CN113153235B - A natural gas hydrate downhole hydraulic crushing recovery and separation device - Google Patents

Abstract

The invention discloses a natural gas hydrate underground hydraulic breaking, recovering and separating device, which relates to the field of petroleum and natural gas hydrate development and comprises the following components: a hydraulic spiral separation part, an internal and external fluid conversion device and a tubular cyclone separation device. The upper end and the lower end of the invention are connected with a drill rod, the upper end of a spiral separation part is connected with an inner fluid conversion device and an outer fluid conversion device, and the upper end of the inner fluid conversion device and the upper end of the outer fluid conversion device are connected with a pipe type spiral separation device. The invention utilizes the spiral and cyclone separation coupling principle to realize the secondary crushing and the gel breaking of solid-phase particles of the hydrate, and also can realize the underground in-situ real-time multiple separation and backfill of the high-sand content mixed fluid in the conventional petroleum or hydrate recovery, thereby better solving the problem that the high-sand content hydrate causes serious erosion and blockage to equipment and the like in the underground mixed fluid recovery.

Description

A natural gas hydrate downhole hydraulic crushing recovery and separation device

technical field

The invention relates to the field of petroleum and natural gas hydrate development, in particular to an underground hydraulic crushing, recovery and separation device for natural gas hydrate.

Background technique

Natural gas hydrate (hereinafter referred to as hydrate) is a new type of "clean energy" that occurs at a specific temperature and pressure and has the characteristics of high density, wide distribution, shallow burial, and large scale. Under the theoretical standard state, ^1m3 of natural gas hydrate can release ^164m3 of methane gas, which has attracted much attention because of its huge energy, but these characteristics also bring potential dangers and new technical requirements to the hydrate development process. At present, most gas hydrates are characterized by shallow burial depth, weak cementation, instability, no tight caprock, and high sand content (mainly micron-scale ultra-fine-fine-grained silt and medium-coarse-grained silt) with a particle size spanning However, in the existing natural gas hydrate development methods, including the depressurization method, heat injection method and solid-state fluidized production method, etc., the large amount of sand produced leads to low pipeline transportation efficiency and poor sustainable production capacity. Problems such as production economic efficiency, engineering geological risks, and equipment failure, such as reservoir collapse in goaf areas, equipment blockage and wear, have seriously hindered the development of related technologies and equipment for offshore natural gas hydrate exploitation, and have even become a must for commercial hydrate exploitation. Fortress, the current problems faced by hydrate mining are:

(1) There may be large lumps of mud-sand mixed solids in the process of hydrate mining, and the existing separation device does not consider the secondary crushing of hydrate;

(2) The existing seabed hydrate desanding device has a complex structure, and the fault tolerance rate is low and the reliability is not good during the deep sea hydrate separation operation;

(3) In the actual mining process, after the drill bit or jet breaks the hydrate layer, there are often large lumps of hydrate-sediment mixture, which is prone to block the flow channel;

To sum up, in order to solve the serious problem of sand production in the current natural gas hydrate production, there is an urgent need for a downhole mud-sand separator that can break the cementation of hydrate, so as to realize the downhole raw material of mixed fluid with high sand content in the process of conventional hydrate recovery. Bits are stripped and backfilled in real time.

Contents of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. For this reason, the present invention, by inventing a natural gas hydrate downhole hydraulic crushing and separation device, can realize real-time separation and backfilling of natural gas hydrate downhole, can reduce the pumping power required to lift the return material, save energy consumption, and increase production , can realize the breaking of cementation of hydrate, and can avoid the erosive wear and clogging of the transportation pipeline by the mud and sand, and the separated mud and sand can be directly backfilled to the goaf underground.

The present invention is realized through the following technical solutions:

A natural gas hydrate downhole hydraulic crushing and separation device, including three parts: a spiral separation part, an internal and external fluid conversion device, and a tubular cyclone separation device; Knife, spiral crushing shell; the internal and external fluid conversion device is installed on the upper end of the spiral separation part; the tubular cyclone separation device is composed of a cyclone separation shell, a centering ring, a cyclone separation inner tube, a cyclone separator, a bearing Group II, hydraulic helical blades, shaft end fixed joints.

