CN110268215B

CN110268215B - Enclosure for an apparatus for separating a gaseous mixture by distillation and separation apparatus comprising such an enclosure

Info

Publication number: CN110268215B
Application number: CN201880011182.9A
Authority: CN
Inventors: R·库尔茨; P·阿哥尼; B·达维迪安; C·莱克斯; D·皮萨诺; A·法夫尔
Original assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Current assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Priority date: 2017-01-10
Filing date: 2018-01-10
Publication date: 2021-09-03
Anticipated expiration: 2038-01-10
Also published as: WO2018130157A1; CN110268215A

Abstract

The invention relates to an enclosure for an apparatus for separating gaseous mixtures at cryogenic temperatures below ambient, said enclosure being designed to accommodate at least one element of said apparatus which must operate at temperatures below 0 ℃, preferably below-50 ℃ or even at cryogenic temperatures, said enclosure being in the form of a caisson and comprising at least one frame comprising longitudinal pillars (3) and beams and stays interconnecting said pillars, at least one means (13, 15, 17) for conveying material and/or electricity, light or information being at least partially housed in said at least one pillar.

Description

Enclosure for an apparatus for separating a gaseous mixture by distillation and separation apparatus comprising such an enclosure

Technical Field

The present invention relates to an enclosure for an apparatus for separating a gaseous mixture by distillation at sub-ambient or even cryogenic/cryogenic temperatures.

Background

The enclosure of the device for separating gaseous mixtures, in particular air, by cryogenic temperatures below ambient accommodates at least one element of the device which must operate at temperatures below 0 ℃ or even at cryogenic temperatures. The enclosure comprises at least one frame comprising longitudinal struts and beams interconnecting the struts.

Typically, the frame is that of an enclosed caisson having at least four side walls. It may also include a ceiling and/or a floor. In the operating condition, the closed caisson houses thermal insulation (thermal insulation/insulating material) in contact with at least one of the walls and/or with the elements that must operate at a temperature lower than ambient.

In contrast, it is also known to provide a frame that houses and/or supports at least one enclosed caisson as described above. Goldstone et al, "Tonnage Nitrogen Generation for Oil and Gas Enhanced Recovery in the North Sea," Proceedings of the Gas Processors associates, 1992, show in FIG. 6 the framework of such a closed caisson that houses and supports the elements of an air separation plant. The frame thus forms an open structure, making it possible to introduce a closed caisson containing at least one separation column, another caisson containing another element that must operate at a temperature lower than ambient, for example a heat exchanger designed to cool the gaseous mixture to be separated in the column.

An apparatus for separating a gaseous mixture, such as air, using cryogenic distillation comprises components operating at ambient temperature and components operating at sub-ambient temperatures, that is to say at temperatures below 0 ℃ or even at low temperatures. Elements operating at sub-ambient temperatures are held in an insulation enclosure commonly referred to as a "cold box" and filled with insulation material(s) (perlite, rock wool, vacuum insulation panels, etc.). These enclosures are typically in the form of rectangular parallelepiped caissons, having a metal frame comprising vertical struts interconnected by horizontal beams. Four side walls of the caisson are coated with metal plates. Elements operating at ambient temperature may also be placed in other frames to facilitate their transportation or sound insulation, or to hold them in place above the ground.

The insulation enclosures are not completely sealed from the outside air and, for thermal efficiency reasons and safety reasons, a continuous flow of gaseous nitrogen flushes the interior of these "cold boxes".

It is known to feed gaseous nitrogen from A distillation column into an insulation by means of A distributor placed in the middle of the insulation stack, as shown in WO-A-2004015347.

In order to maintain a dry atmosphere in the insulation of the cold box, nitrogen with an oxygen content below 5% from the inert gas network of the plant is generally utilized by creating a slight overpressure with respect to the atmospheric pressure in order to avoid any humid air entering the insulation. The fluid must be completely dry and de-oiled. In fact, any moisture entering the cold box will degrade the thermal properties of the insulation (perlite). Furthermore, the entry of air (even dry air) carries the risk of condensation of oxygen-enriched air once the temperature of the insulation (close to the cryogenic equipment) is below the dew point of the air. This phenomenon then poses the risk of ignition and/or explosion due to any element that is flammable in oxygen-enriched air.

