JP2659841B2 - Methanol reformer - Google Patents

Description

The present invention relates to a methanol reformer, and more particularly, to a methanol reformer.
The present invention relates to a methanol reformer for reforming into a hydrogen-containing gas by bringing methanol or methanol and water into contact with a catalyst.

[Conventional technology]

One embodiment of a conventional method for producing a hydrogen-containing gas by reforming methanol will be described with reference to FIG. An apparatus for implementing this embodiment includes a raw material pump 1 for supplying methanol and pure water, a raw material preheater 2 for evaporating the raw material and raising the temperature to a reaction temperature, a superheater 5, a reactor 4 having a reaction tube filled with a catalyst, A cooler 3 for condensing the reaction raw materials and the like, a gas-liquid separator 8 for gas-liquid separation of the condensate, a heating medium heater 7 and a heating medium circulation pump 6 for supplying heat required for the reaction, a purification for purifying a gas as a product It is constituted by a vessel 9.

The raw material supplied under pressure by the raw material pump 1 is heated to a predetermined temperature by a raw material preheater 2 and a superheater 5, and a mixed vapor of methanol and water is reformed into a hydrogen-containing gas in a reactor 4 filled with a catalyst. You.

The term "hydrogen-containing gas" used herein refers to a gas containing at least 50 mol% (dry basis) of hydrogen. The main components of the gas other than hydrogen are carbon dioxide (CO ₂ ) and carbon monoxide (CO). The gas concentration is determined by the yield of the following three reactions.

CH ₃ OH → 2H ₂ + CO CH ₃ OH + H ₂ O → (2 + n) H ₂ + (1-n) CO + nCO ₂ (0 <n <1) CH ₃ OH + H ₂ O → 3H ₂ + CO ₂ These reactions are endothermic reactions. Therefore, heat is supplied by the heat medium heated by the heat medium heater 7. The unreacted raw material condensed in the cooler 3 is recovered in the gas-liquid separator 8, returned to the raw material line, and circulated. The produced gas is purified and recovered as a product gas.

As described above, the reaction is an endothermic reaction, and the reactor 4 is of a shell-and-tube heat exchanger type. The tube is filled with a catalyst, and the raw material supplied to the catalyst layer is brought into contact with the catalyst. It is reformed into a hydrogen-containing gas by the reaction. This reaction heat is supplied from the heat medium on the shell side. Since the above reaction on the catalyst is relatively slow, the rate of hydrogen generation in the reaction tube is controlled by heat transfer.To improve heat transfer, the reaction tube is
It is as thin as 20 to 40 mm, generally 30 mm.

Therefore, the number of reaction tubes becomes very large, and a large amount of labor is required for the catalyst filling operation. In addition, since it is a multi-tube type, the volume on the shell side becomes large structurally, and the equipment becomes large.

On the other hand, a complicated structure such as providing a partition plate for improving the heat transfer coefficient on the heat medium side is required. Further, a heat medium unit is required for replenishing the reaction heat, and these increase the cost of the product gas.

[Problems to be solved by the invention]

An object of the present invention is to solve the above-mentioned drawbacks of the conventional method and to provide a compact and inexpensive apparatus for reforming methanol.

[Means for solving the problem]

The present invention relates to an apparatus for reforming methanol into a hydrogen-containing gas, in which a large number of plates having one surface formed as a catalyst for methanol reforming and the other surface formed as an oxidation catalyst are formed so that the methanol reforming catalysts and the oxidation catalysts face each other. A methanol reformer characterized in that methanol and water are passed through the gap between the methanol reforming catalysts, and fuel gas and air are passed through the gap between the oxidation catalyzing surfaces. It is.

[Action]

The plate heat exchanger type reactor having both sides of a plate having a catalytic function according to the present invention is a multi-flow channel type, a cross flow type,
There is a countercurrent type, but the catalyst component is treated on both sides of these plates by plating, spraying, vapor deposition, coating and other methods,
The plate itself is catalyzed.

The catalyzed heat transfer plate is characterized in that the heat transfer surface itself is a catalyst surface accompanied by reaction heat, and has a large heat transfer. Further, since both surfaces of the plate according to the present invention are catalyzed, a methanol reforming reaction, which is an endothermic reaction, is carried out in a reaction section (a process gas flow path on the surface catalyzed by reforming, hereinafter referred to as a reaction section). Then, the reaction heat is utilized by utilizing heat generated by catalytic combustion of fuel gas and air in a heating section (a fuel gas flow path on an oxidation-catalyzed surface, hereinafter referred to as a heating section).

