Oil deposit development method
FIELD: oil and gas industry.
SUBSTANCE: according to the method geophysical survey of exploratory wells is performed by crossed dipole shear sonic imager. Oriented core is selected with further determination of directions of natural fracturing. Regional directions in maximum stress of oil-saturated rock are defined. According to findings injectors are placed along the regional directions in maximum stress. Producers are placed in between injectors thus forming developing method. Part of injectors occurred in fault zones and closer than 200m is introduced into operation as producers with their further transfer to injectors. When watering is higher than break even point and when it is required to maintain reservoir pressure at the deposit producers are transferred to injectors. Transfer of wells is made so that they form rows of injectors step by step along regional directions in maximum stress of oil-saturated rock and provide even oil displacement.
EFFECT: increased reservoir recovery due to more efficient and sound placement of well pattern within the area of oil deposit considering tectonic and geomechanic conditions of pay rocks occurring.
3 cl, 3 tbl, 8 dwg
The invention relates to the development of oil deposits using the methods of oil displacement from the reservoir water, in particular to the development system, depending on the geomechanical conditions of occurrence of productive breeds. Represents the choice of the optimal location of wells on the area of hydrocarbon reservoir taking into account the azimuthal orientation of the maximum stress breeds. The method includes geophysical surveys of wells, such as cross-dipole acoustic logging to determine the anisotropy of the azimuthal stress distribution in productive formations, microseismic monitoring during hydraulic fracturing to determine the direction of propagation of cracks, which coincides with the direction of maximum stress of the formation, research oriented selected core in the area of natural fracturing of rocks if available, the identification of disjunctive dislocations within the oil field.
Known widely used method of areal system of oil fields, the most common of which are five-, seven-, deviationa. The elements of the system with five-point design schema is a square, the corners of which are producing wells, and in the center - discharge. With�the ratio of injection wells to production - 1/1. When seven-point scheme development element of the system is a hexagon with producing wells in the top of the injection in the center. The ratio of injection wells to production - 1/2. When devyatietazhnoe the scheme of development the ratio of injection wells to production - 1/3 (Zheltov, Y. P., oil field Development: Textbook for universities. - 2-e Izd., revised and enlarged. - M.: JSC "Publishing house "Nedra", 1998).
The disadvantage of this approach to system development is the location of the wells without consideration of the geomechanical properties of the reservoir/reservoirs, in particular the distribution of the directions of maximum stresses, and the location of tectonic disturbances. Areal development system more rigid, does not allow to use other injection wells from element of the system without disturbing the geometrical orderliness of wells location. This leads to a greater reduction of oil recovery factor due to dagger and linguistic breakthrough of injected water to the faces of producing wells in almost all conditional rows in the directions of maximum stresses of the rocks and along tectonic faults, reducing waterless period of operation, the appearance of a large number of sites with high residual oil saturation, not involved in the development
A method of developing oil fields (copyright certificate №1806262 from 30.03.93 G., EV 43/30, 43/20, Bulletin No. 12 of 30.03.1993 g), where for the purpose of eliminating these disadvantages is provided by: establishing on the area of the reserves systems of faulting of the reservoir, the drilling of production and injection wells on the area of deposits, extraction of hydrocarbons through the production wells located within the systems faults at an equal distance, and injection wells are placed outside of faulting. Also known method (copyright certificate №1806261 from 23.12.91 G., EV 43/30, 43/00, Bulletin No. 12 of 30.03.1993 G.), in which at the stage of exploration to drilling production wells on the basis of data from space and aerial photography of the territory, seismic surveys for reservoir construction of a map of system faults, the results of which shall determine the location for drilling of wells within the zone of faulting with subsequent drilling and producing of oil and gas.
