The present disclosure concerns an underwater hydrocarbon processing facility.
In particular, the present disclosure concerns an underwater hydrocarbon processing facility configured to process fluids deriving from the hydrocarbon extraction from underwater wells. The underwater processing facilities can be located either relatively close to the underwater wells or to the topside or in intermediate locations. Further, the underwater hydrocarbon processing facility can be set on a bed of body of water in different locations along the bed depending on the selected underwater field development scheme.
The concept of underwater hydrocarbon processing facilities has been developed by different operators with the aim of streamlining the production of hydrocarbon from underwater wells. In general, the underwater hydrocarbon processing facility is part of a plant including topside hydrocarbon processing facilities, and long distance transport pipelines. The exploitation of underwater oil and/or gas hydrocarbon reservoirs, through underwater hydrocarbon processing facilities, foreseeing the collection and transport of the hydrocarbon up to topside facilities or to shore, is known. The development of underwater hydrocarbon processing facilities has rapidly increased in recent years and it is likely to boom in the near future. These underwater hydrocarbon processing facilities can be located from shallow to deepwater and in any geographical areas of the world in mild or harsh environment. The topside facilities can be located on offshore fixed or floating vessels or onshore and that can be relatively near, relatively far or relatively very far from the reservoir. The underwater field development schemes/configurations have become more complex because of the increasing number of requirements and by the need of reducing the project development costs to make the exploitation of the fields economically attractive. This issue is even more important in deepwater and/or when the topside facilities are relatively far or relatively very far from the field.
The recent developments of underwater technology processing devices and the great interest of oil companies boosted the feasibility of complex schemes. For examples, the recent development of underwater active processing devices broadens the potentiality of the underwater hydrocarbon processing facilities to cover nearly all the processes of a plant. The active underwater processing devices are configured to perform the following activities: boosting the hydrocarbon (single or multiphase), separation or water treatment or combination of these processes. Consequently the main underwater processing activities are the following: liquid boosting, multiphase boosting, underwater separations (liquid/liquid, Gas/liquid, oil/water/gas), wet or dry gas boosting, water treatment, heat exchange and injection. Prototypes of underwater processing devices were designed and built since the 1970's but the first industrial applications were performed in the 1990's starting with single phase and multiphase subsea pumps. In the 2000's the first subsea separation station was installed in the North Sea. However, underwater processing devices still have limited Mean Time Between Maintenance (MTBM) and require frequent intervention. Moreover, underwater hydrocarbon processing facilities have to be adapted to the evolution of the field because the process parameters change during the field life. Adaption means changing and/or expanding the production rate of the underwater hydrocarbon processing facilities that shall be configured to fulfill also this need. The oil companies exploiting the fields have the goals of increasing the production uptime and reducing the lifecycle costs (CAPEX+OPEX).
Additional information on the current status of underwater hydrocarbon processing facilities can be found in the OTC 24307 paper “STEPS TO SUBSEA FACTORY” by Rune Mode Ramberg (Statoil), Simon R. H. Davies (Statoil), Hege Rognoe (Statoil), Ole Oekland (Statoil).
Many advantages correlated to underwater hydrocarbon processing facilities are listed in the above-reference paper that, among others, includes:
While underwater hydrocarbon processing facilities bring many great advantages, the downsides are that the construction and the maintenance of an underwater hydrocarbon processing facility are rather complex with a degree of complexity that increases with the water depth or with the peculiar characteristics of the hydrocarbon field. The underwater hydrocarbon processing facilities are currently configured and built in accordance to two types of architecture: the single block architecture, and the multiple blocks architecture. The underwater hydrocarbon processing facilities organized according to the single block architecture have the drawback of being relatively heavy and each processing device is hardly replaceable by an analogous device. The underwater hydrocarbon processing facilities organized according to the multiple blocks architecture, such as that disclosed in U.S. Pat. No. 6,640,901, call instead for a large number of connections between blocks and the interfaces between blocks and are thus rather relatively complicated.
