阅读说明：本技术 利用环空结构的定向井多重防砂方法 (Multiple sand prevention method for directional well by utilizing annular structure ) 是由 李中 范白涛 于继飞 闫新江 李占东 张海翔 黄辉 幸雪松 张磊 张海龙 文敏 于 2021-08-24 设计创作，主要内容包括：本发明涉及一种利用环空结构的定向井多重防砂方法,包括：对油井水平油层出砂粒径发生改变的区域进行预测、查验油井综合出砂量与粒径分布；基于油井综合出砂量与粒径分布,将油井水平油层出砂粒径发生改变的区域划分为若干出砂井段；调配防砂材料,在油井出砂前端油管与套筒之间的环形空腔中注入防砂材料；在所述防砂材料的上方下入封隔器进行固定、封隔；下入井深探测器查看所述防砂材料与所述封隔器是否达到预计位置、长度与效果；注入所述防砂材料,再下入所述封隔器,依次类推,直至若干所述出砂井段被填充满。该方案实施后油井可以起到有效防砂能力的同时又保证了液相油流的通过。(The invention relates to a multiple sand control method for a directional well by utilizing an annular structure, which comprises the following steps: predicting and checking the comprehensive sand production amount and particle size distribution of the oil well in the area with changed sand production particle size of the horizontal oil layer of the oil well; dividing a region with changed sand production particle size of a horizontal oil layer of the oil well into a plurality of sand production well sections based on the comprehensive sand production amount and particle size distribution of the oil well; preparing a sand control material, and injecting the sand control material into an annular cavity between an oil pipe at the sand production front end of an oil well and a sleeve; setting a packer above the sand control material for fixing and packing; a well-entering depth detector checks whether the sand control material and the packer reach the expected position, length and effect; and injecting the sand control material, then putting the packer, and the like until the sand outlet well sections are filled. After the scheme is implemented, the oil well can play the effective sand prevention capacity and simultaneously ensure the passing of liquid-phase oil flow.)

1. A multiple sand control method for a directional well by utilizing an annular structure is characterized by comprising the following steps:

predicting and checking the comprehensive sand production amount and particle size distribution of the oil well in the area with changed sand production particle size of the horizontal oil layer of the oil well;

dividing a region with changed sand production particle size of a horizontal oil layer of the oil well into a plurality of sand production well sections based on the comprehensive sand production amount and particle size distribution of the oil well;

preparing a sand control material, and injecting the sand control material into an annular cavity between an oil pipe (3) at the sand production front end of the oil well and the sleeve (2);

setting a packer above the sand control material for fixing and packing;

a well-entering depth detector checks whether the sand control material and the packer reach the expected position, length and effect;

and injecting the sand control material, then putting the packer, and the like until the sand outlet well sections are filled.

2. The multiple sand control method for the directional well according to claim 1, characterized in that the specific processes of predicting the area with changed sand production particle size of the horizontal oil reservoir of the oil well and checking the comprehensive sand production amount and particle size distribution of the oil well are as follows:

analyzing the sand grain size, the sand yield and the sand yield area of the oil well rock sample, predicting the sand content after the oil flow flows out in the later period of the oil well, predicting the area with changed sand grain size of the horizontal oil layer of the oil well after the sand content, the sand grain diameter and the sand yield area of the directional well are found to be changed, and checking the comprehensive sand yield and the grain size distribution of the oil well.

3. The multiple sand control method for the directional well according to the claim 1, wherein the sand control material is composed of quartz sand, ceramic particles, coating sand, chemical sand control agent and sand control curing agent.

4. The multiple sand control method for the directional well according to claim 3, wherein the mass ratio of the quartz sand or the ceramsite to the coating sand to the chemical sand control agent to the sand control curing agent is 90: 10: 20: 25.

5. the multiple sand control method for a directional well according to claim 4, wherein the sand control material comprises a first section of sand control material (601), a second section of sand control material (602), a third section of sand control material (603), a fourth section of sand control material (604) … …, and a nth section of sand control material.

6. The multiple sand control method for directional wells according to claim 5, wherein the first section of sand control material (601), the second section of sand control material (602), the third section of sand control material (603), the fourth section of sand control material (604) … … have different particle sizes of quartz sand in the Nth section of sand control material.

7. The multiple sand control method for a directional well according to claim 3, wherein the chemical sand control agent comprises a modified epoxy resin glue, an unsaturated resin and a furan resin.

8. The multiple sand control method for the directional well according to claim 3, wherein the sand control curing agent comprises a water-soluble curing agent and an oil-soluble curing agent, and the proportion of the water-soluble curing agent to the oil-soluble curing agent is 7: 3; the water-soluble curing agent comprises glycerol, phenol or acetone; the oil-soluble curing agent comprises a low molecular weight polyamide.

Technical Field

The invention relates to a multiple sand control method for a directional well by utilizing an annular structure, belonging to the field of sand control processes of oil wells.

