JP7129323B2 - Hydrogen production device, hydrogen production method, compressor life monitoring control program - Google Patents

Description

In particular, the present invention relates to a hydrogen production apparatus for reforming a hydrocarbon feedstock to produce hydrogen, a hydrogen production method, and a compressor for monitoring the life of a compressor for pressurizing reformed gas sent to a hydrogen purifier. It relates to a life monitoring control program.

As a hydrogen production device for obtaining hydrogen, there is a configuration in which a raw hydrocarbon is reformed into a reformed gas by a steam reformer and then supplied to a PSA (Pressure Swing Adsorption) device. In this hydrogen production apparatus, the reformed gas is compressed by a compressor, and the reformed gas is stabilized at a predetermined pressure by a buffer tank, for example, and is sent to the PSA apparatus, where hydrogen is generated and off-gas is produced. It is supplied to the burner of the reformer and burned. Hydrogen purified by the PSA unit is hydrogen of a purity that meets standards as a product.

By the way, the reformed gas sent to the PSA device is compressed to a predetermined pressure, so that a high-purity hydrogen product can be obtained, so the compression capacity of the compressor is an important factor.

Patent Literature 1 describes a method of supplying a source gas to a PSA device in which pressure fluctuations in the source gas to be supplied to the PSA device are suppressed and the source gas compressor is kept in a relatively steady state of continuous operation.

In Patent Document 1, a raw material gas compressor is provided in order to raise the pressure of the raw material gas supplied from the raw material gas receiving line to the PSA apparatus to a required pressure. A path is constructed to receive the raw material gas into the receiving tank, and when the PSA apparatus receives a large amount of gas, a normal supply path and a path to supply the raw material gas pressurized in the raw material gas receiving tank to the PSA apparatus are constructed. .

In Patent Document 2, when the temperature measurement value of the reformer exceeds a predetermined set value determined from the viewpoint of heat resistance of the reformer, the measured value of the pressure gauge that measures the discharge pressure of the compressor Based on this, it is described that the discharge pressure of the compressor is controlled to increase, the hydrogen yield in the PSA is improved, and the temperature of the reformer is lowered below the set value.

Japanese Patent Application Laid-Open No. 2001-205030 JP-A-2000-281308

Here, parts constituting the compressor, particularly consumable parts such as sealing materials, are items to be inspected in periodic inspections, and need to be replaced as appropriate.

However, if the replacement of expendable parts such as sealing material is delayed, the airtightness of the compressor cannot be maintained. If the service life of consumable parts is fixed, they can be replaced periodically. This makes daily inspections by workers difficult.

Also, if the consumables are replaced after they have reached the end of their service life, the production of hydrogen during the replacement work will be delayed.

SUMMARY OF THE INVENTION An object of the present invention is to obtain a hydrogen production apparatus, a hydrogen production method, and a compressor life monitoring control program that can steadily stabilize the pressure of the reformed gas fed to the PSA apparatus.

A hydrogen production apparatus according to the present invention includes a reformer for steam reforming a feedstock hydrocarbon and releasing a reformed gas, and a compressor for adjusting the pressure of the reformed gas released from the reformer to a predetermined pressure. and a hydrogen purifier that receives the reformed gas discharged from the compressor and separates it into off-gas and hydrogen to purify hydrogen, wherein the reformed gas in the compressor an acquisition unit that acquires state information during hydrogen production that changes in correlation with the adjustment pressure of the compressor, and a determination unit that determines an abnormality in the compression capacity of the compressor based on the transition of the state information acquired by the acquisition unit. and the hydrogen purifier includes a pressure monitoring device for monitoring the pressure of the reformed gas received, and is triggered by a detected value of the pressure monitoring device, and alternately switches between pressurization and depressurization to perform the reforming. Off-gas containing carbon dioxide gas, carbon monoxide, and hydrocarbons is removed from the raw gas to separate and concentrate hydrogen, and the state information acquired by the acquisition unit is detected by the pressure monitoring device, and the hydrogen purifier It is a differential value of the detected value that changes periodically depending on the hydrogen refining in the determination unit, and the differential value of the detected value is a normal initial stage value and a gradual decrease in pressurization capacity. It is characterized in that it continuously compares the value of each step .
Further, in the present invention, the determination unit extracts, as the state information, a peak value of pressure control that periodically changes due to the compressor from the differential value of the detected value .

