridging structures with replacement fluid jamming while repressionno-exposed depression, the fluid-wise processing is carried out with the addition of muffling hydrophobic surface - active agent - surfactants for hydrophilizing the production well or an injection well for surfactants.

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