In the main cabinet of the cold box, it is also necessary to ensure that the atmosphere is continuously refreshed:

so as to exhaust the ambient air and insulate it after opening.

In order to dilute and expel any air that has entered.

The hourly flow to be considered for inerting must be such that the atmosphere of the cold box can be periodically refreshed.

The frame designed to accommodate at least one element of the air separation plant at a temperature below or not below ambient temperature may be a metal structure consisting of struts, beams or joists. These pillars, beams or joists may be open section members consisting of H-, I-, L-or U-section profiles or closed section members consisting of round or rectangular section profiles, e.g. square section profiles. The purpose of these profiles is not to hold the structure around the element and to support the cladding of the cold box, such as a metal plate. It is also possible to design an assembly called a "truss node" which comprises a closed section in combination with an open section.

The frame itself may form the frame of an enclosed caisson in which at least one element of the apparatus is to be accommodated, or at least one such enclosed caisson may be supported and/or accommodated.

The frame may for example comprise four vertical posts, each of which is a rectangular section profile, thereby defining a rectangular parallelepiped space within each of the four posts. Four struts are arranged parallel to each other, the vertical axis of each strut defining one of the four corners of the frame. Thus, the frame has a rectangular, sometimes square, cross-section.

The four struts are interconnected at several different heights by horizontal beams.

We propose to use this empty space in and/or on the profile for transporting certain particulate materials, such as perlite or other powders, or for flushing the cold box with fluids, such as instrument air or nitrogen, or for housing cables for transmitting power, light or information.

Preferably, the interior of the enclosure or a user of the enclosure requires one or more fluids, or particulate materials, or electricity, light or information.

The unit for producing gas, separation or purification may comprise, inter alia, at least one rotating machine (motor, compressor, turbine, pump, valve actuator, etc.), at least one reservoir (storage device, phase separator, etc.) and pipes. These elements may be housed in and/or supported by a solid metal frame or a structure made of concrete or a combination of both. Thus, the compressor, which may or may not be combined with other elements such as a booster compressor and a cooler, may be mounted in a metal frame.

FR- A-3017443 discloses the use of flushing nitrogen gas for certain pipes attached to the structure.

FR- A-2769656 describes A metal framework having A substantially parallelepiped shape, comprising four longitudinal struts connected by diagonal braces and beams on each large side of the truss.

EP- ｃA-1041353 describes the use of I-beams to secure the column to the cold box.

WO-A-2010/067253 describes A cold box containing A column with four vertical legs connected to an insulated enclosure containing pipes and valves but not A nattA.

FR- A-2946075 describes an enclosure according to the preamble of claim 1, in which the frame is fitted with A duct as an accessory to the tower. Frames have been used for many years to support cold boxes but to our knowledge, frames have never been suggested for transporting material or energy into and out of cold boxes. Furthermore, many of the conduits within the cold box cannot be considered to be column fittings, such as conduits for sending purge gas to the insulation.

Disclosure of Invention

According to one subject of the invention, an enclosure is provided for an apparatus for separating gaseous mixtures, in particular air, by distillation at subambient cryogenic temperatures, designed to accommodate at least one element of the apparatus which must operate at temperatures below 0 ℃, preferably below-50 ℃ or even at cryogenic temperatures, in the form of a caisson and comprising at least one frame comprising longitudinal pillars and beams and stays interconnecting the pillars, possibly externally equipped with at least one guardrail comprising at least one bar, wherein

a) The at least one strut and/or the at least one beam and/or, where relevant, the at least one bar constitutes a device for conveying material, and/or

b) At least one means for conveying material and/or electricity, light or information is at least partially housed in the at least one pillar and/or the at least one beam and/or, where relevant, the at least one bar.

According to other optional aspects:

the frame is the frame of a closed caisson having at least four side walls and possibly a ceiling and possibly a floor, and designed to contain insulation in contact with at least one of the walls and/or with the elements.

-said frame houses and/or supports at least one closed caisson having at least four side walls and a ceiling, and housing insulation in contact with at least one of said walls and/or with said elements.

The pillars and/or beams and/or bars are hollow and the conveying means are conveying pipes housed in the pillars and/or beams and/or bars.

The pillars and/or beams and/or bars comprise an enclosed space connected to the material inlet and the material outlet so as to allow material to be transported from the inlet to the outlet, the material being in contact with the enclosed space.

