KR20090118865A - Desulfurizing device, fuel cell system and reforming system - Google Patents

Abstract

PURPOSE: A desulfurizing device, a fuel cell system and a reforming system is provided to conveniently realize the feeding liquid of liquid fuel at a lower flow rate with low cost. CONSTITUTION: A desulfurizing device comprises a desulfurizer containing a desulfurization catalyst which removes sulfur content from a liquid fuel for supplying reformate gas containing hydrogen to a reformer(5); a heating unit which heats the desulfurization catalyst; a liquid fuel injection unit for injecting liquid fuel within the desulfurizer; a liquid fuel discharge unit which discharges liquid fuel from the desulfurizer; a temperature measurement unit; a pressure measurement unit; a heating unit; and a control unit.

Description

Desulfurizing device, fuel cell system and reforming system

The present invention relates to a desulfurization apparatus for removing sulfur content from liquid fuel, a fuel cell system having such a desulfurization apparatus, and a reforming system.

In a fuel cell system, a reformer containing hydrogen is produced by the reformer, and the reformed gas is used by the fuel cell stack to generate power. In such a fuel cell system, in order to prevent deterioration of the reforming catalyst when liquid fuel such as kerosene is supplied to the reformer as a reforming raw material, it is necessary to install a desulfurizer for removing sulfur content from the liquid fuel (for example, Japanese Patent Laid-Open Publication 2004-323285).

(1st aspect of this invention)

By the way, in the desulfurization unit, it is necessary to heat the desulfurization catalyst in order to promote the catalytic reaction, but the liquid fuel is vaporized by the temperature rise according to this, which makes it difficult to efficiently desulfurize and deteriorates the desulfurization catalyst. There is.

Accordingly, the first aspect of the present invention has been made in view of such circumstances, and an object thereof is to provide a desulfurization apparatus capable of preventing vaporization of liquid fuel, and a fuel cell system having such a desulfurization apparatus.

In order to achieve the above object, the desulfurization apparatus according to the first aspect of the present invention is a desulfurization unit containing a desulfurization catalyst for removing sulfur content from a liquid fuel for supplying a reformer that generates a reforming gas containing hydrogen, and a desulfurization catalyst Heating means for heating the liquid, liquid fuel introduction means for introducing the liquid fuel into the desulfurizer, liquid fuel derivation means for deriving the liquid fuel from the desulfurizer, temperature measuring means for measuring the temperature of the liquid fuel in the desulfurizer, And pressure measuring means for measuring the pressure of the liquid fuel in the desulfurizer, and control means for controlling the heating means, the liquid fuel introduction means, and the liquid fuel derivation means, wherein the control means has a predetermined temperature measured by the temperature measuring means. The pressure measured by the pressure measuring means is equal to or higher than the saturated vapor pressure of the liquid fuel at a predetermined temperature. The heating means, the liquid fuel introduction means and the liquid fuel derivation means are controlled so as to be a predetermined pressure below the internal pressure of the desulfurization unit.

In this desulfurization apparatus, the heating means, the liquid fuel introduction means and the liquid fuel derivation means are controlled by the control means so that the temperature measured by the temperature measuring means, i.e., the temperature of the liquid fuel in the desulfurizer, is for example a catalyst of the desulfurization catalyst. It becomes a predetermined temperature which can accelerate reaction. The pressure measured by the pressure measuring means, i.e., the pressure of the liquid fuel in the desulfurizer, becomes a predetermined pressure equal to or higher than the saturated vapor pressure of the liquid fuel at a predetermined temperature and equal to or lower than the internal pressure of the desulfurizer. Therefore, even if the temperature of the liquid fuel in the desulfurizer is raised, it is possible to prevent the liquid fuel from vaporizing. In addition, a sulfur content is the meaning containing a sulfur and a sulfur compound. In addition, the internal pressure of a desulfurizer means the maximum value of the internal pressure which a container containing a desulfurization catalyst can endure.

In the desulfurization apparatus according to the first aspect of the present invention, the control means increases the amount of introduction of the liquid fuel by the liquid fuel introduction means and increases the liquid by the liquid fuel derivation means when the pressure measured by the pressure measurement means is increased. In the case of reducing the amount of fuel drawn out and lowering the pressure measured by the pressure measuring means, it is desirable to reduce the amount of liquid fuel introduced by the liquid fuel introducing means and to increase the amount of liquid fuel derived by the liquid fuel drawing means. desirable. According to this configuration, the pressure measured by the pressure measuring means, that is, the pressure of the liquid fuel in the desulfurizer can be raised or lowered quickly and surely.

In addition, the fuel cell system according to the first aspect of the present invention uses the desulfurization apparatus, a reformer for producing reformed gas containing hydrogen using a liquid fuel from which sulfur content is removed by the desulfurization apparatus, and a reformer for generating the reformed gas containing hydrogen. And a fuel cell stack for generating electricity using the reformed gas.

According to this fuel cell system, since the desulfurization apparatus is provided, the liquid fuel can be prevented from vaporizing even if the temperature of the liquid fuel in the desulfurizer is raised.

According to the first aspect of the present invention, vaporization of the liquid fuel can be prevented.

(2nd aspect of this invention)

In a fuel cell system, a reformer containing hydrogen is produced by the reformer, and the reformed gas is used by the fuel cell stack to generate power. In such a fuel cell system, in order to prevent deterioration of the reforming catalyst when liquid fuel such as kerosene is supplied to the reformer as a reforming raw material, it is necessary to install a desulfurizer for removing sulfur content from the liquid fuel (for example, Japanese Patent Laid-Open Publication 2004-323285).

By the way, in the desulfurization unit, it is necessary to heat the desulfurization catalyst in order to promote the catalytic reaction, but it takes a considerable time to raise the desulfurization catalyst from normal temperature to a predetermined desulfurization temperature (for example, 200 ° C). For this reason, there is a problem that it takes time until it is restarted if it is stopped once.

Accordingly, the second aspect of the present invention has been made in view of the above circumstances, and an object thereof is to provide a desulfurization apparatus capable of shortening the time until restarting, and a fuel cell system having such a desulfurization apparatus. .

In order to achieve the above object, the desulfurization apparatus according to the second aspect of the present invention is a desulfurization unit containing a desulfurization catalyst for removing sulfur content from a liquid fuel for supplying a reformer that generates a reforming gas containing hydrogen, and a desulfurization catalyst Heating means for heating the liquid, liquid fuel introduction means for introducing the liquid fuel into the desulfurizer, liquid fuel derivation means for deriving the liquid fuel from the desulfurizer, temperature measuring means for measuring the temperature of the liquid fuel in the desulfurizer, And control means for controlling the heating means, the liquid fuel introduction means, and the liquid fuel derivation means, wherein the control means introduces the liquid fuel to stop the supply of the liquid fuel from the desulfurizer when a pause signal is input. While controlling at least one of the means and the liquid fuel derivation means, the temperature measured by the temperature measuring means is higher than the normal temperature. Further, the heating means is controlled so that the predetermined temperature is lower than the temperature during normal operation.

In this desulfurization apparatus, when a pause signal is input, at least one of the liquid fuel introduction means and the liquid fuel derivation means is controlled by the control means, so that the supply of the liquid fuel in the desulfurizer is stopped. At this time, the heating means is controlled by the control means, so that the temperature measured by the temperature measuring means, that is, the temperature of the liquid fuel in the desulfurizer, is maintained at a predetermined temperature higher than the normal temperature and lower than the temperature during normal operation. As a result, compared with the case where the desulfurization apparatus is stopped and the temperature is reduced to room temperature, the time until heating to a predetermined desulfurization temperature, that is, during normal operation, is shortened, so that the time until restart is shortened. We can plan. In addition, a sulfur content is the meaning containing a sulfur and a sulfur compound.

In the desulfurization apparatus according to the second aspect of the present invention, the desulfurization apparatus further includes a storage container for temporarily storing the liquid fuel derived by the liquid fuel derivation means, and a storage amount measuring means for measuring the storage amount of the liquid fuel stored in the storage container. The storage amount measuring means preferably outputs a pause signal to the control means when the storage amount reaches the predetermined storage amount. According to this structure, by supplying liquid fuel to a temporary storage container, supply of liquid fuel to a reformer etc. can be stabilized. In addition, when the amount of storage in the storage container reaches a predetermined amount of storage, the storage amount measuring means outputs a pause signal to the control means, so that, for example, damage to the storage container due to the storage amount over can be prevented.

Further, the fuel cell system according to the second aspect of the present invention is a reformer for producing a reformed gas containing hydrogen using the desulfurization apparatus, a liquid fuel from which sulfur is removed by the desulfurization apparatus, and a reformer for generating a reformer gas containing hydrogen. And a fuel cell stack for generating electricity using the reformed gas.

According to this fuel cell system, since the desulfurization apparatus is provided, the time to restart can be shortened.

According to the second aspect of the present invention, the time until restart can be shortened.

(Third aspect of the present invention)

In a fuel cell system, a reformer containing hydrogen is produced by the reformer, and the reformed gas is used by the fuel cell stack to generate power. In such a fuel cell system, in order to prevent deterioration of the reforming catalyst when liquid fuel such as kerosene is supplied to the reformer as a reforming raw material, it is necessary to install a desulfurizer for removing sulfur content from the liquid fuel (for example, Japanese Patent Laid-Open Publication 2004-323285).

However, in the desulfurizer, the pressure decreases as the temperature of the liquid fuel decreases. For example, when the operation is stopped, the pressure is lowered by about 20% than in normal operation. At this time, the liquid fuel may be vaporized to deteriorate the desulfurization catalyst. In addition, when the pressure in the desulfurizer becomes negative, problems such as breakage of the desulfurizer and mixing of air to the desulfurizer at the time of restarting of operation may also occur.

Accordingly, the third aspect of the present invention has been made in view of the above circumstances, and it is therefore desirable to provide a desulfurization apparatus capable of preventing adverse effects on the desulfurizer due to a pressure drop, and a fuel cell system having such a desulfurization apparatus. The purpose.

In order to achieve the above object, the desulfurization apparatus according to the third aspect of the present invention includes a desulfurizer and a desulfurizer containing a desulfurization catalyst for removing sulfur content from a liquid fuel for supplying to a reformer for producing reformed gas containing hydrogen. Liquid fuel introduction means for introducing liquid fuel into the liquid, liquid fuel derivation means for deriving the liquid fuel from the desulfurizer, temperature measuring means for measuring the temperature of the liquid fuel in the desulfurizer, and pressure of the liquid fuel in the desulfurizer. And a pressure measuring means for measuring, and a control means for controlling the liquid fuel introduction means and the liquid fuel derivation means, wherein the control means is such that the temperature measured by the temperature measuring means is equal to or less than a predetermined temperature lower than the temperature during normal operation. In this case, the liquid fuel introduction means and the pressure so that the pressure measured by the pressure measuring means is a predetermined pressure of a positive pressure and It characterized in that the control fuel element derivation means.

In this desulfurization apparatus, when the temperature measured by the temperature measuring means, i.e., the temperature of the liquid fuel in the desulfurizer, becomes lower than or equal to a predetermined temperature (e.g., 100 deg. C) lower than the temperature in normal operation (e.g., 200 deg. C). The liquid fuel introduction means and the liquid fuel derivation means are controlled by the control means, whereby the pressure measured by the pressure measuring means becomes a predetermined pressure at a positive pressure (more than negative pressure). Therefore, even when the pressure is lowered due to the decrease in the temperature of the liquid fuel at the time of stopping operation, for example, since the predetermined pressure is maintained at a constant pressure, for example, the vaporization of the liquid fuel due to the pressure drop or the desulfurizer It is possible to prevent adverse effects on the desulfurizer such as breakage. In addition, a sulfur content is the meaning containing a sulfur and a sulfur compound.

In the desulfurization apparatus according to the third aspect of the present invention, when the control means raises the pressure measured by the pressure measuring means, the liquid fuel introduction means increases the amount of liquid fuel introduced by the liquid fuel introduction means and at the same time the liquid by the liquid fuel derivation means. In the case of reducing the amount of fuel drawn out and lowering the pressure measured by the pressure measuring means, it is desirable to reduce the amount of liquid fuel introduced by the liquid fuel introducing means and to increase the amount of liquid fuel derived by the liquid fuel drawing means. desirable. According to this configuration, the pressure measured by the pressure measuring means, that is, the pressure of the liquid fuel in the desulfurizer can be raised or lowered quickly and surely.

In addition, the fuel cell system according to the third aspect of the present invention uses the desulfurization apparatus, a reformer for generating a reformed gas containing hydrogen using a liquid fuel from which sulfur content is removed by the desulfurization apparatus, and a reformer produced by the reformer. And a fuel cell stack for generating electricity using the reformed gas.

According to this fuel cell system, since the desulfurization apparatus is provided, even if the pressure decreases due to the decrease in the temperature of the liquid fuel, adverse effects on the desulfurizer resulting from this can be prevented.

According to the 3rd aspect of this invention, the bad influence to the desulfurizer resulting from a pressure fall can be prevented.

(4th aspect of this invention)

In a fuel cell system, a reformer containing hydrogen is produced by the reformer, and the reformed gas is used by the fuel cell stack to generate power. In such a fuel cell system, in order to prevent deterioration of the reforming catalyst when liquid fuel such as kerosene is supplied to the reformer as a reforming raw material, it is necessary to install a desulfurizer for removing sulfur content from the liquid fuel (for example, Japanese Patent Laid-Open Publication 2004-323285).

However, since gas such as methane gas or hydrogen gas is discharged from the desulfurizer together with the liquid fuel, there is a possibility that the rear end of the desulfurizer is adversely affected, such as quantitative supply of the liquid fuel to the reformer is hindered.

Therefore, the fourth aspect of the present invention has been made in view of such circumstances, and a fuel cell system having a desulfurization apparatus capable of reliably removing sulfur content from a liquid fuel while preventing adverse effects on the rear end, and such a desulfurization apparatus. The purpose is to provide.

In order to achieve the above object, the desulfurization apparatus according to the fourth aspect of the present invention includes a desulfurizer for removing sulfur content from a liquid fuel for supplying to a reformer for producing reformed gas containing hydrogen, and a liquid fuel discharged from the desulfurizer. And a gas-liquid separation container for storing gas, a liquid fuel discharge line for discharging liquid fuel from the gas-liquid separation container, a gas discharge line for discharging gas from the gas-liquid separation container, and a gas discharge line. Valve for opening and closing the valve, and a throttle formed in the gas discharge line on the downstream side of the on / off valve and inhibiting the flow of gas (throttle for suppressing a drop in pressure in the desulfurizer when the flow of gas is opened). It characterized by having a.

