JP2008138153A - Desulfurization process, desulfurization apparatus, manufacturing equipment of reformed gas for fuel cell and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system equipped with a desulfurization apparatus that can perform a desulfurization treatment stably for a long period of time. <P>SOLUTION: The upstream side desulfurizer 310, which is filled with an upstream side desulfurizing agent of at least either of a zeolite desulfurizing agent and a metal oxide, is connected in series with the desulfurizer 320 filled with a stabilized desulfurizing agent, herein the zeolite desulfurizing agent being one having at least any one selected from silver, nickel, copper, iron, manganese, cobalt, cerium and lanthanum supported on an inorganic material, the metal oxide being at least any one selected from nickel, copper, iron, manganese, cobalt, cerium and lanthanum, and the stabilized desulfurizing agent containing at least any one selected from iron, nickel, copper, cobalt and manganese. After the stabilized desulfurizing agent is subjected to reduction treatment at a temperature near to ordinary temperature, the raw material gas is subjected to ordinary temperature desulfurization treatment in the upstream side desulfurizer 310, subjected to desulfurization treatment at 50-400°C in the desulfurizer and subjected to reformation treatment in the reformer 410. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a desulfurization method, a desulfurization apparatus, an apparatus for producing a reformed gas for a fuel cell, and a fuel cell system, which desulfurize a raw material gas containing a hydrocarbon raw material with a desulfurizing agent filled therein.

In recent years, new energy technology has attracted attention due to environmental problems, and fuel cells are attracting attention as one of the new energy technologies. This fuel cell converts chemical energy into electric energy by electrochemically reacting hydrogen and oxygen, and has a feature of high energy use efficiency. Research into practical application in various fields such as for automobiles has been actively conducted.
Various types of fuel cells such as a phosphoric acid type, a molten carbonate type, a solid oxide type, and a solid polymer type are known according to the type of electrolyte used. On the other hand, as a hydrogen source, liquefied natural gas mainly composed of methanol and methane, city gas mainly composed of this natural gas, synthetic liquid fuel using natural gas as a raw material, liquefied petroleum gas (LPG), dimethyl ether, The use of petroleum hydrocarbons such as naphtha and kerosene has been studied. When hydrogen is produced using these gaseous or liquid hydrocarbons, the hydrocarbon is generally reformed in the presence of a reforming catalyst by partial oxidation reforming, autothermal reforming or steam reforming. A method has been implemented. And when reforming hydrocarbons such as LPG, city gas, and kerosene to produce hydrogen for fuel cells, in order to prevent poisoning of the reforming catalyst, the sulfur content in the hydrocarbon is 0.01 ppm. It is necessary to reduce to the following. As the removal of the sulfur content, a configuration in which desulfurization treatment is performed in multiple stages is known (see, for example, Patent Document 1 and Patent Document 2).

The thing of patent document 1 combines a normal temperature adsorption desulfurizer and a heat desulfurizer, and distribute | circulates hydrocarbons sequentially through a normal temperature adsorption desulfurizer and a heat desulfurizer, and removes sulfur compounds, such as a carbonyl sulfide.
And the structure using the crystalline silicate which carry | supported the zinc oxide type catalyst, the copper type catalyst, and the catalytically active metal as a desulfurization agent with which a heating desulfurizer is filled is taken.

The thing of patent document 2 combines a normal temperature adsorption desulfurizer and a heat | fever desulfurizer, distribute | circulates LPG sequentially to a normal temperature adsorption desulfurizer and a heat desulfurizer, and removes a sulfur compound.
And the structure which uses a nickel-type desulfurization agent and a copper-type desulfurization agent as a desulfurization agent with which a heating desulfurizer is filled is taken.

JP 2006-96623 A JP 2006-111766 A

  However, even in the conventional configuration as described in Patent Document 1 and Patent Document 2, the removal amount of the sulfur compound is not sufficient, causing inconvenience such as shutdown due to a decrease in the activity of the desulfurizing agent, and desulfurization more than necessary. There is a risk of increasing the size of the desulfurizer by using the agent. Therefore, longer life of the desulfurizing agent is desired.

  In view of these points, an object of the present invention is to provide a desulfurization method, a desulfurization apparatus, a production apparatus for a reformed gas for a fuel cell, and a fuel cell system capable of obtaining a desulfurization treatment that is stable for a long time.

The desulfurization method described in the present invention is a desulfurization method in which a raw material gas containing a hydrocarbon raw material is desulfurized with a desulfurizing agent, and the desulfurized raw material gas is heated under a reforming catalyst to contain hydrogen gas. Stabilization that is connected in series to the upstream side where the raw material gas flows in a reformer that generates a gaseous gas, and is at least one selected from iron, nickel, copper, cobalt, and manganese and is partially in a metallic state The raw material gas is desulfurized at 50 ° C. or higher and 400 ° C. or lower with the desulfurizer filled with the desulfurized agent.
In this invention, the desulfurized raw material gas is heated under a reforming catalyst and is located upstream of the raw material gas in a reformer that generates a reformed gas containing hydrogen gas. At least one selected from copper, cobalt and manganese, in particular, a desulfurizer filled with a stabilized desulfurizing agent partially in a metallic state with nickel is connected in series, and is preferably 50 ° C. or higher and 400 ° C. or lower, preferably Performs desulfurization treatment of the raw material gas with a desulfurizing agent at 100 ° C. or higher and 300 ° C. or lower.
Here, the predetermined metal can adsorb and remove sulfur at a very low concentration by chemical adsorption at a temperature of room temperature or higher. For example, a desulfurization agent in which a part of the metal oxide is in a metal state can easily reduce the metal oxide to metal even at room temperature. As a result, by bringing the raw material gas into contact with the desulfurization agent reduced to a predetermined metal at a temperature of 50 ° C. or higher and 400 ° C. or lower, the sulfur content in the raw material gas can be adsorbed and removed efficiently, and the advanced desulfurization treatment is long. It can be obtained stably for a period of time, and efficient operation can be obtained. Furthermore, the miniaturization can be easily achieved by using the minimum necessary desulfurizing agent.
And if the temperature at the time of desulfurization becomes lower than 50 degreeC, the adsorption capacity by a desulfurization agent will decrease, the amount of desulfurization agents required will increase, and a highly efficient desulfurization process will not be obtained. On the other hand, when the temperature is higher than 400 ° C., hydrocarbon coking occurs, which may cause inconveniences such as a desulfurization function being lowered or a pipe being blocked. Thus, the desulfurization treatment is performed at 50 ° C. or higher and 400 ° C. or lower, preferably 100 ° C. or higher and 300 ° C. or lower.

And in this invention, it is a desulfurization method of Claim 1, Comprising: The said stabilized desulfurization agent is at least among the metal by which the surface was oxidized to the oxide, and the metal processed with the carbon dioxide gas It is preferable that either one be configured.
In the present invention, as the stabilized desulfurizing agent, at least one of a metal whose surface is oxidized to an oxide and a metal treated with carbon dioxide gas is used.
This facilitates handling and reduction treatment before the desulfurization treatment, and an efficient and easy desulfurization treatment is obtained.

Further, in the present invention, the desulfurization method according to claim 1 or 2, wherein the stabilized desulfurizing agent is reduced in a temperature range of normal temperature to 300 ° C. before desulfurization treatment of the raw material gas. It is preferable to adopt a configuration for processing.
In the present invention, before the raw material gas is desulfurized, the stabilized desulfurizing agent is reduced in a temperature range of normal temperature to 300 ° C. Although it is preferable to perform the reduction treatment at a relatively high temperature, it is sufficient to carry out the reduction treatment at room temperature.
This makes it possible to obtain a metal catalyst that can be highly desulfurized simply by supplying a reducing gas such as hydrogen, for example, by introducing hydrogen into the hydrogen, and can easily and efficiently perform advanced desulfurization treatment. It is done. In addition, since it is a desulfurization process for generating a reformed gas used for power generation in a fuel cell, no special treatment is required even if hydrogen gas is supplied to reduce the desulfurizing agent, and hydrogen is mainly used as the reduction. By supplying a reducing gas as a component, efficient and advanced desulfurization treatment can be obtained more easily. In particular, the reduction treatment at room temperature eliminates the need for heating, thus saving energy, eliminating the need to provide heating means, simplifying the configuration, and easily reducing the size of the apparatus configuration.