In addition to that, both architectures do not offer an adequate flexibility for relatively easily adapting the underwater hydrocarbon processing facility to different demands. Furthermore, installation, inspection, maintenance and retrieval of blocks can be particularly relatively demanding tasks.
It is an advantage of the present disclosure to provide an underwater hydrocarbon processing facility that mitigates certain of the drawbacks of certain of the prior art.
According to the present disclosure there is provided an underwater hydrocarbon processing facility, the facility comprising at least one cluster configured to process the process fluids including liquids and/or gases deriving from hydrocarbon extraction process, the cluster comprising:
In other words, the process fluids flow in and out the cluster through the interconnection unit only. The interconnecting unit can also interface directly with manifolds, or underwater well equipment like X-mas trees.
The interconnection unit according to the present disclosure provides many advantages: it permits arranging an underwater hydrocarbon processing facility in accordance to a new type of architecture that, is at the same time relatively compact and allows flexibility; it renders relative easy operatively coupling the first and second connection members to the benefits of the relative quick interchangeability of modules; and enhance standardization of interfaces between first and second connection members. At the same time, the interconnection unit according to the present disclosure allows a significant optimization and reduction of interfaces, integrates manifolding functions including inlet and outlet facilities and any non-critical pipework outside the standard modules, and it can be relatively conveniently tested onshore before deployment.
In view of the above, the interconnection unit favors the modularization of and helps in reducing modules dimensions and weights. De facto, the interconnection unit is the sole part of the cluster that is customized to the need of a designated or given gas/oil field and allows interconnecting several modules performing different processes or even the same process. When at least two modules perform the same process, these modules operate in parallel or in series and are interconnected in parallel or in series, as required, by the interconnection unit.
If, on the one side, the interconnection unit has a substantially passive function of conveying process fluids, chemicals, and possibly hydraulic fluids, on the other side, has an active function in controlling the modules that are connected to the same interconnection unit.
In particular, each module hosts one processing device selected from the following fluid processing devices:
In practice, any processing device can be standardized in function and even in size to enable interchangeability.
In particular, the interconnection unit houses a plurality of first pipes, each one extending at least from one second connection member to another second connection member and configured to operatively convey the process fluids between modules.
In other words, the interconnection unit has the function of operatively and fluidically connecting the modules hosting the respective processing devices and in performing this function is a substantially passive block.
In particular, each module comprises a first frame housing the respective processing device, and the interconnection unit comprises a second frame larger than the first frame so as to enable simultaneously arranging of the interconnection unit in a face to face configuration with a plurality of modules.
According to the present disclosure the processing devices and the pipes are supported and housed in respective first and second frames, which to certain extent protects the processing device and the pipes.
In particular, the first and the second frames are open frames and are configured as a parallelepiped, in particular as a rectangular parallelepiped.
The parallelepiped shapes of interconnection unit and modules enable combining them as building blocks and arranging them in side by side configuration and render possible retrieving the modules and, if foreseen and necessary, the interconnection unit. Alternatively the building blocks can be also interfaced on top of the interconnection unit.
In addition to that, the first and the second frames are configured to be directly or indirectly mechanically coupled to one another.
The mechanical coupling of frames defines a precise spatial relationship between first and second frame so that it possible to define a layout of first and second connection members beforehand.
In particular, the interconnection unit comprises a platform, which stably supports the second frame and is configured to guide each one of the first frames, when lowered on the platform, in a designated or given position on a side of the second frame and in close proximity to the second frame so as to align each first connection member to a second corresponding connection member; the first and second connection members projecting from the facing lateral side of the respective first and second frames.
The platform is relatively stable and defines an even support for the first and second frames. According to this connection method the module is lowered in close proximity of the second frame.
