KR100905422B1 - Fuel Reformer And Manufacturing Method thereof - Google Patents

Abstract

The present invention relates to a fuel reformer and a method for manufacturing the same, and more particularly, a fuel reformer and a method for manufacturing the same, which enable efficient hydrogen production with a small amount of catalyst by alternately stacking an active catalyst core and an inert catalyst in consideration of a heat transfer effect. It is about.

In order to achieve the above object, the present invention provides a steam reforming fuel reformer (1), the fuel reformer (1) is a metal tube (11); An active catalyst core 12 stacked inside the tube 11 but stacked at a height lower than that of the tube 11; And an inert catalyst core 13 having a high thermal conductivity by being stacked inside the tube 11 after the active catalyst core 12.

In addition, the present invention provides a method for producing a fuel reformer for steam reforming, the first step of providing a metal tube (11); Stacking an active catalyst core (12) at a height lower than that of the tube (11) inside the tube (11); And a third step of stacking the inert catalyst core 13 having high thermal conductivity inside the tube after the active catalyst core 12.

Fuel cell, fuel reformer, catalyst, filling, active, inert, thermal conductivity

Description

Fuel reformer and manufacturing method thereof

The present invention relates to a fuel reformer and a method for manufacturing the same, and more particularly, a fuel reformer and a method for manufacturing the same, which enable efficient hydrogen production with a small amount of catalyst by alternately stacking an active catalyst core and an inert catalyst in consideration of a heat transfer effect. It is about.

A fuel cell is a power generation system that converts chemical energy into electrical energy by electrochemical reaction of hydrogen and oxygen to produce electricity and water as a byproduct. Such fuel cells are expected to replace internal combustion engines due to their excellent energy efficiency and are being actively researched and developed around the world.

Stable supply of hydrogen fuel is very important in fuel cells. As a method of supplying hydrogen to fuel cells, a method of storing hydrogen itself was also proposed at the beginning, but it is not easy to use for safety reasons, and most fuels containing hydrogen are reformed. Fuel reforming to produce hydrogen.

Hydrogen production by fuel reforming is known as Autothermal Reforming (ATR), Partial Oxidation (POX) and Steam Reforming (SR). Among them, the steam reforming method is mainly used for the advantage of achieving a high hydrogen yield, but the steam reforming reaction is a strong endothermic reaction due to its characteristics, so that the reaction occurs only when heat is supplied from the outside. As a method of supplying heat, a method of supplying heat by heating a furnace and flowing reaction heat obtained from external combustion around the reactor is mainly adopted. In addition, a method of raising the inlet temperature of the reforming hydrocarbon gas introduced into the reactor has also been sought as an alternative.

1 illustrates a conventional Haldor-Topsoe heat exchanger reformer 100. The hydrocarbon fuel gas flowing into the fuel inlet 140 passes through the primary catalyst 110 and the secondary catalyst 120 in sequence and is converted into hydrogen gas through steam reforming, and through the hydrogen outlet 141, the fuel reformer ( Exit 100) . The reaction heat for steam reforming reaction proceeding in the primary catalyst 110 and the secondary catalyst 120 is supplied through the burner 130 provided under the casing 150. In general, the fuel of the burner 130 uses synthetic gas, but there is also a method of mixing unreacted fuel from the fuel cell outlet side with air as shown in FIG. 1. The high temperature reaction gas generated by the burner 130 passes through the secondary catalyst 120 and the primary catalyst to the combustion gas outlet 131 and supplies the reaction heat to the reformed gas passing through the catalyst. At this time, the reactor tube 11 of the primary catalyst 110 and the secondary catalyst 120 should be selected as a material that is excellent in heat transfer characteristics and mechanical properties do not change even in a high temperature environment.

In general, the catalyst for steam reforming used up to now used a nickel (Ni) -based catalyst which is relatively inexpensive. Chromium and Group VIII precious metals are also active but relatively expensive. Nickel and ruthenium catalysts have catalytic properties that can convert methane even at relatively low temperatures of around 300 degrees.