In this desulfurization apparatus, the gas discharged from the desulfurizer together with the liquid fuel is separated from the liquid fuel in the gas-liquid separation vessel and discharged from the gas-liquid separation vessel through the gas discharge line. For this reason, the liquid fuel mixed with gas is prevented from being supplied to the rear end of the desulfurization apparatus. Moreover, the gas discharge line is provided with the throttle which inhibits gas flow in the downstream side of the on-off valve which opens and closes gas flow. For this reason, even if the flow of gas is opened by the on-off valve for discharging gas from the gas-liquid separation vessel through the gas discharge line, the drop in pressure in the desulfurizer is suppressed by the throttle. Therefore, according to this desulfurization apparatus, it becomes possible to reliably remove sulfur content from liquid fuel, preventing the bad influence to a rear end. In addition, a sulfur content is the meaning containing a sulfur and a sulfur compound.

In the desulfurization apparatus according to the fourth aspect of the present invention, in the case where the flow valve closes the flow of gas, when the amount of gas in the gas-liquid separation vessel exceeds a predetermined amount, the flow is divided into a plurality of times. It is preferable to open. According to this structure, the fall of the pressure in a desulfurizer at the time of opening | release of gas by a switching valve in order to discharge gas from a gas-liquid separation container via a gas discharge line can be suppressed more reliably.

In the desulfurization apparatus according to the fourth aspect of the present invention, the gas discharge line is preferably connected to a burner for heating the reforming catalyst of the reformer. According to this structure, the gas discharged | emitted with the liquid fuel from a desulfurizer can be utilized effectively as a fuel of a burner.

In addition, the fuel cell system according to the fourth aspect of the present invention uses a desulfurization apparatus, a reformer for generating reformed gas containing hydrogen using a liquid fuel from which sulfur is removed by the desulfurization apparatus, and a reformer for generating the reformed gas containing hydrogen. And a fuel cell stack for generating electricity using the reformed gas.

According to this fuel cell system, since the desulfurization apparatus is provided, it is possible to reliably remove sulfur from the liquid fuel while preventing adverse effects on the rear end of the desulfurization apparatus.

According to the fourth aspect of the present invention, sulfur content can be reliably removed from the liquid fuel while preventing adverse effects on the rear end of the desulfurization apparatus.

(5th aspect of this invention)

BACKGROUND ART Fuel cell systems have been developed by reforming liquid fuels to produce reformed gas containing hydrogen and reacting the reformed gas with a gas containing oxygen. In the case where a fuel containing sulfur content such as kerosene is used as the raw fuel to be introduced into the fuel cell system, the reforming catalyst is exposed to the sulfur content in the raw fuel, and poisoning of the sulfur deteriorates the reforming performance. For this reason, as a fuel cell system, sulfur content may be removed from a raw fuel before reforming reaction (for example, refer Unexamined-Japanese-Patent No. 2004-213941).

By the way, when the sulfur concentration contained in a raw fuel is comparatively high, in order to remove sulfur content sufficiently, it is conceivable to promote the desulfurization reaction by making the pressure in a desulfurizer higher than atmospheric pressure. However, when the desulfurizer is set to a high pressure, the high pressure liquid fuel flows into the reformer after the desulfurizer. In this case, it is difficult to control the flow rate of the high pressure liquid fuel, the reforming performance is lowered, and the performance as the fuel cell system is lowered. In addition, when the desulfurizer is used at a high pressure, durability problems arise in facilities such as pipes, reaction vessels, and pumps at the rear end, so that these facilities need to be made to support high pressure, and the cost is high.

Accordingly, the fifth aspect of the present invention is to provide a fuel cell system which can improve the durability of a facility at a rear stage of a desulfurizer even when desulfurizing under high pressure, and realizes low cost and prevents performance degradation. do.

In the fuel cell system according to the fifth aspect of the present invention, a desulfurizer for removing sulfur from a liquid raw fuel under pressure higher than atmospheric pressure to generate a liquid fuel, an open gas extraction hole is formed, and discharged from a desulfurizer. A storage tank for storing liquid fuel, a delivery pump for sending liquid fuel from within the storage tank, a reformer disposed downstream of the delivery pump and reforming the liquid fuel to generate reformed gas; A fuel cell stack for generating power using reformed gas is provided.

In the fuel cell system according to the fifth aspect of the present invention, a storage tank for storing liquid fuel is disposed between a desulfurizer and a reformer for desulfurization under high pressure, and the storage tank is formed with a gas extraction hole open to the atmosphere. have. Therefore, when the high-pressure liquid fuel desulfurized in the desulfurizer flows into the oil storage tank, the gas contained in the liquid fuel is separated from the liquid fuel, escapes from the gas extraction hole, and is discharged from the oil storage tank. Since the gas contained in the liquid fuel is released, the reliability of the flow rate control of the liquid fuel can be increased on the downstream side than the storage tank. For this reason, the flow volume of the liquid fuel which flows into a reformer can be controlled reliably, and the fall of reforming performance can be prevented. In addition, since the liquid fuel in the high pressure state does not flow in the downstream side from the oil storage tank, there is no need of a facility corresponding to a high pressure, and the durability of the equipment at the rear end of the oil storage tank can be improved, and low cost can be realized.

In the fuel cell system according to the fifth aspect of the present invention, preferably, a positive pressure pump for conveying the raw fuel at a constant pressure in the desulfurization unit, and a capillary tube disposed downstream from the desulfurizer and upstream from the storage tank. It is provided.

In this case, the raw fuel flows into the desulfurizer at a constant pressure, and the flow rate from the desulfurizer is throttled. For this reason, the pressure in a desulfurizer can be made higher than atmospheric pressure, and the flow rate of a raw fuel (liquid fuel) can be kept low, without using an expensive pump. In general, it is also possible to use an orifice, a needle valve, or the like instead of the capillary tube. However, since the flow path of the orifice portion is limited, the diameter of the orifice portion must be made extremely small in order to reduce the flow rate of the high-pressure liquid fuel discharged from the desulfurizer. Here, in the desulfurization unit, the desulfurization catalyst is desulfurized by the desulfurization catalyst, but the desulfurization catalyst may be contained in the liquid fuel from which the sulfur content is removed by the desulfurization unit. For this reason, when an orifice, a needle valve, etc. are used, the desulfurization catalyst which flowed out from the desulfurizer may be blocked by the flow path of an orifice part. On the other hand, since the capillary tube is used in the fuel cell system which concerns on this invention as mentioned above, the inner diameter of a capillary tube can be enlarged to some extent according to the length of a capillary tube. For this reason, clogging by a desulfurization catalyst becomes extremely difficult to occur.

In the fuel cell system according to the fifth aspect of the present invention, Preferably, a liquid-liquid separation vessel for separating the liquid fuel and gas discharged from the desulfurizer, a liquid fuel discharge line for discharging the liquid fuel from the gas-liquid separation vessel, A gas discharge line for discharging gas from the gas-liquid separation vessel, an on / off valve formed in the gas discharge line to open and close the flow of gas, and a downstream side of the on / off valve in the gas discharge line, A flow meter formed in the liquid fuel discharge line; the capillary tube is formed upstream of the flow meter in the liquid fuel discharge line; On the downstream side, it is connected with a liquid fuel discharge line.

In this case, the gas discharged from the desulfurizer together with the liquid fuel is separated from the liquid fuel in the gas-liquid separation vessel and discharged from the gas-liquid separation vessel through the gas discharge line. In the gas discharge line, a throttle is provided on the downstream side of the on / off valve for opening and closing the flow of gas. For this reason, even if the flow of gas is opened by the on-off valve for discharging gas from the gas-liquid separation vessel through the gas discharge line, the drop in pressure in the desulfurizer is suppressed by the throttle. Therefore, by maintaining the pressure in the desulfurizer at a high pressure, it becomes possible to reliably remove the sulfur content from the raw fuel. On the other hand, the liquid fuel is introduced into the storage tank through the liquid fuel discharge line. Since the flowmeter is formed in the liquid fuel discharge line, it is possible to stably measure the flow rate of the liquid fuel separated from the gas.

In the fuel cell system according to the fifth aspect of the present invention, preferably, the water level sensor for detecting the low and high water level of the liquid fuel in the low oil tank, and the time from when the water level sensor detects the low water level to detect the high water level And a calculating means for calculating a flow rate of the liquid fuel based on the timer for measuring the pressure and the measurement time by the timer.

In this case, the water level sensor measures the time from the low water level detection until the high water level is detected by the timer, and the calculation means calculates the flow rate of the liquid fuel based on the measurement time by the timer. There is no need to provide separately. This can further reduce the cost.

In the fuel cell system according to the fifth aspect of the present invention, preferably, the lower part of the storage tank functions as a catalyst piece storage unit for collecting the desulfurization catalyst pieces introduced together with the liquid fuel from the desulfurization unit, and the liquid fuel in the storage tank. The inlet and outlet of are located above the reservoir of the catalyst piece.

In this case, the desulfurization catalyst which flowed out together with the liquid fuel from the desulfurization unit can be collected in the oil storage tank so as not to flow into the reformer of the subsequent stage. In addition, since the inlet and outlet of the liquid fuel in the oil storage tank are located above the storage portion of the catalyst piece, the catalyst accumulated in the storage portion of the catalyst piece rises by the inflow and outflow of the liquid fuel, flows out of the storage tank and flows into the reformer. Can be suppressed.

In the fuel cell system according to the fifth aspect of the present invention, preferably, an oil pan disposed below the oil storage tank, one opening is disposed in the oil storage tank, and the other opening is disposed outside the oil storage tank, An overflow pipe disposed toward the fan and a leak sensor disposed in the oil pan.

In this case, even if the liquid fuel is filled in the oil storage tank for some reason, the liquid fuel flows through the overflow pipe to the oil pan. The leak sensor disposed in the oil pan can detect that the liquid fuel has flowed into the oil pan.

The fuel cell system according to the fifth aspect of the present invention is preferably provided with a burner for heating the reformer and a gas discharge line for using the effluent gas flowing out of the gas extraction hole as the fuel for combustion.

In this case, it is possible to prevent the outflow gas flowing out of the gas extraction hole from flowing around the fuel cell system. In addition, since the outflow gas is used as the fuel of the burner, it can contribute to energy saving.

According to the fuel cell system according to the fifth aspect of the present invention, even in the case of desulfurization under high pressure, the durability of the equipment at the rear stage of the desulfurizer can be improved, low cost can be realized, and performance deterioration can be prevented.

(6th aspect of this invention)

In fuel cell systems, liquid fuel or the like is used as a raw fuel, and the liquid fuel or the like is reformed in a reformer to produce a reformed gas containing hydrogen, and the reformed gas is reacted with a gas containing oxygen.

By the way, when a liquid fuel containing sulfur content, such as kerosene, is used, the reforming catalyst is exposed to the sulfur content present in the liquid fuel, and the reforming catalyst is poisoned with sulfur, resulting in deterioration of performance such as shortening of life. It occurs. For this reason, in order to prevent deterioration of a reforming catalyst, a fuel cell system generally includes a desulfurizer for removing sulfur content from liquid fuel (see, for example, Japanese Unexamined Patent Publication No. 2004-213941).

By the way, in order to express the performance of a desulfurization catalyst, it is preferable to make temperature in a desulfurizer high temperature (for example, about 200 degreeC). In this way, when the desulfurizer is at a high temperature, gas (methane gas, hydrogen gas, etc.) is generated, so that the flow rate of the liquid fuel (kerosene) to be supplied is easily lowered, or the liquid fuel (kerosene) is vaporized and caulked ( Since carbon precipitates on the surface of the desulfurization catalyst, and the durability of the desulfurization catalyst tends to be lowered, so that the pressure in the desulfurizer is set to a high pressure (for example, about 0.5 MPa) in order to suppress them. desirable.

However, when the desulfurizer is subjected to high temperature and high pressure, the flow rate of the liquid fuel increases. For this reason, in a small fuel cell system that needs to supply liquid fuel at extremely low flow rate (for example, 10 g / min or less in a 1 kW fuel cell system), the flow rate of the liquid fuel can be reduced. The challenge was to control it low. At this time, it is conceivable to use a low flow rate pump, but the low flow rate pump is extremely expensive and not a realistic option.

It is therefore an object of the sixth aspect of the present invention to provide a fuel cell system and a reforming system capable of easily and at low cost delivering liquid fuel at low flow rates.

The fuel cell system according to the sixth aspect of the present invention includes a pump for delivering liquid fuel, a desulfurizer disposed downstream of the pump, and a sulfur desulfurizer disposed at a downstream side of the desulfurizer. A reformer for producing a reformed gas containing hydrogen by using a capillary tube through which the liquid fuel from which sulfur is removed is passed, and a liquid fuel from which sulfur is removed by a desulfurizer, disposed downstream of the capillary tube. And a fuel cell stack for generating power using reformed gas generated by the reformer.

In the fuel cell system according to the sixth aspect of the present invention, the capillary tube is disposed downstream of the desulfurizer. Therefore, by appropriately selecting the inner diameter and the length of the capillary tube, the pressure in the desulfurizer and the flow rate of the liquid fuel can be made a desired size without using an expensive pump. As a result, it is possible to realize the liquid feed at low flow rate easily and at low cost.

By the way, it is also possible to use an orifice, a needle valve, or the like instead of the capillary tube. However, since the flow path of the orifice portion is limited, the diameter of the orifice portion must be made extremely small in order to reduce the flow rate of the high-pressure liquid fuel discharged from the desulfurizer. Here, in the desulfurization unit, the liquid fuel is desulfurized by the desulfurization catalyst, but the desulfurization catalyst may be contained in the liquid fuel from which sulfur content is removed by the desulfurization unit. For this reason, when an orifice, a needle valve, etc. are used, the desulfurization catalyst which flowed out from the desulfurizer may be blocked by the flow path of an orifice part.

However, in the fuel cell system according to the sixth aspect of the present invention, since the capillary tube is used as described above, the inner diameter of the capillary tube can be increased to some extent depending on the length of the capillary tube. have. For this reason, clogging by a desulfurization catalyst is extremely unlikely to occur.

Preferably the pump is a constant pressure pump. In this way, management of the pressure in a desulfurizer becomes easy.

Preferably the inner diameter of the capillary tube is 0.1mm to 0.7mm. If the inner diameter of the capillary tube is less than 0.1 mm, the capillary tube tends to be clogged by the desulfurization catalyst. When the inner diameter of the capillary tube exceeds 0.7 mm, the total length of the required capillary tube is lengthened in order to supply liquid fuel at low flow rate while maintaining the inside of the desulfurizer at a high pressure, which tends to make compacting difficult. .

Preferably the capillary tube is spirally wound. This makes it difficult to swell even when the entire length of the capillary tube is long.

