-
This invention relates to operating oil and gas wells, wells in aquifers and other types of wells and is used for treating the areas of the stratum adjacent to the drilling area of the well for the purpose of increasing permeability of the bedrock and therefore productivity.
OBJECT OF THE INVENTION
-
A pressure pulse generator, by means of gas injection, which is introduced in the drilling area of the well, being located in the areas of the oil and gas well having maximum saturation and maximum flow intensity, to which areas high energy impact pulses are transmitted with a certain duration of the impact wave vibrations until they are completely dampened, and low energy pressure impact pulses are subsequently generated.
STATE OF THE ART
-
The extraction of oil reservoirs from fossil fuel deposits is initially carried out by means of drilling wells in certain places of the deposit and the oil and gas come to the surface usually due to the effect of natural pressure. The natural thrust may be due to:
-
- i) dissolved gas, in this case the recovery of the reservoirs can reach up to 20%,
- ii) layer of gas on the deposit, in this case the recovery of the reservoirs can reach up to 40%;
- iii) layer of water under the deposit, in this case the recovery of the reservoirs can reach up to 50%).
-
In any case, and in general, the total natural pressure factor existing in the deposit does not enable recovering more than 30-35% of the oil reservoirs provided that the viscosity thereof is less than 10%.
-
When natural pressure decreases and the production of the well therefore decreases, artificial methods are used to put pressure in the deposit (injecting water or injecting gas in specific places)
-
The oil is usually trapped in the conduits of what is referred to as bedrock (similar to a large sponge with microscopic channels) and as the oil is being extracted, the network of channels in the bedrock which are adjacent to the walls of the well become backfilled (blocked), decreasing the production capacity of the well.
-
When the conduits in the bedrock layer adjacent to the walls of the well become backfilled, artificial methods are used to recover the flow of oil to the well.
-
The problem of using new methods for intensifying the flow of oil and gas in already drilled, active or marginal wells is very important worldwide essentially due to the decrease of the amount of new drilling (new wells), the lack of drilling equipment, the substantial increase in the cost of drilling jobs and the decreased amount of new deposits.
-
All state-owned and private companies are searching for technical solutions to be able to increase their current production capacity by means of incorporating new deposits and their corresponding drilling and by means of increasing the production of current active and marginal or abandoned wells with the use of technologies improving production.
-
Inactive wells can essentially be defined as:
-
- a) Wells that had low production when first operated
- b) Wells experiencing a sudden drop in productivity
- c) Wells with technical difficulties in extraction (there are several reasons, such as a high amount of water, high gas to oil ratio, etc.)
-
There are several technologies that can improve the production of low-productivity wells and inactive wells.
-
The most widely used technology-methodology today to increase production is hydraulic fracturing of the backfilled area of the bedrock (HF). This technology uses pressurized water to break the backfilled areas and to recover the flow of oil or gas to the well. HF is the technology mostly used by large specialist firms in the field, and requires high financial investments and a long implementation time period (between 20 and 30 days), its effect lasting a maximum of approximately 2 years. HF technology has limitations for use in deposits in which water is injected during the treatment of the strata containing oil or gas with their borders close to the strata containing gas-water or oil-water. Fracturing the bedrock in the HF process is furthermore unpredictable essentially due to the fact that the most suitable amount and pressure of the water for unblocking the backfilled areas can not be exactly determined, possibly irreparably damaging the wells and not always reaching the desired increased oil production.
-
The use of hydraulic fracturing is not always justified because in most cases it is enough to simply unblock the area of the strata of the wells and recover its filtration qualities in order to recover the stratum-well hydrodynamic connection (flow of oil or gas from the bedrock to the well).
-
Other technologies known for reanimating oil and gas well production are based on injecting gases and chemical products in the backfilled areas include:
-
- 1.—Fracturing the backfilled areas of the bedrock by means of injecting gases coming from a powder explosion through (initially sealed) nozzles of a container (which is introduced in the well).
