KR20240031004A - Combined reformer - Google Patents

Abstract

The present invention includes two or more catalyst tubes reacting at different temperatures, and as combustion gas sequentially supplies heat to the two or more catalyst tubes, different reforming reactions occur continuously, between a plurality of catalyst tubes, and A composite reformer capable of reducing the variation in heat absorption depending on the length of each catalyst tube is provided.

Description

COMBINED REFORMER}

The present invention relates to a composite reformer, and more specifically, to a composite reformer, which includes two or more catalyst tubes reacting at different temperatures, and that different reforming reactions occur continuously as combustion gas sequentially supplies heat to the two or more catalyst tubes. It relates to a composite reformer capable of reducing the variation in heat absorption between a plurality of catalyst tubes and along the length of each catalyst tube.

A conventional steam methane reformer (SMR; Steam Methane Reforming) is a facility for reforming natural gas whose main component is methane (CH4). When gas containing high carbon hydrocarbons (CxHy) needs to be reformed, a separate device called a pre-reformer is used. There is a problem in that the structure and process are complicated because additional facilities must be added to convert it to methane and then reform it.

In addition, even when biogas needs to be reformed, the carbon dioxide contained in the biogas must be removed and then supplied to a steam methane reformer, so there is a problem that separate equipment for carbon dioxide removal is required.

Republic of Korea Patent Publication No. 2019-0112290 (published on October 4, 2019)

The present invention includes two or more catalyst tubes reacting at different temperatures, and as combustion gas sequentially supplies heat to the two or more catalyst tubes, different reforming reactions occur continuously, between a plurality of catalyst tubes, and The purpose is to provide a composite reformer that can reduce the variation in heat absorption depending on the length of each catalyst tube.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

One embodiment of the present invention for solving the above problem includes a main body; a plurality of first catalyst tubes installed in the main body and reacting at a first temperature; and a plurality of first catalyst tubes installed in the main body and reacting at a first temperature higher than the first temperature. a plurality of second catalyst tubes reacting at a second temperature; and a plurality of connection tubes respectively connecting the plurality of first catalyst tubes and the plurality of second catalyst tubes; and a combustion unit for supplying heat to the plurality of first catalyst tubes and the plurality of second catalyst tubes, wherein the combustion gas supplied from the combustion unit is disposed in the main body between the plurality of first catalyst tubes and the plurality of second catalyst tubes. A composite reformer is provided, wherein a plurality of combustion gas outlets for discharging heat after supplying heat to a plurality of second catalyst tubes are arranged at regular intervals along the circumferential direction of the main body.

Depending on the embodiment, the plurality of combustion gas outlets may be located on the side of the main body.

Depending on the embodiment, the plurality of combustion gas outlets are located on the lower surface of the main body and may further include a support part for supporting the main body.

Another embodiment of the present invention for solving the above problem is a main body; a plurality of first catalyst tubes installed in the main body and reacting at a first temperature; and a plurality of first catalyst tubes installed in the main body and higher than the first temperature. a plurality of second catalyst tubes reacting at a second temperature; and a plurality of connection tubes respectively connecting the plurality of first catalyst tubes and the plurality of second catalyst tubes; and a combustion unit for supplying heat to the plurality of first catalyst tubes and the plurality of second catalyst tubes, wherein the combustion gas supplied from the combustion unit is disposed in the main body between the plurality of first catalyst tubes and the plurality of second catalyst tubes. An exhaust chamber is formed where heat is supplied to a plurality of second catalyst tubes, and the exhaust chamber is provided with a combustion gas outlet for discharging the combustion gas.

Depending on the embodiment, the discharge chamber may be formed between a lower surface of the main body and a separation wall supported by a support part to be spaced apart from the lower surface of the main body.

Depending on the embodiment, the combustion gas is supplied to the center of the main body, the plurality of second catalyst tubes are located radially inside the main body than the plurality of first catalyst tubes, and the plurality of first catalyst tubes a first wall provided between the plurality of second catalyst tubes; and a second wall provided on a radial inner side of the plurality of second catalyst tubes, wherein the first wall may extend from the separation wall.

Depending on the embodiment, the plurality of first catalyst tubes are formed in a U shape, and each U-shaped first catalyst tube may extend along the longitudinal and circumferential directions of the main body.

Depending on the embodiment, it may further include a spiral guide plate passing through the plurality of first catalyst tubes to guide the combustion gas.