However, nickel and ruthenium are still expensive despite their good catalytic properties. In the past, most of the research related to catalysts focused on improving the preparation method or activity of the catalyst in the chemical engineering area. Catalysts are usually mounted in several alloy reforming tubes, and these tubes are mounted and operated in a furnace, but tubular reformers are still one of the expensive devices. Therefore, efforts to reduce the number of tubes, reduce the amount of catalyst, reduce the size of the reactor, and reduce the manufacturing cost by improving the heat transfer efficiency are urgently needed.

The present invention is to solve the above problems, by presenting a new catalyst filling method to obtain a hydrogen yield of the same or higher than conventional, even with a small amount of catalyst, improve the heat transfer characteristics to improve the catalyst exchange cycle It is an object of the present invention to provide a catalyst filling method and a fuel reformer using the same.

In order to achieve the above object, the present invention provides a steam reforming fuel reformer (1), the fuel reformer (1) is a metal tube (11); An active catalyst core 12 stacked inside the tube 11 but stacked at a height lower than that of the tube 11; And an inert catalyst core 13 having a high thermal conductivity by being stacked inside the tube 11 after the active catalyst core 12.

Here, the active catalyst core 12 and the inactive catalyst core 13 is characterized in that the stack is alternately repeated two or more times.

On the other hand, it is preferable that the height of the repeatedly stacked active catalyst core 12 is not uniform.

Furthermore, it is even more preferable that the height of the repeatedly stacked active catalyst core 12 decreases from the inlet to the outlet of the tube 11 of the fuel reformer 1.

On the other hand, the tube 11 is characterized in that the material is selected from carbon steel, copper, stainless steel, Inconel, Incoloy or Hastelloy.

In addition, it is preferable that the inner surface of the tube 11 further includes a catalyst layer.

In addition, the inert catalyst core 13 is characterized in that it comprises a material selected from the alumina series.

In another aspect of the present invention, the present invention provides a method for filling a catalyst of a steam reformer for fuel reformer, comprising: a first step of providing a metal tube (11); A second step of stacking the active catalyst core 12 inside the tube 11 at a height lower than that of the tube 11; And a third step of stacking the inert catalyst core 13 having high thermal conductivity inside the tube after the active catalyst core 12.

In the filling method, it is preferable to repeat the second step and the third step two or more times.

In addition, it is preferable to use the active catalyst cores 12 having different heights in order to alternately repeat the filling.

Furthermore, it is much more advantageous to fill so that the heights of the different active catalyst cores 12 which are stacked in alternating fillings become smaller from the inlet to the outlet of the fuel reformer 1 tube 11.

According to the present invention, a catalyst charging method for a fuel reformer and a fuel reformer using the new type of fuel reformer can obtain an equivalent or excellent level of hydrogen yield even at a low catalyst production cost, and the heat transfer characteristics are improved to improve the fuel reformer. Long term driving performance is guaranteed.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings. Figure 2 is a partial cutaway perspective view of a fuel reformer according to the present invention, Figure 3a is a cross-sectional view of the fuel reformer and the present invention, Figure 3b is a temperature graph according to the length of the fuel reformer shown in Figure 3a, Figure 3c 3 is a graph showing the performance of the fuel reformer shown in Figure 3, Figure 4a is a cross-sectional view showing various forms of the fuel reformer according to the present invention, Figure 4b is a temperature graph according to the length of the fuel reformer shown in Figure 4a 4C is a graph showing the performance of the fuel reformer shown in FIG. 4A.

Matters that are not required as a part that is not different from the prior art are excluded from the description, but the technical spirit and protection scope of the present invention are not limited thereto.

The catalyst filling method of the present invention is characterized in that the active catalyst core 12 and the inert catalyst core 13 are alternately stacked in the metal tube 11. At this time, the inert catalyst core 13 has a high thermal conductivity, and refers to a general catalyst having excellent heat transfer efficiency in a longitudinal direction and a radial direction (addition) of the tube, but having deactivated catalyst properties for the reforming reaction.