The enclosure is designed to be filled with insulation and the at least one conveying means is a material conveying duct that emerges inside the enclosure.

The material delivery means is connected to a source of gaseous nitrogen or air and/or to a source of insulating particulate material designed to act as insulation, the source being located outside the enclosure.

-at least one of said struts is one of four main longitudinal struts located at four corners of the enclosure.

Said at least one conveying means is an electrical or optical cable or a conduit for fluid coming from or intended for the enclosure, which cable or conduit is preferably connected with said element.

The at least one delivery device is a pipe connected to a source of dry air, which pipe is connected to the instrumentation of the enclosure.

The enclosure houses an element and this element is at least one column for distilling off gas from air, a storage device, a heat exchange line (which is possibly used for cooling air intended for distillation) or a set of pipes that must operate at temperatures below 0 ℃.

-said element is at least one column for distilling a gaseous or liquid product from a gaseous mixture, such as air, and said material is at least a part of the gaseous mixture or the gaseous or liquid product.

The at least one pillar and/or the at least one beam and/or, where relevant, the at least one bar constitute means for conveying particulate matter to be used for filling the enclosure and/or means for feeding instrument air or purge nitrogen to the interior of the enclosure.

The at least one device for conveying material is connected to an element, such as a tower, contained within the enclosure, in order to supply gas thereto and/or remove gas therefrom.

-the at least one means for transporting material is connected to elements within the enclosure other than the tower.

The enclosure contains an element and the element is at least one column for distilling a gaseous or liquid product from a gaseous mixture, the material being at least a part of the gaseous mixture or the gaseous or liquid product.

According to another subject of the present invention, there is provided an air separation plant comprising at least one enclosure as described above, the plant comprising at least one distillation column and at least one heat exchanger and/or at least one rotary machine and/or actuator and/or sensor, and said at least one enclosure housing at least one of said distillation column and/or at least one heat exchanger and/or at least one rotary machine and/or actuator and/or sensor.

The actuator may be an actuator of a valve or a controller.

The apparatus may comprise a further enclosure for accommodating at least one other element of the apparatus, which element must operate at a temperature between 0 ℃ and 100 ℃ or above 100 ℃, in the form of a caisson and comprising at least one frame comprising longitudinal pillars and beams and stays interconnecting the pillars, possibly externally equipped with at least one guardrail comprising at least one bar, wherein

a) The at least one strut and/or the at least one beam and/or, where relevant, the at least one bar constitute means for conveying material, and/or

It proposes that:

-using the closed hollow pillar of the cold box to blow and/or remove powdery insulation material from the installed cold box after the stage of installing the cold box,

using open-section or closed-section struts of the frame, for example struts of a cold box, to receive electrical or optical cables, for example for instruments and/or to control processes or pipes for transporting fluids or pulverulent materials,

using a bar of the guardrail, for example a bar attached to a wall of the enclosure, to receive at least one optical or electrical cable,

using a bar of the guardrail, for example a bar attached on a wall of the enclosure, to convey gaseous nitrogen or air inside the hollow bar or inside a duct at least partially housed in the bar, wherein the fluid may be air for the instrument, nitrogen for inerting the cold box, or gas for moving the actuator of the pneumatic valve.

It is envisaged that particulate material (e.g. perlite) or a gas such as flushing nitrogen or instrument air is fed directly into the hollow pillar so that the pillar itself acts as a material transport conduit.

In this case, the strut comprises an inlet by means of which the particulate material or gas can be conducted from the exterior of the strut to the interior of the strut and an outlet by means of which the particulate material or gas can be conducted from the interior of the strut to the interior of the enclosure. The inlet and/or the outlet may be a simple hole in the wall of the pillar.

Alternatively, the particulate material or gas may be conveyed through a conduit located in the space inside the hollow profile. The conduit emerges outside the strut and the enclosure so as to allow the entry of gas or particulate material, and also emerges inside the enclosure so as to enable the gas or particulate material to be fed therein.

A plurality of gases of different composition and/or pressure may circulate in the space inside the hollow profile, in a plurality of pipes.

The profile itself can be used both as a pipe and as a pipe in the space inside the hollow profile. For example, the cold box can be filled with perlite by feeding it into the profile without entering the pipe, and the same profile is used to convey the gas which is fed into the pipe in the space inside the hollow profile.