Depending on the embodiment, the plurality of first catalyst tubes may be inserted through the guide plate.

Depending on the embodiment, the guide plate may be composed of a plurality of sub-plates divided into portions passing through each first catalyst tube.

Depending on the embodiment, the combustion gas is supplied to the center of the main body, the plurality of second catalyst tubes are located radially inside the main body than the plurality of first catalyst tubes, and the plurality of first catalyst tubes a first wall provided between the plurality of second catalyst tubes; and a second wall provided on a radial inner side of the plurality of second catalyst tubes, wherein a flow hole through which combustion gas flows may be formed in the second wall.

Depending on the embodiment, a plurality of flow holes are formed along the flow direction in which combustion gas flows through the plurality of second catalyst tubes, and as the flow direction increases, the gap between flow holes adjacent to the flow direction may narrow. there is.

Depending on the embodiment, a portion of the second wall surrounding the flow hole may be provided with a first inclined portion inclined toward a flow direction in which combustion gas flows through the plurality of second catalyst tubes.

Depending on the embodiment, the first inclined portion may be formed by lancing the second wall.

According to the embodiment, a portion of the second wall surrounding the flow hole is formed to be inclined outward in the radial direction of the main body so that combustion gas flowing through the flow hole can flow toward the circumferential direction of the main body. A second inclined portion may be provided.

Depending on the embodiment, the hydrocarbon gas supplied to the plurality of first catalyst tubes includes hydrocarbons having a carbon number of 2 or more, and in the plurality of first catalyst tubes, the hydrocarbons having a carbon number of 2 or more react with steam and are reformed into methane, In the plurality of second catalyst tubes, methane may react with steam and be reformed into synthesis gas containing hydrogen and carbon monoxide.

Depending on the embodiment, the hydrocarbon gas supplied to the plurality of first catalyst tubes includes methane and carbon dioxide, and in the plurality of first catalyst tubes, methane reacts with steam and is reformed into a synthesis gas containing hydrogen and carbon monoxide. , methane may react with carbon dioxide in the plurality of second catalyst tubes and be reformed into synthesis gas containing hydrogen and carbon monoxide.

According to the present invention, two or more catalyst tubes reacting at different temperatures are included in one body, and different reforming reactions can be performed continuously as combustion gas sequentially supplies heat to the two or more catalyst tubes. For example, when pyrolysis gas and steam are supplied, hydrocarbons with a carbon number of 2 or more may react with steam and be reformed into methane, and at the same time, methane may react with steam and be reformed into synthesis gas. In this case, the structure and process are simplified because there is no need to separately install a preliminary reformer. As another example, when biogas and steam are supplied, methane may react with steam and be reformed into synthesis gas (wet reforming), and at the same time, methane may react with carbon dioxide and be reformed into synthesis gas (dry reforming). In this case, there is no need to separately remove carbon dioxide from biogas and then supply it to a reformer, so a device for removing carbon dioxide is not needed.

In addition, as a plurality of combustion gas outlets are arranged at regular intervals along the circumferential direction of the main body, or a combustion gas outlet is provided in a separate exhaust chamber formed in the main body, biasing of combustion gases can be prevented, The difference in heat absorption between primary catalyst tubes can be reduced.

Additionally, as a flow hole through which combustion gas flows is formed in the second wall, the variation in heat absorption amount according to the length of each secondary catalyst tube can be reduced.

The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a perspective view showing a complex reformer according to a first embodiment of the present invention;
Figure 2 is a perspective view showing part of the main body in Figure 1 omitted;
Figure 3 is a cross-sectional view of Figure 1;
Figure 4 is a front view showing a portion of the second wall of Figure 3;
5 to 6 are cross-sectional views showing other examples of the second wall;
7 is a plan view showing another embodiment of the second wall;
Figure 8 is a perspective view showing another embodiment of the guide plate;
Figure 9 is a perspective view showing a complex reformer according to a second embodiment of the present invention;
Figure 10 is a perspective view showing a complex reformer according to a third embodiment of the present invention;
Figure 11 is a cross-sectional view of Figure 10.

Hereinafter, preferred embodiments of the composite reformer of the present invention will be described with reference to the attached drawings.

In addition, the terms described below are terms defined in consideration of the functions in the present invention, and may vary depending on the intention or custom of the user or operator, and the examples below do not limit the scope of the present invention, but rather define the scope of the present invention. These are merely examples of the components presented in the claims.

