JP2001279256A - Desulfurization device for fuel battery and method for operating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a desulfurization device which is used for a fuel battery, can desulfurize a raw material oil, such as kerosene, down to a sulfur content of <=0.1 wt.ppm over a long time, and facilitates the exchange of a desulfurizer, when the performance of the desulfurizer is lowered, and to provide a method for operating the desulfurization device. SOLUTION: This desulfurization device for a fuel battery is characterized by having a tank 1 for a raw material oil, a raw material oil pre-heater 2 for heating the raw material oil supplied from the tank 1 for the raw material oil, a desulfurizer 3 for desulfurizing the raw material oil heated with the raw material oil pre-heater 2, and an evaporator 4 for evaporating the raw material oil desulfurized with the desulfurizer to supply the evaporated raw material oil to a reformer, as main components, and the method for operating the desulfurization device is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desulfurization apparatus for a fuel cell and a method for operating the same. More specifically, the present invention relates to a method in which a feed oil such as
The present invention relates to a desulfurization apparatus for a fuel cell which can be desulfurized to a weight ppm or less and whose desulfurizing agent deteriorates in performance, in which the desulfurizing agent or desulfurizer can be easily replaced, and a method for operating the desulfurizing apparatus.

[0002]

2. Description of the Related Art In recent years, new energy technologies have been spotlighted due to environmental problems, and fuel cells have attracted 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 the feature of high energy use efficiency.
Practical research is being actively conducted for industrial or automotive use. As the fuel cell, types 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,
Hydrogen sources include liquefied natural gas mainly composed of methanol and methane, city gas mainly composed of natural gas, synthetic liquid fuel derived from natural gas, and hydrocarbon oils such as petroleum naphtha and kerosene. The use of has been studied.

When a fuel cell is used for consumer or automobile use, the petroleum hydrocarbon oil, especially kerosene, is liquid at normal temperature and normal pressure, is easy to store and handle, and has a gas station or a store. It is advantageous as a hydrogen source because the supply system is in place. However,
Petroleum hydrocarbon oils have a problem that they have a higher sulfur content than methanol and natural gas oils. When hydrogen is produced using this petroleum-based hydrocarbon oil, a method is generally used in which the hydrocarbon oil is subjected to steam reforming or partial oxidation reforming treatment in the presence of a reforming catalyst. In such a reforming treatment, the reforming catalyst is poisoned by the sulfur content in the hydrocarbon oil.Therefore, from the viewpoint of the life of the catalyst, the hydrocarbon oil is subjected to a desulfurization treatment to reduce the sulfur content. Usually 0.2
It is important to keep the weight ppm or less, preferably 0.1 ppm by weight or less. Many studies have been made on the desulfurization method of petroleum hydrocarbon oils.
-Using a hydrodesulfurization catalyst such as Mo / alumina or Ni-Mo / alumina and a hydrogen sulfide adsorbent such as ZnO,
A method of hydrodesulfurization at a pressure of 5 MPa and a temperature of 200 to 400 ° C. is known. This method is a method of performing hydrodesulfurization under severe conditions to remove the sulfur content into hydrogen sulfide, and it is difficult to reduce the sulfur content to 0.2 ppm by weight or less. Hard to apply to hydrogen oil.

On the other hand, a nickel-based adsorbent is used as a desulfurizing agent capable of adsorbing and removing sulfur content in hydrocarbon oil under mild conditions without hydrorefining treatment to reduce the sulfur content to 0.2 ppm by weight or less. (Japanese Patent Publication No. 6-65602)
No. 7-115842, No. 7-115
No. 843, Japanese Patent No. 2591971, Japanese Patent Publication No. 2-2
Nos. 75701, 2-204301, 5-70780, 6-80972, 6-91173, and 6-228570). These nickel-based adsorbents are advantageous for application as a desulfurizing agent to hydrocarbon oils for fuel cells,
In any of the publications, there is no description about a desulfurization apparatus which can desulfurize to a low level for a long time and has a detachable desulfurizer as needed.