The known method of development of deposits of hydrocarbons in fractured reservoirs (copyright certificate №2148166, EV 43/30 from 27.10.2000), which carried out the complex of geophysical and borehole investigations, based on the data we are building seismic sections and their paleoreconstructions, determined by him GE�the logical bounds of the productive strata. Set the location of zones of faulting, allocate zones of neotectonic movements of the formation. Drilled productive wells near faults. A method of developing oil fields (copyright certificate №2292453 from 27.01.2007 G., EV 43/30, 43/16), in which the set on the square of the hydrocarbon reservoir location of system faults, post producing wells near them, and injection wells outside or within the areas bounded by these faults, determine the hydraulic connection faults with wells and/or other faults of the composition extracted from them fluids-hydrocarbons and water, filtration control resistances between wells and faults and, when the inflow of water due to the contour of the oil and gas or injection wells, increase filtration resistance between wells and faults by injection waterproofing compounds through producing or injection wells or through wells that are drilled on the contour of oil near discontinuities in the flow lines of the water, thus translate well from one category to another; production wells are placed in parallel to tensile violations at a predetermined distance with anisotropy PR�nizamate layer in different directions; post production wells close to the intersection of several faults in producing wells that are not related to violations of the system of cracks, reduce filtration resistance between wells and faults directed perforation, hydraulic fracturing, horizontal wells and sidetracks, physico-chemical exposure; post injection wells in the inner part of oil-saturated zone bounded by faults, the mesh density is chosen inversely proportional to permeability was found taking into account the anisotropy in different directions and translate these wells at the initial stage in producing wells; placing wells on multi-horizon field by selecting their profile closer to zones of faulting; production wells are placed without intersection with faults, the intersection is carried out in a hydrocarbon reservoir horizontal shaft, a Spud in the side of the barrel, hydraulic fracturing; well placed between adjacent hydrodynamically unrelated faults, connecting the past with the well by drilling it extra barrels, with one or several trunks of the wells are used for production of hydrocarbons, and the other by injection waterproofing compounds or�to a discharge; in the layers determine the hydraulic connection faults with wells and/or other faults of constant monitoring, taking into account the system of cracks and channels with low filtration resistance change the location of production and/or discharge; the location of the discontinuities is set according to aerogeophysical research, land seismic, spectral seismic profiling, determining in the sample the content of tin (Sn), chromium (Cr), cobalt (Co) and their relations Sn/Cr, Sn/Co, while drilling on cavernosometry and the rate of change of absorption of drilling fluid, after drilling through vertical seismic profiling, interference testing, tracer studies, the temperature variation along the borehole depth, acoustic methods, the method of adaptation of a geological-hydrodynamic model, I specify the position of faulting geophysical methods; determine the source of oil in the reservoir of oil source rocks.
The disadvantage of these solutions is the lack of ideas of adaptability of placing wells on the area of oil field with anisotropy of the azimuthal distribution of values of horizontal stress in productive formations, improper location of production and injection wells outside of tectonic disturbances, within "traditional" development system, are not considered deposits of hydrocarbons without tectonic disturbances.
A method of developing oil fields (copyright certificate №22911955 from 20.01.2007 G., EV 43/16), in which the set of the centers of seismic activity and the distribution of fracture for each productive stratum, in the process of developing a register area of the seismoacoustic emission and in real time, in the aggregate, the changes seismoacoustic emission and indicators of development of the field, in particular Isobar maps and water cut wells, identify poorly drained, stagnant and flushed zone, changing the direction of filtration flows, initiate and intensify additional cracking in poorly drained and stagnant zones to the level registered noise; for changing the direction of filtration flows serves to adjust the mesh density of wells and development system, to organize new sources of flooding, to drill additional wells and sidetracks, to establish a base of production and injection wells relative to the direction of fracture in the design elements, which mostly perpendicular to the strike of the cracks oil is displaced, in particular in radn�th element in the development of injection wells, including horizontal and lateral trunks, situate on the line of the direction of fracturing, and production wells, including horizontal wells and sidetracks, is parallel to this line; it is assumed the permanent or periodic effect on the accumulation of physical radiation with excitation and propagation in the geological environment of the waves elastic waves, electromagnetic waves, impulses for additional fracturing in poorly drained and stagnant zones.