The profiles used may extend vertically, horizontally or transversely.

Furthermore, the invention has a specific synergistic effect with the modular structure around the base when the base consists of open or closed section beams as described in FR 3017939. This modular approach to an ASU allows for components of the ASU that may be transported to the site in a package, container, or module. These containers are mounted on a three-dimensional support base made of posts, beams or joists. They may be mounted horizontally or vertically. The base may house electrical cables or I & C cables, or may carry fluids such as instrument air.

An aspect of the invention provides a method of providing powdered insulation to an enclosure as described above, wherein the powdered insulation is fed into the enclosure by:

a) conveying the powdered insulating material, and/or the powdered insulating material, at least partially via the at least one hollow column and/or the at least one hollow beam and/or the at least one hollow rod which, in the case in point, constitutes a means for conveying material

b) The powdered insulation material is conveyed at least partly via a pipe for conveying the material, which pipe is at least partly received in the at least one pillar and/or the at least one beam and/or, in the case in point, the at least one bar.

A further aspect of the invention provides a method of removing powdered insulation from an enclosure as described above, wherein the powdered insulation is removed from the enclosure by:

Drawings

The present invention will be described in more detail with reference to the accompanying drawings. Fig. 1, 2 and 3 show an enclosure of an apparatus for separating a gaseous mixture, in particular air, by cryogenic temperatures below ambient, designed to house at least one element of the apparatus which must operate at temperatures below 0 ℃, preferably below-50 ℃.

Fig. 1A, 1B, 1C, and 1D illustrate the "truss node" of fig. 1 in more detail, and fig. 3A, 3B, and 3C illustrate the "truss node" of fig. 3 in more detail. Fig. 4 shows details of an enclosure according to the invention, such as a guard rail and its bars, and fig. 5, 6 and 7 show sections through various struts used in an enclosure according to the invention.

Detailed Description

The figures illustrate various types of posts in which the device for transporting material may be received.

In each of these profiles, a gas pipe, perlite conveying pipe or cable can be received in the inner space of the profile.

Fig. 1 shows a frame for an enclosure of a separation apparatus prior to installation of an element to be insulated, such as a distillation column or a heat exchanger. The frame comprises four vertical pillars 3 interconnected by horizontal beams and stays.

As shown in fig. 1A, 1B, 1C, and 1D, the inside of each pillar forms a space of a rectangular-section, which may be square-section. The space can be used for transporting various substances.

In particular, perlite or another insulating material may be injected into at least one of the posts, for example near the bottom of the post, and once the post has been clad with a panel to seal it may be withdrawn from the post near the top in order to distribute the perlite into the frame. Preferably, the perlite exits from at least two or even all four of the struts so as to allow better distribution of the powder.

Perlite may also pass through spaces inside the stays and/or beams.

The same technique may also be used to remove insulation within the enclosure to at least partially or even completely empty the enclosure. Insulation passes through the structure (struts, beams or stays) and the method can be used to remove insulation in specific areas of the cold box (e.g. for removing perlite from the top of the cold box) by making openings in the frame.

Dry air or dry gaseous nitrogen from outside the frame can also be conveyed through the frame by passing from the inner space of at least one or even all of the pillars to flush the insulation. This dry air or gaseous nitrogen acts as a purge gas to ensure that cold gas does not accumulate within the insulation.

Sending dry air through the posts already used to transport the perlite makes it possible to drain any perlite that is trapped in the posts and thus avoid waste.

The same or another dry air may be used as the instrument gas that has passed through the interior of the strut, for example to actuate a valve.

The interior space of the at least one strut and/or beam and/or stay may also accommodate at least one conduit for a liquid or gas, e.g. a distillation product or a fluid fed to the distillation column, e.g. originating from or being directed to an element inside the enclosure.

The gas or liquid does not have to be contained in the conduit but may be in direct contact with the interior of the strut.

The space inside the at least one post may also accommodate at least one electrical or optical cable. The cable may for example supply electrical power for external illumination of the enclosure or for powering a rotating machine or an actuator or sensor accommodated in the frame.

Fig. 1A shows in more detail the coupling between the struts and shows that all of these metal elements are hollow. Fig. 1B is a cross section through fig. 1A. FIG. 1C shows the junction between the bottom of the post and the brace or beam at one bottom corner of the frame. Fig. 1D is a cross-section through fig. 1C.

