JPH07206401A - Control method of hydrogen producing apparatus and its device - Google Patents

Abstract

PURPOSE:To improve stability and durability by setting the purity of hydrogen and controlling its production amt., raw material flow rate, steam quantity to a reforming furnace, outlet temp., etc., to produce hydrogen. CONSTITUTION:This hydrogen producing apparatus is obtd. by locating a raw material hydrocarbon supplying section 1, steam reforming section 3, flow lines L1, L2, etc. Next, (A) a desired hydrogen purity is set and the hydrogen production amt. is set according to the required amt. of the hydrogen having the desired purity. Next, (B) the raw material flow rate to the reforming furnace 3 is controlled in accordance with the production amt. of A by a raw material flow rate controller FCO0 and simultaneously, (C) the anticipated hydrogen producing amt. 6 anticipated by the flow rate of B is calculated. The steam quantity is then controlled by a steam flow rate controller FC1 in such a manner as to attain the steam/ carbon ratio meeting the (C) production amt. 6. Next, (D) the outlet temp. of reforming furnace is controlled by a controller TC2 so as to meet the anticipated hydrogen production quantity 6 described above an keep up hydrogen purity A at set value, by which the hydrogen is so controlled as to be delivered to a hydrogen consumption plant, etc., from the hydrogen supplying section 5 via the line L6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a hydrogen production apparatus and the apparatus therefor, and more particularly to a hydrogen production apparatus for producing hydrogen by steam reforming a raw material hydrocarbon with a required amount of hydrogen and a predetermined hydrogen purity. And a device for controlling the same. In particular, the temperature of the steam reforming furnace outlet and the steam / carbon ratio are set according to the required hydrogen production amount to control the amount of steam and the amount of fuel to be supplied to the reforming furnace, thereby determining the hydrogen purity. The present invention relates to a control method and a device for a hydrogen production device, which is characterized by holding the value.

[0002]

2. Description of the Related Art A method for producing hydrogen by steam reforming using hydrocarbons such as naphtha, C ₄ fraction hydrocarbon, and recovered gas as a raw material is well known. Hydrogen production by this steam reforming is mainly carried out using a hydrogen producing apparatus composed of a desulfurization section, a steam reformer, a decarbonation section, a methanation section, etc. Hydrogen products will be supplied according to the demands of the customers of various plants that use hydrogen. In this case, it is desirable to immediately change the amount of hydrogen produced in response to changes in the required amount at the demand destination. On the other hand, hydrogen production equipment installed in various plants is generally large in size, and after increasing or decreasing the amount of raw materials to be supplied according to the demand of the hydrogen customer, there is a time delay before the increase or decrease appears as a change in the hydrogen content of the product. Is required to occur. Previously, this time lag was dealt with by predicting the fluctuation range of hydrogen consumption at the demand destination, constantly producing the maximum amount of hydrogen, and discharging surplus hydrogen to the outside. Thereafter, computer control was proposed, and a bleed hydrogen minimization method for controlling externally released hydrogen to a minimum as described in, for example, JP-A-63-55102 was proposed. Most of the hydrogen production equipment currently in operation are
This bleed hydrogen minimization control is adopted. This control method detects fluctuations in the amount of hydrogen consumed at the demand destination as fluctuations in the pressure of hydrogen flowing out of the production equipment, incorporates dead time compensation, and adjusts the raw material flow rate to the reforming furnace to release hydrogen. This is a method of controlling the amount to the minimum.

