REACTOR AND PROCESS FOR PRODUCING A PRODUCT GAS BY GASIFICATION OF A HYDROCARBON-CONTAINING FUEL

Abstract

The present invention relates to a reactor and a process for producing a product gas by gasification of a hydrocarbon-containing fuel. The reactor has a reaction space and a cooling space and an intermediate floor which spatially separates the reaction space from the cooling space. A gas duct for ducting the product gas to be cooled from the reaction space into the cooling space extends through the intermediate floor, including a shaped body which at least partially extends over a free cross sectional area of the cooling space and effects partial blocking of the cross sectional area of the cooling space is arranged in the cooling space of the reactor, wherein the shaped body is arranged such that after flowing around the shaped body at least a portion of the cooled product gas subsequently exits the reactor via the cool gas outlet of the cooling space.

Claims

1. A reactor for producing a product gas by gasification of a hydrocarbon-containing fuel, comprising a reaction space comprising an apparatus configured to be an inlet of a fuel and an oxidant for partial oxidation of the fuel with the oxidant thereby producing a hot product gas; a cooling space configured for cooling the hot product gas by direct heat exchange with a cooling medium; a cooling medium inlet configured to supply of fresh cooling medium to the cooling space; a cool gas outlet arranged at the side of the cooling space configured for withdrawing the product gas cooled in the cooling space; an intermediate floor which spatially separates the reaction space and the cooling space; a gas duct arranged in the intermediate floor and extending through the intermediate floor configured for ducting the product gas to be cooled from the reaction space to the cooling space; a cooling medium outlet configured for withdrawing excess cooling medium from the cooling space; and a shaped body arranged in the cooling space which partially extends over a free cross sectional area of the cooling space and effects partial blocking of the cross sectional area of the cooling space, wherein the shaped body is arranged such that after flowing around the shaped body at least a portion of the cooled product gas subsequently exits the reactor via the cool gas outlet of the cooling space.

2. The reactor according to claim 1, wherein the shaped body is arranged such that after ducting of the product gas to be cooled from the reaction space to the cooling space and flow around the shaped body in the cooling space at least a portion of the cooled product gas undergoes flow along the intermediate floor of the reactor and the cooled product gas subsequently exits the reactor via the cool gas outlet.

3. The reactor according to claim 1, wherein the shaped body is in the shape of a disc.

4. The reactor according to claim 3, wherein the disc is in the shape of a segment of a circle.

5. The reactor according to claim 3, wherein the disc-shaped shaped body has a hole or a recess and the hole or the recess is arranged in the region of the gas duct of the reactor so that the hole surrounds the gas duct or the recess partially surrounds the gas duct.

6. The reactor according to claim 1, wherein the shaped body at least partially extending over a free cross sectional area of the cooling space is arranged on a side of the cooling space of the reactor facing the cool gas outlet.

7. The reactor according to claim 1, wherein the shaped body is arranged horizontally or substantially horizontally within the cooling space having regard to the plane of its main extension, preferably arranged within the cooling space at an angle of 0° to 30° to a horizontal having regard to the plane of its main extension.

8. The reactor according to claim 1, wherein the shaped body extends over the cross sectional area of the cooling space such that having regard to a projection of a plane arranged within the cooling space and below the gas duct a partial blockage of 20% to 90% of the free cross sectional area of this plane is affected.

9. The reactor according to claim 1, wherein the shaped body comprises one or a plurality of passage openings.

10. The reactor according to claim 9, wherein the passage openings of the shaped body define an open porosity of the shaped body and the open porosity is 5% to 95%.

11. The reactor according to claim 10, wherein the passage openings of the shaped body define an open porosity of the shaped body and the open porosity is 30% to 70%.

12. The reactor according to claim 10, wherein the passage openings of the shaped body define an open porosity of the shaped body and the open porosity is 70% to 90%.

13. The reactor according to claim 9, wherein the shape of the passage openings of the shaped body is selected from at least one element from the group comprising circular, cuboid, rectangular, rod-shaped or rhombic.

14. The reactor according to claim 1, wherein the cool gas outlet is arranged above the shaped body.

15. The reactor according to claim 1, wherein the gas duct has a first end and a second end, wherein the first end is adjacent to the reaction space and the second end is adjacent to the cooling space and wherein the shaped body is arranged adjacent to the second end of the gas duct or is joined to the second end of the gas duct.