According to the present invention, the acquisition unit acquires the state information during hydrogen production that changes in correlation with the regulated pressure of the reformed gas in the compressor. The judging means judges whether the compression capacity of the compressor is abnormal based on the transition of the state information acquired by the acquisition unit.

In other words, even if the pressure in the compressor is not directly detected, it is possible to recognize, for example, the time to replace consumables before the end of the life of the compressor. Work such as replacement of consumables can be performed while the operation is suspended. Incidentally, the hydrogen purification device is not limited to the PSA device.

The PSA apparatus is preliminarily provided with a pressure monitoring device for monitoring the pressure, and is used, for example, as a trigger for switching between pressurization and depressurization of the absorbent. State information (historical data of pressure change) obtained from this pressure monitoring device can be used as state information for life determination of the compressor.

The present invention is characterized in that the determination unit analyzes the transition of the state information, identifies when the compression capacity of the compressor is abnormal from the transition of the state information after the present, and predicts the life of the compressor. there is

The judging unit analyzes the transition of the state information, identifies when the compression capacity of the compressor is abnormal based on the transition of the state information after the present, and predicts the life of the compressor.

In the method for producing hydrogen according to the present invention, the reformer steam-reforms the feedstock hydrocarbon to release a reformed gas, and the compressor adjusts the reformed gas released from the reformer to a predetermined pressure. 1. A hydrogen production method in which a hydrogen purifier receives the reformed gas discharged from the compressor and separates it into an off-gas and hydrogen to purify hydrogen, wherein the hydrogen purifier receives the reformed gas. A pressure monitoring device for monitoring pressure is provided, and pressurization and depressurization are alternately switched using a detection value of the pressure monitoring device as a trigger to remove off-gas containing carbon dioxide, carbon monoxide, and hydrocarbons from the reformed gas. Hydrogen is separated and concentrated by removal, and is detected by the pressure monitoring device as status information during hydrogen production that changes in correlation with the regulated pressure of the reformed gas in the compressor, and hydrogen in the hydrogen purifier A differential value of the pressure that changes periodically depending on the refinement is obtained, and a normal initial stage and a stage in which the pressurization capacity gradually decreases are continuously performed in the obtained differential value of the pressure. It is characterized by comparing and judging abnormality of the compression capacity of the compressor.

The present invention is characterized in that a peak value of pressure control that periodically changes due to the compressor is extracted as the state information from the differential value of the detected value .

In the present invention, the judgment is characterized in that the transition of the state information is analyzed, and from the transition of the state information after the present, a time when the compression capacity of the compressor is abnormal is specified, and the service life is predicted. .

A compressor life monitoring control program of the present invention is characterized by causing a computer to function as an acquisition unit and a determination unit.

As described above, according to the present invention, the life of the compressor can be determined based on the state information related to hydrogen production. Replacement work, etc. can be performed.

As described above, according to the present invention, the pressure of the reformed gas fed to the PSA apparatus can be steadily stabilized.

1 is a schematic diagram showing the configuration of a hydrogen production apparatus according to an embodiment; FIG. FIG. 4 is a functional block diagram showing a life monitoring control unit that monitors the life of a compressor, which is executed by the MCU according to the present embodiment; 4 is a flow chart showing a preheating control routine according to the present embodiment; (A) is a pressure-adsorption rate characteristic diagram for each gas component, and (B) is a pressure control timing chart for hydrogen purification in a PSA apparatus.

As shown in FIG. 1, the hydrogen production apparatus 10 includes a reformer 12, a pre-pressurization water separation section (drain tank) 14, a compressor 16, a post-pressurization water separation section (drain tank) 18, and a PSA ( and a Pressure Swing Adsorption) device 20 .

PSA device 20 is an example of the hydrogen purifier of the present invention. The hydrogen production apparatus 10 produces hydrogen from a hydrocarbon feedstock, and in this embodiment, a case where city gas containing methane as a main component is used as an example of the hydrocarbon feedstock will be described.