Furthermore, in this invention, it is a desulfurization method in any one of Claim 1 thru | or 4, Comprising: The said desulfurizer is after desulfurizing using the upstream desulfurizer which desulfurizes the said raw material gas at normal temperature. The raw material gas is preferably desulfurized.
In the present invention, the raw material gas is desulfurized at room temperature by the upstream desulfurizer, and then heated and desulfurized by the desulfurizer.
As a result, after the sulfur content in the raw material gas is desulfurized to some extent at room temperature in the upstream desulfurizer, the desulfurization treatment with a predetermined metal of the desulfurizer that can be highly desulfurized is performed, so the load of the desulfurizing agent is reduced, A high degree of desulfurization treatment can be stably obtained for a long time even with a small amount of desulfurization agent.

In the present invention, the desulfurization method according to claim 5, wherein the upstream desulfurizer is made of at least one metal selected from silver, nickel, copper, iron, manganese, cobalt, cerium, and lanthanum. A structure in which at least one of a zeolite desulfurization agent supported on an inorganic material and at least one metal oxide selected from nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is filled. It is preferable.
In the present invention, the upstream desulfurizer includes a zeolite desulfurization agent in which at least one kind of metal selected from silver, nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is supported on an inorganic material, nickel, copper And at least one of at least one metal oxide selected from iron, manganese, cobalt, cerium, and lanthanum.
As a result, as an upstream desulfurizer that removes a certain amount of sulfur in the raw material gas, at least the zeolite desulfurization agent in which the predetermined metal is supported on an inorganic material, and the metal oxide of the predetermined metal described above Since either one is used, a desulfurization agent that is relatively easy to manufacture and handle and can be manufactured at low cost is used, so that more efficient desulfurization treatment can be easily obtained.

And in this invention, it is a desulfurization method of Claim 5 or Claim 6, Comprising: It is preferable to set it as the structure by which the said upstream desulfurizer is detachably arrange | positioned in the distribution path of the said source gas. .
In this invention, the upstream desulfurizer is detachably disposed in the flow path of the raw material gas.
This makes it possible to attach and detach a desulfurizer with a simple configuration that removes a certain amount of sulfur content in the raw material gas at room temperature, that is, by replacing the upstream side, which is a pre-stage of the desulfurization process. It can be easily obtained by simply replacing the desulfurizer.
In particular, it is preferable to provide an automatic closing function that connects to the flow path by connection and closes the flow path by removal, thereby preventing problems caused by air flowing into the flow path and the desulfurizer during removal.

Further, in the present invention, the desulfurization method according to any one of claims 1 to 7, wherein the desulfurizer uses a deoxygenation means for removing oxygen mixed in the flowing raw material gas. It is preferable that the removed raw material gas is desulfurized.
In this invention, after removing oxygen mixed in the raw material gas distributed by the deoxygenation means, the heat desulfurization treatment is performed by the desulfurizer.
As a result, even if air or the like is mixed into the raw material gas flow path due to, for example, replacement of the raw material gas cylinder, oxygen is removed by the deoxidizing means. It can prevent that a desulfurization activity falls because an agent is oxidized with the oxygen which mixes.

Furthermore, in this invention, it is the desulfurization method in any one of Claim 1 thru | or 8, Comprising: The said desulfurizer is the said reformed gas which produced | generated the said stabilized desulfurizing agent with the said reformer. It is preferable to fill 2 ml or more and 100 ml or less per 1 kW of power generation in a fuel cell that generates electricity using as a raw material.
In the present invention, as the desulfurization agent stabilized in the desulfurizer, 2 ml or more and 100 ml or less are charged per 1 kW of power generation in the fuel cell that generates power using the reformed gas generated in the reformer as a raw material.
As a result, the required amount of desulfurization agent that can be stably desulfurized stably for a long period of time may be used, and the apparatus can be downsized, the heating means can be simplified, and the heat loss can be easily reduced.
Here, if the power generation amount is less than 2 ml per 1 kW, there is a possibility that advanced desulfurization treatment cannot be obtained for a long time. On the other hand, when the amount of power generation exceeds 100 ml per 1 kW, the filling space increases, leading to an increase in the size of the apparatus, and even though sufficient desulfurization performance remains, other parts such as a reforming catalyst have a lifetime, May not be economical. For this reason, the stabilized desulfurizing agent is set to 2 ml to 100 ml per 1 kW of power generation in the fuel cell.

A desulfurization apparatus according to the present invention is a desulfurization apparatus in which a desulfurization agent for desulfurizing a raw material gas containing a hydrocarbon raw material is filled, and at least one metal selected from iron, nickel, copper, cobalt, and manganese is used. The desulfurized raw material gas having an accommodation space filled with a stabilized desulfurizing agent, and having an inlet port through which the raw material gas flows and an outlet port through which the raw material gas flows out of the housing space. A container connected in series to the upstream side where the raw material gas flows in a reformer that generates a reformed gas containing hydrogen gas by heating under a reforming catalyst, and the inflowing raw material gas Heating means for heating to 50 ° C. or higher and 400 ° C. or lower and desulfurizing with the desulfurizing agent.
The present invention is an apparatus in which the desulfurization method according to claim 1 is developed in an apparatus configuration, in a reformer that heats a desulfurized raw material gas under a reforming catalyst to generate a reformed gas containing hydrogen gas. Located at the upstream side where the raw material gas is introduced, filled with at least one selected from iron, nickel, copper, cobalt, and manganese, in particular, a stabilized desulfurization agent partially in a metallic state with nickel The containers are connected in series, and the raw material gas is desulfurized with a desulfurizing agent at 50 ° C. or higher and 400 ° C. or lower, preferably 100 ° C. or higher and 300 ° C. or lower, by heating means.
And in this invention, there exists an effect similar to the desulfurization method of Claim 1.

  Further, the desulfurization apparatus according to claims 11 to 16 and claim 18 dependent on claim 10 is developed from the desulfurization method according to claims 2 to 9 dependent on claim 1, respectively. Thus, the same effects as those of the desulfurization method according to claims 2 to 9 are obtained.

Furthermore, in this invention, it is a desulfurization apparatus of Claim 16, Comprising: The said deoxygenation means is provided with the joint part which has the automatic closing function arrange | positioned so that attachment or detachment is possible in the distribution path of the said source gas. It is preferable that
According to the present invention, the deoxygenating means is detachably disposed at the joint portion having an automatic closing function in the flow path of the raw material gas.
As a result, inconvenience due to air flowing into the flow path of the raw material gas and the desulfurizer when the deoxygenating means is removed can be easily prevented with a simple configuration, and a good desulfurization treatment can be easily obtained.

The apparatus for producing a reformed gas for a fuel cell according to the present invention comprises a raw material gas supply means for supplying a raw material gas containing a hydrocarbon raw material, and a desulfurization treatment of the raw material gas supplied from the raw material gas supply means. A desulfurization apparatus according to any one of claims 18 to 18, and a reformer charged with a reforming catalyst that heats the raw material gas desulfurized by the desulfurization apparatus to reform the reformed gas containing hydrogen gas. And a container.
In this invention, the raw material gas containing the hydrocarbon raw material supplied from the raw material gas supply means can highly adsorb and remove the sulfur content in the raw material gas efficiently, and a high degree of desulfurization treatment can be stably obtained over a long period of time. The desulfurization treatment is performed by the desulfurization apparatus according to any one of claims 10 to 18, which can provide a simple operation and can be easily downsized. Then, the raw material gas subjected to the desulfurization treatment is heated by a reformer and reformed to a reformed gas containing hydrogen gas by a reforming catalyst.
As a result, the production of reformed gas stable for a long time can be obtained with a small-sized apparatus.

And in this invention, it is a manufacturing apparatus of the reformed gas for fuel cells of Claim 19, Comprising: The said raw material gas supply means is an automatic sealing function to which the raw material tank which stores raw material gas is connected so that attachment or detachment is possible It is preferable to have a configuration including a joint portion having
In this invention, the source gas is supplied by detachably connecting the source gas tank storing the source gas by the joint portion having the automatic sealing function of the source gas supply means.
This makes it possible to use a raw material tank that can be easily replenished with a raw material gas and is widely used. For example, it can be used as a raw material gas supply in a household fuel cell, and can be used easily. Replenishment and supply can be easily performed, and stable reformed gas supply can be easily obtained, and inconvenience due to air flowing into the flow path and desulfurizer when the raw material tank is removed can be easily configured Can be prevented, and a good desulfurization treatment can be easily obtained.

