CN1221641A

CN1221641A - Plant for separation of gases by adsorption, and use for treatment of air flows

Info

Publication number: CN1221641A
Application number: CN 98118691
Authority: CN
Inventors: 克里斯蒂昂·莫纳雷奥; 菲利普·安德列亚尼; 让-迈克·贝洛; 让-巴提斯特·德隆
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: 1997-08-26
Filing date: 1998-08-25
Publication date: 1999-07-07

Abstract

A plant for the separation of gases by adsorption, which is of the PSA type, includes, in a container (1) of vertical axis, at least one annular bed of particulate material (5, 6) supported on a lower wall (9) which is itself supported by a perforated prismatic wall (11) bearing on a domed end (2) of the container. A lower wall (9), advantageously in the form of a very wide inverted V (9A, 9B), has no part forming an angle ( alpha , beta ) in excess of 15 DEG with the horizontal. The plant is useful in the separation of gases from air.

Description

Device by separating gases by adsorption and handle the purposes of air stream

The present invention relates to device by separating gases by adsorption, more particularly PSA or VSA type (pressure/fluctuations of vacuum type suction-operated), be included in and comprise central gas and side gas passage in the container that has vertical direction and arch lower end usually, at least one vertical axis, be limited to the annular seating volume of a special material of bottom by lower wall, and at least one is provided with the first prismatic wall between arch end and the lower wall of being in hole.

Such separator is handled big throughput with quick circular order, proposes the problem of relevant gas circulation and distribution, and these problems as in this example, further worsen by meeting in the device of adsorbent in gas level.In addition, annular seating is by the annular volume weight that must support special material, especially when repressurize that produces the pressure loss or depressurization steps, by acting on the formed power of this wall either side pressure differential, and may come spacing by the lower wall of the formed power of device for filling that acts on special material volume upper surface.

This type of gas fractionation unit is described in 759,320 files at the EP-A-0 with applicant company name.In this document, be that the lower wall on plane has very big thickness so that support the volume of special material, the space between space in this volume and lower wall and the container arch end comprises that porous barrier is in order to make gas stream homogenising in these spaces.

After fully studying, the shape that applicant company observes the adsorption site lower wall has significant effects to the correct distribution that the annular volume gas by special material flows, simultaneously it can produce defective especially in gas flow distribution, and this defective is not limited to adjacent domain but has actual significant effects at the volume of special material with interior.

Therefore applicant company is verified, remove beyond the mechanical strength that is proposed, end wall should not be arch and should be very little taper and the angle that forms without any part and horizontal direction above 15 °.With the shape of this pattern, in order to reach necessary mechanical strength, file may provide the thick end wall that is bearing on the conveyance conduit of center as described above.But, caused overweight problem, use heavy wall to strengthen footpath thermotropism conduction, this has also changed the Temperature Distribution of adsorption site adjacent domain simultaneously, therefore adsorption site operates under different state of temperatures, those states are to form at these center heat insulating part, therefore the optimal operation that hinders device and reached, also it is contemplated that reinforcement radial rigidity below lower wall, but this ribs that studies show that this type structure carries out has been changed flowing of container lower gas significantly, produced preferential circulation canal towards the side gas passage.

Therefore purpose of the present invention just provides and novel carries out the structure of the device that gas separates with suction-operated, this structural entity good rigidly and low cost of manufacture, and this novel structure makes it to obtain optimal gas with minimal energy consumption and distributes.

For this reason, according to an aspect of the present invention, the annular volume is supported on the side lower wall, and this wall neither one part surpasses 15 ° with the angle that horizontal direction forms, and this wall is by the prismatic wall supporting that is bearing on the arch end simultaneously.

According to a specific characteristic of the present invention, lower wall is inverted V-shaped can be supported on the interior space that limits the container bottom on the second prismatic wall internally simultaneously.

In the structure of this pattern, contrast with aforementioned document, wherein the following annulus of porous barrier has the function of unique equal oxidizing gases stream, lower wall has the profile and the thickness of optimization, acts on load on the lower wall by also being solid and rigidity and thick prismatic wall that finish supporting and liquid distributor double action herein is delivered to solid and following arcuate part rigidity of container.

Other features and advantages of the present invention will show from the description of following examples, but this embodiment provides with figure and do not mean any restriction, wherein:

Fig. 1 is the part schematic diagram according to the vertical section of gas fractionation unit first embodiment of the present invention; And

Fig. 2 is the partial view of the bottom of another optional embodiment of the present invention.

In following description and accompanying drawing, identical or similar elements has the identical label that suitably marks.

Accompanying drawing represents typically to be used to handle pressure oscillation absorption or the fluctuations of vacuum adsorption separation device that air flows, is used in particular for producing impure oxygen, comprise container 1, its geometry has a vertical rotating shaft line when being in working morphology, container has following arch end 2, comprise central gas 3 and biasing or side gas passage 4.The internal arrangement of container 1 has the annular volume of an absorbent particles 5, is typically zeolite, and a special material and put coaxial line central authorities annular seat 6, in order to keep water and carbon dioxide, be typically alumina.

