NZ588118A

NZ588118A - Separator for receiving a pressurized fluid containing at least one solid material and one liquid material

Info

Publication number: NZ588118A
Application number: NZ588118A
Authority: NZ
Inventors: Philippe Espinasse
Original assignee: Technip France
Priority date: 2008-03-21
Filing date: 2009-03-20
Publication date: 2012-03-30
Also published as: ES2597902T3; WO2009125106A3; EP2262577B1; MX2010010307A; EP2262577A2; JP5627567B2; BRPI0908601B1; FR2928960A1; BRPI0908601A2; FR2928960B1; MX345370B; PT2262577T; JP2011522977A; WO2009125106A2

Abstract

Disclosed is a separator comprising a pressurized vessel (62) and first and second tank (64A, 64B) for depressurizing a pressurized liquid flow rich in solid material produced in the vessel (92). It comprises a directional control valve (66) connecting the vessel and each depressurizing tank (64). The directional control valve is movable between a first configuration in which it directs the pressurized flow to the first tank and depressurizes the second tank, and a second configuration in which it directs the pressurized flow to the second tank and depressurizes the first tank.

Description

Received at IPONZ 30 November 2011 1 Separator for receiving a pressurized fluid containing at least one solid material and one liquid material.

The present invention concerns a separator for continuously receiving a pressurized fluid, the pressurized fluid containing at least one divided solid material and one liquid, the separator being of the type comprising: - a pressurized vessel for separating the pressurized fluid into a flow rich in solid material, and into at least one pressurized flow poor in solid material, the pressurized vessel comprising a pressurized fluid injection inlet, a lower discharge outlet for the pressurized flow rich in solid material, and at least one discharge outlet of the or each pressurized flow poor in solid material.

Such a separator is intended to be connected for instance to the outlet of a transport pipe for a pressurized fluid containing divided solid material taken from the bottom of an expanse of water, pressurized water, and pressurized gas.

The transport pipe is for example arranged in an extraction device intended for mining operations in sea beds, or earthworking of sea beds for the placement of hydrocarbon production equipment.

Known from US 4,232,903 is such an extraction device comprising surface equipment carried by a ship, a bottom assembly provided with an underwater vehicle for extracting solid material, and a pipe for transporting the solid material connecting the bottom assembly to the surface equipment.

To bring the material withdrawn from the bottom to the surface, pressurized gas is conveyed from the surface equipment to an intermediate point of the transport pipe to be injected into the pipe. The mixture of water and solid material present in the pipe is thus lightened above the gas injection point, which drives the pressurized fluid toward the surface equipment.

However, this conveyance requires that the gas be compressed at a high pressure to inject it into the riser. The ship must therefore carry a large compressor, which is not very economical or practical.

To ensure good productivity, it is also necessary to continuously process the pressurized fluid coming from the transport pipe to separate it into a flow rich in solid material, a liquid flow and a gaseous flow, and to depressurize the flow rich in solid material so it can be stored on the ship, without having to interrupt the circulation of fluid in the transport pipe.

Received at IPONZ 30 November 2011 2 One aim of at least preferred embodiments of the invention is to obtain a separator for an extraction device that makes it possible both to continuously separate a pressurized fluid to obtain a depressurized flow rich in solid material, and to recover a pressurized flow poor in solid material, so it can be recycled in the 5 device.

To that end, a first aspect of the invention concerns a separator for continuously receiving a pressurized fluid, the pressurized fluid containing at least one divided solid material and one liquid, the separator being of the type comprising: - a pressurized vessel for separating the pressurized fluid into a flow rich in 10 solid material, and into at least one pressurized flow poor in solid material, the pressurized vessel comprising a pressurized fluid injection inlet, a lower discharge outlet for the pressurized flow rich in solid material, and at least one discharge outlet of the or each pressurized flow poor in solid material, wherein the separator comprises: - at least one first and one second tank for depressurizing a pressurized flow rich in solid material, each tank defining a closed inner space emerging through an inlet for introducing the pressurized flow rich in solid material and through a depressurization outlet, provided with a depressurization valve; - a distribution manifold, connecting the lower discharge outlet of the vessel 20 and the introduction inlet of each depressurization tank, the distribution manifold being movable between a first configuration for distributing the pressurized flow rich in solid material to at least the first tank and depressurizing at least the second tank, in which the first tank is connected to the pressurized vessel, and the second tank is isolated from the pressurized vessel, and 25 a second configuration for distributing the pressurized flow rich in solid material toward at least the second tank and depressurizing at least the first tank, in which the second tank is connected to the pressurized vessel and the first tank is isolated from the pressurized vessel; wherein the pressurized fluid comprises a pressurized gas, the pressurized vessel comprising an upper outlet for discharging a flow rich in 30 pressurized gas.

