KR20170035377A

KR20170035377A - Offshore plant

Info

Publication number: KR20170035377A
Application number: KR1020150133619A
Authority: KR
Inventors: 김영훈; 남기일; 박상민
Original assignee: 현대중공업 주식회사
Priority date: 2015-09-22
Filing date: 2015-09-22
Publication date: 2017-03-31

Abstract

An offshore plant is disclosed in which the generation of hydrate in the pipeline is prevented.
The disclosed offshore plant is an offshore plant comprising a pipeline that is disposed on the seabed and constitutes a path for transporting the oil well fluid produced in the well to the offshore platform, wherein the pipeline is connected to the oil well and the oil well is transported A production line constituting the euro; And a gas injection tube constituted by the production pipe arranged in the inner flow path or disposed in the inner flow path of the production pipe and constituting a flow path in which the boiling gas generated in the sea platform flows in the direction of the oil well, Lt; / RTI >
According to such an offshore plant, the productivity of the oil well fluid can be improved.

Description

Offshore Plant {OFFSHORE PLANT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offshore plant, and more particularly, to an offshore plant in which the generation of hydrate is prevented in a pipeline to which a fluid is fed.

In general, an offshore plant is a facility for drilling crude oil or natural gas from oil wells and then pipelining it to an offshore platform.

These offshore plants require boosting equipment to increase and maintain the productivity of the oil wells by increasing the pressure of the pipeline or wells in the event that the pressure of the wells decreases and productivity drops.

Generally, the boosting facility is composed of a facility for generating a boiling gas and a facility for supplying the generated boiling gas to a well or drilling pipe (facility for collecting the oil well fluid and flowing it through the pipeline).

The offshore plant according to the prior art is installed and operated as a separate pipeline in which the pipeline through which the oil well flows and the gas injection pipeline into which the boiling gas is injected are separated from each other.

On the other hand, crude oil or natural gas transported through pipelines contains water molecules and a variety of materials such as methane, ethane, propane, butane, etc., and gas hydrates may be generated when these materials are in a specific condition .

Gas hydrate is a complex formed by water molecules and gases such as methane, ethane, propane, butane, etc. under a specific temperature and pressure condition and formed into an ice-like solid-state lattice structure.

Such gas hydrates tend to be produced at lower temperatures and higher pressures.

However, the offshore plant is prone to hydrate in the pipeline because pipelines located in the deep ocean are in a low temperature and high pressure environment.

The hydrate generated in the pipeline has a problem of causing a plugging phenomenon by blocking the flow path of the pipeline, causing a pipe explosion or damaging the facility.

It is an object of the present invention to provide an offshore plant capable of preventing hydrate generation in a pipeline as one aspect of the present invention.

As an aspect to attain at least part of the above-mentioned object, the present invention is an offshore plant comprising a pipeline that is arranged in the sea bed and constitutes a path for conveying the oil well fluid produced in a well to a sea platform, A production pipe connected to the oil well and constituting a flow path for the oil flow to the marine platform; And a gas injection tube constituted by the production pipe arranged in the inner flow path or disposed in the inner flow path of the production pipe and constituting a flow path in which the boiling gas generated in the sea platform flows in the direction of the oil well, And to provide an offshore plant that has been constructed.

In one embodiment, the gas injection tube is configured such that the production tube is disposed in an internal flow passage, and the boiling gas can flow at a distance between the gas injection tube and the production tube.

Also, in one embodiment, the pipeline may include a gas injection valve that injects boiling gas flowing into the gas injection tube into an internal flow path of the production tube.

Further, in one embodiment, a plurality of the gas injection valves may be provided at intervals along the longitudinal direction of the pipeline.

In one embodiment, the riser is connected to the pipeline and the marine platform to float in the sea, and the riser is connected to the production line and is connected to the production riser ; And a production riser is disposed in an internal flow path or disposed in an internal flow path of the production riser, and the boiling gas generated in the sea platform is connected to the gas injection pipe, And a gas injector for injecting gas.

According to the embodiment of the present invention having such a configuration, the productivity of the oil well fluid can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a configuration of an offshore plant according to a first embodiment of the present invention; FIG.
Figure 2 is a cross-sectional view of a pipeline included in the offshore plant shown in Figure 1;
3 is a schematic view showing the structure of a drilling pipe included in the offshore plant shown in Fig.
4 is a schematic view showing a configuration of an offshore plant according to a second embodiment of the present invention;
5 is a schematic view showing a configuration of a marine plant according to a third embodiment of the present invention;
6 is a schematic view showing a configuration of a marine plant according to a fourth embodiment of the present invention;

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Furthermore, the singular forms "a", "an," and "the" include plural referents unless the context clearly dictates otherwise.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

First, a marine plant according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG.

1 to 3, a marine plant 100 according to a first embodiment of the present invention includes a marine platform 110, a manifold 120, a drilling pipe 130, a pipeline 140, And may include a riser 150.

