JP6499500B2 - Downhole compressor - Google Patents

Description

  The present invention relates to a downhole compression apparatus used in a gas well or the like.

  In a downhole compression apparatus in a casing such as a gas well, a fluid in which a gas and a liquid are mixed flows in a flow path on the upstream side (bottom side) thereof. In the case of a gas well, a liquid composed of water or oil contained in the gas is an unnecessary substance and is often called slag. Therefore, in the downhole compression apparatus, a separator that separates the liquid (slag) from the fluid in which the liquid (slag) is mixed with the gas is provided. That is, unnecessary liquid (slag) is separated and removed by the separator provided on the upstream side of the compressor that compresses the gas (collected gas).

  The separator has a range of droplet diameters that can efficiently separate the liquid (slag). When the droplet diameter is out of the range, the droplet passes through the separator. That is, droplets smaller than or larger than a predetermined droplet diameter (slag) pass through the separator. In particular, when a gas mixed with a large amount of liquid flows into the separator, the droplet diameter naturally becomes excessively large. Therefore, the separator cannot separate the droplets, and the droplets that have not been separated flow into a compressor provided downstream of the separator. As a result, the compressor receives an inflow of a large amount of liquid (slag) and breaks due to overload.

  In order to solve the technical problem in such a downhole compression apparatus, for example, in Patent Document 1, a part of the gas compressed by the compressor is caused to flow backward to the upstream side of the separator through the recycle channel and ejected from the nozzle. By doing so, a technology for crushing large diameter droplets (slag) is disclosed.

International Publication No. 2013/40184

  According to the technique for crushing droplets (slag) described in Patent Document 1, it is possible to crush slag having a large diameter. However, when the separator receives a large amount of slag, it is difficult to crush all of the large amount of slag to an appropriate size that can be separated by the separator by the technique described in Patent Document 1. Therefore, when the slag is not sufficiently crushed, the slag passes through the separator and flows into the compressor, which may cause the compressor to break.

  Therefore, an object of the present invention is to provide a downhole compression apparatus that can prevent a large slag compressor from flowing into the compressor and prevent the compressor from being damaged.

  In order to achieve the above object, a downhole compressor according to the present invention is provided in a cylindrical casing, compresses a fluid taken in from one end of the casing in the casing, A separator disposed in the casing on the upstream side of the compressor along the flow direction, for separating and removing slag contained in the fluid, and along the flow direction of the fluid, A slag crushing grid disposed in the casing on the upstream side and crushing slag larger than its own lattice among slag contained in the fluid and allowing the fluid containing slag smaller than the lattice to pass through. It is characterized by comprising.

  ADVANTAGE OF THE INVENTION According to this invention, the downhaul compression apparatus which can prevent inflow to the compressor of a big slag and can prevent the failure | damage of a compressor is provided.

The figure which showed typically the example of the longitudinal cross-section of the downhole compression apparatus which concerns on the 1st Embodiment of this invention. The figure which showed the example of the (a) top view and (b) perspective view of the slag crushing lattice which concern on the 1st Embodiment of this invention. The figure which showed the 1st modification of the slag crushing lattice used with the downhole compression apparatus which concerns on the 1st Embodiment of this invention. The figure which showed the 2nd modification of the slag crushing lattice used with the downhole compression apparatus which concerns on the 1st Embodiment of this invention. The figure which showed typically the example of the longitudinal cross-section of the downhole compression apparatus which concerns on the 2nd Embodiment of this invention. The figure which showed the example of the perspective view of the slag crushing lattice which concerns on the 2nd Embodiment of this invention. The figure which showed typically the example of the longitudinal cross-section of the downhole compression apparatus which concerns on the modification of the 2nd Embodiment of this invention. The figure which showed typically the example of the longitudinal cross-section of the downhole compression apparatus which concerns on the 3rd Embodiment of this invention. The figure which showed the example of the perspective view of the screw wing | blade provided in the downhole compression apparatus which concerns on the 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to a common component and the overlapping description is abbreviate | omitted.

