JP2009079183A - Method for operating desulfurization apparatus and desulfurization apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation method of a desulfurization apparatus, which allows the prevention of the deterioration of a desulfurization catalyst, and the desulfurization apparatus. <P>SOLUTION: Provided is an operation method for operating the desulfurization apparatus 1 equipped with a desulfurizer 11 loaded with the desulfurization catalyst 11a and a desulfurized material tank 12 that stores a desulfurized material desulfurized in the desulfurizer 11. At start-up and/or shut-down of the desulfurization apparatus 1, the pressure inside the desulfurizer is increased by pumping the desulfurized material to the desulfurizer 11 so as to satisfy a condition in which the initial boiling point of a hydrocarbon material in the desulfurizer becomes higher than the temperature of the desulfurization catalyst. At start-up, the desulfurized material is fed to the desulfurizer 11 so as to circulate the desulfurized material between the desulfurized material tank 12 and the desulfurizer 11 until the temperature of the desulfurization catalyst 11a reaches a catalyst activation temperature at which it is activated. At shut-down, the desulfurizer 11 is purged with the desulfurized material until the desulfurization catalyst 11a reaches a temperature equal to or below the initial boiling point of the hydrocarbon material under ordinary pressure. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a desulfurization apparatus operation method and a desulfurization apparatus, and more particularly to a desulfurization apparatus operation method and a desulfurization apparatus capable of preventing deterioration of a desulfurization catalyst.

Conventionally, a desulfurization apparatus is used in a fuel cell system or the like as an apparatus for removing harmful sulfur from a hydrocarbon raw material such as kerosene (for example, Patent Document 1).
A conventional desulfurization apparatus will be described with reference to FIGS. In the drawings to be referred to, FIG. 5 is a configuration diagram for explaining the configuration of a conventional desulfurization apparatus, FIG. 6 is a graph for explaining the operation of the conventional desulfurization apparatus, and FIG. It is a flowchart for demonstrating operation | movement.

  As shown in FIG. 5, a conventional desulfurization apparatus 1 ′ includes a desulfurizer 11 ′ filled with a desulfurization catalyst 11a ′, a desulfurized kerosene tank 12 ′ for storing desulfurized kerosene desulfurized by the desulfurizer 11 ′, A heater 13 'for heating the desulfurization catalyst 11a' and a pump P 'for pumping kerosene (JIS No. 1 kerosene) stored in the raw material tank 1a' to the desulfurizer 11 'are configured.

The desulfurization apparatus 1 'performs a desulfurization process while circulating JIS No. 1 kerosene in the desulfurizer 11'. In order to activate the desulfurization catalyst 11a ', it is necessary to heat the heater 13' to a predetermined catalyst activation temperature. There is.
Therefore, when starting the conventional desulfurization apparatus 1 ′, as shown in FIG. 6A, the heater 13 ′ is turned on (S1) and the temperature Tc of the desulfurization catalyst 11a ′ is measured (S2). ), When the desulfurization catalyst temperature Tc reached the catalyst activation temperature (S3), the pump P ′ was turned on (S4), and the desulfurization treatment was performed while circulating JIS No. 1 kerosene through the desulfurizer 11 ′.

That is, as shown in FIG. 7, when the heater 13 'is turned on and the heater temperature _TH is raised to the heater target temperature, the desulfurization catalyst temperature Tc also rises and reaches a predetermined catalyst activation temperature (t ₂ ). Thereafter, the pump P ′ is driven (t ₂ ), and desulfurization is performed while circulating JIS No. 1 kerosene in the desulfurizer 11 ′.
When the desulfurization apparatus 1 ′ is stopped, the heater 13 and the pump P ′ are turned off as shown in FIG. 6 (b).

JP 2007-70502 A

However, when the pressure Pr in the desulfurizer is measured to determine the initial boiling point Bp of kerosene, as shown in FIG. 7, the temperature at which the heater 13 'is turned on and the desulfurization catalyst 11a' is activated (JIS No. 1). When heated to the kerosene supply permission temperature), the desulfurization catalyst temperature Tc exceeds the initial boiling point Bp of kerosene (t1 to t2), so the kerosene inside the desulfurizer 11 'evaporates and a gas phase is formed. As the temperature inside the desulfurizer rises, the pressure in the gas phase (desulfurizer pressure Pr) gradually increases and the liquid level of kerosene decreases.
For this reason, there has been a problem that the desulfurization catalyst 11a is deteriorated by depositing carbonized kerosene on the catalyst which has been dried by exposing the desulfurization catalyst 11a 'to the gas phase.