A fuel cell system according to the present invention comprises a fuel cell reformed gas production apparatus according to claim 19 or claim 20, an oxygen-containing gas supply means for supplying an oxygen-containing gas, and the fuel cell reforming. And a fuel cell that generates electric power using the reformed gas reformed by the reformer of the gas production apparatus and the oxygen-containing gas supplied by the oxygen-containing gas supply means. To do.
In this invention, the production of reformed gas stable for a long period of time is supplied from the reformed gas from the fuel cell reformed gas production apparatus according to claim 19 or claim 20 and the oxygen-containing gas supply means. Using the oxygen-containing gas, the fuel cell generates power.
Thus, stable power generation for a long time can be obtained with a small device.

Hereinafter, an embodiment according to the fuel cell system of the present invention will be described.
In the present embodiment, the configuration of the fuel cell system using the hydrocarbon raw material provided with the desulfurizer of the present invention is illustrated, but the configuration is not limited to the configuration used for the fuel cell system, for example, a reformed gas production apparatus The present invention can be applied to various configurations for desulfurizing a raw material gas containing a hydrocarbon raw material, such as a purification apparatus, a supply apparatus, and the like. Furthermore, the present invention can be applied not only to a small system configuration for home use, but also to a relatively large system configuration used for collective housing and various stores.
FIG. 1 is a block diagram showing a schematic configuration of a fuel cell system according to the present embodiment.

[Configuration of fuel cell system]
(overall structure)
In FIG. 1, reference numeral 100 denotes a fuel cell system. The fuel cell system 100 uses a raw material gas containing a hydrocarbon raw material as a raw material, and reforms it into a fuel gas that is a reformed gas containing hydrogen as a main component. 200 is a system for generating electricity.
Here, examples of the raw material gas include liquefied natural gas mainly composed of methanol and methane, city gas mainly composed of natural gas, synthetic liquid fuel using natural gas as a raw material, and liquefied petroleum gas (LPG). Gasified petroleum hydrocarbons such as dimethyl ether, naphtha and kerosene can be used.

The fuel cell system 100 includes a raw material gas supply means 110 that constitutes a distribution path that is a pipe for supplying a raw material gas. As the source gas supply means in the present invention, any configuration for supplying a source gas containing a hydrocarbon source, such as a configuration including a vaporizer for supplying a gaseous source gas from an installed cylinder or tank, for example, is applied. it can.
The raw material gas supply means 110 is connected to a desulfurization apparatus 300.

The desulfurization apparatus 300 removes the sulfur content in the raw material gas supplied from the raw material gas supply means 110 to 0.01 ppm or less, for example.
The desulfurization apparatus 300 includes an upstream desulfurizer 310 and a desulfurizer 320.

For example, the upstream desulfurizer 310 is formed in a substantially cylindrical shape in which a raw material inlet (not shown) is opened at one end in the axial direction and a raw material outlet (not shown) is opened at the other end in the axial direction. .
The upstream side desulfurizer 310 is detachably connected to the raw material inlet side via the joint portion 120 provided with the automatic closing function valve to the raw material gas supply means 110. The joint portion 120 includes a pair of chain portions that can be attached to and detached from each other, and are connected to each other by being connected to each other. In a non-connected state, at least one of the valve bodies such as a ball valve is a biasing member. Various configurations for automatically closing the flow path with the urging force can be used.

The upstream desulfurization vessel is filled with an upstream desulfurization agent. As the upstream desulfurizing agent, for example, a zeolite desulfurizing agent in which at least one kind of metal selected from silver, nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is supported on an inorganic material, nickel, copper, At least one of at least one metal oxide selected from iron, manganese, cobalt, cerium, and lanthanum can be used, and the upstream desulfurization vessel is exchangeably filled.
Here, at least one of desulfurizing agent A and desulfurizing agent B is used as the upstream desulfurizing agent.
The desulfurizing agent A is a desulfurizing agent having, for example, zeolite. Zeolite having a structure of at least one of beta (BEA) and faujasite (FAU) is preferable from the viewpoint of performance. Examples of the zeolite having such a structure include β-type, X-type, and Y-type zeolite, and these may be used alone or in combination of two or more. Further, as the desulfurizing agent A, together with the above-mentioned zeolite, silver (Ag), copper (Cu), nickel (Ni), zinc (Zn), manganese (Mn), iron (Fe), cobalt (Co), alkali metal It is preferable to contain at least one metal component selected from alkaline earth metals and rare earth metals. Here, as an alkali metal, potassium (K), sodium (Na), etc. are mentioned preferably, for example. In addition, preferred examples of the alkaline earth metal include calcium (Cu) and magnesium (Mg). Furthermore, as a rare earth metal, lanthanum (La), cerium (Ce), etc. are mentioned preferably, for example. Among metal components, Ag and Cu are particularly preferable. The desulfurizing agent A can be prepared, for example, by a method in which a metal component is supported on zeolite. Specifically, it is obtained by bringing an aqueous solution containing a water-soluble compound of a target metal into contact with a zeolite by a stirring method, an impregnation method, a flow method or the like, washing with water or the like, and then drying and firing. The upstream desulfurizing agent thus obtained has a metal component content of usually 1 to 40% by mass, preferably 5 to 30% by mass as a metal.
The desulfurizing agent B is at least one selected from at least a metal element, a metal oxide, and a metal component-supported oxide. The desulfurizing agent B is at least one selected from Ag, Cu, Ni, Zn, Mn, Fe, Co, aluminum (Al), silicon (Si), alkali metal, alkaline earth metal, and rare earth metal. Those containing metal components are preferred. Here, as the alkali metal, the alkaline earth metal, and the rare earth metal, the same as the desulfurizing agent A described above is preferably exemplified. And as the desulfurization agent B, what carried each metal component on the porous inorganic oxide support | carrier is preferable, and what carried at least any 1 type in particular among Ag, Cu, and Ni is suitable. Each metal component can be supported by an ordinary method such as a coprecipitation method or an impregnation method. Even with cerium oxide alone, good desulfurization performance can be expressed. Furthermore, you may carry | support at least any 1 type of the said metal component by making cerium oxide into a support | carrier. Examples of the porous inorganic oxide carrier include at least one selected from silica, alumina, silica-alumina, titania, zirconia, zeolite, magnesia, diatomaceous earth, white clay, clay, and zinc oxide. In particular, an alumina carrier and a silica-alumina carrier are preferable.

The desulfurizer 320 includes a desulfurization container and heating means (not shown). This desulfurization vessel has, for example, an opening (not shown) formed at one end in the axial direction, an outflow hole (not shown) formed at the other end in the axial direction, and an internal space filled with a desulfurizing agent. It is formed in a substantially cylindrical shape.
The desulfurizer 320 is connected in series to the upstream desulfurizer 310 via the joint portion 120. Specifically, the inlet is connected to the raw material outlet of the upstream desulfurizer 310 through the joint 120.

