RU2356596C1 - Installation for destruction of water-oil emulsion at transporting it through pipe line - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention refers to preparing oil, particularly to destruction of water-oil emulsions and can be implemented at oil producing and oil refining industries. The installation consists of a pipeline, of one central and several additional partitions in form of rectangular plates arranged parallel and gradually close-coiled, notably, at outlet their edges are turned at 180° relative to edges at input. All partitions at emulsion outlet are equipped with final horizontal sections of lengths growing from top downright. Alternate holes of d=(0.008…0.010) m diametre are bored on horizontal sections of the partitions. Distance between the holes is (3…8)·d. Nearest end of holes along fluid flow direction is bent downward, while the distant one is bent upward; also the angle of bent is 30°…45°.

EFFECT: reduced time required for preliminary oil dehydration which results in reduction of metal consumption for preparing 1 t of oil.

2 cl, 6 dwg, 1 tbl

Description

The proposal relates to the preparation of oil, in particular to the destruction of oil-water emulsions, and can be used in the oil and oil refining industries.

A device is known for destroying a water-oil emulsion during transportation through a pipeline, including a pipeline and a longitudinal horizontal partition installed in the central part of its cross section, which is made in the form of a rectangular plate smoothly rolled in a spiral, while its outlet edge is rotated 180 ° with respect to to the edge at the inlet of the emulsion (see AS 1142499, C10G 33/06, B01D 17/04, publ. BI No. 8 of 02.28.1985).

The disadvantage of this device is the insufficient efficiency of the destruction of the oil-water emulsion: the released free water and large drops, which appeared after the septum in the upper part of the pipe, are directed downwardly dispersed in the flow of oil through the edge of the septum in its rear part. As a result, the part of the water-oil emulsion stream, which turned out to be lower than the partition after it, in which small drops predominate, passes through water dispersed in oil in a small area, and therefore, the interaction of small drops and free water is either insignificant or absent altogether, which does not allow as much as possible to produce the destruction of the emulsion.

The closest in technical essence to the proposed one is a device for the destruction of oil-water emulsions during transportation through a pipeline, including a pipeline, a central and additional, installed in parallel and symmetrically relative to the central, partitions made in the form of rectangular plates, smoothly rolled in a spiral, and their edges at the exit rotated 180 ° with respect to the edges at the entrance, while all the partitions are equipped at the output of the emulsion with finite horizontal sections with a length of less than 1.8 times the diameter of the pipe, increasing from top to bottom, and the final horizontal section of each partition below is made at least 0.5 m longer than the same section of the overlying partition (see the positive decision of 06/18/2007 by application No. 2006113456 / 15 (014622) dated 04/20/2006).

The disadvantage of the device is the need for strict horizontal horizontality of the edges of the partitions at the outlet, which is technically difficult to perform when installing the structure in the field, and if this condition is not met, the efficiency of the device is reduced, since there are zones in the stream under the edges of the partitions at the outlet, above which there is no free water layer it is substantially less in thickness than that which corresponds to the case of strict horizontal partitioning, which leads to uneven processing cing volumes water emulsion due to the passage through the layer of water flowing down from the walls of different thicknesses.

An object of the invention is to improve the quality of the destruction of the oil-water emulsion in the oil recovery system, reducing the time required for preliminary dehydration of the oil, which will lead to a reduction in metal costs for the preparation of 1 ton of oil by reducing the required amount of settling equipment and reducing the amount of additional dosing of the demulsifier supplied to oil preparation unit.

The technical problem is solved by the proposed device for the destruction of the oil-water emulsion during transportation through the pipeline, including the pipeline, the central and additional, installed in parallel and symmetrically relative to the central, partitions made in the form of rectangular plates, smoothly rolled in a spiral, and their edges at the exit are rotated 180 ° with respect to the edges at the entrance, while all the partitions are equipped at the output of the emulsion with finite horizontal sections with a length of at least 1.8 pipe diameters, velichivayuscheysya downward, and the end portion of each horizontal partition situated below, is formed longer by not less than 0.5 m a similar section overlying baffle.

What is new is that in horizontal sections of the partitions holes were drilled with a diameter of d = (0.008 ... 0.010) m in a checkerboard pattern, and the distance between the holes is (3 ... 8) · d, while the edge of the holes nearest the direction of the liquid flow is bent downward, and far - up, and the bending angle is 30 ° ... 45 °.

Figure 1 schematically shows the proposed device, a longitudinal section; figure 2 - horizontal sections of the partitions of the proposed device; figure 3 is a section aa in figure 1; figure 4 is a section bB in figure 1; figure 5 is a section bb in figure 1; figure 6 is a view of G.

The proposed device includes a pipeline 1 (see figure 1), a horizontal central partition 2 and additional partitions 2 ', parallel and symmetrically mounted relative to the central partition 2, which facilitate the circulation of the layers of the fluid flow. Structurally, each of the partitions - the central 2 and the additional 2 '- is a rectangular sheet of metal attached tightly to the walls of the pipeline and folded smoothly in a spiral so that the left edge of the beginning of the sheet at the end becomes right and vice versa, with the final horizontal section of each partition longer the lower it is located. In Fig. 3, the central partition 2 and additional partitions 2 'are represented by a horizontal profile, and as they move away along the flow, their angle of inclination to the horizon increases and becomes equal to 90 ° (see Fig. 3) and 180 ° (see Fig. 4 ) In horizontal sections of the partitions, holes with a diameter of d = (0.008 ... 0.010) m were stitched in a checkerboard pattern, the distance between the holes being (3 ... 8) · d, while the edge of the holes closest to the direction of the liquid flow was bent downward and the distant upward, and the bending angle is 30 ° ... 45 °.