- The backfilled area of the stratum adjacent to the drilling area of the well is treated by means of introducing a container in the well, which contains a section where gas accumulates at a high pressure, the one-way start valve, a section of the container where gas accumulates at a low pressure, the gas supply system, the control system and at least one nozzle for injecting gas in the backfilled area.
- The powder charge ignites for example with a pyrotechnic cartridge by means of the supply of the electric pulse from an external power source. The nozzles are sealed in the initial position of the generator.
- The drawbacks of this method are the complexity of setting the impact parameters (amount and pressure of gases to be injected) during treatment, the need to use explosive substances, the considerable temperature increase occurring during combustion of the powder charge and, as a result, the possible agglomeration of the backfill agent in the area of the bedrock adjacent to the drilling of the well, the absence of the gas pressure energy impact selectivity, the volume of gas to be injected. With this method it is very complicated to open all the nozzles strictly simultaneously. Usually part of the nozzles opens, the pressure of the powder gases in the cavity of the generator body drastically decreases and another part of the nozzles can remain sealed. The result is that only one part of the area adjacent to the drilling area of the stratum of the well is subjected to treatment, decreasing effectiveness of operating the generator, and then the well productivity increase is low.
- This technology has a main drawback due to the fact that it is based on an approximate calculation of the location of the area to be unblocked; it involves expenses that exceed the working agents; it destroys the node of the valves of the dampening element during application; and a low well productivity increase is obtained after treatment.
- 2.—A method is known for treating the backfilled area of the stratum adjacent to the drilling area of the well which is based on the fact that the increased well output occurs as a result of substances diluting the backfill and mechanical impurities that fill up the porous space in the rock of the fuel reservoir producing stratum; this dilution is achieved by means of a chemical reagent that is poured from the surface to the area of the stratum to be unblocked; the most widely used substances are hydrochloric acid, the mixture of hydrochloric acid with hydrofluoric acid or with ammonium fluoride and hydrofluoric acid (NH4*HF+NH4F).
- The drawback of the method indicated above is the low effectivity of the chemical reagent impact due to its negligible penetration into the backfilled stratum and due to the relative immobility of the reaction products in the treatment area.
- 3.—A method is known for treating the area adjacent to the area of the stratum of the well to be unblocked, by means of the surfactant substances contributing to the dilution of the residue of the argillaceous solution and of other backfilling products of the bedrock. The effectiveness of this method is also limited by the insignificant depth of the penetration of the surfactant substances to the deeper backfilled porous areas with a low permeability.
- 4.—The method of treatment with pressure pulses due to the injection of gases is known. In this technology the gas accumulator is loaded at the surface with the gas (e.g. nitrogen) under high pressure before submerging it in the well, and the high pressure gas exhausts occur with the pulse energy from 10 to 200 kJ. The frequency and duration of the high pressure gas exhaust pulses are controlled from the surface, the frequency and the duration of the pulses are further chosen according to the characteristics that are identical or similar to resonance characteristics of the productive stratum. The gas accumulator-dispenser moves up and down, releasing the gas throughout the area of the productive stratum.
- However, this method is not sufficiently effective because it is lacking the selectivity characteristic of the pressure pulses taking into account the heterogeneity of the area to be treated regarding the bedrock oil and gas saturation and the flow intensity and other properties of the stratum containing oil and gas. Furthermore, the order of treatment procedures is not determined according to the energy and frequency parameters depending on the mentioned factors of heterogeneity of the backfilled area.
- Furthermore, the order of the treatment of the strips of the backfilled areas is not determined, taking into account their location in the well and the distribution of the impact waves. It does not take into account the additional energy possibilities of the impact that may occur in the area adjacent to the backfilled areas, which show up during the process of the oscillation of the hydrostatic level of the liquid when injecting the gas into the well.
- 5.—Another known method is the combined treatment by means of exploding an explosive substance charge in a reagent solution deposited in the backfilled area, keeping the well sealed.