The desulfurization vessel is filled with a desulfurization agent. This desulfurizing agent is a stabilized desulfurizing agent containing at least one metal selected from iron, nickel, copper, cobalt, and manganese. In particular, nickel is most preferable. Here, the stabilized stabilizing desulfurization agent containing the above metal is a metal whose surface is oxidized to an oxide, or a metal whose metal is supported on a carrier, or a surface which is supported on the surface of a carrier and whose surface is converted to an oxide. It is an oxidized metal. The stabilizing desulfurizing agent, for example, heats and reduces the metal oxide while flowing a reducing gas such as hydrogen, and after flowing an inert gas such as nitrogen from room temperature to about 100 ° C., the oxygen concentration gradually increases. The oxidation treatment is carried out with increasing the temperature, or it is obtained by exposing it to a carbon dioxide gas stream at room temperature to about 100 ° C. As the carrier, a porous carrier is preferable, and a porous inorganic oxide is particularly preferable. Examples of the porous inorganic oxide include silica, alumina, silica-alumina, titania, zirconia, magnesia, zinc oxide, white clay, clay, diatomaceous earth, and the like. These may be used alone or in combination of two or more. The method for supporting the metal on the carrier is not particularly limited, and any known method such as an impregnation method, a coprecipitation method, or a kneading method can be employed.
And as a nickel type stabilization desulfurization agent which is a preferable desulfurization agent, it can manufacture by the method as shown below, for example. First, an acidic solution containing a nickel source and a basic aqueous solution containing a silicon source are prepared. Here, examples of the nickel source include nickel chloride, nickel nitrate, nickel sulfate, and hydrates thereof. On the other hand, the silicon source is not particularly limited as long as it is soluble in an aqueous alkali solution and becomes silica upon firing, and examples thereof include orthosilicic acid, metasilicic acid, and sodium salts, potassium salts, and water glass thereof. . And the prepared acidic solution and basic aqueous solution are each heated and mixed at about 40 to 80 degreeC, and also hold | maintained at the temperature of about 40 to 80 degreeC, and reaction is completed. Thereafter, the solid matter is sufficiently washed and then separated into solids, or the produced solid matter is separated into solid and liquid and then sufficiently washed, and the solid matter is dried at about 80 ° C. to 150 ° C. by a known method. The obtained dried product is preferably fired at a temperature in the range of 200 ° C. to 400 ° C. to obtain a nickel-supported desulfurization agent. Further, a molding aid is added to the obtained nickel-supported desulfurization agent, granulated to a desired size by a known method such as extrusion molding, rolling granulation, compression molding, and the like, and calcined as necessary. Then, the obtained nickel-based desulfurizing agent is charged into a reactor, heated to 200 ° C. to 500 ° C. in a reducing gas flow such as hydrogen, held for a predetermined time, and then cooled to a temperature of room temperature to about 100 ° C. . Furthermore, switching from a reducing gas to an inert gas such as nitrogen, gradually introducing air to increase the oxygen concentration, holding for a predetermined time, oxidizing treatment, or switching to carbon dioxide gas for nickel-based stabilization A desulfurizing agent is obtained.
The stabilized desulfurizing agent thus obtained preferably has a metal ratio of 50% by mass or more of the total metal amount. Here, when the proportion of the metal is less than 50% by mass, the desulfurization performance may not be sufficiently exhibited. The metal ratio is preferably higher from the viewpoint of desulfurization performance, but in the process of increasing the ratio, metal agglomeration may occur, and it may be difficult to obtain a desired desulfurization agent. What is necessary is just to set suitably in consideration of aggregation and manufacturability.
The metal loading is preferably 30% by mass or more and less than 80% by mass. Here, if the metal loading is less than 30% by mass, the desulfurization performance may not be sufficiently exhibited. On the other hand, when the metal loading is 80% by mass or more, the proportion of the carrier is decreased, and there is a possibility that the mechanical strength and desulfurization performance of the desulfurizing agent are lowered. For this reason, the metal loading is set to 30% by mass or more and less than 80% by mass, preferably 50% by mass or more and less than 80% by mass.
The stabilizing desulfurizing agent is 2 ml to 100 ml per 1 kW of power generation in the fuel cell 200 to be described later, that is, about 1 kW is sufficient as a normal power generation amount in a household fuel cell system. The desulfurization vessel is filled as follows. Here, if the power generation amount is less than 2 ml per 1 kW, there is a possibility that advanced desulfurization treatment cannot be obtained for a long time. On the other hand, when the amount of power generation exceeds 100 ml per 1 kW, the filling space increases, leading to an increase in the size of the apparatus, and even though sufficient desulfurization performance remains, other parts such as a reforming catalyst have a lifetime, May not be economical. For this reason, the stabilizing desulfurizing agent is set to 2 ml or more and 100 ml or less per 1 kW of power generation in the fuel cell 200.

The heating means of the desulfurizer 320 includes, for example, an electric heater such as a sheathed heater spirally disposed on the outer peripheral surface of the desulfurization vessel, and the raw material gas flowing through the inside from the outer surface side of the desulfurization vessel is, for example, 50 ° C. The desulfurization treatment is accelerated by heating at 400 ° C. or lower, preferably 100 ° C. or higher and 300 ° C. or lower. A heat insulating material that covers and heat-insulates the outer surface of the desulfurization vessel is provided on the outer surface of the desulfurizer 320 together with an electric heater. Further, the electric heater is not limited to the spiral arrangement, and may be arranged so as to be folded back along the longitudinal direction of the desulfurization vessel, for example. Furthermore, it is good also as a structure arrange | positioned in the desulfurization container. In addition, exhaust heat from a reformer 410, a CO converter 420, and a CO selective oxidizer 430, which will be described later, is used. Specifically, a pipe for circulating exhaust gas like the heat exchange device 160 is disposed, or a reformer 410, CO converter 420, CO selective oxidizer 430 may be provided with a desulfurizer 320 so that the raw material gas flows through the heat insulating material.
Here, when the temperature during the desulfurization treatment is lower than 50 ° C., the adsorption capacity by the desulfurizing agent is decreased, and the amount of the desulfurizing agent required is increased. Inconveniences such as an increase in the size of the desulfurizer 320 occur, and a highly efficient desulfurization process cannot be obtained. On the other hand, when the temperature is higher than 400 ° C., hydrocarbon coking occurs, which may cause inconveniences such as a desulfurization function being lowered or a pipe being blocked. Thus, the desulfurization treatment is performed at 50 ° C. or higher and 400 ° C. or lower, preferably 100 ° C. or higher and 300 ° C. or lower.

The reforming means 400 is connected to the desulfurizer 320 of the desulfurization apparatus 300 via the steam mixer 140.
The steam mixer 140 mixes steam with the raw material gas after the desulfurization process that flows out from the outlet of the desulfurization vessel in the desulfurizer 320. A heat exchange device 160 is connected to the water vapor mixer 140, and the water vapor supplied from the heat exchange device 160 is mixed with the raw material gas after the desulfurization process flowing out from the desulfurizer 320.

The reforming means 400 reforms the raw material gas mixed with water vapor into a fuel gas as a hydrogen-rich reformed gas.
The reforming unit 400 includes a reformer 410, a CO converter 420, and a CO selective oxidizer 430.

The reformer 410 is filled with a reforming catalyst such as a nickel catalyst (not shown) and includes a burner 411 as a heating device.
The burner 411 is supplied with a raw material gas from a raw material gas supply means 110 that branches on the upstream side of the desulfurization apparatus 300 and with a fuel gas discharged from a fuel cell 200 described later. The burner 411 combusts the raw material gas and the fuel gas with the air supplied from the air supply blower 170, and steam-reforms the raw material gas mixed with water vapor and desulfurized into a hydrogen-rich fuel gas.
High-temperature exhaust gas generated by the combustion of the burner 411 is supplied to the heat exchange device 160, cooled by heat exchange with water, and exhausted into the outside air.
A pure water tank 180 that stores pure water 181 is connected to the heat exchange device 160 via a water supply path 183 having a transport pump 182, and pure water 181 is supplied from the pure water tank 180. The heat exchanging device 160 cools the exhaust gas exhausted from the reformer 410 with the supplied pure water 181 and generates water vapor, and supplies the generated water vapor to the water vapor mixer 140. The pure water tank 180 may store pure water 181 that does not contain impurities such as distilled water, and may have a configuration in which, for example, tap water is purified and supplied as appropriate.

The CO converter 420 is connected in series to the reformer 410 and converts carbon monoxide (CO) contained in the hydrogen-rich fuel gas flowing out from the reformer 410.
The CO selective oxidizer 430 is connected to the CO converter 420 in series, and the CO converter 420 oxidizes CO to carbon dioxide (CO ₂ ) to remove CO in the fuel gas.
Note that the CO converter 420 and the CO selective oxidizer 430 may be integrated with the reformer 410. Furthermore, the steam mixer 140 and the heat exchange device 160 may be integrated. In addition to the CO converter 420 and the CO selective oxidizer 430, a device for adsorbing and removing CO may be provided.
The configuration from the source gas supply means 110 to the reforming means 400 is configured as a fuel gas production apparatus 500 that is a production apparatus for a reformed gas for a fuel cell in the present invention.