(Reformer 12)

The reformer 12 has a plurality of spaces partitioned by a plurality of cylindrical walls concentrically arranged with different diameters (multiple cylindrical shape). A space is formed, with the inner two layers communicating at the lower end and the outer two layers communicating at the upper end.

The spaces are, in order from the inside, a combustion chamber, a flue gas channel, a preheating channel, and a reformed gas channel. The structure of the multiple cylindrical reformer of the present embodiment is an example, and the structure is not limited.

A burner is placed in the combustion chamber, city gas or off-gas is supplied as fuel, mixed with air in the combustion chamber and combusted, flue gas is guided to the flue gas flow path, and flows into the preheating flow path as a raw material. city gas and reforming water are preheated to produce a mixed gas.

The preheating channel is provided with a spiral member on the upstream side and a reforming catalyst layer on the downstream side. The mixed gas receives heat from the flue gas flowing through the flue gas flow path while moving helically by the helical member, and then undergoes a steam reforming reaction in the reforming catalyst layer, resulting in a reformed gas containing hydrogen as a component. G1 is generated.

The reformed gas is included in the reformed gas by passing through the CO conversion catalyst layer (and the CO selective oxidation catalyst layer as necessary) when passing through the reformed gas flow channel, which is the space of the outermost layer. Carbon monoxide and water vapor react to convert to hydrogen and carbon dioxide, and are discharged as reformed gas G2 with reduced carbon monoxide. In the above description, a structure in which the reforming catalyst layer and the CO conversion catalyst tank are integrated is assumed, but a structure in which the reforming catalyst layer and the CO conversion catalyst tank are not integrated is also possible.

The reformer 12 is connected to a pre-pressurization water separator (drain tank) 14 via a flow pipe 22 . The reformed gas G2 flowing out of the reformer 12 is mixed with the cooling water in the cooling pipe of the liquid chamber (chiller) 26 in the heat exchange section 24 (referred to as "HEx" as an abbreviation for Heat Exchanger in FIG. 1). and flows into the pre-pressurization water separation section 14 .

The pre-pressurization water separation unit 14 has a gas chamber in the upper portion and a liquid chamber in the lower portion. In the reformed gas G2 that has flowed into the gas chamber of the pre-pressurization water separation section 14, water is condensed, separated, and stored.

The stored water is sent to the water recovery pipe 15 and returned to the reformer 12 as reforming water by driving a pump (not shown).

The pre-pressurization water separation section 14 is connected to the compressor 16 via a flow pipe 28 . The reformed gas G<b>3 in which water is separated from the reformed gas G<b>2 in the pre-pressurization water separation section 14 flows into the compressor 16 . A buffer tank 30 is interposed in the passage pipe 28, and the reformed gas G3 flows into the compressor 16 in a state in which the pressure (for example, atmospheric pressure) is stabilized in the buffer tank 30.

The compressor 16 compresses the reformed gas G3 supplied from the pre-pressurization water separation section 14 with a pump (not shown). The compressor 16 is cooled by, for example, public water (city water 32).

The compressor 16 is connected to a post-pressurization water separator (drain tank) 18 via a flow pipe 34 . The reformed gas G4 compressed by the compressor 16 is cooled in the heat exchange section 36 by heat exchange with cooling water in the cooling pipe of the liquid chamber (chiller) 38, and flows into the water separation section 18 after being pressurized.

The post-pressurization water separation unit 18 has an upper gas chamber and a lower liquid chamber. The reformed gas G4 that flows into the gas chamber of the water separator 18 after being pressurized has water condensed and separated, and is stored.

The stored water is sent to the water recovery pipe 19 and returned to the reformer 12 as reforming water by driving a pump (not shown).

The post-pressurization water separation unit 18 is connected to a buffer tank 42 via a channel pipe 40 , and the reformed gas G5 in which water is separated from the reformed gas G4 in the post-pressurization water separation unit 18 is sent to the buffer tank 42 . flow into

The buffer tank 42 accumulates the reformed gas G5 supplied from the post-pressurization water separator 18 . The buffer tank 42 is connected to the PSA device 20 via a flow pipe 44 , and the reformed gas G 5 once accumulated in the buffer tank 42 and kept at a constant pressure flows into the PSA device 20 .