On the other hand, the reforming system according to the sixth aspect of the present invention is a pump for delivering liquid fuel, a desulfurizer disposed on the downstream side of the pump to remove sulfur from the liquid fuel, and disposed downstream of the desulfurizer. A capillary tube through which the liquid fuel from which sulfur is removed by gas flows and a liquid fuel from which sulfur is removed by a desulfurizer are generated on the downstream side of the capillary tube to generate reformed gas containing hydrogen. It is characterized by including a reformer.

In the reforming system according to the sixth aspect of the present invention, the capillary tube is disposed downstream of the desulfurizer. Therefore, by appropriately selecting the inner diameter and the length of the capillary tube, the pressure in the desulfurizer and the flow rate of the liquid fuel can be made a desired size without using an expensive pump. As a result, it is possible to realize the liquid feed at low flow rate easily and at low cost.

By the way, it is also possible to use an orifice, a needle valve, or the like instead of the capillary tube. However, since the flow path of the orifice portion is limited, the diameter of the orifice portion must be made extremely small in order to reduce the flow rate of the high-pressure liquid fuel discharged from the desulfurizer. Here, in the desulfurization unit, although the liquid fuel is desulfurized by the desulfurization catalyst, the desulfurization catalyst may be contained in the liquid fuel from which sulfur content is removed by the desulfurization unit. For this reason, when an orifice, a needle valve, etc. are used, the desulfurization catalyst which flowed out from the desulfurizer may be blocked by the flow path of an orifice part.

However, since the capillary tube is used in the reforming system according to the sixth aspect of the present invention as described above, the inner diameter of the capillary tube can be increased to some extent depending on the length of the capillary tube. . For this reason, clogging by a desulfurization catalyst is extremely unlikely to occur.

Preferably the pump is a constant pressure pump. In this way, management of the pressure in a desulfurizer becomes easy.

Preferably the inner diameter of the capillary tube is 0.1mm to 0.7mm. When the inner diameter of the capillary tube is less than 0.1 mm, the capillary tube tends to be clogged by the desulfurization catalyst. When the inner diameter of the capillary tube exceeds 0.7 mm, the total length of the required capillary tube is lengthened in order to supply liquid fuel at low flow rate while maintaining the inside of the desulfurizer at a high pressure, which tends to make compacting difficult. .

Preferably the capillary tube is spirally wound. This makes it difficult to swell even when the entire length of the capillary tube is long.

According to the sixth aspect of the present invention, it is possible to provide a fuel cell system and a reforming system capable of easily and inexpensively delivering liquid fuel at a low flow rate.

(1st embodiment)

Hereinafter, the fuel cell system 1 according to the first embodiment will be described in detail with reference to FIGS. 1 to 4.

1 is a configuration diagram of one embodiment of a fuel cell system according to the first embodiment. As shown in FIG. 1, the fuel cell system 1 includes a reforming apparatus 2 for generating reformed gas containing hydrogen and a desulfurization apparatus for removing sulfur content from liquid fuel for supplying the reforming apparatus 2 ( 3) and a fuel cell stack 4 for generating power using reformed gas generated by the reformer 2. For example, kerosene is used as the liquid fuel in view of the fuel cell system 1 being easily available and independently stored by being used as a power source for home use.

The reformer 2 has a reformer 5 for steam reforming liquid fuel to generate reformed gas, and a burner 6 for heating the reforming catalyst contained in the reformer 5. The burner 6 heats the reforming catalyst for promoting the steam reforming reaction, and supplies the reforming catalyst with the heat necessary to effectively exhibit the catalytic reaction. In the reformer 5, the liquid fuel introduced from the desulfurization apparatus 3 vaporizes into a source gas, and the reforming catalyst promotes the steam reforming reaction between the source gas and steam (water) to produce a hydrogen-rich reformed gas. do.

The fuel cell stack 4 is a solid polymer fuel cell stack configured by stacking a plurality of battery cells, and generates electricity using the reformed gas obtained by the reformer 2. Each battery cell has an anode, a cathode, and an ion exchange membrane of a polymer which is an electrolyte disposed between the anode and the cathode. In each battery cell, reformed gas is introduced into the anode, air is introduced into the cathode, and an electrochemical power generation reaction is performed.

FIG. 2 is a configuration diagram of a desulfurization apparatus included in the fuel cell system of FIG. 1. As shown in FIG. 2, the desulfurization apparatus 3 has a desulfurizer 7 containing a desulfurization catalyst 7a for removing sulfur content from liquid fuel for supply to the reformer 5. As shown in FIG. The desulfurization catalyst 7a is heated to a predetermined temperature by the heater 8 (heating means). On the upstream side of the desulfurizer 7, an inlet valve 9 (liquid fuel introduction means) for regulating the amount of liquid fuel introduced into the desulfurizer 7 is formed. On the upstream side of the inlet valve 9, a pump 11 (liquid fuel introduction means) for feeding liquid fuel into the desulfurizer 7 is formed. On the other hand, on the downstream side of the desulfurizer 7, an outlet valve 12 (liquid fuel derivation means) for adjusting the derivation amount of the liquid fuel from the desulfurizer 7 is formed.

Further, a desulfurizer 7 is provided with a thermometer 13 (temperature measuring means) for measuring the temperature of the liquid fuel in the desulfurizer 7. A pressure gauge 14 (pressure measuring means) for measuring the pressure of the liquid fuel in the desulfurizer 7 is formed between the desulfurizer 7 and the inlet valve 9. The control unit 15 (control means) is based on the temperature measured by the thermometer 13 and the pressure measured by the pressure gauge 14, the heater 8, the inlet valve 9, the pump 11 and the outlet valve. To control (12).

As shown in FIG. 1, one end of a liquid fuel distribution line 16 through which the sulfur content is removed is connected to the desulfurization apparatus 3, and the other end of the liquid fuel distribution line 16 is connected to a desulfurization apparatus ( It is connected to the side wall of the storage container 19 arrange | positioned above 3). The bottom wall of the storage container 19 has a liquid fuel distribution line 23 provided with a pump 22 for introducing a liquid fuel stored below in the storage container 19 to the reformer 5, and the liquid fuel. The liquid fuel distribution line 25 provided with the pump 24 for introducing into the burner 6 is connected. The burner 6 is also connected to an air distribution line 27 provided with a pump 26 for introducing air into the burner 6. Thus, by storing liquid fuel once in the storage container 19, supply of the liquid fuel to the reformer 5 by the pump 22, and the liquid fuel to the burner 6 by the pump 24 Supply can be stabilized.

In the fuel cell system 1 configured as described above, the liquid fuel is first introduced into the desulfurization unit 7 of the desulfurization apparatus 3, and sulfur content is removed by the desulfurization catalyst 7a in the state of high temperature and high pressure. The liquid fuel derived from the desulfurizer 7 is stored in the storage vessel 19 via the liquid fuel distribution line 16. The liquid fuel stored in the storage vessel 19 is introduced into the reformer 5 through the liquid fuel distribution line 23. At this time, the liquid fuel is introduced into the burner 6 through the liquid fuel distribution line 25, and air is introduced through the air distribution line 27. As a result, in the reformer 5, the reforming catalyst is heated by the burner 6 burning, and the liquid fuel is used to generate the reformed gas. The reformed gas generated in the reformer 5 is introduced into the fuel cell stack 4, and the reformed gas is used in the fuel cell stack 4 to generate power.

Next, the operation of the desulfurization apparatus 3 will be described. FIG. 3 is a graph showing the relationship between the temperature and pressure of the liquid fuel in the desulfurization apparatus in FIG. 2, and FIG. 4 is a flowchart showing the starting operation of the desulfurization apparatus of FIG. 2.

As shown in FIG. 3, the control part 15 memorize | stores the target value of the pressure of the liquid fuel in the desulfurizer 7 as a data table for every temperature of the liquid fuel in the desulfurizer 7. The target value of the pressure is set to be equal to or higher than the saturated vapor pressure of the liquid fuel at each temperature and equal to or less than the internal pressure of the desulfurizer 7. In other words, if the pressure of the liquid fuel in the desulfurizer 7 is maintained at the target value according to the temperature of the liquid fuel in the desulfurizer 7, the vaporization of the liquid fuel is prevented.

As shown in FIG. 4, when the starting operation of the desulfurization apparatus 3 is started, it is determined whether or not the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 is higher than A. 15) (Step S11). As a result, when the temperature of the liquid fuel in the desulfurizer 7 is lower than A, the controller 15 operates the heater 8 to heat the desulfurization catalyst 7a in the desulfurizer 7 (step S12). ), The process returns to the determination process of step S11.

As a result of the determination process of step S11, when the temperature of the liquid fuel in the desulfurizer 7 is higher than A, it is determined whether the pressure measured by the pressure gauge 14, that is, the pressure of the liquid fuel in the desulfurizer 7, is higher than X. The control part 15 determines whether it is (step S13). As a result, when the pressure of the liquid fuel in the desulfurizer 7 is lower than X, the control unit 15 operates the pump 11 to introduce the liquid fuel into the desulfurizer 7 and at the same time the inlet valve 9. Is opened (step S14), the heater 8 is stopped (step S15), and the process returns to the determination process of step S13.

As a result of the determination process of step S13, when the pressure of the liquid fuel in the desulfurizer 7 is higher than X, the control part 15 stops the pump 11 and closes the inlet valve 9 (step S16). Then, the control unit 15 determines whether the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 is higher than B (> A) (step S17). As a result, when the temperature of the liquid fuel in the desulfurization unit 7 is lower than B, the control unit 15 operates the heater 8 to heat the desulfurization catalyst 7a in the desulfurization unit 7 (step S18). ), The process returns to the determination process of step S17.

As a result of the determination process of step S17, when the temperature of the liquid fuel in the desulfurizer 7 is higher than B, the pressure measured by the pressure gauge 14, that is, the pressure of the liquid fuel in the desulfurizer 7 is Y (> X). ), The control unit 15 determines whether or not it is higher than () (step S19). As a result, when the pressure of the liquid fuel in the desulfurizer 7 is lower than Y, the control unit 15 operates the pump 11 to introduce the liquid fuel into the desulfurizer 7 and the inlet valve 9. Is opened (step S20), the heater 8 is stopped (step S21), and the process returns to the determination process of step S19.

As a result of the determination process of step S19, when the pressure of the liquid fuel in the desulfurizer 7 is higher than Y, the control unit 15 stops the pump 11 and closes the inlet valve 9 (step S22). Then, the controller 15 determines whether the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 is higher than C (> B) (step S23). As a result, when the temperature of the liquid fuel in the desulfurization unit 7 is lower than C, the control unit 15 operates the heater 8 to heat the desulfurization catalyst 7a in the desulfurization unit 7 (step S24). ), The process returns to the determination process of step S23.

As a result of the determination process of step S23, when the temperature of the liquid fuel in the desulfurizer 7 is higher than C, the pressure measured by the pressure gauge 14, that is, the pressure of the liquid fuel in the desulfurizer 7, is Z (> Y). ), The control unit 15 determines whether or not it is higher than () (step S25). As a result, when the pressure of the liquid fuel in the desulfurizer 7 is lower than Z, the control unit 15 operates the pump 11 to introduce the liquid fuel into the desulfurizer 7 and at the same time the inlet valve 9. Is opened (step S26), the heater 8 is stopped (step S27), and the process returns to the determination process of step S25.

As a result of the determination process of step S25, when the pressure of the liquid fuel in the desulfurizer 7 is higher than Z, the control unit 15 stops the pump 11 and closes the inlet valve 9 (step S28). Then, the controller 15 determines whether or not the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 is higher than D (> C) (step S29). As a result, when the temperature of the liquid fuel in the desulfurization unit 7 is lower than D, the control unit 15 operates the heater 8 to heat the desulfurization catalyst 7a in the desulfurization unit 7 (step S30). ), The process returns to the determination process of step S29.

As a result of the determination process in step S29, when the temperature of the liquid fuel in the desulfurization unit 7 is higher than D, the pump is desulfurized at that temperature to supply the reformer 2 with the liquid fuel from which sulfur is removed. The inlet valve 9 and the outlet valve 12 are opened at the same time as the operation of the 11 and the starting operation of the desulfurization apparatus 3 is completed.

As described above, in the desulfurization apparatus 3 of the fuel cell system 1, the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 becomes a predetermined temperature, and the pressure gauge 14 Control unit (i.e., the pressure of the liquid fuel in the desulfurizer 7) above the saturated vapor pressure of the liquid fuel at a predetermined temperature and a predetermined pressure (i.e., the target value) below the internal pressure of the desulfurizer at a predetermined temperature. 15 controls the heater 8, the inlet valve 9, the pump 11, and the outlet valve 12. This is the same not only at the start operation of the desulfurization apparatus 3 but also at the time of the normal operation and the stop operation of the desulfurization apparatus 3. Therefore, even if the temperature of the liquid fuel in the desulfurization unit 7 is increased, vaporization of the liquid fuel can be prevented, and as a result, efficient desulfurization and suppression of deterioration of the desulfurization catalyst 7a can be realized. .

In addition, when raising the pressure measured by the pressure gauge 14, the control part 15 operates the pump 11, opens the inlet valve 9, increases the introduction amount of the liquid fuel, and at the same time, the outlet valve 12 ) And reduce the output of liquid fuel. On the other hand, when reducing the pressure measured by the pressure gauge 14, the control part 15 stops the pump 11, closes the inlet valve 9, reduces the introduction amount of the liquid fuel, and at the same time, the outlet valve 12 ) To increase the output of liquid fuel. Thereby, the pressure measured by the pressure gauge 14, ie, the pressure of the liquid fuel in the desulfurizer 7, can be raised or lowered quickly and surely. In addition, "close the inlet valve 9 (or the outlet valve 12)" means not only when a valve is completely closed and flow volume becomes 0, but also when a valve is incompletely closed and a flow volume decreases.

The 1st aspect of this invention is not limited to embodiment mentioned above.

For example, the fuel cell stack 4 is not limited to the solid polymer fuel cell stack but may be a solid oxide fuel cell stack or the like.

The reformer 5 is not limited to steam reforming, but may be partial oxidation reforming or self thermal reforming. The reforming method by the reformer 5 depends on the characteristics of liquid fuel, such as gasoline, naphtha, diesel, methanol, ethanol, DME (dimethyl ether), and biofuel using biomass.

(2nd embodiment)

Hereinafter, the fuel cell system 1 according to the second embodiment will be described in detail with reference to FIGS. 5 to 8.

5 is a configuration diagram of one embodiment of a fuel cell system 1 according to the second embodiment. As shown in FIG. 5, the fuel cell system 1 includes a reforming apparatus 2 for generating reformed gas containing hydrogen and a desulfurization apparatus for removing sulfur content from liquid fuel for supplying the reforming apparatus 2 ( 3) and a fuel cell stack 4 for generating power using reformed gas generated by the reformer 2. For example, kerosene is used as the liquid fuel in view of the fuel cell system 1 being easily available and independently stored by being used as a power source for home use.