  On the other hand, if kerosene is supplied in a state where the desulfurization catalyst temperature Tc is low for the purpose of maintaining the liquid level of kerosene, the desulfurization catalyst 11a ′ is not activated because the desulfurization catalyst 11a ′ is not activated. There was a problem that the life of 11a 'was reduced. Further, there is a risk that kerosene that is insufficiently desulfurized may be stored in the desulfurized kerosene tank 12 ', and kerosene that is insufficiently desulfurized and desulfurized kerosene are mixed.

  Therefore, an object of the present invention is to provide a method for operating a desulfurization apparatus and a desulfurization apparatus that can prevent the desulfurization catalyst from deteriorating in order to solve the above-described problems.

  In order to solve the above problems, an invention according to claim 1 is directed to a desulfurizer filled with a desulfurization catalyst for removing sulfur contained in a hydrocarbon raw material, and a desulfurization raw material tank for storing a desulfurized raw material desulfurized by the desulfurizer. The initial depot point of the hydrocarbon raw material in the desulfurizer becomes higher than the temperature of the desulfurization catalyst when the desulfurization apparatus is started and / or stopped. In order to satisfy the conditions, a pressure increasing step is included in which the desulfurization raw material is pumped to the desulfurizer to increase the pressure in the desulfurizer.

According to such a process, when the desulfurizer is started and / or stopped where the desulfurization catalyst temperature rises and falls, the condition that the initial accumulation point of the hydrocarbon raw material in the desulfurizer is higher than the temperature of the desulfurization catalyst is set. The temperature of the hydrocarbon raw material supplied to the desulfurizer is set lower than its initial accumulation point so as to satisfy.
For this reason, the deterioration of the desulfurization catalyst can be prevented by preventing evaporation of the hydrocarbon raw material and preventing the desulfurization catalyst from being exposed to the gas phase.
Moreover, the hydrocarbon raw material and the desulfurized raw material can be prevented from being mixed by pumping the desulfurized raw material after desulfurization, not the hydrocarbon raw material before desulfurization, to the desulfurizer.

The invention according to claim 2 is the operation method of the desulfurization apparatus according to claim 1, wherein the pressurization step at the start-up is performed in the desulfurizer until the catalyst activation temperature at which the desulfurization catalyst is activated is reached. It includes a circulation step of supplying the desulfurized raw material and circulating the desulfurized raw material between the desulfurized raw material tank and the desulfurizer.
Here, the catalyst activation temperature refers to a temperature at which the processing capacity of the catalyst is secured and the hydrocarbon raw material may be supplied to the desulfurizer.

  According to such a process, the desulfurization raw material is supplied to the desulfurizer until the catalyst activation temperature at which the desulfurization catalyst is activated. It is possible to prevent the hydrocarbon raw material not being supplied to the desulfurization raw material tank.

  The invention according to claim 3 is the operation method of the desulfurization apparatus according to claim 2, wherein after the circulation step, the supply of the desulfurization raw material is stopped and the hydrocarbon raw material is supplied to the desulfurizer. Including a desulfurization step of performing desulfurization.

  According to this process, after reaching the catalyst activation temperature at which the desulfurization catalyst is activated, the hydrocarbon raw material is supplied to the desulfurizer to perform desulfurization, thereby efficiently preventing deterioration of the desulfurization catalyst. The desulfurization apparatus can be operated.

  The invention according to claim 4 is the operation method of the desulfurization apparatus according to claim 1, wherein the pressurization step at the time of stoppage is performed such that the temperature of the desulfurization catalyst is equal to or lower than the initial accumulation point of the hydrocarbon raw material at normal pressure. A purge step of purging the desulfurizer with the desulfurization raw material until it is lowered is included.

  According to such a process, when the desulfurization apparatus is stopped at which the temperature of the desulfurization catalyst is lowered, the desulfurizer until the temperature of the desulfurization catalyst is lowered below the initial distillation point of the hydrocarbon raw material at normal pressure (1 atm). Is purged with the above-mentioned desulfurization raw material, and since the desulfurization raw material is filled in the desulfurizer, evaporation of the hydrocarbon raw material can be prevented so that the desulfurization catalyst is not exposed to the gas phase. For this reason, it is possible to prevent the desulfurization catalyst from being deteriorated at the next start-up. Further, the hydrocarbon raw material and the desulfurization raw material can be prevented from being mixed.