(PSA device 20)

In the PSA device 20, the reformed gas G5 is separated into impurities (off-gas containing combustible gas) and hydrogen by pressure control (see FIG. 4) (hydrogen refining). The purified hydrogen is delivered to the hydrogen supply pipe 46, stored in a tank (not shown), or sent to a hydrogen supply line.

The principle of hydrogen refining with the PSA device 20 will be described with reference to FIG.

As shown in FIG. 4A, when the pressure is high, hydrogen passes through without being adsorbed, but other gas components (carbon dioxide, methane, carbon monoxide, etc.) are adsorbed. High-purity hydrogen can be produced by maintaining the pressure.

On the other hand, when the pressure is low, all gas components including hydrogen are not adsorbed and pass through. Since this does not become a refined hydrogen product, it is passed to the buffer tank 42 as offgas. That is, the gas components adsorbed when the pressure is high are removed, and the ability to adsorb gas components other than hydrogen is restored.

Therefore, as shown in FIG. 4B, in the PSA device 20, by repeatedly increasing and decreasing the pressure (pressure control), hydrogen refining in the PSA device 20 can be continued.

As a reference, the following forms can be mentioned as the form of transportation of the product hydrogen after being sent to the hydrogen supply pipe 46 .

(1) High pressure gas

For example, if hydrogen is to be used in a fuel cell vehicle, it is necessary to increase the pressure to 70 MPa or higher, so transportation using a permissible high-pressure gas is effective.

(2) Liquid hydrogen

Hydrogen liquefies at −235° C. and its volume is reduced to 1/800, making it suitable for transportation.

(3) Organic hydride

By combining hydrogen with an organic substance such as toluene and transporting (or storing) it in the form of an organic hydride, the volume can be reduced to about 1/600 of that of a normal gas.

(4) Pipeline

It can be mailed by pipeline in the same way as city gas.

As shown in FIG. 1, the off-gas other than hydrogen separated by the PSA device 20 flows through the combustible gas supply pipe 48 and is supplied as fuel to the burner provided in the combustion chamber of the reformer 12 .

That is, the combustible gas supply pipe 48 is provided with an offgas buffer tank 50 . The offgas is supplied from the PSA device 20 to the offgas buffer tank 50 through the combustible gas supply pipe 48 and accumulated therein. On-off valves 50A and 50B are attached to the upstream side and downstream side of the offgas buffer tank 50 to control the inflow and outflow of offgas to the offgas buffer tank 50 .

A flow rate adjusting section 52 is provided on the downstream side of the offgas buffer tank 50 . The flow rate adjusting unit 52 adjusts the flow rate of supplying the off-gas accumulated in the off-gas buffer tank 50 to the reformer 12 .

The capacity of the offgas buffer tank 50 is set in consideration of the balance between the amount of offgas sent from the PSA device 20 and the amount of offgas supplied to the burner, the pressure inside the offgas buffer tank 50, and the like.

On the other hand, the flue gas after being burned in the combustion chamber of the reformer 12 is guided from the flue gas flow path to the gas discharge pipe 54, and in the heat exchange section 56, the cooling water in the cooling pipe of the liquid chamber (chiller) 58 and the is cooled by heat exchange, flows into a combustion exhaust gas water separator (drain tank) 60, water is stored, and the exhaust gas is discharged from an exhaust pipe 62 to the outside.

The stored water is sent to the water recovery pipe 64 and returned to the reformer 12 as reforming water by driving a pump (not shown).

The chillers 26, 38, and 58 applied to the heat exchange units 24, 36, and 56 installed at various locations may be of a single configuration and share the refrigerant.

(Reformed gas pressure by compressor 16)

By the way, the reformed gas fed into the PSA device 20 is compressed to a predetermined pressure, and by maintaining the predetermined pressure, a high-purity hydrogen product can be obtained. Therefore, in order to maintain the compression capacity of the compressor 16, the parts constituting the compressor 16, especially consumable parts such as sealing materials, should be included in periodic inspections and replaced as appropriate. In other words, the airtightness of the compressor 16 cannot be maintained if the replacement of expendable parts such as the sealing material is delayed.