The reformer 2 has a reformer 5 for steam reforming liquid fuel to generate reformed gas, and a burner 6 for heating the reforming catalyst contained in the reformer 5. The burner 6 heats the reforming catalyst for promoting the steam reforming reaction, and supplies the reforming catalyst with the heat necessary to effectively exhibit the catalytic reaction. In the reformer 5, the liquid fuel introduced from the desulfurization apparatus 3 vaporizes into a source gas, and the reforming catalyst promotes the steam reforming reaction between the source gas and steam (water), and generates a reformed gas rich in hydrogen. do.

The fuel cell stack 4 is a solid polymer fuel cell stack configured by stacking a plurality of battery cells, and generates electricity using the reformed gas obtained by the reformer 2. Each battery cell has an anode, a cathode, and an ion exchange membrane of a polymer which is an electrolyte disposed between the anode and the cathode. In each battery cell, reformed gas is introduced into the anode, air is introduced into the cathode, and an electrochemical power generation reaction is performed.

6 is a configuration diagram of a desulfurization apparatus included in the fuel cell system of FIG. 5. As shown in FIG. 6, the desulfurization apparatus 3 has a desulfurizer 7 containing a desulfurization catalyst 7a for removing sulfur content from the liquid fuel for supplying to the reformer 5. The desulfurization catalyst 7a is heated to a predetermined temperature by the heater 8 (heating means). On the upstream side of the desulfurizer 7, an inlet valve 9 (liquid fuel introduction means) for regulating the amount of liquid fuel introduced into the desulfurizer 7 is formed. On the upstream side of the inlet valve 9, a pump 11 (liquid fuel introduction means) for feeding liquid fuel into the desulfurizer 7 is formed. On the other hand, on the downstream side of the desulfurizer 7, an outlet valve 12 (liquid fuel derivation means) for adjusting the derivation amount of the liquid fuel from the desulfurizer 7 is formed.

Further, a desulfurizer 7 is provided with a thermometer 13 (temperature measuring means) for measuring the temperature of the liquid fuel in the desulfurizer 7. A pressure gauge 14 (pressure measuring means) for measuring the pressure of the liquid fuel in the desulfurizer 7 is formed between the desulfurizer 7 and the inlet valve 9. The control unit 15 (control means) controls the heater 8, the inlet valve 9, the pump 11 and the outlet valve 12 in accordance with the signal when a predetermined signal is output. The predetermined signal is a start signal, a stop signal, a pause signal, and an operation resume signal.

As shown in FIG. 5, one end of a liquid fuel distribution line 16 through which the sulfur fuel has been removed is connected to the desulfurization apparatus 3, and the other end of the liquid fuel distribution line 16 is a desulfurization apparatus ( It is connected to the side wall of the storage container 19 arrange | positioned above 3). The storage container 19 is provided with a leveler 20 (storage amount measuring means) for measuring the amount of storage. When the storage amount in the storage container 19 reaches the first storage amount, the leveler 20 outputs a pause signal to the control unit 15, and the storage amount in the storage container 19 is lower than the first storage amount. When the reduction is reached due to the storage amount, the operation resume signal is output to the control unit 15.

The bottom wall of the storage container 19 also has a liquid fuel distribution line 23 provided with a pump 22 for introducing a liquid fuel stored below in the storage container 19 to the reformer 5, and the same liquid. The liquid fuel distribution line 25 provided with the pump 24 for introducing the fuel into the burner 6 is connected. The burner 6 is also connected to an air distribution line 27 provided with a pump 26 for introducing air into the burner 6. In this way, the liquid fuel is once stored in the storage container 19, so that the liquid fuel is supplied to the reformer 5 by the pump 22 and the liquid fuel to the burner 6 by the pump 24. Supply can be stabilized.

In the fuel cell system 1 configured as described above, the liquid fuel is first introduced into the desulfurization unit 7 of the desulfurization apparatus 3, and sulfur content is removed by the desulfurization catalyst 7a in the state of high temperature and high pressure. The liquid fuel derived from the desulfurizer 7 is stored in the storage vessel 19 via the liquid fuel distribution line 16. The liquid fuel stored in the storage vessel 19 is introduced into the reformer 5 through the liquid fuel distribution line 23. At this time, the liquid fuel is introduced into the burner 6 through the liquid fuel distribution line 25, and air is introduced through the air distribution line 27. As a result, in the reformer 5, the reforming catalyst is heated by the burner 6 burning, and the liquid fuel is used to generate the reformed gas. The reformed gas generated in the reformer 5 is introduced into the fuel cell stack 4, and the reformed gas is used in the fuel cell stack 4 to generate power.

Next, the operation of the desulfurization apparatus 3 will be described. FIG. 7 is a diagram showing an example of the relationship between the operating state and the set temperature in the desulfurization apparatus of FIG. 6, and FIG. 8 is a flowchart showing the operation of the desulfurization apparatus of FIG. 6.

As shown in FIG. 7, the control part 15 memorize | stores the target value of the temperature in the desulfurizer 7 as a data table for every operation state. The target value of the temperature is, for example, 190 deg. C to 210 deg. C (predetermined desulfurization temperature: temperature A which can promote the catalytic reaction of the desulfurization catalyst 7a) during normal operation, and 180 deg. C to 190 deg. Temperature B). The temperature B (predetermined temperature) at the time of temporary stop is set higher than the temperature (5 degreeC-35 degreeC) at the time of stop, and lower than the temperature A at the time of normal operation.

As shown in FIG. 8, in the normal operation in which the desulfurization apparatus 3 is activated, the control part 15 determines whether the pause signal was input from the leveler 20 (step S11). As a result, when the pause signal is input, the control unit 15 stops the pump 11 in order to stop the introduction of the liquid fuel into the desulfurizer 7 and at the same time the inlet valve 9 and the outlet valve ( 12) (step S12). And the control part 15 controls the heater 8 so that the temperature of the liquid fuel in the desulfurizer 7 may become temperature B (step S13).

After the process of step S13, the control part 15 determines whether the operation restart signal was input from the leveler 20 (step S14). As a result, when the operation resume signal is input, the control unit 15 controls the heater 8 so that the temperature of the liquid fuel in the desulfurizer 7 becomes the temperature A (step S15). Then, in order to desulfurize at the temperature A and supply the liquid fuel from which the sulfur content has been removed to the reformer 2 again, the pump 11 is operated and the inlet valve 9 and the outlet valve 12 are opened ( The process returns to the determination process of step S16) and step S11. On the other hand, in step S17, when the operation resume signal is not input, the same process is repeated until an operation resume signal is input.

On the other hand, when the pause signal is not input as a result of the determination process of step S11, the control part 15 determines whether the stop signal was input (step S17). As a result, when a stop signal is input, the control part 15 stops the pump 11, closes the inlet valve 9 and the outlet valve 12 (step S18), and stops the heater 8 again. (Step S19), operation of the desulfurization apparatus 3 is complete | finished. On the other hand, when no stop signal is input, the process returns to the determination process of step S11. The stop signal is input to the controller 15 by pressing a button, for example, for stopping the operation of the desulfurization apparatus 3.

As described above, in the desulfurization apparatus 3 of the fuel cell system 1, when a pause signal is input from the leveler 20, the liquid fuel from the desulfurizer 7 to the storage vessel 19 is discharged. The control unit 15 controls the inlet valve 9, the pump 11 and the outlet valve 12 so that the supply is stopped. At this time, the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 is maintained at a predetermined temperature B (i.e., a target value) that is higher than normal temperature and lower than the temperature A during normal operation. The control unit 15 controls the heater 8. As a result, compared with the case where the desulfurization apparatus 3 is stopped and the temperature is lowered to room temperature, the time until heating to the temperature A during normal operation, that is, the predetermined desulfurization temperature is shortened. The time can be shortened.

In addition, as shown in FIG. 7, the temperature B at the time of pausing is made lower than the temperature A at the time of normal operation, and reduction of energy consumption is attained. In addition, since temperature B is not lowered to normal temperature at the time of temporary stop, deterioration of the desulfurization catalyst 7a resulting from the temperature difference with normal operation can be prevented.

Moreover, the storage container 19 which stores a liquid fuel once is provided, and when the storage amount of the storage container 19 reaches the 1st storage amount, the leveler 20 outputs a pause signal to the control part 15. As shown in FIG. On the other hand, when the amount of storage of the storage container 19 decreases to reach the second amount of storage lower than the first amount of storage, the leveler 20 outputs an operation resume signal to the control unit 15. Thereby, for example, damage to the storage container 19 due to over storage amount can be prevented. In addition, when it reaches and decreases by the 2nd storage amount lower than a 1st storage amount, an operation resume signal is output and operation | movement of the desulfurization apparatus 3 is resumed, and work efficiency can be aimed at.

The second aspect of the present invention is not limited to the above-described embodiment.

For example, when the pause signal is input, only the inlet valve 9 may be closed without closing both the inlet valve 9 and the outlet valve 12.

The pause signal and the operation resume signal may not be input from the leveler 20 but may be input by, for example, pressing a button.

The fuel cell stack 4 is not limited to a solid polymer fuel cell stack, and may be a solid oxide fuel cell stack or the like.

The reformer 5 is not limited to steam reforming, but may be partial oxidation reforming or self thermal reforming. The reforming method by the reformer 5 depends on the characteristics of liquid fuel, such as gasoline, naphtha, diesel, methanol, ethanol, DME (dimethyl ether), and biofuel using biomass.

(Third embodiment)

Hereinafter, the fuel cell system 1 according to the third embodiment will be described in detail with reference to FIGS. 9 to 12.

9 is a configuration diagram of one embodiment of a fuel cell system according to the third embodiment. As shown in FIG. 9, the fuel cell system 1 includes a reforming apparatus 2 for generating reformed gas containing hydrogen and a desulfurization apparatus for removing sulfur content from liquid fuel for supplying the reforming apparatus 2 ( 3) and a fuel cell stack 4 for generating power using reformed gas generated by the reformer 2. For example, kerosene is used as the liquid fuel in view of the fuel cell system 1 being easily available and independently stored by being used as a power source for home use.

The reformer 2 has a reformer 5 for steam reforming liquid fuel to generate reformed gas, and a burner 6 for heating the reforming catalyst contained in the reformer 5. The burner 6 heats the reforming catalyst for promoting the steam reforming reaction, and supplies the reforming catalyst with the heat necessary to effectively exhibit the catalytic reaction. In the reformer 5, the liquid fuel introduced from the desulfurization apparatus 3 vaporizes into a source gas, and the reforming catalyst promotes the steam reforming reaction between the source gas and steam (water), and generates a reformed gas rich in hydrogen. do.

The fuel cell stack 4 is a solid polymer fuel cell stack configured by stacking a plurality of battery cells, and generates electricity using the reformed gas obtained by the reformer 2. Each battery cell has an anode, a cathode, and an ion exchange membrane of a polymer which is an electrolyte disposed between the anode and the cathode. In each battery cell, reformed gas is introduced into the anode, air is introduced into the cathode, and an electrochemical power generation reaction is performed.

FIG. 10 is a configuration diagram of a desulfurization apparatus included in the fuel cell system of FIG. 9. As shown in FIG. 10, the desulfurization apparatus 3 has a desulfurizer 7 containing a desulfurization catalyst 7a for removing sulfur content from the liquid fuel for supplying to the reformer 5. The desulfurization catalyst 7a is heated to a predetermined temperature by the heater 8 (heating means). On the upstream side of the desulfurizer 7, an inlet valve 9 (liquid fuel introduction means) for regulating the amount of liquid fuel introduced into the desulfurizer 7 is formed. On the upstream side of the inlet valve 9, a pump 11 (liquid fuel introduction means) for feeding liquid fuel into the desulfurizer 7 is formed. On the other hand, on the downstream side of the desulfurizer 7, an outlet valve 12 (liquid fuel derivation means) for adjusting the derivation amount of the liquid fuel from the desulfurizer 7 is formed.

Further, a desulfurizer 7 is provided with a thermometer 13 (temperature measuring means) for measuring the temperature of the liquid fuel in the desulfurizer 7. A pressure gauge 14 (pressure measuring means) for measuring the pressure of the liquid fuel in the desulfurizer 7 is formed between the desulfurizer 7 and the inlet valve 9. The control unit 15 (control means) is based on the temperature measured by the thermometer 13 and the pressure measured by the pressure gauge 14, the heater 8, the inlet valve 9, the pump 11 and the outlet valve ( 12).

As shown in FIG. 9, one end of the liquid fuel distribution line 16 through which the sulfur fuel is removed is connected to the desulfurization apparatus 3, and the other end of the liquid fuel distribution line 16 is connected to the desulfurization apparatus ( It is connected to the side wall of the storage container 19 arrange | positioned above 3). The bottom wall of the storage container 19 has a liquid fuel distribution line 23 provided with a pump 22 for introducing a liquid fuel stored below in the storage container 19 to the reformer 5, and the liquid fuel. The liquid fuel distribution line 25 provided with the pump 24 for introducing into the burner 6 is connected. The burner 6 is also connected with an air distribution line 27 provided with a pump 26 for introducing air into the burner 6. Thus, by storing liquid fuel once in the storage container 19, supply of the liquid fuel to the reformer 5 by the pump 22, and the liquid fuel to the burner 6 by the pump 24 Supply can be stabilized.

In the fuel cell system 1 configured as described above, the liquid fuel is first introduced into the desulfurization unit 7 of the desulfurization apparatus 3, and sulfur content is removed by the desulfurization catalyst 7a in the state of high temperature and high pressure. The liquid fuel derived from the desulfurizer 7 is stored in the storage vessel 19 via the liquid fuel distribution line 16. The liquid fuel stored in the storage vessel 19 is introduced into the reformer 5 through the liquid fuel distribution line 23. At this time, the liquid fuel is introduced into the burner 6 through the liquid fuel distribution line 25, and air is introduced through the air distribution line 27. As a result, in the reformer 5, the reforming catalyst is heated by the burner 6 burning, and the liquid fuel is used to generate the reformed gas. The reformed gas generated in the reformer 5 is introduced into the fuel cell stack 4, and the reformed gas is used in the fuel cell stack 4 to generate power.

Next, the operation of the desulfurization apparatus 3 will be described. FIG. 11 is a table showing a relationship between temperature and pressure at the time of stop of operation in the desulfurization apparatus of FIG. 10, and FIG. 12 is a flowchart showing the operation of the desulfurization apparatus of FIG. 10.

