The way to develop low-permeability oil and gas or gascondensate-oil deposits

 

The invention relates to the oil and gas industry and may find application in the development of tight oil and gas or gascondensate-oil deposits. Provides increased productivity of oil wells. The inventive method includes wiring in podgotovki zone deposits horizontal / directional wells with their perforations with the location of their top of the perforated interval above the gas-oil contact - STC at a distance of from 0 to 20 m Lower perforation interval feature in podgotovki or oil zone. The development of deposits are maintaining pressure by injection of working agent or mode of gas repression. Moreover, with the development of deposits on the mode of gas repression produce periodic measurement of gas-liquid factor, above which more than 600-700 m3/t the upper perforation interval horizontal and inclined wells lowered to achieve this magnitude of gas-liquid factor. The lower perforation interval horizontal and inclined wells have in the region of the STC. 2 C.p. f-crystals, 2 tab., 8 Il.

The invention relates to the oil and gas industry and may on the walls of the method of extracting oil from podgotovki zone oil and gas reservoirs in the system producing horizontal and/or vertical wells, the relationship between the production well carried out on sections of an oil rim with a relatively high filtration resistance between the filter and gas and/or oil-water contacts [1].

There is a method of oil production, if it is carried out in low-permeability reservoirs, reduces oil production. Reduced oil production and productivity of wells for oil.

The closest in technical essence of the present invention is a method of developing a low-permeability oil and gas or gascondensate-oil fields, including transaction deposits in wells with perforations and selection of oil [2].

The disadvantage of this method is the low productivity of oil wells.

The invention solves the problem of increasing the productivity of oil wells.

The task is solved in that in the known method the development of low-permeability oil and gas or gascondensate-oil deposits, including transaction deposits in wells with perforations and selection of oil, according to the invention is conducted horizontally-inclined wells in podgotovki zone deposits with the location of their top of the perforated interval above the gas-oil contact at a distance of from 0 to 20 m, and the lower intania by injection of working agent or mode of gas repression, and also the fact that during the development of deposits on the mode of gas repression produce periodic measurement of gas-liquid factor, above which value more than 600-700 m3/t the upper perforation interval horizontal and inclined wells lowered to achieve this magnitude of gas-liquid factor. The lower perforation interval horizontal and inclined wells have in the field of gas-oil contacts.

The essential features of the invention are.

1. Transaction deposits in horizontal and inclined wells.

2. Transaction deposits in wells with their perforation.

3. The selection of oil.

4. Conducting horizontal and inclined wells in podgotovki zone deposits.

5. The location of the top of the perforated interval above the gas-oil contact at a distance of from 0 to 20 M.

6. The location of the bottom of the perforated interval in podgotovki area or the oil zone.

7. The development of deposits of lead in the pressure support mode by injection of working agent or mode of gas repression.

8. During the development of deposits on the mode of gas repression produce periodic measurement of gas-liquid factor.

9. When the excess of the gas-liquid factor 600-700 m3/t the upper interval perfor the Lower perforation interval feature in the field of gas-oil contacts.

Signs 1-3 are common with the prototype of significant signs, signs 4-7 are the salient features of the invention, and signs 7-10 are additional essential attributes.

The essence of the invention.

In the known technical solutions in the development of low-permeability oil and gas and gazokondensatnyh deposits wells perforated upper perforation interval is placed on an indefinite distance from the gas-oil contact, which reduces their productivity on oil. Therefore, the proposed technical solution is conducted horizontally-inclined wells in podgotovki zone deposits with the location of their top of the perforated interval above the STC on the distance from 0 to 20 m, and the bottom of the perforated interval in podgotovki or oil (which is not the gas cap, there is no STC) zones. This limits the placement of the top of the perforated interval of the wells corresponds to the maximum value of oil production. When the gas is supplied in small quantities from low-permeability layer at the top of the perforation interval of the wells, plays the role of the internal gas and contributes to the rise of oil.

If the location of the bottom of the PR interval>Then the gas from the gas cap will flow into the well through the top and bottom perforation intervals, partially dissolved in the oil, increasing its volume and thereby contributing to the rise of pressure (it is known that the extraction of oil from low-permeability reservoirs reservoir pressure in the production well is declining rapidly). Thus, it provides a dual gas lift and increases the productivity of the well production.

However, in this case (placing the bottom of the perforated interval in the field STC) when developing on the mode of gas repression by expanding gas cap is being reduced STC, which, naturally, determines the excess of the bottom of the perforated interval of the wells above the level of the STC. In this regard, shall move the bottom of the perforated interval to the level of detection (for example, by isolating the lower exposed above the STC, the perforated interval of the well). Thus, the lower perforation interval will always be in the field GNK.