- The result of the explosion is the destruction and dispersion of the sediments of the backfilled bedrock under the action of the blast wave by means of introducing the reagent solution, under pressure, at a significant depth of the bedrock as a result of the pressure in the gas and vapor expansion process, the value of which is 5-10 mPa.
- However, this method is insufficiently effective due to the use of explosive substances, with a high risk of starting fires, the complex handling of the impact parameters and the high temperatures involved in the explosive substance combustion process, which negatively affects the reaction rate and the conditions of the treatment area, with a high backfill agglomeration possibility. This method can only be used in shallow wells because the gas pressure of 5-10 mPa is not enough to clean and create additional cracks in bedrock in wells that are over 200 meters deep. The effectiveness of the method is furthermore limited by the single (i.e. not multiple) impact with gradual dampening of the impact energy through the pores of the bedrock.
- 6.—The known method that is most similar to our invention is the method of treating the backfilled strata of the well by means of an energy pulse container-generator. The method consists of introducing the pressure pulse generator into the well and the subsequent treatment with pulses at an interval in the backfilled area consecutively on the areas to be unblocked by means of stopping the generators in front of such areas.
- The drawbacks of this method are the low energy capacity of the pulse on the bedrock and, additionally, selecting the location of the generator according to the wavelength and not according to the degree of gas and oil saturation in the backfilled area.
- 7.—Other well recovery-reanimation methods can be used in the secondary and tertiary recovery steps such as thermal impact, gas and chemical injection, electric pulse, acoustic pulse, chemical pulse, expansive clay methods, etc. (there are more than 100 different production improvement technologies-methodologies). All the mentioned methods provide reasons for their reasonable use but at the same time they have many drawbacks, mainly including the following:
- a) the absence of precise selection of the backfilled area of the well taking into account the lack of homogeneity regarding the oil content and the bedrock qualities
- b) the low level of energy in the known methods for injecting gases into the bedrock, which does not assure an increased permeability in the backfilled area of the well;
- c) the absence of devices affording the possibility of changing the injection process and parameters and adapting the parameters of the impact according to the geological conditions of the rock, the condition of the well, of the deposit . . .
- d) they are environmentally hazardous [HF involves separating the water (used for fracturing) from the oil at the output of the well and said water is contaminated with a percentage of hydrocarbons and their substances; the addition of (highly pollutant) chemical components to the oil subsequently flowing to the mouth of the well, etc]
- e) they are restricted for use in deposits in which the borders of the oil and gas producing strata are very close to the borders of the water and gas strata of said deposits.
- f) over time (between a year and a half and two years) permeability of the stratum and its filtration properties decrease, the drilling area becomes backfilled and the oil production effectiveness decreases.
DESCRIPTION OF THE INVENTION
-
The invention relates to a device according to claim 1 and to a method according to claim 4. Preferred embodiments of the invention are defined in the corresponding dependent claims.
DESCRIPTION OF THE DRAWINGS
-
To complement the description and for the purpose of aiding to better understand the features of the invention according to preferred practical embodiments thereof, a set of drawings is attached as an integral part of said description, showing the following in an illustrative and non-limiting manner:
-
FIG. 1 schematically shows a container—dispenser (version with the intermediate section located between the high pressure section and the low pressure section) according to a preferred embodiment of the invention.
-
FIG. 2 schematically shows different elements associated with the invention according to a possible embodiment thereof.
DETAILED DESCRIPTION OF THE INVENTION
-
The result of the invention is the creation of a technological equipment and a methodology having a completely ecological application for treating the backfilled area adjacent to the drilling area of the stratum of the well, providing high effectiveness and selectivity of the impact for cleaning and fracturing the backfilled area of the stratum taking into account the heterogeneity of the area of the rock to be treated regarding gas and oil saturation, obtaining a considerable production increase.
