RU2243374C1 - Method for extraction of oil deposit - Google Patents

Abstract

FIELD: oil and gas extractive industry.

SUBSTANCE: method includes mounting debit meters above each productive bed with local power source connected to electronic counter with memory block, before lowering pump into well. If necessary debit meters are raised to surface and oil extraction from each layer is determined. Dependently on debit meters indications if detecting a substantial decrease of oil yield from any bed treatment of face-adjacent area of this bed sis performed and mode of forcing working agent into non-satisfactory bed is changed.

EFFECT: higher efficiency.

2 cl, 2 dwg

Description

The invention relates to the oil industry and can be used in the development of multi-layer oil deposits.

A known method of developing oil deposits, including the selection of oil through production wells from the reservoirs, the selection of produced water from the aquifer through the water wells and injection of produced water through the injection wells into the formation, looping of flow lines of the water wells, redistributing the volumes of injection of formation water by studying the supply pipelines to the injection pipes wells, and when one or more water wells are stopped, formation water is extracted from other water wells and injection into injection wells through a looped pipe and choked pipelines leading to injection wells, while providing injection of formation water with electric centrifugal pumps with a total capacity, somewhat lower total injectivity of injection wells, and by looping and plating provide redistribution and limitation of pumped volumes of the working agent to the level of electric centrifugal performance pumps (RF Patent 2177537, cl. E 21 B 43/20, 2001).

The disadvantage of this method is the low efficiency of the selection with a decrease in reservoir pressure, as well as the lack of information about the flow rate of wells necessary to control the technological process of selection.

There is also known a method of developing oil deposits, including

the selection of oil from the reservoir through production wells using pumping units and the injection of a working agent through injection wells (Lysenko VD Oil field development: Theory and practice. - M .: Nedra, 1996. - S. 280-287).

The disadvantage of this method is the low efficiency of controlling the technological process of oil selection from several productive formations through one well, due to the lack of incomplete information about the flow rate of individual formations.

The objective of the present invention is that it is necessary to create such a method of developing an oil reservoir, which would provide the maximum possible control of the technological process of oil selection from several reservoirs through one well.

The technical result consists in increasing the efficiency of controlling the technological process of extracting oil from several reservoirs through one well (based on data on the selection of oil from each reservoir of a multilayer reservoir through one well and making a decision on processing the bottom-hole formation zone (BFZ) or changing the operating mode of the pressure injectors wells.

The specified technical result in the implementation of the claimed invention is achieved by the described method according to the prototype, including the selection of oil from the reservoir through production wells using pumping units and pumping the working agent through injection wells, the new is that while the selection of oil through one well from several reservoirs before the pump unit is launched into the well, the deep flow meters are sequentially lowered and installed on packers in the inter-reservoir space in Above each controlled formation, the number of flowmeters is equal to the number of productive layers, with each flowmeter equipped with an autonomous power source and an electronic meter connected to it with a memory unit, then, depending on the readings of the flow meters, the bottom-hole zone of this formation is processed with a decrease in oil withdrawal from a formation. and change the mode of injection of the working agent into an unsatisfactory working formation.

The volume taken from each oil reservoir for a fixed period of time is determined after the rise of the flowmeters to the surface according to the formula:

Q _i = Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i}}$ -Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i-1}}$ ,

where Q _i is the flow rate of the i-th layer, m ³ / day;

Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i}}$ and Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i-1}}$ - readings of flow meters located respectively above and below the i-th layer, m ³ / day.

Depending on the readings of the flow meters, the bottom-hole zone of the formations is cleaned and the mode of injection of the working agent into the formations is changed.

If there is a total flow rate meter on the surface, the upper dibitometer can not be lowered into the well.

Figure 1 presents a diagram of an implementation of a method for developing an oil reservoir.

Figure 2 - presents a General view of the flow meter.