Background

The loose sandstone reservoir is serious in sand production in heavy oil exploitation in China, the main sand production reason is poor cementation, and the high viscosity of crude oil drives sediment to generate blockage on a shaft of an oil well after the sediment is moved, so that the yield of the oil well is seriously influenced. In the existing heavy oil production technology, the screen pipe and the artificial well wall are used as sand control ways in the early and middle stages, and in the chemical sand control process, chemical agents can influence the physical properties of the stratum and pollute the stratum. When the heavy oil well is exploited to the later stage, the sand grain size of the oil deposit is changed, and partial gravel enters the bottom of the oil well through the artificial well wall and then enters the oil pipe to cause the yield of the oil well to slide down. And, along with the development, the sand production region, the sand production type also can change, and to the sand production degree and the particle size in different regions be present problem, current sand control technology can't effectively reach the sand control purpose.

Disclosure of Invention

The invention provides a multiple sand control method for a directional well by utilizing an annular structure, which divides a sand production oil layer into different areas according to different sand production degrees at the later stage of oil layer exploitation, after the different areas are sealed by using packers, sand control materials with different levels are additionally arranged in the annular area between an oil pipe and a casing pipe, so that the purpose of triple sand control is achieved together with a screen pipe and an artificial well wall, the sand control effect is improved to the maximum extent, and the oil layer is not greatly influenced and polluted.

In order to achieve the purpose, the invention adopts the following technical scheme:

a multiple sand control method for a directional well using an annulus structure, comprising:

predicting and checking the comprehensive sand production amount and particle size distribution of the oil well in the area with changed sand production particle size of the horizontal oil layer of the oil well;

dividing a region with changed sand production particle size of a horizontal oil layer of the oil well into a plurality of sand production well sections based on the comprehensive sand production amount and particle size distribution of the oil well;

preparing a sand control material, and injecting the sand control material into an annular cavity between an oil pipe at the sand production front end of an oil well and a sleeve;

setting a packer above the sand control material for fixing and packing;

a well-entering depth detector checks whether the sand control material and the packer reach the expected position, length and effect;

and injecting the sand control material, then putting the packer, and the like until the sand outlet well sections are filled.

The multiple sand control method for the directional well preferably comprises the following specific processes of predicting and checking the region with changed sand production particle size of the horizontal oil reservoir of the oil well, wherein the specific processes comprise the following steps:

analyzing the sand grain size, the sand yield and the sand yield area of the oil well rock sample, predicting the sand content after the oil flow flows out in the later period of the oil well, predicting the area with changed sand grain size of the horizontal oil layer of the oil well after the sand content, the sand grain diameter and the sand yield area of the directional well are found to be changed, and checking the comprehensive sand yield and the grain size distribution of the oil well.

According to the multiple sand control method for the directional well, preferably, the sand control material is composed of quartz sand, ceramsite, coating sand, a chemical sand control agent and a sand control curing agent.

Preferably, the mass ratio of the quartz sand (or ceramsite), the coating sand, the chemical sand control agent and the sand control curing agent is 90: 10: 20: 25.

preferably, the sand control materials comprise a first section of sand control material, a second section of sand control material, a third section of sand control material and a fourth section of sand control material … … section N sand control material.

In the multiple sand control method for the directional well, preferably, the particle sizes of the quartz sand in the first section of sand control material, the second section of sand control material, the third section of sand control material and the fourth section of sand control material … … are different.

Preferably, the chemical sand control agent comprises modified epoxy resin glue, unsaturated resin, furan resin and the like.

According to the multiple sand control method for the directional well, preferably, the sand control curing agent comprises a water-soluble curing agent and an oil-soluble curing agent, and the proportion of the water-soluble curing agent to the oil-soluble curing agent is 7: 3; the water-soluble curing agent can be glycerol, phenol, acetone and the like; the oil-soluble curing agent can be selected from low molecular weight polyamides.

Due to the adoption of the technical scheme, the invention has the following advantages:

1. in the process of putting the heavy oil loose sandstone oil reservoir into production, the sand production oil layer is divided into different areas according to different sand production degrees at the later stage of oil layer production, after the different areas are sealed by using packers, sand prevention materials with different levels are additionally arranged in the annular area between the oil pipe and the casing pipe, so that the triple sand prevention purpose is achieved together with the sieve pipe and the artificial well wall, the sand prevention effect is improved to the maximum extent, and the oil layer is not greatly influenced and polluted.

2. The sand control material can keep a flowable state before being put into the directional well, the sand control curing agent is cured at the oil layer temperature after being put into the designated area of the well, the filled quartz sand, the high-temperature sand control material and the like are solidified in the designated area, and a certain liquid flow circulation capacity can be still kept after the sand control material is solidified, so that the oil well can play an effective sand control capacity and simultaneously ensure the liquid-phase oil flow to pass through after the scheme is implemented.