-
The technological equipment of this invention consists of a cylindrical container, dispenser of high energy pulses based on injecting gases, containing three sections and different auxiliary equipment:
-
- The body of the generator has three parts: high pressure section, low pressure section and intermediate area, which is located between the high pressure section and the low pressure section, or else in the lowest part of the high pressure section.
- The element used as the gaseous medium (nitrogen) is stored in the high pressure section.
- The intermediate section has nozzles for transporting the gas to the backfilled area; in the low or high part (according to the arrangement thereof) of the intermediate section there is a conical hole for the entrance of the front section of the one-way start valve; the valve is made in the shape of a vessel; the front section of the valve is at the bottom of the vessel in which a spring is installed, fixed to the upper base of the intermediate section.
- Due to the design of this invention, with the inclusion of the high pressure one-way valve in the construction, high pressure gaseous nitrogen necessary for the treatment effectiveness can be accumulated in the high pressure section. The nitrogen can be previously introduced in the high pressure section of the container before being submerged in the well (nitrogen purchased on the market or produced at the application site by means of equipment for producing nitrogen from the air—nitrogen-oxygen separation) or produced inside the high pressure section by means of a chemical reaction.
- In the event that the nitrogen is not commercially available at the work site, an acid mixture of an alkali metal with a metal oxide, for example the acid mixture of sodium with iron oxide, can be used as a means of producing nitrogen inside the high pressure section. The chemical combustion reaction of the mixture occurs by means of igniting the mixture (for example by means of the pyrotechnic cartridge and the igniter), which is commanded from the switching block.
- The combustion reaction of the mixture can generally be described with the equation:
-
2MN3+RxO═MO+XR+3N2
-
- where M is an alkali metal, R is a metal, X is the valence.
- As a result of the combustion reaction of the mixture, gaseous nitrogen is produced, accumulating in the high pressure section of the generator, and when the nitrogen temperature reaches 550-700° C. and the nitrogen pressure reaches 30.0-180.0 MPa, the gaseous nitrogen is injected through the nozzles located in the intermediate area into the area to be treated. Due to the special design and technical features and radial arrangement of the nozzles, the nitrogen is injected into the backfilled area on the entire surface next to the borehole of the well and in a time period that does not exceed one second.
- Installed in the low pressure section are the gamma radiation detection apparatus and the material hardness-solidity locator, along with the recorder of the precise location of the generator inside the well, located on the surface, by means of a geophysical technological logging cable.
- The data analysis block to analyze the data acquired by the gamma radiation equipment and the material hardness detecting equipment, transmitted through a technological cable located on the surface.
- The generator operation control block (regulation of the one-way valve opening parameters, nitrogen pressure and temperature parameters, etc).
-
FIG. 1 schematically shows the container—dispenser (version with the intermediate section located between the high pressure section and the low pressure section), in which:
-
- 1. High pressure section
- 2. One-way valve
- 3. Nozzles for injecting gas
- 4. Intermediate section
- 5. Gamma radiation detection apparatus
- 6. Material defects (inseparability) locator
- 7. Generator location recorder
- 8. Comparison block
- 9. Generator control block and control circuit
- There is a variant in which radially-arranged nozzles for injecting nitrogen into the backfilled area are located in the lower part of the high pressure section.
-
The methodology for applying this invention in treating backfilled productive areas of the stratum of the well is as follows:
-
The method is carried out by introducing the pressure pulse generator (container) in the well and the subsequent treatment of the area to be treated, in which the values of gas and oil saturation and of the flow intensity are maximum, by generating pressure pulses at intervals in the area to be treated in a consecutive manner by means of stopping the generator in front of such areas. First, pulses are generated with an energy of 250-400 kJ (impact pulse energy with values of less than 250 kJ is not enough to destroy the solid rock skeleton and to create the network of additional microscopic cracks which increase permeability of the drilling area; the energy of impact pulses with values exceeding 400 kJ can damage the casing in the drilling area), the vibrations of the impact wave lasting until they are completely dampened through the channels in the bedrock. Then the pulses are generated with an energy of 6-8 kJ and a frequency of 10-15 Hz, thus contributing to the most effective purification of the backfilled deposits and the mechanical impurities of the natural porous space of the rock and of the network of microscopic cracks therein. Pulse treatment is carried out when the mouth of the well is sealed. Treatment is conducted from bottom to top, starting from the deepest backfilled area of the well. After the pulse treatment has ended and before removing the container-generator from the well to the surface, release pressure is created in the drilling area.