The fuel cell 200 is connected to the reforming unit 400, and the fuel gas obtained by the reforming unit 400 is supplied to the fuel cell 200.
The fuel cell 200 reacts hydrogen and oxygen to generate DC power. The fuel cell 200 is, for example, a solid polymer fuel cell, and includes a positive electrode 201, a negative electrode 202, and a polymer electrolyte membrane (not shown) disposed between the positive electrode 201 and the negative electrode 202. For example, air humidified by a humidifier (not shown) is supplied to the positive electrode 201 side, and hydrogen-rich fuel gas humidified via a humidifier (not shown) is supplied to the negative electrode 202 side, for example. Then, hydrogen (fuel gas) and oxygen in the air react to generate water (pure water 181), and DC power is generated between the positive electrode 201 and the negative electrode 202.
The negative electrode 202 side is connected to the burner 411 of the reformer 410 as described above, and the surplus hydrogen content is supplied as fuel for the burner 411. A separator 185 is connected to the positive electrode 201 side. The separator 185 is supplied with air used for the reaction from the positive electrode 201 side, and is separated into air for the gas phase and water (pure water 181) for the liquid phase. The separated air is exhausted to the outside air. The separator 185 is connected to a pure water tank 180 and supplies the separated water (pure water 181) to the pure water tank 180.

The fuel cell 200 is provided with a cooling device 187. The cooling device 187 is provided with a heat recovery device 187A attached to the fuel cell 200. A pure water tank 180 is connected to the heat recovery apparatus 187A via a circulation path 187D including a pump 187B and a heat exchanger 187C.
The circulation path 187D circulates the pure water 181 between the heat recovery device 187A and the pure water tank 180 by driving the pump 187B, thereby cooling the fuel cell 200 that generates heat accompanying power generation and recovering heat.
The heat exchanger 187C exchanges heat with the pure water 181 that has been circulated and recovered heat by the heat recovery device 187A, for example, tap water. The tap water warmed by this heat exchange is directly supplied to other facilities such as a bath for effective use. In addition to heat exchange with tap water, it may be used effectively for other facilities such as generating electricity from heat obtained by heat exchange.

The fuel cell system 100 includes a control device (not shown) that controls the operation of the entire system.
This control device controls the flow rate of the raw material gas, controls the power supplied to the electric heater, which is the heating condition of the heating means of the desulfurizer 320, controls the combustion of the burner 411 of the reformer 410, and generates steam with the heat exchange device 160. For this purpose, supply amount control, temperature management, power generation amount management, and the like of pure water 181 are performed.

[Operation of fuel cell system]
Next, the power generation operation in the fuel cell system 100 described above will be described.

First, a reducing gas such as hydrogen gas is circulated through the desulfurizer 320 at room temperature to 300 ° C. from the joint 120 between the upstream desulfurizer 310 and desulfurizer 320 to reduce the stabilized desulfurizing agent. Keep it. Here, it is preferable to perform the reduction treatment at a relatively high temperature, but it is sufficient to carry out the reduction treatment at room temperature. That is, energy saving can be achieved by performing the reduction treatment at room temperature.
As the circulation of the reducing gas when the stabilized desulfurizing agent is reduced, for example, before connecting the upstream desulfurizer 310, a reducing gas cylinder or the like is connected to the joint unit 120, or the joint unit 120 is circulated. And a configuration in which a reducing gas cylinder can be connected in a state where the upstream desulfurizer 310 such as a three-way valve is connected.

And if a control apparatus acquires the signal regarding a power generation request | requirement, a power generation process will be implemented. That is, source gas and air are supplied to the burner 411 to heat the reformer 410 to about 700 ° C., for example. Further, the control device drives the transport pump 182 to supply the pure water 181 stored in the pure water tank 180 to the heat exchange device 160 via the water supply path 183 to generate water vapor, and the water vapor is supplied to the water vapor mixer 140. Supply. Thereafter, the control device heats the electric heater of the heating means of the desulfurizer 320 to 50 ° C. or more and 400 ° C. or less, preferably 100 ° C. or more and 300 ° C. or less, and removes the source gas from the source gas supply unit 110. To the upstream desulfurizer 310.
The raw material gas supplied to the upstream desulfurizer 310 is desulfurized by an upstream desulfurizing agent at room temperature. Then, the raw material gas desulfurized in the upstream desulfurizer 310 is further flowed into the desulfurizer 320, and the concentration of sulfur is reduced by a desulfurizing agent at a temperature of 50 ° C to 400 ° C, preferably 100 ° C to 300 ° C. Is desulfurized to 0.01 ppm or less. The raw material gas desulfurized by the desulfurization apparatus 300 is mixed with the steam supplied from the heat exchange apparatus 160 by the steam mixer 140 and supplied to the reformer 410 of the reforming means 400. The raw material gas mixed with water vapor is reformed by the reformer 410 into a hydrogen-rich fuel gas. Further, CO in the fuel gas is converted and removed by the CO converter 420 and the CO selective oxidizer 430, and is appropriately humidified by a humidifier or the like, and then supplied to the negative electrode 202 side of the fuel cell 200.
The hydrogen of the fuel gas supplied to the negative electrode 202 side is appropriately humidified by a humidifier or the like and reacts with oxygen in the air supplied to the positive electrode 201 side of the fuel cell 200 to generate water, and the positive electrode 201. DC power is generated between the negative electrode 202 and the negative electrode 202.
The fuel gas containing surplus hydrogen on the negative electrode 202 side is supplied to the burner 411 of the reformer 410 and burned.

[Effects of fuel cell system]
As described above, in the desulfurizer 320 of the desulfurization apparatus 300 of the above embodiment, at least one kind of metal selected from iron, nickel, copper, cobalt, and manganese is extremely low by chemical adsorption at a temperature equal to or higher than normal temperature. Sulfur can be adsorbed and removed at a concentration. For example, a stabilized desulfurization agent in which some of these metal oxides are in a metal state can easily reduce the metal oxide to metal even at room temperature. For this reason, the sulfur content in the raw material gas can be adsorbed and removed highly efficiently by bringing the raw material gas into contact at 50 ° C. or higher and 400 ° C. or lower with the desulfurizing agent obtained by reducing the above-mentioned stabilized desulfurizing agent containing metal. An advanced desulfurization treatment having a concentration of 0.01 ppm or less can be stably obtained for a long period of time, and an efficient operation can be obtained. Furthermore, the minimum necessary desulfurization agent may be used, and the apparatus can be easily downsized.

As the stabilizing desulfurizing agent, a metal whose surface is oxidized to an oxide or a metal covered with CO ₂ is supported on a carrier.
For this reason, handling and manufacture are easy, and also reduction treatment before desulfurization treatment can be facilitated, and an efficient and easy desulfurization treatment can be obtained.

In addition, before the raw material gas is desulfurized, the stabilized desulfurizing agent is reduced at a temperature close to normal temperature.
For this reason, a metal catalyst that can be highly desulfurized can be obtained simply by supplying a reducing gas for reduction such as hydrogen, for example, by reducing hydrogen by introducing hydrogen, and efficient and advanced desulfurization treatment is easy. can get. In addition, since it is a desulfurization process for generating a reformed gas used for power generation in the fuel cell 200, no special process is required even if hydrogen gas is supplied for the reduction of the stabilized desulfurizing agent. By supplying a reducing gas containing hydrogen as a main component, an efficient and advanced desulfurization treatment can be obtained more easily. In particular, the reduction treatment at room temperature eliminates the need for heating, thus saving energy. Even in the case of heating, it is sufficient to use a heating means used in the desulfurization process, and it is not necessary to provide a separate heating means for the reduction treatment, and the configuration can be simplified by sharing the heating means.

Further, an upstream desulfurizer 310 is provided in series on the upstream side of the desulfurizer 320, and after the raw material gas is desulfurized at room temperature by the upstream desulfurizer 310, the desulfurizer 320 performs heat desulfurization treatment.
For this reason, after the sulfur content in the raw material gas is desulfurized to a certain degree at room temperature by the upstream desulfurizer 310, the desulfurization treatment by the desulfurization agent of the desulfurizer 320 that can be highly desulfurized is performed, so the load of the desulfurization agent is reduced. Even with a small amount of desulfurizing agent, a high degree of desulfurization treatment can be stably obtained for a long time.