In order to clearly explain the present invention, parts that are not relevant to the description are omitted, and identical or similar components are assigned the same reference numerals throughout the specification. Throughout the specification, when it is said that a part “includes” a certain element, this means that other elements may be further included rather than excluding other elements, unless specifically stated to the contrary.

First, let's look at the complex reformer according to the first embodiment of the present invention with reference to FIGS. 1 to 4.

The composite reformer according to the first embodiment of the present invention largely includes a main body 100, a first catalyst tube 200, a connecting tube 300, a second catalyst tube 400, a combustion section 500, and a combustion gas outlet ( 600).

The main body 100 forms the outer shape of the composite reformer and is formed in a cylindrical shape with an internal space, but is not limited thereto.

The main body 100 is equipped with two or more catalyst tubes that react at different temperatures. Specifically, a first catalyst tube 200 reacting at a first temperature T1 and a second catalyst tube 400 reacting at a second temperature T2 higher than the first temperature T1 are provided. The first temperature T1 and the second temperature T2 may be set differently depending on the reaction occurring in the first catalyst tube 200 and the second catalyst tube 400.

In this embodiment, hydrocarbon gas and steam containing hydrocarbons with a carbon number of 2 or more are supplied to the first catalyst tube 200, and in the first catalyst tube 200, hydrocarbons with a carbon number of 2 or more react with steam and are reformed into methane. , The description will be based on the case where methane reacts with steam in the second catalyst tube 400 and is reformed into synthesis gas containing hydrogen and carbon monoxide.

The first temperature T1, which is the reaction temperature of the first catalyst tube 200, may be about 350°C to 550°C, and a catalyst for reforming hydrocarbons having 2 or more carbon atoms is applied. For example, a nickel-based catalyst using MgO, Al2O3, or a combination thereof as a support may be applied to the first catalyst tube 200. Because of this, in the first catalyst tube 200, higher hydrocarbons with carbon numbers of 2 or more, such as ethane, propane, and butane, can be converted into methane, carbon monoxide, and hydrogen through reaction equations (1) and (2).

Scheme (1) ------- CnHm + nH2O → nCO + (n+m/2)H2

Reaction equation (2) ------- CO + 3H2 → CH4 + H2O

The second temperature T2, which is the reaction temperature of the second catalyst tube 400, may be about 700°C to 900°C, and a catalyst for reforming methane is applied. For example, a nickel-based catalyst may also be applied to the second catalyst tube 400. Because of this, in the second catalyst tube 400, methane can be converted into synthesis gas (syngas) containing hydrogen and carbon monoxide through reaction equation (3).

Scheme (3) ------- CH4 + H2O → CO + 3H2

Here, the wet reforming reaction of methane is described as taking place in the second catalyst tube 400, but since the wet reforming reaction of methane can occur in a wide temperature range, it may also partially take place in the first catalyst tube 200.

The first catalyst tube 200 and the second catalyst tube 400 are connected through a connecting tube 300, so that the hydrocarbon gas and steam supplied to the first catalyst tube 200 are connected from the first catalyst tube 200. It may sequentially flow through the tube 300 to the second catalyst tube 400.

Accordingly, even if the hydrocarbon gas supplied to the first catalyst tube 200 contains a large amount of hydrocarbons with a carbon number of 2 or more, the steam reforming reaction occurs by sequentially flowing through the first catalyst tube 200 and the second catalyst tube 400. It can be reformed into synthetic gas through . That is, high-grade hydrocarbons with a carbon number of 2 or more can be converted into methane in the first catalyst tube 200, and the methane converted in the first catalyst tube 200 flows into the second catalyst tube 400 and is converted into synthesis gas. It can be. In particular, the hydrocarbon gas supplied to the first catalyst tube 200 may be a pyrolysis gas generated through pyrolysis of waste. For example, it may be pyrolysis gas generated by pyrolysis of waste plastic, and it contains a large amount of hydrocarbons with a carbon number of 2 or more.

A combustion unit 500 is installed at the upper center of the main body 100 to supply heat to the first catalyst tube 200 and the second catalyst tube 400, and hydrocarbon gas is burned in the combustion unit 500. Combustion gas is produced. The generated combustion gas is supplied to the center of the main body 100.