The separator according to the invention can comprise one or several of the following features, considered alone or in any technically possible combinations: - the distribution manifold comprises an isolation valve of the first tank and an isolation valve of the second tank, Received at IPONZ 30 November 2011 3 and the separator comprises control means capable of moving the distribution manifold such that, in the first configuration, the isolation valve of the second tank is closed, the isolation valve of the first tank is open, and the depressurization valve of the first tank is closed, and in the second configuration, the isolation valve of the second tank is open, the isolation valve of the first tank is closed, and the depressurization valve of the first tank can be opened; - the distribution manifold comprises a moving cylinder having at least one distribution channel emerging upstream opposite the lower outlet for discharging the fluid rich in solid material, the cylinder being able to move in relation to the first tank and the second tank between a first position in the first configuration of the distribution manifold, in which the distribution channel is connected downstream of the first tank and is isolated from the second tank, and a second position in the second configuration of the distribution manifold, in which the distribution channel is connected downstream of the second tank and is isolated from the first tank; - the pressurized vessel is placed above each depressurization tank, the distribution manifold being inserted between the pressurized vessel and each tank; - the separator comprises at least a third depressurization tank and at least a fourth depressurization tank, the distribution manifold connecting, in its first configuration, the pressurized vessel to the first tank and to the third tank, and in its second configuration connecting the pressurized vessel to the second tank and to the fourth tank; and - it comprises means for reducing the speed of the solid material comprising deceleration means arranged opposite the injection inlet of the pressurized fluid into the pressurized vessel and protruding transversely in relation to the axis of circulation of the pressurized fluid in the injection inlet.

A second aspect of the invention provides a device for extracting a material situated at the bottom of an expanse of water, comprising: - a surface equipment at least partially arranged above the surface of the expanse of water; - a bottom assembly comprising means for withdrawing material on the bottom of the expanse of water; - a transport pipe connecting the bottom assembly to the surface equipment; and Received at IPONZ 30 November 2011 4 - a separator according to the first aspect, mounted on the surface equipment and connected to the transport pipe.

The device according to the invention can comprise the following feature: - the surface equipment comprises at least one compressor connected as outlet to a line for injecting pressurized fluid into the transport pipe, the discharge outlet for the pressurized fluid poor in solid material being connected to an inlet of the compressor.

A third aspect of the invention provides a method for continuous separation of a pressurized fluid using a separator according to the first aspect, the method comprising the continuous injection of the pressurized fluid into the pressurized vessel through the pressurized fluid injection inlet, and the formation in the pressurized vessel of a flow rich in solid material and at least one flow poor in solid material, wherein the method comprises, sequentially: - a plurality of distribution phases of the flow rich in solid material into at least the first depressurization tank, in which the distribution manifold occupies its first configuration, the pressure prevailing in the first tank being substantially equal to the pressure prevailing in the pressurized vessel; - a plurality of depressurization phases of the first tank, in which the distribution manifold occupies its second configuration, the pressure prevailing in the first tank being lower than the pressure prevailing in the pressurized vessel and in the second tank, the flow rich in solid material being distributed in the second tank.

The term 'comprising' as used in this specification and claims means 'consisting at least in part of. When interpreting statements in this specification and claims which include the term 'comprising', other features besides the features prefaced by this term in each statement can also be present. Related terms such as 'comprise' and 'comprised' are to be interpreted in similar manner.

Received at IPONZ 30 November 2011 The invention will be better understood from the following description, provided solely as an example, and done in reference to the appended drawings, in which: - Figure 1 is a diagrammatic side view of a first extraction device according to 5 the invention, provided with a continuous separator; - Figure 2 is a partially diagrammatic perspective view of the separator of the extraction device of Figure 1; - Figure 3 is a top view of the separator illustrated in Figure 2; - Figure 4 is a cross-sectional view along a middle vertical plane of the 10 separator of figure 2 in a first separating configuration; and - Figure 5 is a view similar to Figure 4 in a second separating configuration.

