WO2017193500A1

WO2017193500A1 - Screen pipe used for thickened oil thermal recovery in horizontal well completion

Info

Publication number: WO2017193500A1
Application number: PCT/CN2016/097422
Authority: WO
Inventors: 贺昶明
Original assignee: 四川行之智汇知识产权运营有限公司
Priority date: 2016-05-11
Filing date: 2016-09-28
Publication date: 2017-11-16
Also published as: US20190063196A1; CN105971568A

Abstract

Disclosed is a screen pipe used for thickened oil thermal recovery in a horizontal well completion. The screen pipe comprises a base pipe (4) of which the outer wall is provided with a plurality of oil inlet holes (5). A plurality of reinforcing ribs (3) are axially arranged on the outer circumferential wall of the base pipe (4), and winding wires (2) are circumferentially wound on the plurality of reinforcing ribs (3) at intervals along the base pipe (4). The position between every two adjacent reinforcing ribs (3) is filled with foam iron (8) in a triangular block shape. When the screen pipe is operating, the base pipe (4) is placed on a horizontal segment of a horizontal well completion. Thickened oil enters gaps formed by the winding wires (2) and casing pipes through gaps of the winding wires (2) and enters the interior of the base pipe (4) through the oil inlet holes under the filtering effect of the foam iron (8), so that oil liquid pumping is achieved.

Description

Horizontal completion of heavy oil heat using screen

Technical field

The invention relates to the field of oil exploitation, in particular to the use of a screen tube for the heavy oil heat recovery of a horizontal completion.

Background technique

Petroleum resources exist in naturally occurring reservoirs, and their mining techniques vary with reservoir type and original characteristics. Heavy oil, also known as heavy oil, ie high-viscosity heavy crude oil, refers to heavy crude oil with high viscosity, high density, high content of colloid and asphaltene, ie high-viscosity heavy crude oil, generally containing less wax, so crude oil The viscosity is higher, the flow resistance is larger, and the mining is difficult.

Heavy oil is an important part of petroleum hydrocarbon energy, and its characteristics are as follows:

(1) The colloid and bitumen content in heavy oil is high, and the light fraction is small. Moreover, as the gum and asphaltene content increase, the relative density and viscosity of the heavy oil also increase accordingly.

(2) The viscosity of heavy oil is particularly sensitive to temperature, and the viscosity drops sharply with increasing temperature. And the greater the viscosity of the crude oil, the more obvious this change.

(3) There are many heteroatoms such as sulfur, oxygen and nitrogen in heavy oil.

(4) The paraffin content in heavy oil is generally low, but there are also very few oil fields that are “double high oil fields”, that is, high asphaltene content and high paraffin content, characterized by high viscosity and high freezing point crude oil.

(5) In the same heavy oil reservoir, the nature of crude oil often varies greatly between wells in different vertical oil layers and wells on the plane.

China's heavy oil reserves are abundant, and the annual output of heavy oil accounts for about 10% of the total crude oil production. According to China's second national resource evaluation data, the amount of heavy oil resources is about 8198.710t. However, under the conditions of formation temperature, the viscosity of heavy oil is too high, it is difficult to flow, and it is difficult to produce by conventional oil recovery method. Because of its high viscosity, its mining method is different from that of ordinary crude oil, which is determined by the characteristics of heavy oil. The viscosity of heavy oil is too high, and the fluidity ratio of water is too high, and the use of conventional crude oil mining methods to produce heavy oil is minimal.

At present, the main methods for improving heavy oil recovery in China's major oil fields are steam stimulation. And steam drive, but after steam stimulation and steam drive, the degree of recovery can reach 60%, nearly 40% of heavy oil is not produced after high rounds of throughput and steam drive. After the steam flooding in the heavy oil reservoir, the temperature and pressure of the oil layer changed significantly, and the residual oil saturation between the pores and the residual oil distribution between the wells also changed. However, due to the shallow burial of the oil layer and the loosening of the reservoir, the horizontal well is prone to casing damage, screen damage, packer damage or sand production, which seriously affects the development of horizontal wells.

