Protection assembly and air separation cold box

Abstract

The utility model provides a protection assembly and an air separation cold box. In the protection assembly, a protection cover is detachably connected outside the two pipelines. The annular stop wall of the protective cover surrounds the butt flange for a whole circle, and the axial stop piece comprises two side stop walls which are connected to the two sides of the annular stop wall respectively in the axial direction. The inlet end of the liquid receiving pipe is arranged on the annular stop wall, and the outlet end of the liquid receiving pipe penetrates through the box wall and extends out of the box wall. And the outlet end is lower than the inlet end, so that leaked liquid leaked from the butt flange flows out of the tank wall through the liquid receiving pipe after being stopped by the annular stop wall and the axial stop piece. The plug is detachably arranged at the outlet end, located outside the box wall, of the liquid receiving pipe and plugs the outlet end. The protection assembly can effectively prevent low-temperature leaked liquid from damaging the wall of the cold box.

Description

Technical Field

[0001] The utility model belongs to the field of air separation, relates to an air separation cold box, and in particular to a protection component. Background Art

[0002] The air separation cold box is the core equipment of the air separation plant. All devices and piping systems in the air separation cold box operate at very low temperatures, so a carbon steel box filled with pearlescent sand is usually used for insulation. In order to prevent the leakage of cryogenic liquid and damage to the steel structure of the cold box, pipe connections are usually welded as much as possible. However, in some cases, a pair of flanges are required to connect the pipes. The flange structure often has the problem of internal flow leakage. When a leak occurs in the cold box, the cryogenic liquid or gas in the cold box will cause overpressure in the cold box. In severe cases, the cryogenic liquid splashes onto the steel structure of the cold box, causing the beams and columns of the steel structure to become cold and brittle, destroying the support system of the cold box, and causing the cold box to collapse.

[0003] Chinese utility model patent CN217845522U discloses a device for preventing leakage damage inside a cold box. The device comprises a liquid guide disposed below a leakage risk point and a partition connected to the liquid guide, and at least one end of the liquid guide and the partition is fixed to the inner wall of the cold box panel and forms a leakage prevention space surrounding the leakage risk point.

[0004] In actual use, the above-mentioned device can effectively reduce leakage damage, but there is still a risk of low-temperature leakage damaging the cold box wall. Utility Model Content

[0005] The utility model aims to provide a protection component which can more effectively prevent low-temperature liquid leakage from damaging the wall of a cold box.

[0006] The utility model provides a protection component for an air separation cold box. Two pipes connected by a butt flange are arranged in the box space surrounded by the box wall of the air separation cold box. The butt flange defines the circumferential direction and the axial direction. The protection component includes a protection cover, a liquid receiving pipe and a plug. The protection cover is detachably connected to the outside of the two pipes, and includes an annular stop wall and an axial stop member. The annular stop wall surrounds the butt flange in a full circle, and the axial stop member includes two side stop walls respectively connected to both sides of the annular stop wall in the axial direction. The inlet end of the liquid receiving pipe is opened in the annular stop wall, and the outlet end of the liquid receiving pipe passes through the box wall and extends out from the box wall. The outlet end is lower than the inlet end, whereby the leaked liquid from the butt flange is stopped by the annular stop wall and the axial stop member and then flows to the outside of the box wall through the liquid receiving pipe. The plug is detachably arranged at the outlet end of the liquid receiving pipe located outside the box wall, and the outlet end is blocked.

[0007] In one embodiment, the docking flange further defines a radial direction. The annular stop wall is a cylindrical wall with openings at both ends, and the annular stop wall has a bottom section periphery including a lowest point at each end, and the side stop wall extends radially inwardly from the bottom section periphery.

[0008] In one embodiment, the protrusion height of the side baffle wall is set to allow the annular stop wall with the side baffle wall to move axially over the docking flange. The protrusion height is above 1 cm.

[0009] In one embodiment, the depth of the cylindrical wall is three to four times the axial dimension of the docking flange. The annular stop wall is symmetrically arranged relative to the docking seam of the docking flange in the axial direction. The periphery of the bottom section is the lower half of the overall periphery of the cylindrical wall.