[0005]

Under such circumstances, the present invention can desulfurize a raw oil such as kerosene to a sulfur content of 0.1 ppm by weight or less for a long time, and the desulfurizing agent can be used. It is an object of the present invention to provide a desulfurization device for a fuel cell in which the desulfurizing agent or the desulfurizer can be easily replaced when the performance is deteriorated, and an operation method of the desulfurization device.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, have found that a stock oil tank, a stock oil preheater, a desulfurizer, and preferably a detachable cartridge type desulfurizer. That the main component of the reactor and the vaporizer can be used as a desulfurization device for fuel cells, and by using this device, the desulfurization process supplied to the reformer for hydrogen production It has been found that the vaporized gas of the feed oil can be obtained efficiently. The present invention has been completed based on such findings. That is, the present invention
A feedstock tank, a feedstock preheater for heating the feedstock supplied from the feedstock tank, a desulfurizer for desulfurizing the feedstock heated by the feedstock preheater, and a desulfurization process for the desulfurizer A desulfurization device for a fuel cell, comprising a vaporizer as a main component, which vaporizes a feed oil and supplies it to a reformer,
Particularly preferably, the present invention provides a desulfurizer for a fuel cell, wherein the desulfurizer is a detachable cartridge type. The present invention also provides a method for operating a desulfurization device for a fuel cell, comprising using the above desulfurization device, desulfurizing a raw oil, vaporizing the oil, and supplying it to a reformer.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a fuel cell desulfurization apparatus according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram of an example of a desulfurization apparatus for a fuel cell according to the present invention. As shown in this figure, the desulfurization apparatus according to the present invention includes a feedstock tank 1, a feedstock preheater 2, and a desulfurizer. 3 and a carburetor 4 as main components. The base oil in the base oil tank 1 is supplied to the base oil preheater 2 by the base oil supply pump 6. In this case, a charging tank 5 can be provided between the base oil tank 1 and the base oil supply pump 6 to stabilize the flow of the base oil. In addition, when the pressure of the raw oil in the tank 1 is sufficiently high due to a high position of the raw oil tank 1 or the like, the raw oil can be supplied without installing the raw oil supply pump 6.

The feed oil supplied to the feed oil preheater 2 is guided by the desulfurizer 3 after being heated by the preheater 2.
The heating mechanism 7 in the feedstock preheater 2 is not particularly limited, and includes, for example, an electric heater or a heating mechanism by heat exchange with a heated gas or a liquid heat medium. It is industrially advantageous to use the hot exhaust gas discharged from the furnace of the plaster. In this case, when a later-described vaporizer 4 is first heated with this heat, and the relatively low-temperature exhaust gas is used as a heat source of the feedstock preheater, the efficiency of heat utilization of the entire fuel cell system increases, preferable. The desulfurizer 3 is filled with a desulfurizing agent described in detail later. This desulfurizer 3
Is preferably a detachable cartridge type, for which two valves 8, 8 'and 9, 9' are provided at the inlet and outlet of the desulfurizer 3, respectively. Are provided with mounting portions 10 and 11, respectively. When replacing the desulfurizing agent and the desulfurizer, each valve can be closed, and the desulfurizer 3 can be cut off at the mounting portions 10 and 11. When installing the desulfurizer 3, the reverse operation may be performed.

When the length of the desulfurizing agent-filled layer is L and the diameter of the desulfurizing agent-filled layer is D, the desulfurizer 3 usually has an L / D value of 8
The number is preferably 10 or more. If the L / D value is less than 8, it becomes difficult to desulfurize the raw oil to a desired low level. D is a length obtained by converting the cross-sectional area of the packed bed into a diameter. When the L / D value is large as described above, the desulfurizer may be bent in the middle and formed into a U-shape or a folded shape that is folded several times, or a jacket, from a viewpoint of downsizing the device, rather than forming a straight pipe. It is advantageous to mold. FIGS. 2A and 2B are perspective views showing different examples of the shape of a desulfurizer used in the desulfurization apparatus of the present invention, wherein FIGS.
(C) is a folded type, (d) and (e) are jacket types (double tube type).

[0010] The material of the desulfurizer is not particularly limited, and metals and plastics can be used.
When using at a high temperature, it is necessary to consider heat resistance. In the case of external heating, it is preferable to use a metal having good heat conductivity. Specifically, stainless steel, carbon steel, or the like is used. Further, when the desulfurizer is made of metal, a treatment is usually taken to cover the periphery of the desulfurizer with a heat insulating material. In FIG. 1, the desulfurization-treated raw material oil discharged from the desulfurizer 3 is supplied to the vaporizer 4 as it is or once stored in a tank (not shown). The desulfurization-treated feedstock vaporized in the vaporizer 4 is supplied to a reformer (not shown) for hydrogen production. The structure of the vaporizer 4 is not particularly limited, and for example, a method of vaporizing in a heated pipe, a method of vaporizing in a heated container, a method of directly blowing into a heated medium, and the like can be considered. In addition, since the heat transfer efficiency of the pipeline or the container is unfavorably reduced if unevaporated components remain, an oil reservoir or the like is provided at the outlet of the vaporizer, and the unevaporated oil is returned to the original feedstock oil tank or the like therefrom. A mechanism may be provided.

