Method of oil field development

FIELD: oil and gas industry.

SUBSTANCE: under this method the field is drilled according to row system with triangle grid of wells. Work agent is injected in the injection wells. Oil production is performed from production wells. At initial stage of the field development the production reservoir is presented by two horizons, if divided by central separating row of injecting wells with spacing between wells at least 300 m. Central separating row is arranged along line of maximum pay structure, the injection wells in it are made with opening by common filter of the both horizons. The closest first row of the production wells is drilled at distanced from the central row at least 500 m. Other areas of the reservoir are drilled with spacing between wells 300-400 m. After injection of the central row of the injection wells to 0.4-0.7 unit fractions of the pore volume to nearest rows of the production wells at least 90% wells of the central row are shutdown. After oil withdrawal at the entire field to 90% of initial oil productive capacity between the central separating row of the injection wells and nearest row of the production wells the sealing row of the production wells is drilled. Wells of the central row are switched to production at top horizon. During watering of the production wells of the first row to 98% they are switched to water injection.

EFFECT: increased oil recovery factor of the field.

2 ex, 2 dwg

 

The invention relates to oil industry and may find application in the development of oil fields, reservoirs of which is represented by terrigenous reservoir and consist of two horizons.

A method of developing oil fields, including in-line placement of injection wells, the placement of production wells between the rows of injection wells with a given grid spacing of drilling and compaction by drilling additional wells, the pumping displacement of the working agent through injection wells and oil extraction through production wells. According to the invention the seal grid drilling of wells is carried out at the initial stage of development through the placement of additional wells around each producing well in the grid drilling to form a single structural element due to the location of faces additional producing wells within the bottom zone (rPReach producing well, which is calculated by the formula: rPR=rcexp(-S), where rc- the actual radius of the well, S is the coefficient of perfection wells (the patent RF 2167276, CL. EV 43/20, publ. 20.05.2001).

The disadvantages of this method are uneven depletion of reserves of oil, low rate of extraction of oil, fast obvodnennost �obitaemoj products and as a result, low oil recovery factor (ORF).

The closest in technical essence to the proposed method is a method of oil field development, including in-line drilling of vertical injection and production wells, injection of the displacing working agent through injection wells and oil extraction through production wells. According to the invention in the first stage, pairs of wells drilled injection of rows and next to them the first series production wells and putting them into operation, in the second stage doubles drilled and put into operation in the second series of wells closest to the first rows of production wells, and drilled and put into operation tightening the Central row of producing wells, and by injection at the first stage master injection wells in the series in one, then in the second stage, after working on oil mastered by injection of the remaining injection wells series and all producing wells of the first extractive ranks and through one of the second extractive rows subjected to hydraulic fracturing (fracking) and at the last stage by injection master production wells, forming transverse rows, after their testing for oil, and production wells tightening of the Central range of the Buryats in the form of horizon�the intelligent and/or multilateral horizontal wells with decrease number of wells project this number 3 times (patent RF №2476667, CL. EV 43/20, publ. 23.06.2011 - prototype).

The known method allows to achieve greater KIN to a relatively flat surface deposits at the field. In practice, almost always occur deposits, deposits which have higher and lower patterns. For such fields the efficiency of waterflooding, uniform generation and, therefore, oil recovery remain low.

In the proposed invention solves the problem of increasing oil recovery oil fields.

The task is solved in that in the method of developing oil fields, including drilling of the Deposit layer system with a triangular grid of wells, extraction of oil from production wells, injection working agent in injection wells, transfer of wells into injection and Vice versa, according to the invention at the initial stage of development of the field, the reservoir of which is represented by two horizons, shared between the Central cutting near injection wells with well spacing of less than 300 m, with the Central cutting up some place along the line of the maximum of the structure of the reservoir, injection wells which perform the autopsy General filter both horizons, the closest (first) series of wells are drilled at a distance from the Central range of not less than 500 m, �asburiae other areas of the reservoir is carried out with a distance between holes of 300-400 m, after pumping near Central injection wells 0,4-0,7 proportion of units of the pore volume to the nearest rows of wells stop not less than 90% of the wells in the Central row of injection wells, after the extraction of oil in the whole of the Deposit is more than 90% of the initial recoverable reserves of oil between the Central cutting near the injection wells and the nearest adjacent extractive sealing drilled a series of wells, and the wells of the Central row are transferred to an extraction in the upper horizon in flooding of wells of the first row to 98% of their transfer to water injection.

