Abstract
The present invention relates to an apparatus for separation of high volume flows of mixtures provided with at least two immiscible phases, especially for the first separation steps of flows of water/oil/gas/sand mixture that enter the apparatus as a wellstream mixture. The invention also relates to a method for separation of high volume flows of mixtures provided with at least immiscible phases.
Claims
1. A separation apparatus for separation of volume flows of mixtures provided with at least two immiscible phases, comprising: a vessel provided with: an inlet for the mixture provided with the at least two immiscible phases; a separation interior; at least one heavy phase outlet for a separated heavy phase fraction located on a lower side of the vessel and being connected with a first subsequent separator located outside of the vessel and downstream of the heavy phase outlet, wherein the separated heavy phase fraction leaving the separator through the heavy phase outlet is fed to the first subsequent separator; a light phase outlet for a separated light phase fraction located above the heavy phase outlet and being connected with a second subsequent separator located outside of the vessel and downstream of the light phase outlet, wherein the separated light phase fraction leaving the vessel through the light phase outlet is fed to the second subsequent separator; wherein the vessel comprises at least one substantially spherical shaped casing to be designed for use under a higher external pressure than 1 atmosphere, and wherein at least one of the first or second subsequent separators is a compact separator, wherein the compact separator is selected from the group consisting of: centrifugal separators, cyclone separators, coalescers and vortex separators, and wherein in the separation interior of the vessel a vane diffuser comprising a plurality of vanes is connected to the inlet for enabling separation of the mixture.
2. The separation apparatus according to claim 1, wherein at the lower side of the vessel a solid particle outlet is provided.
3. The separation apparatus according to claim 1, wherein the apparatus is designed for use wherein the external pressure is higher than the internal pressure.
4. The separation apparatus according to claim 1, wherein the vessel comprises plural interconnected spherical shaped casings.
5. The separation apparatus according to claim 4, wherein the vessel comprises at least two stacked and interconnected spherical shaped casings.
6. The separation apparatus of claim 1, wherein the second separator contains a light phase outlet and a heavy phase outlet, where the heavy phase out of the second separator does not feed into the vessel.
7. The separation apparatus according to claim 1, wherein both the first and second subsequent separators are compact separators, wherein the compact separators are individually selected from the group consisting of: centrifugal separators, cyclone separators, coalescers and vortex separators.
8. The separation apparatus according to claim 1, wherein the separation apparatus is submerged underwater.
9. The separation apparatus according to claim 7, wherein the separation apparatus is located at the seabed.
10. A method for separation of volume flows of a wellstream mixture provided with at least two immiscible phases comprising the steps of: A) feeding a volume flow of the wellstream mixture to a vessel provided with at least one substantially spherical shaped casing and a separation interior having a vane diffuser connected to an inlet for enabling separation of the well stream mixture; B) pre-separating the wellstream mixture in the vessel; C) feeding a separated heavy phase fraction leaving the vessel to a first subsequent separator, D) feeding a separated light phase fraction leaving the vessel to a second subsequent separator, E) subsequent separation of the separated heavy phase fraction and the separated light phase fraction in the respective first and second subsequent separators, wherein at least one of the first or second subsequent separators is a compact separator selected from the group consisting of: centrifugal separators, cyclone separators, coalescers and vortex separators, wherein the method is performed in the apparatus of claim 1.
11. The separation method according to claim 10, wherein the subsequent separation processes of the separated heavy phase fraction and the separated light phase fraction both take place by through flow of the fractions through the subsequent separators.
12. The separation method according to claim 10, wherein the wellstream mixture is pre-separated in the vessel according step B) providing two different pre-separated wellstream fractions.
13. The separation method according to claim 10, wherein the separated light phase fraction leaving the vessel contains less than 40 volume % of liquid.
14. The separation method according to claim 13, wherein the separated light phase fraction leaving the vessel contains less than 30 volume % of liquid.
15. The separation method according to claim 14, wherein the separated light phase fraction leaving the vessel contains less than 20 volume % of liquid.