The spiral crushing reamer has a drilling fluid channel in the center and a helical blade on the outer layer. The spiral crushing reamer is processed with a spiral groove inside for the assembly of the hydraulic spiral blade, and the middle part is the power fluid channel I.

The spiral crushing shell has a hydrate intake port I on the surface of the shell.

The internal and external fluid conversion device has a conversion channel I and a conversion channel II inside, and the internal and external fluid conversion device has a taper thread pin I, a taper thread box, and a flat thread.

The upper part of the shaft end fixed joint is provided with a taper thread male buckle II, and the middle part is a power fluid channel II.

In summary, the downhole hydraulic crushing, recovery and separation device for natural gas hydrate in the embodiment of the present invention has at least the following beneficial effects:

In terms of gas hydrate exploitation:

(1) The present invention is provided with a spiral crushing reamer, which can realize the secondary crushing of bulk mud-sand mixed solids;

(2) The invention is suitable for solid-state fluidized mining technology, without complex mechanical structure, realizes the integration of hydraulic drive and crushing reamer, is suitable for the harsh environment of deep sea, and the separation method is simple and reliable.

(3) Using the principle of helical-swirl flow coupling to break the "weak cementation bond" between hydrate solid particles and mud-sand particles, so as to realize the breakage of hydrate cement, and realize the cross-scale micron-sized particles of natural gas hydrate mixed slurry Separation to improve the cleanliness of the returned hydrate slurry and achieve the effect of increasing production capacity;

The invention utilizes the secondary crushing of the reamer to discharge the mud and sand in situ after sand removal, which reduces the transportation volume of the standpipe, reduces the erosion, wear and blockage of the mud and sand on the shaft and equipment, and timely backfills the mud and sand separated in situ It can prevent breaking the dynamic balance of hydrate reservoirs and prevent collapse accidents during oil production.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment, wherein:

Fig. 1 is the overall structural representation of the present invention;

Fig. 2 is a schematic diagram of a spiral crushing reamer of the present invention;

Fig. 3 is a schematic diagram of the internal and external fluid conversion device of the present invention;

Fig. 4 is a three-dimensional view of the hydraulic spiral blade of the present invention;

Fig. 5 is a schematic diagram of the shaft end fixed joint of the present invention.

1-Sealing plug at the lower part of the inner tube, 2-Bearing group Ⅰ, 3-Spiral crushing reamer, 4-Spiral crushing shell, 5-Internal and external fluid conversion device, 6-Swirl separation shell, 7-Centering ring, 8-Swirl Separation inner pipe, 9-cyclone separator, 10-bearing group II, 11-hydraulic spiral blade, 12-fixed joint at shaft end, 301-drilling fluid channel, 302-helical blade, 303-spiral groove, 304- Power fluid channel Ⅰ, 4-screw broken shell, 401-hydrate suction port Ⅰ, 501-transition channel Ⅰ, 502-transition channel, 503-Ⅱ cone thread male buckle Ⅰ, 504-taper thread female buckle, 505-flat buckle Thread, 1201-taper thread pin II, 1202-power fluid channel II.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc. indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only In order to facilitate the description of the present invention and simplify the description, it does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the description of the present invention, several means more than one, and multiple means more than two. Greater than, less than, exceeding, etc. are understood as not including the original number, and above, below, within, etc. are understood as including the original number. If the description of the first and second is only for the purpose of distinguishing the technical features, it cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features relation.

In the description of the present invention, unless otherwise clearly defined, words such as setting, installation, and connection should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

In the description of the present invention, reference to the terms "one embodiment," "some embodiments," "exemplary embodiments," "examples," "specific examples," or "some examples" is intended to mean that the embodiments are A specific feature, structure, material, or characteristic described by or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