<First Embodiment>
FIG. 1 is a diagram schematically showing an example of a longitudinal sectional structure of a downhole compression apparatus 10 according to the first embodiment of the present invention. As shown in FIG. 1, the downhole compression apparatus 10 is an apparatus that takes in a fluid 60 that flows in from the bottom of a cylindrical casing 20 such as a gas well, compresses the fluid 60 in the casing 20, and supplies the fluid 60 to the top of the casing 20. . The downhole compression apparatus 10 according to the present embodiment includes a compressor 30, a separator 40, and a slag crushing grid 50. Here, as the compressor 30 and the separator 40, both known general compressors and separators are used.

  In general, the fluid 60 flowing from the bottom of the casing 20 is a mixture of a gas 70 and a slag 80 made of water drops, oil drops, or the like. As described above, the slag 80 may damage the compressor 30. Therefore, a separator 40 that separates and removes the slag 80 is disposed on the upstream side (bottom side) of the compressor 30 in the casing 20, and the slag 80 is removed from the fluid 60 by the separator 40. In FIG. 1, the block arrows indicate the flow direction of the fluid 60 composed of the gas 70 and the slag 80.

  In the known general separator 40, for example, a rotational force is applied to the fluid 60 passing through the separator 40, and the gas 70 and the slag 80 are separated from each other by the principle of centrifugal separation. However, in such a separator 40, the light and small slag 80 is not sufficiently separated from the gas 70, and the heavy large slag 80 that is not rotated by the applied rotational force is also sufficiently separated. Absent. Therefore, the light minute slag 80 and the heavy large slag 80 are not removed by the separator 40 and flow into the compressor 30.

  In this case, the light minute slag 80 does not become a heavy load on the compressor 30, but the heavy large slag 80 becomes a large load on the compressor 30, and when the overload is caused, the compressor 30 is damaged. There is a fear. Therefore, in this embodiment, the slag crushing grid 50 for crushing the large slag 80 into the small slag 80 is provided on the further upstream side (bottom side) of the separator 40.

  Drawing 2 is a figure showing the example of (a) top view and (b) perspective view of slag crushing lattice 50 concerning a 1st embodiment. As shown in FIGS. 2 (a) and 2 (b), the slag crushing grid 50 is arranged such that a plurality of horizontal transverse bars 51 and vertical longitudinal bars 52 that are arranged in parallel with each other intersect each other. Configured. Then, both end portions of the horizontal beam 51 and the vertical beam 52 are fixed to the inner wall of the casing 20. That is, the slag crushing grid 50 is fixed to the inner wall of the casing 20 so that the grid surface is substantially orthogonal to the length direction of the casing 20. At this time, it is assumed that the size (cross-sectional area) of each lattice 53 surrounded by the horizontal beam 51 and the vertical beam 52 in the slag crushing lattice 50 is substantially uniform. Moreover, although the lattice plane of the slag crushing lattice 50 is assumed to be substantially perpendicular to the central axis of the casing 20, there may be some inclination.

  Therefore, in this embodiment, when the fluid 60 flowing in from the bottom of the casing 20 reaches the position where the slag crushing lattice 50 is disposed, the slag 80 smaller than the gas 70 and the lattice 53 in the fluid 60 is Pass through the slag crushing grid 50. On the other hand, the slag 80 larger than the lattice 53 collides with the slag crushing grid 50 and is crushed and becomes smaller. The slag 80 that has become smaller than the lattice 53 passes through the slag crushing lattice 50.

  That is, even if a large slag 80 is included in the fluid 60 flowing from the bottom of the casing 20, the large slag 80 is crushed by the slag crushing lattice 50 when passing through the slag crushing lattice 50, and from the lattice 53 Becomes a small slag 80. Therefore, by appropriately determining the size of the lattice 53, the size of the slag 80 passing through the slag crushing lattice 50 can be made a size that can be efficiently separated by the separator 40.

  In that case, most of the slag 80 except for the minute slag 80 is removed by the separator 40, so that at least the large slag 80 does not flow into the compressor 30. As a result, the compressor 30 is not overloaded, and the compressor 30 is prevented from being damaged. Therefore, in this embodiment, the problem of the prior art that the big slag 80 passes the separator 40, flows into the compressor 30, and causes the compressor 30 to be broken is solved.

  In the slag crushing lattice 50 shown in FIG. 2, the horizontal beam 51 and the vertical beam 52 are made of a plate material made of, for example, stainless steel, but are made of a rod material or wire made of stainless steel or the like. It may be.