The disadvantage of this method is that are considered deposits with fractured and fractured-porous reservoirs under development, identify poorly drained and stagnant zones, direction of fracture, optimize the existing system design seal mesh, drilling additional wells and sidetracks with the aim of changing directions of current flow filtration in the process of development. Location of injection and production wells, including horizontal and sidetracks, directions parallel to the fracture is only intended for additional wells to develop the deposits and on sections or individual elements, where the data of wells formed line-system development. Not considered all of the Deposit as a whole, are not considered deposits of carbohydrate�childbirth, having a pore collector with no fracture or slight amount, there is no idea of the adaptability of placing wells on the area of oil field with anisotropy of the azimuthal distribution of the values of the regional horizontal stress in productive formations that improve the efficiency of development, to reduce the share of poorly drained and stagnant zones since the beginning of the development, additional physical impact on the productive formations.
The objective of the proposed method is to increase the efficiency of development of deposits of hydrocarbons in comparable investments that have "standard" systems development, increasing the rate of oil recovery from the reservoir, which is achieved due to a more efficient allocation of production and injection wells in the field area taking into account the geomechanical and tectonic conditions of occurrence of productive breeds.
The task is achieved by the fact that the way to develop hydrocarbon deposits place hydrocarbon reservoir location of discontinuities and anisotropy distribution of tension productive breeds, namely the azimuthal orientation of maximum horizontal stress. Tectonic disturbance of�determined: prior to drilling based on seismic data 3D/2D; during drilling, using the caliper measurements, as well as the rate of change of absorption of drilling fluid. The direction of maximum stresses are defined: before drilling, be accepted by analogy with neighbouring developing oil fields with similar reservoir; drilling of exploration wells and the first production wells oriented away by the depth of rock core from the target reservoir interval with subsequent determination of the azimuthal orientation of the natural fracture; after drilling exploratory wells are conducted geophysical studies of cross-dipole acoustic logging (determine the geomechanical properties of rocks, the direction of natural fracturing by measuring the velocities of longitudinal and transverse acoustic waves), when well stimulation using hydraulic fracturing also perform microseismic monitoring. Based on these data, the injection wells are placed along the azimuthal directions of the maximum stress producing formations. In case of detection of a zone of faulting, injection well, located in the immediate vicinity of the breach, less than 200 m, is started into operation as mining with the development of the oil to increase the water content of produced fluids �ore than 95%, and/or above the threshold of profitability under prevailing at the time of execution of works of the production cost of oil, and/or when necessary to maintain reservoir pressure in operation. Then the well is transferred by injection of the displacing agent or piezometric Fund for the control of energy development in the area of the fault. In the process of development of the field is held constant monitoring of the traffic flow filtration, clarifies the provisions of faulting, local direction of maximum stress. Establish pressure communication between the injection and producing wells, injection of tracer agents, interference testing, geologic analysis, etc. based On the obtained data on the zones of tectonic disturbances, local features of the distribution of the directions of maximum stresses conduct adjustment system development: translate part of wells from one category to another - mining in injection, injection into production. While injection wells trying to print beyond the zones of tectonic disturbances and to eliminate the location of producing wells azimuth in line with injection wells in areas of maximum stresses breeds.
Technical results�the ATA is to increase the oil recovery factor, the increase in the rate of oil withdrawal, is achieved by placing wells on the area of oil field subject to the directions of maximum stresses productive breeds, the presence of tectonic disturbances.
The method consists in the following. Conducted numerous studies, such as cross-dipole acoustic logging, microseismic monitoring of hydraulic fracturing, tracer test, interference test, geologic analysis of injection and production wells, at various oil fields in Western Siberia, show that the promotion of basic amount of injected water and the manifestation of the highest speeds in the reservoir occurs in the directions of maximum stress breeds. In these directions also apply the cracks of hydraulic fracturing and oriented natural fractures if it is available. Production wells are located azimuthally in the same directions relative to injection wells, and irrigate in the first place and often abnormally in the shortest possible time. The growth rate of watering sharper relative to neighboring wells located perpendicular to the line of maximum stress. In zones of tectonic disturbances and adjacent areas, no more than 200 m, op�Adelino geophysical logs and geologic analysis, the regional direction of maximum stress changes its direction until the coincidence with the direction of the development of these disorders.