The profiles, which make up the metal structure known as commercial steel bars (merchant bar), are drawn, bent or reshaped in the case of non-standard iron. They have a rectangular cross section so as to form a box ideal in terms of mechanical strength. However, they are limited in mechanical strength and high in cost.

The reshaped welded profile is a profile manufactured according to specific structural requirements, using thick steel plates welded together. It is also possible to use metal plates of different thicknesses for the web and the flange and to form curved profiles, but the design of these profiles requires a great deal of effort to obtain only a square shape.

Finally, a novel type of stud that has particular advantages to the present invention is a reshaped welded profile. This novel form of profile combines the advantages of the box in terms of calculation and of the plate in terms of extrusion time. It consists of two angle irons of different sizes assembled mirror-wise by means of two corner welds. This assembly of two distinct components accommodates many variations: thickness of the profile, choice of drawn or bent profile, versatility of the system for connection with the metal sheet. Furthermore, it facilitates the installation of the transport device.

Fig. 2 shows a section through a frame accommodating two elements K1, K2, each of which may be a distillation column or a storage unit or a phase separator. The element is surrounded by four walls 2 of the enclosure 1, with four struts 3 forming the corners.

Figure 3 shows a frame constructed using I, U, H or T-section metal profiles. In this case, the material to be transported is transported in a pipe or cable. One or more conduits and/or one or more cables may be housed in the hollow of the post 7 or stay.

Fig. 3A and 3B show details of the frame, and fig. 3C is a cross-section through fig. 3B.

Figure 3 shows a guard rail comprising at least one bar at the top. Similar guardrails are typically mounted on the exterior of the enclosure at intermediate elevations, for example to allow access to the interior and to the instrumentation. These barriers must be illuminated. Since the rods used may comprise an inner space, this space may house optical and/or electrical cables and/or pipes for gas or liquid and/or pipes for perlite.

The struts of fig. 1 and 3 may be used to drain rain water from the roof of the enclosure or from a platform attached on the side of the enclosure.

Figure 4 shows in more detail the guard rail of a person on the platform at mid-height of the protective enclosure. Through a flight of stairs to the railing. The guardrail comprises bars as hollow vertical posts 103 and hollow horizontal bars 113.

The hollow rod may constitute a means for conveying material and/or electricity, light or information.

In addition, at least one means for conveying material and/or electrical power, light or information is at least partially housed in at least one bar of the guardrail.

Fig. 5 shows a hollow strut belonging to one of fig. 1 to 4, wherein two

conduits

13, 15 are provided in the interior of the strut. The remaining space may be filled with material or may be used for transporting material, such as gas. The

conduits

13, 15 may each be conduits for materials, electricity, light or information.

Fig. 6 and 7 show a metal profile 7 with an I-shaped cross section and an H-shaped cross section, respectively. Both spaces formed on both sides of the profile 7 can receive at least one

pipe

13, 15, 17. Each conduit may carry material or electricity or light or information.

In case the enclosure is designed to be filled with insulation, one of the

ducts

13, 15, 17 of fig. 5 to 7 may be a means for conveying insulation to be conveyed from the outside to the inside of the enclosure. The conduit is thus a conduit for transporting material present inside the enclosure. Preferably, several or even all of the pillars will accommodate ducts for transporting insulation in order to properly distribute the insulation within the enclosure. Hollow pillars as shown in fig. 5 may be used to transport insulation from the outside to the inside of the enclosure.

The invention relates in particular to a device for separating air, comprising an enclosure designed to house at least one element of the device that must operate at temperatures below 0 ℃, preferably below-50 ℃ or even at cryogenic temperatures, in the form of a caisson and comprising at least one frame usable to convey materials and/or electricity, light or information.

The apparatus for separating air may comprise at least one further enclosure containing at least one further element of the apparatus which must operate at temperatures above 100 ℃, in the form of a caisson and comprising at least one frame which may be used to convey materials and/or electricity, light or information. The element may for example be an air purification unit for removing carbon dioxide and/or water contained in the air.

The hollow pillar or beam or bar may simultaneously be used for transporting material (e.g. gas, liquid or powdery material) and possibly additionally contain at least one conduit for transporting material, electricity, light or information.