The sea platform 110 is a structure floating on the sea and connected to a riser 150 to be described later to receive and process the oil wells produced in the oil well W. [

The marine platform 110 may include a separator 112 and a gas compressor 114.

Here, the separator 112 is connected to a riser 152 of a riser 150, which will be described later, to separate the supplied oil fluid into oil and gas.

The gas compressor 114 is connected to a gas injection riser 154 of a riser 150 to be described later to generate and inject a boiling gas into the riser 154 for gas injection.

The manifold 120 may be installed on the sea floor to collect the oil wells produced in the plurality of oil wells W.

The drilling pipe 130 may be connected to the well W to form a path through which the well fluid is collected.

3, the drilling pipe 130 includes an inner pipe 132 to which the oil fluid is to be transferred, and a pipe line 132 that is configured to surround the outer surface of the inner pipe 132 in the form of a double pipe, And an outer tube 134 connected to the gas injection tube 144 of the heat exchanger 140 and into which the boiling gas is injected.

The drilling pipe 130 is provided with a pressure correction valve 136 through which the boiling gas injected into the outer pipe 134 is injected into the inner pipe 132.

When the pressure of the well W is lowered, the pressure correction valve 136 is opened and the boosting gas is injected into the inner pipe 132, so that the pressure of the oil fluid conveyed through the inner pipe 132 can be raised have.

3, a flow control valve 138 for controlling the flow rate of the oil flow is provided in the channel where the inner pipe 132 is connected to the production pipe 142 of the pipeline 140 to be described later And a choke valve 139 for controlling the flow rate of the boosting gas may be provided in the channel through which the outer tube 134 is connected to the gas injection tube 144 of the pipeline 140 to be described later.

The pipeline 140 may be connected to the manifold 120 and disposed at the seabed so as to constitute a path through which the collected well fluid is transferred to the offshore platform 110.

Such a pipeline 140 may include a production tube 142 and a gas injection tube 144.

The production pipe 142 may be connected to the oil well W to constitute a channel through which the oil well fluid is transferred to the separator 112 of the marine platform 110.

In one embodiment, the production tube 142 may have an inlet connected to the manifold 120 and an outlet connected to a production riser 152, described below.

The gas injection pipe 144 may be configured such that the production pipe 142 is disposed in the inner flow path or in the inner flow path of the production pipe 142.

In one embodiment, the gas injection tube 144 may have an inlet connected to the gas compressor 114 and an outlet connected to the manifold 120.

The gas injection pipe 144 may constitute a flow path in which the boiling gas generated in the gas compressor 114 of the marine platform 110 flows in the direction of the oil well W. [

Meanwhile, the pipeline 140 may have a double pipe structure through the production pipe 142 and the gas injection pipe 144.

In one embodiment, the gas injection tube 144 is configured such that the production tube 142 is disposed in the inner flow path as shown in FIGS. 1 and 2, and the gas injection tube 144 is disposed between the gas injection tube 144 and the production tube 142 It is possible to flow the boiling gas at intervals. That is, in the dual pipe structure 140, the production pipe 142 constitutes the inner pipe, and the gas injection pipe 144 constitutes the outer pipe.

In such a configuration, the pipeline 140 can serve to insulate the boiling fluid that flows into the gas injection pipe 144 and the gas-injection pipe 144 itself from the oil flowing into the production pipe 142 with the seawater have.

Further, by adjusting the temperature of the boiling gas injected into the gas injection tube 144, the temperature of the production tube 142 may be adjusted.

If sufficient insulation is provided between the cold seawater and the production pipe 142, hydrate formation in the production pipe 142 is prevented.

On the other hand, in one embodiment, the pipeline 140 may further include a gas injection valve 146.

2, the gas injection valve 146 is provided between the production pipe 142 and the gas inlet, and injects the boiling gas, which flows into the gas injection pipe 144, into the inner channel of the production pipe 142 .

In one embodiment, a plurality of gas injection valves 146 may be provided spaced along the length of the pipeline 140.

In this configuration, by controlling the gas injection valve 146 at the position where the pressure correction is required, the boiling gas is injected into the production pipe 142, so that the pressure inside the production pipe 142 can be adjusted to a desired pressure.

The riser 150 is a kind of pipe connected between the pipeline 140 and the sea platform 110 to float in the sea.

In one embodiment, the riser 150 may be comprised of a riser 152 for production and a riser 154 for gas injection.

The production riser 152 may be connected to the production pipe 142 of the pipeline 140 and the separator 112 of the offshore platform 110 to constitute a flow path through which the oil well fluid is delivered to the separator 112 .

The gas injection riser 154 is connected to the gas injection pipe 144 of the pipeline 140 and the gas compressor 114 of the offshore platform 110 so that the boiling gas is supplied to the gas injection pipe 144 The flow can be configured.

In one embodiment, the production riser 152 and the gas injection riser 154 may be composed of two pipes separated from each other as shown in Fig.

At this time, the production riser 152 and the gas injection riser 154 may be separated from each other by branching the production pipe 142 and the gas injection pipe 144 from the end of the pipeline 140 have.