In the rest of this document, the terms "upstream" and "downstream" refer to the normal direction of circulation of a fluid.

A first extraction device 10 comprising a separator according to the invention 15 is illustrated in Figures 1 to 5.

This device 10 is intended to withdraw the solid materials situated at the bottom of an expanse of water 12 such as a sea, ocean or lake.

The expanse of water 12 rests on a bottom 14 defined by a solid material comprising rocks and/or sediment.

The purpose of the extraction device 10 is for example to perform earthworking of the bottom 14 for the placement of hydrocarbon exploitation Received at IPONZ 30 November 2011 equipment, or to withdraw ores deposited on the bottom 14, for their subsequent exploitation on the surface 16 of the expanse of water 12.

The extraction device 10 is for example of the type described in French applications no. 07 56579 and no. 07 56718 by the Applicant.

The extraction device 10 thus comprises surface equipment 18 supported by a floating assembly 20 on the expanse of water, a bottom assembly 22 for withdrawing solid material on the bottom 14 of the expanse of water 12, and a transport pipe 24 to convey the withdrawn material from the bottom assembly 22 toward the surface equipment 18. The device 10 also comprises operational lines 26 extending into the 10 expense of water 12 along the transport pipe 24 from the surface equipment 18.

The floating assembly 20 is formed by a ship or barge. Alternatively, it is formed by a platform floating on the expanse of water.

The bottom assembly 22 comprises a base station 28 fixed to the lower end of the pipe 24, means 30 for withdrawing material on the bottom 14, and a flexible pipe 15 32 for conveying the withdrawn material from the withdrawal means 30 toward the base station 28.

The withdrawal means 30 is for example supported by an excavator vehicle moving on the bottom 14.

Alternatively, the withdrawal means 30 comprises a crane actuated from the 20 floating assembly 20 and a support for receiving and treating the material, the support being placed on the bottom 14.

The transport pipe 24 extends between the base station 28 situated near the bottom 14 and the surface equipment 18 situated on the floating assembly 20. The length of the pipe, considered between the surface equipment 18 and the bottom 25 assembly 28, is for example between a few meters and more than 1000 m.

The transport pipe 24 is for example formed by an assembly of rigid tubes. Alternatively, it is formed by a pipe flexible over substantially its entire length.

The flexible connection 32 and the transport pipe 24 define an interior continuous passage 34 for the circulation of solid material, mixed with water between 30 the withdrawal means 30 on the bottom of the expanse of water and the surface equipment 18.

The operational lines 26 comprise a line 36 for injecting gas into the circulation passage 34 and electrical power and control lines 38 of the withdrawal means 30.

Received at IPONZ 30 November 2011 6 In the example illustrated in Figure 1, the mixture of water and solid material in the passage 34 is driven from the bottom 14 toward the surface equipment 18 by gas lift.

To that end, the line 36 extends between the surface equipment 18 and an 5 intermediate point 40 of the transport pipe 24 to inject pressurized gas into the passage 34 at the intermediate point 40. The pressure of the injected gas is higher than the atmospheric pressure, and for example between 10 bars and 100 bars.

Thus, the gas injection at point 40 forms, downstream of said point 40 in the passage 34, a pressurized fluid containing the divided solid material, the liquid water 10 and the pressurized gas. This pressurized fluid is lightened in relation to the fluid situated under the point 40, which causes said fluid to be driven upward.

As illustrated in Figure 1, the surface equipment 18 comprises a separator 50 according to the invention, connected to an upper end downstream of the transport pipe 28, and a vessel 52 for storing the solid material at atmospheric pressure, 15 hydraulically connected to the separator 50. The surface equipment 18 also comprises a compressor 54 for supplying the gas injection line 36 and control and electrical power means 56 for supplying the lines 38.

The separator 50 is intended to separate the pressurized fluid continuously received from the pipe 24, to form a flow rich in solid material in order to depressurize 20 it, and to form a gas flow poor in solid material formed by the gas present in the pressurized fluid to recover said gas without substantial decompression in order to reinject it into the compressor 54. Moreover, the separator 50 produces a liquid flow poor in solid material from the pressurized fluid, said flow being formed by the pressurized water present in the fluid.