Summary of the invention

The oil recovery, oil field reservoirs which is represented by terrigenous reservoir, is substantially influenced by the development system and its change in time depending on the stage of development, location of production and injection wells taking into account the Geology of the formations, the volumes of pumped water, etc. Existing technical solutions do not fully allow us to take away the oil from these fields and to achieve high values of CIN. In the proposed invention solves the problem of increasing oil recovery oil fields through optimization of the development system in time. The problem is solved as follows.

Fig. 1 is a schematic view of an oil field in the plan with the placement of wells. Fig. 2 is a schematic view of a section along the line a-A oil field with the placement of wells. Notations: 1 - the fallow field, 2 - Central cut through a number of injection wells, 3 - nearest (first) rows of production wells, 4 - sealing the ranks of the producing wells, S is the distance between the wells in the Central cut through row 2 of the injection wells, the X - distance from center of row 2 to the first number 3 producing wells, the Z - distance between holes the rest of the reservoir 1 (hereinafter, a first series of wells when driving to the arched sections of the Deposit), BHK - oil-water contact In the upper oil horizon, N - lower oil-bearing horizon.

The method is implemented as follows.

Oil field presents one big reservoir 1 (Fig. 1). Reservoirs are combined into two horizons (upper and lower In N) with terrigenous reservoir (Fig. 2). The reservoir 1 has an anticlinal structure. The Central part of the deposits along the major axis, is the dome.

Along the major axis of the deposits drilled Central cut Bank 2 injection wells with well spacing of not less than S=300 m. Open General filter both �of Orizont In and N. The closest number 3 producing wells are drilled at a distance from a center of a number not less than X=500 m. Reveal a common filter or both, one or the horizon. The rest of deposits 1 razvarivat also be layer system with a triangular net production and injection wells with well spacing Z=300-400 m.

According to research in the development of oil deposits anticlinal shape (Fig. 2) with the distance X of about 500 m between the Central injection next 2 next 3 and the first producing wells at the initial stage of flooding leads to the fact that the oil reserves in the dome remain unselected. The injected water flows to lower, the arched sections of the Deposit.

Lead the development of flooding. After pumping near Central 2 injection wells 0,4-0,7 D. units of pore volume to the nearest rows 3 producing wells stop not less than 90% of wells Central Bank 2 injection wells. The development of lead remaining wells.

According to research for the relevant deposits pumping pore volume of less than 0.4 D. units near Central 2 leads to minor flooding coverage. The nearest production wells series 3 not enough exposed to the system for maintaining reservoir pressure and correspondingly low flow rates. Pumping of pore volume of more than 0.7 D. units. Central next 2 leads to the flooding of producing wells number 3. Less than 10% of wells Central Bank 2 injection wells leave at work due to the fact that some areas with low formation pressures require continuation of injection. Studies have shown that in some areas between rows 2 and 3, the manifold may have a low permeability compared with the entire reservoir 1, which leads to poor displacement of oil from the injection wells to production and accordingly the drop in reservoir pressure. According to the statistics of such sites along Central row 2 less than 10%.

After oil extraction the whole of the Deposit (Deposit 1) more than 90% of the initial recoverable oil reserves between the Central cutting next 2 injection wells and the nearest next 3 mining drill infill wells (4 rows). For this purpose, we first analyze the development of reserves deposits 1. When remaining reserves on any land that falls well out of a number of infill wells less than 15 kt, this well was not drilled because it is economically unprofitable. In the presence of reserves at the site in the amount of 15-25 kt maybe drilling a small diameter. Thus, some of the well sealing 4 rows may be missing.

The injection well itself�about the Central Bank 2 is transferred into the extraction In the upper horizon. Watering up to 98% of wells series 3 is transferred by injection to maintain reservoir pressure.

This approach allows to significantly increase the coverage and recovery deposits due to the selection of oil from the dome of reservoir 1, i.e., rows 2 and 4. The calculations showed that the selection of oil deposits in the whole 1 more than 90% of the initial recoverable oil reserves means that the arched sections of the Deposit is fully developed and all remaining reserves are concentrated in the Central area of number 2. Moreover, the water is injected into the Central row 2 on both horizons at the initial stage of development leads to the fact that according to gravitational separation, almost all the water flows from the dome of the arched area at the bottom of H horizon. In addition, in most cases, lower N, the horizon has a higher permeability than the upper V. Therefore, In the upper horizon along the Central number 2 is the least developed. In this regard, Central injection well number 2 was transferred to the mining operation on the top In the horizon.