16. The separation method according to claim 10, wherein the separation apparatus is submerged underwater.
17. The separation method according to claim 16, wherein the separation apparatus is located at the seabed.
18. A separation apparatus for separation of volume flows of mixtures provided with at least two immiscible phases, comprising: a vessel provided with: an inlet for the mixture provided with the at least two immiscible phases; a separation interior; at least one heavy phase outlet for a separated heavy phase fraction located on a lower side of the vessel and being connected with a first subsequent separator located outside of the vessel and downstream of the heavy phase outlet, wherein the separated heavy phase fraction leaving the separator through the heavy phase outlet is fed to the first subsequent separator; a light phase outlet for a separated light phase fraction located above the heavy phase outlet and being connected with a second subsequent separator located outside of the vessel and downstream of the light phase outlet, wherein the separated light phase fraction leaving the vessel through the light phase outlet is fed to the second subsequent separator; wherein the vessel comprises at least one substantially spherical shaped casing to be designed for use under a higher external pressure than 1 atmosphere, and wherein at least one of the first or second subsequent separators is a compact separator, wherein the compact separator is selected from the group consisting of: centrifugal separators, cyclone separators, coalescers and vortex separators, wherein in the separation interior of the vessel a vane diffuser comprising a plurality of vanes is connected to the inlet for enabling separation of the mixture, and wherein both the first and second subsequent separators are compact separators, wherein the compact separators are individually selected from the group consisting of: centrifugal separators, cyclone separators, coalescers and vortex separators.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The invention is further elucidated on the basis of the non-limitative exemplary embodiments shown in the following figures. Herein:
(2) FIG. 1A shows a schematically represented a part of a first embodiment of the separation apparatus according the present invention;
(3) FIG. 1B shows schematically represented the full embodiment of the separation apparatus as already partially presented in FIG. 1A, now with additional subsequent in-line processing equipment;
(4) FIG. 1C shows schematically represented the full embodiment of the separation apparatus as partially presented in FIG. 1A with a second alternative additional processing equipment compared to FIG. 1B;
(5) FIG. 1D shows schematically represented a full embodiment of the separation apparatus as partially presented in FIG. 1A with third alternative additional processing equipment compared to FIGS. 1B and 1C;
(6) FIG. 2A shows an schematically represented second embodiment of the separation apparatus including additional subsequent processing equipment according the present invention;
(7) FIG. 2B shows the embodiment of the separation apparatus as presented in FIG. 2A with alternative additional subsequent processing equipment;
(8) FIG. 3 shows an schematically represented third embodiment of the separation apparatus with a first type of additional subsequent processing equipment according the present invention;
(9) FIG. 4A shows an schematically represented fourth embodiment of the separation apparatus with additional subsequent processing equipment according the present invention;
(10) FIG. 4B shows an schematically represented top view of the separation apparatus as presented in FIG. 3A, excluding the subsequent processing equipment;
(11) FIG. 5 shows an schematically represented fifth embodiment of the separation apparatus with additional subsequent processing equipment according the present invention;
(12) FIG. 6 shows a schematically represented sixth embodiment of the separation apparatus with additional subsequent processing equipment according the present invention; and
(13) FIG. 7 shows an schematically represented seventh embodiment of the separation apparatus according the present invention.
DESCRIPTION OF THE INVENTION
(14) FIG. 1A shows a part of a separation apparatus 1 with a spherical vessel 2 having an inlet 3 for feeding a wellstream mixture (e.g. a gas/liquid mixture) according arrow P.sub.1 to the spherical vessel 2. In the spherical vessel 2 a vane diffuser 4 connect to the inlet 3 for enabling (partially) the separation of the inflowing wellstream mixture. At the lower side of the spherical vessel 2 a heavy phase outlet 5 (e.g. a liquid outlet) for the pre-separated substantial heavy fraction (P.sub.2) is located while at the upper side of the spherical vessel 2 a gas outlet 6 for the pre-separated substantial light phase fraction (P.sub.3) (e.g. a gas fraction) is located.