(First modification of the first embodiment)
FIG. 3 is a view showing a first modification of the slag crushing lattice 50 used in the downhole compression apparatus 10 according to the first embodiment of the present invention. The horizontal beam 51 and the vertical beam 52 of the slag crushing grid 50 shown in FIG. 2 are composed of straight plate material, bar material, wire material, etc. In the first modification shown in FIG. The horizontal beam 51a and the vertical beam 52a of the lattice 50a are configured by wavy plate material, bar material, wire material, or the like. Here, it is assumed that the size (cross-sectional area) of each lattice 53a surrounded by the horizontal beam 51a and the vertical beam 52a is substantially uniform.

  Also in this modification, the slag crushing lattice 50a can crush the large slag 80 to obtain a slag 80 having a size corresponding to the size of the lattice 53a. Therefore, the size of the slag 80 flowing into the separator 40 can be made a size that can be efficiently separated by the separator 40. Therefore, also in this modified example, it is possible to prevent the large slag 80 from flowing into the compressor 30 and to obtain the same effect as in the first embodiment that can prevent the compressor 30 from being damaged.

(Second modification of the first embodiment)
FIG. 4 is a view showing a second modification of the slag crushing lattice used in the downhole compression apparatus 10 according to the first embodiment of the present invention. As shown in FIG. 4, in the slag crushing grid 50b according to the second modified example, a plurality of circular (arc-shaped) horizontal bars 51b having different diameters are arranged concentrically around the central axis of the casing 20, A plurality of straight vertical bars 52 b are arranged radially so as to pass through the central axis of the casing 20. In this case, the size (cross-sectional area) of the lattice 53b surrounded by the horizontal beam 51b and the vertical beam 52b is small in the central portion in the casing 20 and large in the peripheral portion.

  Therefore, when the fluid 60 composed of the gas 70 and the slag 80 passes through the slag crushing lattice 50a, the average size of the slag 80 after passing is small at the central portion in the casing 20 and large at the peripheral portion. Therefore, the fluid 60 containing the slag 80 that is small at the center in the casing 20 and that is large at the peripheral edge flows into the separator 40. In other words, it can be considered that the fluid 60 with some separation of the slag 80 flows into the separator 40. Therefore, in this modification, the separator 40 can separate the slag 80 more efficiently.

  Therefore, also in this modified example, the separator 40 efficiently determines the size of the slag 80 after passing through the separator 40 by appropriately determining the number and interval of the plurality of circular horizontal bars 51b and the radial vertical bars 52b. The size can be well separated. Therefore, in this modification, it can prevent more effectively that the big slag 80 flows in into the compressor 30, and can prevent the damage of the compressor 30 more effectively.

<Second Embodiment>
FIG. 5 is a diagram schematically showing an example of a longitudinal sectional structure of a downhole compression apparatus 10c according to the second embodiment of the present invention. FIG. 6 is a view showing an example of a perspective view of the slag crushing lattice 50c according to the second embodiment.

  As shown in FIG. 5, the downhole compression device 10 c according to the second embodiment is a device that compresses the fluid 60 flowing in from the bottom of the cylindrical casing 20 in the casing 20 and supplies the compressed fluid 60 to the top of the casing 20. Yes, and includes a compressor 30, a separator 40, and a slag crushing grid 50c. The downhole compression apparatus 10c according to the second embodiment is the downhole according to the first embodiment, except that the shape of the slag crushing grid 50c is different from the slag crushing grid 50 shown in FIGS. It is the same as the hall compression device 10.

  As shown in FIGS. 5 and 6, in the second embodiment, the slag crushing grid 50 c has a part or the whole of the grid surface protruding in a convex shape toward the upstream side of the flow of the fluid 60. ing. As shown in FIG. 6, the slag crushing grid 50c is constituted by, for example, linear or arc-shaped bars arranged on the bottom and side surfaces of an inverted half cone, and the shape of the grid surface is an inverted half cone cage. It has a shape.