[0010] In one embodiment, the protection assembly further includes a supporting structure. The protection cover is detachably connected to the outside of the two pipes through at least two supporting structures. The supporting structure includes a first connecting wall, a second connecting wall and an intermediate connecting wall. The first connecting wall is fixedly connected to the protection cover, the second connecting wall is fixedly connected to one of the two pipes, and the intermediate connecting wall is detachably connected to the first connecting wall and the second connecting wall.

[0011] In one embodiment, in the support structure, the first connecting wall is welded to one end of the annular stop wall of the protective cover in the axial direction, and has a first connecting portion that protrudes radially outward and exceeds the annular stop wall. The second connecting wall extends radially outward from the outer surface of a pipe and has a second connecting portion at the radial outer end. The intermediate connecting wall has an outer connecting portion and an inner connecting portion that are respectively located on the outer side and the inner side in the radial direction, and the first connecting portion and the second connecting portion are detachably connected to the outer connecting portion and the inner connecting portion respectively by fasteners.

[0012] In one embodiment, the intermediate connecting wall has a straight plate portion extending perpendicularly to the axial direction, the outer connecting portion of the intermediate connecting wall is a part of the straight plate portion, and the fastener connecting the first connecting portion and the outer connecting portion passes through the axial direction. The inner connecting portion of the intermediate connecting wall is bent relative to the straight plate portion and extends along the axial direction, the second connecting portion of the second connecting wall corresponds to the inner connecting portion and extends along the axial direction, and the fastener connecting the second connecting wall and the inner connecting portion passes through the radial direction.

[0013] In one embodiment, the inner connection portion is located on a side opposite to the mating flange relative to the straight plate portion in the axial direction.

[0014] In one embodiment, the protection component further includes an alarm system. The alarm system includes a temperature sensor and an alarm. The temperature sensor is arranged at the inlet end of the liquid receiving pipe. The alarm sends an alarm signal according to the temperature sensing signal of the temperature sensor.

[0015] The utility model also provides an air separation cold box, comprising the aforementioned protection component.

[0016] In the above-mentioned protective assembly, when low-temperature liquid leaks out at any place of the docking flange, the low-temperature liquid leakage will be stopped by the annular stop wall and flow to a lower place under the guidance of the annular stop wall. Cooperating with the axial stop function of the axial stopper, the leaked liquid can be guided to the plug outside the box wall through the liquid receiving pipe connected to the annular stop wall. The low-temperature liquid leakage will not contact the cold box at all. Moreover, since the temperature of the leaked liquid is very low, ice or frost will form at the plug, which can easily remind the operator. Therefore, the above-mentioned protective assembly can effectively prevent the low-temperature liquid leakage from damaging the wall of the cold box.

[0017] Moreover, the protective cover is detachably connected to the outside of the pipe, so that the flange structure can be easily inspected by removing the protective cover. Moreover, the plug can also be removed, so that the leaked liquid can be discharged later. The leaked liquid will not contact the cold box wall at all, so that the low-temperature leaked liquid can be prevented from damaging the cold box wall, thereby preventing a wide range of fault problems.

[0018] Furthermore, in the above-mentioned protective assembly, by adopting a detachable supporting structure, especially by setting the raised height of the side baffle wall, the protective cover can be easily moved out of the maintenance area when there is a leak, and corresponding maintenance operations can be performed on the flange connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The advantages and spirit of the present invention can be further understood through the following detailed description of the invention and the accompanying drawings.

[0020] Figure 1 It is a cross-sectional view of the protective component when viewed along the axial direction.

[0021] Figure 2 is a cross-sectional view of the guard assembly when viewed from the side.

[0022] Figure 3 It is a plan view of the protection component when viewed along the axial direction.

[0023] Figure 4 is a side view of the guard assembly when viewed from the side.

[0024] Figure 5 is along Figure 4 Cross-sectional view taken along line AA. DETAILED DESCRIPTION

[0025] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. However, the present invention should be understood as not being limited to the embodiments described below, and the technical concept of the present invention can be implemented in combination with other known technologies or functions, or other technologies that are the same as those known technologies.

[0026] For example, a first feature described later in the specification as being formed above or on a second feature may include an embodiment in which the first feature and the second feature are formed by direct connection, and may also include an embodiment in which an additional feature is formed between the first feature and the second feature, so that the first feature and the second feature may not be directly connected. Further, when a first element is described as being connected or combined with a second element, the description includes an embodiment in which the first element and the second element are directly connected or combined with each other, and also includes an embodiment in which one or more other intervening elements are added to indirectly connect or combine the first element and the second element.