The heating mechanism 12 of the vaporizer 4 is not particularly limited, and includes, for example, an electric heater, a dedicated burner, or a heating mechanism for exchanging heat with a heated gas or a liquid heat medium. It is industrially advantageous to use high-temperature exhaust gas discharged from a furnace of a reformer installed in a fuel cell. Since the temperature of the exhaust gas is usually as high as 600 to 800 ° C., if the heat is exchanged as it is, the temperature inside the vaporization becomes too high, and the feed oil may be carbonized in the vaporizer. In this case, it is preferable to use the exhaust gas by separately lowering the temperature of the exhaust gas to 650 ° C. or lower. The means for exchanging heat with the high-temperature exhaust gas in the vaporizer is not particularly limited. For example, exhaust gas may be introduced into a container, and a kerosene pipe may be introduced into the exhaust gas. In this case, in order to increase the heat transfer area, the pipe in the container through which the exhaust gas flows may be formed in a coil shape.
As another example, high-temperature exhaust gas may be allowed to pass around a pipe or a container through which kerosene flows. Furthermore, in this vaporizer, a container or a tube can be filled with a filler. As a result, it is possible to improve heat transfer and prevent local heating, to make the apparatus compact, improve load followability, and prevent carbonization of kerosene in a tube furnace. Examples of the filler include heat-resistant fibers such as ceramic balls and silica wool, and heat-resistant materials having good heat conductivity such as silicon carbide. The form of the filler is not particularly limited, and may be any of fibrous, molded, porous, sponge, and the like.

When vaporizing in a heated container,
In order to increase the vaporization efficiency, a mechanism capable of spraying the raw oil into the vaporizer may be provided. In this case, the size of the oil droplet is 5
The diameter is preferably not less than μm. The diameter of this oil droplet is 5μ
If it is less than m, oil droplets will float on the heating surface inside the vaporizer, which may lower the vaporization efficiency. In addition,
When a storage tank is provided downstream of the desulfurizer 3 and the desulfurization-processed raw material oil is supplied to the vaporizer 4, a raw-oil feed pump is installed in the storage tank. Next, an operation method of the desulfurization device for a fuel cell according to the present invention will be described. In the method of the present invention, the above-mentioned desulfurization apparatus for a fuel cell is used to desulfurize a raw material oil, and then vaporize and supply it to a reformer for hydrogen production.

In this case, petroleum-based gasoline, naphtha, kerosene, light oil, and the like, which are liquid at normal temperature and pressure, are used as the feedstock oil. Among them, kerosene is preferable, and particularly, the sulfur content is 80%. JIS No. 1 kerosene having a weight of not more than ppm is preferred. This JIS No. 1 kerosene is obtained by desulfurizing crude kerosene obtained by distilling crude oil at normal pressure. The crude kerosene is
Usually, the sulfur content is large, and it does not become JIS No. 1 kerosene as it is, and it is necessary to reduce the sulfur content. As a method of reducing the sulfur content, desulfurization treatment is preferably performed by a hydrorefining method that is generally carried out industrially. in this case,
As the desulfurization catalyst, a mixture of transition metals such as nickel, cobalt, molybdenum, and tungsten in an appropriate ratio, which is supported on a carrier mainly composed of alumina in the form of a metal, oxide, or sulfide is used. Can be The reaction conditions are, for example, a reaction temperature of 250 to 400 ° C. and a pressure of 2-1.
Conditions such as 0 MPa · G, a hydrogen / oil molar ratio of 2 to 10, and a liquid hourly space velocity (LHSV) of ^{1 to 5} h ⁻¹ are used.