  Incidentally, in the slag crushing lattice 50c illustrated in FIG. 6, the bottom surface portion of the inverted half cone is configured by a lattice composed of a horizontal beam and a vertical beam as shown in FIG. It is composed of a lattice composed of a circular beam centered on the cone axis and a linear beam along a straight line passing through the apex of the cone. In the case of the slag crushing lattice 50c having such a shape, the size of the lattice is substantially uniform at the center portion in the casing 20, that is, the bottom portion of the inverted half cone. On the other hand, in the peripheral part in the casing 20, that is, the side part of the inverted half cone, the size of the lattice becomes larger toward the peripheral part. And the size of the lattice can be made larger than the size of the lattice on the bottom surface.

  Therefore, when the slag crushing grid 50c having such a shape is disposed in the casing 20 on the upstream side of the separator 40, the large slag 80 contained in the fluid 60 flowing from the bottom of the casing 20 is crushed by the slag crushing grid 50c. The slug 80 is smaller than the lattice. Therefore, the size of the slag 80 crushed by the slag crushing grid 50c can be made a size that can be efficiently separated by the separator 40 by appropriately determining the size of the grid of the slag crushing grid 50c.

  In the case of this embodiment, as in the case of the example of FIG. 4, the average size of the slag 80 after passing through the slag crushing grid 50 c can be reduced at the center in the casing 20 and increased at the periphery. it can. Therefore, in this embodiment, the separator 40 can separate the slag 80 more efficiently. Therefore, in this embodiment, it can prevent more effectively that the big slag 80 flows in into the compressor 30, and can prevent the damage of the compressor 30 more effectively.

  In the example shown in FIG. 6, the shape of the lattice surface of the slag crushing lattice 50 c is an inverted half-cone cage shape, but may be, for example, a ball (container) shape formed of a part of a spherical surface. Good. As an example of the shape of the slag crushing grid 50c in this case, for example, the slag crushing grid 50b shown in FIG. 4 has a grid surface protruding in a convex spherical shape toward the upstream side of the flow of the fluid 60. Can do.

(Modification of the second embodiment)
FIG. 7 is a diagram schematically showing an example of a longitudinal sectional structure of a downhole compression apparatus 10d according to a modification of the second embodiment of the present invention. As shown in FIG. 7, in the downhole compression apparatus 10d according to this modification, a part or the whole of the lattice surface of the slag crushing lattice 50d protrudes in a convex shape on the downstream side (upper side) of the flow of the fluid 60. This is different from the downhole compression apparatus 10c according to the second embodiment shown in FIG. Therefore, as the slag crushing grid 50d, an inverted half-cone cage-like slag crushing grid 50c shown in FIG. 6 can be used as it is upside down.

  That is, this modification example is different from the second embodiment only in the protruding direction of the lattice surface of the slag crushing grating 50d, and thus this modification example also has the same function and effect as the second embodiment. Play. Therefore, also in this modification, it is possible to prevent the large slag 80 from flowing into the compressor 30 and prevent the compressor 30 from being damaged.

<Third Embodiment>
FIG. 8 is a diagram schematically showing an example of a longitudinal sectional structure of a downhole compression apparatus 10e according to the third embodiment of the present invention. FIG. 9 is a diagram showing an example of a perspective view of a screw blade 90 provided in the downhole compression apparatus 10e according to the third embodiment.

  As shown in FIG. 8, the downhole compression device 10 e according to the third embodiment is a device that compresses the fluid 60 flowing from the bottom of the cylindrical casing 20 in the casing 20 and supplies the compressed fluid 60 to the top of the casing 20. The compressor 30, the separator 40, the slag crushing grid 50, and the screw blades 90 are provided. The downhole compression apparatus 10e according to the third embodiment has a downhole according to the third embodiment shown in FIG. 1 in that a screw blade 90 is additionally provided on the upstream side of the separator 40. Different from the compression device 10.

  As shown in FIGS. 8 and 9, the screw blade 90 is disposed and fixed between the shaft member 91 and the inner wall of the casing 20. Here, it is assumed that four screw blades 90 are configured, and all of them are attached to the inner wall of the casing 20 and the outer wall of the shaft member 91 so as to be inclined with respect to the axial direction of the casing 20. Therefore, the fluid 60 rising from the bottom of the casing 20 flows obliquely upward along the screw blades 90 and the inner wall of the casing 20. As a result, as the fluid 60 passes through the screw blades 90, vortices are created therein. Here, the spiral block arrow shown in FIG. 8 represents the vortex generated in the fluid 60, and the thick line arrow shown in FIG. 9 represents the flow direction of the fluid 60 passing through the screw blade 90. Yes.