  According to a fifth aspect of the present invention, there is provided a desulfurizer filled with a desulfurization catalyst for removing sulfur contained in a hydrocarbon raw material, a desulfurization raw material tank for storing a desulfurization raw material desulfurized by the desulfurizer, and heating the desulfurization catalyst. A desulfurization apparatus having a heating means for performing the above-mentioned and a pump for pumping the hydrocarbon raw material stored in the raw material tank to the desulfurizer, the desulfurization catalyst being filled with a desulfurization catalyst for removing sulfur contained in the hydrocarbon raw material A desulfurization raw material tank for storing the desulfurization raw material desulfurized by the desulfurizer, a heating means for heating the desulfurization catalyst, a pump for pumping the hydrocarbon raw material stored in the raw material tank to the desulfurizer, A desulfurization apparatus having a back pressure valve provided in a flow path from an outlet of the desulfurizer to an inlet of the desulfurization raw material tank, and opened at a preset back pressure; and a temperature of the desulfurization catalyst. detection A catalyst thermometer, a shut-off valve disposed between the raw material tank and the pump and shutting off the supply of the hydrocarbon raw material, and a flow path from the desulfurization raw material tank to the shut-off valve and the pump. A return flow path connected to the return flow path; and a return valve provided in the return flow path, wherein the back pressure is generated when the desulfurizer is started and / or stopped when the hydrocarbon raw material in the desulfurizer is used. Is set at a back pressure that increases the pressure in the desulfurizer by pumping the desulfurization raw material to the desulfurizer by the pump so that the initial point of the gas is higher than the temperature of the desulfurization catalyst. It is characterized by.

According to such a configuration, when starting and / or stopping the desulfurization apparatus in which the desulfurization catalyst temperature rises and falls, the condition that the initial accumulation point of the hydrocarbon raw material in the desulfurizer is higher than the temperature of the desulfurization catalyst. The back pressure of the back pressure valve is set so as to satisfy the condition, and the temperature of the hydrocarbon raw material supplied to the desulfurizer can be made lower than its initial accumulation point.
For this reason, the deterioration of the desulfurization catalyst can be prevented by preventing evaporation of the hydrocarbon raw material and preventing the desulfurization catalyst from being exposed to the gas phase.
Moreover, the hydrocarbon raw material and the desulfurized raw material can be prevented from being mixed by pumping the desulfurized raw material after desulfurization, not the hydrocarbon raw material before desulfurization, to the desulfurizer.

The invention according to claim 6 is the desulfurization apparatus according to claim 5, wherein the desulfurization apparatus is configured to start up until reaching a catalyst activation temperature at which the desulfurization catalyst is activated by the heating means. The shut-off valve is closed, the bypass valve is opened, the desulfurization raw material is supplied to the desulfurizer by the pump, and the desulfurization raw material is circulated between the desulfurization raw material tank and the desulfurizer. It is characterized by.
According to such a configuration, it is possible to prevent a hydrocarbon raw material that has not been desulfurized from being supplied to the desulfurized raw material tank even when the catalyst does not work efficiently.

  The invention according to claim 7 is the desulfurization apparatus according to claim 6, wherein after the catalyst activation temperature at which the desulfurization catalyst is activated is reached, the return valve is closed to stop the supply of the desulfurization raw material. At the same time, the shutoff valve is opened to supply the hydrocarbon raw material to the desulfurizer to perform desulfurization.

  The invention according to claim 8 is the desulfurization apparatus according to claim 5, wherein the desulfurization apparatus is configured such that the temperature of the desulfurization catalyst is reduced to a normal pressure while the temperature of the desulfurization catalyst is decreasing. The desulfurizer is purged with the desulfurized raw material by closing the shutoff valve and opening the return valve until the hydrogen raw material drops below the initial accumulation point of the hydrogen raw material.

  According to this configuration, by purging the desulfurizer with the desulfurization raw material, the desulfurization raw material is filled in the desulfurization device, so that the desulfurization catalyst can be prevented from being deteriorated at the next start-up. Further, the hydrocarbon raw material and the desulfurization raw material can be prevented from being mixed.