The fuel reformer 1 to which the catalyst filling method of the present invention is applied will be described in more detail with reference to FIG. 2. The fuel reformer 10 of the present invention is manufactured by alternately stacking an active catalyst core 12 and an inert catalyst core 13 in a metal tube 11.

The tube 11 is preferably made of metal such that the heat of reaction required for steam reforming is transmitted from the outside in a state of low thermal resistance, and the material of the tube 11 may be carbon steel, copper, or stainless steel. It is furthermore preferred to be made of a material such as Inconel, Incolo or Hastelloy. The tube 11 needs to be designed to be as small as possible so long as there is no problem in mechanical strength.

It is preferable to form a noble metal or inorganic oxidation catalyst separately on the inner surface of the tube 11 to prevent deposition of reactants on the surface of the tube 11.

The active catalyst core 12 is used in a form supported on a ceramic foam or monolith carrier, and the method of supporting the catalyst on the monolith carrier may be a wash coating method. The wash coating method is a method of obtaining a catalyst core 12 by preparing a solution mixed with water and a binder, kneading the catalyst, stirring using a ball mill or the like, and dipping into a carrier or a monolith. Ceramic foams or monoliths are manufactured with high porosity to minimize pressure drop. As the material of the monolith, Al ₂ O ₃ , Ca-aluminate, MgO, or the like is suitable. When a catalyst such as Ni is used for the support, the reaction temperature is about 500 degrees or more.

On the other hand, the inert catalyst core 13 is filled with a material having no thermal activity but excellent thermal conductivity. It is preferable to use alumina as the inert material and excellent thermal conductivity, but the present invention is not limited thereto, and catalytic activity is decreased for the reforming reaction, but the thermal conductivity is high, and the thermal resistance is small in the length of the tube 11 and in the radial direction. If it is substance, it is enough. Meanwhile, the inactive core 13 may be an adsorbent or an absorbent having excellent thermal conductivity.

The catalyst support plate 14 supports the active catalyst core 12 and the inert catalyst core 13 which are stacked in the vertical direction, so that the screen, mesh, perforated plate or It is preferred to produce in the form of porous sintered metal plates. The material may be made of stainless steel, Inconel, Hastelloy or any suitable ceramic material. In addition to supporting the catalyst cores 12 and 13, the catalyst support plate 14 also serves as an induction plate for inducing the reforming reactant to spread evenly through the tube 11 cross section.

In addition, the catalyst support plate 14 may be provided at the outlet side of the tube 11, as shown in FIG. 2, and is also provided in the middle of the active catalyst core 12 or the inactive catalyst core 13. Of course, the formation thickness and number of the catalyst support plate 14 should be formed within a range that does not prevent the movement of the reforming gas.

The catalyst of the present invention is produced by alternately stacking the active catalyst core 12 and the inactive catalyst core 13. The number of laminations may vary as needed. That is, the stacking may be alternately performed one time as shown in case 4 or case 5 shown in FIG. 4A. If the length of the tube 11 is considerably long and the uniformity of temperature is important, the number of stacking may be increased as in case 6. Can be. The number of laminations is preferably optimized according to the length of the tube 11 and the reaction temperature.

Meanwhile, the heights of the active catalyst cores 12 (b, d, f in FIG. 2) and the heights of the inactive catalyst cores 13 (a, c, e in FIG. 2) do not need to be the same.

As shown in FIG. 2, the height of the active catalyst core 12 refers to the height along the longitudinal direction of the tube 11, and the fuel reformer 1 of the present invention has a temperature in the longitudinal direction of the tube 11. To reduce the deviation, the height can be set in the order of b> d> f. The height of the inert catalyst core 13 may also be determined differently in a similar manner. Methods of varying the height of the active catalyst core 12 and the inactive catalyst core 13 are all within the technical scope of the present invention.