[0027] For the structure of the cold box with pipes connected by butt flanges, leakage may occur in the flange structure, for example due to pipe stress or vibration of the pipe system caused during operation. In this regard, as mentioned above, devices that can prevent leakage damage can be fixed on the cold box panel. A separation box can also be specially designed. The separation box has an inspection port for easy maintenance. The separation box can be filled with slag wool. In some cases, the bottom of the separation box can have a stainless steel basin to limit the impact of liquid leakage.

[0028] However, both of the above solutions cannot completely prevent the cold box from being damaged by low temperature liquid leakage. When the liquid leakage is serious, it will cause damage to the cold box steel structure, such as the main tower.

[0029] like Figure 1 As shown, the utility model provides a protection assembly 10 for an air separation cold box 100. Correspondingly, the utility model also provides an air separation cold box 100, including the protection assembly 10 mentioned above. Figure 1 and Figure 2 The general structure of the protection assembly 10 is schematically shown. Figures 3 to 5 The more detailed structure of the protection assembly 10 is further shown in detail.

[0030] It is to be understood that the drawings in this document are only for illustrative purposes and are not necessarily drawn in proportion, and should not be considered as limiting the actual scope of protection required by the present utility model.

[0031] Combination Figure 1 and Figure 2 Two pipes 30 connected by a docking flange 20 are arranged in the box space S0 surrounded by the box wall 101 of the air separation cold box 100. For the convenience of description, the circumferential direction C0, axial direction X0 and radial direction R0 are shown in the figure. It can be considered that the docking flange 20 defines the circumferential direction C0, axial direction X0 and radial direction R0. In fact, the circumferential direction C0, axial direction X0 and radial direction R0 can also be relative to any pipe 30, which are respectively the direction around the pipe cross section of the pipe 30, the direction extending along the central axis O1 of the pipe 30, and the direction radiating outward from the central axis O1 of the pipe.

[0032] Continue to see Figure 1 and Figure 2 The protection assembly 10 includes a protection cover 1, a liquid receiving pipe 2 and a plug 3. The protection cover 1 is detachably connected to the outside of the two pipes 30, and includes an annular stop wall 4 and an axial stop member 5. The annular stop wall 4 surrounds the docking flange 20 in a full circle. That is, the annular stop wall 4 is a closed ring around the docking flange 20. The axial stop member 5 includes two side stop walls 51 respectively connected to both sides of the annular stop wall 4 in the axial direction X0.

[0033] The inlet end 21 of the liquid receiving pipe 2 is opened in the annular stop wall 4. The outlet end 22 of the liquid receiving pipe 2 passes through the box wall 101 and extends out of the box wall 101. The outlet end 22 of the liquid receiving pipe 2 is lower than the inlet end 21, whereby the leaked liquid from the docking flange 20 is stopped by the annular stop wall 4 and the axial stopper 5 and then flows to the outside of the box wall 101 through the liquid receiving pipe 2. It can be understood that for the box wall 101, "inside" and "outside" refer to the inside and outside of the box space S0 surrounded by the box wall 101, respectively.

[0034] The plug 3 is detachably disposed at the outlet end 22 of the liquid receiving pipe 2 outside the box wall 101, and blocks the outlet end 22. For example, the plug 3 can be a threaded plug, which is connected to the outlet pipe section of the liquid receiving pipe 2 including the outlet end 22 by threaded connection.

[0035] In the above-mentioned protective assembly 10, if there is leakage at the docking seam 201 of the docking flange 20, no matter where it splashes, it can be blocked by the annular stop wall 4 and flow along the annular stop wall 4 to the lower part of the annular stop wall 4. Due to the stopping effect of the axial stopper 5 on both sides of the axial direction X0, the leakage can be collected in the space surrounded by the annular stop wall 4 and led out by the liquid receiving pipe 2 to the plug 3 outside the box wall 101. The leakage in the air separation cold box is usually a deep-cold liquid, and when it flows to the plug 3, the operator will see a certain range of ice or frost. In this way, you can choose to remove the plug 3 and discharge the leakage to an appropriate location, or perform other maintenance operations. When the flange structure is inspected and repaired, the protective cover 1 can be removed and reinstalled, so the operation is very convenient.