Next, a marine plant 100 according to a second embodiment of the present invention will be described with reference to FIG.

4, the offshore plant 100 according to the second embodiment of the present invention differs from the offshore plant 100 according to the first embodiment of the present invention shown in FIG. 1 in that a production riser 152 And the gas injection riser 154 are not separated from each other.

To this end, the gas injection riser 154 may be configured such that the production riser 152 is disposed in the inner flow path or disposed in the inner flow path of the production riser 152.

In one embodiment, the gas injection riser 154 may be configured in the form of an outer tube that surrounds the production riser 152, similar to the gas injection tube 144 of the pipeline 140.

Here, the production riser 152 may be insulated with seawater through the boiling gas flowing to the gas injection riser 154 and the riser 154 itself for gas injection.

Next, a marine plant 100 according to a third embodiment of the present invention will be described with reference to FIG.

5, an offshore plant 100 according to a third embodiment of the present invention is similar to the offshore plant 100 according to the first embodiment of the present invention shown in FIG. 1, The gas injection pipe 144 may be disposed in the inner flow path of the production pipe 142. That is, in the third embodiment of the present invention, the pipe line 140 of the double pipe structure can be formed by the production pipe 142 as the outer pipe and the gas injection pipe 144 as the inner pipe.

At this time, the gas injection pipe 144 may be connected to the gas compressor 114, and the production pipe 142 may be connected to the separator 112.

In this third embodiment of the present invention, the boosting gas flowing into the gas injection tube 144 can transfer heat to the oil fluid flowing through the production tube 142 inside the production tube 142.

In the offshore plant 100 according to the third embodiment of the present invention, since the cross-section of the flow channel of the production pipe 142 is formed in the shape of a ring, the oilfield fluid can be dispersed and flow relatively thinly, The heat of the boiling gas flowing into the pipe 142 can be evenly distributed throughout the oil fluid.

Finally, referring to FIG. 6, a marine plant 100 according to a fourth embodiment of the present invention will be described.

6, the offshore plant 100 according to the fourth embodiment of the present invention differs from the offshore plant 100 according to the third embodiment shown in FIG. 5 in that the production riser 152 and the gas injection The riser 154 may be configured as a double pipe structure instead of being separated from each other.

For this purpose, the production riser 152 may be configured in the form of an outer tube that surrounds the gas injection riser 154, as well as the gas injection tube 144 of the pipeline 140.

As described above, the offshore plant 100 according to the embodiments of the present invention can flow oiling fluid and boiling gas through one pipe facility having a double pipe structure, thereby simplifying the submarine facilities, reducing the installation cost, And the process is simplified.

In the offshore plant 100 according to the embodiments of the present invention, since the boiling gas and the gas injection pipe 144 are insulated from the production pipe 142, the heat insulation performance of the pipeline 140 is improved, Thereby improving the production efficiency of the oil and the gas.

In addition, the offshore plant 100 according to embodiments of the present invention can inject boiling gas into the pipeline 140, so that the temperature and pressure of the pipeline 140 can be controlled, And has an advantage that operation control is easy.

While the present invention has been particularly shown and described with reference to particular embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention as defined by the following claims I would like to make it clear.

100: offshore plant 110: offshore platform
112: separator 114: gas compressor
120: Manifold 130: Drilling pipe
132: inner tube 134: outer tube
136: Pressure compensating valve 138: Flow regulating valve
139: Choke valve 140: Pipeline
142: Production pipe 144: Gas injection pipe
146: gas injection valve 150: riser
152: production riser 154: gas injection riser
W: Well

Claims

1. An offshore plant comprising a pipeline that is disposed in the seabed and constitutes a path for transporting a well oil fluid produced in a well to a marine platform,
The pipeline includes:
A production pipe connected to the oil well and constituting a flow path for the oil flow to the marine platform; And
A gas injection pipe constituted such that the production pipe is disposed in an inner flow path or disposed in an inner flow path of the production pipe, and a boiling gas generated in the sea platform forms a flow path in a direction of the oil flow;
The marine plant consists of a double pipe structure.

The method according to claim 1,
Wherein the gas injection pipe is configured such that the production pipe is disposed in an internal flow path, and the boiling gas flows at a distance between the gas injection pipe and the production pipe.

3. The method of claim 2,
Wherein the pipeline includes a gas injection valve for injecting a boiling gas flowing into the gas injection tube into an internal flow path of the production tube.

The method of claim 3,
Wherein the plurality of gas injection valves are provided at intervals along the longitudinal direction of the pipeline.

The method according to claim 1,
And a riser connected between the pipeline and the sea platform to float in the sea,
The riser
A production riser connected to the production pipe and constituting a flow path for the oil flow to the marine platform; And
Wherein the production riser is disposed in an inner flow path or is disposed in an inner flow path of the production riser and connected to the gas injection pipe to constitute a flow path for the boiling gas generated in the sea platform to flow into the gas injection pipe And a gas injection riser.