-
The method for applying the invention allows significantly increasing the effectiveness thereof and the selectivity of the impact, for example applying it to treat oil wells allowed a 3-7 fold increase in production and the effect lasted for a period of over 2 years.
-
The process for applying this invention is as follows:
-
- 1. The container is introduced in the well and geophysical investigations are performed (by means of a gamma radiation detector and a rock hardness detector) for the purpose of selecting the areas of the productive stratum of the well with maximum gas and oil saturation and with maximum flow intensity.
- 2. The container-pulse generator stops in the first located area of the well having maximum saturation located in the lowest part of the well.
- After the generator stops in the designated area, a command is sent from the surface to start up the generator-gas injection and to open the high pressure one-way start valve, which allows supplying nitrogen to all the nozzles of the intermediate section simultaneously, resulting in identical treatment conditions for the entire drilling area of the stratum. The generated impact pulses have an energy between 250-400 kJ, the vibrations of the impact waves lasting until they are completely dampened. The result of the action of the waves is the destruction of the skeleton of the backfilled rock and the creation of a network of additional microscopic cracks which in turn increase the permeability of the area adjacent to the area of the stratum next to the drilling area. Subsequently in the same area the pulses are generated with an energy of 6-8 kJ and with a frequency of 10-15 Hz, contributing to the purification of the porous space and to the increased mobility of oil and gas in the porous space.
- 3. The parts that are located with maximum oil and gas saturation and with maximum flow intensity in the drilling area of the well are treated successively, one after the other, from bottom to top.
- 4. In order to use the additional energetic possibilities of the impact of the oscillations of the hydrostatic level of the liquid on the area to be treated during pulse treatment, said treatment is conducted with the mouth of the well being sealed, whereby complete purification of the mechanical impurities of the area adjacent to the drilling area of the well is obtained and therefore the flow is intensified in the treatment area.
- The method and technological equipment of this invention for injecting gas with a large amount of energy in well areas directly related to oil extraction has a number of advantages and differences in comparison with other intensification methods, such as:
- 1. It requires a period of 2 days and its cost is much lower than the cost of treatment with other known technologies and methodologies.
- 2. It is the only method for increasing oil production that is environmentally friendly and does not involve the risk of fire because a neutral gas (nitrogen) is used as the working element to exert an effect on the stratum.
- 3. It maintains the obtained production increase for a period of 2 to 5 years without a considerable oil production decrease.
- 4. It allows very precisely selecting the impact on the area of the stratum of the borehole taking into account its non-homogeneity in terms of the degree of oil saturation and taking into account the properties of the rock (impact in local areas which are the areas most saturated with oil in the well).
- 5. It can exactly determine the stratum saturated with oil and gas and the intensive impact on it by means of nitrogen flows contributes to increasing the fluidity of the oil and to the increased productivity of the well.
- 6. It obtains a high level energy impact concentrated along 1.0-1.5 meters of the backfilled areas of the stratum containing the reservoirs, assuring the increased permeability.
- 7. It provides the possibility of regulating the impact processes and adapting the impact parameters according to the geological and rock conditions, the condition of the well, of the deposit and other factors (the most effective impact parameters are defined according to the amplitude, frequency and duration of the pulse).
- 8. It allows considerably increasing the volume of oil extracted from the wells in low productivity or closed deposits as a result of the purification and recovery of the filtration properties in the area of the productive stratum next to the drilling area.