  As described above, when a vortex is generated in the fluid 60, the large (heavy) slag 80 is pushed toward the peripheral edge of the casing 20, and the small (light) slag 80 remains in the vicinity of the center of the casing 20. Therefore, when the fluid 60 passes through the slag crushing grid 50, particularly large slag 80 is crushed into small pieces by the slag crushing grid 50, but on the average, the large slag 80 flows into the peripheral portion of the separator 40, and the separator 40 On the average, small slag flows into the center.

  That is, since the slag 80 to be separated by the separator 40 flows into the separator 40 in a state where it is separated to some extent in advance, the separator 40 can separate the slag 80 more efficiently. Therefore, in the present embodiment, it is possible to more effectively prevent the large slag 80 from flowing into the compressor 30, and it is possible to more effectively prevent the compressor 30 from being damaged.

  8 and 9, the number of screw blades 90 is four, but the number is not limited to four and may be any number. Moreover, although the screw blade 90 is fixed between the inner wall of the casing 20 and the outer wall of the shaft member 91, the shaft member 91 may not be provided.

  In the downhole compression apparatus 10e according to the present embodiment, the slag crushing grid 50 shown in FIG. 2 is used. The slag crushing grid 50 is a slag crushing grid having the structure shown in FIGS. 50b-50d may be sufficient. Furthermore, when the slag crushing grid 50 as shown in FIG. 2 composed of the horizontal beam 51 and the vertical beam 52 is used, the size of the lattice 53 at the center is reduced and the size of the lattice 53 at the peripheral portion is reduced. You may enlarge it.

  The present invention is not limited to the embodiments and modifications described above, and includes various modifications. For example, the above-described embodiments and modifications have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. In addition, a part of the configuration of an embodiment or modification can be replaced with the configuration of another embodiment or modification, and the configuration of another embodiment or modification can be replaced with another embodiment or modification. It is also possible to add the following configuration. In addition, with respect to a part of the configuration of each embodiment or modification, the configuration included in another embodiment or modification may be added, deleted, or replaced.

10, 10c, 10d, 10e Downhole compressor 20 Casing 30 Compressor 40 Separator 50, 50a, 50b, 50c, 50d Slag crushing grid 51, 51a, 51b Horizontal beam 52, 52a, 52b Vertical beam 53, 53a, 53b Grid Eye 60 Fluid 70 Gas 80 Slag 90 Screw blade 91 Shaft

Claims (8)

A compressor that is disposed in a cylindrical casing and compresses the fluid taken in from one end of the casing in the casing;
A separator that is disposed in the casing on the upstream side of the compressor along the direction of flow of the fluid, and separates and removes slag contained in the fluid;
Along the flow direction of the fluid, disposed in the casing on the upstream side of the separator, and crushes slag larger than its own lattice among the slag contained in the fluid, and more than the lattice A slag crushing grid for passing the fluid containing small slag;
The downhole compression apparatus characterized by comprising. 2. The slag crushing grid is composed of a horizontal beam and a vertical beam that intersect each other, and at least one of the horizontal beam and the vertical beam is formed of a linear plate material, a bar material, or a wire material. The downhole compression apparatus as described in. The slag crushing lattice is composed of a cross beam and a vertical beam that intersect each other, and at least one of the horizontal beam and the vertical beam is configured by a wavy plate material, a bar material, or a wire material. The downhole compression apparatus as described in. The slag crushing grid consists rungs and vertical bar intersect each other, wherein the rungs are arcuate plate, downhole compression apparatus according to claim 1, characterized in that it is constituted by the bar or wire . The downhole compression apparatus according to claim 1, wherein the slag crushing grid has a grid surface protruding in a convex shape upstream of the fluid flow. The downhole compressor according to claim 1, wherein the slag crushing grid has a grid surface protruding in a convex shape downstream of the fluid flow. The size of the lattice of the slag crushing lattice is larger in the lattice located in the peripheral portion in the casing than the lattice located in the central portion in the casing. Downhole compressor. The screw blade is further provided in the casing on the upstream side of the slag crushing lattice along the direction of the fluid flow, and generates a vortex in the fluid that has passed therethrough. The downhole compression apparatus as described in.

Images