16. The reactor according to claim 1, wherein one or a plurality of apparatuses for treating the product gas to be cooled with cooling medium are arranged on an inner surface or at one end of the gas duct.

17. The reactor according to claim 1, wherein the intermediate floor of the reactor and/or the shaped body are provided with a flow baffle or a plurality of flow baffles.

18. A process for producing a synthesis gas, by gasification of a hydrocarbon-containing fuel in a reactor, comprising: a) producing a hot product gas by partial oxidation of the hydrocarbon-containing fuel with an oxidant in a reaction space of the reactor; b) passing the hot product gas into a cooling space of the reactor for cooling the hot product gas by direct heat exchange with a cooling medium; c) flowing at least a portion of the product gas to be cooled around a shaped body arranged in the cooling space; d) withdrawing the cooled product gas from the cooling space after at least a portion of the cooled product gas has flowed around the shaped body according to c).

19. The process according to claim 18, wherein the cooled product gas is passed along an intermediate floor of the reactor before it is withdrawn from the cooling space, wherein the intermediate floor spatially separates the reaction space and the cooling space from one another.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0084] The invention is hereinbelow particularized by drawings and working examples, wherein the drawings and the working examples are not intended to limit the invention in any way. The drawings are not to scale unless otherwise stated.

In the figures

[0085] FIG. 1 shows a schematic representation of a reactor according to the invention,

[0086] FIG. 2(a) shows an embodiment of an inventive shaped body in each case without gas passage openings,

[0087] FIG. 2(b) shows an embodiment of an inventive shaped body in each case with gas passage openings,

[0088] FIG. 3(a) shows a pictorial representation of the distribution of the heat transfer coefficients over the intermediate floor of the reactor according to a comparative example,

[0089] FIG. 3(b) shows a pictorial representation of the distribution of the heat transfer coefficients over the intermediate floor of the reactor according to an inventive example,

[0090] FIG. 3(c) shows a pictorial representation of the distribution of the heat transfer coefficients over the intermediate floor of the reactor according to an inventive example, and

[0091] FIG. 4 shows a graphical representation of the distribution of the heat transfer coefficients over the intermediate floor of the reactor according to a comparative example and two inventive examples.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0092] FIG. 1 shows a highly simplified, schematic representation of an example of a reactor 1 according to the invention. Reactor 1 has an upper reaction space 2 and a lower cooling space 6. The reaction space 2 and the cooling space 6 are spatially separated from one another by a load-bearing intermediate floor 20. A gas duct 12 arranged in the intermediate floor 20 which extends through the intermediate floor 20 makes a fluid connection between the reaction space 2 and the cooling space 6. The gas duct 12 has a first end 12a which is adjacent to the reaction space 2 and a second end 12b which is adjacent to the cooling space 6.

[0093] The reaction space 2 has a burner 4 and an inlet 3 for hydrocarbon-containing fuel and oxidant. A mixture 5 of hydrocarbon-containing fuel and oxidant is introduced from an upper side of the reactor via the inlet 3 into the reaction space 2 and using the burner 4 to form a flame partially converted into a hot product gas 8 which subsequently exits the reaction space 2 by flowing through the gas duct 12 and enters the cooling space 6.

[0094] The fuel is for example liquid fractions from crude oil processing, in particular high-boiling residues from crude oil processing. The oxidant is air for example. Due to the high temperatures of often over 1000° C. prevailing in the reaction space 2 the interior of said space is provided with a refractory lining (not shown). The reactor shell of the reaction space 2 is made of a heat resistant alloy. The hot product gas 8 formed is carbon monoxide-rich and hydrogen-rich synthesis gas.