The development leads to full economically viable deposits production 1.

The result of implementation of this method is to increase the oil recovery factor of the Deposit (Deposit) through optimization of the development system in time.

Examples of concrete�Togo of the method

Example 1. Oil field presents one big reservoir 1 (Fig. 1). The reservoir 1 has an anticlinal structure. The length of the reservoir is 3.5 km, width - 3,0 km reservoirs are combined into two horizons (upper and lower In N) with terrigenous reservoir (Fig. 2). The roof top of the reservoir lies at a depth of 1620 m. the Central part of the deposits along the major axis, is the dome. Effective net pay thickness In the upper and lower N horizons is 4 to 7 m and 3-6 m, respectively, the permeability layers 300-400 MD and 500-700 MD, respectively. Oil viscosity at reservoir conditions is an average of 5.5 MPa·s, the average porosity of 20%. Initial geological reserves (deposits) are 11760 kt, initial recoverable oil reserves 6068 kt, approved KIN 0,516 D. units.

Along the major axis of the deposits drilled Central cutting range 2 vertical injection wells with well spacing S=300 m. the Central range includes 10 injection wells. Open General filter both the horizon. The nearest row of 3 vertical production wells are drilled at a distance X=500 m from the main series. Each series includes 3 and 8 production wells. Open General filter both the horizon. The rest of deposits 1 razvarivat also be layer system with a triangular grid of vertical producing wells and n�generatelink of wells distance between wells Z=300 m. Production wells are drilled in the amount of 26 wells, injection well in the marginal region of 21 wells.

Reservoir flooding to develop. Injected formation water through injection wells and selected products produced through production wells.

After pumping near Central 2 injection wells 4900 thousand m3the total volume of water that is 0.7 D. units of pore volume to the nearest rows 3 producing wells, stop 9 wells (90%) Central Bank 2 injection wells. The development of lead remaining producing and injection wells.

After oil extraction the whole of the Deposit (Deposit 1) 5470 thousand tons of oil, i.e. for 90.1% of the initial recoverable reserves of oil between the Central cutting next 2 injection wells and the nearest next 3 mining drill infill wells (4 rows). For this purpose, we first analyze the development of reserves deposits 1. Analysis of production showed that the specific residual reserves along the Bank 2 is not less than 15 kt in the well-point. To reduce the cost of infill wells are drilled small diameter.

Analysis of the development of reserves also showed that the water is injected into the Central row 2 on both horizons at the initial stage of development has led to the fact that stocks In the upper horizon was less production of�prisoners who had been due to differences in permeability horizons. Further, all injection wells of the Central Bank 2 is transferred into the extraction on top In the horizon.

During subsequent development wells series 3 irrigate. Upon reaching the water content of 98% producing wells series 3 is transferred by injection to maintain reservoir pressure.

The development leads to full economically viable deposits production 1.

Example 2. Perform as example 1. The distance between the wells of the Central Bank 2 is S=400 m, the nearest number 3 producing wells are drilled at a distance from the Central number 2 at a distance X=600 m, the drilling of the remaining sections of the reservoir is carried out with the distance between the wells Z=400 m. After pumping near Central 2 injection wells share of 0.4 units of pore volume to the nearest rows of production wells, and stop all wells of the Central Bank 2. After oil extraction the whole of the Deposit 95% of the initial recoverable reserves of oil between the Central cutting next 2 and the next closest 3 development wells drilled sealing the series of wells. And in each seal number 4 consists of 4 wells, as the analysis of development of reserves showed the lack of economically viable reserves (over 15 tons) for drilling into the data points producing wells.

As a result of the development, which has limited the watering EXT�linking wells to 98%, it was produced from the Deposit (deposits) 6115 thousand tons of oil, KEANE amounted 0,520. The prototype ceteris paribus produced 5915 thousand tons of oil, KEANE amounted 0,503. Increase of oil recovery factor for the proposed method - 0,017.

The proposed method allows to increase the oil recovery of the Deposit.

Application of the proposed method will allow to solve the problem of increasing oil recovery factor of the field with terrigenous reservoir, represented by two horizons, through the optimization of the development system in time.