As shown in FIG. 11, the control part 15 memorize | stores the lower limit (target value) of the pressure in the desulfurizer 7 as a data table for every temperature range at the time of stop. The lower limit of the pressure is, for example, 200 kPa at 150 ° C or higher, and 100 kPa at 100 ° C to 150 ° C. For example, it is 5 kPa at 100 degrees C or less. The pressure at 100 degrees C (predetermined temperature) lower than the temperature at the time of normal operation is set so that it may become predetermined pressure which is a positive pressure (negative pressure or more).

As shown in FIG. 12, when the stop operation of the desulfurization apparatus 3 is started, the control unit 15 stops the pump 11 to stop the introduction of liquid fuel into the desulfurizer 7 and at the same time the inlet valve ( 9) and the outlet valve 12 are closed (step S11), and the heater 8 is stopped (step S12).

After the process of step S12, the control part 15 determines whether the pressure measured by the pressure gauge 14, ie, the pressure of the liquid fuel in the desulfurizer 7, is higher than the pressure A (for example, 5 kPa) (step S13). As a result, when the pressure of the liquid fuel in the desulfurizer 7 is higher than the pressure A, the process returns to the determination process of step S13. On the other hand, when the pressure of the liquid fuel in the desulfurizer 7 is lower than the pressure A, the control unit 15 operates the pump 11 to introduce the liquid fuel into the desulfurizer 7 and the inlet valve 9. (Step S14).

After the process of step S14, the control part 15 determines whether the pressure measured by the pressure gauge 14, ie, the pressure of the liquid fuel in the desulfurizer 7, is higher than the pressure B (for example, 40 kPa) (step S15). As a result, when the pressure of the liquid fuel in the desulfurizer 7 is higher than the pressure B, the control unit 15 stops the pump 11 and stops the inlet in order to stop the introduction of the liquid fuel into the desulfurizer 7. The valve 9 is closed (step S16), and the process returns to the determination process of step S13. On the other hand, when the pressure of the liquid fuel in the desulfurizer 7 is higher than the pressure B, the process returns to the determination process of step S15.

As described above, in the desulfurization apparatus 3 of the fuel cell system 1, the temperature measured by the thermometer 13, that is, the temperature of the liquid fuel in the desulfurizer 7 is lower than the temperature during normal operation. When the temperature is below the temperature, the controller 15 controls the inlet valve 9 and the pump 11 so that the pressure measured by the pressure gauge 14, that is, the pressure of the liquid fuel in the desulfurizer 7 becomes a predetermined pressure which is a constant pressure. ) And the outlet valve 12. Therefore, even when the pressure is reduced due to the drop in the temperature of the liquid fuel, for example, at the time of stopping operation, a predetermined pressure is maintained, so that the vaporization of the liquid fuel or the desulfurizer ( It is possible to prevent adverse effects on the desulfurizer 7 such as breakage of 7).

In addition, when raising the pressure measured by the pressure gauge 14, the control part 15 operates the pump 11, opens the inlet valve 9, increases the introduction amount of the liquid fuel, and at the same time, the outlet valve 12 ) And reduce the output of liquid fuel. On the other hand, when reducing the pressure measured by the pressure gauge 14, the control part 15 stops the pump 11, closes the inlet valve 9, reduces the introduction amount of the liquid fuel, and at the same time, the outlet valve 12 ) To increase the output of liquid fuel. Thereby, the pressure measured by the pressure gauge 14, ie, the pressure of the liquid fuel in the desulfurizer 7, can be raised or lowered quickly and surely. In addition, "close the inlet valve 9 (or the outlet valve 12)" means not only when a valve is completely closed and flow volume becomes zero, but also when a valve is incompletely closed and a flow volume decreases.

The third aspect of the present invention is not limited to the above-described embodiment.

For example, the fuel cell stack 4 is not limited to the solid polymer fuel cell stack but may be a solid oxide fuel cell stack or the like.

The reformer 5 is not limited to steam reforming, but may be partial oxidation reforming or self thermal reforming. The reforming method by the reformer 5 depends on the characteristics of liquid fuel, such as gasoline, naphtha, diesel, methanol, ethanol, DME (dimethyl ether), and biofuel using biomass.

(4th Embodiment)

Hereinafter, the fuel cell system 1 according to the fourth embodiment will be described in detail with reference to FIGS. 13 and 14.

13 is a configuration diagram of one embodiment of a fuel cell system according to the fourth embodiment. As shown in FIG. 13, the fuel cell system 1 includes a reforming apparatus 2 for generating reformed gas containing hydrogen and a desulfurization apparatus for removing sulfur content from liquid fuel for supplying the reforming apparatus 2 ( 3) and a fuel cell stack 4 for generating power using reformed gas generated by the reformer 2. For example, kerosene is used as the liquid fuel in view of the fuel cell system 1 being easily available and independently stored by being used as a power source for home use.

The reformer 2 has a reformer 5 for steam reforming liquid fuel to generate reformed gas, and a burner 6 for heating the reforming catalyst contained in the reformer 5. The burner 6 heats the reforming catalyst for promoting the steam reforming reaction, and supplies the reforming catalyst with the heat necessary to effectively exhibit the catalytic reaction. In the reformer 5, the liquid fuel introduced from the desulfurization apparatus 3 vaporizes into a source gas, and the reforming catalyst promotes the steam reforming reaction between the source gas and steam (water), and generates a reformed gas rich in hydrogen. do.

The fuel cell stack 4 is a solid polymer fuel cell stack configured by stacking a plurality of battery cells, and generates electricity using the reformed gas obtained by the reformer 2. Each battery cell has an anode, a cathode, and an ion exchange membrane of a polymer which is an electrolyte disposed between the anode and the cathode. In each battery cell, reformed gas is introduced into the anode, air is introduced into the cathode, and an electrochemical power generation reaction is performed.

The desulfurization apparatus 3 stores a desulfurizer 8 for removing sulfur content from the liquid fuel introduced by the pump 7 and a liquid fuel and gas (methane gas or hydrogen gas, etc.) discharged from the desulfurizer 8. It has the gas-liquid separation container 9 to make. In the gas-liquid separation container 9, a float switch 11 for detecting the liquid level of the liquid fuel is provided for detecting the amount of gas. The gas-liquid separation vessel 9 is disposed above the desulfurizer 8, and one end of the liquid fuel and gas distribution line 12 through which the liquid fuel and gas flow is connected to the bottom wall of the desulfurizer 8, The other end is connected to the bottom wall of the gas-liquid separation container 9. Thereby, the gas discharged | emitted from the desulfurizer 8 can be introduce | transduced certainly in the gas-liquid separation container 9.

One end of the gas discharge line 13 for discharging the gas stored above in the gas-liquid separation vessel 9 from the gas-liquid separation vessel 9 is connected to the ceiling wall of the gas-liquid separation vessel 9. The other end of the gas discharge line 13 is connected to a burner 6 for heating the reforming catalyst of the reformer 5. The gas discharge line 13 is provided with an solenoid valve 14 (opening and closing valve) for opening and closing the flow of gas. The solenoid valve 14 cooperates with the gas-liquid separation container 9 to constitute a degasser D for removing gas from the liquid fuel. Further, a capillary 15 (throttle) is formed on the downstream side of the solenoid valve 14 in the gas discharge line 13 to inhibit the flow of gas. Moreover, the air distribution line 17 in which the pump 16 for introducing air to the burner 6 is formed in the downstream of the capillary 15 in the gas discharge line 13 is connected.

On the other hand, one end of the liquid fuel discharge line 18 for discharging the liquid fuel stored below in the gas-liquid separation vessel 9 from the gas-liquid separation vessel 9 is connected to the bottom wall of the gas-liquid separation vessel 9. . The other end of the liquid fuel discharge line 18 is connected to the side wall of the storage container 19 disposed above the gas-liquid separation container 9. The liquid fuel discharge line 18 is provided with a capillary 21 that inhibits the flow of the liquid fuel.

The bottom wall of the storage container 19 has a liquid fuel distribution line 23 provided with a pump 22 for introducing a liquid fuel stored below in the storage container 19 to the reformer 5, and the liquid fuel. The liquid fuel distribution line 25 provided with the pump 24 for introducing into the burner 6 is connected. Thus, by storing liquid fuel once in the storage container 19, supply of the liquid fuel to the reformer 5 by the pump 22, and the liquid fuel to the burner 6 by the pump 24 Supply can be stabilized.

In the fuel cell system 1 configured as described above, the liquid fuel is first introduced into the desulfurization unit 8, and in the desulfurization unit 8, sulfur content is removed from the liquid fuel by the desulfurization catalyst in a state of high temperature and high pressure. The liquid fuel and gas discharged from the desulfurizer 8 are stored in the gas-liquid separation vessel 9, and the liquid fuel is reformer through the liquid fuel discharge line 18, the storage vessel 19, and the liquid fuel distribution line 23. It is introduced in (5). At this time, the liquid fuel is introduced into the burner 6 through the liquid fuel discharge line 18, the storage vessel 19, and the liquid fuel distribution line 25, and air is introduced through the air distribution line 17. . As a result, in the reformer 5, the reforming catalyst is heated by the burner 6 burning, and the liquid fuel is used to generate the reformed gas. The reformed gas generated in the reformer 5 is introduced into the fuel cell stack 4, and the reformed gas is used in the fuel cell stack 4 to generate power.

On the other hand, the gas stored in the gas-liquid separation vessel 9 is introduced into the burner 6 through the gas discharge line 13 and used together with the liquid fuel as the fuel of the burner 6. In this manner, the gas discharged from the desulfurizer 8 together with the liquid fuel can be effectively used as the fuel of the burner 6. In the case where the flow of gas is closed, the solenoid valve 14 is divided into a plurality of times when the amount of gas in the gas-liquid separation vessel 9 detected by the float switch 11 exceeds a predetermined amount. Open the distribution of gas.

As described above, in the desulfurization apparatus 3 of the fuel cell system 1, the gas discharged together with the liquid fuel from the desulfurizer 8 is separated from the liquid fuel in the gas-liquid separation vessel 9, and the gas discharge line ( 13 is discharged from the gas-liquid separation vessel 9. For this reason, the liquid fuel mixed with gas is prevented from being supplied to the rear end of the desulfurization apparatus 3 (for example, the pumps 22, 24, the reformer 5, etc.). In the gas discharge line 13, a capillary 15 is formed on the downstream side of the solenoid valve 14 that opens and closes the flow of the gas. For this reason, even if the flow of gas is opened by the solenoid valve 14 in order to discharge gas from the gas-liquid separation container 9 through the gas discharge line 13, the desulfurizer 8 is carried out by the capillary 15. The fall of the internal pressure is suppressed and the state of high pressure is maintained. Therefore, according to the desulfurization apparatus 3 of the fuel cell system 1, it becomes possible to reliably remove sulfur content from liquid fuel, preventing the bad influence to a rear end.

In addition, the capillary 21 formed in the liquid fuel discharge line 18 also suppresses a decrease in the pressure in the desulfurizer 8 and maintains a high pressure state. In other words, since the pressure in the desulfurizer 8 is kept constant by the capillaries 15 and 21, it is possible to use a constant pressure pump for the pump 7.

In the case where the flow of gas is closed, the solenoid valve 14 is divided into a plurality of times when the amount of gas in the gas-liquid separation vessel 9 detected by the float switch 11 exceeds a predetermined amount. Open the distribution of gas. Thereby, the fall of the pressure in the desulfurizer 8 at the time of opening of the gas by the solenoid valve 14 in order to discharge gas from the gas-liquid separation container 9 via the gas discharge line 13 is suppressed. It can be suppressed more certainly.

FIG. 14 is a graph showing the relationship between the pressure of the float switch, the solenoid valve and the desulfurizer in the fuel cell system of FIG. As shown in FIG. 14, while the float switch 11 is turned ON, that is, while the amount of gas in the gas-liquid separation vessel 9 exceeds a predetermined amount (here, 15 seconds), a predetermined interval The magnetic valve 14 is opened for a short time (here 200 m seconds) at a plurality of times (here, three times here) at an interval of 5 seconds here. As a result, the pressure at the inlet and the outlet of the desulfurizer 8 is maintained at a high pressure with only a slight pressure drop (here, a pressure drop of 10 to 20 kPa).

The fourth aspect of the present invention is not limited to the above-described embodiment.

For example, the fuel cell stack 4 is not limited to the solid polymer fuel cell stack but may be a solid oxide fuel cell stack or the like.

The reformer 5 is not limited to steam reforming, but may be partial oxidation reforming or self thermal reforming. The reforming method by the reformer 5 depends on the characteristics of liquid fuel, such as gasoline, naphtha, diesel, methanol, ethanol, DME (dimethyl ether), and biofuel using biomass.

In addition, the throttle which prevents the flow of gas in the gas discharge line 13 and the flow of the liquid fuel in the liquid fuel discharge line 18 is not limited to the capillaries 15 and 21, An orifice, a needle valve, etc. may be sufficient.

(5th Embodiment)

Hereinafter, the fuel cell system 1 according to the fifth embodiment will be described in detail with reference to FIGS. 15 to 21.

As shown in FIG. 15, the fuel cell system 1 reforms a desulfurization apparatus 2 for removing sulfur content from the supplied raw fuel and a liquid fuel from which sulfur content has been removed by the desulfurization apparatus 2 to reform the reformed gas. A reformer 3 to be produced and a fuel cell stack 4 for generating power using reformed gas generated by the reformer 3 are provided. The fuel cell system 1 is used as a source of electric power for home use, and thus kerosene is used as a raw fuel from the viewpoint of being easily available and independently stored.

The reformer 3 has a reformer 5 for steam reforming the liquid fuel to produce a hydrogen-rich reformed gas, and a burner 6 for heating the reforming catalyst contained in the reformer 5. The burner 6 heats the reforming catalyst for promoting the steam reforming reaction, and supplies the reforming catalyst with the heat necessary to effectively exhibit the catalytic reaction. The fuel of the burner 6 is mainly raw fuel and oxygen. For this reason, the burner 6 is connected with the fuel line 25 for supplying raw fuel, and the air distribution line 17 connected with the blower 16 for introducing air into the burner 6. In the reformer 5, the liquid fuel desulfurized by the desulfurization apparatus 2 vaporizes into a source gas, and a reforming catalyst promotes the steam reforming reaction between the source gas and steam (water), thereby reforming hydrogen-rich reformed gas. Is generated.

The fuel cell stack 4 is a solid polymer fuel cell stack configured by stacking a plurality of battery cells, and generates electricity using reformed gas obtained from the reformer 3. Each battery cell has an anode, a cathode, and an ion exchange membrane of a polymer which is an electrolyte disposed between the anode and the cathode. In each battery cell, reformed gas is introduced into the anode, air is introduced into the cathode, and an electrochemical power generation reaction is performed.