Such a profile of the partitions 2 and 2 '(see figure 1) allows you to translate the lowest layer of the fluid flow IV (see figure 3) in the uppermost (see figure 5) and vice versa (see figure 3-5) and the rest of the layers I-II-III, into which the input fluid stream is separated, falling on the partitions 2 and 2 '(see Fig. 1), is mirrored relative to the central partition 2. In this case, the released free water from the lowest layer of the IV stream passes to the uppermost, and the uppermost layer I, in which the number of small drops substantially prevails over the number of large ones, goes to the uppermost lower layer of fluid flow. The remaining layers, into which the input emulsion stream falling onto the partitions are divided, mirror their position in the emulsion stream relative to the central partition 2. Part of the flow of oil-water emulsion - mostly free water - which appeared after a set of partitions 2 and 2 'in the uppermost zone of the pipeline, flowing through holes in the horizontal part of the partition by a stream and crushing into large drops, allows drops of free water to create favorable conditions for coalescence with them smaller drops of water from the lower flowing layer of the oil-water emulsion, which will lead to a decrease in the concentration of small drops in this layer and the settling of coalesced large drops on the lower-placed partition y. The presence in the proposed device of several partitions 2 and 2 'allows both to reduce the time of gravitational sedimentation of small drops of water that have not passed into the water environment by 2-3 times due to a decrease in the height of their location from the lower generatrix of pipeline 1, and to transfer the remaining drops to the water environment by creating favorable conditions for their coalescence with large drops of free water in all layers of the flow of oil-water emulsion.

According to the results of field studies, depending on the viscosity, density, and speed of the oil-water emulsion moved through the pipeline, the greatest effect can be achieved if the following conditions are met:

- the minimum length of the horizontal section 3 and 3 'of the partitions 2 and 2' is not less than 1.8 pipe diameters;

- each lower horizontal section 3 and 3 'of the partition 2 or 2' should be at least 0.5 m longer than the overlying one;

- the diameter of the holes that are staggered in the horizontal part of the partitions should be equal to d = (0.008 ... 0.010) m;

- the distance between the holes should be (3 ... 8) · d;

- the edge of the holes closest in the direction of the fluid flow should be bent downward, and the distant should be upward, and the bending angle should be 30 ° ... 45 °.

Thus, the holes drilled in the horizontal partitions 2 and 2 'contribute to the acceleration of the destruction of the oil-water emulsion by creating more favorable conditions for the coalescence of large drops of free water, into which the jets of water flowing from the upper partitions, with smaller drops of water present in layers of oil-water emulsion moving under the partitions, which in the future will improve the quality of destruction of the oil-water emulsion in the oil gathering system, and therefore, reduce the time Names necessary for preliminary dehydration of oil, and will lead to a reduction in metal costs (the necessary amount of settling equipment) for the preparation of 1 ton of oil and the consumption of demulsifier reagent.

An example of a specific implementation.

Oil-water emulsion, characterized by the following parameters:

- fluid performance up to 9600 m ³ / day - water cut up to 92% - viscosity 78-200 MPa · s - density 920-960 kg / m ³ - iron sulfide content - 75-1600 mg / dm ³ ,

transported via pipeline 1 with a diameter of 500 mm with a device for breaking the oil-water emulsion, which consists of three horizontal partitions - central 2 and two additional 2 '. The final horizontal section 3 'of the uppermost partition 2' had a length of 1.2 m, and those located below 2.0 m and 2.7 m, respectively. The diameter of the holes drilled in the horizontal sections of the partitions 3 and 3 'was equal to 0.008 m, the distance between the holes was 0.045 m.The closest edge of the holes in the direction of liquid flow was bent downward, and the distant upward, and the bending angle was 45 °. The speed of the oil-water emulsion was 0.3 ... 0.6 m / s. The results of the studies are shown in the table.

№№ Sounding place Volume fraction of water,% Phase separation in the oil pipeline (water level), m upper flow section average flow section lower flow section one To device 12.0 44.0 84.0 0.140 2 After the device (2 m after its end) 8.0 28.0 100.0 (water) 0.185

As can be seen from the data given in the table, after the proposed device, the volume fraction of water in oil in the upper layer of the stream was 8.0%, closer to the middle of the stream 28.0%. According to the prototype, the volume fraction of water in oil in the upper section of the flow was 12 ... 24%.

The technical and economic efficiency of the proposed device consists of reducing the time required for preliminary oil dehydration, which leads to a reduction in metal costs for the preparation of 1 ton of oil by reducing the required amount of settling equipment and to reduce the amount of additional dosing of the demulsifier supplied to the oil treatment unit. As a result of using the device, metal costs are reduced - 1 ... 2 settling apparatus with a capacity of 200 m ³ each are released on the preliminary separation unit of free formation water, and a demulsifier reagent is also saved in the calculation of (5 ... 10) · 10 ^-6 kg / kg of oil.

Claims (2)

1. A device for the destruction of water-oil emulsions during transportation through the pipeline, including the pipeline, the central and additional, installed in parallel and symmetrically with respect to the central partition, made in the form of rectangular plates, smoothly rolled in a spiral, and their edges at the exit are rotated 180 ° relative to edges at the entrance, while all the partitions are equipped at the output of the emulsion with finite horizontal sections with a length of at least 1.8 pipe diameters increasing from top to bottom, and the final the isontal section of each partition below is made at least 0.5 m longer than the same section of the overlying partition, characterized in that stitches are drilled in horizontal sections of the partitions with a diameter of d = (0.008 ... 0.010) m, the distance between the holes is (3 ... 8) · d. 2. The device according to claim 1, characterized in that the edge of the holes closest to the direction of the fluid flow is bent downward and the distal upward, and the bending angle is 30-45 °.

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