Since the second catalyst tube 400 reacts at a higher temperature than the first catalyst tube 200, the combustion gas supplied from the combustion unit 500 supplies heat to the second catalyst tube 400 and then flows to the first catalyst tube 400. It is effective to supply heat to (200). To this end, the second catalyst tube 400 is located radially inside the main body 100 than the first catalyst tube 200. In this embodiment, the first catalyst tube 200 and the second catalyst tube 400 are composed of a plurality, and the plurality of first catalyst tubes 200 and the plurality of second catalyst tubes 400 are connected to the main body 100. They are arranged spaced apart along the circumferential direction. In addition, the plurality of first catalyst tubes 200 and the plurality of second catalyst tubes 400 each extend vertically along the longitudinal direction of the main body 100.

However, it is not limited to this, and according to the embodiment, the first catalyst tube 200 is configured so that the combustion gas supplies heat to the first catalyst tube 200 and then supplies heat to the second catalyst tube 400. 2 It may be located radially inside the main body 100 rather than the catalyst tube 400.

Specifically, as shown in FIG. 2, in this embodiment, eight second catalyst tubes 400 are arranged at regular intervals along the circumferential direction of the main body 100. Similarly, eight first catalyst tubes 200 are arranged to be spaced apart along the circumferential direction of the main body 100, and are arranged to surround the second catalyst tubes 400. There are also eight connecting tubes 300 that connect one first catalyst tube 200 and one second catalyst tube 400. However, the number of catalyst tubes and connection tubes is not limited to this and may be formed in various ways depending on the size of the reformer, etc.

In this embodiment, the plurality of first catalyst tubes 200 are formed in a U shape, and each U-shaped first catalyst tube 200 extends along the longitudinal and circumferential directions of the main body 100. As the first catalyst tube 200 is formed in a U shape, the catalyst reaction time may be increased. Alternatively, the U-shaped first catalyst tube 200 may be provided with a temperature raising section in which the temperature of the hydrocarbon gas is raised before catalytic reforming and a catalytic reforming section in which the hydrocarbon gas is catalytically reformed.

Additionally, the plurality of second catalyst tubes 400 are made of bayonet tubes. That is, each of the second catalyst tubes 400 consists of an outer tube 420 and an inner tube 440 disposed inside the outer tube 420. The inner tube 440 is fixed to the outer tube 420 and extends along the longitudinal direction inside the outer tube 420, but does not contact the end of the outer tube 420 and forms a certain space therebetween. Because of this, the outer tube 420 and the inner tube 440 can be communicated with each other, and the gas flowing between the outer tube 420 and the inner tube 440 through the connecting tube 300 is connected to the inner tube 440. It can flow internally. In this embodiment, the connecting tube 300 is connected to the outer tube 420, but the connection tube 300 is not limited thereto and may be connected to the inner tube 440.

Ultimately, the hydrocarbon gas and steam flowing into the first catalyst tube 200 undergo primary reforming while passing through the first catalyst tube 200, and then travel to the outer part of the second catalyst tube 400 through the connection tube 300. It flows between the tube 420 and the inner tube 440 and undergoes secondary reforming. Thereafter, the synthetic gas may flow into the inner tube 440 and then be discharged through a synthetic gas outlet (not shown).

Inside the main body 100, there is a first wall 120 to guide the flow of combustion gas discharged from the combustion unit 500 and effectively supply heat to the first catalyst tube 200 and the second catalyst tube 400. and a second wall 140. The first wall 120 is provided between the first catalyst tube 200 and the second catalyst tube 400, and extends vertically upward from the bottom of the main body 100 in the drawing. Additionally, the second wall 140 is provided on the radial inner side of the second catalyst tube 400 and extends vertically downward from the upper side of the main body 100 in the drawing. Accordingly, the combustion gas supplied from the combustion unit 500 flows zigzagly along the longitudinal direction of the first catalyst tube 200 and the second catalyst tube 400, thereby forming the first catalyst tube 200 and the second catalyst tube 400. Sufficient heat can be supplied to (400), and a temperature gradient according to the reaction temperature can be applied. To improve heat transfer efficiency, fins may be placed on the first catalyst tube 200 and/or the second catalyst tube 400.