  The operation method of the desulfurization apparatus and the desulfurization apparatus according to the present invention can prevent the desulfurization catalyst from deteriorating.

A desulfurization apparatus in a fuel cell system according to an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is a block diagram showing a main configuration of a kerosene reforming fuel cell system 100 according to an embodiment of the present invention.
In addition, the desulfurization apparatus 1 which concerns on this invention is not limited to a fuel cell system, The application to uses, such as jet fuel and a diesel fuel, is also possible.

  As shown in FIG. 1, a kerosene reforming fuel cell system 100 according to an embodiment of the present invention includes a desulfurization apparatus 1 that removes sulfur contained in a hydrocarbon raw material, hydrocarbons and water vapor contained in kerosene. A reformer 2 that generates hydrogen by reaction, a fuel cell stack 3 that generates power by an electrochemical reaction between hydrogen and oxygen, and a cooling water tank 4 that stores reformed water and cooling water are provided. .

  As the hydrocarbon raw material, for example, kerosene (JIS No. 1 kerosene) having a very high energy density as a hydrogen source and having excellent portability and storability can be used. However, it is not limited to kerosene, gas oil such as light oil, heavy oil, asphaltene, oil sand oil, methanol, naphtha, coal liquefied oil, coal heavy oil, gasoline, etc., gas such as city gas, LPG, etc. Various hydrocarbon mixtures such as gaseous hydrocarbon mixtures can be used.

  As shown in FIG. 1, the reformer 2 is a reformer that generates a gas (reformed gas) containing hydrogen gas and carbon monoxide gas by reacting a hydrocarbon component contained in a hydrocarbon raw material with water vapor. 21, a CO converter 22 that modifies carbon monoxide contained in the reformed gas into carbon dioxide, and a CO remover 23 that generates a gas (hydrogen-containing gas) in which the remaining carbon monoxide is further reduced. ing.

The reformer 21 includes a reforming reaction catalyst (not shown) in which a noble metal-based catalyst such as platinum (Pt) that promotes the reaction between hydrocarbons and steam, and the amount of heat set to a predetermined reforming temperature. And a burner 21a to be supplied.
The reformer 21 is supplied with desulfurized desulfurized kerosene and reformed water from the cooling water tank 4. The burner 21a is supplied with combustion kerosene and anode off-gas containing unreacted hydrogen that has not been used in the fuel cell stack 3 as fuel.

  The CO converter 22 includes a shift reaction catalyst layer filled with a shift reaction catalyst such as iron oxide, copper-zinc system, or copper-chromium system. Then, the reformed gas generated by the reformer 21 is introduced into the CO converter 22.

  The CO remover 23 is supplied from the CO converter 22 by introducing PROX air in the presence of a CO selective oxidation catalyst (PROX reaction catalyst) in order to avoid the problem of electrode poisoning in the fuel cell stack 3. This is an apparatus for supplying the fuel cell stack 3 with a reformed gas (hydrogen-containing gas) obtained by oxidizing a small amount of carbon monoxide present in the shift gas and further reducing the carbon monoxide concentration of the shift gas.

  The fuel cell stack 3 introduces a hydrogen-containing gas supplied from the CO remover 23 into the anode, introduces air humidified by a humidifier (not shown) into the cathode, and performs an electrochemical reaction between hydrogen and oxygen. It generates electricity by.

Next, the configuration of the desulfurization apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 2 is a configuration diagram showing the configuration of the desulfurization apparatus according to the embodiment of the present invention.
As shown in FIG. 2, a desulfurization apparatus 1 according to an embodiment of the present invention includes a raw material tank 1a for storing kerosene (JIS No. 1 kerosene), which is a hydrocarbon raw material, and a desulfurization catalyst 11a for removing sulfur contained in kerosene. A desulfurizer 11 filled, a desulfurized kerosene tank 12 for storing desulfurized kerosene as a desulfurized raw material desulfurized by the desulfurizer 11, a heater 13 as a heating means for heating the desulfurized catalyst 11a, and a raw material tank 1a are stored. Detects the temperature of the desulfurization catalyst 11a, the pump P for pumping the JIS No. 1 kerosene to the desulfurizer 11, the back pressure valve provided in the flow path L from the outlet of the desulfurizer 11 to the inlet of the desulfurized kerosene tank 12 A desulfurization catalyst thermometer 11b, a pressure gauge 11c for detecting the pressure inside the desulfurizer, and a solenoid valve 15 that is disposed between the raw material tank 1a and the pump P and is a shut-off valve that shuts off the supply of JIS No. 1 kerosene The return flow path 16 communicated from the desulfurization kerosene tank 12 to the flow path between the electromagnetic valve 15 and the pump P, the check valve 18 as a return valve provided in the return flow path 16, and the desulfurizer 11. A heat exchanger HEX that heats JIS No. 1 kerosene to be sent to the vehicle and a control device 8 that controls the operation of the desulfurization device 1 are provided.