The desulfurization apparatus 2 includes a desulfurizer 8 for removing sulfur content from the raw fuel introduced by the constant pressure pump 7, and liquid fuel and gas (methane gas or hydrogen gas, etc.) discharged from the desulfurizer 8; It has the gas-liquid separation container 9 for separating. The raw fuel contains sulfur, such as sulfur or sulfur compounds of about 80 ppm or less. The desulfurizer 8 removes sulfur content from the raw fuel to produce a liquid fuel having a sulfur concentration of about 50 ppb or less. The desulfurizer 8 is maintained at a high pressure by the structure described below, and the desulfurization reaction proceeds at a high pressure.

In the gas-liquid separation container 9, a float switch 11 for detecting the liquid level of the liquid fuel is provided for detecting the amount of gas. The gas-liquid separation vessel 9 is disposed above the desulfurizer 8, and one end of the liquid fuel and gas distribution line 12 through which the liquid fuel and gas flow is connected to the bottom wall of the desulfurizer 8, The other end is connected to the bottom wall of the gas-liquid separation container 9. Thereby, the gas discharged | emitted from the desulfurizer 8 can be introduce | transduced certainly in the gas-liquid separation container 9. The volume of this gas-liquid separation container 9 is about 100 cc. Although not shown, a filter is formed in the liquid fuel and gas distribution line 12 for the purpose of removing the desulfurization catalyst contained in the liquid fuel from which sulfur content has been removed by the desulfurization unit 8. In the fifth embodiment, for example, a filter having a scale interval of about 0.026 mm can be used.

One end of the gas discharge line 13 for discharging the gas stored above in the gas-liquid separation vessel 9 from the gas-liquid separation vessel 9 is connected to the ceiling wall of the gas-liquid separation vessel 9. The gas discharge line 13 is provided with a solenoid valve 14 for opening and closing the flow of gas. The solenoid valve 14 cooperates with the gas-liquid separation container 9 to constitute a degas D that removes gas from the liquid fuel. Moreover, the capillary tube 15 which prevents gas flow is provided in the downstream of the solenoid valve 14 in the gas discharge line 13. For this reason, even if the flow of gas is opened by the on / off valve for discharging the gas from the gas-liquid separation vessel through the gas discharge line, the drop in the pressure in the desulfurizer 8 and the gas-liquid separation vessel 9 is suppressed by the throttle. . Moreover, the downstream side of the capillary tube 15 in the gas discharge line 13 is connected to the air distribution line 17.

On the other hand, one end of the liquid fuel discharge line 18 for discharging the liquid fuel stored below in the gas-liquid separation vessel 9 from the gas-liquid separation vessel 9 is connected to the bottom wall of the gas-liquid separation vessel 9. . The other end of the liquid fuel discharge line 18 is connected to the bottom wall of the oil storage tank 19 disposed above the gas-liquid separation vessel 9. The liquid fuel discharge line 18 is provided with a capillary tube 21 that inhibits the flow of the liquid fuel.

Here, the capillary tube 21 is a spirally wound microfine tube. Since the capillary tube 21 throttles the flow rate of the liquid fuel downstream of the desulfurizer 8, the flow rate in the desulfurizer 8 can be made low. On the other hand, since the liquid fuel is pumped into the desulfurizer 8 by the constant pressure pump 7, the desulfurizer 8 is pressurized, and the desulfurization reaction is performed under high pressure. For example, in the case of a 1 kW fuel cell system, the flow rate of the liquid fuel (liquid fuel) becomes 10 g / min or less, and the pressure in the flow path from the constant pressure pump 7 to the capillary tube 21 is 0.1 MPa. The inner diameter of the capillary tube 21 and the diameter at the time of winding are set so that it may become a larger high pressure of 1.0 Mpa or less. Specifically, the capillary tube 21 preferably has an inner diameter of about 0.1 mm to 0.5 mm, and is preferably wound up so that the diameter of the spiral is about 10 mm to 100 mm.

As mentioned above, although the filter is provided in the liquid fuel and gas distribution line 12, since the desulfurization catalyst of the particle diameter smaller than the snow passes through a filter, the inner diameter of the capillary tube 21 is less than 0.1 mm. On the back side, the capillary tube 21 tends to be clogged by the desulfurization catalyst. On the other hand, when the inner diameter of the capillary tube 21 exceeds 0.5 mm, there exists a tendency for the liquid fuel delivery at low flow volume to become difficult. Moreover, the pressure loss can be adjusted according to the magnitude | size of the diameter when the capillary tube 21 is wound up.

A flowmeter 26 is formed downstream of the capillary tube 21 in the liquid fuel discharge line 18. The flowmeter 26 measures the flow rate of the liquid fuel flowing out of the capillary tube 21. That is, the flowmeter 26 measures the production rate of the liquid fuel produced by the desulfurization reaction in the desulfurizer 8. Since this flowmeter 26 is formed downstream of the gas-liquid separation container 9, the flow rate of the liquid fuel which the gas isolate | separated and flowed in is measured, and a flow volume can be measured stably.

The desulfurization apparatus 2 is further provided with a storage tank 19 which is connected to the liquid fuel discharge line 18 and disposed downstream from the flowmeter 26. A liquid fuel distribution line 23 is connected to the ceiling wall of the oil storage tank 19, and a pump for delivering the liquid fuel stored in the oil storage tank 19 to the reformer 5 is connected to the liquid fuel distribution line 23. 24 is provided. In addition, a gas discharge line 27 for discharging the gas stored above the inside of the storage tank 19 is connected to the ceiling wall of the storage tank 19.

Next, with reference to FIG. 16 and FIG. 17, the oil storage tank 19 is demonstrated in more detail. The oil storage tank 19 is a hollow rectangular parallelepiped container constituted by the ceiling wall 19a, the bottom wall 19b, and the side wall 19c, and has a volume of about 200 cc. The oil storage tank 19 is connected to the inlet pipe 31 which connects the capillary tube 21 and the oil storage tank 19 in the liquid fuel discharge line 18. The inflow pipe 31 penetrates the bottom wall 19b, and the inflow port 31a located in the oil storage tank 19 of the inflow pipe 31 is opened upward. High pressure liquid fuel flows into the oil storage tank 19 from this inlet port 31a.

A gas extraction hole 32 is formed in the ceiling wall 19a of the oil storage tank 19, and one end of the gas extraction pipe 33 constituting the gas discharge line 27 is inserted into the gas extraction hole 32. . Since the other end of the gas extraction pipe 33 is open to the atmosphere, the pressure in the oil storage tank 19 is maintained at atmospheric pressure, and the gas contained in the liquid fuel is separated from the introduced liquid fuel. The gas separated from the liquid fuel in the oil storage tank 19 flows into the gas extraction pipe 33 from the gas extraction hole 32 and is discharged from the other end of the gas extraction pipe 33. Since the other end of the gas extraction pipe 33 is disposed near the intake port of the blower 16, the gas is sucked by the blower 16 and used as a combustion fuel of the burner 6.

The oil storage tank 19 is connected with the delivery pump 24 and the oil storage tank 19, and the outflow pipe 34 which comprises a part of the liquid fuel distribution line 23 is formed. This delivery pump 24 is a normal pressure pump, for example, a pump whose discharge pressure is about 100 kPa. The outflow pipe 34 is inserted through the ceiling wall 19a, and the outflow opening 34a located in the oil storage tank 19 of the outflow pipe 34 is opened downward. By operating the delivery pump 24, the liquid fuel in the low oil tank 19 is sent into the reformer 5 through the outlet pipe 34.

The control level S of the liquid fuel in the oil storage tank 19 is controlled by the float valve 35. When the float valve 35 attached to one end of the arm floats on the liquid level, and the liquid level is lower than the control level S, the float valve 35 shows the inlet 31a of the inlet pipe 31 as shown in FIG. The liquid fuel flows into the oil storage tank 19 from). When the liquid level reaches the water level S, as shown in Fig. 17, the tab 37 attached to the other end of the arm is fitted into the inlet 31a of the inlet tube 31, and the inside of the inlet tube 31 The flow path is closed.

The catalyst piece 38 of the desulfurization catalyst in the desulfurization unit 8 is mixed in the liquid fuel flowing into the storage tank 19. By storing liquid fuel in the oil storage tank 19, the catalyst piece 38 of this desulfurization catalyst sinks in the oil storage tank 19, and collects in the lower part of the oil storage tank 19. As shown in FIG. That is, the lower part of the oil storage tank 19 functions as the catalyst piece storage part 39 which collects the catalyst piece 38 of a desulfurization catalyst. Since the catalyst piece 38 of this desulfurization catalyst adversely affects the facilities of the rear end, the outlet port 34a is located above the catalyst piece storage section 39 so as not to flow out of the outlet pipe 34. Further, the inlet 31a is located above the catalyst piece storage 39 so that the liquid fuel introduced from the inlet pipe 31 does not detect the catalyst piece 38 of the desulfurization catalyst.

In order to discharge the catalyst piece 38 of the desulfurization catalyst accumulated in the catalyst piece storage part 39 from the storage tank 19, a discharge pipe 40 is connected to the bottom wall of the storage tank 19. The solenoid valve 41 is provided in the discharge pipe 40, and the catalyst piece 38 accumulated in the catalyst piece storage part 39 while the solenoid valve 41 is closed is opened by opening the solenoid valve 41 easily. Can be discharged.

In the fuel cell system 1 configured as described above, the raw fuel is first introduced into the desulfurization unit 8, and in the desulfurization unit 8, sulfur content is removed from the liquid fuel by the desulfurization catalyst in a state of high temperature and high pressure. The liquid fuel and the gas discharged from the desulfurizer 8 are separated by being stored in the gas-liquid separation vessel 9, and the liquid fuel is introduced into the liquid fuel discharge line 18. In the liquid fuel discharge line 18, the liquid fuel is measured by the flow meter 26 on the downstream side of the capillary tube 21 and flows into the oil storage tank 19. The high pressure liquid fuel flows into the oil storage tank 19 maintained at normal pressure, whereby gas is separated from the liquid fuel. Then, the liquid fuel is stored in the oil storage tank 19 and then introduced into the reformer 5 through the liquid fuel distribution line 23 by the delivery pump 24. In addition, the gas is discharged through the gas discharge line 27 in the oil storage tank 19, supplied to the burner 6 by the blower 16, and used as fuel.

On the other hand, the original fuel is introduced into the burner 6 through the fuel line 25, and air is mainly introduced through the air distribution line 17. As a result, the reforming catalyst is heated by the burner 6 burning in the reformer 5, and reformed gas is generated from the liquid fuel. The reformed gas generated in the reformer 5 is introduced into the fuel cell stack 4, and the reformed gas is used in the fuel cell stack 4 to generate power.

On the other hand, the gas stored in the gas-liquid separation vessel 9 is introduced into the burner 6 through the gas discharge line 13 and used together with the liquid fuel as the fuel of the burner 6. In the case where the flow of gas is closed, the solenoid valve 14 has a plurality of circuits when the amount of gas in the gas-liquid separation vessel 9 detected by the float switch 11 exceeds a predetermined amount. Divide to open the distribution of gas.

In the oil storage tank 19, when the liquid level of the liquid fuel reaches the control level S, the inlet 31a of the inlet pipe 31 is closed by the float valve 35, and the inflow into the oil storage tank 19 is stopped. . When the liquid level of the liquid fuel is lower than the control level S, the inlet port 31a of the inlet pipe 31 is opened by the float valve 35 to start the inflow into the oil storage tank 19.

In addition, when the catalyst piece 38 accumulates in the catalyst piece storage part 39 of the oil storage tank 19, the solenoid valve 41 formed in the discharge pipe 40 is opened, and the catalyst piece 38 is stored in the oil storage tank 19. Eject from. The opening of the solenoid valve 41 may be set at a predetermined time interval.

In the fuel cell system 1 according to the present embodiment described above, a storage tank 19 for storing liquid fuel is disposed between the desulfurizer 8 and the reformer 5, and the storage tank 19 is provided in the storage tank 19. The gas extraction hole 32 opened to the atmosphere is formed. For this reason, the raw fuel is desulfurized at a high pressure in the desulfurizer 8, the desulfurized liquid fuel flows into the oil storage tank 19, and the gas contained in the liquid fuel is extracted from the gas extraction hole 32 and stored. The oil is discharged from within the tank 19. Since the gas contained in the liquid fuel is extracted, it is possible to increase the reliability of the flow rate measurement and the flow rate control of the liquid fuel on the downstream side of the oil storage tank 19. For this reason, the flow volume of the liquid fuel which flows into the reformer 19 can be controlled reliably, and the fall of reforming performance can be prevented. In addition, since the liquid fuel in a high pressure state does not flow downstream from the oil storage tank 19, there is no need of the equipment corresponding to high pressure, and the durability of the equipment of the rear end of the oil storage tank 19 can be improved, and the cost is low. It can be realized.

In addition, the fuel cell system 1 according to the fifth embodiment includes a positive pressure pump 7 for pumping raw fuel at a constant pressure in the desulfurizer 8 and a downstream side of the desulfurizer 8 and a low oil tank. The capillary tube 21 arrange | positioned more upstream than (19) is provided. For this reason, the raw fuel flows into the desulfurizer 8 at a constant pressure, while the outflow amount from the desulfurizer 8 is throttled. For this reason, the pressure in a desulfurizer can be made higher than atmospheric pressure, and the flow rate of a raw fuel (liquid fuel) can be kept low, without using an expensive pump.

In the fuel cell system 1 according to the fifth embodiment, the gas discharged together with the liquid fuel from the desulfurization unit 8 is separated from the liquid fuel in the gas-liquid separation vessel 9 to separate the gas discharge line 13. It is discharged from the gas-liquid separation vessel 9 through. The gas discharge line 13 is provided with a capillary tube 15 which inhibits the flow of gas on the downstream side of the solenoid valve 14 which opens and closes the flow of gas. For this reason, even if the flow of gas is opened by the solenoid valve 14 in order to discharge gas from the gas-liquid separation container 9 through the gas discharge line 13, the capillary tube 15 desulfurizer 8 The fall of the pressure in) is suppressed. Therefore, the pressure in the desulfurizer 8 can be maintained at a high pressure, and the sulfur content can be reliably removed from the raw fuel. On the other hand, the liquid fuel is introduced into the oil storage tank 19 through the liquid fuel discharge line 18. Since the flowmeter 26 is formed in the liquid fuel discharge line 18, the flow rate of the liquid fuel separated from gas can be measured stably.