Specifically, as shown in FIG. 3, the combustion gas supplied from the combustion unit 500 flows downward, passes to the second catalyst tube 400 through the space below the second wall 140, and then flows upward. Heat is supplied to the second catalyst tube 400. Thereafter, the combustion gas whose temperature has been partially lowered passes through the space above the first wall 120 toward the first catalyst tube 200 and then flows downward again to supply heat to the first catalyst tube 200. After heat is supplied to the first catalyst tube 200 and the second catalyst tube 400, combustion gas is discharged to the outside through the combustion gas outlet 600 provided in the main body 100.

At this time, if only one combustion gas outlet is provided on one side of the lower part of the main body 100, the flow of combustion gas is biased toward the outlet, and a difference in heat absorption may occur between the plurality of first catalyst tubes 200. As a result, if some of the plurality of first catalyst tubes 200 have low heat absorption and are not raised to a temperature suitable for the catalytic reforming reaction, a problem occurs in which hydrogen production efficiency is reduced.

Accordingly, in this embodiment, the combustion gas supplied from the combustion unit 500 supplies heat to the plurality of first catalyst tubes 200 and the plurality of second catalyst tubes 400, and then is used as a plurality of combustion gases to be discharged. Discharge ports 600 are arranged at regular intervals along the circumferential direction of the main body 100. In this embodiment, four combustion gas outlets 600 are arranged at 90° intervals. Additionally, a plurality of combustion gas outlets 600 are located on the lower side of the main body 100. As a result, in contrast to the case where only one combustion gas outlet is provided on one side of the lower part of the main body 100, bias in combustion gas does not occur, and the heat absorption variation between the plurality of primary catalyst tubes 200 can be reduced. .

Furthermore, depending on the embodiment, as shown in FIG. 2, a spiral guide plate 700 passing through the plurality of first catalyst tubes 200 may be further included to guide combustion gas.

The guide plate 700 is formed as a spiral plate surrounding the first wall 120 to guide combustion gas flowing between the first wall 120 and the main body 100, and includes a plurality of first catalyst tubes 200. ) is inserted through the guide plate 700. To this end, the guide plate 700 is provided with a through hole for the plurality of first catalyst tubes 200 to pass through, and the first catalyst tube 200 can be inserted into the through hole and then fixed through welding.

Accordingly, the combustion gas flows along the spiral guide plate 700 and passes through all the first catalyst tubes 200, thereby further reducing the heat absorption difference between the plurality of first catalyst tubes 200, and the combustion gas 1 As the speed of passage through the catalyst tube 200 increases and the external heat transfer coefficient increases, the heat absorption amount of the first catalyst tube increases. Additionally, gas temperature or flow unevenness at the inlet of the first catalyst tube 200 can be resolved.

However, in this embodiment, since a plurality of first catalyst tubes 200 are coupled to one guide plate 700, there is a disadvantage in that individual A/S of the first catalyst tube is difficult.

To solve this, in another embodiment shown in FIG. 8, the guide plate 700 may be composed of a plurality of sub plates 700a divided for each portion passing through each U-shaped first catalyst tube 200. . That is, a sub plate 700a is installed in each U-shaped first catalyst tube 200, and the sub plates 700a form a spiral plate that entirely surrounds the first wall 120. At this time, it is desirable to minimize the distance between adjacent subplates 700a.

Depending on the embodiment, as shown in FIGS. 3 and 4, a flow hole 800 through which combustion gas flows may be formed in the second wall 140. A plurality of flow holes 800 are formed along the longitudinal and circumferential directions of the second wall 140. In particular, as shown in FIG. 4, it is preferable that the plurality of flow holes 800 are formed in a zigzag pattern. The longitudinal direction of the second wall 140 corresponds to the flow direction d in which combustion gas flows through the plurality of second catalyst tubes 400. The shape of the flow hole 800 is shown as being rectangular, but it is not limited to this and can be formed in various shapes such as circular or oval.

In addition to the combustion gas passing through the space under the second wall 140 toward the second catalyst tube 400, the combustion gas may pass toward the second catalyst tube 400 through the plurality of flow holes 800. . As a result, heat absorption can be prevented from being concentrated only on the lower end of the second catalyst tube 400 as shown in the drawing, and thus the variation in heat absorption amount according to the length of each second catalyst tube 400 can be reduced. In addition, after the combustion gas passes through the flow hole 800, it may reach the second catalyst tube 400, causing an increase in heat flux due to impingement.