The desulfurizer 11 comprises a pressure-resistant housing made of a material resistant to liquid hydrocarbons, for example, a metal such as stainless steel, and the shape, size, material, and the like are not particularly limited, and desulfurization is performed. Therefore, it is appropriately selected according to the properties of the hydrocarbon raw material to be introduced, the sulfur content, the desulfurization addition, the processing amount, and the like.
The desulfurization catalyst 11a filled in the desulfurizer 11 is constituted by, for example, a cobalt-molybdenum-based, nickel-aluminum-based, or nickel-tungsten-based hydrodesulfurization catalyst, or a desulfurization catalyst in which these are combined with zinc oxide.

The heater 13 is provided outside the desulfurizer 11, heats the desulfurization catalyst 11 a filled in the desulfurizer 11 through the outer wall of the desulfurizer 11, and heats the desulfurization catalyst 11 a to a predetermined catalyst activation temperature. .
The heater 13 is not particularly limited as long as it can heat the desulfurization catalyst 11a, and is provided on the outside of the electric heater or the reactor provided so as to enclose the outer shell of the desulfurizer 11. Further, it can be constituted by a jacket pipe having a heating medium flow passage for circulating a heating medium supplied from a heating means such as a burner provided for heating the reformer constituting the fuel processor.

  The liquid level of the raw material tank 1a is set so that the water head pressure of the raw material tank 1a is higher than the crack pressure of the check valve 18 because the check valve 18 is adopted as a return valve. For this reason, when the electromagnetic valve 15 is closed, desulfurized kerosene is supplied from the desulfurized kerosene tank 12 to the pump P. When the electromagnetic valve 15 is opened, JIS No. 1 kerosene is supplied to the desulfurizer 11 via the pump P. Supplied.

  The back pressure valve 12a is provided to adjust the pressure inside the desulfurizer when the pump P is operating. The set pressure (back pressure) of the back pressure valve 12a is such that the desulfurized kerosene is supplied to the desulfurizer 11 by the pump P so that the initial point of kerosene in the desulfurizer 11 is higher than the temperature of the desulfurization catalyst 11a. The back pressure is set to increase the pressure in the desulfurizer by pumping.

  In the present embodiment, the pressure gauge 11c is disposed inside the desulfurizer 11. However, the pressure gauge 11c is not limited to this, and any pressure can be measured from the pump P to the back pressure valve 12a as long as the pressure inside the desulfurizer can be measured. It can also be provided in the flow path.

  The heat exchanger HEX is provided on the inflow side of the desulfurizer 11 and performs heat exchange between the JIS No. 1 kerosene that flows into the desulfurizer 11 and the desulfurized kerosene that flows out of the desulfurizer. That is, JIS No. 1 kerosene heated through the heat exchanger HEX is sent from the pump P to the desulfurizer 11. The desulfurized kerosene desulfurized by the desulfurizer 11 is cooled via the heat exchanger HEX and supplied to the desulfurized kerosene tank 12 via the back pressure valve 12a.

  The control device 8 includes a central processing unit and a storage device (not shown), and receives a start / stop signal associated with the power generation amount of the fuel cell stack 3 (FIG. 1) and the state of the reforming device 2 (FIG. 1), The operations of the heater 13, the pump P, and the electromagnetic valve 15 are controlled.

The operation of the desulfurization apparatus 1 configured as described above will be described mainly with reference to FIGS. FIG. 3 is a flowchart showing the operation of the desulfurization apparatus, where (a) is when starting and (b) is when stopping. FIG. 4 is a graph showing the state of operation of the desulfurization apparatus, where (a) is when starting and (b) is when stopping.
In FIG. 4, for convenience of explanation, there are cases in which the degree of gradient and the position of the break point are exaggerated.

