WO1997047853A1

WO1997047853A1 - Method and device for rinsing and/or cleaning delivery piping

Info

Publication number: WO1997047853A1
Application number: PCT/AT1997/000119
Authority: WO
Inventors: Karl Heinz Krehan
Original assignee: Sbs Drilling- And Production-Systems Gmbh & Co. Kg
Priority date: 1996-06-12
Filing date: 1997-06-10
Publication date: 1997-12-18

Abstract

A method and device for rinsing and/or cleaning delivery piping (2), in particular an essentially vertical crude-oil production pipeline, with the delivery pipe (2) being located in a casing (1) that surrounds the delivery pipe (2), forming an annulus, and with the fluid to be delivered being discharged, in particular pumped, via the delivery pipe (2). For rinsing and/or cleaning, the delivery of the fluid to be delivered in the delivery pipe (2) is interrupted, a rinsing fluid is introduced, in particular injected under pressure, into the casing (1) that surrounds the delivery pipe (2), forming an annulus, and the rinsing liquid is introduced into the interior of the delivery pipe (2) via one or more sealable openings in the jacket of the delivery pipe (2) that open into its interior, and preferably discharged through the delivery pipe (2).

Description

METHOD AND DEVICE FOR FLUSHING AND / OR CLEANING A CONVEYOR LINE

The present invention relates to a method for flushing and / or cleaning a delivery line, in particular an essentially vertically running oil delivery line, the fluid to be delivered being discharged, in particular pumped, via the delivery line. The invention further relates to a device for rinsing and / or cleaning a delivery line, in particular an essentially vertically running oil delivery line, the delivery line being arranged in a casing pipe surrounding the delivery line with the formation of an annular space.

In the case of delivery lines, in particular petroleum delivery lines, it is known that with time deposits of constituents and contaminants of the fluid to be delivered can separate out on the inner walls of the delivery line, which over time leads to a considerable narrowing of the clear delivery cross section of the delivery line with a resultant reduction in the delivery capacity or excessive stress on a pump device or complete blockage of the delivery line. Such a move of the conveying line can be carried out in the production of crude oil in particular by itself niederschla¬ constricting or solidifying paraffins, wherein the fine Paraf¬ in dependence of their specific composition, as well as optionally further present Verunreini¬ conditions a solidification temperature of about 30 C to ^β 80 ° C, even if the oil extracted from the interior of the earth is at a higher temperature, a corresponding cooling takes place during transport to the earth's surface, depending on the ambient conditions, so that relatively precisely definable zones or areas are formed in the interior of the production line which the cross-section of the delivery line is relocated by depositing or solidifying the paraffins. In order to counteract such a laying of the delivery line, it is known, for example as a preventive treatment, to introduce chemical additives into the fluid to be delivered in order to solidify components of the fluid to be delivered which melt at higher temperatures, for example paraffins, and to avoid contamination in any case. A disadvantage of this procedure, however, is the fact that the chemical additives used are mostly extremely costly and can be used in relatively large amounts, and furthermore that the added materials are subsequently removed, which is sometimes very complex, in the subsequent treatment or refining of the crude oil produced got to. In addition, undesired chemical or thermal reactions with elastomeric parts can occur.

For cleaning conveyor lines, it is also known to use mechanical additional devices and to introduce them into the conveyor line, which, however, usually results in interruptions in the conveying activity and such methods, in particular due to the long time required for retrofitting and the use of mechanical cleaning devices overall are therefore also very expensive.

On the basis of the known method mentioned at the outset, the present invention now aims to provide a simple and easy to carry out method for rinsing and / or cleaning a delivery line, by means of which contaminants, in particular separated deposits, are deposited in the interior of the delivery line Paraf¬ fine can be removed in a targeted manner, quickly and inexpensively in an oil production line. In particular, the aim is to ensure that a short interruption in the promotional activity is sufficient and, in particular, that a conversion to use mechanical cleaning devices can be dispensed with. To achieve these tasks, the method according to the invention is essentially characterized in that, based on the method of the type mentioned at the outset, the pumping of the fluid to be conveyed in the delivery line is interrupted for rinsing and / or cleaning, that a flushing liquid flows into the delivery line to form a Annular space surrounding casing is introduced, in particular pressed in, and that the rinsing liquid is introduced into the interior of the conveying line via at least one closable opening that opens into the interior of the conveying line and is preferably discharged through the conveying line. The fact that, according to the invention, a flushing liquid is introduced into the interior of the delivery line via the annular space defined by the feed pipe, in particular pressed in, can be used to convey the fluid to be obtained, in particular crude oil without chemical additives, and with short interruptions in the conveying activity, a safe removal of deposited contaminants or fluid components can be carried out. Conversely, there is no need for any retrofitting work to clean or rinse the delivery line and thus cleaning and rinsing in a very short time and with the targeted introduction of the rinsing liquid from the annular space defined by the feed pipe surrounding the delivery line at a defined position in the interior of the Delivery line can be made. Furthermore, since the rinsing takes place after the delivery has been interrupted, there is no impairment of the contents of the fluid to be delivered which would require additional treatment to separate the introduced rinsing liquid. Furthermore, a directed flushing from the annular space into the delivery line can be maintained or, if desired, a multiple reversal of the direction of flow of the flushing liquid between the inside of the delivery line and the annular space through the opening in the jacket of the delivery line to improve the flushing and cleaning effect made in order in this way to cause the deposits to be removed as quickly and completely as possible.