As shown in Figures 1 to 5, a natural gas hydrate downhole hydraulic crushing and separation device includes three parts: a spiral separation part, an internal and external fluid conversion device, and a tubular cyclone separation device; the spiral separation part is sealed by the lower part of the inner pipe Plug 1, bearing group I2, spiral crushing reamer 3, and spiral crushing shell 4; the internal and external fluid conversion device 5 is installed on the upper end of the spiral separation part; the tubular cyclone separation device consists of a cyclone separation shell 6, Central ring 7, cyclone separation inner pipe 8, cyclone separator 9, bearing group II 10, hydraulic spiral blade 11, shaft end fixed joint 12. The spiral crushing reamer 3 has a drilling fluid channel 301 in its central channel and a helical blade 302 in the outer layer. The spiral crushing reamer 3 is internally processed with a spiral groove 303 for the assembly of the hydraulic spiral blade 11. The middle part is Power fluid passage I304. The spiral crushing shell 4 has a hydrate suction inlet I401 on the surface of the shell. The internal and external fluid conversion device 5 has a conversion channel I 501 and a conversion channel II 502 inside, and the internal and external fluid conversion device 5 has a tapered thread male thread I 503 , a tapered thread box thread 504 , and a flat thread 505 . The shaft end fixed joint 12 is provided with a tapered thread pin II 1201 on the upper part, and a power fluid channel II 1202 on the middle part.

Working process of the present invention is as follows:

The power fluid drives the spiral crushing reamer process:

The power fluid is injected from the upper cyclone separation shell 6 and the cyclone separation inner pipe 8 annulus, passes through the internal and external fluid conversion device 5, enters the conversion channel II 502, enters the inside of the screw crushing reamer 3, drives the hydraulic screw blade 11, and further drives the screw The crushing reamer 3 rotates to crush blocky mud sand or hydrate. The power fluid finally flows through the inside of the shaft end fixed joint 12 and continues to flow downward.

Separation process of natural gas hydrate:

The natural gas hydrate mud-sand mixed liquid (hereinafter referred to as the production liquid) enters from the suction port and enters the spiral crushing shell 4 . The production fluid is crushed by the spiral crushing reamer 3, and the large block of mud and sand is broken into fine particles, and due to the centrifugal force, the spiral crushing reamer 3 also plays a role in breaking the cement of the natural gas hydrate. The production fluid enters the cyclone separation inner pipe 8 through the conversion channel I501, and after the separation of the cyclone separator 9, the mud and sand are directly discharged into the sea, and the production fluid after separation continues to flow upward.

The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, and within the scope of knowledge of those of ordinary skill in the art, various modifications can be made without departing from the spirit of the present invention. Variety. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other if there is no conflict.

Claims (3)

1. The utility model provides a natural gas hydrate is broken to retrieve separator in pit which characterized in that includes: a spiral separation part, an internal and external fluid conversion device (5) and a tubular cyclone separation device; the spiral separation part consists of an inner pipe lower part sealing plug (1), a bearing group I (2), a spiral crushing reamer (3) and a spiral crushing shell (4); the inner and outer fluid conversion devices (5) are arranged at the upper end of the spiral separation part; the tubular cyclone separation device comprises a cyclone separation shell (6), a centering ring (7), a cyclone separation inner tube (8), a cyclone separator (9), a bearing group II (10), a hydraulic spiral blade (11) and a shaft end fixing joint (12), wherein the outer layer of the spiral crushing reamer (3) is a spiral blade (302), a spiral groove (303) is machined in the spiral crushing reamer (3), the spiral groove (303) is used for assembling the hydraulic spiral blade (11), the middle part of the spiral crushing reamer (3) is a power liquid channel I (304), the upper part of the shaft end fixing joint (12) is provided with a conical thread male buckle II (1201), and the middle part of the shaft end fixing joint (12) is a power liquid channel II (1202); wherein a conversion channel I (501) and a conversion channel II (502) are arranged in the internal and external fluid conversion devices (5); produced liquid enters the interior of the cyclone separation inner pipe (8) through the conversion channel I (501), silt is directly discharged to the sea through the separation effect of the cyclone separator (9), and the separated produced liquid continues to flow upwards.

2. A natural gas hydrate downhole hydraulic fracturing, recovery and separation device as claimed in claim 1, wherein the shell surface of the spiral fracturing shell (4) has a hydrate suction inlet i (401).

3. A natural gas hydrate downhole hydraulic fracturing, recovery and separation device according to claim 1, wherein the inner and outer fluid conversion devices (5) are provided with a taper thread male thread I (503), a taper thread female thread (504) and a flat thread (505).

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