Next, the specific effects of the present invention will be described in detail with reference to FIGS. 3 and 4. 3A is a sectional view of a fuel reformer 1 manufactured by the conventional catalyst lamination methods case1 and 2 and the lamination method case3 of the present invention. Conventional fuel reformer (1) is to manufacture a catalyst to support the whole in the tube (11) is to be provided with the active catalyst core 12 of the present invention in the tube (11) as a whole, the present invention is As described above, the inert catalyst core 13 and the active catalyst core 12 are alternately stacked. In order to clarify the discussion, the case of the present invention (case) was tested assuming a case of stacking only one stage.

In FIG. 3A, the vertical arrow indicates heat applied to the outer wall of the tube 11 and indicates the intensity of heat applied along its length.

In addition, it is common to adopt a linearized heat transfer pattern such as case 2 in order to closely simulate the phenomena carried by the combustion gas, but for the comparative experiments, the total heat transfer amount is the same but has a constant heat flux rather than a linear shape. Including case1 was examined. The reformed gas is introduced into the catalyst core 12 at the left inlet, reformed, and exits through the right outlet.

In order to confirm the superiority of the lamination method, the temperature distribution inside the catalyst and the mole ratio of hydrogen to hydrocarbons added were observed.

As shown in FIG. 3c in FIG. 3c along the longitudinal direction of the tube 11, it is confirmed that the number of moles of hydrogen produced relative to hydrocarbons is about the same level for the same heat flux. The fact that a small amount (case 3, 50%) of catalyst was obtained and hydrogen yields similar to those obtained by the conventional filling method (case 2) was proved to be quite effective in the packing method of the present invention. That is, by integrating the inert catalyst core 13, which is inert but has excellent thermal conductivity, with the active catalyst core 12, the heat transfer can be smoothly achieved.

In Figure 3b it can be seen how the temperature varies depending on the characteristic length of the catalyst tube (11). In the case of the conventional filling method, the temperature rises relatively uniformly along the length, whereas in the case of the filling method of the present invention, the temperature rises rapidly in the early stage and becomes equivalent to the conventional method in the second half.

However, the temperature distribution as in the case of 50% filling of case 3 shown in FIG. 3 has no good influence on the mechanical strength of the fuel reformer 1 including the catalyst cores 12 and 13 and the tube 11. In other words, the temperature difference between the catalyst layers is large, which shortens the life, which means that the catalyst must be replaced in a shorter period. A catalyst in the form of a reforming tube having a tube (11) is usually designed based on 100,000 hours. When the temperature of the reforming tube decreases by about 20 degrees, it is known that the life of the reforming tube is doubled. In this respect, the temperature deviation in the longitudinal direction becomes even more problematic.

In order to reduce the temperature deviation in the longitudinal direction of the tube 11, the present invention further provides a filling method of case 6 as disclosed in FIG. 4A. That is, the fuel reformer 10 of the present invention alternately stacks the active catalyst core 12 and the inactive catalyst core 13, but increases the number of stacks.

In addition, the fuel reformer 1 of the present invention is provided with the active catalyst core 12 and the inert catalyst core 13 alternately as shown in case 4 of FIG. 4A, and the active catalyst core 12 is It is provided at the rear end of the tube 11 and the inert catalyst core 13 may be provided at the front end of the tube 11 (in this case, case 4 of FIG. 4A is 50% of case3 of FIG. 3B). As shown in case 5 of FIG. 4B, the active catalyst core 12 is provided at the front end of the tube 11 and the inactive catalyst core 13 is formed at the rear end of the tube 11. It may be provided in.

Figure 4b is a graph showing the temperature distribution according to the characteristic length of the tube 11 of the fuel reformer shown in Figure 4a, Figure 4c shows the hydrogen yield performance, as can be seen in Figure 4 the activity repeatedly In the case 6 in which the catalyst core 12 and the inert catalyst core 13 are stacked, it can be seen that the temperature deviation is significantly reduced in the longitudinal direction. As a result, according to the filling method of the catalyst according to the present invention, it is possible to manufacture a high quality fuel reformer 1 having a lower catalyst yield than the conventional catalyst and having a large temperature deviation.