In order to achieve a reliable detachment and removal of the impurities on the inner wall of the delivery line, the method according to the invention is preferably further developed such that the delivery line is rinsed with a rinsing liquid with a higher temperature than the fluid to be delivered, in particular with hot water or hot oil is rinsed. Such a rinsing liquid can be used simply and inexpensively and is readily available and usable in large quantities due to the fact that the rinsing liquid does not have to meet any purity requirements. In a particularly preferred manner, the procedure is such that the delivery line is rinsed with hot water at a temperature close to its boiling point. Deposited substances, such as paraffins, can be safely removed in this way, which solidify at the temperatures indicated above and in turn liquefy with hot water near the boiling point and are carried away. Furthermore, the paraffins can be easily separated from the rinsing liquid formed by hot water and can thus be used or reused if necessary.

For a targeted introduction of the rinsing liquid into the interior of the delivery line, it is preferably proposed that the rinsing liquid is deflected into the interior of the delivery line in the region of the at least one opening on the jacket of the delivery line. Such a deflection can take place, for example, by providing corresponding deflection devices in the area of the at least one opening opening into the interior of the conveying line, such additional mechanical devices, which can be adjusted in a favorable manner, being prone to malfunction in the rough conveying operation and being easily damaged under certain circumstances. According to a preferred embodiment of the method according to the invention, the procedure here is such that the deflection of the rinsing liquid by adjusting the level of the fluid to be conveyed in the through the casing defined annular space is carried out to a level just below the position of the at least one opening of the delivery line. The level of the fluid to be conveyed can easily be adjusted by appropriate pumping immediately before the interruption of the conveying activity, the fluid remaining in the annular space formed by the casing allowing an effective deflection of the flushing liquid introduced into the annular space from above into the interior of the conveying line . When using hot water or an oleophobic rinsing liquid in general, the level of the fluid to be conveyed also forms a well-defined temporary boundary zone and thus a safe deflection, so that mixing of the rinsing liquid with the fluid is largely avoided, but only small amounts of the producing crude oil are carried away with the rinsing liquid. In the interior of the delivery line, the pump usually provided at the end arranged in the interior of the earth provides a tight closure of the delivery line so that the flushing liquid introduced into the interior of the delivery tube via the annular space of the casing tube with reliable removal and entrainment of the deposits, for example Paraffins, is brought up from the delivery line.

In order to ensure reliable and rapid removal or detachment of the impurities, even in the case of delivery lines with a large cross-section over the entire clear cross-section of the delivery line, it is also preferred that the rinsing liquid on the jacket of the delivery line over a plurality of closable openings in a common plane is introduced normally to the longitudinal direction of the delivery line. The rinsing liquid is thus introduced evenly through a plurality of openings arranged on the circumference of the delivery line.

For a simple removal of large-scale deposits which have accumulated over a large longitudinal extent of the delivery line, it is further preferred that the rinsing liquid be on the jacket of the delivery line is introduced via a plurality of closable openings in different planes along the longitudinal direction of the delivery line. It is thus possible to carry out rapid and reliable cleaning of large lengths of pipe by simply supplying rinsing liquid at different levels to the interior of the conveying line, advantageously in succession.