Fig. 1, Fig. 2 shows a three-row versions of the development system, respectively, with the traditional scheme of arrangement and the proposed method. Fig. 3, Fig. 4 show variants areal seven-point development system respectively when the traditional scheme of arrangement and the proposed method. Fig. 5 shows a variant of the proposed method seven-point development scheme, which will be given to this type after leading irrigation production wells azimuth in line with injection wells in areas of maximum stresses of rocks and the subsequent transfer of irrigated production wells into injection. On all schemes of development injection wells designated four-pointed figure - POS. 1, producing a circle - POS. 2, faults dashed line - POS. 3, the azimuth direction of the regional maximum stress productive breeds arrow - POS. 4, the lines of the rows of wells with line - POS. 5, production wells are converted to injection after reaching threshold values of water content, - four-pointed figure - POS. 6.
Placing the rows of injection �of Quain of the proposed method along regional areas of maximum stresses creates more uniform waterflood front. Initially the injected agent moves along the line of injection wells through the channels of natural fracturing, creating cracks "of autoregressive formation", in the shortest time, reaching discharge zones nearby wells. Then begins the increased movement in directions toward producing wells in which the predominant effect of the piston displacement. Reduces dagger breakthroughs agent exposure to the faces of producing wells, increasing their waterless period, increases the oil recovery factor.
To determine the effectiveness of the claimed method the calculations were carried out on pie plot geological-hydrodynamic model of the Jurassic deposits of deposits of Western Siberia, characterized by low PV system layer that implements the areal seven-point system design without considering the directions of maximum stresses. The model is constructed in the software package "ROXAR", reservoir simulation development process was carried out using certified software complex v Tempest MORE.6.7, passed testing of the SPE in accordance with the requirements of "Regulations on modeling and is widely used both in Russia and abroad. For the numerical simulation of the development process used�Valas model "black" oil. The procedure of averaging of reservoir properties was carried out by weighing appropriate volumetric characteristics in the software package IRAP RMS. Calculations of indicators of development of the reserves was based on the actual technological modes of production and injection wells in the period from the beginning of 2006 to develop 01.01.2025 G. with the step of sampling indicators the 1st quarter.
On this site drilled and operated 29 wells. The proposed method of development does not change their number. Tectonic disturbances according to the 3D seismic was not detected. The filtration parameters of the model area are presented in table 1, geological and physical characteristics of the productive formation YUS-1 - in table 2, relative permeability - Fig. 4. The effectiveness of the proposed method is determined by comparing calculations of the accumulated oil production, shown in Fig. 5 and table 3, which show that in the fifth year of development, the pace of oil extraction according to the new plan start ahead of the baseline and at the end of the billing period, the excess is 107,7 thousand tons. The increase in oil recovery efficiency occurred at 10%. Fig. 6 shows a residual oil saturation of a formation on the end date of the calculation of the basic and proposed development to which�Oh we observed complete depletion of reserves of oil on the area in which the proposed scheme of arrangement of wells, taking into account the distribution of the directions of the regional maximum stress seams relative to the base.
Application of the proposed method in the oil industry will:
- to increase the coverage of the developed reservoir flooding area;
- to increase waterless period of operation of wells;
- increase the rate of extraction of oil;
- to increase the recovery factor of oil without additional capital investments.
1. Method of oil field development, characterized by the fact that carry out geophysical studies exploration wells using cross-dipole acoustic logging, select the oriented core with subsequent determination of areas of natural fractures, determine the regional direction of maximum stresses of oil-saturated rocks, the results are placed injection wells along regional areas of maximum stresses between injection wells production wells are placed with the formation of the development system, part of injection wells within the zone of tectonic disturbances and closer than 200 m, is placed into operation as mining and subsequent conversion under injection wells, production wells, when flooding above the threshold of profitability and required�and maintain reservoir pressure in the reservoir, transferred into injection wells and so that they gradually formed a complete series of injection wells along regional areas of maximum stress of oil-saturated rocks and provide uniform displacement of oil.
2. A method according to claim 1, characterized by the fact that during stimulation of oil conduct hydraulic fracturing microseismic monitoring.
3. A method according to claim 1, characterized by the fact that in specifying the characteristics of the regional distribution of the directions of maximum stresses of oil-saturated rocks conduct adjustment of the development system, for which production wells are transferred to the discharge, and the discharge - producing, injection wells must be outside the zones of tectonic disturbances, and production wells should not be on the same line to the injection wells in areas of maximum stresses of oil-saturated rocks.