And, as an upstream desulfurization agent of the upstream desulfurizer 310, a zeolite desulfurization agent in which at least one kind of metal selected from silver, nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is supported on an inorganic material, At least one of at least one metal oxide selected from nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is used.
Therefore, as the upstream desulfurizer 310 that removes a certain amount of sulfur in the raw material gas, at least a zeolite desulfurization agent in which the above-mentioned predetermined metal is supported on an inorganic material, and the above-mentioned metal oxide of the predetermined metal Since either one is used, the upstream desulfurization agent that is relatively easy to manufacture and handle and that can be manufactured at low cost is used, so that more efficient desulfurization treatment can be easily achieved.

Furthermore, the upstream desulfurizer 310 is detachably provided.
For this reason, the configuration for removing a certain amount of sulfur in the raw material gas at room temperature is detachable, that is, replaceable, so that the configuration for performing desulfurization processing at room temperature, which is the previous stage of desulfurization processing, is simple. It can be easily obtained simply by replacing the upstream desulfurizer 310.
In particular, since it is configured to be detachable by the joint part 120 having an automatic closing function, inconvenience due to air flowing into the raw material gas flow path or the desulfurizer 320 at the time of removal can be prevented, and advanced desulfurization treatment can be performed for a longer period of time. Obtained stably.

And, as a stabilizing desulfurizing agent of the desulfurizer 320, 2 ml or more and 100 ml or less are used per 1 kW of power generation in the fuel cell 200 that generates power using the reformed gas generated by the reforming means 400 as a raw material.
For this reason, the required amount of desulfurization agent that can be stably desulfurized stably for a long period of time is sufficient, and the apparatus can be easily downsized.

Furthermore, the present invention is applied to desulfurization of a raw material gas for producing a fuel gas that is a raw material used for power generation in the fuel cell 200.
For this reason, it is particularly useful because it can produce fuel gas stably without generating an increase in size, and can generate power stably even in a configuration that requires high demands such as downsizing and ease of maintenance management for home use. .

[Modification of Embodiment]
The aspect described above shows one aspect of the present invention, and the present invention is not limited to the above-described embodiment, and within the scope of achieving the objects and effects of the present invention. Needless to say, the modifications and improvements are included in the contents of the present invention. In addition, the specific structure and shape in carrying out the present invention may be used as other structures and shapes within the scope of achieving the object and effect of the present invention.

In other words, as described above, the desulfurization apparatus of the present invention has been described in the form of configuring the fuel cell system 100. For example, the desulfurization apparatus is applied to the fuel gas production apparatus 500 for supplying the fuel cell 200 with hydrogen-rich fuel gas. You may do it. Furthermore, although the desulfurization apparatus 300 is configured by the upstream desulfurizer 310 and the desulfurizer 320, it can be used as the desulfurizer 320.
Moreover, a plurality of serial upstream desulfurizer 310 and desulfurizer 320 configurations may be provided, or a plurality of upstream desulfurizers 310 may be provided upstream of desulfurizer 320. Furthermore, when providing the several upstream desulfurizer 310, it should just be in series with respect to the desulfurizer 320, and upstream desulfurizer 310 may be connected in parallel.

The shape of the desulfurization container of the desulfurizer 320 is not limited to a cylindrical shape. For example, it may be a cylindrical shape such as an elliptical cross section or a polygonal cross section. In particular, when the system is configured as a unit configured to be housed in the case, it can be arranged at the corner of the case by using a triangular tube shape, and the entire unit can be reduced in size.
Furthermore, it is good also as a structure bent so that an axial direction may meander somewhat depending on arrangement | positioning relationship of another apparatus, components, etc.
Similarly, the container shape of the upstream desulfurizer 310 can be appropriately designed.

Further, as described above, the heating means of the desulfurizer 320 is not limited to the configuration in which the heater is heated from the outside of the desulfurization vessel, and may be disposed in the desulfurization vessel, for example. Moreover, not only electric heaters, such as a sheathed heater, but various heaters can be used. Furthermore, the heat of combustion gas such as a burner may be used, or the exhaust heat of the reforming means 400 may be used.
The electric heater has been described as being spirally disposed outside the desulfurization vessel, but may be disposed so as to be folded back along the longitudinal direction of the desulfurization vessel, for example.

In addition, as a stabilizing desulfurization agent of the desulfurizer 320, the reduction treatment has been described before the desulfurization treatment of the raw material gas, but the reduction treatment may not be performed.
Moreover, although the upstream desulfurizer 310 has been described as being desulfurized at room temperature, it may be heated by providing a heating means. Furthermore, it may be an installation type instead of a detachable configuration. And as a structure which can be attached or detached, not only the structure using the joint part 120 which has the automatic closing function mentioned above but the structure connected variously can be used.

Further, as the source gas supply means 110, for example, as shown in FIG. 2, a source tank 11 that also functions as a vaporizer that stores or fills the source gas 10 such as LPG may be detachable.
That is, as shown in FIG. 2, the raw material gas supply means 110 is branched by providing a multi-way valve, for example, a three-way valve 113, on the upstream side of the raw material supply pipe 112 provided with the flow meter 111. The upstream end of the branched material supply pipe 112 functions as a flexible connecting pipe 112A, and the tip of the connecting pipe 112A has the same automatic function as the joint 120 of the upstream desulfurizer 310. The raw material tank joint part 114 provided with the closing function valve is provided, and the raw material tank 11 can be attached or detached.
The three-way valve 113 automatically switches according to the supply pressure of the raw material gas 10 supplied from the connected raw material tank 11 in addition to a configuration that appropriately switches the upstream communication state of the raw material supply pipe 112 that branches manually. Various switching valves, such as a switching structure, can be used. Furthermore, the raw material gas supply means 110 is not limited to the configuration using the three-way valve 113 and is branched into three or more branches by combining three or more raw material tanks 11 and appropriately switching a multi-way valve or a plurality of three-way valves 113. It is good also as a structure.
As described above, the raw material tank 11 is detachably connected by the connecting pipe 112A having the raw material tank joint portion 114 provided with the automatic closing function valve, so that when the raw material tank 11 is removed, the air is supplied to the raw material gas 10. Inconvenience due to flow into the desulfurizer 320 and flow into the desulfurizer 320, that is, desulfurization activity that is reduced by deoxidizing the desulfurization agent that has been reduced by stabilizing the desulfurization agent is reduced with a simple configuration. Therefore, a good desulfurization treatment can be easily obtained. Furthermore, since the raw material tank 11 that is easily replenished with the raw material gas 10 and is widely used is used, for example, it can also be used as the supply of the raw material gas 10 in the household fuel cell system 100, and the use can be easily expanded. At the same time, replenishment and supply of the source gas can be easily performed, and stable supply of the reformed gas can be easily obtained.
In addition, although the raw material tank joint part 114 provided with the automatic closing function valve was provided at the end of the connecting pipe 112A to which the raw material tank 11 is detachably connected, for example, the raw material tank 11 is detachably connected. The end portion of the connecting pipe 112A may be connected by ordinary screwing or the like, and an automatic sealing function valve may be provided at an intermediate portion of the connecting pipe 112A, preferably at the tip end side.

Furthermore, in order to prevent the desulfurization agent obtained by reducing the stabilized desulfurization agent in the desulfurizer 320 from being oxidized, a deoxygenation means 330 may be provided as shown in FIG. 3, for example.
That is, as shown in FIG. 3, a deoxygenation container filled with a deoxidizer that removes oxygen in the air flowing into the flow path of the raw material gas 10 upstream of the desulfurizer 320, particularly immediately before the desulfurizer 320. As with the upstream desulfurizer 310, the deoxidation joint portion 331 having an automatic closing function valve is detachably connected.
Thus, for example, when the raw material tank 11 is attached / detached, air flows into the flow path of the raw material gas 10, or when the cylinder for supplying the reducing gas for reducing the stabilized desulfurizing agent in the desulfurizer 320 is attached / detached. Even if air flows in, oxygen can be prevented from flowing into the desulfurizer 320, inconvenience due to the inflow of air, that is, oxygen can be prevented, and stable and good desulfurization treatment can be easily obtained.
As the oxygen scavenger, for example, various oxygen scavengers such as iron particles that adsorb oxygen can be used. Furthermore, the present invention is not limited to a configuration using an oxygen scavenger, and various devices that remove oxygen by reaction, for example, can be used. The deoxygenating means 330 may be a stationary type instead of a detachable configuration. And as a structure which can be attached or detached, not only the structure using the deoxidation joint part 331 which has the automatic closing function mentioned above but the structure connected variously can be used.