- 9. It can be used as a preventive measure for the increased productivity of active wells as well as to increase the productivity of injection wells.
- 10. It can be applied at the same time that the submersible pumps and equipment of wells are replaced in accordance with regulations (maintenance).
- 11. The submersible generator of this type of construction can be used repeatedly.
-
The tests conducted with the technology of the invention achieved the following results:
-
| |
| |
|
|
|
Oil |
Oil |
|
| |
|
|
|
Productivity |
Productivity |
Production |
| |
|
|
Operating |
before GIE |
after GIE |
increase |
| Deposit |
Well No. |
Conditions |
Method |
bbl/day |
bbl/day |
bbl/day |
| |
| |
| Tarasovskoe |
443/109 |
Operating |
Jet |
30.6 |
69 |
38.4 |
| Tarasovskoe |
713/179 |
Operating |
Jet |
13.2 |
72 |
58.8 |
| Tarasovskoe |
671/101 |
Operating |
Jet |
4.8 |
211.2 |
206.4 |
| Samotlorskoe |
50672/ |
Operating |
Centrifugal |
57.6 |
279.6 |
222 |
| |
2146 |
|
pump |
| Samotlorskoe |
8877/322 |
Operating |
Rod pump |
45.6 |
81.6 |
36 |
| Lor-Eganskoe |
04/555 |
Operating |
Centrifugal |
42 |
96 |
54 |
| |
|
|
pump |
| Bajilovskoe |
1067/6 |
Inactive |
— |
0 |
90 |
90 |
| Beresovskoe |
7080 |
Operating |
Rod pump |
7.8 |
16.8 |
9 |
| Beresovskoe |
7023 |
Operating |
Rod pump |
3 |
15 |
12 |
| Ersubaikinskoe |
11076 |
Inactive |
Rod pump |
2.4 |
13.8 |
11.4 |
| Ersubaikinskoe |
4895 |
Inactive |
Rod pump |
2.4 |
16.2 |
13.8 |
| Vostochno- |
836 |
Operating |
Centrifugal |
48 |
157.2 |
109.2 |
| Vajskoe |
|
|
pump |
| Vostochno- |
822 |
Operating |
Rod pump |
24 |
51 |
27 |
| Vajskoe |
| Samotlorskoe |
443 |
|
Rod pump |
25.2 |
66.6 |
41.4 |
| Samotlorskoe |
713 |
|
Rod pump |
13.2 |
81 |
67.8 |
| Samotlorskoe |
671 |
|
Rod pump |
48 |
228 |
180 |
| Tarasovskoe |
671 |
|
Rod pump |
42 |
222 |
180 |
| Tarasovskoe |
713 |
|
Rod pump |
13.2 |
82.8 |
69.6 |
| Tarasovskoe |
443 |
|
Rod pump |
30 |
66 |
36 |
| Ersubaikinskoe |
4895 |
|
Rod pump |
4.2 |
18.6 |
14.4 |
| Ersubaikinskoe |
11076 |
|
Rod pump |
4.2 |
14.4 |
10.2 |
| Bajilovskoe |
1076 |
|
Rod pump |
28.2 |
90 |
61.8 |
| Beresovskoe |
7023 |
|
Rod pump |
4.8 |
13.8 |
9 |
| Beloserneft |
18010 |
|
Rod pump |
0 |
18 |
18 |
| |
group |
| |
845 |
| Beloserneft |
13726 |
|
Rod pump |
105 |
216 |
111 |
| |
group |
| |
1054 |
| Beloserneft |
40241 |
|
Rod pump |
27 |
102 |
75 |
| |
group |
| |
1789 |
| Beloserneft |
3934 |
|
Rod pump |
84 |
174 |
90 |
| |
group |
| |
250 |
| Beloserneft |
40040 |
|
Rod pump |
0 |
126 |
126 |
| |
group |
| |
1733 |
| Slavneft meghion |
5295 |
|
Rod pump |
24 |
78 |
54 |
| neftegas |
group |
| |
212 |
| “Tursunt” c. Uray |
4237 |
|
Rod pump |
0 |
42 |
42 |
| deposit |
| Slavinskoe |
| “Tursunt” c. Uray |
10344P |
|
Rod pump |
5.4 |
15 |
9.6 |
| deposit |
| Slavinskoe |
| “Mojtik” |
298 |
|
Rod pump |
60 |
93 |
33 |
| Rasvedochnaya |
| “Mojtik” |
119 |
|
Rod pump |
24 |
60 |
36 |
| Rasvedochnaya |
| “Mojtik” |
296 |
|
Rod pump |
60 |
564 |
504 |
| Rasvedochnaya |
| “Meghion” |
3521/220 |
|
Rod pump |
24 |
108 |
84 |
| Vatinskoe |
| “Yurganeft” Malo- |
255/5A |
|
Rod pump |
12 |
48 |
36 |
| Chernogorskoe |
| “Aganneftetejnologia” |