As the desulfurizing agent to be charged into the desulfurizer 3, an arbitrary one can be appropriately selected from those conventionally known as desulfurizing agents for hydrocarbon oils. In particular,
Carbon materials such as activated carbon and activated carbon fiber; silicon oxides such as silica gel and hydrophobic silica; zeolites such as zeolite and metal-exchanged zeolite; oxides, sulfite hydrates or hydroxides of alkali metals and alkaline earth metals A carrier carrying an alkali metal or an alkaline earth metal;
Oxides of metals such as lead, tin, iron, nickel, cobalt, manganese, chromium, copper, zinc, and mixtures or composite oxides thereof; lead, tin, iron, nickel, cobalt, manganese, chromium, copper, zinc, etc. Supported on a carrier alone or in combination of two or more, and further added with an alkali metal, an alkaline earth metal, a rare earth metal (Ce, La, Y, etc.); noble metals such as platinum, palladium, rhodium, ruthenium Supported on a carrier.

As the above carrier, for example, silica, alumina, silica-alumina, titania, zirconia, zinc oxide, terra alba, diatomaceous earth, clays and the like can be used. Of the various desulfurizing agents described above, if lead, tin, iron, nickel, cobalt, copper, precious metal, etc. are used in advance, if they are subjected to a reduction treatment, desulfurization to a lower level is possible. When the kerosene is used as a feed oil, a nickel-based desulfurizing agent is particularly suitable. As the nickel-based desulfurizing agent, known ones conventionally used for adsorbing and removing sulfur in kerosene, and (1) an acidic aqueous dispersion having a pH of 2 or less containing a nickel source and an aluminum source, a silicon source, A desulfurizing agent in which nickel is supported on a silica-alumina carrier obtained by mixing a basic aqueous solution containing an inorganic base and then calcining the resulting solid, (2) a pore specific surface area having a pore diameter of 3 mm or less. Is a desulfurizing agent in which nickel is supported on a carrier of 100 m ² / g or more, (3) nickel is supported on a carrier, and the hydrogen adsorption amount is 0.4 mmol /
g or more of a desulfurizing agent, and (4) a desulfurizing agent obtained by supporting a nickel component containing 95% by weight or more of metallic nickel on a carrier. The nickel carrying amount of these nickel-based desulfurizing agents is preferably 40% by weight or more based on the total amount of the desulfurizing agent, and particularly preferably in the range of 50 to 70% by weight. Such a nickel-based desulfurizing agent is preferably manufactured by a coprecipitation method. For example, a desulfurizing agent in which nickel is supported on a silica-alumina carrier can be manufactured by the following method.

First, an acidic aqueous solution or aqueous dispersion containing a nickel source and an aluminum source and a basic aqueous solution containing a silicon source and an inorganic base are prepared. Examples of the nickel source used in the former acidic aqueous solution or acidic aqueous dispersion include nickel chloride, nickel nitrate, nickel sulfate and hydrates thereof. Examples of the aluminum source include aluminum hydrates such as aluminum nitrate, pseudoboehmite, boehmite alumina, bayerite, and gibbsite, and γ-alumina. On the other hand, the silicon source used in the basic aqueous solution is not particularly limited as long as it is soluble in an alkaline aqueous solution and can be converted into silica by firing, and examples thereof include orthosilicic acid, metasilicic acid, and sodium salts thereof. Potassium salts, water glass, and the like. In addition, examples of the inorganic base include carbonates and hydroxides of alkali metals.

Next, the acidic aqueous solution or aqueous dispersion thus prepared and the basic aqueous solution are each mixed with 50 to 90 wt.
Heated to about ℃, mixed both, further 50 ~ 90 ℃
The reaction is completed by maintaining the temperature at about the same level. Next, the produced solid is sufficiently washed and then subjected to solid-liquid separation, or the produced solid is subjected to solid-liquid separation and thoroughly washed, and then the solid is subjected to a known method at about 80 to 150 ° C. Drying at the temperature of The desulfurizing agent in which nickel is supported on a silica-alumina carrier is obtained by calcining the dried product thus obtained, preferably at a temperature in the range of 200 to 400 ° C. The shape and size of the desulfurizing agent to be charged into the desulfurizer are not particularly limited, and examples of the shape include powder, granules, beads, and fibers. Further, a shape and a size that do not increase the pressure loss in the desulfurizer are preferable. If the pressure loss increases, the feed oil becomes difficult to flow, and the amount of oil that can be processed decreases, which is not preferable. Next, a specific driving method will be described.