The implementation scheme includes a pump unit 1, installed under the tubing 2, flow meters 3, 4 and 5, installed respectively using packers 6, 7 and 8 in the casing 9 above the reservoir 10, 11 and 12. Casing 9 at the level of reservoirs 10, 11 and 12 has perforation zones 13, 14 and 15.

As the flow meters 3, 4 and 5, for example, rotary flow meters (FIG. 2) can be used, comprising an impeller 16 connected through a magnetic coupling 17 and an inductive speed sensor 18 of the impeller with an electronic counter with a memory unit 19 made in the form of a microprocessor. The flow meters 3, 4 and 5 are also equipped with an electronic clock 20 and an autonomous power source 21 connected to an electronic meter 19 and an electronic clock 20. All elements of the flow meters 3, 4 and 5 (except the impeller 12) are installed in a sealed housing 22.

The method implements as follows. Before the descent of the pumping unit 1, the flow meters 3, 4, and 5 are sequentially lowered into the well, which are installed using packers 6, 7, and 8. The flow meters 3, 4, and 5 are installed in the interstratal space above the controlled productive formations 10, 11, and 12. After the descent and when the pump unit 1 is switched on, the oil flow from the strata 10, 11 and 12 enters through the perforation zones 13, 14 and 15 into the casing 9, from where, bypassing the flowmeters 3, 4 and 5, to the input of the pump unit 1 and further along the tubing to the surface. Under the influence of the fluid flow, the impellers 16 begin to rotate. This rotation is transmitted through a magnetic clutch 17 to the transformer 18 of the number of revolutions into electrical pulses, which are recorded by an electronic meter with a memory unit 19. The electronic clock 20 records the time of the counters 19. The ratio of the number of pulses to the time of their accumulation is proportional to the flow rate of oil from the reservoir. Moreover, the flow rate of the reservoir 10 is equal to the readings of the flow meter 3, the flow rate of the reservoir 11 is equal to the difference between the readings of the flowmeters 4 and 3, and the flow rate of the reservoir 12 is equal to the difference of the readings of the flowmeters 5 and 4.

With a significant reduction in the total flow rate measured on the surface, for example, using the “Sputnik” measuring device (not shown in the drawing), or during the repair of the pump installation, flowmeters are extracted to the surface, after processing (interpretation) of these flowmeters, the average oil flow rate for the control period is determined each layer. If there is a total flow meter measured on the surface, the upper flow meter can not be lowered into the well.

If a significant decrease in oil withdrawal from any formation is detected, the bottom-hole zone of this formation is processed and the injection mode of the working agent is changed into an unsatisfactory working formation.

Thus, monitoring the selection of oil from each reservoir of a multilayer reservoir and making, based on the information received, an informed decision on processing the bottomhole formation zone and pumping the working agent into injection wells will increase the efficiency of oil field development.

Claims (2)

1. The method of developing an oil reservoir, including the selection of oil from the reservoir through production wells using pumping units and pumping the working agent through injection wells, characterized in that while simultaneously taking oil through one well from several reservoirs before the pumping unit is launched into the well in series lower depth flow meters and install them on packers in the inter-reservoir space above each controlled formation, the number of flow meters is equal to the number of productive reservoirs, and each flow meter is equipped with an independent power source and an electronic meter connected to it with a memory unit, then, depending on the flow meter readings, when the oil withdrawal from a reservoir is reduced, the bottom-hole zone of this reservoir is processed and the operating agent injection mode is changed to an unsatisfactory one layer. 2. The method according to claim 1, characterized in that the volume of oil selected from each formation for a fixed period of time is determined after lifting the flowmeters to the surface according to the formula: Q _i = Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i}}$ -Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i-1}}$ , where Q _i is the flow rate of the i-th layer, m ³ / day; Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i}}$ - readings of a flow meter located above the i-th layer, m ³ / day; Q $\genfrac{}{}{0ex}{}{\text{d}}{\text{i-1}}$ - readings of a flow meter located below the i-th layer, m ³ / day.

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