Screen work 7 limits main seat 5 on circumference, this screen work radially separates with the circumference shell of container 1 inwards, and centre mount 6 is limited internally by an interior screen work or central distributor tube 8, the lower end of pipe 8 is fixed on the upper end that is fixed on the distributor tube 10 of bifurcated on the lower wall 9 with the supporting adsorbent simultaneously, pipe 10 lower end is fixed on the central gas 3, and seat 5 and 6 is by keeping and device for filling 20 limits at the top.

According to an aspect of the present invention, the following annular wall 9 of absorber supporting is relative approaching, the thickness that has is less than arch end 2, be typically less than half of the latter, remove be bearing on the diffuser tube 10 beyond, also by prismatic, be preferably cylindrical wall 11 supporting, its thickness is greater than wall 9, and this wall 9 is with diffuser tube 10 coaxial lines and be bearing on the arch end 2 of container 1.The interior space 12 of wall 11 below pipe 10 limits, gas passage aperture 4 leads to this space 12.

Prismatic wall 11 can be fixed on the end wall 9 and be supported on the end 2.As a kind of modification, wall 9 can be supported on the prismatic wall 11 simply, if absorber moves with non-perpendicular position, then inner body is by extending between the circumference shell 17 of container 1 and annulus wall 9, shown in 15 among Fig. 1, and/or between shell and screen work 7, extend, the plate shown in 16 among Fig. 1, radial support members centering and supporting.

Prismatic wall 11 forms many holes in its whole circumference with on its whole height, percent opening (ratio that the surface area in hole is long-pending with total theoretical surface of wall 11) is less than 60%, advantageously less than 30% and be typically between 4-10%.

In the embodiment shown in fig. 1, according to an aspect of the present invention, lower wall 9 is the inverted V-shaped of very wide opening, have the 9A of first of outer frustum of a cone outward-dipping from the horizontal by the α angle and interior frusto-conical portion 9B be inclined from the horizontal by the β angle inwards, according to an aspect of the present invention, angle α and β are no more than 15 ° and advantageously between 5 ° and 10 °.

As a kind of modification, as shown in Figure 2, the part 9A of outside can be the plane basically, and the part 9B of the inside keeps the downward conicity greater than 5 °.

From then on can also find out among Fig. 2, according to an aspect of the present invention, unless the supporting structure of lower wall 9 can be divided into similar described above but deflection 9A part periphery the prismatic wall 11 of porous and with the former coaxial line and basically atresia for quickening exhaust, center wall 13.

In this embodiment, side gas passage 4 is to limit between outer wall 11 and inwall 13 to the interior space 12 of its opening.

In a special embodiment, represented as Fig. 1, at the central lumen of center screen work the inside or distributor tube 8 part 14 that a coaxial line profile gradually opens is set centrally and evenly distributes on the whole height in annular seat 5 and 6 when promoting gas by them.

Device according to the present invention is mainly used in divided gas flow from air, particularly air of Sheng Chaning or impure oxygen.

Claims

1. carry out the device that gas separates with suction-operated, comprise, in container (1), has an arch lower end (2) that comprises central gas (3) and side gas passage (4), the annular volume (5 of at least one vertical axis, 6), at least one is limited to the annular volume of the special material of bottom by lower wall (9), and at least one first prismatic wall (11) that the hole is set between arch end (2) and lower wall (9), it is characterized in that: annular volume (5,6) be supported on the transverse end wall (9), this transverse end wall does not have a part to be supported by the prismatic wall (11) that is bearing on the arch end (2) simultaneously from the horizontal by the angle that surpasses 15 °.

2. device according to claim 1, the percent opening that it is characterized in that prismatic wall (11) is less than 60%.

3. device according to claim 2, the percent opening that it is characterized in that prismatic wall (11) is less than 30%.

4. device according to claim 3, the percent opening that it is characterized in that prismatic wall (11) is between 4% and 10%.

5. according to each the described device in the aforementioned claim, it is characterized in that lower wall (9) be inverted V-shaped (9A, 9B).

6. according to each the described device in the aforementioned claim, it is characterized in that lower wall (9) is supported on the second prismatic wall, space (12) in the first prismatic wall (11) limits an annular, side gas passage (4) feeds should interior space.

7. according to each the described device in the aforementioned claim, it is characterized in that thickness that horizontal lower wall (9) has thickness less than arch lower end (2).

8. according to each the described device in the aforementioned claim, it is characterized in that it comprises the centralising device (15,16) of radially arranged between container (1) and annular volume (5,6).

9. according to each the described device in the aforementioned claim, it is characterized in that comprising a cone-shaped diffuser (10) on the inward flange that central gas (3) is connected to lower wall (9).

10. use the purposes of handling air stream according to each the described device in the aforementioned claim.