3 and 4 show a plurality of flow holes 800 having the same spacing in the flow direction (d). However, in FIG. 5, a plurality of flow holes 800 have a structure having different spacings in the flow direction (d). It is being shown. At this time, the distance between flow holes 800 adjacent to the flow direction becomes narrower as one moves upward in the flow direction d, that is, upward in the drawing. This is to increase the amount of heat absorption by placing more flow holes 800 in a section of the second catalyst tube 400 with low heat absorption.

In addition, in FIG. 6, a first slope is formed on a portion of the second wall 140 surrounding the flow hole 800 to be inclined toward the flow direction (d) in which combustion gas flows through the plurality of second catalyst tubes 400. A structure in which the unit 142 is provided is shown. Specifically, the first inclined portion 142 is formed to be inclined upward while being fixed to the lower side of the second wall 140 surrounding the flow hole 800 in the drawing. As a result, the combustion gas passing through the flow hole 800 can flow toward the flow direction (d), and after crossing toward the second catalyst tube 400 through the space below the second wall 140, the combustion gas passes through the flow direction (d). It is possible to flow together without interfering with the flow of combustion gases flowing to d). The first inclined portion 142 may be formed in various shapes, such as a rectangular surface or a triangular surface forming a tetrahedron. At this time, the first inclined portion 142 may be formed by lancing the second wall 140. That is, after cutting a portion of the position where the flow hole 800 is to be formed in the second wall 140 (for example, a portion corresponding to three of the four sides of the rectangle), the cut portion is bent to form the flow hole. Together with 800, the first inclined portion 142 can be formed.

Next, in FIG. 7, a portion of the second wall 140 surrounding the flow hole 800 is provided so that the combustion gas flowing through the flow hole 800 can flow toward the circumferential direction of the main body 100. A structure is shown in which a second inclined portion 144 is formed to be inclined toward the radial outer side of (100). Figure 7, unlike Figures 5 and 6, is shown in a top view. Specifically, the second inclined portion 144 is fixed to the left side of the second wall 140 surrounding the flow hole 800 in the drawing and is formed to be inclined radially outward, that is, toward the second catalyst tube 400. It is becoming. As a result, the combustion gas passing through the flow hole 800 can flow toward the circumferential direction of the main body 100, and flows after passing toward the second catalyst tube 400 through the space under the second wall 140. It can combine with combustion gas flowing in direction (d) and flow diagonally. In this way, as the combustion gas flows diagonally through the plurality of second catalyst tubes 400, the moving distance and speed of the combustion gas are increased to increase the amount of heat absorption of the second catalyst tube 400, and the plurality of second catalyst tubes 400 ) can also reduce the variation in heat absorption. The second inclined portion 144 may also be formed by lancing the second wall 140.

The complex reformer according to the first embodiment of the present invention includes a plurality of combustion gas outlets 600, a guide plate 700, and a flow hole 800, but only one of these is included and the rest will be omitted. Of course it is possible.

Depending on the embodiment, hydrocarbon gas (eg, biogas) containing methane and carbon dioxide and steam may be supplied to the first catalyst tube 200. Below, we will look at the reforming reaction that occurs in the first catalyst tube 200 and the second catalyst tube 400 when biogas and steam are supplied to the first catalyst tube 200. The structure of the composite reformer except for the reforming reaction is the same as described above.

When biogas and steam are supplied to the first catalyst tube 200, methane reacts with steam in the first catalyst tube 200 through reaction equation (3) and is reformed into synthesis gas containing hydrogen and carbon monoxide (wet reforming), in the second catalyst tube 400, methane reacts with carbon dioxide through reaction equation (4) and can be reformed into synthesis gas containing hydrogen and carbon monoxide (dry reforming).

Scheme (3) ------- CH4 + H2O → CO + 3H2

Reaction formula (4) ------- CH4 + CO2 → 2CO + 2H2

In this case, the first temperature T1, which is the reaction temperature of the first catalyst tube 200, may be about 450°C to 650°C, and a catalyst for wet reforming methane may be applied. The second temperature T2, which is the reaction temperature of the second catalyst tube 400, may be about 650°C to 850°C, and a catalyst for dry reforming methane may be applied.

Here, the wet reforming reaction of methane is described as taking place in the first catalyst tube 200, but since the wet reforming reaction of methane can occur in a wide temperature range, it may also partially take place in the second catalyst tube 400.