(15) FIG. 1B shows separation apparatus 1 as already partially shown in FIG. 1A, now with a subsequent separator 7 of the compact type that connects to the light phase outlet 6. The subsequent separator 7 in its turn is provided with two liquid fraction outlets 8, 9 and a gas outlet 10. The separation apparatus 1 is also provided with a subsequent separator 11 of the compact type that connects to the heavy phase outlet 5. And also the subsequent separator 11 is again provided with two liquid fraction outlets 12, 13 and a gas outlet 14. FIG. 1C a separation apparatus 15 mainly in line the separation apparatus 1 as shown in FIG. 1B but now with an alternative subsequent separator 16 for the substantial heavy phase fraction leaving the spherical vessel 2 at the lower side of the via heavy phase outlet 5 (P.sub.2). The subsequent separator 16 contains a vessel 17 with a lower heavy phase fraction outlet 18 and a higher light phase fraction outlet 19.
(16) Now in FIG. 1D a separation apparatus 20 is again mainly in line the separation apparatus 1 as shown in FIG. 1B but in this embodiment an alternative subsequent separator 21 for the light phase fraction leaving the spherical vessel 2 at the higher side of the via light phase fraction outlet 6 (P.sub.3). The subsequent separator 21 contains a vessel 22 with a lower heavy phase fraction outlet 23 and a higher light phase fraction outlet 24.
(17) FIG. 2A shows a separation apparatus 30 that has in line with the embodiments shown in FIGS. 1A-1D, a spherical vessel 2 having an inlet 3 for feeding a wellstream mixture according arrow P.sub.1 to the spherical vessel 31. Again in this embodiment in the spherical vessel 2 a vane diffuser 4 connects to the inlet 3 for enabling (partially) the separation of the inflowing wellstream mixture. Also at the lower side of the spherical vessel 2 a heavy phase fraction outlet 5 for the pre-separated substantial heavy phase fraction (P.sub.2) is located while at the upper side of the spherical vessel 2 a light phase fraction outlet 6 for the pre-separated substantial light phase fraction (P.sub.3) is located. Different from the previous embodiments however the spherical vessel 31 of the separation apparatus 30 is provided with a third outlet 32 for a third fraction (P.sub.4), e.g. a substantial oil fraction. By adding the additional third outlet 32 for the removal of a the third fraction the fraction leaving the fraction (P.sub.2) removed through the heavy phase fraction outlet 5 at the lower side of the spherical vessel 2 will now have a different composition (e.g. a larger component of water) as for the pre-separated substantial heavy phase fraction leaving the lower outlet 5 in the embodiments as shown in the FIGS. 1A-1D due to the fact that now also an additional fraction (P.sub.4) is removed via outlet 32 (e.g. a fraction containing an enhanced oil component). The additional fraction (P.sub.4) leaving the third outlet 32 is supplied to a further separation vessel 33 having again a light phase outlet 34 (e.g. a substantial gas outlet) and a heavy phase outlet 35 (e.g. a substantial water outlet). As can be seen from FIG. 2B it is also possible to vary the subsequent processing equipment connecting to the vessel 31. As shown in this embodiment now a vessel 37 having a heavy phase outlet 38 (here e.g. an oil outlet) and a light phase outlet 39 (here e.g. a gas outlet) is connecting to the heavy phase fraction outlet 5 (here e.g. a water outlet) feeding a substantial heavy phase fraction (P.sub.2) (e.g. water) from the vessel 31 while the additional fraction (P.sub.4) (e.g. containing an enhanced oil component) is removed via outlet 32 and is forwarded to a subsequent separator 40 of the compact type that in its turn is provided with two further heavy fraction (e.g. oil) outlets 41, 42 and a light phase fraction (e.g. gas) outlet 43.