Method of oil field development, including drilling of the Deposit layer system with a triangular grid of wells, extraction of oil from production wells, injection working agent in injection wells, transfer of wells into injection and Vice versa, characterized in that at the initial stage of development of the field, the reservoir of which is represented by two horizons, shared between the Central cutting near injection wells with well spacing of less than 300 m, with the Central cutting up some place along the line of the maximum of the structure of the reservoir, injection wells which perform the autopsy General filter both horizons, nearest - the first series of wells are drilled at a distance from the Central range of not less than 500 m, to get so�ivanie other areas of the reservoir is carried out with a distance between holes of 300-400 m, after pumping near Central injection wells 0,4-0,7 proportion of units of the pore volume to the nearest rows of wells stop not less than 90% of the wells in the Central row of injection wells, after the extraction of oil in the whole of the Deposit is more than 90% of the initial recoverable oil reserves between the Central cutting near the injection wells and the nearest adjacent extractive sealing drilled a series of wells, and the wells of the Central row are transferred to an extraction in the upper horizon in flooding of wells of the first row to 98% of their transfer to water injection.



 

Same patents:

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil production industry and can be used during development of pure oil deposits with low-permeable reservoirs. Method of development of low-permeable oil deposits includes drilling of the production and injection wells as per in-line development system using the hydraulic fracturing in all wells. Rows of injection and production wells are arranged in parallel and alternating by one in direction of the maximum horizontal stresses of the reservoir. At that the production and injection wells are drilled with horizontal bores in direction of the maximum horizontal stresses with multi-stage hydraulic fracturing.

EFFECT: increased rate of oil extraction and reduced density of wells grid.

3 dwg, 2 ex

FIELD: mining.

SUBSTANCE: complex includes an underground gas generator; with that, a discharge well is arranged in the centre of a gasified coal section, and supply wells are arranged around it along the periphery of the gasified coal section. Steam-generating equipment includes two spiral pipelines wound about a gas discharge pipe, the first one of which is made in its upper section, and the second one is made below the first one. A receiving hole of the first spiral pipeline is interconnected with a water source, and its outlet hole is interconnected via a connecting pipeline to the receiving opening of the second spiral pipeline. With that, the outlet hole of the second spiral pipeline, which is arranged at its upper point, is interconnected with a steam turbine by means of a steam line. Besides, the steam turbine outlet through a blasting air preparation assembly is interconnected with a supply well that is additionally interconnected with the steam line through a bypass steam line. The bypass steam line is passed through the blasting air preparation assembly with a possibility of ejection of its content; besides, on the surface there arranged is a drying assembly of carbon-containing solid wastes, which is interconnected with their disintegrator, the outlet of which is interconnected with the blasting air preparation assembly. As a CO2 utilisation device, a carbon dioxide production line or a carbon dioxide accumulator having a possibility of its controlled discharge to the blasting air preparation assembly is used.

EFFECT: improving exhaust gas heat utilisation efficiency.

3 cl, 2 dwg

FIELD: oil and gas industry.

SUBSTANCE: method includes drilling and infrastructure development of horizontal producers and injectors crossed in the structure plan, placement of horizontal injectors in the structure plan lower than horizontal producers, perforation of the wells in the productive part with different density, injection of the working fluid to injectors and extraction of the product through producers. According to the invention horizontal wells are placed in parallel to the deposit length and width. At that entry to the productive stratum of producers is placed along one side of the deposit while entry of injectors is placed along the other side perpendicular to the first one. Density of perforated holes at each section of the horizontal wells formed by crossing of producers and injectors in the structure plan is minimum at the cross points and it is increased towards the centre of each section. At the initial stage of development fresh water or water with suspended matters concentration not less than 50mg/l is injected till water cut is decreased in the well. Thereafter stratal or waste waters are injected. Perforation density at the cross points in increased towards the centre of each section on the basis of analytical state considering the well hydrodynamic efficiency against the nature of the horizontal hole opening, distance from the perforated interval up to the horizontal hole of the adjacent well and in-place permeability in the respective perforation interval.

EFFECT: increasing oil recovery factor of the productive stratum and reducing water cut rate of the product in producers.

1 tbl, 2 ex, 3 dwg

FIELD: mining.