That is, the size of the reformer is reduced by efficient heat transfer by utilizing the balance of heat generated by the endothermic and exothermic reactions on both sides of the plate.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a main part of a cross-flow plate heat exchanger type reactor, in which a reaction section and a heating section are sandwich type for each layer.

FIG. 2 is a process flow using a plate heat exchanger type reactor having a catalytic function and using fuel gas as a heat source. The components of the process flow shown in FIG.
A raw material pump 1 for supplying pure water, a raw material preheater 2 for preheating raw materials with product gas, an evaporator 10 for evaporating raw materials, a plate heat exchanger type reactor 4 having a plate having a catalytic function, and a product gas It comprises a cooler 3 for cooling, a gas-liquid separator 8 for separating condensed components in the product gas, and a purifier 9 for purifying the product gas from which the condensed components have been separated.

FIG. 3 shows a process flow using a plate heat exchanger type reactor in which the raw material evaporator 10, the raw material superheater 5, and the reactor 4 are sequentially arranged according to the temperature level of the fuel gas. This is a small and high-performance methanol reformer.

Further, the term "fuel gas" as used in the present invention is a general term for a gas capable of introducing air and catalytically combusting, for example, a gas containing methanol vapor or hydrogen.

The following catalyst components are suitable as the catalyst components that can be used in the apparatus of the present invention.

(1) Methanol reforming catalyst component A catalyst component containing one or more elements of the group consisting of Pt, Pd, Rh, and Ni A catalyst component containing one or more elements of the group consisting of Cu, Zn, and Cr (2) Combustion Catalyst component containing one or more elements of the group consisting of Pt and Pd Catalyst component containing one or more elements of the group consisting of Fe, Ni, Co, Mn and Cu [Example 1] As shown in the figure, methanol was added to the reaction section of the plate heat exchanger type reactor shown in FIG.
g / h, a pure water supplying raw material 2.7 kg / h, the fuel gas in the heating section (H ₂ to about 66 mol%, the other _{H 2 O, CO 2 CO)} 3Nm 3 / h, air 14 Nm ³ / h supplied A methanol reforming reaction was performed. Alumina whiskers are formed on the plate surface of the reaction section and heating section of the plate heat exchanger reactor. A wash coat of alumina is applied on the whisker, and a dinitrodiammineplatinum (II) nitrate acid solution of a predetermined concentration is applied. , And dried and fired, and then reduced with hydrogen to carry platinum. The fuel gas and air are passed through the heating section to perform catalytic combustion on the platinum catalyst, and the generated heat is used as a heat source. On the opposite side of the plate, the raw materials were introduced and heated to the reaction temperature, and a reforming reaction was performed in which the main reaction was a methanol decomposition reaction, an endothermic reaction, on a platinum catalyst in the reaction section.
The results shown in Table 1 were obtained.

Example 2 Methanol, pure water, fuel gas and air were supplied to the plate heat exchanger type reactor shown in FIG. 3 under the same conditions as in Example 1 to carry out a methanol reforming reaction.

The plate in the heating section of the plate heat exchanger reactor carries platinum in the same manner as in Example 1. The reaction plate is sprayed with a composite oxide containing a specified concentration of nickel and copper on the high temperature side (combustion exhaust gas inlet side) plate, and copper and zinc on the low temperature side (combustion exhaust gas outlet side). Using a plate heat exchanger type reactor in which plates sprayed with a composite oxide containing a predetermined concentration are placed, a fuel reforming reaction is performed by passing fuel gas and air to the heating section and methanol and water to the reaction section. As a result, the results shown in Table 2 were obtained.

[Effect of the Invention] By using a plate heat exchanger type reactor using a plate having a catalytic function instead of a conventional tubular reactor, a small and high performance methanol reforming reaction can be achieved. Because it can be performed and does not form a packed bed of the particulate catalyst,
Since there is no pressure loss and the fuel gas can be used efficiently as a heat source, the cost can be reduced and its industrial value is extremely high.

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment of the apparatus of the present invention, FIGS. 2 and 3 are process flow diagrams showing an embodiment of a method of using the apparatus of the present invention for methanol reforming, and FIG. FIG. 3 is a process flow chart of a methanol reforming method using a vessel.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B01J 35/02 C01B 3/32 A C01B 3/32 31/20 A 31/20 C10K 3/04 C10K 3/04 B01J 23/74 321M

Claims (1)

(57) [Claims] 1. An apparatus for reforming methanol into a hydrogen-containing gas, wherein a large number of plates having one surface catalyzed by methanol reforming and the other surface oxidized by catalysis are treated with methanol reforming catalyzed and oxidized catalyzed one by one. Methanol and water are passed through the gap between the methanol reforming catalysts, and the fuel gas and air are passed through the gap between the oxidation catalyzing faces. Quality equipment.