Reactor for a catalytic process

Abstract

A reactor for a catalytic process comprising one or more catalyst beds has catalyst bed supports constructed as a grid comprising a plurality of cassettes (01), which are covered with easily removable screens (02). The down-time and service costs for the reactor are thereby lowered.

Claims

1. Reactor for a catalytic process with one or more catalyst beds of catalyst pellets, comprising a bottom support for each of said catalyst beds, the support is constructed as a grid comprising a plurality of cassettes, each cassette is covered by a permeable screen with apertures large enough to allow flow through of process fluid, but small enough to retain the catalyst pellets, wherein said screen is removably fastened to said cassette, wherein a majority of the screens in the reactor are rectangular and each screen is fixed to a cassette in each of its four corners by means of quick release means, enabling the screen to be fixed to or detached from the cassette by hand or by hand tools in less than 5 minutes.

2. Reactor according to claim 1, wherein the apertures of the screen each has an area of between 500 mm.sup.2 and 0.1 mm.sup.2.

3. Reactor according to claim 1, wherein the apertures of the screen each has an area of between 100 mm.sup.2 and 1 mm.sup.2.

4. Reactor according to claim 1, wherein the screen is made by woven wire mesh.

5. Reactor according to claim 1, wherein the screen is made by welded wires and rods.

6. Reactor according to claim 1, wherein the screen is made by a flat printed pattern.

7. Reactor according to claim 1, wherein the weight of the screen is below 100 kg.

8. Reactor according to claim 1, wherein the weight of the screen is below 25 kg.

9. Reactor according to claim 1, wherein the reactor is a hydroprocessing reactor, a hydrogenation reactor, a TIGAS reactor, or a methanation reactor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is further illustrated by the accompanying drawings showing examples of embodiments of the invention.

(2) FIG. 1 shows an isometric top view of the cassette with a screen according to an embodiment of the invention,

(3) FIG. 2 shows an isometric top view of the cassette without a screen according to an embodiment of the invention,

(4) FIG. 3 shows an isometric top view of a screen of a flat printed pattern type according to an embodiment of the invention, and

(5) FIG. 4 shows an isometric top view of a screen of a wire mesh type according to an embodiment of the invention.

POSITION NUMBERS

(6) 01. Cassette. 02. Screen. 03. Frame. 04. Quick release means. 05. Side. 06. Grid of cassette. 07. Threaded rod for quick release means. 08. Flat printed pattern apertures. 09. Supporting edge. 10. Fixing holes. 11. Wire mesh.

DESCRIPTION OF THE DRAWINGS

(7) A number of embodiments of the invention will be explained in more detail in the following with reference to the drawings.

(8) FIG. 1 shows an embodiment of a cassette 01 which is covered by a screen 02. Placed beside a plurality of similar cassettes (not shown), this serves as a bottom support for a catalyst bed (not shown) in a reactor for a catalytic process with one or more catalyst beds of catalyst pellets. The cassette is rectangular with four sides 05 and has a grid of crossing steel profiles to support the screen. The four side edges of the screen are supported by a frame 03. In this embodiment the screen is a woven wire mesh. The ends of the wires are welded to the frame for stiffness and support. In each corner of the rectangular frame, there is a fixing hole (not shown in this picture) which allows the frame and screen to be fixed to the cassette by means of quick release means 04. In this embodiment the quick release means are eye-nuts which can be easily and quickly unscrewed by means of a hand tool as simple as a rod and hand power. In this way, the screen can be removed for cleaning or replaced in case of damage in very short time, in this embodiment in under 5 minutes. Further, the screen including the frame of this embodiment has a weight of less than 40 kg and thus it can be removed by the power of a single man without the expensive and time-consuming need of crane assistance.

(9) FIG. 2 shows a cassette similar to the one of FIG. 1, only here shown without the screen and therefore the mentioned grid of the cassette 06 of crossing steel profiles to support the screen can be more clearly seen. To provide strength for the catalyst pellet support but enable process gas flow with as little pressure drop as possible, the steel profiles are tall and slim. Further FIG. 2 shows the cassette without the eye-nuts and hence the threaded rods for the quick release means 07 are visible. Also it is visible how the cassette comprises a base edge on the inside top along all four sides to support the frame of the screen when it is mounted.

(10) Different types of screens can be seen in FIG. 3 and FIG. 4. FIG. 3 shows a screen with flat printed pattern apertures 08. This screen may be manufactured from a single piece of metal plate with apertures that are made by for instance laser cutting, stamping or any other suitable process as known in the art. The frame may be omitted, since a supporting edge 09 can be made by bending the four edges of the metal plate. As mentioned above, each of the corners have fixing holes 10, to fix the screen to the cassette.

(11) In the embodiment of FIG. 4 the screen is made from woven wire mesh 11, which is supported by a frame 03 of steel. The ends of the wire can be fixed to the frame e.g. by welding. Each of the frame corners has a fixing hole 10 for fixing the screen to the cassette. The structure of the wire mesh permits support of the catalyst pellets with a minimum of process gas pressure loss.