  In addition, the specific structure and shape in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

Next, the present invention will be described more specifically with reference to examples and comparative examples.
In addition, this invention is not limited to the content of an Example etc. at all.

(Preparation of desulfurization agent)
Heat nickel sulfate hexahydrate (Wako Pure Chemical Industries, Ltd., special grade) 730.2 g and copper sulfate pentahydrate (Wako Pure Chemical Industries, Ltd., special grade) 151.3 g to 80 ° C. Dissolve in 8 L of the prepared water to prepare a nickel-based aqueous solution. This nickel-based aqueous solution and pseudo boehmite (manufactured by Catalyst Kasei Kogyo Co., Ltd., trade name: C-AP (containing 67% by mass as Al ₂ O ₃ )) 16.0 g are mixed, and 0.5 mol / L sulfuric acid is mixed. 300 ml of an aqueous solution (manufactured by Wako Pure Chemical Industries, Ltd., special grade) was added to prepare a preparation solution A at pH2.
Moreover, 600.0 g of sodium carbonate (made by Wako Pure Chemical Industries, Ltd., special grade) was dissolved in 8 L of water heated to 80 ° C., and water glass (made by Nippon Chemical Industry Co., Ltd., trade name: J-1 (Si concentration 29) Preparation liquid B was prepared by adding 180.2 g of mass%)).
Preparation liquid A and preparation liquid B were mixed while being kept at 80 ° C., respectively, and stirred for 1 hour. Thereafter, the precipitated cake was washed with 60 L of water and then collected by filtration, followed by drying at 120 ° C. for 12 hours with an air dryer (trade name: SPH-200, manufactured by ESPEC CORP.). Furthermore, the dried product was calcined at 350 ° C. for 3 hours using a calcining furnace (manufactured by Advantech Toyo Co., Ltd., trade name: FUW234PA) to obtain a Ni—Cu catalyst containing 65% by mass of Ni and 15% by mass of Cu. This Ni-Cu catalyst was compression molded to obtain a non-stabilized desulfurization agent with a uniform particle size of 16-32 mesh.
The reactor was charged with 15 ml of this non-stabilized desulfurization agent, and gradually heated from room temperature to 350 ° C. while supplying hydrogen at 1 L / min. After reaching 350 ° C., it was maintained for 3 hours. Thereafter, the supply of hydrogen was stopped, and the mixture was naturally cooled to room temperature while supplying nitrogen gas at 1 L / min. Furthermore, air was supplied so that the oxygen concentration would be 2% and maintained for 50 hours to prepare a stabilized desulfurization agent.

(Desulfurization evaluation experiment; without hydrogen reduction)
As Example 1, 1 ml of the stabilized desulfurizing agent prepared above was sampled and filled into a reaction tube having an inner diameter of 10 mm. And desulfurized propane (manufactured by Takachiho Chemical Industries), dimethyl sulfide (1000 volppm) / tertiary butyl mercaptan (1000 volppm) / nitrogen balance cylinder (manufactured by Takachiho Chemical Industries), carbonyl sulfide (300 volppm) / nitrogen balance Cylinder (manufactured by Takachiho Chemical Co., Ltd.) is mixed so that the total sulfur content is 17 ppm by volume ((dimethyl sulfide / tertiary butyl mercaptan / COS) (2/2/1) by volume ratio). In a state where the amount was 166 ml / min, the reaction tube was supplied at normal pressure and 180 ° C.
The gas at the outlet of the reaction tube was analyzed in a timely manner by gas chromatography equipped with a chemiluminescent sulfur detector.
In Comparative Example 1, 1 ml of an unstabilized desulfurizing agent prepared at the time of preparing the stabilized desulfurizing agent was used in the reaction tube instead of the stabilized desulfurizing agent.
As a result, when the non-stabilized desulfurizing agent as Comparative Example 1 was used, the time required for the sulfur concentration of the gas flowing out from the reaction tube to reach 1 ppm by volume was 27 hours. On the other hand, in the case where the stabilized desulfurizing agent of Example 1 was used, it was 52 hours. For this reason, it has been found that a high degree of desulfurization treatment can be obtained up to approximately double the time by heat desulfurization treatment using a stabilizing desulfurization agent.

(Desulfurization evaluation experiment; with hydrogen reduction)
As Example 2, 1 ml of the stabilized desulfurizing agent prepared above was sampled and filled into a reaction tube having an inner diameter of 10 mm. And hydrogen gas was distribute | circulated for 3 minutes at 20 degreeC and the supply rate of 100 ml / min under normal pressure, and the hydrogen reduction process was carried out. Thereafter, gas was supplied to the reaction tube in the same manner as the desulfurization evaluation experiment described above.
In Comparative Example 2, 1 ml of an unstabilized desulfurizing agent prepared at the time of preparing the stabilized desulfurizing agent was used in the reaction tube instead of the stabilized desulfurizing agent.
As a result, in the case of using the non-stabilized desulfurization agent which is Comparative Example 2, the time until the sulfur concentration of the gas flowing out from the reaction tube reaches 1 ppm by volume is 30 hours, and about 10% by hydrogen reduction. An extension of the life was recognized. On the other hand, in the case where the stabilized desulfurizing agent of Example 2 was used, a life extension of about 1.6 times was recognized in 85 hours. As described above, it has been found that by performing the desulfurization treatment after reducing the stabilized desulfurizing agent, a further long-term advanced desulfurization treatment can be obtained.

(Parallel upstream desulfurizer)
200 g of a 500 ° C. sintered product of β-type zeolite (product of Tosoh Corporation, trade name: HSZ-930NHA) is added to an aqueous solution in which 64 g of silver nitrate (made by Wako Pure Chemical Industries, Ltd., special grade) is dissolved in 100 ml of water, and stirred for 4 hours. Then, ion exchange was performed. Thereafter, the solid was washed with 20 L of water and then collected by filtration, followed by drying at 120 ° C. for 12 hours with an air dryer (trade name: SPH-200, manufactured by ESPEC Corporation). Furthermore, the dried product was calcined at 400 ° C. for 3 hours using a calcining furnace (manufactured by Advantech Toyo Co., Ltd., trade name: FUW234PA) to obtain an Ag catalyst containing 12.5% by mass of Ag. This Ag catalyst was compression molded, and the particle size was made uniform in 16-32 mesh to obtain an upstream desulfurization agent.
Further, 20 ml of the stabilized desulfurizing agent prepared above was filled in a reaction tube having an inner diameter of 0.8 cm.
Then, 270 ml of the upstream desulfurizing agent prepared above was charged into an upstream reactor having an inner diameter of 40 mm, and 120 ml of non-stabilized desulfurizing agent prepared at the time of preparing the stabilized desulfurizing agent was further charged. In addition, in a 1 kW class LPG fuel cell system charged with 500 g of the reforming catalyst, a reactor tube filled with the above-mentioned stabilized desulfurizing agent is placed at a position where the upstream reactor is 40 to 55 ° C. during normal operation. Each was incorporated at a position where the temperature was from ℃ to 190 ℃.
Further, hydrogen reduction treatment was performed by flowing hydrogen at a supply rate of 300 ml / min for 20 minutes under a normal pressure from a joint portion with an automatic closing mechanism provided on the downstream side of the upstream reactor. The LPG in the 1 kW class LPG fuel cell system was supplied by using a 50 kg cylinder while appropriately switching by an automatic switching method.
As a result, when 4000 hours passed after the start of operation of the fuel cell system, the outlet sulfur concentration of the upstream reactor was analyzed at the timing when the LPG cylinder was automatically switched, and as a result, it was 7 mass ppb. In addition, as a measuring method of sulfur concentration, based on ASTM D 6313 Difference Photometry method, it quantified using the XVI apparatus of ONIX.
In addition, after the operation was stopped, the reformer was disassembled, and sulfur analysis of the reforming catalyst was performed by fluorescent X-ray analysis. The detection limit was 2.5 mass ppm or less, which was converted from the gas flow rate. The average sulfur concentration at the outlet of the reactor was 1.3 mass ppb or less. Thus, it was found that by arranging the upstream desulfurizers in parallel, a more advanced desulfurization treatment can be stably obtained even for a long period of 4000 hours.

