RU2176336C1 - Method for operation of pump-ejector well unit - Google Patents

Abstract

FIELD: jet equipment. SUBSTANCE: first a blocking insert with a through relief conduit is installed in the passing conduit, and the intake conduits to the jet pump of the working and ejected media get cut off by means of this insert. Then chemical reagents get injected in the well through the string of pump-compressor pipes and the packer is unpacked, after that backpressure is built up in the hole clearance above the packer by means of the pump unit, which does not exceed the pressure test pressure of the casing string, and chemical reagents and buffer liquid are forced through in the seam. Then the blocking insert is replaced with a depression insert, and after that the working medium is fed through the string of the pump-compressor pipes to the nozzle of the working medium jet pump, and an adjustable pressure is built up due to it in the zone under the packer for drainage of the seam and other preventive maintenance operations. EFFECT: enhanced efficiency of the well face zone. 3 dwg

Description

 The invention relates to the field of inkjet technology, mainly to downhole jet units for processing bottom-hole formation zone.

 A known method of operating a downhole jet installation, comprising supplying a working medium through a string of tubing to a nozzle of a jet pump, dragging an ejected medium with it, and supplying a mixture of media from the well to the surface (see US Pat. No. 4,744,730, published in 1986).

 However, in this method of operation there is no possibility of affecting the bottom-hole zone, which narrows the possibilities of using a plant using this method of operation.

 The closest to the invention in technical essence and the achieved result is a method of operating a pump-ejector well installation, comprising installing a jet pump in a well on a string of tubing installed in a housing with a channel made in the last passage, pumping into a formation along the tubing string pipes of chemical reagents, followed by pumping from the formation of reaction products (see patent RU 1668646, publ. 07.08.1991).

 However, the use of this method of operation is limited, due to the fact that in some cases the packer cannot ensure the tightness of separation of the annulus of the well, which reduces the efficiency of processing the bottom-hole zone of the well.

 The problem to which the present invention is directed, is to increase the efficiency of processing the bottom-hole zone of the well.

 This problem is solved due to the fact that the method of operation of a pump-ejector well installation includes installing a jet pump in a well on a tubing string located in a housing with a channel made in the last passage, and injecting chemical reagents into the reservoir along the tubing string followed by pumping reaction products out of the formation, and at the same time, first, a blocking insert with a through-flow channel is installed in the passage channel of the jet pump housing, and through this insert, They open the channels for supplying the working and ejected media to the jet pump, then pump the tubing into the well through the tubing string and through the bypass channel of the chemical blocking insert and unpack the packer, after which counterpressure is created in the annulus above the packer using an additional pump unit, not exceeding the pressure of crimping the casing and pushing into the reservoir with the help of the main pumping unit chemicals and buffer fluid, and then blocking the replacement insert is replaced by a depression insert, whereby the tubing string above the depression is communicated with the fluid supply path to the jet pump nozzle and the tubing string below the depression is communicated with the fluid injection path to the jet pump, and then supply along the string of tubing into the nozzle of the jet pump of the working medium and thereby create an adjustable pressure in the subpacker zone with the possibility of drainage and other routine maintenance.

 During routine maintenance in the well, for example, to increase the injectivity of injection wells or to increase the productivity of production wells introduced after drilling and overhaul, conditions arise when the packer cannot provide tightness when crushing chemicals or grouting materials into the formation during waterproofing operations. As a result, there is a risk of packer breakdown and, as a result, low efficiency of the work performed.

 The above-described sequence of operations for conducting chemical treatment of the bottom-hole zone of the well in dynamic mode or other work associated with crushing special solutions into the reservoir allows avoiding packer breakdown and increasing the efficiency of the treatment, which is due to the fact that before the bursting of chemical reagents and buffer fluid, increase in pressure in the annular sup packer space of the well. As a result, the pressure drop across the packer sharply decreases, which allows for the forcing of chemical reagents at a pressure increased by the amount of back pressure, which is close to the value of the pressure of the casing of the borehole casing.