For this reason, daily inspections are desired, but daily inspections by workers are difficult from the standpoint of work efficiency. In addition, in order to automatically monitor the pressure of the reformed gas G4 compressed by the compressor 16, a pressure sensor or the like for detecting the pressure of the reformed gas G4 is required separately, resulting in an increase in the number of parts.

Therefore, in the present embodiment, a device (pressure sensor 66) provided in advance in the PSA apparatus 20 is used to monitor the pressure of the reformed gas G4 compressed by the compressor 16. .

Problems in applying the pressure sensor 66 provided in advance in the PSA device 20 include the following.

Flow pipes 34, 40, and 44 for supplying the reformed gas G4 output from the compressor 16 to the PSA device 20 are provided with a heat exchange section 36, a buffer tank 42, and a post-pressurization water separation section 18. there is That is, since the reformed gas G4 passes through the heat exchange section 36, the buffer tank 42, and the post-pressurization water separation section 18, the pressure of the reformed gas G4 is different from the pressure of the reformed gas G5 received by the PSA device 20. .

Therefore, in the present embodiment, the pressure detection values taken in from the pressure sensor 66 provided in the PSA device 20 are accumulated and stored, and the life of the compressor 16 is estimated based on the time-dependent change state (pressure change rate) based on the date and time information. was determined.

More specifically, even if the pressure change (pressure drop) is smaller than the pressure fluctuation of the reformed gas G4 discharged from the compressor 16 and is within the allowable range for the PSA device 20, the pressure detected by the pressure sensor 66 , that is, the slope (pressure change rate) that changes with time (the degree of change may be amplified), the pressurization capability of the compressor 16 is monitored. As a result, it is possible to continuously compare the initial stage in which the compressor 16 has a normal pressurizing ability and the stage in which the pressurizing ability gradually decreases due to deterioration of consumable parts, etc. The pressurization capacity required to purify hydrogen above a predetermined purity can be monitored.

When the pressure sensor 66 provided in advance in the PSA device 20 is applied as in this embodiment, the pressure control in the PSA device changes depending on the hydrogen refining (periodic pressure shown in FIG. 4B). change).

Therefore, as an example, as shown in FIG. 4B, by extracting the peak value of the pressure control that changes periodically and monitoring the state (pressure change) in which the peak value gradually decreases, compression The life of machine 20 can be determined.

It should be noted that the monitoring is not limited to the peak value, and the pressure value may be extracted at regular intervals. It is also possible to monitor changes in the area of .

FIG. 2 is a functional block diagram of life monitoring control section 68 for monitoring the life of compressor 16 according to the present embodiment. It should be noted that each block in FIG. 2 is a block classification of the functions required for life monitoring, and does not limit the hardware configuration.

The life monitoring control unit 68 functions as part of an MCU (machine control unit) 70 that controls the entire hydrogen production apparatus 10 . The life monitoring control unit 68 may be configured with a preheating control program stored in advance in the non-volatile memory of the MCU 70, or may be an ASIC or the like in which a program for executing preheating control is incorporated in an IC chip. Furthermore, a control board having a hardware configuration in which electronic components such as relays and diodes assembled based on a logic circuit are arranged in a predetermined wiring pattern may be used.

The pressure sensor 66 provided in the PSA device 20 and the life monitoring control section 68 are connected to the pressure information acquisition section 72 .

Based on the date and time information managed by the date and time information management unit 74, the pressure information acquisition unit 72 acquires the signal from the pressure sensor 66 at a predetermined time (pressurization time in the PSA device 20), and performs cumulative processing. Stored in database 78 by unit 76 .

The date/time information manager 74 is connected to the pressure change rate calculator 80 . The date/time information management unit 74 instructs the pressure change rate calculation unit 80 to perform life determination of the compressor 16 for each predetermined period.

Upon receipt of the life determination instruction, the pressure change rate calculation unit 80 takes in the pressure information accumulated in the past fixed period from the database 78 and calculates the change rate of the pressure information. Since pressure fluctuations are suppressed by the buffer tank 30 or the like in the PSA device 20, the calculated rate of change may be amplified.