SUBSTANCE: proposed method comprises drying of coal seam, injection of oxidiser into reaction channel via vertical injection well, suction gasification products therefrom via gas discharge wells and minimisation of pressure in reaction channel. Note here that, additionally, two vertical wells are drilled to coal seam surface and two vertical 100-140 m long wells are drilled at boundaries of gasified coal seam at 50-60 m from each other. Besides, injection wells are drilled at the center of section under analysis with spacing of 15-20 m. Used oxidiser is atmospheric air with addition of steam-oxygen mix in amount of 20000-50000 m3/h Combustion face temperature is kept up equal to 550-700°C Combustion face is controlled by changeover to injection well which combustion face approaches and by varying the amount of forced oxidiser.

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1 dwg, 1 tbl

FIELD: oil and gas industry.

SUBSTANCE: method lies in drilling of a deposit by vertical and/or directional injection wells and producing wells with crossed and mutually perpendicular boreholes, injection of a working fluid through the vertical and/or directional injection wells and oil extraction through the producing horizontal wells. In two oil-saturated interlayers with matching structural geometry, horizontal boreholes of the producers are made with a length 4 times bigger than the distance between the producers and injectors so that the horizontal boreholes form the grid at cross-sections. 1 or 2 vertical and/or inclined injectors are placed to the centre of each cell. At that a row of parallel horizontal boreholes of the producers is made in one of the oil-saturated interlayers while the other row of parallel horizontal boreholes of the producers is made perpendicular to the first row in the other oil-saturated interlayer in order to create perpendicular filtration flows of one interlayer in regard to the other. The minimum distance between the horizontal boreholes at their cross points in structural geometry is 0.5 m and water-swell packers are envisaged to cut off points of the working fluid breakdown.

EFFECT: increasing coverage of the formation by displacement both in thickness and square area, increasing oil recovery of the productive formation and intensifying percent of oil recovery from the reservoir.

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FIELD: oil and gas industry.

SUBSTANCE: development method of non-homogeneous oil deposit includes drilling as per any famous pattern of vertical, horizontal or directional wells. Borders of zones with various permeability are determined. The well pattern is compacted up to the value of 4 ha per a well. A displacement fluid is injected to each zone through injectors and the product is recovered from the formation in each zone through producers. At that zones with different permeability are divided into low permeable, medium permeable and high permeable. Compaction of the well pattern is made only in low permeable zones. At that the ratio of injectors and producers is selected as at least 1:5 in the high permeable zones, from 1:3 up to 1:5 in the medium permeable zones and from 1:1 up to 1:3 in the low permeable zones. When the flow rate at one zone becomes lower than the commercial production hydrofracturing is made at this site. Then permeability is determined at this site and it is referred to the respective zone with determination of the respective number of injectors and producers.

EFFECT: intensifying recovery in the low permeable zones and increasing oil recovery factor.

1 ex, 1 dwg

FIELD: oil and gas industry.

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7 dwg, 1 ex

FIELD: oil and gas industry.

SUBSTANCE: production zones are determined, producing and injection wells are drilled, oil recovery is made through producing wells and working fluid injection is made through injection wells. At that the four following zones are indentified as production zones: two terrigenous and two carbonate zones, at the end of the second stage of oil deposit development when maximum year oil production parameters start decreasing and measures are performed on year-by-year basis starting since the first year of the method implementation. During the first year two vertical producing wells and one injection well are drilled for the first zone, offshoot is made in the fourth zone from the existing piezometric well, one producing well is switched to water injection in the second zone and one piezometric well is switched to a producing well for the first zone. During the second year one well is switched to injection in the second zone, one well is equipped with installation for downhole pumping from one horizon to another within limits of the first zone, one hole is equipped with dual production unit for the first and second zones. During the third year one well is switched for injection in the first zone, one hole is equipped with dual pumping unit for the first and second zones, two holes are equipped with dual production unit: one from the first and second zones and one from the fourth and first zones; one horizontal offshoot is made at the first zone from the existing producing well, one piezometric well is started up as a producing one for the third zone. During the fourth year one vertical producing well is drilled for the fourth zone; during the fifth year one well from the third zone is witched for production at the fourth zone; during the eighth year one horizontal offshoot is made at the first zone from the existing producing well.

EFFECT: improving oil recovery rate of the deposit by optimisation of its development system.

2 cl, 7 dwg

FIELD: oil and gas industry.