Further, in the fuel cell system 1 according to the fifth embodiment, the catalyst piece 38 for desulfurization, which flows out together with the liquid fuel from the desulfurization unit 8, is located at the lower portion of the storage tank 19. It can collect in the storage part 39, and can prevent it from flowing into the reformer 5 of a rear end. In addition, since the inlet 31a and the outlet 34a of the liquid fuel in the oil storage tank 19 are located above the catalyst piece storage 39, the catalyst piece storage 39 by the inflow and outflow of the liquid fuel. ) Can be suppressed from flying out of the storage tank 19 and flowing into the reformer 5.

In general, when pumping liquid accumulated in the container, its outlet is formed at the bottom of the container so as not to suck air. In the fuel cell system 1 according to the fifth embodiment, the outlet port 34a is formed above the catalyst piece storage section 39 so that the catalyst accumulated in the catalyst piece storage section 39 is blown up to the storage tank 19. It can be suppressed that it flows out from and flows in into the reformer 5.

In the fuel cell system 1 according to the fifth embodiment, a burner 6 for heating the reformer 5 is provided, and the burner 6 burns outflow gas flowing out of the gas extraction hole 32. Used as fuel for dragons. For this reason, the outflow gas which flowed out from the gas extraction hole 32 can be prevented from flowing out around the fuel cell system 1. In addition, since the outflow gas is used as the fuel of the burner 6, it can contribute to energy saving.

As mentioned above, although preferred embodiment of 5th aspect of this invention was described in detail, various modifications are possible for the 5th aspect of this invention.

As shown in FIG. 18, it is not necessary to form the gas D and the gas discharge line 13 in the fuel cell system 1. As the fuel cell system 1a, the desulfurizer 8 and the oil storage tank 19 are directly connected by the liquid fuel gas distribution line 12, and the capillary on the liquid fuel gas distribution line 12 is connected. The tube 21 may be formed.

In addition, although the float valve 35 was provided in order to control the water level in the oil storage tank 19 in 5th Embodiment, it is not limited to this. As shown in FIG. 19 and FIG. 20, instead of the float valve 35, the fuel cell system 1 detects that the liquid level of the liquid fuel in the oil storage tank 19 has reached the low water level S1. ), A high water level sensor 52 for detecting that the high water level S2 has been reached, and a control unit 53 for controlling in accordance with the output signals of the low water level sensor 51 and the high water level sensor 52. As this low water level sensor 51 and the high water level sensor 52, a float switch, an electrode type water level sensor, a pressure type water level sensor, etc. can be used, for example.

In this case, the solenoid valve 42 is formed in the inflow pipe 31, and the opening / closing of this solenoid valve 42 is controlled by the opening / closing control part 54 with which the control part 53 is equipped. In addition, the controller 53 measures the time from the low water level sensor 51 to the low water level S1 until the high water level sensor 52 detects the high water level S2, and the measurement by the timer 55. On the basis of time, a calculation unit 56 for calculating the flow rate of the liquid fuel and a pump control unit 57 for controlling the constant pressure pump 7 based on the calculation result by the calculation unit 56 are provided.

When the liquid level of the liquid fuel in the low oil tank 19 reaches the low water level S1 from the state higher than the low water level S1, the low water level sensor 51 detects that the liquid level of the liquid fuel has become the low water level S1, and the electric signal is a low water level sensor. It is output from the 51 to the control part 53. When the electric signal output from the low water level sensor 51 is inputted by the opening / closing control part 54, the opening / closing control part 54 opens the solenoid valve 41 from the closed state, and liquid fuel will flow in into the storage tank 19. It begins to be.

When the liquid level of the liquid fuel in the low oil tank 19 reaches the high water level S2 from the state lower than the high water level S2, the high water level sensor 52 detects that the liquid level of the liquid fuel has reached the high water level S2, and the electric signal has a high water level. It is output from the sensor 52 to the control part 53. When the electrical signal output from the high water level sensor 52 is inputted by the opening / closing control part 54, the opening / closing control part 54 closes the solenoid valve 41 from the open state, and inflows into the oil storage tank 19 of liquid fuel. It stops.

On the other hand, the electrical signal output from the low water level sensor 51 and the electrical signal output from the high water level sensor 52 are input by the timer 55, respectively. The timer 55 measures the time from the input of the electrical signal output from the low water level sensor 51 to the input of the electrical signal output from the high water level sensor 52, and calculates an electrical signal indicating the measurement time. Output to 56. When the calculating part 56 inputs the electric signal which shows a measurement time from the timer 55, it calculates the flow volume of a liquid fuel based on the measurement time. The calculator 56 outputs an electric signal indicating the calculated flow rate to the pump controller 57. When the pump control part 57 inputs the electric signal which shows a flow volume from the calculating part 56, it controls the drive of the positive pressure pump 7 based on this flow volume.

In this case, since the time from the water level sensor to detecting the low water level until the high water level is detected by the timer, and the calculation means calculates the flow rate of the liquid fuel based on the measurement time by the timer, a flow meter is provided separately. There is no need to do it. This can further reduce the cost.

In addition, since the inlet 31a and the outlet 34a of the liquid fuel in the oil storage tank 19 are located below the low water level S1, the liquid fuel is prevented from foaming when the liquid fuel flows in, and the liquid fuel flows out. When it does, the air flows out from the surface, preventing air from entering.

In addition, the calculation unit 56 flows the liquid fuel into the oil storage tank 19 based on the flow rate of the liquid fuel flowing out of the outlet pipe 34 of the oil storage tank 19, the discharge amount of the delivery pump 24, and the like. May be calculated. In addition, the pump control part 57 may perform drive control of the positive pressure pump 7 based on the measurement time by the timer 55.

As shown in FIG. 21, as a modification of the fuel cell system 1 according to the fifth embodiment, the overflow pipe 43 may be connected to the storage tank 19. One end of the overflow pipe 43 is inserted into the ceiling wall of the oil storage tank 19, and one of the openings 43a is disposed at a position M higher than the water level S in the oil storage tank 19, and is opened downward. have. The overflow pipe 43 is piped along the outer side of the side wall 19c of the oil storage tank 19, and the other opening 43b is located outside the oil storage tank 19, and is opened downward. For this reason, even if the liquid fuel is filled in the oil storage tank 19 for some reason, such as a failure of the float valve 35, the liquid fuel is discharged from the oil storage tank 19 by the overflow pipe 43. As shown in FIG.

An oil pan 44 is disposed below the oil reservoir 19, and the liquid fuel discharged from the other opening 43b of the overflow pipe 43 facing downward is introduced into the oil pan 44. When the liquid fuel flows into the oil pan 44, the liquid fuel leaks into the oil pan 44 by the leak sensor 45 disposed on the bottom surface of the oil pan 44. In this case, the control device (not shown) stops the supply of the liquid fuel by controlling such as stopping the operation of the constant pressure pump 7 in accordance with the input of the detection signal by the leak sensor 45, thereby preventing the liquid. The outflow of fuel can be stopped.

In addition, the overflow pipe is not limited to the above-described form, and may be formed in a straight line. In this case, an overflow pipe is inserted from the opening of the bottom wall 19b of the oil storage tank 19, and one end is arrange | positioned in the position set at the height of the full water level in the oil storage tank 19, and the other end is It is located below the bottom wall 19b other than the oil storage tank 19, and is arrange | positioned so that it may open toward the oil pan 44. As shown in FIG.

The fuel cell system according to the fifth embodiment can be modified in various ways. The fuel cell stack 4 is not limited to the solid polymer fuel cell stack but may be a solid oxide fuel cell stack or the like. As the raw fuel, in addition to kerosene, gasoline, naphtha, diesel, methanol, ethanol, DME (dimethyl ether), biofuel using biomass, or the like may be used. The reformer 5 is not limited to steam reforming, but may be partial oxidation reforming or self thermal reforming. In addition, a constant flow pump may be used instead of the constant pressure pump 7. However, it is preferable to use the constant pressure pump 7 from the viewpoint of management of the pressure in the desulfurization unit 8.

(6th Embodiment)

Hereinafter, the fuel cell system 1 according to the sixth embodiment will be described in detail with reference to FIGS. 22 and 23.

As shown in FIG. 22, the fuel cell system 1 includes a reforming apparatus 2 for generating reformed gas containing hydrogen and a desulfurization apparatus for removing sulfur content from liquid fuel for supplying the reforming apparatus 2 ( 3) and a fuel cell stack 4 for generating power using reformed gas generated by the reformer 2. For example, kerosene is used as a liquid fuel in view of the fuel cell system 1 being easily available and independently stored by being used as a household power supply. Moreover, the reforming system R is comprised by the part of the fuel cell system 1 except the fuel cell stack 4 (reformer 2, desulfurization apparatus 3, and pumps 16, 22, 24, etc. which are mentioned later). It is.

The reformer 2 has a reformer 5 for steam reforming liquid fuel to generate reformed gas, and a burner 6 for heating the reforming catalyst contained in the reformer 5. The burner 6 heats the reforming catalyst for promoting the steam reforming reaction, and supplies the reforming catalyst with the heat necessary to effectively exhibit the catalytic reaction. In the reformer 5, the liquid fuel introduced from the desulfurization apparatus 3 vaporizes into a source gas, and the reforming catalyst promotes the steam reforming reaction between the source gas and steam (water), and generates a reformed gas rich in hydrogen. do.

The fuel cell stack 4 is a solid polymer fuel cell stack configured by stacking a plurality of battery cells, and generates electricity using the reformed gas obtained by the reformer 2. Each battery cell has an anode, a cathode, and an ion exchange membrane of a polymer which is an electrolyte disposed between the anode and the cathode. In each battery cell, reformed gas is introduced into the anode, air is introduced into the cathode, and an electrochemical power generation reaction is performed.

The desulfurization apparatus 3 includes a desulfurizer 8 for removing sulfur content from the liquid fuel introduced by the constant pressure pump 7, and a liquid fuel and gas (methane gas or hydrogen gas, etc.) discharged from the desulfurizer 8. It has the gas-liquid separation container 9 which stores. In the gas-liquid separation container 9, a float switch 11 for detecting the liquid level of the liquid fuel is provided for detecting the amount of gas. The gas-liquid separation vessel 9 is disposed above the desulfurizer 8, and one end of the liquid fuel and gas distribution line 12 through which the liquid fuel and gas flow is connected to the bottom wall of the desulfurizer 8, The other end is connected to the bottom wall of the gas-liquid separation container 9. Thereby, the gas discharged | emitted from the desulfurizer 8 can be introduce | transduced certainly in the gas-liquid separation container 9. Although not shown, a filter is formed in the liquid fuel and gas distribution line 12 for the purpose of removing the desulfurization catalyst contained in the liquid fuel from which sulfur content has been removed by the desulfurization unit 8. In the present embodiment, for example, a filter having a scale interval of about 0.026 mm can be used.

One end of the gas discharge line 13 for discharging the gas stored above in the gas-liquid separation vessel 9 from the gas-liquid separation vessel 9 is connected to the ceiling wall of the gas-liquid separation vessel 9. The other end of the gas discharge line 13 is connected to a burner 6 that heats the reforming catalyst of the reformer 5. The gas discharge line 13 is provided with a solenoid valve 14 for opening and closing the flow of gas. The solenoid valve 14 cooperates with the gas-liquid separation container 9 to constitute a degas D that removes gas from the liquid fuel. Moreover, the capillary tube 15 which prevents gas flow is provided in the downstream of the solenoid valve 14 in the gas discharge line 13. Moreover, the air distribution line 17 in which the pump 16 for introducing air to the burner 6 is formed in the downstream of the capillary tube 15 in the gas discharge line 13 is connected.

On the other hand, one end of the liquid fuel discharge line 18 for discharging the liquid fuel stored below in the gas-liquid separation vessel 9 from the gas-liquid separation vessel 9 is connected to the bottom wall of the gas-liquid separation vessel 9. . The other end of the liquid fuel discharge line 18 is connected to the side wall of the storage container 19 disposed above the gas-liquid separation container 9. The liquid fuel discharge line 18 is formed with a capillary tube 21 that inhibits the flow of liquid fuel.

Here, the capillary tube 21 is a spirally wound microfine tube. Under the pressure determined by the constant pressure pump, the inner diameter of the capillary tube 21 and when it is wound so that the flow rate of the liquid fuel becomes a low flow rate (for example, 10 g / min or less in a 1 kW fuel cell system). The diameter is set. Specifically, the capillary tube 21 preferably has an inner diameter of about 0.1 mm to 0.7 mm, and preferably is wound up so as to have a diameter of about 10 mm to 100 mm. The total length of the capillary tube 21 is about 600 mm in the sixth embodiment, but the required flow rate, the pressure in the desulfurizer 8, the inner diameter of the capillary tube 21 and the capillary tube 21 It can set in consideration of the diameter at the time of winding. As mentioned above, although the filter is provided in the liquid fuel and gas distribution line 12, since the desulfurization catalyst of the particle diameter smaller than the scale | interval spacing passes through a filter, the inner diameter of the capillary tube 21 is 0.1 mm. If less, the capillary tube 21 tends to be clogged by the desulfurization catalyst. On the other hand, when the inner diameter of the capillary tube 21 exceeds 0.7 mm, the entire capillary tube 21 required for the liquid fuel delivery at a low flow rate while maintaining the inside of the desulfurizer 8 at a high pressure. There is a tendency for the length to become long, making compactization difficult. Moreover, the pressure loss can be adjusted according to the magnitude | size of the diameter when the capillary tube 21 is wound up.

The bottom wall of the storage container 19 has a liquid fuel distribution line 23 provided with a pump 22 for introducing a liquid fuel stored below in the storage container 19 to the reformer 5, and the liquid fuel. The liquid fuel distribution line 25 provided with the pump 24 for introducing into the burner 6 is connected. Thus, by storing liquid fuel once in the storage container 19, supply of the liquid fuel to the reformer 5 by the pump 22, and the liquid fuel to the burner 6 by the pump 24 Supply can be stabilized.

In the fuel cell system 1 configured as described above, the liquid fuel is first introduced into the desulfurization unit 8, and in the desulfurization unit 8, sulfur content is removed from the liquid fuel by the desulfurization catalyst in a state of high temperature and high pressure. The liquid fuel and gas discharged from the desulfurizer 8 are stored in the gas-liquid separation vessel 9, and the liquid fuel is reformer through the liquid fuel discharge line 18, the storage vessel 19, and the liquid fuel distribution line 23. It is introduced in (5). At this time, the liquid fuel is introduced into the burner 6 through the liquid fuel discharge line 18, the storage vessel 19, and the liquid fuel distribution line 25, and air is introduced through the air distribution line 17. . As a result, in the reformer 5, the reforming catalyst is heated by the burner 6 burning, and the liquid fuel is used to generate the reformed gas. The reformed gas generated in the reformer 5 is introduced into the fuel cell stack 4, and the reformed gas is used in the fuel cell stack 4 to generate power.