[0036] The protection assembly 10 is directly connected to the pipeline 30 instead of the box wall 101 of the air separation cold box 100, so it can adapt to flange structures at any position, especially flange structures at a higher position.

[0037] See also Figures 3 to 5 The annular stop wall 4 is a cylindrical wall with openings at both ends, in particular, a cylindrical shape. The annular stop wall 4 has a bottom section periphery 41 including a lowest point P4 at each end 40. The side stop wall 51 extends convexly inwardly from the bottom section periphery 41 along the radial direction R0. Figure 3In the embodiment, the raised height h1 of the side baffle wall 51 is set to allow the annular stop wall 4 with the side baffle wall 51 to move over the docking flange 20 in the axial direction X0. That is, when the annular stop wall 4 with the side baffle wall 51 moves in the axial direction X0, the side baffle wall 51 will not interfere with the docking flange 20. The raised height h1 of the side baffle wall 51 is the depth of the side baffle wall 51 extending inward from the bottom section periphery 41 of the barrel end 40 of the annular stop wall 4 in the radial direction R0. The above arrangement can facilitate the movement of the protective component 10 away from the docking flange 20, thereby facilitating the maintenance of the docking flange 20. In addition, the raised height h1 of the side baffle wall 51 is preferably above about 1 cm, so that the effect of axial stop can be ensured. Here, "above" means greater than or equal to, that is, including the endpoint value itself.

[0038] Combination Figure 3 and Figure 4 The protection assembly 10 further includes a supporting structure 6. The protection cover 1 is detachably connected to the outside of the two pipes 30 via at least two supporting structures 6. Figure 4 In the left side (the side of the axial direction X0), the protective cover 1 is provided with two supporting structures 6 ( Figure 3 In the embodiment shown in the figure, the protective cover 1 is supported on the left pipe 30 by two supporting structures 6 (arranged symmetrically with respect to the meridian plane of the left pipe 30), and on the right side, the protective cover 1 is supported on the right pipe 30 by two supporting structures 6 (arranged symmetrically with respect to the meridian plane of the right pipe 30) located at the upper and lower sides of the right pipe 30, respectively. That is, in the illustrated embodiment, a total of four separate supporting structures 6 are provided.

[0039] The supporting structure 6 includes a first connecting wall 61, a second connecting wall 62 and an intermediate connecting wall 63. The first connecting wall 61 is fixedly connected to the protective cover 1, the second connecting wall 62 is fixedly connected to one of the two pipes 30, and the intermediate connecting wall 63 is detachably connected to the first connecting wall 61 and the second connecting wall 62 respectively.

[0040] The terms "first" and "second" are used for descriptive purposes only, and do not refer to the limitation of time sequence, quantity, or importance. They cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features, but are only for distinguishing one technical feature from another technical feature in the technical solution. Therefore, the features defined as "first" and "second" can explicitly or implicitly include one or more of the features. In the description of the utility model, the meaning of "multiple" is two or more than two (that is, more than two), unless otherwise clearly and specifically stipulated. Similarly, the qualifiers similar to "one" appearing in the text do not refer to the limitation of quantity, but describe technical features that have not appeared in the previous text. Similarly, unless it is a noun modified by a specific quantitative quantifier, the text should be regarded as including both singular and plural forms, and the technical solution can include both singular and plural technical features. Similarly, modifiers similar to "approximately" and "approximately" that appear before the numerals in the text usually include the number itself, and their specific meanings should be understood in conjunction with the context.

[0041] In the support structure 6, the first connecting wall 61 is welded to one end of the annular stop wall 4 of the protective cover 1 in the axial direction X0, and has a first connecting portion 613 protruding outward in the radial direction R0 and exceeding the annular stop wall 4. Figure 4 The first connecting wall 61 can be a baffle, which is welded to one end 40 of the annular stop wall 4. The radially inner part of the annular stop wall 4 constitutes the side baffle wall 51, and the part exceeding the annular stop wall 4 (that is, on the outer side of the annular stop wall 4) constitutes the first connecting portion 613.