(18) Now in FIG. 3 a separation apparatus 50 is shown with a vessel 51 that is a combination of two stacked spherical vessel parts 51 and 51. An inlet 3 for feeding a wellstream mixture according arrow P.sub.1 to the vessel 51 connects to the upper vessel part 51 and leads to vane diffuser 4 for enabling the pre-separation of the inflowing wellstream mixture. At the lower vessel part 51 the heavy phase (e.g. water) outlet 5 for the pre-separated substantial heavy phase fraction (P.sub.2) (e.g. water) and the additional outlet 32 (P.sub.4) (e.g. oil outlet) is located while at the upper vessel part 51 the light phase outlet 6 (e.g. gas outlet) for the pre-separated substantial light phase fraction (P.sub.3) (e.g. substantial gas phase fraction) is located. To further improve the further (e.g. oil/water) separation in the lower vessel part 51 weirs 52 are placed in the lower vessel part 51. For the subsequent processing of the fractions (P.sub.2, P.sub.3, P.sub.4) leaving the vessel 51 subsequent separators 53, 54 and 55 are provided. The subsequent separators 53, 54, 55 may be varied as has been shown in the previous embodiments.
(19) A next embodiment of a separation apparatus 60 is schematically shown in FIGS. 4A and 4B. Here a vessel 61 is an assembly of four spherical vessel parts 61, 61, 61, 61. The heavy phase fraction outlets (e.g. oil fraction outlet 32 and water fraction outlet 5) are located below the liquid level of the fluid mixture that may accumulate on the underside of the vessel 61, in this situation the both the heavy phase fraction outlet 5 (e.g. water outlet) and the additional fraction outlet 32 (e.g. oil outlet) connect to lower vessel part 61. The light phase fraction outlet 6 (e.g. gas outlet) is located on the topside of the vessel 61, so connects to upper vessel part 61. Also here the subsequent separators 63, 64, 65 may be varied as has been shown in the previously. In FIG. 4B only the vessel 61 is shown in a top view further illustrating the vessel 61 being an assembly of four spherical vessel parts 61, 61, 61, 61.
(20) FIG. 5 shows an embodiment of a separation apparatus 70 according the present invention that is more or less in line with the embodiment as shown in FIG. 1A however in this embodiment spherical vessel 71 with inlet 3 for feeding the wellstream mixture according arrow P.sub.1 is now provided with a light phase outlet 72 (e.g. a gas outlet) that is provided with an integrated separator 73 for the subsequent separation of the substantial light phase fraction (P.sub.3) (e.g. a gas phase fraction) that has been pre-separated in the vessel 71. Now the separator 73 integrated in light phase fraction outlet 72 (e.g. a substantial gas phase fraction outlet) can directly dispose the subsequent separated heavy phase fraction (e.g. a substantially liquid phase fraction) in the vessel 71, the dual separated light phase fraction (e.g. gas phase fraction) is further removed according arrow P.sub.5. The heavy phase outlet 5 for the pre-separated substantial heavy phase fraction (P.sub.2) (e.g. substantially liquid phase fraction) connects to a subsequent vessel separator 74 but could also be integrated with the vessel as an alternative embodiment that is also part of the present invention.
(21) Yet a next embodiment of a separation apparatus 80 according the present invention is shown in FIG. 6. Here a spherical vessel 81 is provided with dual light phase fraction outlets 82, 83 (e.g. gas phase outlets) both provided with an integrated separator 84, 85 for the subsequent separation of the light phase fraction (P.sub.3) (e.g. substantial gas phase fraction) that has been pre-separated in the vessel 81. The dual separated light phase fractions are combined and further removed according arrows P.sub.5. In line with the embodiment shown in FIG. 5 also here the heavy phase fraction outlet 5 for the pre-separated heavy phase fraction (P.sub.2) (e.g. substantial liquid phase fraction) connects to a subsequent vessel separator 86.
(22) Finally the embodiment of a separation apparatus 90 that is partially shown in FIG. 7 is in line the embodiment shown in FIG. 5. As done before identical equipment parts are referred to with reference signs as used in earlier embodiments. The difference here compared to the embodiment according FIG. 5 is that before the wellstream mixture is fed to the spherical vessel 71 the mixture is fed according arrow P.sub.6 to a pre-separator 91 from where a pre-separated light phase fraction is directly fed to the separator 73 integrated in light phase outlet 72 according arrow P.sub.7. The remaining pre-separated mixture leaving the pre-separator 91 is fed according arrow P.sub.8 to the inlet 3 of the vessel 71.