SUBSTANCE: according to the method direction of reservoir-scale fractures is determined, drilling of the deposit by producing and injection wells considering direction of natural fracturing of the deposit, injection of working fluid to the injection wells and product recovery from the producing wells are carried out. Horizontal wells are used. Wells are used as elements of square grid pattern. One side of the square grid is placed along the fracturing direction. Horizontal boreholes of producing wells are placed in parallel to each other in staggered arrangement from the centre of one element of square grid pattern up to the centre of the neighbouring element in the grid placed corner-wise, near the roof of the oil-filled formation. In each producing well, in the productive formation, two water-swellable packers are placed, thus dividing the horizontal borehole into three equal parts. Horizontal boreholes of injection wells are placed in the centre of elements between two parallel neighbouring producing wells and made near water-oil contact or the bottom of the oil-filled formation. Producing and injection wells are made with a certain length of their horizontal boreholes to be determined as per the certain analytical expression.

EFFECT: improving coverage ratio and production rate of the productive formation.

1 ex, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method lies in drilling of directional and vertical wells in shale oil deposit, creation of an ignited zone in them, combustion of a part of hydrocarbon stock, heating of the deposit with combustion products and stripping of shale kerogen in the form of products of shale oil thermal processing. At that a series of non-crossing slant wells directed to shale oil deposit is drilled; to the far end of slant wells igniting straight holes are drilled and oil shale is ignited at their bottom-holes thus creating modules of a slant and straight holes connected hydraulically. Drilled holes in oil shale are processed thermally by counterflow movement of the combustion source from igniting straight hole to the casing of a slant hole thus creating a channel with high drainage capacity. Casing-head tops of straight and slant holes are placed densely at the Earth surface.

EFFECT: maximum extraction of liquid fractions from shale oil deposits.

6 cl, 2 dwg

FIELD: oil and gas industry.

SUBSTANCE: under method the first device is installed in the horizontal well. Firth fluid is injected in the first horizontal well via the first device. HCs production is ensured from the second horizontal well under the first well. Second fluid is injected to the third well shifted to side from the first and second wells to displace fluids in the reservoir to the second well. At that HC production from the second well is continued. Hydraulic connection is ensured between the first, the second and the third wells. Pressure in the first well is increased using the second fluid injected to the third well. First well is closed when its pressure is increased by the second fluid to pressure sufficient to displace HCs from the second well during HCs production.

EFFECT: increased method efficiency.

29 cl, 10 dwg

FIELD: oil and gas industry.

SUBSTANCE: method involves construction of horizontal producers covering the field, and horizontal injectors. Displacement agent is injected through injectors, and products are swept by producers. Horizontal production wells are arranged parallel to each other. Horizontal injector is positioned between horizontal sections parallel to them. Injection starts from bottomhole. When intake capacity of reservoirs is decreased at the bottomhole of horizontal injector to minimum profitable level, non-operating section of horizontal shaft is isolated in series in direction from the bottomhole to the beginning of horizontal injector wellbore. Horizontal producers are drilled in permeable interlayer at 3-6 m distance below the reservoir bottom and at least at 10 m distance above oil-water interface. Horizontal injector is equally spaced from horizontal sections of producers by a design pattern distance. Displacement agent is injected with reservoir pressure rise by 10-20% compared to recovery zone. After time period sufficient to recover and stabilise frontal zone of liquid injected to the reservoir, operation may return to previous intervals. Horizontal sections of producers are broached in two intervals at a distance preventing hydrodynamic connection of the wells. Products are recovered in turns. Production intervals are switched when products reach minimum profitable water cut level.

EFFECT: increased oil recovery due to stabilisation of frontal zone of liquid injected to reservoir, extended application scope of horizontal wells in various field development conditions.

6 dwg, 1 ex

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to the oil-producing industry, in particular to oil field development with flooding. According to the method the displacement agent is injected and oil is withdrawn through the system of injection and production wells. The flooding mode is changed during the development. The displacement agent is injected into the injection well in intensive mode. Using the surface measuring instruments that are a part of an automated process control system the change of extracted oil volume growth depending on the displacement agent injection volume growth until the moment of fast drop of the extracted oil volume is monitored in real time. Then the displacement agent injection volume after which the named drop occurred is recorded. Further injection into the injection well is performed in the volume below this pre-set value.

EFFECT: decrease of labour input of control of oil field flooding process during injection of the displacement agent into injection wells.

1 ex, 6 dwg

FIELD: oil and gas industry.