First, referring to FIG. 1, a JIS oil having a sulfur content of 80 ppm by weight or less in a raw material oil tank 1 is preferably used.
No. 1 kerosene is fed by feed oil feed pump 6 to feed oil preheater 2
And heated, and then guided to the desulfurizer 3 to perform desulfurization treatment. In order to desulfurize the sulfur in the feedstock to a low level, it is important to maintain a part or all of the feedstock passing through the desulfurizer in a liquid phase. For this purpose, the temperature in the desulfurizer depends on the performance of the desulfurizing agent to be used and the type of raw material oil, but when using a nickel-based desulfurizing agent and desulfurizing kerosene under atmospheric pressure, several tens of degrees Celsius to It is preferable to maintain the temperature at about 230 ° C. For this purpose, the preheating temperature of the feedstock may be determined in consideration of heat radiation from the desulfurizer so that the temperature of the desulfurizer does not become higher than the above temperature range.
Specifically, it is preferable to heat the raw oil with the preheater 2 so that the temperature of the raw oil is slightly higher than a predetermined temperature of the desulfurizer 3. In the case of performing desulfurization treatment under pressure, a temperature at which the entire raw material oil does not vaporize at that pressure may be appropriately selected. In the case of pressurization, a pressure of usually less than 1 MPa is adopted.

The linear velocity of the feed oil in the desulfurizer 3 is generally 0.5 cm / min or less, preferably 0.2 cm / min or less. If the linear velocity exceeds 0.5 cm / min, it becomes difficult to maintain a low sulfur content for a long time, which is not preferable. To reduce the linear velocity, it is conceivable to increase the diameter (D). However, as described above, the L / D value is 8 or more,
In particular, since it is preferably 10 or more, L becomes large in order to satisfy this L / D value. Therefore, it is preferable to determine this linear velocity in consideration of the relationship with the total amount of the desulfurizing agent. The LHSV (liquid hourly space velocity) is not particularly limited, but is appropriately selected depending on the desulfurizing agent adsorption capacity. Considering the compactness of the apparatus, the LHSV is preferably 0.1 h ^-1 or more, and it is important to select a desulfurizing agent having such performance. The flow of the feedstock in the desulfurizer is partially or entirely upward (upflow)
Advantageously. By making the flow upward, when the raw oil is in a liquid phase under the desulfurization conditions, the raw oil can be brought into contact with the entire packed bed of the desulfurizing agent, and the entire desulfurizing agent can be effectively used for the desulfurization treatment.

As the desulfurization conditions, the pressure is usually from atmospheric pressure to
It is in the range of 0.9 MPa, preferably at atmospheric pressure. Also,
The temperature is usually from room temperature to 400 ° C., preferably from room temperature to 250 ° C.
Range. In addition, depending on the desulfurizing agent, performance may be obtained at a temperature at which the raw material oil vaporizes under the atmospheric pressure. In such a case, it is preferable to pressurize the desulfurizer to make a part or all of the raw oil into a liquid phase. When kerosene is used as a raw material oil and a nickel-based desulfurizing agent is used as a desulfurizing agent, desulfurization treatment is preferably performed at atmospheric pressure at a temperature of several tens of degrees Celsius to 230 degrees Celsius. There is no particular limitation on the coexisting gas in the desulfurization treatment, but it is preferable that a gas such as hydrogen does not coexist in view of downsizing of the apparatus.

When a nickel-based desulfurizing agent is used, hydrogen is usually supplied to a desulfurizer filled with the desulfurizing agent before starting operation. The desulfurizing agent is reduced. The raw oil desulfurized in this way is supplied to the vaporizer 4 and vaporized. The vaporization in the vaporizer 4 is performed at a temperature equal to or higher than a temperature at which the entire oil component of the base oil is gasified and equal to or lower than a temperature at which the base oil is thermally decomposed. When the feed oil is kerosene, the temperature range is usually 300 to 650 ° C, preferably 350 to 550 ° C. The temperature of the vaporizer is 300 ℃
If it is less than 1, the unvaporized portion of the feed oil remains in the vaporizer, and the heat transfer efficiency of the vaporizer is likely to be reduced or clogged. On the other hand, 65
If the temperature exceeds 0 ° C., the raw material oil is liable to be carbonized by thermal decomposition, and as a result, the heat transfer efficiency of the vaporizer may be reduced or clogged, which is not preferable. The desulfurized raw material gas vaporized in the vaporizer 4 is supplied to a reformer for hydrogen production. When the desulfurizer 3 is started from a state in which the temperature of the desulfurizer is lower than a predetermined temperature at which the desulfurizing agent can exhibit performance, the desulfurizer 3
It is anticipated that even if the feedstock heated by the feedstock preheater 2 installed upstream of the above is supplied and the temperature inside the desulfurizer is set to the above-mentioned predetermined temperature, the temperature does not immediately reach the predetermined temperature. . Depending on the desulfurizing agent, the desulfurizing performance is rapidly lowered below a predetermined temperature. When such a desulfurizing agent is used, the raw material oil which has not been sufficiently desulfurized for a short time is vaporized by the vaporizer 4. It is vaporized and supplied to a reformer for hydrogen production or supplied. As a result, there is a possibility that the catalyst life of the reformer is adversely affected.