Drawings

FIG. 1 is a schematic diagram of a multiple sand control principle for a directional well according to an embodiment of the present invention;

the respective symbols in the figure are as follows:

1-a borehole; 2-a sleeve; 3-oil pipe; 4-ring cavity; 5-a packer; 601-first section sand control material, 602-second section sand control material, 603-third section sand control material, 604-fourth section sand control material.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention are described clearly and completely below, and it is obvious that the described embodiments are some, not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. As used herein, the terms "first," "second," "third," "fourth," and the like do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

As shown in fig. 1, the present invention provides a multiple sand control method for directional well using annular structure, comprising:

analyzing the sand grain size, the sand yield and the sand yield area of the oil well rock sample, predicting the sand content after the oil flow flows out at the later stage of the oil well, predicting the area with changed sand grain size of the horizontal oil layer of the oil well after the sand content, the sand grain diameter and the sand yield area of the directional well are found to be changed, and checking the comprehensive sand yield and the grain size distribution of the oil well;

after obtaining the detailed data of the comprehensive sand production amount and the particle size distribution of the oil well, dividing the sand production well section into well sections in different areas according to the sand production amount and the sand production particle size, such as: a fine grain size high sand production area, a fine grain size low sand production area, a coarse grain size high sand production area and the like;

selecting the diameter of quartz sand grains in the sand control material in advance, and blending and injecting the quartz sand grains into the sand control material; so that the optimal sand prevention effect is achieved;

injecting the prepared sand control material into the sand production front end region of the oil well through a high-pressure pipeline by using a high-pressure cement pump truck group, and filling and compacting after sufficient first-section sand control material is injected;

setting an annular packer 5 (a packer commonly used in the field) above the first section of sand control material 601 through a well rod to a preset position for fixing and packing, so as to ensure that the first section of sand control material 601 does not flee into or overflow from other subsequent well sections and play a role in supporting a casing and an oil pipe;

a well depth detector is put into the well to check whether the sand control material and the packer 5 reach the expected position, length and effect;

then replacing the sand control material, continuously injecting a second section of sand control material 602 through a high-pressure pump, compacting and setting a second section of packer for fixing and packing after ensuring that the complete area is filled, then continuously replacing the sand control material, injecting a third section of sand control material 603, and setting a third section of packer to a set position for fixing and packing an annular area; continuing to inject the fourth section of sand control material 604, then performing packing … … and so on, and filling the nth section of sand control material; and finally, the annular area of the sand production well section of the horizontal oil layer of the oil well achieves the multi-section sand prevention effect.

In the present invention, a complete section of the sand control design includes at least one packer 5 and a sand control material. The four-section sand control material filling is taken as an example for explanation. Positioning, fixing and packing different sand control materials by using an annular packer 5 between a plurality of sections of well sections; wherein the fourth section of sand control material 604 is located between the artificial bottom hole and the first section of packer; between the first section of packer and the second section of packer is a third section of sand control material 603; the second section of sand control material 602 is located between the second section of packer and the third section of packer; the first section of sand control material 601 is placed between the third section of packer and the fourth section of packer; before the packer 5 is put in, the sand-proof material is filled and compacted; and annular cement is used for sealing between the fourth section of annular packer and the wellhead. The annular packers 5 of the present invention are all identical packers and are designated as first, second, third and fourth … … nth packers for purposes of distinction.

In the invention, the sand control material consists of quartz sand, ceramsite, coating sand, a chemical sand control agent and a sand control curing agent.

In a preferred embodiment of the invention, the mass ratio of the quartz sand (or ceramsite), the coating sand, the chemical sand control agent and the sand control curing agent is 90: 10: 20: 25.

in a preferred embodiment of the present invention, the first sand control material 601, the second sand control material 602, the third sand control material 603, and the fourth sand control material 604 … … have different particle sizes of the quartz sand in the nth sand control material. Specifically, the particle size of the quartz sand in the first section of sand control material 601 is 2000 um-1500 um; the particle size of the quartz sand in the second section of sand control material 602 is 1500 um-1000 um; the particle size of the quartz sand in the third section of sand control material 603 is 1000 um-700 um; the particle size of the quartz sand in the fourth section of sand control material 604 is 700 um-500 um. The sand control particle size in each section of the sand control material is mainly smaller than the median of the main sand production particle size in each section.

In a preferred embodiment of the present invention, the chemical sand control agent comprises modified epoxy resin glue, unsaturated resin, furan resin, etc.

In a preferred embodiment of the invention, the sand control curing agent comprises a water-soluble curing agent and an oil-soluble curing agent, wherein the proportion of the water-soluble curing agent to the oil-soluble curing agent is 7: 3; the water-soluble curing agent can be selected from glycerol, phenol, acetone and the like; the oil-soluble curing agent can be selected from low molecular weight polyamides.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.