The Deposit will be developed with maintaining pressure (reservoir) by injection of working agent (water or gas) or gas mode repression, i.e. depletion. In the latter case there is decrease in the level of the STC during the expansion of the gas cap that privode mode gas repression produce periodic measurement of gas-liquid factor. If its value exceeds 600-700 m3/t the top of the perforated interval is lowered until the value of gas-liquid factor 600-700 m3/so This value corresponds to the maximum value of oil production.

The invention is illustrated in the drawing, where:

in Fig. 1 shows a section of oil and gas deposits under the regime of the gas repression, with a horizontally-inclined borehole at the location of the top of the perforated interval above the STC, and lower in podgotovki area;

in Fig.2 shows a section of oil and gas deposits, developed by maintaining reservoir pressure, with a horizontally-inclined well with the location of the top of the perforated interval above the STC, and the lower oil zone and injection wells;

in Fig.3 shows a section of oil and gas deposits under the regime of the gas repression, with a horizontally-inclined bore and the location of the top of the perforated interval above the STC, the bottom of the perforated interval in podgotovki zone, in the region of the STC;

in Fig.4 - shows a graph of flow rates of the two horizontal wells with the location of the top of the perforated interval in one of the wells above the STC and the other below the STC, the years of development;

in Fig.5 - grafy the flow rate of oil and gas-liquid factor by years of development;

in Fig.7 is a diagram showing changes in the gas-liquid factor depending on the distance above the STC;

in Fig.8 is a graph of flow rate of oil from the gas-liquid factor for flowing horizontally-inclined wells of the Eastern block of the Orenburg field with the top of the perforated interval in the field GNK.

The method is as follows.

Development of low-permeability oil and gas or gascondensate-oil deposits includes wiring in podgotovki zone deposits horizontal and inclined wells. Their upper perforation interval feature on the STC on the distance from 0 to 20 m, and the lower perforation interval in podgotovki or oil zones. The development of deposits carried out by maintaining the pressure (reservoir) by injection of working agent (water or gas) through the injection well (Fig.2) or on the mode of gas repression (Fig.1).

The oil under the effect of reservoir pressure is supplied to the horizontally inclined hole, and the gas flowing through the upper perforation interval of the gas cap, plays the role of the internal gas and contributes to the rise of oil. During the development of deposits on the mode of gas repression changing the distance from the top of the perforated interval is the actor. Produce periodic measurement of its magnitude. When the well is stopped and the excess of the gas-liquid factor 600-700 m3/t the upper perforation interval lower and including a well, again measured gas-liquid factor. The procedure is repeated until then, until the liquid factor reaches the value of 600-700 m3/t at which the flow rate is maximum.

At the location of the bottom of the perforated interval in the region of the STC (Fig.3) in the above activities and reduce the STC is the projection of the bottom of perforation interval over STC. In order to maintain the specified spacing of the perforations in the region of the STC, his move to this area, for example, by isolating the bottom of the perforated interval of the well over GNK.

The following is information verifying the method.

So, in Fig.4 shows the change of flow rate with time for the two horizontal wells 29.1 and 29.2, located on one site of the formation of the Eastern bloc of the Orenburg field. Top the perforated interval of the well 29.1 located under STC at a distance of 14.8 m and wells 29.2 above STC 2.4 m Of Fig.1 shows that the flow rate 29.2 higher than wells 29.1, and more stable in the development process. the purpose of the well, plays the role of the internal gas and contributes to the rise of oil.

The results of the process of extracting oil from the Eastern bloc of the Orenburg field system horizontal and inclined wells showed that the volume of oil production from a group of horizontally-inclined wells with the top perforation interval above the STC (SLE 3.1, 3.2, 13.3, 20.1, 29.2) compared with oil production of the group of horizontally-inclined wells with the top perforation interval below the STC to 6 m(SLE. 29.1, 12.1, 13.2, 4.1, 4.3) for the same operating period was 1.7 times higher (table.1).

From what is shown on Fig.5 dependence shows that the distance between the top of the maximum value of oil production is in the area of distances from 0 to 20 M.

If you are developing on the mode of gas repression, i.e. depletion during operation of the reservoir and oil extraction level is decreasing STC. This phenomenon will lead to an increase in gas-liquid factors, and this, in turn, will lead to lower oil production in time. In Fig.6 shows the change of the flow rates of oil and gas-liquid factor (for wells 3.1) years of development. Since 1998-1999 gas-liquid factor began to grow, and the flow rate of oil to fall. Calculations showed that during the tearing perforation on the STC. The change of gas-liquid factor depending on the distance from the STC (for SLE. 3.1) is shown in Fig.7. In Fig.8 shows a plot of flow rate of oil from goodcontrol factor for flowing horizontally-inclined wells of the Eastern block of the Orenburg field (SLE. 3.1, 3.2, 13.3, 14.1, 20.1, 20.2, 30.1, 30.2) from the top of the perforation intervals in the region of the STC. The results showed that the optimal value of oil production lies within the gas-liquid factor 600-700 m3/so In this regard is the periodic measurement of gas-liquid factor, moving the top of the perforated interval is repeated and so on

Examples of specific performance.