In the above-mentioned bleed hydrogen minimization control system, compared with the previous excess hydrogen release system, it is possible to suppress the production of useless hydrogen as much as possible, but the flow rate of the raw material to the reforming furnace fluctuates greatly. is what happened. If the raw material flow rate fluctuates greatly, the reforming furnace temperature also fluctuates greatly, and the hydrogen purity will fluctuate significantly. With respect to the fluctuation of the raw material flow rate, the steam amount to the reforming furnace is manually adjusted and controlled so that the steam / carbon (S / C) ratio becomes constant, and the outlet temperature of the reforming furnace is controlled. The fuel flow rate is manually adjusted to maintain a constant design value. Further, Japanese Patent Laid-Open No. 60-90802 proposes controlling these by a computer. But,
Even in the control of the steam amount and the fuel flow rate based on the fluctuation of the raw material flow rate, the fluctuation of the hydrogen purity cannot be avoided due to the delay of the adjustment time or the like, and it is difficult to maintain the hydrogen purity at a predetermined value.

On the other hand, fluctuations in hydrogen purity have a great influence on subsequent plants on the consumption side, and it is preferable to stabilize the fluctuations by minimizing the fluctuations. Conventionally, in order to keep the reaction temperature of the reforming furnace at a predetermined temperature so as to suppress fluctuations in hydrogen purity as much as possible, in addition to manually controlling the above-mentioned reforming furnace outlet temperature to a set value, etc. As an operator's know-how in operation, it was also taken measures such as gradually adjusting the fuel flow rate within the device design safety range while monitoring the reforming furnace outlet temperature according to the load fluctuation of hydrogen consumption. . However, keeping the hydrogen purity constant by such a method varies depending on the proficiency level of each operator, and further delay of the control system, delay of analyzer for measuring hydrogen purity, etc. There is performance and it is practically not easy.
Therefore, in order to prevent the hydrogen purity from falling below a certain value in practice, normally, high purity operation is performed so that the predetermined hydrogen purity is maintained at the maximum flow rate of produced hydrogen, and some fluctuations in hydrogen purity may occur. It is common to allow.

[0005]

However, in the above bleed hydrogen minimization control method, etc., setting the hydrogen purity higher than necessary increases the catalyst life in the reforming furnace due to excessive fuel consumption and temperature rise. There are problems such as shortening. Particularly, the catalyst used for steam reforming of hydrocarbons is preferably deteriorated at high temperature and operated at the lowest temperature possible. Therefore, it is preferable that the reforming furnace temperature in the reaction zone is set to the minimum range required to maintain the required reaction rate. In particular, when a decarbonator for removing carbon dioxide in the gas is provided in the downstream of the steam reforming furnace, most of the components other than carbon dioxide remain in the produced hydrogen gas, and the steam reforming furnace outlet Since the purity of hydrogen excluding carbon dioxide in the above is the same as the purity of hydrogen from the hydrogen production apparatus, it is desired that it can be controlled at the reforming furnace outlet.

Further, if the hydrogen purity fluctuates, it also affects the operation of hydrogen-consuming plants such as hydrocrackers and direct desulfurizers located downstream. That is, in these plant devices, most of the hydrogen from the hydrogen production device is circulated and consumed by the reaction, and the purity of the circulated hydrogen gas needs to be constant from the reaction side. However, fluctuations in hydrogen purity are not preferable. Furthermore, the amount of hydrogen consumed in the subsequent various plant devices varies not only with the amount of the object to be treated such as petroleum but also with its properties, and is often unpredictable in advance. In addition, hydrogen is often supplied to multiple hydrogen consumption devices by one hydrogen production device, and it is more difficult to predict the hydrogen consumption amount.Therefore, at the hydrogen production device design stage, the reformer outlet temperature is set uniformly. It is extremely difficult to control the hydrogen purity by using hydrogen.

In view of the conventional operation and control situation in which the purity of hydrogen flowing out from the hydrogen production apparatus fluctuates according to the hydrogen consumption of the downstream demand destination as described above, the present invention further Fluctuations in purity are not desirable for the hydrogen consuming plant side as well, and in consideration of the current situation where stabilization is desired, the hydrogen purity produced is maintained at a specified value even when there is a load variation on the hydrogen consuming device side. It is an object of the present invention to provide a method for controlling a hydrogen production device. At the same time, it aims to provide the device. The present inventors have completed the present invention as a result of earnestly studying various operating variables such as a raw material flow rate, a steam supply amount and a reforming furnace outlet temperature in a hydrogen production process operation for the above purpose.