[0095] The cooling space 6 forming the lower portion of the reactor 1 has a cooling media inlet 9, by means of which the cooling space 6 is supplied with fresh cooling medium 7. The cooling medium 7 supplied to the cooling space 6 is distributed as fine mist via nozzles (not shown) arranged within the gas duct 12 and thus cools the hot product gas 8 flowing through the gas duct by direct heat transfer from the hot product gas to the cooling medium 7. A portion of the evaporated cooling medium exits the reactor 1 together with the cooled product gas via a cool gas outlet 10 arranged at the side of the cooling space 6 of the reactor 1. Excess cooling medium collects in the sump, comprising a cooling medium reservoir 19, of the cooling space 6 and is continuously withdrawn from the cooling space 6 of the reactor 1 via the cooling media outlet 14 as excess cooling medium 15.

[0096] Arranged in the cooling space 6 is a shaped body 13 partially extending over the free cross sectional area of the cooling space 6. The shaped body 13 is in the form of a segment of a circle, the inside of which has a recess which is adjacent to the second end 12b of the gas duct 12 and is therefore in contact with the gas duct 12. Depending on the embodiment and arrangement the recess may completely or partially surround the gas duct 12. The shaped body 13 is arranged substantially between the gas duct 12 and an inner surface of the wall of the cooling space 6 of the reactor on a side facing the cool gas outlet 10. Depending on the type of securing the shaped body 13 may be joined to the second end 12b of the gas duct 12 in an interlocking, force-fit or integrally bonded manner and/or secured to the wall of the cooling space 6.

[0097] The cool gas outlet 10 is arranged above the shaped body 13 and below the intermediate floor 20. This arrangement ensures that after passing through the gas duct 12 the cooled product gas 11a does not primarily flow directly to the cool gas outlet 10, which would result in only a small extent of flow over the region below the intermediate floor 20. On the contrary the arrangement of the shaped body 13 with partial blocking of the free cross sectional area of the cooling space 6 has the result that in FIG. 1 the cooled product gas at least partially flows via the left-hand side to the cool gas outlet 10, thus achieving more uniform and better cooling of the intermediate floor 20, in particular in the region facing away from cool gas outlet 10.

[0098] If no inventive shaped body 13 is arranged within the cooling space as in the reactors known from the prior art this has the result that the cooled product gas 11a hardly flows through the region below the intermediate floor 20 since it very largely flows directly from the second end 12b of the gas duct 12 to the cool gas outlet 10 at a significant distance from the intermediate floor 20. Gas resting in the region below the intermediate floor 20 has only a small cooling effect on the intermediate floor 20. This has the result that the intermediate floor 20 is more or less effectively cooled only locally and exclusively in the region adjacent to the cool gas outlet 10.

[0099] The inventive shaped body 13 ensures that the entirety or at least a large part of the flow of the cooled product gas 11a is diverted such that the cooled product gas 11a flows along below the intermediate floor 20 to a greater extent. This has the result that the cooling effect on the intermediate floor 20 is increased and uniformized. As a result the risk of overheating of the intermediate floor 20 and the risk of material failure due to excessive thermal stresses including in the case of failure of the high temperature resistant lining of the intermediate floor (not shown) can be markedly reduced or entirely avoided.

[0100] A shaped body 13 according to FIG. 1 further comprises a plurality of passage openings for product gas and quench water. The passage openings on the one hand bring about improved drainage of excess cooling medium in the direction of the reactor sump but can also achieve an improvement in the flow ratios in the cooling space 6.

[0101] Two examples of the shaped body 13 are shown in plain view in a simplified schematic form in FIG. 2, wherein shaped body 13a shows a shaped body 13 without passage openings and shaped body 13b shows a shaped body 13 with passage openings.

[0102] The shaped body 13a has the basic shape of a disc and in particular the shape of a segment of a circle. The shaped body 13a is composed of a total of six shaped body segments 16a, for example heat resistant metal sheets. The circle segment-shaped shaped body 13a further comprises a recess 18a which would at least partially surround the gas duct 12 according to FIG. 1. In the case of horizontal arrangement within the cooling space 6 the shaped body 13a as shown in FIG. 1 would block about 75% of the free cross sectional area of the cooling space.

[0103] The shaped body 13b has the basic shape of a disc and in particular the shape of a segment of a circle. The shaped body 13b is composed of a total of four shaped body segments 16b, for example heat resistant metal sheets. Each segment comprises twenty-eight circular passage openings 17 (holes), wherein the number of passage openings or holes may in practice be far higher. The circle segment-shaped shaped body 13b further comprises a recess 18b which would at least partially surround the gas duct 12 according to FIG. 1. In the case of horizontal arrangement within the cooling space 6 the shaped body 13b as shown in FIG. 1 would block about 50%, minus the area of the passage openings, of the free cross sectional area of the cooling space.