 As a result, the achievement of the objective of the invention is achieved - improving the reliability of the work while increasing the productivity of the wells put into operation or improving the quality of waterproofing works.

 In FIG. 1 shows a section of a pumping-ejector well installation with a blocking insert at the time of injection of chemicals; in FIG. 2 - section of the installation at the time of forcing the chemical reagent and buffer fluid; in FIG. 3 is a sectional view of an installation with a depressed insert installed.

 The pump-ejector well installation comprises a housing 2 installed in the well on the tubing 1 with a passage channel 3 formed therein and a jet pump 4 installed in the housing 2 with a channel 5 for supplying a working medium to the nozzle 6 and a channel 7 for supplying an ejected medium. In the passage channel 3, a blocking insert 8 with a through passage channel 9 with overlapping channels 5 and 7 of the supply of working and ejected media is installed with the possibility of replacement. When replacing the blocking insert 8, a depression insert 10 is installed in its place. Below the casing 2, a packer 11 is installed on the tubing 1.

 The method of operation of the pump-ejector installation is implemented as follows.

 In the well, a jet pump 4 is installed on the tubing string 1, the latter being placed in the housing 2 in which the passage channel 3 is made. Packer 11 installed on the tubing string 1 is in an unpacked state (Fig. 1). First, in the passage channel 3 of the housing 2, a blocking insert 8 is installed with a through-passage channel 9, and by means of this insert 8, the channels 5 and 7 for supplying the working and ejected media to the jet pump 4 are closed. This prevents chemicals from entering both the jet pump 4 and the annular over-packer space. Then, injection into the well is carried out through the tubing string 1 and through the bypass channel 9 of the blocking insert 8 of chemical reagents. After that, unpacking the packer 11 (Fig. 2). In the annular nadpakerny space using an additional pump unit create a back pressure that does not exceed the pressure of the casing string 12, and push the chemical reagents and buffer fluid into the formation. Then, the blocking insert 8 is replaced by a depression insert 10 (Fig. 3), by means of which the tubing string 1 above the depression insert 10 is communicated with the medium supply channel 5 to the nozzle 6 of the jet pump 4 and the tubing string 1 below the depression 10 communicate with the channel 7 for supplying the ejected medium to the jet pump 4. Using the main pumping unit, the working medium is supplied through the tubing string 1 to the nozzle 6 of the jet pump 4. The working medium, flowing out of the nozzle 6, pumps out from the borehole zone below the packer 11 reaction products formed as a result of interaction with a chemical reagent. As a result, an adjustable pressure required by the technological regulations is created in the sub-packer zone with the possibility of draining the formation and other routine maintenance.

 The present invention can be used in the oil industry when conducting work to increase the productivity of oil and gas wells and waterproofing works.

Claims (1)

 The method of operation of a pump-ejector well installation, including installing a jet pump in a well on a tubing string located in a housing with a channel made in the last passage, injecting chemical reagents into the formation along the tubing string, followed by pumping reaction products from the formation, characterized in that at first a blocking insert with a through-passage channel is installed in the passage channel, and by means of this insert the supply channels to the jet pump and cased media, then they pump into the well through the tubing string and through the bypass channel of the chemical blocking insert and unpack the packer, then create backpressure in the annular over-packer space using the pump unit, which does not exceed the pressure of the casing pressure, and push it into formation chemicals and buffer fluid, and then the blocking insert is replaced by a depression insert, through which the tubing string above the dep the spring insert is communicated with the channel for supplying the working medium to the nozzle of the jet pump and the tubing string below the depression insert is communicated with the channel for supplying the ejected medium in the jet pump and then feed the tubing to the nozzle of the jet pump of the working medium and create due to this, in the sub-packer zone, adjustable pressure with the possibility of conducting drainage of the formation and other routine maintenance.

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