  The desulfurization apparatus 1 according to an embodiment of the present invention is the first of kerosene (desulfurized kerosene supplied to the desulfurizer, or JIS No. 1 kerosene), which is a hydrocarbon raw material in the desulfurizer, by the controller 8 at the time of start and stop. In order to satisfy the condition that the sump point Bp becomes higher than the desulfurization catalyst temperature Tc, the pump P is configured to include a pressure increasing step of pumping desulfurized kerosene to the desulfurizer 11 to increase the pressure in the desulfurizer 11.

  In the present embodiment, the boosting step is performed both at the time of starting and at the time of stopping, but is not limited to this, and can be performed either at the time of starting or at the time of stopping. .

  In the pressurizing process at the time of starting, when the pump P is driven and the solenoid valve 15 is closed until the catalyst activation temperature at which the desulfurization catalyst 11a is activated by the heater 13 is reached, the check valve 18 is opened. A circulation step is provided so that desulfurized kerosene is supplied from the return flow path 16 and circulated between the desulfurized kerosene tank 12 and the desulfurizer 11.

Specifically, as shown in FIG. 3A, when starting the start process, the heater 13 is first turned on, and then the solenoid valve 15 is closed and the pump P is turned on (S1). When the solenoid valve 15 is closed, the check valve 18 opens, so that desulfurized kerosene is pumped to the desulfurizer 11 from the desulfurized kerosene tank 12 through the return flow path 16. When desulfurized kerosene is supplied to the desulfurizer 11, the pressure inside the desulfurizer 11 is rapidly increased (see Pr (t _{1 to} t ₂ ) in FIG. 4).

When the pressure inside the desulfurizer 11 increases to the set pressure of the back pressure valve 12a (Pr (t ₂ ) in FIG. 4), the desulfurized kerosene that has flowed out of the desulfurizer 11 flows from the flow path L (FIG. 2) to the heat exchanger. The desulfurized kerosene tank 12 is recovered through the HEX and the back pressure valve 12a.
In this manner, the desulfurized kerosene is circulated between the desulfurized kerosene tank 12 and the desulfurizer 11 (see Pr (t _{2 to} t ₃ ) in FIG. 4).

  At this time, as shown in FIG. 3 (a), the desulfurization catalyst temperature meter 11b measures the desulfurization catalyst temperature Tc (S2), and the desulfurization catalyst temperature is the catalyst activation temperature (the catalyst processing capacity is secured and JIS No. 1 kerosene is used. When the temperature that can be supplied (JIS No. 1 kerosene supply permission temperature) is reached, the electromagnetic valve 15 is opened to supply JIS No. 1 kerosene to the desulfurizer 11. Since the check valve 18 is closed when the solenoid valve 15 is opened, the supply of desulfurized kerosene from the desulfurized kerosene tank 12 is stopped, JIS No. 1 kerosene is supplied to the desulfurizer 11, and the desulfurized kerosene desulfurized by the desulfurizer 11 flows through the flow path. It is recovered through L to the desulfurized kerosene tank 12.

In this case, desulfurization catalyst temperature Tc, as shown in FIG. 4 (a), after rising rapidly with increasing the heater temperature _{T H (t 1 ~t 2)} , desulfurization catalyst depicts gradually gentle curve The catalyst activation temperature at which 11a is activated is reached (t ₃ ). Thereafter, it changes as asymptotic to a target temperature of the heater _(t 3 _~t 4).
In this way, when the desulfurization catalyst temperature Tc reaches the catalyst activation temperature, JIS No. 1 kerosene is supplied to start desulfurization, and the desulfurization process is performed.

The pressure Pr of the internal desulfurizer, as shown in FIG. 4 (a), was rapidly increased by the supply pressure of the rise and desulfurized kerosene heater temperature T _H, and reaches the setting pressure of the back pressure valve 12a to the set pressure Retained.
The initial accumulation point Bp of kerosene in the desulfurizer increases as the pressure Pr inside the desulfurizer increases by increasing the pressure Pr inside the desulfurizer.