The pressure change rate calculation unit 80 is connected to the comparison unit 82 and sends the calculation result to the comparison unit 82 .

The comparison unit 82 reads the threshold value from the threshold value storage unit 84 and compares it. A result of comparison by the comparison unit 82 is sent to the life determination unit 86 . Based on the comparison result, the life determination unit 86 notifies the outside of the pressure abnormality via the output unit 88 .

Note that the life determination unit 86 determines the life based on the comparison result of the comparison unit 82, but instead of taking in the result of one time, for example, the comparison result of a plurality of times, the pressure change rate continuously exceeds the threshold value. If it is, it is judged as abnormal (example 1). In other words, since sudden pressure fluctuations are not abnormal due to lifespan, it is preferable to give some time to the abnormality determination. Sudden pressure fluctuations may be reported separately.

In addition, the life determination unit 86 may perform machine learning based on the huge amount of information about the pressure change rate stored in the database 78 and the comparison result, and predict the future life of the compressor 16 (for example, 2).

The operation of this embodiment will be described below.

First, the general flow of the hydrogen production process by the hydrogen production device 10 will be described.

City gas is supplied to the reformer 12 . The city gas supplied to the reformer 12 is heated while being mixed with water for reforming in the preheating channel of the reformer 12, and is supplied to the reforming catalyst layer. In the reforming catalyst layer, a reformed gas G1 containing hydrogen as a main component is generated by a steam reforming reaction of the mixed gas upon receiving heat from the flue gas flowing through the flue gas passage. The reformed gas is supplied to the CO conversion catalyst layer through the reformed gas channel. In the CO conversion catalyst layer, carbon monoxide contained in the reformed gas reacts with water vapor to be converted into hydrogen and carbon dioxide, thereby reducing carbon monoxide.

Furthermore, the reformed gas that has passed through the CO conversion catalyst layer is supplied to the CO selective oxidation catalyst layer together with the oxidizing gas (air) supplied from the oxidant gas supply pipe, and the CO conversion catalyst layer (and CO selective By passing through the oxidation catalyst layer), the carbon monoxide and water vapor contained in the reformed gas react with each other, are converted into hydrogen and carbon dioxide, and are discharged as a reformed gas G2 with reduced carbon monoxide. . The reformed gas G2 is delivered to the flow pipe 22 .

The reformed gas G2 is supplied to the pre-pressurization water separation section 14 via the flow pipe 22 . In the pre-pressurization water separation unit 14 , the water condensed by cooling due to heat exchange in the heat exchange unit 24 is stored and sent to the water recovery pipe 15 . The reformed gas G3 from which water has been separated flows through the flow pipe 28 via the buffer tank 30, is supplied to the compressor 16, and is compressed by the compressor 16. FIG.

The compressed reformed gas G4 flows through the flow pipe 34 and is supplied to the water separator 18 after being pressurized. In the post-pressurization water separation section 18 , water condensed by cooling due to heat exchange in the heat exchange section 36 is stored and sent to the water recovery pipe 19 . The reformed gas G5 from which water has been separated flows through the flow pipe 40 via the buffer tank 42 and is supplied to the PSA device 20 .

In the PSA device 20 , the reformed gas G 5 is separated into off-gas, which is an impurity, and hydrogen by pressure control (see FIG. 4 ), and the hydrogen is sent to the hydrogen supply pipe 46 . The sent hydrogen is stored in a tank (not shown) or sent to a hydrogen supply line.

The off-gas containing impurities other than hydrogen flows into the off-gas buffer tank 50 through the combustible gas supply pipe 48 . The off-gas stored in the off-gas buffer tank 50 is adjusted in flow rate by the flow rate adjusting section 52 and supplied to the burner of the reformer 12 .

In the combustion chamber of the reformer 12 , the off-gas is combusted, and the combustion exhaust gas is supplied to the combustion exhaust gas water separator 60 through the gas discharge pipe 54 . Water contained in the flue gas is cooled and condensed by heat exchange in the heat exchange section 56 , stored in the flue gas water separation section 60 , and delivered to the water recovery pipe 64 . The combustion exhaust gas from which the water has been separated flows through the exhaust pipe 62 and is discharged to the outside.