SUBSTANCE: method provides for use of the production wells. One or several wells are equipped with pump unit with possibility of discharge change. For each production well the deposit or deposits used for production are known. At wellhead of each production well the produced crude oil and oil gas are measured, as well as crude oil watercut is determined. The product wells product is delivered to the gathering header of the wells cluster. The cluster contains one or more injection wells. For each injection well the deposit or deposits used for injection are known. Injectability of the injected water and required injection pressure are determined. Compatibility of the injected water and produced water is studied. Injection is performed upon compatibility of the injected and produced waters. Coordinates of all production and injection wells of the cluster using the same deposits are determined. For each production well time of the produced product lifting is determined from suction of the pump unit to wellhead at maximum discharge. Volume of produced crude oil and oil gas is measured with interval not exceeding half of measured time of fluid lifting for the given well. At wellhead of each well the injected water pressure and its volume are measured. Injected water volume and wellhead pressure are measured with interval not exceeding half of measured time of water supply to the wellhead of each injection well before parker. For each injection well the curve of injected water pressure and volume vs. time is plotted. For each production well using the plotted volume of produced crude oil and oil gas vs. time the relationship with the injected water volume and wellhead pressure is determined, as well as distances to each injection well ensuring injection to the same deposit. For the production wells equipped with pump units with possibility of discharge change such relationships are determined at different discharge. The wells cluster is controlled based on the obtained relationships for all production wells. At that the treated water supply system for injection is made with possibility to change water volume and wellhead pressure for one or more injection wells.

EFFECT: increased efficiency of clusters well control.

2 cl, 1 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: this process comprises measurement of injection well capacity, feed of products of one or several production wells for preliminary water disposal. Measured are density of green oil and gas, green oil water content are measured in the well. Here said products are divided into partially dewatered oil, gas and water. Partially dewatered oil and gas are fed in gathering main. Disposed water is fed into injection well. Compatibility of disposed water with water of seam wherefrom pumping from injection well is made is defined. If threes are compatible, injection well is equipped with the device to create water pressure sufficient for water injection into seam, for example, with electrically-driven rotary pump. Said device allows varying of feed capacity by frequency-controlled drive for said pump. It is set to minimum feed to define the compliance of disposed water quality with the seam geological properties. At poor water quality, it is directed to gathering main or, at sufficient quality, it is forced into injection well. Disposed water amount is defined. Then, device feed capacity is increased either continuously or in stepwise manner to create water pressure. It is increased unless disposed water quality satisfied the seam geological properties.

EFFECT: higher process efficiency.

3 cl, 1 dwg, 1 ex

FIELD: oil-and-gas industry.

SUBSTANCE: this device comprises hollow case with cover that has working fluid feed channels and bottom with discharge channel that features cross-section larger than that of working fluid feed channel for communication case inside with well bottom zone, moving working member that makes with said case the working chambers. Said working member is shaped to truncated ellipse fitted on the case at antifriction bearing and composed of axle with relationship between arms of top and bottom ends equal to 1:2. Aforesaid working member has the channel to communicate working chamber, antifriction bearing with the case bottom discharge channel. Nozzle is arranged under said bottom with communicating discharge channel and radial equal-cross-section area. Total cross-section area of said holes equals that of discharge channel. Cover bottom surface and bottom upper surface are composed of cylinder generatrix to allow displacement of working member top and bottom arms there over and isolation of working chambers.

EFFECT: higher efficiency of stationary pulse injection of fluid.

2 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: method comprises cyclic decrease and increase of pressure in a formation by pumping of water through injection wells and oil withdrawal through production wells. Into the formation through injection wells the mineralised water is pumped periodically in the volume of 0.1-5 of pore volume of the formation and fresh water in the volume of 0.1-5 of pore volume of the formation. The transition to fresh water pumping after mineralised water pumping is performed without gradual decrease in mineralisation. The structure and concentration of salts of the pumped mineralised water are remained at the level of the formation one. The cycle of pumping of waters with different mineralisation is repeated many times. Fresh water is pumped until the moment when decrease of intake capacity of the injection well exceeds the allowable production level - critical drop of reservoir pressure in target impact areas. The mineralised water is pumped until the moment when the injection well sets to initial or close to initial operating mode which depends from the flow rate of the injected liquid and well head pressure.

EFFECT: increase of oil recovery of formations due to increase of their coverage.

2 dwg

FIELD: oil and gas industry.