[0104] The configuration of the shaped body 13 is in no way limited to the examples of FIG. 2 but rather is in terms of its geometry freely choosable in principle and limited only by its introduction into the vessel of cooling space 6. Securing and positioning of the shaped body may be achieved using for example holders in the cooling space 6 in the form of clamps, brackets or rods for hanging. The geometric shape of the gas passage openings 17 of shaped body 13 is likewise freely choosable in principle and is accordingly adapted by those skilled in the art to the flow conditions in the reactor as well as the availability and accessibility for each individual case.

[0105] FIG. 3 shows the results of a CFD simulation for a comparative example (a) without a shaped body and two inventive examples (b) and (c) with a shaped body 13 in a pictorial representation. In inventive example (b) a CFD simulation was performed for a shaped body configured as a porous plate of semicircular geometry. The shaped body has an open porosity of 50% and blocks about 50% of the free cross sectional area of the cooling space 6 of reactor 1. The shaped body 13 extends in the horizontal direction to the height of the gas duct 12 and is arranged between the gas duct 12 and an inner surface of the wall of the cooling space 6 and below the cool gas outlet 10. Example (c) is subject to the same boundary conditions as example (b) but the shaped body has an open porosity of 80%.

[0106] The figure shows the distribution of heat transfer over the intermediate floor 20 using the heat transfer coefficient in watts per square meter (W/m.sup.2). What is desired is always the highest and most uniform possible heat transfer to achieve optimal cooling of and a minimum of thermal stresses in the intermediate floor 20. The left-hand side of each sub-figure shows the side facing away from the cool gas outlet 10 and the right-hand side shows the side facing the cool gas outlet 10 or adjacent thereto. The darker the color of the shading, the poorer the heat transfer, and the lighter the color, the better.

[0107] Comparative example (a) shows, in particular on the left-hand side facing away from the cool gas outlet, a large surface area region having a very low heat transfer coefficient (shown in black). Furthermore only a very small, almost point-like region in the immediate vicinity of the cool gas outlet 10 exhibits a very good heat transfer coefficient (white region). The intermediate floor is thus poorly and nonuniformly cooled according to comparative example (a). Examples (b) and (c) show a significant improvement in the form of substantially larger regions (white) have a high heat transfer coefficients and substantially smaller regions (black) having low heat transfer coefficients. The installation of the shaped body 13 thus clearly deflects the flow of the cooled product gas 11a in the direction of the surface of the intermediate floor 20 to a greater extent. Flow over the intermediate floor 20 is especially also achieved in the region of the side facing away from the cool gas outlet 10.

[0108] The graphical representation of the same simulation of FIG. 3 further elucidates that especially for example (b) (porosity 50%) better heat transfer compared to comparative example (a) is achieved over the majority of the surface area on the side facing away from the cool gas outlet 10. In example (c) (porosity 80%) improved cooling compared to comparative example (a) is achieved on both sides.

[0109] It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. Thus, the present invention is not intended to be limited to the specific embodiments in the examples given above.

LIST OF REFERENCE NUMERALS

[0110] 1 Reactor [0111] 2 Reaction space [0112] 3 Inlet for fuel and oxidant [0113] 4 Burner with flame [0114] 5 Mixture of fuel and oxidant [0115] 6 Cooling space [0116] 7 Fresh cooling medium [0117] 8 Hot product gas [0118] 9 Cooling media inlet [0119] 10 Cool gas outlet [0120] 11a, 11b Cooled product gas [0121] 12 Gas duct [0122] 12a First end of gas duct [0123] 12b Second end of gas duct [0124] 13 Shaped body [0125] 13a Shaped body without passage openings [0126] 13b Shaped body with passage openings [0127] 14 Cooling media outlet [0128] 15 Excess cooling medium [0129] 16a, 16b Shaped body segment [0130] 17 Passage opening [0131] 18a, 18b Recess [0132] 19 Sump with cooling medium reservoir [0133] 20 Intermediate floor