Therefore, in the present invention, the desulfurizer 3
If the temperature of the desulfurizer is lower than the predetermined temperature, for example, (1) the raw oil which has been subjected to the desulfurization treatment is supplied to the desulfurizer through the raw oil preheater, and when the temperature of the desulfurizer reaches the predetermined temperature, Method of switching the feed of feedstock to the normal line to the feeder, or (2) feed the feedstock that has left the desulfurizer to the feedstock tank without feeding it to the vaporizer, and the temperature of the desulfurizer reaches the predetermined temperature. At this point, a method of supplying the desulfurization-treated raw oil that has exited the desulfurizer to the vaporizer is preferably used. In these methods, for example, a temperature detector is provided in a desulfurizer, and when a temperature lower than a predetermined temperature is detected, the valve is automatically switched, and when the temperature reaches the predetermined temperature, the valve is automatically set to a normal line. It is advantageous to provide a mechanism for switching to

In the above method (1), as a means for supplying the pre-desulfurized raw oil, a tank for storing the pre-desulfurized raw oil may be provided, or the raw oil may be separately desulfurized. Thus, a low sulfur feedstock may be prepared and supplied. In the latter case, another desulfurizer will be provided. The desulfurizer preferably has a sufficient desulfurization performance at a temperature lower than the above-mentioned predetermined temperature, and particularly preferably exhibits the desulfurization performance at room temperature. As a desulfurizing agent suitable for such a desulfurizer, for example, activated carbon, silica gel, zeolite, etc. carrying bromine or ammonia can be mentioned. Further, as another method, a method of not lowering the temperature of the desulfurizer below a predetermined temperature even when the fuel cell is stopped can be considered. In this case, a means capable of heating even when the fuel cell is stopped is provided, and the feed oil is circulated so as not to lower the temperature of the desulfurizer below a predetermined temperature. A separate line should be provided upstream of the vaporizer so that the circulated feedstock does not enter the vaporizer, and returned to the original feedstock tank or stored separately in a dedicated tank for desulfurization processing feedstock. May be.
According to this operation method, when JIS No. 1 kerosene is used as a feed oil, a kerosene vaporized gas having a sulfur content of 0.1 ppm by weight or less can be obtained. The vaporized gas is mixed with another raw material such as steam, and brought into contact with a reforming catalyst in the reformer, for example, a steam reforming catalyst, thereby obtaining hydrogen for a fuel cell.

[0024]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Preparation Example 1 Preparation of nickel-based desulfurizing agent 50.9 g of nickel chloride was dissolved in 500 ml of water, and 0.6% of alumina (pseudo boehmite) was used as a carrier.
g, and then a 1 mol / liter nitric acid aqueous solution 2
0 ml was added to adjust to pH 1 to prepare solution (A). On the other hand, after dissolving 33.1 g of sodium carbonate in 500 ml of water, 11.7 g of water glass (Si
(O ₂ concentration 29% by weight) was added to prepare solution (B). Next, after the above solution (A) and solution (B) were heated to 80 ° C., respectively, the two were instantaneously mixed, and the temperature of the mixed solution was raised to 80 ° C.
While stirring for 1 hour. Thereafter, the product was sufficiently washed with 60 liters of distilled water, and then filtered,
Then, the solid matter was dried for 12 hours by a 120 ° C blast dryer, and further baked at 300 ° C for 1 hour,
A desulfurizing agent in which 63% by weight of nickel was supported on a silica-alumina carrier was obtained. The desulfurizing agent had a hydrogen adsorption of 0.75.
Mmol / g.