FIELD: oil and gas industry.
SUBSTANCE: group of inventions relates to the field of oil industry and can be used for enhanced oil recovery of the reservoir in the development of water-flooded reservoirs with viscous oil and bitumen at a late stage of development. The method comprises opening the reservoir with the ability to transfer the production well into the injection one, the reservoir processing, keeping the hole without any influence, intake of oil from the reservoir. At that a system of microwave electromagnetic generators with radiation frequency of 2.5 GHz is lowered into the injection well, connected to the slot antenna using the feeder. The length of the slot antenna is selected equal to the thickness of the aquifer of the reservoir. In the mode of injection, the water injection into the reservoir is carried out with simultaneous influence on the reservoir with microwave electromagnetic field, the radiation power is determined by the time of heating of the water injected in the downhole to the desired temperature. When filling 5-10% of the volume of the pore space of the formation, the well is maintained, the well is transferred into the production well, and the liquid intake from the production well is carried out.
EFFECT: increase of the effectiveness and economical efficiency of development of water-flooded reservoirs of high-viscosity oil, intensification of oil production in water-flooded reservoirs of high-viscosity oil by increasing the coverage with influence to the reservoir with heating in the bottomhole area of the reservoir of the production wells.
2 cl, 3 dwg
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
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.
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.
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.
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.
FIELD: oil and gas extractive industry.
SUBSTANCE: method includes construction of wells and oil and gas collection system, forcing water from water-bearing level into oil deposits, flow of oil from oil deposits into secondary deposit and following extraction of oil from secondary deposit for useful implementation. Resources of deposit are separated on basis of natural energy characteristic on screened and having rigid water-forcing mode. Deposit is operated by three well types. Of the latter flow wells connect oil deposits to secondary deposit for flowing and collection of oil in upper bed under effect from gravitation. Balancing wells connect screened deposits and secondary deposit to water-forcing level for balancing of bed pressures and preventing loss of rocks stability. Extraction wells connect secondary deposit to oil and gas collection system. Selection of bed for secondary deposit is performed from number of highly penetrable beds, having maximally allowed excess over oil deposits.
EFFECT: higher oil yield, higher effectiveness.
5 cl, 3 dwg
FIELD: oil extractive industry.
SUBSTANCE: method includes drilling of deposit according to row-wise non-even grid of wells with distance from force to extractive rows, greater than distance between extractive rows, pumping of displacing gent into force wells, extraction of product from product wells and transferring of displacing agent pumping front to extraction area. According to invention, transferring of displacing agent pumping front to extraction area is performed by drilling side horizontal shafts in all wells of force row and directed towards extractive row by beds ad zones with most remainder oil saturation level. Then among these wells are singled out, horizontal shafts of which pass along beds and areas with lesser oil saturation level. Pumping of displacing agent is restarted, and other wells are transferred to product category. These wells are operated with face pressures lower than saturation pressure until reaching 98% water saturation level. After that pumping of displacing agent is restarted along all other wells of force row. During that, rows of extractive wells are operated in normal mode.
EFFECT: higher efficiency.
FIELD: oil industry.
SUBSTANCE: according to first variant of method, force and product wells are drilled, working agent is fed through force wells, oil is extracted through product wells, dome-like raised portions are marked out, which surpass absolute marks of bed, additional wells are positioned in these portions. Wells placement is planned at tops of dome-like raised portions even with breach of evenness of planned well mesh. After full drilling of wells mesh and in case of more accurate definition according to data of drilled wells of deposit of dome-like portions side shafts are drilled from adjacent wells towards more precisely defined tops of dome-like portions, controlling the deposit. In adjacent wells and side shafts, positioned on tops of dome-like raised portions , range of productive bed is opened between absolute mark of ceiling in this well and absolute mark, appropriate for ceiling in closest well. According to second variant of method practically analogical operations are realized as in first variant, except when absolute mark of ceiling of productive bed according to adjacent wells is lower than mark of sole of productive bed, whole bed is opened in side shafts.
EFFECT: higher efficiency.
2 cl, 2 dwg
FIELD: oil reservoir development, particularly for developing water-flooded ones.