The flow rich in solid material is formed by practically all of the agglomerated divided solid material and by the water present in the spaces between the bits of solid material.

As illustrated by Figures 1 to 5, the separator 50 comprises a speed reducer 60 for the solid material contained in the pressurized fluid, a pressurized vessel 62 30 for continuously receiving the pressurized fluid to obtain the flow rich in solid material, the liquid flow, and the gas flow.

The separator 50 also comprises a plurality of tanks 64 for recovering and depressurizing the flow rich in solid material, a selective distribution manifold 66 for Received at IPONZ 30 November 2011 7 sending the flow rich in solid material into the tanks 64, and means 68 for controlling the distribution manifold.

The pressurized vessel 62, the distribution manifold 66 and the depressurization tanks 64 are mounted from top to bottom on a chassis 74 provided 5 on a platform 76 of the floating assembly 20.

The vessel 62 comprises a lower wall 78 in the form of a hopper, a substantially cylindrical intermediate wall 80 with a vertical axis B-B', and an upper covering wall in the form of a tapered cone 82.

The walls 78, 80, 82 define a closed inner volume 84 for receiving the 10 pressurized fluid, intended to be kept at a pressure higher than the atmospheric pressure by the pressurized fluid.

The vessel 62 also comprises an upstream inlet 86 for injecting pressurized fluid into the volume 84, a downstream outlet 88 for discharging the flow of pressurized water outside the volume 84, an upper outlet 90 for discharging the flow 15 of pressurized gas outside the volume 84, and a lower outlet 92 for discharging the flow rich in solid material outside the volume 84.

The upstream inlet 86 and the downstream outlet 88 are formed horizontally in the intermediate wall 80 of the vessel 62, opposite each other.

The injection inlet 86 is connected to the transport pipe 24. 20 The pressurized water discharge outlet 88 is provided with a filtering grate 93 and a pressure regulator 94 in the inner volume 84. It is connected, downstream of the regulator 94, to pressurized water storage 96, or alternatively to means for depressurizing the water, if the water needs to be recovered at atmospheric pressure, for example to wash the solid material present or conveyed in the storage 25 tubs 52.

The upper gas discharge outlet 90 is connected to the compressor 54 by a pressurized gas supply pipe 98.

The lower outlet 92 is defined at the lower end of the lower wall 78. It has a substantially circular section and emerges opposite the distribution manifold 66. 30 The speed reducer 60 is placed in the vessel 62, opposite the injection inlet 86. It comprises transverse members 99 for slowing the solid material that protrude in the inner volume 84, perpendicular to the horizontal axis A-A' for injecting pressurized fluid through the inlet 86.

Received at IPONZ 30 November 2011 8 In the example illustrated in Figure 2, the transverse members 99 are formed by a curtain of chains or bars fixed at their upper end on the upper wall 82.

The reducer 60 decreases the speed of the solid material in the pressurized fluid to prevent damage to the walls of the vessel 62 during the injection of 5 pressurized fluid.

The depressurization tanks 64 are distributed around the vertical central axis A-A' of the receiving vessel 62.

In the example illustrated in Figure 2, the separator 50 comprises four tanks 64A to 64D with identical structures, arranged vertically around the axis B-B' under 10 the vessel 62 and under the distribution manifold 66.

Each tank 64A to 64D is generally cylindrical with a vertical axis parallel to axis B-B'.

Each tank 64A to 64D thus comprises an upper covering wall 100, with a vertical section converging upwardly, an intermediate cylindrical wall 102, and a 15 lower wall 104 with a section converging downwardly.

The walls 100, 102 and 104 define a closed inner space 105.

It also comprises an inlet 106 for introducing part of a flow rich in solid material in the space 105, formed at the apex of the upper wall 100, and an outlet 108 for depressurization and discharge of the fluid rich in solid material outside the space 20 105, formed in the bottom of the lower wall 104.

The introduction inlet 106 emerges vertically under the distribution manifold 66.

The depressurization outlet 108 emerges toward the bottom under the inlet 25 106. It is provided with a depressurization valve 110 that can be moved between an opening configuration allowing solid material to circulate through the outlet 108 and a closing configuration preventing solid material from circulating through the opening 108.