Example 1 Using a kerosene desulfurization vaporization test apparatus having the structure shown in FIG. 3, a desulfurization vaporization test of a commercial kerosene having a sulfur content of 66 ppm by weight was performed. Straight tube stainless steel desulfurizer 3 with a reaction tube diameter D of 2 cm
Was charged with 60 ml of the nickel-based desulfurizing agent 19 obtained in Preparation Example 1. At this time, the length L of the packed bed of the desulfurizing agent is 2
Since it was 1 cm, the L / D value was 10.5. The desulfurizer 3 has a valve 8 and a valve 8, respectively, at an inlet and an outlet.
8 'and 9, 9' are provided and are detachable. In addition, 10 and 11 are mounting parts. First, the desulfurizer 3 filled with the desulfurizing agent 19 is separately attached to the equipment, and after performing hydrogen reduction at 380 ° C. in advance, as shown in FIG.
It was attached to this experimental device. After the mounting, the outside of the desulfurizer 3 was covered with a heat insulating material 14 made of ceramic wool.

Next, the commercial kerosene stored in the feedstock oil tank 1 is passed by the feedstock oil pump 6 to the feedstock preheater 2 having a tubular reactor filled with ceramic balls 16 at a flow rate of 25 ml / h. Oiled. This preheater has an electric furnace 13
The kerosene was heated to 200 ° C. and then flowed into the desulfurizer 3. When the temperature inside the desulfurizer was measured, the inlet was 180 ° C and the outlet was 150 ° C. Considering the distillation properties of kerosene, almost all kerosene was in a liquid phase in the desulfurizer 3. At this time, the pressure inside the desulfurizer 3 is atmospheric pressure, the linear velocity of kerosene is 0.13 cm / min, L
The HSV was 0.3 h ^-1 .

As a result of sampling and analyzing the desulfurized kerosene flowing out of the desulfurizer 3, the kerosene exiting the desulfurizer 3 was processed until the amount of kerosene passed per unit of desulfurizer was 450 ml / ml-desulfurizer. The sulfur content is 0.1 weight p
pm or less. From another experiment, the saturated adsorption of sulfur in the desulfurizing agent was found to be 3.5% by weight of the desulfurizing agent. The maximum amount capable of processing 66 ppm by weight of kerosene was 500 ml / ml-desulfurizing agent. From these results, it can be seen that when the present desulfurizer is used, desulfurized kerosene having a sulfur content of 0.1 ppm by weight or less can be obtained up to about 90% of the saturated adsorption capacity of the desulfurizing agent. Next, the desulfurization-treated kerosene flowing out of the desulfurizer 3 was stored in the tank 17, and a vaporization experiment was performed. Tank 17
, The desulfurized kerosene was passed through the electric heating type vaporizer 4 by the pump 18. The vaporizer 4 is a tube type reactor filled with ceramic balls 16, and is heated to a predetermined temperature in an electric furnace 15. The experiment was performed with the temperature of the vaporizer 4 set to 500 ° C. A tube 20 provided with a glass window was installed immediately downstream of the vaporizer, and the state of vaporization was observed. However, no large droplets were attached to the glass window, and the vaporization was good. After the experiment, the ceramic balls 1 of the vaporizer 4 were removed.
No. 6 was extracted and observed, but no adhesion of tar-like substances or coloring of the ceramic ball due to carbon deposition was observed.

Example 2 In Example 1, the flow rate of kerosene was changed to 60 ml / liter.
Except having set it to h, it implemented similarly to Example 1. At this time, the L / D value in the desulfurizer was 10.5, and the linear velocity of kerosene was 0.32 cm / min. The amount of kerosene passing per unit of desulfurizing agent is 300 ml / ml-the sulfur content of kerosene that exited the desulfurizer at the time of the desulfurizing agent is 0.1 ppm by weight.
Got more. This indicates that desulfurized kerosene having a sulfur content of 0.1 ppm by weight or less can be obtained up to about 60% of the saturated adsorption capacity of the desulfurizing agent. Example 3 Example 3 was carried out in the same manner as in Example 1 except that the desulfurizer 3 was charged with 20 ml of the nickel-based desulfurizing agent 19 obtained in Preparation Example 1. In this case, since the length L of the packed bed of the desulfurizing agent was 8 cm, L / D = 4, and the linear velocity of kerosene was 0.13 cm / min. The amount of kerosene passed per unit of desulfurizing agent is 100 ml / ml-the sulfur content of kerosene exiting the desulfurizer at the time of the desulfurizing agent is 0.1 ppm by weight.
Got more. This indicates that desulfurized kerosene having a sulfur content of 0.1 wt ppm or less can be obtained up to about 20% of the saturated adsorption capacity of the desulfurizing agent.