On the other hand, the gas stored in the gas-liquid separation vessel 9 is introduced into the burner 6 through the gas discharge line 13 and used together with the liquid fuel as the fuel of the burner 6. In this manner, the gas discharged from the desulfurizer 8 together with the liquid fuel can be effectively used as the fuel of the burner 6. In the case where the flow of gas is closed, the solenoid valve 14 is divided into a plurality of times when the amount of gas in the gas-liquid separation vessel 9 detected by the float switch 11 exceeds a predetermined amount. Open the distribution of gas.

In the sixth embodiment as described above, the capillary tube 21 is disposed downstream of the desulfurization unit 8. For this reason, by selecting the inner diameter and length of the capillary tube 21 suitably, the pressure and the flow volume of the liquid fuel in the desulfurizer 8 can be made into a desired size, without using an expensive pump. As a result, it is possible to realize the liquid feed at low flow rate easily and at low cost.

By the way, it is also conceivable to use an orifice, a needle valve, or the like instead of the capillary tube 21. However, since the flow path of the orifice portion is limited, the diameter of the orifice portion must be made extremely small in order to reduce the flow rate of the high-pressure liquid fuel discharged from the desulfurizer 8. Here, in the desulfurization unit 8, the desulfurization catalyst is desulfurized by the desulfurization catalyst, but the desulfurization catalyst may be contained in the liquid fuel from which the sulfur content is removed by the desulfurization unit 8. For this reason, when an orifice, a needle valve, etc. are used, the desulfurization catalyst which flowed out from the desulfurizer 8 may be blocked by the flow path of an orifice part.

However, in the fuel cell system 1 according to the sixth embodiment, since the capillary tube 21 is used as described above, the capillary tube (depending on the length of the capillary tube 21) 21) can increase the inner diameter to some extent. For this reason, clogging by a desulfurization catalyst is extremely unlikely to occur.

As mentioned above, although preferred embodiment of 6th aspect of this invention was described in detail, 6th aspect of this invention is not limited to said embodiment. For example, the fuel cell stack 4 is not limited to the solid polymer fuel cell stack but may be a solid oxide fuel cell stack or the like.

The reformer 5 is not limited to steam reforming, but may be partial oxidation reforming or self thermal reforming. The reforming method by the reformer 5 depends on the characteristics of liquid fuel, such as gasoline, naphtha, diesel, methanol, ethanol, DME (dimethyl ether), and biofuel using biomass.

In addition, a constant flow pump may be used instead of the constant pressure pump 7. However, it is preferable to use the constant pressure pump 7 from the viewpoint of management of the pressure in the desulfurization unit 8.

In addition, as shown in FIG. 23, it is not necessary to form the D, the gas discharge line 13 and the capillary tube 15 in the fuel cell system 1. That is, the desulfurizer 8 and the storage vessel 19 are directly connected by the liquid fuel and gas distribution line 12 to form the capillary tube 21 on the liquid fuel and gas distribution line 12. You may also do it. At this time, the pump 16 and the burner 6 are directly connected by the air distribution line 17.

1 is a configuration diagram of one embodiment of a fuel cell system according to the first embodiment.

2 is a block diagram of a desulfurization apparatus provided in the fuel cell system of FIG.

FIG. 3 is a graph showing the relationship between the temperature and pressure of the liquid fuel in the desulfurizer in the desulfurization apparatus of FIG.

4 is a flowchart showing a startup operation of the desulfurization apparatus of FIG.

5 is a configuration diagram of one embodiment of a fuel cell system according to the second embodiment.

6 is a configuration diagram of a desulfurization apparatus provided in the fuel cell system of FIG. 5.

FIG. 7 is a diagram showing an example of a relationship between an operating state and a set temperature in the desulfurization apparatus of FIG. 6. FIG.

FIG. 8 is a flowchart showing operation in the desulfurization apparatus of FIG. 6. FIG.

9 is a configuration diagram of one embodiment of a fuel cell system according to the third embodiment.

10 is a configuration diagram of a desulfurization apparatus provided in the fuel cell system of FIG. 9.

FIG. 11 is a table showing a relationship between temperature and pressure at the time of stop of operation in the desulfurization apparatus of FIG. 10; FIG.

12 is a flowchart showing a stop operation of the desulfurization apparatus of FIG. 10.

13 is a configuration diagram of an embodiment of a fuel cell system according to the fourth embodiment.

FIG. 14 is a graph showing the relationship between the pressure of the float switch, the solenoid valve and the desulfurizer in the fuel cell system of FIG.

15 is a diagram schematically showing a fuel cell system according to a fifth embodiment.

FIG. 16 is a view showing a oil storage tank of the fuel cell system according to the fifth embodiment. FIG.

FIG. 17 is a view showing a oil storage tank of the fuel cell system according to the fifth embodiment. FIG.

18 is a diagram schematically showing a modification of the fuel cell system according to the fifth embodiment.

FIG. 19 is a diagram showing a modification of the oil storage tank of the fuel cell system according to the fifth embodiment. FIG.

FIG. 20 is a diagram showing a control unit of the fuel cell system according to the fifth embodiment in the modification shown in FIG. 19. FIG.

21 is a diagram showing a modification of the oil storage tank included in the fuel cell system according to the fifth embodiment.

22 is a diagram schematically showing a fuel cell system according to a sixth embodiment.

Fig. 23 is a diagram schematically showing another example of a fuel cell system according to the sixth embodiment.

Claims (28)

A desulfurizer containing a desulfurization catalyst for removing sulfur content from liquid fuel for supplying to a reformer that generates reformed gas containing hydrogen, Heating means for heating the desulfurization catalyst; Liquid fuel introduction means for introducing the liquid fuel into the desulfurizer; Liquid fuel derivation means for deriving the liquid fuel from the desulfurizer; Temperature measuring means for measuring a temperature of the liquid fuel in the desulfurizer; Pressure measuring means for measuring the pressure of the liquid fuel in the desulfurizer; A control means for controlling said heating means, said liquid fuel introduction means and said liquid fuel derivation means, The control means is such that the temperature measured by the temperature measuring means becomes a predetermined temperature, and the pressure measured by the pressure measuring means is equal to or higher than the saturated vapor pressure of the liquid fuel at the predetermined temperature and the internal pressure of the desulfurizer. And the heating means, the liquid fuel introduction means and the liquid fuel derivation means are controlled so as to have a predetermined pressure below. The method of claim 1, When the control means raises the pressure measured by the pressure measuring means, the amount of introduction of the liquid fuel by the liquid fuel introduction means increases the amount of derivation of the liquid fuel by the liquid fuel derivation means. When reducing the pressure measured by the pressure measuring means, reducing the amount of the liquid fuel introduced by the liquid fuel introduction means and increasing the amount of the liquid fuel derived by the liquid fuel derivation means Desulfurization apparatus characterized by. Desulfurization apparatus according to claim 1, A reformer for producing a reformed gas containing hydrogen using a liquid fuel from which sulfur is removed by the desulfurization apparatus; And a fuel cell stack for generating power using the reformed gas generated by the reformer. A desulfurizer containing a desulfurization catalyst for removing sulfur content from liquid fuel for supplying to a reformer that generates reformed gas containing hydrogen, Heating means for heating the desulfurization catalyst; Liquid fuel introduction means for introducing the liquid fuel into the desulfurizer; Liquid fuel derivation means for deriving the liquid fuel from the desulfurizer; Temperature measuring means for measuring a temperature of the liquid fuel in the desulfurizer; A control means for controlling said heating means, said liquid fuel introduction means and said liquid fuel derivation means, The control means controls at least one of the liquid fuel introduction means and the liquid fuel derivation means to stop the supply of the liquid fuel from the desulfurizer when a pause signal is input, and at the same time, the temperature measuring means. The desulfurization apparatus, characterized in that the heating means is controlled so that the temperature measured by the temperature is higher than the normal temperature and lower than the temperature during normal operation. The method of claim 4, wherein A storage container for temporarily storing the liquid fuel derived by the liquid fuel derivation means; And a storage amount measuring means for measuring the storage amount of the liquid fuel stored in the storage container, And the storage amount measuring means outputs the pause signal to the control means when the storage amount reaches a predetermined storage amount. The desulfurization apparatus according to claim 4, A reformer for producing a reformed gas containing hydrogen using a liquid fuel from which sulfur is removed by the desulfurization apparatus; And a fuel cell stack for generating power using the reformed gas generated by the reformer. A desulfurizer containing a desulfurization catalyst for removing sulfur from liquid fuel for supplying to a reformer that generates reformed gas containing hydrogen; Liquid fuel introduction means for introducing the liquid fuel into the desulfurizer; Liquid fuel derivation means for deriving the liquid fuel from the desulfurizer; Temperature measuring means for measuring a temperature of the liquid fuel in the desulfurizer; Pressure measuring means for measuring the pressure of the liquid fuel in the desulfurizer; A control means for controlling the liquid fuel introduction means and the liquid fuel derivation means, When the temperature measured by the said temperature measuring means becomes below the predetermined temperature lower than the temperature in normal operation, the said control means makes the said liquid fuel so that the pressure measured by the said pressure measuring means will be predetermined pressure which is a static pressure. Desulfurization apparatus characterized in that it controls the introduction means and the liquid fuel derivation means. The method of claim 7, wherein When the control means raises the pressure measured by the pressure measuring means, the amount of introduction of the liquid fuel by the liquid fuel introduction means is increased and at the same time, the amount of derivation of the liquid fuel by the liquid fuel derivation means is reduced. When the pressure measured by the pressure measuring means is lowered, the amount of the liquid fuel introduced by the liquid fuel introduction means is decreased while the amount of the liquid fuel derived by the liquid fuel derivation means is increased. Desulfurization apparatus. Desulfurization apparatus according to claim 7, A reformer for producing a reformed gas containing hydrogen using a liquid fuel from which sulfur is removed by the desulfurization apparatus; And a fuel cell stack for generating power using the reformed gas generated by the reformer. A desulfurizer for removing sulfur content from the liquid fuel for supplying to a reformer that generates reformed gas containing hydrogen; A gas-liquid separation vessel for storing the liquid fuel and gas discharged from the desulfurizer; A liquid fuel discharge line for discharging the liquid fuel from the gas-liquid separation vessel; A gas discharge line for discharging the gas from the gas-liquid separation vessel; An opening / closing valve formed in the gas discharge line to open and close the flow of the gas; And a throttle formed in the gas discharge line on the downstream side of the on / off valve and inhibiting the flow of the gas. The method of claim 10, The desulfurization apparatus is characterized in that the on-off valve opens the flow of the gas in a plurality of times when the amount of the gas in the gas-liquid separation vessel exceeds a predetermined amount when the flow of the gas is closed. . The method of claim 10, The gas discharge line is connected to a burner for heating the reforming catalyst of the reformer. Desulfurization apparatus according to claim 10, A reformer for producing a reformed gas containing hydrogen using a liquid fuel from which sulfur is removed by the desulfurization apparatus; And a fuel cell stack for generating power using the reformed gas generated by the reformer. A desulfurizer which removes sulfur from the raw fuel of liquid at a pressure higher than atmospheric pressure to produce liquid fuel, A storage tank for forming a gas extraction hole open to the atmosphere, and storing the liquid fuel discharged from the desulfurizer; A delivery pump for sending the liquid fuel from the oil reservoir, A reformer disposed on a downstream side of the delivery pump and configured to reform the liquid fuel to generate a reformed gas; And a fuel cell stack for generating power using the reformed gas. The method of claim 14, A constant pressure pump for pumping the raw fuel at a constant pressure in the desulfurizer; And a capillary tube disposed downstream of the desulfurizer and upstream of the oil storage tank. The method of claim 15, A gas-liquid separation vessel for separating the liquid fuel and the gas discharged from the desulfurizer, A liquid fuel discharge line for discharging the liquid fuel from the gas-liquid separation vessel; A gas discharge line for discharging the gas from the gas-liquid separation vessel; An opening / closing valve formed in the gas discharge line to open and close the flow of the gas; A throttle formed on the downstream side of the open / close valve in the gas discharge line and inhibiting the flow of the gas; A flow meter formed in said liquid fuel discharge line, The capillary tube is formed upstream of the flow meter in the liquid fuel discharge line, And the reservoir tank is connected to the liquid fuel discharge line on a downstream side of the flow meter in the liquid fuel discharge line. The method of claim 14, A water level sensor for detecting the low water level and the high water level of the liquid fuel in the low oil tank; A timer for measuring a time from the water level sensor detecting the low water level to detecting the high water level; And a calculation means for calculating a flow rate of the liquid fuel based on the measurement time by the timer. The method of claim 14, The lower part of the oil storage tank functions as a catalyst piece storage part for collecting the desulfurization catalyst pieces introduced together with the liquid fuel from the desulfurizer, A fuel cell system, characterized in that the inlet and outlet of the liquid fuel in the reservoir tank is located above the reservoir section of the catalyst piece. The method of claim 14, An oil pan disposed below the oil storage tank, An overflow pipe disposed at one of the openings in the reservoir, and at the same time the other opening is disposed outside the reservoir, and at the same time a downward pipe is disposed toward the oil pan; And a leak sensor disposed in the oil pan. The method of claim 14, A burner for heating the reformer, And a gas discharge line for the burner to use the effluent gas flowing out from the gas extraction hole as fuel for combustion. Pump for delivering liquid fuel, A desulfurizer disposed on the downstream side of the pump, for removing sulfur from the liquid fuel; A capillary tube disposed downstream of the desulfurizer, through which liquid fuel from which sulfur is removed by the desulfurizer passes; A reformer disposed downstream of the capillary tube and generating reformed gas containing hydrogen using a liquid fuel from which sulfur content is removed by the desulfurizer; And a fuel cell stack for generating power using the reformed gas generated by the reformer. The method of claim 21, The fuel cell system, characterized in that the pump is a constant pressure pump. The method of claim 21, Fuel cell system, characterized in that the inner diameter of the capillary tube is 0.1mm to 0.7mm. The method of claim 21, And the capillary tube is spirally wound. Pump for delivering liquid fuel, A desulfurizer disposed on the downstream side of the pump, for removing sulfur from the liquid fuel; A capillary tube disposed downstream of the desulfurizer, through which liquid fuel from which sulfur is removed by the desulfurizer passes; And a reformer disposed downstream of the capillary tube and using a liquid fuel from which sulfur is removed by the desulfurizer to produce a reformed gas containing hydrogen. The method of claim 25, Wherein said pump is a constant pressure pump. The method of claim 25, The reforming system, characterized in that the inner diameter of the capillary tube is 0.1mm to 0.7mm. The method of claim 25, And the capillary tube is spirally wound.

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