According to another connection method, the interconnection unit comprises a sledge configured to slide on the platform towards and away from the second frame; the sledge being configured to guide one of the first frames, when lowered on the sledge, in a designated or given position on a side of the second frame so as to align each first connection member to a corresponding second connection member; the first and second connection members projecting from the facing lateral side of the respective first and second frames.
This connection method requires lowering the module and displacing the module towards the second frame.
Another connection method consists in lowering the module on top of the second frame of the interconnection unit. In this case the second frame is configured to support the first frame located on top of the second frame and to guide the first frame, when lowered on the second frame, in a designated or given position on top of the second frame so as to align each first connection member to a corresponding second connection member; the first and second connection members projecting from the facing bottom face and top face of the respective first and second frames.
Irrespective of the connection method the mechanical coupling is, in certain embodiments, achieved by mutually engaging guide posts and guide engaging members. In particular, the interconnection unit comprises the guide posts, whereas each second frames comprises guide engaging members, in particular guide funnels, configured to mechanically couple the first frame to the interconnection unit.
In particular, the first connection members are arranged along a first face of the first frame in accordance to a designated or given interface layout matching with a designated or given interface layout of the second connection members in the second frame.
This arrangement of interface layouts of the first and second connection members for the process fluids renders relatively easier the connection and enhances standardization.
In particular, the interconnection unit comprises a plurality of control cables and a quantity or number of junction plates configured to connect the control cables to the modules.
The interconnection unit can relatively conveniently have the additional function of exchanging control signals with each module with the advantage of relatively simplifying the connections of control cables.
In particular, the interconnection unit comprises a plurality of tubes configured to convey chemicals and/or hydraulic fluids and a quantity or number of junction plates configured to connect the tubes to the modules.
Chemicals are often used in the processes of a hydrocarbon processing facility, whereas hydraulic fluids are sometimes optional and are used for actuating and controlling the modules. According to the present disclosure, the distribution of chemicals and the hydraulic fluids to the modules can be conveniently accomplished by the interconnection unit.
In particular, the junction plate comprises a quantity or number of electrical connectors connected to a corresponding quantity or number of control cables; and a number of tube connectors connected to a quantity or number of tubes.
Conveniently, junction plates can enhance standardization.
In particular, the subsea control module is further connected to an umbilical in order to exchange information with a surface control station.
According to a particular aspect of the present disclosure, each module comprises a further subsea control module configured to control parameters correlated to the respective process. The further subsea control module operates as a slave. The function of master can be performed by the subsea control module of the interconnection unit or by a surface control station.
Additional features and advantages are described in, and will be apparent from the following Detailed Description and the figures.
A number of non-limiting embodiments of the present disclosure will be described by way of example with reference to the attached drawings, in which:
Referring now to the example embodiments of the present disclosure illustrated in
In the example shown cluster 3b comprises three modules 4, 5, and 7, and the interconnection unit 8 which has been adapted for being connected with a lower quantity or number of modules.
Each one of the modules 4, 5, 6 and 7 houses one device configured to process the hydrocarbon or configured to perform operations correlated to hydrocarbon processing. In general, these devices (functional building blocks performing a single process function/task) include:
In the example disclosed in
The interconnection unit 8 comprises a plurality of pipes 13, each extending between a couple of connection members 10, and valves 14 configured to adapt the interconnection unit 8 to operate with different quantities or numbers of modules.
With reference to
The description of module 4 in
With reference to
In general, each module 4 has at least two connection members 9 arranged along the same face: a connection member 9 that defines the inlet of a fluid to be processed and a connection member 9 that defines the outlet of a processed fluid. The process fluids can be either gases or liquids or both. Beside the basic configuration of modules with just two connection members 9, there are provided modules with several connection members 9 configured to process gases and liquids.
In accordance to the example shown in
Frame 18 is higher than frame 15 (
With reference to
For this purpose and with reference to Figures from 8 to 14, frames 15 and 18 are configured to be mechanically coupled to one another directly or indirectly in order to define designated or given relative spatial positions between frame 15 and frame 18 and to arrange a connection member 9 in front of a corresponding connection member 10 and in close proximity of the corresponding connection member 10.