[0008]

According to the present invention, in a hydrogen production apparatus for producing hydrogen by steam reforming raw material hydrocarbons, (1) the purity of hydrogen to be produced is set in advance, and Set the hydrogen production amount according to the required hydrogen amount,
(2) At the same time as controlling the flow rate of the raw material to the reforming furnace based on the set hydrogen production rate, (3) calculating the expected hydrogen production rate from the raw material flow rate controlled in the above, and (4) the expected hydrogen production rate. The steam amount to the reforming furnace is controlled so that the steam / carbon ratio matches the production amount, and (5) the hydrogen purity is adjusted to maintain the hydrogen purity at a predetermined set value while matching the expected hydrogen production amount. Provided is a method for controlling a hydrogen production device, which comprises controlling the temperature of a quality furnace outlet.

Further, the present invention provides a hydrogen producing apparatus for producing hydrogen by steam reforming raw material hydrocarbons,
(1) Raw material hydrocarbons supply section-desulfurization section-steam reforming furnace-decarbonation section-hydrogen supply section are connected in series by means of a distribution line. The desulfurization section-steam reforming furnace A raw material temperature detector, a raw material pressure detector, and a flow rate control valve are installed in the distribution line of the steam reforming furnace, and an outlet temperature detector, an inlet temperature detector, and a steam flow rate control valve from the steam supply section are provided in the steam reforming furnace. A steam line is provided and a fuel line having a fuel flow rate control valve from the fuel supply unit is provided, and a hydrogen pressure detector is provided at the hydrogen supply unit, and (2) the hydrogen pressure detection is performed. Reformer raw material flow rate control system for controlling the raw material flow rate at the steam reforming furnace inlet according to instructions from the reformer, hydrogen gas according to instructions from the reformer raw material flow rate control system, the raw material temperature detector and the raw material pressure detector Set according to expected manufacturing volume The steam amount control system for the reforming furnace that controls the steam supply amount of the steam reforming furnace based on the steam / carbon ratio that is set, and the reforming furnace outlet temperature that is set by the expected hydrogen gas production amount Provided is a hydrogen production device characterized in that a fuel supply amount control system for controlling a fuel flow rate is formed.

[0010]

The present invention is configured as described above, sets the purity of hydrogen to be produced in advance, determines the raw material flow rate according to the required amount of hydrogen of the set purity, and estimates the hydrogen production amount from the raw material flow rate. The steam / carbon (S / C) ratio in the steam reforming furnace, which is necessary to supply the expected hydrogen production amount in the production equipment, is dynamically set based on the characteristics of the hydrogen production equipment, and the set value is set. Based on this, the amount of steam added to the raw material hydrocarbons at the steam reforming furnace inlet is determined.
At the same time, the steam reforming furnace outlet temperature required to supply the expected hydrogen production amount is also dynamically changed and set,
A reforming furnace using a controller gain that is variable according to the expected hydrogen production amount and a feedforward signal that is determined from the raw material flow rate that is determined according to the required hydrogen amount so that the preset reformer outlet temperature is reached. Control the fuel flow to the. According to the present invention, by adopting the above control method, the S / C ratio and the outlet temperature of the reforming furnace are automatically controlled so as to maintain a predetermined hydrogen purity according to the fluctuation of the hydrogen consumption amount of the demand destination. can do.

Further, when there is a small fluctuation in the hydrogen consumption on the downstream side in the steady state, the displacement between the pressure detected by the pressure detector provided on the outlet side of the hydrogen production apparatus and the preset pressure value. To the value, the raw material flow rate on the steam reforming furnace inlet side, which is obtained by adding dead time compensation, is regulated and controlled, the expected hydrogen production amount is set from the controlled raw material flow rate, and is automatically controlled in the same manner as above, A predetermined hydrogen purity can be maintained. Therefore, in the hydrogen production device of the present invention,
By predicting the required hydrogen production amount by following changes in hydrogen consumption in sequence, the S / C ratio in the reforming furnace and the reforming furnace outlet temperature are continuously and dynamically set accordingly. The steam amount and fuel flow rate supplied to the quality furnace can be automatically controlled so as to always maintain a predetermined hydrogen purity.