Summary of the invention

The object of the present invention is to provide a screen for the horizontal completion of heavy oil heat, which is convenient for rapid mining of heavy oil and avoids clogging and damage of the screen.

The object of the invention is achieved by the following technical solution:

The horizontal completion viscous oil heat adopts a screen tube, and includes a base pipe having a plurality of oil inlet holes on the outer wall, and a plurality of reinforcing ribs are arranged on the outer circumferential wall thereof along the axial direction of the base pipe, and the circular direction along the base pipe A plurality of the reinforcing ribs are wound around the winding wire, and the adjacent two reinforcing ribs are filled with foam iron in a triangular block shape. In the working of the invention, the base pipe is placed in the horizontal section of the horizontal completion, and the heavy oil enters into the gap formed between the wire and the sleeve through the wire gap, and after passing through the filtering action of the foam iron, enters the base through the oil inlet hole. Inside the tube to achieve pumping of oil;

In the prior art, steam flooding technology is adopted in the mining of heavy oil, that is, a steam injection well and a production well are arranged above the oil reservoir, and steam is continuously passed through the steam injection well, so that the steam continuously heats the formation around the wellbore while the formation is in the formation. The crude oil is also heated to form a vapor zone that gradually expands with the continuous injection of steam in the formation near the wellbore. The steam can reduce the saturation in the steam zone to a lower degree and will flow the crude oil (ie the original The difference between oil saturation and residual oil saturation drives out the steam zone; at the same time, in the horizontal section of the horizontal completion, the steam moves strongly upwards, while driven by gravity, drives the heated crude oil down. Pour In the opposite direction, as the temperature of the crude oil increases, the mixture of oil and water and gravel in the horizontal section of the horizontal completion will boil, causing the crude oil to be ablated (disturbance caused by the boiling of the mixture), and the mixture of oil, water and solid phase begins to The horizontal completion section enters the inside of the base pipe, and the wire is a complete metal rod and is wound on a plurality of reinforcing ribs by intervals to form a primary filter unit for a large-diameter solid phase such as grit in the oil water, and the foam Iron forms a secondary filtration unit for the small-diameter solid phase to achieve the sand control purpose of the base pipe; and, when the production pressure changes due to the liquid pressure and the heat carried by the oil and water itself in the horizontal section of the horizontal completion, the phase The secondary filtering interval formed between the adjacent two reinforcing ribs is compressed, but in the secondary filtering interval, a plurality of foamed irons in the form of triangular blocks are filled, and the foamed iron is deformed after being subjected to force, and is subjected to secondary filtration. A plurality of flow paths of irregular geometry are still formed in the interval for the oil-water mixture to pass, and the inner hole of the foam iron is slightly changed by the force and is not easily blocked. Iron has a certain elasticity foam, the foam channel reset iron reply elastically deformed to maintain the flow capacity of the secondary filter section, to ensure the smooth extraction of heavy oil.

A plurality of reinforcing ribs are also included, and a plurality of the reinforcing ribs are axially and annularly distributed on the winding wire along the base pipe. In the horizontal section of the horizontal completion, the wire is not only subjected to the pressure of the oil layer, but the pressure changes with the change of the temperature of the oil layer, that is, during the sudden change of the pressure, the wire is extremely vulnerable, and the present invention passes A plurality of annularly distributed reinforcing ribs are arranged on the wire so that the primary filtering unit formed by the winding wire is stably supported to cope with the ever-changing production pressure in the horizontal section of the horizontal completion and to prolong its own service life.

A TiALN-WC/C layer is coated on the outer wall of the wire. Preferably, the TiALN-WC/C coating is provided on the outer wall of the wire, and the friction coefficient of the TiALN-WC/C coating is only 0.1. When the solid phase such as sand is continuously contacted with the wire, the relationship between the two can be greatly reduced. Friction loss, And with self-lubricating, greatly guarantee the service life of the winding wire in the horizontal completion.