  Here, the desulfurization apparatus 1 sets the back pressure of the back pressure valve 12a so as to satisfy the condition that the initial boiling point Bp of kerosene is higher than the desulfurization catalyst temperature Tc. For example, a test operation or the like is performed in advance, and the specifications and drive timings of the pump P and the heater 13 are appropriately set according to the specifications of the desulfurization apparatus 1. Usually, the desulfurizer 11 filled with the liquid phase by driving the pump P is used. Since the pressure inside is immediately increased (the pressure increase rate is faster than the temperature increase rate of the desulfurizer), the ON timing of the heater 13 may be before the pump P is driven as in this embodiment, or the heater 13 ON At the same time, the pump P may be driven, or the pump P may be driven before the heater 13 ON.

  Therefore, it is not necessary to particularly monitor the pressure Pr inside the desulfurizer, and it is possible to achieve the object of the present invention simply by driving the pump P and the heater 13 in the determined sequence. However, in view of the object of the present invention, for example, it is possible to control the heater 13 to be turned on after confirming that the pressure inside the desulfurizer 11 is increased with the pressure gauge 11c.

  In the pressurization process when the desulfurization apparatus 1 is stopped, the check valve 18 is closed by closing the solenoid valve 15 until the temperature of the desulfurization catalyst 11a falls below the initial accumulation point of kerosene, which is a hydrocarbon raw material at normal pressure (1 atm). And a purging step for purging the desulfurizer 11 with desulfurized kerosene.

Specifically, as shown in FIG. 3B, when the stop process is started, the heater 13 is turned off while the pump P is kept on, and then the electromagnetic valve 15 is closed (S1). When the solenoid valve 15 is closed, the check valve 18 is opened. Therefore, desulfurized kerosene is supplied from the desulfurized kerosene tank 12 through the return flow path 16 to the desulfurizer 11 instead of JIS No. 1 kerosene.
The desulfurization catalyst thermometer 11b measures the desulfurization catalyst temperature Tc (S2), and when the temperature of the desulfurization catalyst 11a falls below the initial boiling point of kerosene at normal pressure (S3), the pump P is turned off ( S4) The stop process is terminated.

In the purge step when the desulfurization apparatus 1 is stopped, in the desulfurizer 11, as shown in FIG. 4B, when the heater 13 is turned off (t ₄ ), the desulfurization catalyst temperature Tc gradually decreases (t ₄ ~t _5). On the other hand, since the pump P remains ON (t ₄ ), the pressure Pr inside the desulfurizer does not decrease (t _{4 to} t ₅ ). Thus, after the temperature of the desulfurization catalyst 11a falls below the kerosene initial accumulation point at 1 atm, the pump P is turned off (t ₅ ), and the desulfurization device 1 stop process is terminated.

As described above, according to the desulfurization apparatus 1 according to this embodiment, when the desulfurization apparatus in which the desulfurization catalyst temperature Tc rises and falls, the initial point Bp of kerosene in the desulfurizer 11 is the desulfurization catalyst temperature. The temperature of kerosene supplied to the desulfurizer 11 is set to be lower than its initial accumulation point Bp so as to satisfy the condition of becoming higher than Tc.
For this reason, deterioration of the desulfurization catalyst 11a can be prevented by preventing evaporation of kerosene and preventing the desulfurization catalyst 11a from being exposed to the gas phase. In addition, by sending desulfurized kerosene after desulfurization to the desulfurizer instead of JIS 1 kerosene before desulfurization, it is possible to prevent JIS 1 kerosene and desulfurized kerosene before desulfurization from being mixed.

As mentioned above, although embodiment of this invention was described, this invention is not limited to above-described embodiment, It can implement by changing suitably.
For example, although the check valve 18 is employed as the return valve in the present embodiment, the present invention is not limited to this, and an electromagnetic valve that electrically controls opening and closing by the control device 8 can also be employed.

1 is a configuration diagram showing a main configuration of a kerosene reforming fuel cell system 100 according to an embodiment of the present invention. It is a block diagram which shows the structure of the desulfurization apparatus which concerns on embodiment of this invention. It is a flowchart which shows operation | movement of the desulfurization apparatus which concerns on embodiment of this invention, (a) is at the time of starting, (b) is at the time of a stop. It is a graph which shows the state of operation | movement of the desulfurization apparatus which concerns on embodiment of this invention, (a) is at the time of starting, (b) is at the time of a stop. It is a block diagram for demonstrating the structure of the conventional desulfurization apparatus. It is a graph for demonstrating operation | movement of the conventional desulfurization apparatus. It is a flowchart for demonstrating operation | movement of the conventional desulfurization apparatus.