The outlet 108 is connected to a region subjected to atmospheric pressure, in 30 this example formed by the vessel 52 for storing the depressurized solid material at atmospheric pressure.

The depressurization valve 110 is connected to the control means 68 to be moved.

Received at IPONZ 30 November 2011 9 The distribution manifold 66 comprises, for each tank 64A to 64D, an individual supply line 116A to 116D, a rotary cylinder 118 for distributing the flow rich in solid material in the individual lines 116A to 116D, rotatably mounted in a cylindrical support 120.

Each individual supply line 116A to 116D extends between an upper opening 122 situated opposite the cylinder 118 and a lower opening 124 provided with an isolation valve of the tank 126A to 126D, connected to the introduction inlet 106 of the tank 64A to 64D. Each line 116A to 116B connects the cylinder 118 exclusively to a respective tank 64A to 64D.

Each valve 126A to 126D can be moved gradually between a completely open configuration, in which the individual line 116A to 116D is connected to the related tank 64A to 64D, and a completely closed configuration in which the tank 64A to 64D is isolated from the line 116A to 116D.

Each valve 126A to 126D is connected to the control means 68 to be moved. 15 The support 120 extends under the vessel 62 in the lower extension of the lower outlet 92.

The cylinder 118 is rotatably mounted around the vertical axis B-B' in the support 120. It comprises two funnels 130 arranged side by side on either side of a vertical plane passing through the axis B-B'.

Each funnel 130 defines a channel 131 emerging upstream opposite the lower outlet 92 and able to emerge downstream exclusively opposite the upper opening 122 of a line 116A to116D.

The cylinder 118 can thus rotate around the axis B-B' between a first position supplying the first tank 64A and the second tank 64C and isolating the second tank 25 64B and the fourth tank 64D, and a second position supplying the second tank 64B and the fourth tank 64D and isolating the first tank 64A and the second tank 64C.

In the first position illustrated in figure 4, the funnels 130 emerge upstream toward the top opposite the outlet 92, and downstream toward the bottom opposite the upper openings 122 of the supply lines 116A, 116C of the first tank 64A and third 30 tank 64C, respectively.

The funnels 130 also mask the upper openings 122 in the supply lines 116B, 116D of the second tank 64B and the fourth tank 64D.

Thus, in the first position of the cylinder 118, the flow rich in solid material can flow from the inner volume 84 toward the first tank 64A and toward the third tank 64C Received at IPONZ 30 November 2011 through the funnels 130, the individual lines 116A, 116C, and the valves 126A, 126C, successively.

In this position, the cylinder 118 prevents the flow rich in solid material from circulating from the inner volume 84 toward the second tank 64B and the fourth tank 5 64D.

On the contrary, in the second position illustrated in Figure 5, the cylinder 118 has pivoted about 90° around the axis B-B'. The funnels 130 are arranged opposite upper openings 122 of the individual lines 116B, 116D allowing the flow rich in solid material to flow from the inner volume 84 toward the second tank 64B and toward the 10 fourth tank 64D through the funnels 130, the individual supply lines 116B, 116D and the valves 126B, 126D.

Moreover, as shown in Figure 5, the funnels 130 mask the openings 122 of the individual supply lines 116A, 116C of the tanks 64A, 64C, which prevents the flow rich in solid material from circulating from the volume 84 toward said tanks 64C, 64C. 15 The control means 68 comprises means for moving the cylinder 118 between its first position and its second position, means for controlling the isolation valves 126A to 126D of each supply line 116A to 116B, and means for controlling the depressurization valves 110 of each tank 64A to 64D.

They also comprise, for each tank 64A to 64D, a probe 132 measuring the 20 pressure in that tank 64A to 64D, and a probe 134 measuring the level of material contained in the tank 64A to 64D.

The control means 68 can move the distribution manifold 66 between a first configuration for distributing the flow rich in solid material in the tanks 64A, 64C and depressurizing the tanks 64B, 64D, and a second configuration for distributing the 25 flow rich in solid material in the tanks 64B, 64D and depressurizing the tanks 64A, 64C.