Example 1.

As an example, the data on oil production from the Eastern block of the Orenburg field.

The average depth

depth, m 1800-1950

Average net gas pay thickness 25 m

The average saturated thickness of 105 m

Porosity, D. E. 0,08-0,12

The average saturation, D.% 0,75-0,85

Permeability, 10-3μm20,005-0,015

Reservoir temperature, °37

Reservoir pressure, MPa 21,4

Oil viscosity at reservoir conditions, MPa·from 0.44

The oil density at standard conditions, kg/m3836

Pressure us is Efti of two groups of horizontal wells, one of which had a perforation interval above the STC and the other below the STC. From this table it follows that the average flow rate of the first group is 40% higher than the average flow rate of the second group, and the productivity of the first group 44% higher productivity wells of the second group.

Example 2.

As an example, the data on the extraction of oil from oil reservoir u-1 Lokanarkavu field.

Average depth, m 1807

Average net gas pay thickness 6.9 m

The average saturated thickness of 5.6 m

Porosity, D.% 0,16

The average saturation, D. ed 0,63

Permeability, 10-3μm20,0132

Reservoir temperature, °With 98

Reservoir pressure, MPa 31,8

Oil viscosity at reservoir conditions, MPa·0,53

The oil density at standard conditions, kg/m 813

The saturation pressure of oil gas, MPa 30,0

The gas oil, m3/t 250

Table 2 shows data for the extraction and production of oil, liquid, gas-liquid factor horizontal wells at different distances under the STC. From table 2 it follows that the maximum oil output corresponds to the values of gas-liquid factor in the range of 600-700 m3/so

Example 3.

Horizontally-inclined well 19.1, probureny, and the lower perforation interval is located in the region of the STC. This well in 2002, had a rate of 46 t/d., which was above the average rate of other horizontal and inclined wells 16 t/day., which the upper perforation interval was located above the STC in the area from 0 to 20 m, and the bottom below GNK.

As a result, the oil output horizontal and inclined wells increases by 40%, and their productivity is 1.3-1.5 times.

Sources of information

1. Baturin Y. E., Bogdanov, C. L., Degtyaryov E. A., Medvedev N. I., Sarkisyants B. R., George, A. N. The way to develop complex oil with a thin oil rim. RF patent 95116013/03.

2. RF patent №2112868, 10.06.1998 (prototype).

Claims

1. The way to develop low-permeability oil and gas or gascondensate-oil deposits, including transaction deposits in wells with perforations and selection of oil, characterized in that it is held horizontally-inclined wells in podgotovki zone deposits with the location of their top of the perforated interval above the gas-oil contact at a distance of from 0 to 20 m, and the bottom of the perforated interval in podgotovki or oil zone, if this is Russia.

2. The method according to p. 1, characterized in that during the development of deposits on the mode of gas repression produce periodic measurement of gas-liquid factor, above which more than 600-700 m3/t, the upper perforation interval horizontal and inclined wells lowered to achieve this magnitude of gas-liquid factor.

3. The method according to p. 1 or 2, characterized in that the lower perforation interval horizontal and inclined wells have in the field of gas-oil contacts.



 

Same patents:
The invention relates to the oil industry and can find application in the preparation of water for injection into injection wells
The invention relates to the oil industry and can find application in the development of deposits with weak hydrodynamic connection between the wells and the low mobility of oil

The invention relates to the oil and gas industry and can be applied in the development of terrigenous deposits of hydrocarbons, complicated by the presence of zones of different permeability
The invention relates to the oil industry and can be used in the development of oil deposits
The invention relates to the oil industry and can find application in the development of heterogeneous multilayer oil deposits

The invention relates to the field of the oil industry, and in particular to methods of developing multilayer oil fields
The invention relates to the oil industry and can be used in the development of oil deposits, presents a heterogeneous reservoirs using water flooding
The invention relates to the oil industry, in particular to methods for increasing oil recovery from reservoirs with heterogeneous reservoirs by the alignment of the profile injectivity of injection wells and increase coverage of reservoir flooding

The invention relates to the oil industry, in particular to methods of operation of the fields developed using methods of maintaining reservoir pressure, and in particular to methods of injection fluid in the injection well

The invention relates to the oil industry and can find application in the development of complex oil fields

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

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.

1 ex

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.

1 dwg

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

Up!