In this way, hydrocarbon gas (here, biogas containing methane and carbon dioxide) and steam sequentially flow through the first catalyst tube 200 and the second catalyst tube 400 to produce synthetic gas through wet reforming reaction and dry reforming reaction. can be reformed. In this case, there is no need to separately remove carbon dioxide from biogas and then supply it to a reformer, so a device for removing carbon dioxide is not needed.

Next, let's look at the complex reformer according to the second embodiment of the present invention with reference to FIG. 9.

The composite reformer according to the second embodiment has the same configuration as the composite reformer according to the first embodiment, but a plurality of combustion gas outlets 600 are located on the lower surface of the main body 100, and a plurality of combustion gas outlets 600 are located below the main body 100. The difference is that a support portion 900 for supporting the main body 100 is further included to form a space for the combustion gas outlet 600.

The plurality of combustion gas outlets 600 are similarly arranged to be spaced apart at regular intervals along the circumferential direction of the main body 100. In addition, the support portion 900 supports the main body 100 and forms a space for placing a plurality of combustion gas outlets 600 below the main body 100.

Lastly, let's look at the complex reformer according to the third embodiment of the present invention with reference to FIGS. 10 and 11.

Like the first embodiment, the composite reformer according to the third embodiment of the present invention includes a main body 100, a first catalyst tube 200, a connecting tube 300, a second catalyst tube 400, and a combustion unit 500. Includes. However, there is a difference in that the combustion gas outlet 600 is not formed, a separate exhaust chamber 3180 is formed in the main body 100, and the combustion gas outlet 3600 is provided in the exhaust chamber 3180.

Specifically, an exhaust chamber 3180 is formed in the main body 100 where combustion gas collects after supplying heat to the plurality of first catalyst tubes 200 and the plurality of second catalyst tubes 400. In this embodiment, the discharge chamber 3180 is formed between the lower surface of the main body 100 and the separation wall 3160 supported by the support portion 3170 to be spaced apart from it. The separation wall 3160 is preferably formed in a circular shape corresponding to the shape of the lower surface of the main body 100 and has a smaller size than the lower surface of the main body 100. In addition, the separation wall 3160 is preferably formed closer to the lower surface of the main body 100 than to the lower end of the first catalyst tube 200, that is, to the U-turn section of the first catalyst tube 200. The support portion 3170 may be formed in various shapes, such as a cylindrical shape or a plate shape.

In this case, when the first wall 120 discussed above extends from the lower surface of the main body 100 as in the first embodiment, it blocks the discharge chamber 3180, so the first wall 120 is a separation wall 3160. It extends vertically from above.

The combustion gas outlet 3600 is preferably installed at the center of the lower surface of the main body 100 and communicates with the exhaust chamber 3180. Accordingly, after supplying heat to the plurality of first catalyst tubes 200, combustion gas flowing downward may be collected in the exhaust chamber 3180 and then discharged through the combustion gas outlet 3600. As a result, compared to the case where only one combustion gas outlet is provided on one side of the lower part of the main body 100, bias in combustion gas does not occur, and the heat absorption variation between the plurality of primary catalyst tubes 200 can be reduced. .

The present invention is not limited to the specific embodiments and descriptions described above, and various modifications can be made by anyone skilled in the art without departing from the gist of the invention as claimed in the claims. and such modifications fall within the protection scope of the present invention.

100: main body 120: first wall
140: second wall 142: first slope
144: second inclined portion 200: first catalyst tube
300: Connecting tube 400: Second catalyst tube
420: Outer tube 440: Inner tube
500: Combustion unit 600: Combustion gas outlet
700: Guide plate 700a: Sub plate
800: Flow hole 900: Support part
3160: separating wall 3170: support
3180: Exhaust chamber 3600: Combustion gas outlet