In the first configuration, the control means 68 move the cylinder 118 to place it in its first position described above. Moreover, they move the valves 126A, 126C of the individual lines 116A, 116C to keep them open, and the closure valves 110 of the 30 tanks 64A, 64C to keep them closed. The pressure that then prevails in the inner spaces 105 of the first and third tanks 64A, 64C is substantially identical to the pressure that prevails in the inner volume 84 of the receiving vessel 62.

Moreover, the control means 68 moves the valves 124B, 124D of the individual lines 116B, 116D to isolate the second tank 64D and the fourth tank 64B of Received at IPONZ 30 November 2011 11 the distribution manifold 66 and the vessel 62. They can also move the depressurization valves 110 of said tanks 64B, 64D to gradually depressurize the flow rich in solid material and discharge it from the tanks 64B, 64D toward the vessel 52.

On the contrary, in the second configuration, the control means 68 moves the cylinder 118 to place it in its second position described above. It also moves the valves 126B, 126D of the individual lines 116B, 116D to keep them open, and the closure valves 110 of the tanks 64B, 64D to keep them closed. The pressure that then prevails in the inner spaces 105 of the second and fourth tanks 64B, 64D is 10 substantially identical to the pressure that prevails in the inner volume 84 of the receiving vessel 62.

Moreover, the control means 68 moves the valves 124A, 124C of the individual lines 116A, 116C to isolate the first tank 64A and the third tank 64C of the distribution manifold 66 and the vessel 62. The means 68 can also move the 15 depressurization valves 110 of these tanks 64A, 64C to gradually depressurize the flow rich in solid material and discharge it from the first and third tanks 64A, 64C toward the vessel 52.

The operating method of the extraction device 10 will now be described.

Initially, the transport pipe 26 and the bottom assembly 22 are lowered into the 20 expanse of water 12 until the withdrawal means 30 is placed in contact with the bottom 14.

The control means 56 then activates the withdrawal means 30 via lines 38 and orients them on the bottom 14 of the expanse of water to withdraw solid material.

A flow of mixture formed by a mixture of divided solid material and liquid water 25 is conveyed through the circulation passage 34 in the flexible pipe 32 and in the transport pipe 26.

To drive the flow of mixture thus formed upwards, gas pressurized at between 10 bars and 100 bars from the compressor 54 is injected through the gas injection line 36 at the intermediate point 40. The flow of mixture then forms a pressurized fluid 30 containing the divided solid material, the liquid water and the injected gas.

This pressurized fluid then rises toward the surface equipment 18 and continuously enters the inner volume 84 of the tank 62, where it passes through the decelerator 60 situated opposite the inlet 86.

Received at IPONZ 30 November 2011 12 The divided solid material present in the pressurized fluid comes into contact with transverse members 99, which decreases their speed along the horizontal injection axis A-A' in the pressurized vessel 62. Thus, the risk of deterioration of the vessel 62 is decreased.

In the volume 84, the solid material is driven downward by gravity, which creates, opposite the lower wall 78, a flow rich in solid material, opposite the intermediate wall 80, a flow rich in liquid water, and opposite the wall 82, a gaseous flow.

The outlet 88 being provided with the filtering grate 93, the flow rich in liquid is substantially purged of the solid material it contains and is continuously discharged through the downstream outlet 88 via the pressure regulator 94 to the pressurized liquid source 96.

Alternatively, the liquid flow is depressurized and the water at atmospheric pressure is used to wash the material rich in solid withdrawn from the tanks 64.

Likewise, the gaseous flow is continuously discharged toward the top through the gas discharge outlet 90 to feed the compressor through the pipe 98.

The pressure prevailing in the inner volume 84 defined by the vessel 62 is substantially equal to the pressure of the fluid, for example between 8 bars and 15 bars. The gas discharged through the upper outlet 98 thus has a pressure higher than the atmospheric pressure, for example between 8 bars and 12 bars. Thus, the size of the compressor 54 present on the floating assembly can be decreased, which limits its cost. Likewise, the water discharged through the downstream outlet 88 has a pressure between 6 bars and 10 bars.

The distribution manifold 66 is then moved by the control means 68 so that it is in its first configuration described above.

In the first configuration, the flow rich in solid material flows by gravity through the lower discharge outlet 92, the funnels 130 and the individual supply lines 116A, 116C of the first tank 64A and the second tank 64C to fill said tanks 64A, 64C.