The present invention further relates to a device for rinsing and / or cleaning a delivery line, in particular an essentially vertically running oil delivery line, the delivery line being arranged in a casing which surrounds the delivery line to form an annular space and which is used to solve the above - The above-mentioned objectives are essentially characterized in that at least one closable opening opening into the inside of the delivery line for introducing a rinsing liquid from the annular space formed by the feed pipe into the interior of the delivery line is provided on the jacket of the delivery line. By providing such a closable opening, a simple and inexpensive construction can be achieved which has no adverse effect on the conveying activity and specifically allows a flushing liquid to be introduced into the interior of the conveying line at at least one precisely defined position. The positioning of the opening can be exactly defined, for example, by determining a temperature profile over the entire delivery head and taking into account the properties of the deposits to be expected, in order to introduce the rinsing liquid essentially just below the area containing the deposits into the interior of the conveyor ¬ ensure conduction.

According to a particularly preferred embodiment, it is provided according to the invention that the closable opening is provided at a distance of at least 20 m from a pump arranged at the end of the delivery line arranged in the interior of the earth. By this distance of the opening from the pump it is ensured that, in particular, plastic parts of the pump are not damaged by the flushing liquid, which may be aggressive or corrosive to plastics, thereby increasing the service life of the pump, the replacement of which is usually associated with time-consuming dismantling of the boom over great depths can be. Maintaining such a distance is easily possible in the case of conveyor lines with long lengths of up to a few thousand meters, since the deposits are usually at a depth of a few hundred meters.

In order to avoid a hindrance to the conveying activity by providing the closable opening in the jacket of the conveyor line, it is preferably proposed that a closure device for the opening on the jacket of the conveyor line has a closure member lying within the thickness of the jacket of the conveyor line. This ensures that the entire clear cross-section of the delivery line is available for the delivery of the fluid.

For a particularly reliable and easy-to-operate closure of the at least one opening, it is proposed according to a further preferred embodiment that the opening on the jacket of the delivery line can be closed by a valve which opens at least in the direction of the interior of the delivery line. Such a valve can be matched in a simple manner to the conditions of the supply of the flushing liquid by appropriate selection of the valve characteristics. If desired, a valve which can be actuated or opened in both directions can also be provided, so that, for a further improvement in the cleaning or rinsing effect, the flow direction of the rinsing liquid between the inside of the delivery line and the annular space formed by the casing can be reversed if necessary. In order to form a valve construction which is as flat as possible and which can be accommodated in the region of the thickness of the jacket of the delivery line, it is provided according to a further preferred embodiment that the valve consists of a carrier which can be fixed in the jacket of the delivery line and has at least one passage opening in which a valve body displaceable against the force of a spring can be moved in a direction normal to the jacket of the delivery line, and that the valve body is self-centering with a plate-shaped valve member at its valve seat in the carrier. By selecting the spring force and the valve surfaces, the pressure conditions of the flushing liquid can be matched with a simple and robust construction of the valve.

In order to achieve a sufficient sealability without additional sealing elements with the valve being as flat as possible, it is preferably proposed in this connection that the plate-shaped valve member is formed with a sealing surface forming part of a spherical surface, which results in simple workability the valve surface can automatically achieve a self-centering of the valve body relative to the seat surface.

For a particularly simple arrangement of the at least one opening for supplying rinsing liquid into the interior of the delivery line along the longitudinal extent thereof at a desired position without complex machining of the tube forming the delivery line, the design according to the invention is preferably such that the at least one, in particular by each a valve which can be closed and which opens into the interior of the delivery line is formed with the closure device in an intermediate piece which can be fixed, in particular screwed, in the extension of the delivery line. Such an intermediate piece can be formed in a simple manner with corresponding connection elements, such as sleeves, screw connections or the like, for a connection to the other tubular elements, so that it is easier Way, the intermediate piece can be integrated into the desired location of the delivery line.

For appropriate protection of the delivery line in the area of the at least one opening opening into the interior, it is also preferably provided that the delivery line in the area of the at least one opening is provided on its outer circumference with a protective or covering element and / or a centering element .

In order to further promote a uniform introduction of the rinsing liquid over the entire circumference of the delivery line in order to simplify the removal of deposits, it is proposed according to a further preferred embodiment that a plurality of closable openings in a common plane are normal on the surface of the delivery line are provided on the longitudinal direction of the delivery line.

For simple cleaning of large pipe lengths, it is also preferably provided that a plurality of closable openings are provided on the jacket of the delivery line in different planes along the longitudinal direction of the delivery line.

The invention is explained in more detail below with the aid of exemplary embodiments shown schematically in the accompanying drawing. In this show:

1 shows a schematic representation of a device according to the invention for carrying out the method according to the invention for rinsing and / or cleaning a delivery line;

2 on an enlarged scale, a section II in FIG. 1 marked by a dashed circular line through an intermediate piece of a device according to the invention, on which a plurality of openings opening into the interior of the delivery line are provided;

3 shows a section along the line III-III of FIG. 2 through a valve element of the device according to the invention, FIG. 2 showing a section along the line II-II of FIG. 3; and FIG. 4 shows, in a representation similar to FIG. 2, a section through a modified embodiment of an intermediate piece of a device according to the invention.