(High temperature reduction)
1 ml of the stabilized desulfurizing agent prepared above was sampled and filled into a reaction tube having an inner diameter of 10 mm.
Then, while allowing hydrogen gas to flow through the reaction tube at a supply rate of 100 ml / min under normal pressure, the temperature of the reaction tube is gradually raised from room temperature to 200 ° C., and after reaching 200 ° C., the reaction tube is held for 2 hours to reduce hydrogen Processing was carried out. Thereafter, gas was supplied to the reaction tube in the same manner as the desulfurization evaluation experiment described above. The gas at the outlet of the reaction tube was analyzed in a timely manner by gas chromatography equipped with a chemiluminescent sulfur detector.
As a result, the time required for the sulfur concentration of the gas flowing out of the reaction tube to reach 1 ppm by volume was 140 hours, which further extended the life.

  The present invention relates to liquefied natural gas mainly composed of methanol and methane, city gas mainly composed of this natural gas, synthetic liquid fuel using natural gas as a raw material, liquefied petroleum gas (LPG), dimethyl ether, naphtha, kerosene. It can be used for the desulfurization treatment of raw material gas containing petroleum hydrocarbons. In particular, it can be used for a desulfurization apparatus in a fuel cell system.

1 is a block diagram showing a schematic configuration of a fuel cell system according to an embodiment of the present invention. It is a block diagram which shows schematic structure of the raw material gas supply means in the fuel cell system which concerns on other embodiment of this invention. It is a block diagram which shows schematic structure of the fuel cell system which concerns on further another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Raw material gas 11 ... Raw material tank 100 ... Fuel cell system 110 ... Raw material gas supply means 114 ... Raw material tank joint part which is a joint part 120 ... Joint part 200 ... Fuel cell 300 ... Desulfurization apparatus 310 …… Upstream side desulfurizer 330 …… Deoxygenation means 331 …… Deoxygenation joint part 320 which is a joint part 320 ...... Desulfurizer 410 ...... Reformer 500 …… Fuel gas as a production apparatus for reformed gas for fuel cells Manufacturing equipment

Claims (21)

A desulfurization method for desulfurizing a raw material gas containing a hydrocarbon raw material with a desulfurization agent,
The desulfurized raw material gas is heated under a reforming catalyst and connected in series to the upstream side where the raw material gas flows in a reformer that generates a reformed gas containing hydrogen gas, iron, nickel, Using a desulfurizer filled with the stabilized desulfurization agent that is partly in a metal state with at least one selected from copper, cobalt, and manganese,
A desulfurization method, wherein the raw material gas is desulfurized at 50 ° C. or higher and 400 ° C. or lower with the desulfurizing agent. The desulfurization method according to claim 1,
The desulfurization method, wherein the stabilized desulfurizing agent is at least one of a metal whose surface is oxidized to an oxide and a metal treated with carbon dioxide. The desulfurization method according to claim 1 or 2,
The desulfurization method, wherein the stabilized desulfurizing agent is reduced in a temperature range of normal temperature to 300 ° C. before desulfurization of the raw material gas. The desulfurization method according to claim 1 or 2,
The desulfurization method, wherein the stabilized desulfurizing agent is reduced at normal temperature before the desulfurization treatment of the raw material gas. A desulfurization method according to any one of claims 1 to 4,
The desulfurizer is characterized in that the raw material gas is desulfurized by using an upstream desulfurizer that desulfurizes the raw material gas at room temperature. The desulfurization method according to claim 5,
The upstream desulfurizer includes a zeolite desulfurization agent in which at least one kind of metal selected from silver, nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is supported on an inorganic material, and nickel, copper, iron, manganese And at least one of at least one metal oxide selected from cobalt, cerium, and lanthanum. The desulfurization method according to claim 5 or 6,
The upstream desulfurizer is detachably disposed in the flow path of the raw material gas. A desulfurization method according to any one of claims 1 to 7,
The desulfurizer is configured to desulfurize the raw material gas from which oxygen has been removed by using a deoxygenating means for removing oxygen mixed in the raw material gas that is distributed. A desulfurization method according to any one of claims 1 to 8,
The desulfurizer is filled with the stabilized desulfurizing agent at a rate of 2 ml to 100 ml per 1 kW of power generation in a fuel cell that generates electricity using the reformed gas generated by the reformer as a raw material. Method. A desulfurization apparatus in which a desulfurizing agent for desulfurizing a raw material gas containing a hydrocarbon raw material is filled,
An accommodation space filled with a stabilized desulfurization agent containing at least one metal selected from iron, nickel, copper, cobalt, and manganese is contained therein, and an inflow port into which the raw material gas flows and in the accommodation space An upstream side into which the raw material gas flows in a reformer that includes an outlet through which the raw material gas flows out and heats the desulfurized raw material gas under a reforming catalyst to generate a reformed gas containing hydrogen gas Containers connected in series to
Heating means for heating the inflowing source gas to 50 ° C. or more and 400 ° C. or less and desulfurizing with the desulfurizing agent;
A desulfurization apparatus characterized by comprising: It is a desulfurization apparatus of Claim 10, Comprising:
The desulfurization apparatus, wherein the stabilized desulfurizing agent is a metal whose surface is oxidized to an oxide. The desulfurization apparatus according to claim 10 or 11,
A desulfurization apparatus comprising a reducing means for supplying the reducing gas into the container to reduce the desulfurizing agent in a temperature range of normal temperature to 300 ° C. A desulfurization apparatus according to any one of claims 10 to 12,
An upstream desulfurizer connected in series to the desulfurizer on the upstream side in which the raw material gas flows in the desulfurizer and filled with an upstream desulfurizing agent that desulfurizes the raw material gas at room temperature; This is a desulfurization equipment. The desulfurization apparatus according to claim 13,
The upstream desulfurization agent includes a zeolite desulfurization agent in which at least one kind of metal selected from silver, nickel, copper, iron, manganese, cobalt, cerium, and lanthanum is supported on an inorganic material, and nickel, copper, iron, manganese A desulfurization apparatus, wherein the desulfurization apparatus is at least one of at least one of metal oxides selected from cobalt, cerium, and lanthanum. The desulfurization apparatus according to claim 13 or 14,
The upstream desulfurizer includes a joint portion having an automatic closing function that is detachably disposed in the flow path of the raw material gas. A desulfurization apparatus according to any one of claims 10 to 15,
A desulfurization apparatus comprising a deoxygenation means connected in series with the desulfurizer on the upstream side of the raw material gas in the desulfurizer to remove oxygen mixed in the raw material gas flowing. . The desulfurization apparatus according to claim 16, wherein
The deoxygenation device includes a joint portion having an automatic closing function that is detachably disposed in the flow path of the source gas. A desulfurization apparatus according to any one of claims 10 to 17,
The desulfurizer is filled with the stabilized desulfurization agent at a rate of 2 ml to 100 ml per 1 kW of power generation in a fuel cell that generates electricity using the reformed gas generated by the reformer as a raw material. . A raw material gas supply means for supplying a raw material gas containing a hydrocarbon raw material;
The desulfurization apparatus according to any one of claims 10 to 18, wherein the raw material gas supplied from the raw material gas supply means is subjected to a desulfurization treatment.
A reformer charged with a reforming catalyst for reforming the reformed gas containing hydrogen gas by heating the raw material gas desulfurized by the desulfurization apparatus;
An apparatus for producing a reformed gas for a fuel cell, comprising: An apparatus for producing a reformed gas for a fuel cell according to claim 19,
The apparatus for producing a reformed gas for a fuel cell, wherein the source gas supply means includes a joint portion having an automatic sealing function to which a source tank for storing source gas is detachably connected. An apparatus for producing a reformed gas for a fuel cell according to claim 19 or 20,
An oxygen-containing gas supply means for supplying an oxygen-containing gas;
A fuel cell that generates power using the reformed gas reformed by the reformer of the reformed gas fuel gas production apparatus and the oxygen-containing gas supplied by the oxygen-containing gas supply means;
A fuel cell system comprising:

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