RU2224883C2 - Method for impulsive treatment of productive layers and filters - Google Patents

Abstract

FIELD: oil extracting industry. SUBSTANCE: method includes pumping of working agent through pipe column in the well. The flow is converted into impulsive flow and mechanical vibrator oscillations. Vibrator consists of generator of fluid pressure oscillations in form of a venturi with inlet nozzle and diffuser, operating in mode of periodical leaf cavitation, stem and outlet device. Space behind pipe column above the productive layer is separated by a packer. Above the packer jet pump is mounted. Part of working agent is fed into the jet pump from pipe column for outletting fluid from area below packer and injecting fluid into area above packer. Speed of outletting fluid from below the packer is kept equal or greater than speed of working agent passing through vibrator into the well and is also kept greater than sum of working agent speed and productive layer flow speed. EFFECT: increased effectiveness of treatment of productive layers and filters. 3 dwg

Description

The proposals relate to pulsed processing of reservoirs and well filters.

Known operating in the periodic intermittent cavitation mode are oscillators of fluid pressure in the form of a venturi with an inlet nozzle and diffuser [1].

A known method of pulsed processing of productive reservoirs and well filters by pumping a working agent stream through a pipe string located in the well and converting said stream into a pulse stream and mechanical vibrations of a vibrator, consisting of a fluid pressure fluctuation generator in the form of a Venturi tube operating in periodically discontinuous cavitation mode input nozzle and diffuser, barrel and output device [2, 3]. However, the known method has the following disadvantages. With a deep arrangement of productive formations, a large backpressure is created, mainly determined by static pressure. The latter, in addition to reservoir pressure, is also determined by the flow of fluid into the well through a vibrator.

At the same time, a vibrator with a cavitation generator in the form of a Venturi tube generates fluid pressure fluctuations at the ratio of backpressure at the outlet to the pressure at the inlet of the vibrator in the range of 0.05-0.7. In this case, the optimal mode (maximum amplitude of pressure fluctuations) takes place at the indicated pressure ratio in the range of 0.2-0.35, which is not always possible due to the high back pressure.

The proposed technical solution is aimed at increasing the efficiency of treatment of productive reservoirs and well filters by ensuring the operation of vibrators in the optimal mode of periodically stall cavitation and the generation of pulses of maximum amplitude while reducing static pressure on the reservoir.

This result is achieved due to the fact that in the method of pulsed processing of productive reservoirs and well filters by supplying a working agent stream through a pipe string located in the well and converting said stream into a pulsed flow and mechanical vibrations of a vibrator, consisting of a vibration generator operating in periodically discontinuous cavitation mode fluid pressure in the form of a venturi with an inlet nozzle and diffuser, a barrel and an outlet device, divide the annular space of the well above productively of the first reservoir, a jet pump is installed above the packer and part of the working agent is fed into it from the pipe string to ensure ejection from the sub-packer zone and injection into the over-packer zone, while providing an ejection rate higher than the rate of fluid entry into the well through the vibrator, and also due to that determine the flow rate of the productive formation before processing, and the ejection rate from the sub-packer zone is equal to or greater than the sum of the flow rate entering the well from the vibrator and flow rate p reservoir.

The invention is illustrated by drawings, where in Fig.1 shows a schematic diagram of the processing of a reservoir or filter, in Fig.2 - a vibrator, and in Fig.3 - a jet pump.

A vibrator 2 is connected to the pipe string 1 located in the well and includes a venturi 3 with an inlet nozzle 4 and a diffuser 5, a barrel 6 and an output device 7. The annulus 8 above the reservoir 9 is divided by the packer 10 into the subpacker 11 and overpacker 12 zones. Above the packer set the jet pump 13.

From the inner cavity of the pipe string 1, a part of the working agent is sent to the jet pump 13 through the channel 14, its low-pressure zone 15 is connected by a pipe 16 to the sub-packer zone 11 of the annulus, providing ejection of the liquid from it and its injection together with the working agent entering the jet pump 13 through the channel 17 to the overpacker zone 12 and its transportation to the wellhead.

Due to this, a backpressure is achieved that does not exceed the reservoir pressure, for which they ensure that the rate of ejection of the liquid is equal to the rate of entry of the working agent into the well through the vibrator 2.

For a depressing effect on the formation, the flow rate is determined before the start of treatment and, during processing, an ejection rate is provided that exceeds the sum of the rate of the working agent entering the well through the vibrator and the flow rate of the formation.

Thus, this technical solution will allow:

to increase the efficiency of processing productive formations and well filters by ensuring the vibrator operates in optimal conditions with a maximum amplitude of fluid pressure fluctuations;

accelerate the process of processing the reservoir by reducing reservoir pressure in the well.

Sources of information

1. Pilipenko V.V. Cavitation self-oscillations. - Kiev: Naukova Dumka, 1989.

2. Melamed Yu.A. Hydropulse technology: great opportunities and a wide range of applications. "Exploration and protection of the subsoil." - M .: Nedra, 1993, 6, p. 19.

3. RF patent No. 2070286, MKI E 21 V 43/26, 97.

Claims (1)

The method of pulsed processing of reservoirs and filters by supplying a working agent stream through a pipe string located in the well and converting said stream into a pulsed stream and mechanical vibrations of a vibrator consisting of a fluid pressure oscillation generator in the form of a Venturi tube with an inlet nozzle and periodically intermittent cavitation diffuser, barrel and output device, characterized in that they divide the annular space of the well above the reservoir with a packer, above which is installed the jet pump is poured and part of the working agent is fed into it from the pipe string to ensure fluid ejection from the sub-packer zone and injection into the super-packer zone, while providing a fluid ejection rate from the sub-packer zone equal to or greater than the velocity of the working agent into the well through a vibrator, or exceeding the sum of the speeds of the working agent and the flow from the reservoir.

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