[0012]

Embodiments of the present invention will be described in more detail with reference to the drawings. However, the present invention is not limited to the following examples. FIG. 1 is a schematic explanatory diagram of a hydrogen production apparatus for showing the configuration of an embodiment of the control method and apparatus of the present invention. In FIG. 1, raw material hydrocarbons containing butane (C ₄ ) gas containing a mixture of recovered gas and naphtha as a main component are circulated from a raw material hydrocarbons supply unit 1 through a line L1 and heated by a heating furnace (not shown). ) To flow into the desulfurization section 2,
After the sulfur content contained in the raw material hydrocarbons is removed,
It is supplied to the steam reforming section 3 through the line L2.
In the steam reforming unit 3, a predetermined amount of steam is supplied via the line L3, and the raw material supplied from the line L1 is steam-reformed to produce hydrogen. In this case, the thermal energy required for the reforming reaction of the endothermic reaction is supplied by burning the fuel fed into the reforming furnace burner via the line L4. The hydrogen produced in the steam reforming unit 3 removes carbon dioxide gas generated by steam reforming in the decarbonation unit 4 via a line L5, and then, from the hydrogen supply unit 5 to a demand destination via a line L6. It will be sent to the hydrogen consuming plant, etc.

Next, a description will be given of a control method in each operation unit and line when the hydrogen consumption amount of the demand destination plant fluctuates from the state in which the hydrogen production apparatus is operated in a predetermined steady state. First, a control method according to small fluctuations in hydrogen consumption in the hydrogen consumption device during steady-state operation will be described. In FIG. 1, the pressure detector P
Line L6 from the decarbonation unit 4 to the hydrogen supply unit 5 by I _1.
The hydrogen pressure at the PC is detected and the detected hydrogen pressure is detected by the hydrogen pressure controller PC ₁
And the displacement with respect to a predetermined pressure (designed steady-state hydrogen pressure) is calculated. After the dead time compensation is added to the calculated displacement value, the output is input to the raw material flow rate controller FC ₀ arranged on the line L2. The raw material flow controller FC ₀ is
The raw material flow rate control valve V ₀ is operated based on the raw material flow rate set value input from the hydrogen pressure controller PC ₁ and the input value from the raw material flow rate detector FI _0, and the raw material flow rate after desulfurization corresponds to the changed hydrogen consumption amount. To adjust and control. As described above, the reformer raw material flow rate control system C ₀ for controlling the raw material flow rate based on the fluctuation of hydrogen consumption in the subsequent hydrogen consuming plant or the like is formed.

[0014] On the other hand, the reformer feedstock flow rate detection value F _0, the reformer is arranged in the line L2 the material temperature detector TI ₀ and reformer feed pressure detector from the reformer feed flow detector FI ₀ P
I reformer feedstock detected temperature value T ₀ is detected respectively from ₀
And the detection values F ₀ based on reformer feed pressure detection value P _0,
By inputting T ₀ and P ₀ to the arithmetic and control unit 6, the expected production hydrogen amount H ₀ expected to be produced is calculated from the set value of the raw material flow rate supplied to the reforming furnace 3 which is regulated and controlled as described above. In this case, in the case of the raw material hydrocarbon composed of a plurality of components such as C ₄ fraction, recovered gas, and naphtha, the expected production hydrogen amount H ₀ is obtained by adding the physical property value obtained from the flow rate ratio of each constituent component.
Is calculated. Further, the characteristic data based on the hydrogen production device, the process and the like are inputted in advance to the arithmetic and control unit 6, and the calculated hydrogen production amount H ₀ and the previously inputted characteristic data are used as the expected hydrogen production amount H ₀ . The set value of the corresponding S / C ratio is calculated. The obtained set value of the S / C ratio and the S / C ratio calculated by the calculator 6 are input to the S / C controller XC ₁ , and the value based on them is input to the steam flow controller FC ₁
To enter. The steam flow controller FC ₁ operates the steam flow control valve V ₁ based on the input value to control and control the steam amount supplied to the reforming furnace 3 from the line L3. As described above, the reforming furnace supply steam amount control system C ₁ for controlling the steam supply amount to the reforming furnace based on the fluctuation of hydrogen consumption in the subsequent hydrogen consumption plant or the like is formed.