FIG. 3 is a flow chart showing a life determination control routine for compressor 16 according to the present embodiment.

In step 100, date and time information is acquired, and then the process proceeds to step 102, in which pressure information detected by the pressure sensor 66 provided in the PSA device 20 is taken in at an appropriate time during the pressurization period in the PSA device 20, and step 104.

At step 104 , the date and time information and the pressure information are associated and accumulated in the database 78 , and the process proceeds to step 106 .

In step 106, it is determined whether or not it is time to determine the life of the compressor 16. If the determination is negative, the process proceeds to step 100 and the above steps are repeated.

In step 106, the life determination timing is set, but the life and the like may be determined immediately after the replacement of the consumables or at an early time immediately after the replacement.

For example, the service life of a consumable part is set to L hours (for example, L=1000 hours) after the start of use of a new consumable part, and the life judgment time is set to x hours (for example, x=200 hours) before L hours. If this is the case, there may be a delay in determining when the performance has deteriorated to the same level as the life before y hours (x<y, e.g., y = 900 hours) before L hours (e.g., delay in finding defective products, etc.) .

For this reason, if an algorithm that constantly monitors consumable parts immediately after replacement is adopted, it can be applied to monitoring of sudden failures (pressure drop) including defects in addition to the service life.

Further, if the determination in step 106 is affirmative, the process proceeds to step 108 to read the pressure information for a certain period accumulated in the database 78, and then to step 110 to calculate the pressure change rate (dP/dt). and go to step 112 .

At step 112, a threshold value for comparing the pressure change rate is read out, the process proceeds to step 114, the pressure change rate is compared with the threshold value, and the process proceeds to step 116. FIG. In step 116, life judgment is performed based on the comparison result.

In the life determination in step 116, for example, when the pressure change rate exceeds the threshold continuously from the results of comparison, not from the result of one comparison, for example, it is determined to be abnormal.

That is, it is determined whether or not there is a possibility that a pressure drop that affects the purity of the hydrogen purified by the PSA device 20 will occur within a predetermined period (Example 1).

In addition, machine learning is performed on pressure fluctuation trends, comparison results, etc. based on a huge amount of pressure information stored in the database 78, not simply from the results of multiple comparisons, to accurately predict the life of the compressor 16. (Example 2).

In the next step 118, it is determined whether or not the compressor 16 has reached the end of its life. If the determination is negative, the process returns to step 100 and repeats the above steps.

If the determination in step 118 is affirmative, the process proceeds to step 120 to notify the life of the compressor 16 (replacement of consumables, etc.), and the process proceeds to step 122 .

At step 122, it is determined whether or not a history indicating that the consumables have been replaced has been acquired. If the determination is affirmative, the process proceeds to step 124, the notification is cleared, and this routine ends.

As described above, in the present embodiment, the deterioration of the compression capacity due to the life of the compressor 16, especially the life of consumable parts such as sealing materials, does not affect the purity of the hydrogen purified by the PSA device 20. In view of the influence (see FIG. 4), using existing equipment (using the pressure sensor 66 provided in advance in the PSA device 20), the compression capacity of the compressor 16 is monitored, and the life is monitored. Maintenance such as replacement of consumables can be reliably performed before the purity of hydrogen refined by the PSA device 20 is affected.

In this embodiment, the pressure sensor 66 provided in the PSA device 20 is used to monitor the compression capacity of the compressor 16 .

The pressure sensor 66 is an example of means for acquiring pressure information among means for acquiring state information of the present invention. Acquisition of pressure information is not limited to the pressure sensor 66, and other existing pressure sensors may be used.

Moreover, although the state information is pressure information (in the above description, the pressure sensor 66 is applied), a flow rate sensor, a temperature sensor, or the like may be used as a device for obtaining state information, not limited to pressure information.