Claims (17)

main body;
a plurality of first catalyst tubes installed in the main body and reacting at a first temperature;
a plurality of second catalyst tubes installed in the main body and reacting at a second temperature higher than the first temperature;
a plurality of connection tubes respectively connecting the plurality of first catalyst tubes and the plurality of second catalyst tubes; and
It includes a combustion unit for supplying heat to the plurality of first catalyst tubes and the plurality of second catalyst tubes,
The main body has a plurality of combustion gas outlets at regular intervals along the circumferential direction of the main body for the combustion gas supplied from the combustion unit to be discharged after supplying heat to the plurality of first catalyst tubes and the plurality of second catalyst tubes. A complex reformer, characterized in that it is arranged spaced apart.
According to paragraph 1,
A composite reformer, wherein the plurality of combustion gas outlets are located on a side of the main body.
According to paragraph 1,
The plurality of combustion gas outlets are located on the lower surface of the main body,
A composite reformer further comprising a support part for supporting the main body.
main body;
a plurality of first catalyst tubes installed in the main body and reacting at a first temperature;
a plurality of second catalyst tubes installed in the main body and reacting at a second temperature higher than the first temperature;
a plurality of connection tubes respectively connecting the plurality of first catalyst tubes and the plurality of second catalyst tubes; and
It includes a combustion unit for supplying heat to the plurality of first catalyst tubes and the plurality of second catalyst tubes,
An exhaust chamber is formed in the main body where combustion gas supplied from the combustion unit collects after supplying heat to the plurality of first catalyst tubes and the plurality of second catalyst tubes,
A composite reformer, characterized in that the discharge chamber is provided with a combustion gas outlet for discharging the combustion gas.
According to paragraph 4,
The discharge chamber is a composite reformer, characterized in that it is formed between a lower surface of the main body and a separation wall supported by a support part to be spaced apart from the discharge chamber.
According to clause 5,
The combustion gas is supplied to the center of the main body, and the plurality of second catalyst tubes are located radially inside the main body than the plurality of first catalyst tubes,
a first wall provided between the plurality of first catalyst tubes and the plurality of second catalyst tubes; and a second wall provided on the radial inner side of the plurality of second catalyst tubes,
A composite reformer, wherein the first wall extends from the separating wall.
According to claim 1 or 4,
A composite reformer, wherein the plurality of first catalyst tubes are formed in a U shape, and each U-shaped first catalyst tube extends along the longitudinal and circumferential directions of the main body.
According to claim 1 or 4,
A composite reformer further comprising a spiral guide plate passing through the plurality of first catalyst tubes to guide the combustion gas.
According to clause 8,
A composite reformer, characterized in that the plurality of first catalyst tubes are inserted through the guide plate.
According to clause 8,
The guide plate is a composite reformer, characterized in that it is composed of a plurality of sub plates divided for each part passing through the first catalyst tube.
According to claim 1 or 4,
The combustion gas is supplied to the center of the main body, and the plurality of second catalyst tubes are located radially inside the main body than the plurality of first catalyst tubes,
a first wall provided between the plurality of first catalyst tubes and the plurality of second catalyst tubes; and a second wall provided on the radial inner side of the plurality of second catalyst tubes,
A composite reformer, characterized in that a flow hole through which combustion gas flows is formed in the second wall.
According to clause 11,
A plurality of flow holes are formed along the flow direction in which combustion gas flows through the plurality of second catalyst tubes, and the gap between flow holes adjacent to the flow direction becomes narrower as the combustion gas flows through the plurality of second catalyst tubes. Reformer.
According to clause 11,
A composite reformer, wherein a portion of the second wall surrounding the flow hole is provided with a first inclined portion inclined toward a flow direction in which combustion gas flows through the plurality of second catalyst tubes.
According to clause 13,
A composite reformer, wherein the first inclined portion is formed by lancing the second wall.
According to clause 11,
A portion of the second wall surrounding the flow hole is provided with a second inclined portion formed to be inclined toward an outer radial direction of the main body so that combustion gas flowing through the flow hole can flow toward the circumferential direction of the main body. A complex reformer, characterized in that.
According to paragraph 1,
The hydrocarbon gas supplied to the plurality of first catalyst tubes contains hydrocarbons having a carbon number of 2 or more,
In the plurality of first catalyst tubes, hydrocarbons having a carbon number of 2 or more react with steam and are reformed into methane, and in the plurality of second catalyst tubes, methane reacts with steam and are reformed into synthesis gas containing hydrogen and carbon monoxide. A composite reformer.
According to paragraph 1,
The hydrocarbon gas supplied to the plurality of first catalyst tubes includes methane and carbon dioxide,
In the plurality of first catalyst tubes, methane reacts with steam and is reformed into a synthesis gas containing hydrogen and carbon monoxide, and in the plurality of second catalyst tubes, methane reacts with carbon dioxide and is reformed into a synthesis gas containing hydrogen and carbon monoxide. A complex reformer, characterized in that.

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