1 generally shows a section through an oil production bore, a production line 2 being arranged in a casing 1 or casing, on the end of which facing the interior of the earth, for example, the stator 3 of a screw pump is arranged. Fluid to be conveyed penetrates into the interior of the casing 1 via a perforation zone 4 provided with openings and is discharged from the casing 1 through the delivery line 2 via the pump 3, as indicated by the arrow 5.

At a distance of at least 20 m above the stator 3 of the pump, at least one opening opening into the interior of the delivery line 2 is provided on the delivery line 2 in area II, as will be shown in more detail in FIGS. 2 and 4 via the opening arranged in area II of FIG. 1 can be flushed into the interior of the conveyor line 2, for example hot water near its boiling point, for flushing and cleaning into the interior of the conveyor line 2, for example to remove deposited or deposited paraffins , be introduced. The rinsing liquid is introduced or pressed in in the annular space 6 defined by the feed pipe 1 in accordance with the arrow 7 and deflected directly in the area II for introduction into the interior of the delivery line 2. The deflection of the rinsing liquid in the region of the opening opening into the interior of the delivery line 2 can take place, for example, by setting the mirror 8 of the fluid to be delivered just below the position of the opening in the delivery line 2 before the delivery activity is interrupted, so that the Level 8 of this fluid directly causes the rinsing of the rinsing liquid.

For cleaning long pipe lengths, openings at different heights can be provided along the delivery line 2. be seen, an appropriate adjustment of the mirror 8 in the annular space 6 being carried out for a corresponding deflection.

2 and 3, part II of FIG. 1 is shown on an enlarged scale, wherein it can be seen that in an intermediate piece 9, which can be connected via screw connections 10 and 11 to subsequent pipe elements of the conveying line 2, and thus a part of the conveying line - device 2 forms, over the circumference a plurality of openings 13 opening into the interior 12 of the delivery line are formed. A valve 14 is arranged in each of the openings 13 so that it can be closed, a valve body 17, which is displaceably mounted against the force of a spring 16, being arranged in a valve carrier 15 and having a plate-like end at its end facing the interior 12. shaped valve member 18 carries.

In the closed valve positions shown on the underside in FIG. 2, it can be seen that the plate-shaped valve member 18 does not protrude into the interior 12 of the intermediate piece 9 and thus the delivery line 2 and thus does not influence the delivery activity. When a rinsing liquid is introduced into the annular space 6 surrounding the delivery line 2 and the intermediate piece 9, in the embodiment shown in FIG. 2, the passage openings 19 provided in the valve carrier 15 are opened by lifting the plate-shaped valve member 18 from of the valve seat surface 20 formed in the carrier 15, as shown in FIG. 2 above. The rinsing liquid introduced into the interior 12 in this way causes deposits or deposits on the inner wall of the delivery line 2 to be removed when it passes through the delivery line 2.

In order to achieve a sufficient sealing function without additional provision of sealing elements with a very flat construction of the valve 14, it is also provided that the plate-shaped valve member 18 with a part of a is schematically formed with 21 designated spherical surface forming sealing surface and bears with this on the seat surface 20 of the carrier 15.

In the area of the arrangement of the openings 13, the intermediate piece 9 is also formed with a reinforced cross section for forming a protective or covering element 22 and additionally with a centering element 23.

In the modified embodiment shown in FIG. 4, the reference numerals of the preceding figures have been retained for the same components. In turn, a plurality of openings 13 are provided in an intermediate piece 9 distributed over the circumference thereof, in which valves 14 which are open to the interior 12 of the intermediate piece 9 and thus the delivery line 2 are arranged. A protective or cover element in the area of the valves 14 is designated 24.

In the event that not only an introduction of the rinsing liquid from the annular space 6 surrounding the delivery line 2 and the intermediate piece 9 is desired into the interior 12, but also a reversal of the flow direction of the rinsing liquid is to be achievable, of course Correspondingly modified closure or valve constructions are provided which allow passage through the intermediate piece 9 or generally through the delivery line 2 in both directions.