SUBSTANCE: method involves withdrawing oil through production wells and ejecting working substance through ejection wells. To prevent water ingress from well bore into oil-saturated formation area formation is perforated in water-oil interface zone so that lower part of oil-saturation formation interval and upper part of water-flooded formation interval are penetrated. This provides oil relative permeability retention in oil-saturated formation area. To prevent formation mudding during initial perforation thereof drilling is performed in depression, balance and repression modes with pressure of not more than 3 MPa. As far as oil is depleted perforation interval is extended towards oil-saturated formation area.
EFFECT: possibility to retain oil relative permeability of oil-saturated formation area.
2 cl, 2 dwg
FIELD: oil field development, particularly for ones with nonuniform reservoirs.
SUBSTANCE: method involves drilling injection and production wells; flooding oil reservoir and extracting oil out of well; defining more exactly geologic aspects on the base of drilling results; designing and drilling additional wells with horizontal bores or drilling horizontal bores from existent wells; determining location of reservoir drive zone boundaries; calculating volume of dead oil located near drive zones; drilling horizontal bores from existent wells located near drive zones and/or new wells with horizontal bores located in above zone, wherein horizontal bores are drilled in direction perpendicular to drive zone boundaries.
EFFECT: improved oil recovery.
2 dwg, 1 ex
FIELD: oil industry.
SUBSTANCE: method includes drilling vertical product and force wells, extracting oil from product wells, forcing working agent through force wells, making side horizontal shafts in force wells, forcing working agent through side horizontal shafts of force wells. Additionally, side horizontal shafts are made in extraction wells. Oil is taken through side horizontal shafts of extractive wells. With pressure in the well, decreased for 5-10% from hydrostatic pressure, all side horizontal shafts are made by washing away rock under pressure of fluid of around 15-20 mPa. Direction of all side horizontal shafts is set to be parallel to rows of wells.
EFFECT: higher oil yield.
1 ex, 1 dwg
FIELD: oil production industry, particularly enhanced recovery methods for obtaining hydrocarbons.
SUBSTANCE: method involves drilling production and injection wells and maintaining formation pressure; performing seismic works to determine volumetric routing of natural macrocrack system with lateral and depth routing; forming production and injection macrocracks of above system; drilling wells to corresponding macrocracks and forming producing well-macrocrack systems for oil production and injection well-macrocrack for formation flooding or production well-macrocrack for oil production and system including vertical and/or horizontal multibranch wells for formation flooding or injection well-macrocrack system for formation flooding and system including vertical and/or horizontal multibranch production wells for oil production or production well-macrocrack system, injection well-macrocrack system and system including vertical and/or horizontal multibranch production and injection wells.
EFFECT: increased efficiency, oil recovery and production well injectivity, as well as increased sweep efficiency and oil recovery ratio.
FIELD: oil production industry, particularly oil deposit development.
SUBSTANCE: method involves pumping working agent, namely water, in two stages. The first stage is performed with the use of power pumps. The second one is carried out by means of hydraulic measuring pumps, which are used to convert injection pressure created by power pumps. If it is necessary to increase pressure in water lines used to deliver water to separate injection wells pressure is regulated in accordance with necessary water volume to be injected in wells on the base of collecting properties of oil formations in bottomhole formation zones. This is performed by providing change in pump piston diameter and stroke ratios in the first and the second sections of hydraulic measuring pumps, which are selected on the base of hydraulic resistance variation depending on water flow velocity. Parameters characterizing injection system operation are simultaneously measured and efficiency of the method and equipment operation is detected from above characteristics.
EFFECT: increased efficiency of oil bed development due to energy-saving equipment and technique usage for formation pressure maintaining.
2 cl, 2 dwg
FIELD: enhanced recovery methods for obtaining hydrocarbons.
SUBSTANCE: method involves flooding production bed through injection wells with the use of pump units. In the case of terrigenous porous productive bed flooding acoustical sound resonators with resonance frequency setting are installed in injection line. This eliminates amplitude of alternating low-frequency liquid pulsation sound generated by pump units. Method also involves providing constant compression mode in productive beds and frontal oil drive from productive bed.
EFFECT: increased operational reliability.
1 ex, 3 dwg