[0042] The second connecting wall 62 extends outwardly from an outer surface of one pipe 30 in the radial direction R0 and has a second connecting portion 623 at a radially outer end.

[0043] The intermediate connecting wall 63 has an outer connecting portion 631 and an inner connecting portion 632 located on the outer side and the inner side, respectively, in the radial direction R0. The first connecting portion 613 and the second connecting portion 623 are detachably connected to the outer connecting portion 631 and the inner connecting portion 632, respectively, by fasteners 81 and 82. By removing the fasteners 81 and 82, the protective cover 1 can be easily detached from the pipe 30, so that the protective cover 1 can be moved.

[0044] See also Figure 3 and Figure 5 The first connecting wall 61, the second connecting wall 62 and the middle connecting wall 63 are all fan-shaped plates. This structure can make the strength higher.

[0045] Figure 4In the figure, the middle connecting wall 63 has a straight plate portion 630 extending perpendicularly to the axial direction X0. The outer connecting portion 631 of the middle connecting wall 63 is a part of the straight plate portion 630, and thus, the outer connecting portion 631 extends perpendicularly to the axial direction X0. The fastener 81 connecting the first connecting portion 613 and the outer connecting portion 631 passes along the axial direction X0. It should be understood that the use of "along", "perpendicular", "parallel", etc. in describing directions herein requires that the object has a component in a direction in a strict mathematical sense, preferably, an angle within 20°, or even within 5°, with the direction in a strict sense.

[0046] The inner connecting portion 632 of the intermediate connecting wall 63 is bent relative to the straight plate portion 630 and extends along the axial direction X0. The second connecting portion 623 of the second connecting wall 62 corresponds to the inner connecting portion 632 and extends along the axial direction X0. The fastener 82 connecting the second connecting wall and the inner connecting portion 632 passes along the radial direction R0. The above arrangement is particularly convenient for disassembly and assembly.

[0047] Continue to see Figure 4 The inner connection portion 632 is located on the side opposite to the butt flange 20 relative to the straight plate portion 630 in the axial direction X0. This arrangement is particularly convenient for operators to perform assembly and disassembly.

[0048] The depth of the cylindrical wall constituting the annular stop wall 4 (that is, the dimension of the annular stop wall 4 in the axial direction X0) can be about three to four times the axial dimension of the docking flange 20. The annular stop wall 4 can be arranged symmetrically relative to the docking seam 201 of the docking flange 20 in the axial direction X0. The bottom section periphery 41 can be the lower half of the overall periphery of the cylindrical wall constituting the annular stop wall 4. The above arrangement enables the protective assembly 10 to have good anti-leakage and anti-splashing effects.

[0049] Figure 1 In the embodiment, the protection assembly 10 may further include an alarm system 7. The alarm system 7 may include a temperature sensor 71 and an alarm 72. The temperature sensor 71 is disposed at the inlet end 21 of the liquid receiving pipe 2, and the alarm 72 sends an alarm signal according to a temperature sensing signal of the temperature sensor 71.

[0050] The temperature sensor 71 can be various temperature probes, such as contact type or non-contact type, such as thermal resistors or thermocouples. The alarm 72 can also be various alarm devices, such as mechanical or electronic types, such as sound and light or screen display types. For example, if the temperature detected by the temperature sensor 71 is lower than a predetermined threshold, the alarm 72 sends an alarm signal. By arranging the temperature sensor 71 at the bottom of the protective cover 1, combined with the alarm 72, liquid leakage can be monitored and the leakage can be handled in time.

[0051] The above protection assembly confines the cryogenic liquid to the bottom of the protection cover without causing any damage to the cold box steel structure. It is safer and less costly. Moreover, the above protection assembly is very easy to disassemble and assemble. By removing fasteners such as bolts and nuts, the supporting structure, especially the middle connecting wall, can be easily removed from both sides, and then the protection cover can be removed from the flange structure. On-site operators can easily re-tighten the docking bolts of the docking flange to prevent further leakage. The operator can see whether there is a leak by observing the situation near the plug of the liquid receiving pipe. By setting a temperature sensor, an automatic alarm can be set.

[0052] Unless clearly indicated to the contrary, each aspect or embodiment defined herein may be combined with any other aspect or embodiments. In particular, any feature indicated as preferred or advantageous may be combined with any other feature indicated as preferred or advantageous.