Simultaneously, the second tank 64B and the fourth tank 64D are emptied to discharge their content toward the vessels 52 while keeping the corresponding isolation valves 126B, 126D closed.

When the emptying of the tanks 64B, 64D is finished, the control means 68 then close the depressurization valves 110 of the second tank 64D and the fourth tank 64D while gradually freeing the isolation valves 126B, 126D of said tanks in Received at IPONZ 30 November 2011 13 order to gradually bring the inner spaces 105 of the tanks 64B, 64D to the pressure prevailing in the volume 84.

When the level detecting means 134 detect that the tanks 64A and 64C are substantially full, the distribution manifold 66 is moved by the control means 68 to go 5 from its first distribution configuration to its second distribution configuration.

The isolation valves 126A, 126C of the tanks 64A, 64C are then closed and the cylinder 118 is pivoted from its first position to its second position. The isolation valves 126B, 126D of the second tank 64D and fourth tank 64D are then completely opened to receive the flow rich in solid material.

Simultaneously, the depressurization valves 110 of the first tank 64A and the third tank 64C are gradually opened to discharge the flow rich in solid material from each tank 64A, 64C toward the vessel 62 and depressurize it.

The pressure that then prevails in the inner spaces 105 of the tanks 64A, 64C is lower than the pressure that prevails in the inner volume 84 of the receiving vessel 15 62, and is substantially equal to the atmospheric pressure.

Then, as previously described, the depressurization valves 110 of the tanks 64A, 64C are closed, and the isolation valves 126A, 126C of the tanks 64A, 64C are gradually opened to gradually pressurize the tanks 64A, 64C, the pressure being monitored by the probes 132.

The separator 50 therefore allows the continuous treatment of the pressurized fluid containing gas, liquid water and solid material conveyed by the pipe 24 while keeping it pressurized in the vessel 62.

The separator 50 also allows the depressurization of a flow rich in solid material formed in the pressurized vessel 62. This depressurization is done 25 sequentially in the various retention tanks 64A to 64D, without having to depressurize the receiving vessel 62.

It is therefore possible, using the separator 50 according to the invention, to recycle the gaseous flow and the pressurized liquid flow recovered at the outlet of the pressurized vessel 62, to reuse them in the extraction device 10, while recovering the 30 solid material at atmospheric pressure for storage thereof.

Alternatively, the distribution manifold 66 comprises means for declogging each funnel 30 of the cylinder 118 and/or each individual line 116A to 116D. This declogging means is for example made up by jets of pressurized water.

Received at IPONZ 30 November 2011 14 In another alternative, the flow of mixture containing solid material and water is conveyed upward in the passage 34 of the transport pipe 34 by injecting pressurized liquid into the passage.

In this case, the pressurized liquid is at least partially produced from the flow 5 of pressurized liquid recovered at the downstream discharge outlet 88 of the vessel 62.

In another alternative, the outlets 108 of the tanks 64 emerge opposite at least one conveyor belt to receive and move the recovered solid material toward a lateral edge of the floating assembly and load it on a transport barge situated opposite the 10 lateral edge.

Claims

Received at IPONZ 30 November 2011 15 What we claim is :

1. A separator for continuously receiving a pressurized fluid, the pressurized 5 fluid containing at least one divided solid material and one liquid, the separator being of the type comprising: - a pressurized vessel for separating the pressurized fluid into a flow rich in solid material, and into at least one pressurized flow poor in solid material, the pressurized vessel comprising a pressurized fluid injection inlet, a lower discharge 10 outlet for the pressurized flow rich in solid material, and at least one discharge outlet of the or each pressurized flow poor in solid material, wherein the separator comprises: - at least one first and one second tank for depressurizing a pressurized flow rich in solid material, each tank defining a closed inner space emerging through an 15 inlet for introducing the pressurized flow rich in solid material and through a depressurization outlet, provided with a depressurization valve; - a distribution manifold, connecting the lower discharge outlet of the vessel and the introduction inlet of each depressurization tank, the distribution manifold being movable between a first configuration for 20 distributing the pressurized flow rich in solid material to at least the first tank and depressurizing at least the second tank, in which the first tank is connected to the pressurized vessel, and the second tank is isolated from the pressurized vessel, and a second configuration for distributing the pressurized flow rich in solid material toward at least the second tank and depressurizing at least the first tank, in which the 25 second tank is connected to the pressurized vessel and the first tank is isolated from the pressurized vessel; wherein the pressurized fluid comprises a pressurized gas, the pressurized vessel comprising an upper outlet for discharging a flow rich in pressurized gas.