On the other hand, the manufacturing method of the fuel reformer (1) of the present invention, the method for producing a steam reforming fuel reformer (1), comprising: a first step of providing a metal tube (11); A second step of stacking the active catalyst core 12 inside the tube 11 at a height lower than that of the tube 11; And a third step of stacking the inert catalyst core 13 having high thermal conductivity inside the tube after the active catalyst core 12.

In addition, the active catalyst core 12 and the inactive catalyst core 13 may repeat the second and third steps two or more times by adjusting the height stacked on the tube 11, the height of the It can also be formed differently.

At this time, the active catalyst core 12 is preferably formed to be smaller as it proceeds from the inlet to the outlet side of the tube (11).

The present invention is not limited to the above-described embodiments, and the scope of application is not limited, and various modifications can be made without departing from the gist of the present invention as claimed in the claims.

According to the catalyst filling method for a fuel reformer of the present invention, it is possible to produce a catalyst core of low cost and high efficiency which can obtain hydrogen yields of the same level or higher with a small amount of catalyst. The filling method can be applied not only to steam reforming but also to the production of catalyst tubes in which heat transfer is important.

1 is a schematic cross-sectional view of a conventional Haldor-Topsoe heat exchanger type reformer.

2 is a partially cutaway perspective view of a fuel reformer according to the present invention;

3A is a cross-sectional view of the present invention and a conventional fuel reformer.

Figure 3b is a graph of the temperature according to the length of the fuel reformer shown in Figure 3a.

3C is a graph showing the performance of the fuel reformer shown in FIG. 3.

Figure 4a is a cross-sectional view showing various forms of a fuel reformer according to the present invention.

4b is a temperature graph according to the length of the fuel reformer shown in FIG. 4a.

4C is a graph showing the performance of the fuel reformer shown in FIG. 4A.

** Description of the symbols for the main parts of the drawings **

1: fuel reformer

11 tube 12 active catalyst core

13 inert catalyst core 14 catalyst support plate

Claims (11)

A steam reformer (1) for reforming steam, the fuel reformer (1) comprising: a metal tube (11); An active catalyst core 12 stacked inside the tube 11 but stacked at a height lower than that of the tube 11; And an inert catalyst core (13) having high thermal conductivity by being stacked in the tube (11) after the active catalyst core (12); A fuel reformer comprising a. The fuel reformer of claim 1, wherein the active catalyst core (12) and the inactive catalyst core (13) are repeatedly stacked alternately two or more times. 3. The fuel reformer of claim 2, wherein the height of the repeatedly stacked active catalyst cores is not uniform. 4. The fuel reformer according to claim 3, wherein the height of the repeatedly stacked active catalyst core (12) decreases from the inlet to the outlet of the fuel reformer tube (11). 5. The fuel reformer according to any one of claims 1 to 4, wherein the tube (11) is made of a material selected from carbon steel, copper, stainless steel, inconel, incolo or hastelloy. 6. The fuel reformer of claim 5, wherein the inner surface of the tube (11) further comprises a catalyst layer. The fuel reformer according to any one of claims 1 to 4, wherein the inert catalyst core (13) comprises a material selected from alumina series. A method for producing a steam reformer for fuel reforming, the method comprising: a first step of providing a metal tube (11); Stacking an active catalyst core (12) at a height lower than that of the tube (11) inside the tube (11); And a third step of stacking an inert catalyst core (13) having a high thermal conductivity in the tube after the active catalyst core (12). 9. The method of claim 8, wherein the second and third steps are repeated two or more times. 10. The method of producing a fuel reformer according to claim 9, characterized in that the filling is performed by using active catalyst cores having different heights in alternating filling. 11. The fuel according to claim 10, wherein the heights of the different active catalyst cores 12 stacked in alternating filling are reduced so as to decrease from the inlet to the outlet of the tube 11 of the fuel reformer 1. Method of making a reformer.

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