In
When the module 4 is completely lowered onto platform 17 as shown in
The above-described connection method is applicable to all type of environment (mild/harsh).
In
In particular, this connection method is applicable for mild environment and deep-water projects (deeper than 1000 m) where there is no fishing interaction and limited risk of damaging the connections during the landing module 4.
Starting from a position in which sledge 30 is relatively remote from frame 15 (
In particular, this connection method is applicable only for smaller modules (below 70 T).
In particular module 34 houses a gas/liquid separation device, module 35 houses a liquid/liquid separation device, modules 36 house respective water injection pumps working in parallel, and modules 37 house respective multi-phase pumps working in parallel.
The interconnection unit 8 comprises a plurality of pipes 41 including one or more bifurcation configured to connect modules operating in parallel.
With reference to the embodiment of
Connection members 10 are interconnected by pipes (not shown in
The interconnection unit 48 is configured to distribute and collect signals, chemicals and hydraulic fluids to and from modules 44, 45, 46, and 47. Consequently, the interconnection unit 48 comprises a plurality of control cables 51; and a plurality of tubes 52 configured to convey chemicals and/or hydraulic fluids.
The interconnection unit 48 comprises a platform 53 which is configured to support the modules 44, 45, 46 and 47; two control distribution units 54; and two chemical distribution units 55.
Signals, chemicals, hydraulic fluids and electric power are conveyed through an umbilical 56 to an umbilical switching unit 57, which distributes the electric power directly through power cables 58 to modules 44 and 46 hosting powered processing devices such as pumps or compressors.
The umbilical switching unit 57 is connected to the two control distribution units 54 by a bundle of control cables 59 and a bundle 60 of tubes for hydraulic fluids; and to chemicals distribution units 55 by bundle 60 of tubes for chemicals.
The control distribution units 54 and the chemicals distribution units 55 are in turn connected to the interconnection unit 48.
The interconnection unit 48 disclosed in
Each one of the modules 44, 45, 46, 47 comprises a subsea control module 62 configured to control parameters correlated to the respective process.
In particular, the subsea control module 62 of the interconnection unit 48 has the function of master and is connected to all subsea control modules 62 installed in the modules 44, 45, 46, and 47. The subsea control modules 62 of the modules 44, 45, 46, and 47 have the function of slave with respect subsea control module 62 installed in the interconnection unit 48.
The entire supervision of the underwater hydrocarbon processing facility 42 is in any case performed by a surface control station (not shown in the Figures).
The electrical and fluid connection between interconnection 48 and modules 44, 45, 46, and 47 are achieved by junction plates 63 disclosed in
With reference to
Junction plates 63 can be arranged on the lateral side of the interconnection unit 48 or on the top of the same and are connected to junction plate 22 of
Also the modular construction of the facility 42 enables enhancing standardization of junction plate 22.
The additional functions described in connection with the interconnection unit 48 are applicable to any one of the interconnection units 8, 16, 38 previously described. In
Clearly, changes, not described herein, can be made to the present disclosure without, however, departing from the protective scope of the accompanying Claims. For example, junction plates include multibore connections. In another example, the subsea control module can be omitted from the interconnection unit and mounted outside from the interconnection unit, closely or remotely. According to another variation (not shown in the drawings) the subsea control module is retrievable. Accordingly, various changes and modifications to the presently disclosed embodiments will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.
Number | Date | Country | Kind |
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15154035.8 | Feb 2015 | EP | regional |
This application is a national stage application of PCT/IB2016/050605, filed on Feb. 5, 2016, which claims the benefit of and priority to EP Patent Application No. 15154035.8, filed on Feb. 5, 2015, the entire contents of which are each incorporated by reference herein.
Filing Document | Filing Date | Country | Kind |
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PCT/IB2016/050605 | 2/5/2016 | WO | 00 |