2. The separator according to claim 1, characterized in that the distribution 30 manifold comprises an isolation valve, of the first tank and an isolation valve of the second tank, and in that the separator comprises control means capable of moving the distribution manifold such that, in the first configuration, the isolation valve of the Received at IPONZ 30 November 2011 16 second tank is closed, the isolation valve of the first tank is open, and the depressurization valve of the first tank is closed, and such that in the second configuration, the isolation valve of the second tank is open, the isolation valve of the first tank is closed, and the depressurization 5 valve of the first tank can be opened.

3. The separator according to any one of the preceding claims, characterized in that the distribution manifold comprises a moving cylinder having at least one distribution channel emerging upstream opposite the lower outlet for discharging the fluid rich in solid material, the cylinder being able to move in relation to the first tank 10 and the second tank between a first position in the first configuration of the distribution manifold, in which the distribution channel is connected downstream of the first tank and is isolated from the second tank, and a second position in the second configuration of the distribution manifold, in which the distribution channel is connected downstream of the second tank and is isolated from the first tank. 15

4. The separator according to claim 3, characterized in that the cylinder is mounted rotatably mobile around a substantially vertical axis.

5. The separator according to any one of the preceding claims, characterized in that the pressurized vessel is placed above each depressurization tank, the distribution manifold being inserted between the pressurized vessel and each tank. 20

6. The separator according to any one of the preceding claims, characterized in that it comprises at least a third depressurization tank and at least a fourth depressurization tank, the distribution manifold connecting, in its first configuration, the pressurized vessel to the first tank and to the third tank, and in its second configuration connecting the pressurized vessel to the second tank and to the fourth 25 tank.

7. The separator according to any one of the preceding claims, characterized in that it comprises means for reducing the speed of the solid material comprising deceleration members arranged opposite the injection inlet of the pressurized fluid into the pressurized vessel and protruding transversely in relation to an axis of 30 circulation of the pressurized fluid in the injection inlet.

8. A device for extracting a material situated at the bottom of an expanse of water, comprising: - a surface equipment at least partially arranged above the surface of the expanse of water; Received at IPONZ 30 November 2011 17 - a bottom assembly comprising means for withdrawing material on the bottom of the expanse of water; - a transport pipe connecting the bottom assembly to the surface equipment and 5 - a separator as defined in any one of the preceding claims, mounted on the surface equipment and connected to the transport pipe.

9. The device according to claim 8, characterized in that the surface equipment comprises at least one compressor connected as outlet to a line for injecting pressurized fluid into the transport pipe, the discharge outlet for the 10 pressurized fluid poor in solid material being connected to an inlet of the compressor.

10. A method for continuous separation of a pressurized fluid using a separator according to any one of claims 1 to 7, the method comprising the continuous injection of the pressurized fluid into the pressurized vessel through the pressurized fluid injection inlet, and the formation in the pressurized vessel of a flow 15 rich in solid material and at least one flow poor in solid material, wherein the method comprises, sequentially: - a plurality of distribution phases of the flow rich in solid material into at least the first depressurization tank, in which the distribution manifold occupies its first configuration, the pressure prevailing in the first tank being substantially equal to the 20 pressure prevailing in the pressurized vessel; - a plurality of depressurization phases of the first tank, in which the distribution manifold occupies its second configuration, the pressure prevailing in the first tank being lower than the pressure prevailing in the pressurized vessel and in the second tank, the flow rich in solid material being distributed in the second tank. 25

11. The separator according to claim 1, substantially as herein described with reference to any embodiment disclosed.

12. A separator for continuously receiving a pressurized fluid substantially as herein described with reference to any embodiment shown in the accompanying drawings. 30

13. The device according to claim 8, substantially as herein described with reference to any embodiment disclosed.

14. A device for extracting material situated at the bottom of an expanse of water substantially as herein described with reference to any embodiment shown in the accompanying drawings. Received at IPONZ 30 November 2011 18

15. The method according to claim 10, substantially as herein described with reference to any embodiment disclosed.