The connector further includes a connector, and the two ends of the base pipe are respectively connected to the blind pipe through the connector. Preferably, according to the needs of actual oil recovery, the base pipe is connected to the blind pipe through the joint head to facilitate the pumping of the crude oil, and the conventional blind pipe and the base pipe are directly welded in the laying process, so as to facilitate direct damage to the wire wound Replacing the wire without replacing the base pipe and the wire as a whole, reducing the production cost of heavy oil mining.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The present invention compresses the secondary filtration interval formed between two adjacent reinforcing ribs when the production pressure changes due to the liquid pressure and the heat carried by the oil and water itself in the horizontal completion section, but the secondary filtration interval formed between the adjacent two reinforcing ribs is compressed, but The secondary filtration section is filled with a plurality of foamed irons in the form of triangular blocks. After the deformation of the foamed iron, a plurality of flow paths of irregular geometry are formed in the secondary filtration interval for the oil-water mixture to pass through. And the foamed iron inner hole is slightly changed by the force and is not easily blocked. At the same time, the foamed iron has a certain elasticity, and the pores in the foamed iron are reset when the elastic deformation is restored, so as to maintain the seepage ability in the secondary filtration interval, and ensure Smooth mining of heavy oil;

2. When the production pressure changes due to the pressure of the liquid and the heat carried by the oil and water itself in the horizontal section of the horizontal completion, the secondary filtration interval formed between the adjacent two reinforcing ribs is compressed, but The secondary filtration section is filled with a plurality of foamed irons in the form of triangular blocks. After the deformation of the foamed iron, a plurality of flow paths of irregular geometry are formed in the secondary filtration interval for the oil-water mixture to pass through. And the foamed iron inner hole is slightly changed by the force and is not easily blocked. At the same time, the foamed iron has a certain elasticity, and the pores in the foamed iron are reset when the elastic deformation is restored, so as to maintain the seepage ability in the secondary filtration interval, and ensure Smooth mining of heavy oil;

3. The present invention provides a TiALN-WC/C coating on the outer wall of the wire, and TiALN-WC/C The coefficient of friction of the coating is only 0.1. When the solid phase such as sand is continuously in contact with the wire, the friction loss between the two can be greatly reduced, and the self-lubricating property is provided to ensure the service life of the wire in the horizontal completion. .

DRAWINGS

The drawings are intended to provide a further understanding of the embodiments of the present invention, and are not intended to limit the embodiments of the invention. In the drawing:

Figure 1 is a schematic structural view of the present invention;

Figure 2 is a longitudinal cross-sectional view of the present invention.

Marked in the drawing and the corresponding part name:

1-ribs, 2-wound wire, 3-strength rib, 4-base tube, 5-inlet hole, 6-joint head, 7-blind tube, 8-foam iron.

detailed description

The present invention will be further described in detail below with reference to the embodiments and the accompanying drawings. As a limitation of the invention.

Example 1

As shown in FIG. 1 to FIG. 2, the embodiment includes a base pipe 4 having a plurality of oil inlet holes 5 formed in the outer wall, and a plurality of reinforcing ribs 3 are disposed on the outer circumferential wall thereof along the axial direction of the base pipe 4, And the winding wire 2 is wound around the plurality of reinforcing ribs 3 along the circular direction of the base pipe 4, and the adjacent two reinforcing ribs 3 are filled with foam iron 8 in the shape of a triangular block. In the working of the invention, the base pipe 4 is placed in the horizontal section of the horizontal completion, and the heavy oil enters into the gap formed between the wire 2 and the casing through the gap of the wire 2, and passes through the filtering after the foaming iron 8 is filtered. The hole 5 enters the inside of the base pipe 4 to realize pumping of the oil;