Example 4 Example 4 was carried out in the same manner as in Example 1, except that the flow rate of kerosene was changed to 120 ml / h. In this case, the L / D value in the desulfurizer was 10.5, and the linear velocity of kerosene was 0.64 cm / min. The flow rate of kerosene per unit of desulfurizing agent is 150ml / ml-
At the time of the desulfurizing agent, the kerosene that has exited the desulfurizer has a sulfur content of 0.1 weight p.
pm. This indicates that desulfurized kerosene having a sulfur content of 0.1 ppm by weight or less can be obtained up to about 30% of the saturated adsorption capacity of the desulfurizing agent. As can be seen from the above results, the L / D value in the desulfurizer is preferably 8 or more, and the linear velocity of kerosene is preferably 0.5 cm / min or less.

[0030]

According to the fuel cell desulfurization apparatus of the present invention,
It is possible to desulfurize raw oil such as kerosene for a long time to a sulfur content of 0.1 ppm by weight or less, and when the desulfurizing agent deteriorates in performance, it is easy to replace the desulfurizing agent or desulfurizer. The vaporized gas of the treated feedstock can be efficiently supplied to a reformer for hydrogen production.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an example of a desulfurization device for a fuel cell according to the present invention.

FIG. 2 is a perspective view showing an example of a desulfurizer having a different shape used in the desulfurizer for a fuel cell according to the present invention.

FIG. 3 is a configuration diagram of a kerosene desulfurization vaporization experimental apparatus used in Examples.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 feed oil tank 2 feed oil preheater 3 desulfurizer 4 vaporizer 5 charge tank 6 feed oil supply pump 13 electric furnace 14 heat insulator 15 electric furnace 16 ceramic ball 17 tank 18 pump 19 desulfurizer 20 gas window provided tube

Claims (13)

[Claims] 1. A feedstock tank, a feedstock preheater for heating feedstock supplied from the feedstock tank, a desulfurizer for desulfurizing feedstock heated by the feedstock preheater, and the desulfurizer A desulfurization apparatus for a fuel cell, comprising, as a main component, a vaporizer for vaporizing a feed oil desulfurized in step (1) and supplying the vaporized oil to a reformer. 2. The fuel cell desulfurization apparatus according to claim 1, wherein the feed oil is kerosene. 3. The desulfurizer for a fuel cell according to claim 1, wherein the desulfurizer is a detachable cartridge type. 4. The desulfurizer for a fuel cell according to claim 1, wherein the desulfurizer is a U-shaped, folded or jacket type. 5. The fuel cell according to claim 1, wherein in the desulfurizer, when the length of the desulfurizing agent packed layer is L and the diameter of the desulfurizing agent packed layer is D, L / D is 8 or more. For desulfurization equipment. 6. The desulfurization device for a fuel cell according to claim 1, wherein the raw oil preheater and / or the vaporizer are heated by using the exhaust heat of the fuel cell. 7. A method for operating a desulfurization device for a fuel cell, comprising using the desulfurization device according to claim 1 to desulfurize a raw material oil, vaporize the oil, and supply it to a reformer. . 8. The linear velocity of the feed oil in the desulfurizer is 0.5
The operation method according to claim 7, wherein the pressure is not more than cm / min. 9. The operating method according to claim 7, wherein the desulfurization treatment in the desulfurizer is performed at atmospheric pressure and in the absence of hydrogen. 10. The desulfurizer, wherein a part or all of the feedstock is desulfurized in an upward flow state.
10. The driving method according to 8 or 9. 11. When the temperature of the desulfurizer is lower than a predetermined temperature, the pre-desulfurized feedstock is supplied to the desulfurizer through a feedstock preheater, and when the temperature of the desulfurizer reaches the predetermined temperature. 11. The operation method according to claim 7, wherein the supply of the feedstock oil to the desulfurizer is switched to a normal line. 12. When the temperature of the desulfurizer is lower than a predetermined temperature, the feed oil leaving the desulfurizer is returned to the feed oil tank without being supplied to the vaporizer, and the temperature of the desulfurizer reaches the predetermined temperature. The operation method according to any one of claims 7 to 10, wherein the desulfurization-treated raw material oil that has exited the desulfurizer at a point in time is supplied to the vaporizer. 13. The vaporization temperature in the vaporizer is 300 to 6
The operating method according to claim 7, wherein the temperature is 00C.