Claims

1. An enclosure (1) for an apparatus for separating gaseous mixtures by distillation at sub-ambient cryogenic temperatures, designed to accommodate at least one element (K1, K2) of the apparatus which must operate at temperatures below 0 ℃, in the form of a caisson and comprising at least one frame comprising longitudinal pillars (3) and beams (7) interconnecting the pillars and braces interconnecting the pillars, the enclosure being externally equipped with at least one guardrail comprising at least one bar (103, 113), wherein

a) The at least one strut and/or the at least one beam and/or the at least one bar constitute means for conveying material, the strut (3) and/or the beam (7) and/or the bar (103, 113) are hollow and the means for conveying material are conveying pipes housed in the strut and/or the beam and/or the bar, and/or

b) At least one means (13, 15, 17) for conveying material and/or electricity, light or information is at least partially housed in the at least one pillar and/or the at least one beam and/or the at least one bar.

2. The enclosure according to claim 1, wherein the enclosure is a closed caisson and the frame is a frame of a closed caisson, having at least four side walls (2) and a ceiling and a floor, and being designed to contain insulation in contact with at least one of the walls and/or with the elements.

3. The enclosure of claim 1, wherein the enclosure is a closed caisson and the frame houses and/or supports the closed caisson, the caisson having at least four side walls and a ceiling and housing insulation in contact with at least one of the walls and/or with the elements.

4. An enclosure according to any of claims 1-3, wherein the pillars (3) and/or the beams (7) and/or the bars (103, 113) comprise an enclosed space connected with a material inlet and a material outlet, so as to allow material to be transported from the inlet to the outlet, the material being in contact with the enclosed space.

5. An enclosure according to any one of claims 1-3, wherein the enclosure (1) is designed to be filled with insulation and the at least one means for conveying material is a material conveying conduit present inside the enclosure.

6. The enclosure according to claim 5, wherein said means for conveying the material is a conduit (13, 15, 17) connectable to a source of gaseous nitrogen or air, the source being external to the enclosure.

7. The enclosure according to claim 5, wherein said means for conveying material is a pipe (13, 15, 17) connectable to a source of particulate insulation material designed to act as insulation, the source being located outside the enclosure.

8. The enclosure of any one of claims 1-3, wherein at least one of the struts is one of four main longitudinal struts located at four corners of the enclosure.

9. An enclosure according to any one of claims 1-3, wherein the at least one means (13, 15, 17) for conveying material is a conduit connectable to a source of dry air, the conduit being connectable to an instrumentation device of the enclosure.

10. An enclosure according to any one of claims 1-3, wherein the at least one means (13, 15, 17) for conveying material is connected to an element housed within the enclosure so as to provide gas thereto and/or remove gas therefrom.

11. The enclosure according to any of claims 1-3, wherein the at least one means (13, 15, 17) for transporting material is connected to an element within the enclosure other than a tower.

12. The enclosure of any one of claims 1-3, wherein the enclosure houses an element and the element is at least one column (K1, K2) for distilling a gaseous or liquid product from a gaseous mixture and the material is at least a portion of the gaseous mixture or the gaseous or liquid product.

13. The enclosure of claim 1, wherein the gaseous mixture is air.

14. The enclosure of claim 1, wherein the element must operate at a temperature below-50 ℃.

15. The enclosure of claim 1, wherein the element must operate at cryogenic temperatures.

16. The enclosure of claim 10, wherein the at least one means (13, 15, 17) for conveying material is connected to a tower housed within the enclosure.

17. An air separation apparatus comprising at least one enclosure according to any one of the preceding claims, the apparatus comprising at least one distillation column (K1, K2) and at least one heat exchanger and at least one rotary machine and/or actuator and/or sensor, and the at least one enclosure housing at least one of the distillation column and/or at least one heat exchanger and/or at least one rotary machine and/or actuator and/or sensor.

18. The apparatus according to claim 17, comprising a further enclosure for housing at least one other element of the apparatus, which element must operate at temperatures above 100 ℃, in the form of a caisson and comprising at least one frame comprising longitudinal pillars (3) and beams and stays interconnecting the pillars, said enclosure being externally equipped with at least one guardrail comprising at least one bar (103, 113), wherein

a) The at least one support and/or the at least one beam and/or the at least one bar form a device for transporting material, and/or