Further, similarly to the above, the expected hydrogen production amount H ₀ and the reforming furnace inlet temperature detected value T ₁ calculated from the reforming furnace raw material flow rate input to the arithmetic and control unit 6 and the characteristic data already input From this, the outlet temperature T ₂ of the reforming furnace 3 corresponding to the expected hydrogen production amount H ₀ and corresponding to the preset hydrogen purity is calculated. The obtained reformer outlet temperature set value T ₂ is input to the reformer outlet temperature controller TC _2, and at the same time, the detected outlet temperature measured value T ′ ₂ from the reformer outlet temperature detector TI ₂ is input to the reformer. It is input to the outlet temperature control meter TC ₂ , and based on the input, the reforming furnace outlet temperature control value controlled by the reforming furnace outlet temperature control meter TC ₂ is further calculated by the characteristic data previously input to the arithmetic and control unit 6. A variable controller gain X is added according to the calculated expected hydrogen production amount in the hydrogen production apparatus, and the value is input to the fuel flow controller FC ₂ .

Simultaneously with the inputs from the reforming furnace outlet temperature controller TC ₂ and the controller gain X, the fuel flow controller FC ₂ corresponds to the calculated outlet temperature T ₂ and has arithmetic control. The required fuel flow rate is calculated based on the reforming furnace raw material flow rate, the reforming furnace inlet temperature detection value T _{1 and the} like input to the device 6, and the required fuel flow rate calculation value is used as the fuel flow rate controller F
Enter in C ₂ . The fuel flow rate controller FC ₂ has both the values of the feedback control by the outlet temperature controller TC ₂ and the controller gain X and the feedforward control based on the above-mentioned required fuel flow rate calculated value, and the fuel flow rate detector FI.
_The fuel flow rate control valve V ₂ is operated based on the detected value from ₂ to control the fuel flow rate from the line L4 to the reformer burner. As described above, the reforming furnace outlet temperature control system C ₂ for controlling the temperature in the reforming furnace based on the fluctuation of the hydrogen consumption in the subsequent hydrogen consuming plant or the like is formed.

Unlike the above-mentioned slight fluctuations in the hydrogen consumption amount from the steady state, when it is desired to change the hydrogen production amount drastically or systematically, the required hydrogen production amount set value due to the fluctuation is used as the raw material flow rate control. It can be directly input to the total FC ₀ and can be controlled in the same manner as the above-described control of the small fluctuation in the steady state. In addition, similar to the above-mentioned slight fluctuation, the data of the predetermined hydrogen purity and the required hydrogen production amount are input to the arithmetic and control unit, and the flow rate value of the raw material hydrocarbons to the steam reforming furnace is corresponding to the input value. Input into the raw material flow rate control system FC ₀ , then
Similar to the above-mentioned control of small fluctuations in the steady state, the S / C value and the reforming furnace outlet temperature are variably set, and the reforming furnace supply steam amount and the fuel flow rate are respectively controlled based on them, thereby reducing the hydrogen consumption. The desired amount of hydrogen can be supplied with a preset hydrogen purity.