[0053] The present specification only describes the preferred specific embodiments of the present invention. The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Any technical solutions that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention should be within the scope of the present invention.

Claims

1. A protective assembly for an air separation cold box, wherein two pipes connected by a butt flange are arranged in the box space surrounded by the box wall of the air separation cold box, and the butt flange defines a circumferential direction and an axial direction, and is characterized in that: The protection component comprises: A protective cover is detachably connected to the outside of the two pipes and comprises an annular stop wall and an axial stop member, wherein the annular stop wall surrounds the docking flange in a full circle, and the axial stop member comprises two side stop walls respectively connected to both sides of the annular stop wall in the axial direction; a liquid receiving pipe, wherein the inlet end of the liquid receiving pipe is opened in the annular stop wall, the outlet end of the liquid receiving pipe passes through the box wall and extends out from the box wall, and the outlet end is lower than the inlet end, whereby the liquid leaking from the docking flange is stopped by the annular stop wall and the axial stopper and then flows out of the box wall through the liquid receiving pipe; and The plug is detachably arranged at the outlet end of the liquid receiving pipe located outside the box wall, and blocks the outlet end.

2. The protection assembly according to claim 1, characterized in that: The docking flange also defines a radial direction; The annular stop wall is a cylindrical wall with openings at both ends. The annular stop wall has a bottom section periphery including a lowest point at each end. The side stop wall extends radially inwardly from the bottom section periphery.

3. The protection assembly according to claim 2, characterized in that: The protrusion height of the side baffle wall is set to allow the annular stop wall with the side baffle wall to move axially over the docking flange; The height of the protrusion is above 1 cm.

4. The protection assembly according to claim 2, characterized in that: The depth of the cylindrical wall is three to four times the axial dimension of the docking flange; The annular stop wall is symmetrically arranged relative to the butt joint of the butt flange in the axial direction; The bottom section periphery is the lower half of the overall periphery of the cylindrical wall.

5. The protection assembly according to claim 1, characterized in that: The protection assembly further comprises a supporting structure, and the protection cover is detachably connected to the outside of the two pipes through at least two of the supporting structures; The supporting structure includes a first connecting wall, a second connecting wall and an intermediate connecting wall, wherein the first connecting wall is fixedly connected to the protective cover, the second connecting wall is fixedly connected to one of the two pipes, and the intermediate connecting wall is detachably connected to the first connecting wall and the second connecting wall, respectively.

6. The protection assembly according to claim 5, characterized in that: The docking flange also defines a radial direction; In the support structure, the first connecting wall is welded to one end of the annular stop wall of the protective cover in the axial direction, and has a first connecting portion protruding outward in the radial direction and exceeding the annular stop wall; The second connecting wall extends radially outward from the outer surface of the one pipe and has a second connecting portion at the radial outer end; The intermediate connecting wall has an outer connecting portion and an inner connecting portion respectively located at the outer side and the inner side in the radial direction, and the first connecting portion and the second connecting portion are detachably connected to the outer connecting portion and the inner connecting portion respectively through fasteners.

7. The protection assembly according to claim 6, characterized in that: The intermediate connecting wall has a straight plate portion extending perpendicularly to the axial direction, the outer connecting portion of the intermediate connecting wall is a part of the straight plate portion, and a fastener connecting the first connecting portion and the outer connecting portion passes through the axial direction; The inner connecting portion of the intermediate connecting wall is bent relative to the straight plate portion and extends axially, the second connecting portion of the second connecting wall extends axially corresponding to the inner connecting portion, and the fastener connecting the second connecting wall and the inner connecting portion passes radially.

8. The protection assembly according to claim 7, characterized in that: The inner connection portion is located on a side opposite to the mating flange relative to the straight plate portion in the axial direction.

9. The protection assembly according to claim 1, characterized in that: It also includes an alarm system, which includes a temperature sensor and an alarm. The temperature sensor is arranged at the inlet end of the liquid receiving pipe, and the alarm sends an alarm signal according to the temperature sensing signal of the temperature sensor.

10. An air separation cold box, characterized in that: Comprising the protection component as claimed in any one of claims 1 to 9.

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