SUBSTANCE: method comprises run in the production well below fluid level of the pipes string with pumps, and with filters installed at pipe ends, product recovery from top production deposit, oil and water separation in the wellbore, water injection to the bottom deposit, oil lifting to surface. Two filters are run to well on separated pipe strings. Filters are pipes with capillary holes with diameter 2 mm max, and density 50 holes/m min. One filter has hydrophobic surface with hydrophobic degree 99% min, the another filter has hydrophilic surface with hydrophilic degree 99% min. Parker is installed above the top deposit to seal the annulus. Filters are made with length not below the bottom deposit roof. Filter with hydrophilic surface is made with large length then the filter with hydrophobic surface such that the parker installed between the production string and filter with hydrophilic surface will be above the bottom deposit roof, and end of the filter with hydrophobic surface will be above this parker. The parker does not permit the fluid from the top deposit flow to the bottom deposit via the annulus. Moving from the top production deposit to the wellbore the fluid enters the annulus, where it is filtered via the capillary holes of the appropriate filters with hydrophobic and hydrophilic coatings separating to oil, that entering via the filter with hydrophobic surface in the pipes string by the pump is lifted to surface, and to water that entering via the filter with hydrophilic surface in the another pipes string by the pump is pumped in the bottom deposit.

EFFECT: increased efficiency of oil and water separation in the wellbore, increased efficiency of waterflooding and increased oil recovery of the deposit.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method comprises run in the production well of the pipes string with filter below liquid level in well, product recovery from top deposit, oil and water separation in the wellbore, water injection to bottom deposit, oil lifting to surface. The filter is pipe in pipe, the internal pipe has hydrophilic surface with hydrophilic degree 99% min, capillary holes with diameter 2 mm min, and density 50 holes/m min. Outside pipe has hydrophobic surface with hydrophilic degree 99% min, capillary holes with diameter 2 mm max, and density 50 holes/m min. Pipes string diameter used for filter run is equal to diameter on internal filter pipe. Internal pipe has length exceeding length of outside pipe. Outside pipe is located not below the top deposit, and internal pipe - not below bottom deposit. Between the casing string and bottom of the outside pipe above the top deposit the parker is installed, ensuring fluid from top deposit ingress directly in space between the internal and outside pipes of the filter. Between the casing string and bottom of the internal pipe above the bottom deposit the parker is installed also, excluding fluid from bottom deposit ingress in space between the internal and outside pipes of the filter. Moving from top production deposit to the wellbore the fluid enters the space between the internal and outside pipes of the filter, where it is filtered via the capillary holes of the appropriate filter pipes with hydrophobic and hydrophilic coatings, separating to oil that entering in the outside pipe and then in annulus by the pump is lifted to surface, and to water that entering in the internal pipe by the pump is pumped in the bottom deposit.

EFFECT: increased efficiency of oil and water separation in the wellbore, increased efficiency of waterflooding and increased oil recovery of the deposit.

2 dwg

FIELD: oil and gas industry.

SUBSTANCE: system includes a group pumping station with a pump feeding water line with a pressure sensor, a water discharge line of the pump, a valve manifold, a system of distributing water lines downstream the pump with flow meters, shut-off and control valves, low-permeable injectors with return valves and high-permeable injectors. At that the system operates in a cyclic mode with cycles of pressure increase and decrease in the feeding water line. The high-permeable injectors are equipped with spring-operated flow controllers. At the water line feeding the pump there is a pressure controller bound with a bypass line with a flow controller and automatic gate. This gate is coupled functionally with a cluster controller. It ensures the collection of data from the flow meters and pressure sensor with the analysis of the performed task against pressure injected through the distributing water lines. The automatic gate is made so that at the r signal of the controller it provides the water flow through the bypass line in order to compensate water injection to the low-permeable injectors at the total deficiency in the injection volume to them.

EFFECT: excluding deficiency in the injection volume to the low-permeable injectors and pressure balancing in feeding water lines.

1 dwg, 1 tbl

FIELD: oil and gas production.

SUBSTANCE: groups of high intake- and low intake-capacity injecting wells are chosen in a single hydrodynamic system and, for each well, oil reservoir properties and permissible degree of pollution of fluid received by high intake-capacity wells are determined. When fluid from low-permeable oil reservoir flows off through high intake-capacity wells, this fluid is cleaned to permissible degree of pollution.

EFFECT: reduced losses in intake capacity of formations and increased time between treatments of wells.

1 dwg

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