In the prior art, steam flooding technology is used in the mining of heavy oil, that is, in the oil reservoir. The steam chamber and the production well are set up, and the steam is continuously passed through the steam injection well, so that the steam continuously heats the formation around the wellbore, and the crude oil in the formation is also heated, and the formation in the formation near the wellbore gradually expands with the continuous injection of steam. a steam zone that reduces the saturation of the steam zone to a lower degree and drives the flowable crude oil (ie, the difference between the original oil saturation and the residual oil saturation) out of the steam zone; at the same time, In the horizontal section of the horizontal completion, the steam moves strongly upwards, and under gravity drive, the heated crude oil is driven downwards, and as the temperature of the crude oil increases, the oil and water in the horizontal section of the horizontal completion And the mixture of gravel and other materials will boil, causing the crude oil to be ablated (disturbance caused by the boiling of the mixture), and the mixture of oil, water and solid phase begins to enter the inside of the base pipe 4 from the horizontal completion level, and the wire 2 is a complete The metal rod is wound on the plurality of reinforcing ribs 3 by intervals to form a primary filter unit for a large diameter solid phase such as grit in oil water, and the foamed iron 8 forms a solid phase for the small diameter. Filtering unit to achieve the sand control purpose of the base pipe 4; and, when the production pressure changes due to the liquid pressure and the heat carried by the oil and water itself in the horizontal section of the horizontal completion, the adjacent two reinforcing ribs 3 are formed. The secondary filtration interval is compressed, but the secondary filtration interval is filled with a plurality of foamed irons 8 in the form of triangular blocks, and the foamed iron 8 is still formed in the secondary filtration interval after the force is deformed. The flow path of the irregular geometry is passed by the oil-water mixture, and the inner hole of the foamed iron 8 is slightly changed by the force and is not easily blocked, and the foamed iron 8 has a certain elasticity, and the foamed iron 8 is restored when the elastic deformation is restored. The pores are reset to maintain the seepage capacity in the secondary filtration zone to ensure the smooth mining of heavy oil.

The embodiment further includes a plurality of reinforcing ribs 1 , and a plurality of the reinforcing ribs 1 are axially and annularly distributed on the winding wire 2 along the base pipe 4 . In the horizontal section of the horizontal completion, the wire 2 is not only Under the pressure of the oil layer, and the pressure changes with the change of the temperature of the oil layer, that is, the winding wire 2 is extremely vulnerable during the sudden change of the pressure, and the present invention provides a plurality of annular distributions on the winding wire 2. The rib 1 is such that the primary filter unit formed by the wire 2 is stably supported to cope with the ever-changing production pressure in the horizontal section of the horizontal completion while prolonging its own service life.

Preferably, the TiALN-WC/C coating is provided on the outer wall of the wound wire 2, and the friction coefficient of the TiALN-WC/C coating is only 0.1, which can greatly reduce both when the solid phase such as sand is continuously contacted with the wound wire 2. The friction loss between the two, and with self-lubricating, greatly guarantees the service life of the wound wire 2 in the horizontal completion.

Preferably, according to the actual oil recovery requirement, the base pipe 4 is connected to the blind pipe 7 through the joint head 6 to facilitate the pumping of the crude oil, and the conventional blind pipe 7 and the base pipe 4 are directly welded at the time of laying, so as to facilitate When the wire 2 is damaged, the wire 2 is directly replaced without replacing the base pipe 4 and the wire 2 as a whole, thereby reducing the production cost of heavy oil mining.

The specific embodiments of the present invention have been described in detail with reference to the preferred embodiments of the present invention. All modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

The horizontal completion viscous oil heat adopts a screen tube, and includes a base pipe (4) having a plurality of oil inlet holes (5) on the outer wall, characterized in that: along the axial direction of the base pipe (4), on the outer circumferential wall thereof a plurality of reinforcing ribs (3) are disposed, and a winding wire (2) is wound on the plurality of reinforcing ribs (3) along the circular direction of the base pipe (4), and two adjacent reinforcing ribs (3) are arranged Filled with foamed iron (8) in the form of a triangular block.
The horizontal completion heavy oil heat-consuming screen according to claim 1, characterized in that it further comprises a plurality of reinforcing ribs (1) along which the plurality of reinforcing ribs (1) are axially And distributed in a ring shape on the wire (2).
The horizontal completion heavy oil heat according to claim 1 adopts a sieve tube, characterized in that the outer wall of the wound wire (2) is coated with a TiALN-WC/C layer.
The horizontal completion heavy oil heat-consuming screen according to claim 1, characterized in that it further comprises a joint (6), the two ends of the base pipe (4) respectively passing through the joint (6) and the blind pipe ( 7) Connect.