Claims

Patent claims

1. A method for rinsing and / or cleaning a delivery line (2, 9), in particular an essentially vertically running oil delivery line, the fluid to be delivered being discharged, in particular pumped, via the delivery line (2, 9), thereby characterized in that, for flushing and / or cleaning, the conveyance of the fluid to be conveyed in the conveying line (2, 9) is interrupted, that a flushing liquid flows into a casing pipe (2) surrounding the conveying line (2, 9), forming an annular space (6). 1) is introduced, in particular pressed in, and that the rinsing liquid is introduced into the interior of the conveyor line (2, 9) via at least one closable opening (13) opening into the interior (12) of the delivery line (2, 9) and in front of it ¬ is preferably applied by the conveyor line (2, 9).

2. The method according to claim 1, characterized in that the delivery line (2, 9) is rinsed with a rinsing liquid with a higher temperature than the fluid to be conveyed, in particular with hot water or hot oil.

3. The method according to claim 2, characterized in that the delivery line (2, 9) is rinsed with hot water at a temperature near its boiling point.

4. The method according to claim 1, 2 or 3, characterized gekennzeich¬ net that the rinsing liquid in the region of the at least one opening (13) on the jacket of the delivery line (2, 9) into the interior (12) of the delivery line (2, 9) is redirected.

5. The method according to claim h, characterized in that the deflection of the rinsing liquid by adjusting the level of the fluid to be conveyed in the through the casing (1) defined annular space (6) to a level just below the position of the at least one opening (13) Conveying line (2, 9) is made.

6. The method according to any one of claims 1 to 5, characterized ge indicates that the rinsing liquid on the jacket of the Förder¬ line (2, 9) via a plurality of closable openings (13) in a common plane normal to the longitudinal direction of the delivery line (2, 9) is introduced.

7. The method according to any one of claims 1 to 6, characterized ge indicates that the rinsing liquid on the jacket of the Förder¬ line (2, 9) via a plurality of closable openings (13) in different planes along the longitudinal direction of the Delivery line (2, 9) is introduced.

8. Device for rinsing and / or cleaning a delivery line (2, 9), in particular an essentially vertically extending petroleum supply line, the delivery line (2, 9) in a delivery line (2, 9) to form an annular space (6 ) surrounding casing (1), characterized in that on the jacket of the delivery line (2, 9) at least one closable opening (13) opening into the inside of the delivery line (2, 9) for introducing a rinsing liquid from the through the casing (1) formed in the interior (12) of the delivery line (2, 9) is seen vor¬.

9. The device according to claim 8, characterized in that the closable opening (13) is provided at a distance of at least 20 m from a pump (3) arranged at the end of the delivery line (2, 9) arranged in the interior of the earth.

10. The device according to claim 8 or 9, characterized gekennzeich¬ net that a closure device of the opening (13) on the jacket of the delivery line (2, 9) within the thickness of the jacket of the delivery line (2, 9) lying closure member (14 ) having.

11. The device according to claim 8, 9 or 10, characterized gekenn¬ characterized in that the opening (13) on the jacket of the delivery line (2, 9) by an at least towards the inside (12) of the Delivery line (2, 9) opening valve (14) can be closed.

12. The apparatus according to claim 11, characterized in that the valve (14) from a in the jacket of the delivery line

(2, 9) fixable carrier (15) with at least one passage opening (19), in which a valve body (17) displaceable against the force of a spring (16) in a normal manner on the jacket of the delivery line (2, 9) standing direction, and that the valve body (17) with a plate-shaped valve member (18) is self-centering on its valve seat (20) in the carrier (15).

13. The apparatus according to claim 12, characterized in that the plate-shaped valve member (18) is formed with a part of a spherical surface (21) forming the sealing surface.

14. Device according to one of claims 9 to 13, characterized in that the at least one, in particular by a valve (14) lockable, in the interior (12) of the delivery line (2, 9) opening (13) with the Ver ¬ closing device (14) is formed in an intermediate piece (9) which can be fixed, in particular screwed, in the extension of the delivery line (2, 9).

15. The device according to one of claims 9 to 14, characterized in that the conveyor line (2, 9) in the region of the at least one opening (13) on its outer circumference with a protective or cover element (22, 24) and / or a centering ¬ element (23) is provided.

16. Device according to one of claims 9 to 15, characterized in that on the jacket of the delivery line (2, 9) a plurality of closable openings (13) are provided in a common plane normal to the longitudinal direction of the delivery line (2, 9) are.

17. Device according to one of claims 9 to 16, characterized in that a plurality of closable openings (13) are provided in different planes along the longitudinal direction of the conveyor line (2, 9) on the jacket of the conveyor line (2, 9).