Explanation of symbols

1 Desulfurization equipment 1a Raw material tank (JIS No. 1 kerosene tank)
2 reformer 3 fuel cell stack 8 controller 11 desulfurizer 11a desulfurization catalyst 11b desulfurization catalyst thermometer 11c pressure gauge 12 desulfurization kerosene tank (desulfurization raw material tank)
12a Back pressure valve 13 Heater 15 Solenoid valve (shutoff valve)
16 Return flow path 18 Check valve (Return valve)
100 Kerosene reforming fuel cell system Bp Initial point HEX Heat exchanger L Flow path P Pump Pr Pressure inside desulfurizer Tc Desulfurization catalyst temperature (temperature of desulfurization catalyst)
_TH heater temperature

Claims (8)

A desulfurizer filled with a desulfurization catalyst for removing sulfur contained in a hydrocarbon raw material, and a desulfurization raw material tank for storing a desulfurized raw material desulfurized by the desulfurizer, comprising:
When the desulfurization apparatus is started and / or stopped, the desulfurization raw material is placed in the desulfurizer so that the initial point of the hydrocarbon raw material in the desulfurizer is higher than the temperature of the desulfurization catalyst. Including a pressurizing step for increasing the pressure in the desulfurizer by pumping,
A method for operating a desulfurization apparatus. The pressurizing step at the time of start-up includes supplying the desulfurization raw material to the desulfurizer until the catalyst activation temperature at which the desulfurization catalyst is activated and supplying the desulfurization raw material between the desulfurization raw material tank and the desulfurizer. Including a circulation step to circulate,
The operating method of the desulfurization apparatus according to claim 1. After the circulation step, including a desulfurization step of stopping the supply of the desulfurization raw material and supplying the hydrocarbon raw material to the desulfurizer to perform desulfurization;
The operating method of the desulfurization apparatus according to claim 2. The step of boosting at the time of stop is
Purging the desulfurizer with the desulfurization raw material until the temperature of the desulfurization catalyst falls below the initial distillation point of the hydrocarbon raw material at normal pressure,
The operating method of the desulfurization apparatus according to claim 1. A desulfurizer filled with a desulfurization catalyst for removing sulfur contained in the hydrocarbon raw material, a desulfurization raw material tank for storing the desulfurization raw material desulfurized by the desulfurizer, a heating means for heating the desulfurization catalyst, and a raw material tank A pump for pumping the stored hydrocarbon raw material to the desulfurizer,
A back pressure valve provided in a flow path from the outlet of the desulfurizer to the inlet of the desulfurization raw material tank, and opened at a preset back pressure;
A catalyst thermometer for detecting the temperature of the desulfurization catalyst;
A shutoff valve that is disposed between the feed tank and the pump and shuts off the supply of the hydrocarbon feedstock;
A return flow path communicating from the desulfurization raw material tank to a flow path between the shutoff valve and the pump;
A return valve provided in the return flow path,
The back pressure is adjusted by the pump so that the initial point of the hydrocarbon feedstock in the desulfurizer is higher than the temperature of the desulfurization catalyst when the desulfurizer is started and / or stopped. It is set with a back pressure that pumps the desulfurization raw material to the desulfurizer to increase the pressure in the desulfurizer,
Desulfurization equipment characterized by. The desulfurization apparatus closes the shut-off valve and the bypass valve until the catalyst activation temperature at which the desulfurization catalyst is activated by the heating means is reached at the time of start-up, and the desulfurizer is connected to the desulfurizer by the pump. Being configured to circulate the desulfurized raw material between the desulfurized raw material tank and the desulfurizer by supplying the raw material,
The desulfurization apparatus according to claim 5. After reaching the catalyst activation temperature at which the desulfurization catalyst is activated, the return valve is closed to stop the supply of the desulfurization raw material, and the shutoff valve is opened to supply the hydrocarbon raw material to the desulfurizer. Configured to perform desulfurization,
The desulfurization apparatus according to claim 6. The desulfurization apparatus closes the shut-off valve and returns the return valve while the temperature of the desulfurization catalyst is decreasing at the time of stoppage until the temperature of the desulfurization catalyst decreases below the initial distillation point of the hydrocarbon raw material at normal pressure. Configured to open a valve and purge the desulfurizer with the desulfurization raw material;
The operating method of the desulfurization apparatus of Claim 5 characterized by these.

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