18-sea |
|
Rod pump |
24 |
60 |
36 |
| Mogutlorskoe |
| Bystrinskoe c. |
3156/180 |
|
Rod pump |
15 |
48 |
33 |
| Surgut |
| Komsomolskoe |
2595/206 |
|
Rod pump |
9 |
18 |
9 |
| Komsomolskoe |
2565/206 |
|
Rod pump |
9 |
18 |
9 |
| TOTAL |
|
|
|
928 |
3,841 |
2,912 |
| |
-
The scopes of the reasonable use of this invention are:
-
- Wells having a productivity that is abruptly reduced in reference to the adjacent wells working in the same stratum;
- Wells having a productivity that is abruptly reduced in the operating process with the pressure of the deposit being preserved;
- Wells with an argillaceous drilling area;
- Wells in the deposits having hard-to-extract reservoirs due to the low permeability and low porosity of the rock;
- Wells that are inactive for a long period of time, including wells that have been fully repaired, including underground repair;
- Injection wells with low susceptibility;
- Wells prepared for hydraulic fracturing;
- Wells in which productivity has dropped over time after implementing hydraulic fracturing;
- Wells that do not react to other production intensification methods.
- Pumping wells with a low production
- Wells which do not accept other intensification methods
-
Basic features of the wells in which the invention provides the best output include:
-
- They at least allow oil extraction by pumping
- The pressure between layers is not less than 70% of the hydrostatic pressure
- The reduction in production that the well has experienced is mainly due to backfilling of the filter and the holes of the bedrock
- Vertical or inclined wells
-
The equipment for applying the invention comprises:
-
- a group of submersible containers in the pipe of the well with a diameter of 5 or 6 inches (105 to 120 mm)
- elevator of the containers for storing and transporting them to the wells.
- the pneumatic-hydraulic system and pressure multiplier for supplying the necessary pressure to the gas containers-dispensers before submerging them in the wells (in the event of using commercial liquid nitrogen)
- the gaseous nitrogen production-regasification system (in the event of using commercial liquid nitrogen)
- a technological assembly for producing-separating nitrogen from the air in the event that commercial nitrogen is not available.
- the operating control and management block of the containers-dispensers
- All the equipment is mobile; it is assembled in trucks and has connecting points for being able to work with common equipment in standard drilling equipment.
-
FIG. 2 shows the following elements:
-
11. well; 12. Device for probing on the platform; 13. Device for probing inside the well; 14. Device for probing the reservoir with a cover; 15. pneumatic loader; 16. trailer; 17. KRS elevator; 18. logging elevator; 19. geophysical cable; 20. casing; 21. driving guide; 22. crosshead; 23. mouth nipple; 24. cover of the probing device; 25. drilling area; 26. auxiliary hoist cable
-
All the requirements relating to occupational hazard prevention for the petrochemical industry were strictly complied with in the process of designing and manufacturing the equipment of the invention.