G1 to G5 reformed gas 10 hydrogen production device 12 reformer 14 pre-pressurization water separation unit 15 water recovery pipe 16 compressor 18 post-pressurization water separation unit 19 water recovery pipe 20 PSA device (hydrogen purifier)
22 flow pipe 24 heat exchange section 26 liquid chamber 28 flow pipe 30 buffer tank 32 city water 34 flow pipe 36 heat exchange section 38 liquid chamber (chiller)
40 Flow pipe 42 Buffer tank 44 Flow pipe 46 Hydrogen supply pipe 48 Combustible gas supply pipe 50 Off gas buffer tank 50A, 50B On-off valve 52 Flow control unit 54 Gas discharge pipe 56 Heat exchange unit 58 Liquid chamber (chiller)
60 Combustion exhaust gas water separator (drain tank)
62 exhaust pipe 64 water recovery pipe 66 pressure sensor (pressure monitoring device)
68 life monitoring control unit 70 MCU
72 Pressure information acquisition unit (acquisition unit)
74 Date and time information management unit (acquisition unit)
76 accumulation processing unit (acquisition unit)
78 database (acquisition part)
80 Pressure change rate calculation unit (judgment unit)
82 comparison unit (determination unit)
84 threshold storage unit (determination unit)
86 life judgment unit (judgment unit)
88 Output section

Claims (7)

A reformer for steam reforming the feedstock hydrocarbon and releasing a reformed gas, a compressor for adjusting the pressure of the reformed gas released from the reformer to a predetermined pressure, and the a hydrogen purifier that receives a reformed gas and separates it into an off-gas and hydrogen to purify hydrogen,
an acquisition unit that acquires state information during hydrogen production that changes in correlation with the regulated pressure of the reformed gas in the compressor;
a determination unit that determines an abnormality in the compression capacity of the compressor based on the transition of the state information acquired by the acquisition unit ;
The hydrogen purifier includes a pressure monitoring device for monitoring the pressure of the received reformed gas, and is triggered by a detection value of the pressure monitoring device, and alternately switches between pressurization and depressurization to convert the reformed gas to carbon dioxide gas. , carbon monoxide, and off-gases containing hydrocarbons are removed to separate and concentrate hydrogen,
The state information acquired by the acquisition unit is a differential value of the detected value detected by the pressure monitoring device and periodically changing depending on hydrogen purification in the hydrogen purifier,
The hydrogen production apparatus , wherein the determination unit continuously compares a differential value of the detected value in a normal initial stage with a value in a stage in which the pressurization capability gradually decreases . 2. The hydrogen production apparatus according to claim 1, wherein said determination unit extracts, as said state information, a peak value of pressure control that periodically changes due to said compressor from a differential value of said detected value. 2. The judging unit analyzes the transition of the state information, identifies when the compression capacity of the compressor is abnormal based on the transition of the state information after the present, and predicts the life of the compressor. Or the hydrogen production apparatus according to claim 2. The reformer steam-reforms the feedstock hydrocarbon to release the reformed gas, the compressor adjusts the reformed gas released from the reformer to a predetermined pressure, and the hydrogen purifier removes the gas from the compressor. A hydrogen production method for receiving the discharged reformed gas and separating it into off-gas and hydrogen to purify hydrogen,
The hydrogen purifier includes a pressure monitoring device for monitoring the pressure of the received reformed gas, and is triggered by a detection value of the pressure monitoring device, and alternately switches between pressurization and depressurization to convert the reformed gas to carbon dioxide gas. , carbon monoxide, and off-gases containing hydrocarbons are removed to separate and concentrate hydrogen,
Pressure detected by the pressure monitoring device and periodically changing depending on hydrogen purification in the hydrogen purifier as status information during hydrogen production that changes in correlation with the regulated pressure of the reformed gas in the compressor. get the differential value of
Continuously comparing a normal initial stage and a stage in which the pressurization capacity gradually decreases in the obtained differential value of the pressure to determine an abnormality in the compression capacity of the compressor;
A hydrogen production method characterized by: 5. The method for producing hydrogen according to claim 4, wherein a peak value of pressure control that periodically changes by said compressor is extracted as said state information from the differential value of said detected value. 5. In the determination, transition of the state information is analyzed, and from the transition of the state information after the present, a time when the compression capacity of the compressor is abnormal is specified, and the life is predicted. The method for producing hydrogen according to claim 5. the computer,
Functioning as the acquisition unit and determination unit according to any one of claims 1 to 3,
Compressor life monitoring control program.

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