The present invention, as described above, provides for C ₀ , C ₁ and C
Incorporating three control systems ( ₂ ), the control system C ₀ controls the flow rate of the feedstock hydrocarbons at the same time, and at the same time controls the flowrate of the feedstock hydrocarbons, the hydrogen production amount is calculated from the feedstock hydrocarbons flow rate. Then, in the C ₁ control system, the steam amount to the reforming furnace is controlled so as to correspond to the planned hydrogen production amount and to correspond to the S / C ratio for satisfying the preset predetermined hydrogen purity. At the same time, in the control system C ₂ , the reforming furnace outlet temperature is controlled so as to correspond to the calculated hydrogen production amount and satisfy the preset predetermined hydrogen purity. Therefore, the S / C ratio and the reformer outlet temperature are continuously and dynamically controlled while always anticipating the hydrogen production amount of the preset hydrogen purity according to the change of the raw material flow rate based on the fluctuation on the hydrogen consumption side. These control systems are easy to use in the current control and instrumentation technology as described below, and
It is a system that can be automatically controlled easily, and hydrogen purity can be maintained at a predetermined set value without complicated manual control by an operator as in the above-described conventional hydrogen production apparatus.

Next, the basic structure of the system for automatically controlling the hydrogen production apparatus as described above by setting the S / C ratio and the reforming furnace outlet temperature from the expected hydrogen production amount will be described. FIG. 2 is a relationship diagram showing an example of the relationship between the operating load amount (hydrogen production amount), the steam reformer outlet temperature (solid line), and the reforming reaction tube outlet temperature (dotted line). In this case, the operation load amount, that is, the hydrogen production amount is the hydrogen supply line L in FIG.
6, the measured value from the hydrogen pressure detector PI ₁ installed at 6,
The steam reformer outlet temperature is a value calculated by a displacement value with respect to the hydrogen pressure set in the hydrogen pressure controller PC ₁ , and the steam reformer outlet temperature is a reformer outlet temperature detector arranged in the line L5. This is the value detected by TI ₂ .

In general, a large number of tubular reaction tubes filled with a catalyst are installed inside the steam reformer, and hydrocarbons as a raw material flow in from the upper end of each reaction tube together with the supplied steam. Each reaction tube is directly heated by the combustion gas of the fuel supplied to the reforming furnace burner from the outside of the tube, and hydrocarbons are reformed with steam while flowing downward to form hydrogen and carbon monoxide gas. Flow out from the lower end of the reaction tube. A large number of outlet pipes at the lower end of the reaction tubes of these reforming furnaces are gathered together to form a single pipe, which is taken out of the steam reformer. The steam reformer outlet temperature is a temperature measured downstream of the steam reformer. External heat is radiated through the pipe from the reaction tube outlet inside the steam reformer to the steam reformer outlet temperature measurement unit, so the steam reformer outlet temperature measured and detected is the actual temperature at the reformer reaction tube outlet. It becomes lower than the reforming reaction temperature. However, the temperature difference between the steam reformer outlet temperature and the reforming reaction tube outlet temperature can be estimated by estimating the heat radiation amount and the hydrogen production amount at that time. Therefore, by measuring the reforming furnace outlet temperature at TI ₂ , the relationship with the operating load at that time can be estimated, and the displacement from the controlled raw material flow rate with the expected hydrogen production amount can be calculated. The outlet temperature of the reforming furnace can be controlled based on the displacement value.

FIG. 3 is a relationship diagram showing an example of the relationship between the reforming reaction tube outlet temperature and the S / C ratio. In this case, the reforming reaction tube outlet temperature is a value estimated from the steam reformer outlet temperature as described above, and the S / C ratio is the operating load (expected hydrogen) at a predetermined reforming furnace outlet temperature. It is the ratio of the molar flow rate of steam supplied to the steam reformer inlet side to the molar flow rate of carbon atoms contained in the raw material hydrocarbons in the production amount). The amount of carbon atoms contained in the raw material hydrocarbons per unit flow rate can be obtained by periodically inputting a value analyzed off-line periodically to a predetermined arithmetic and control unit. By multiplying the amount of carbon atoms contained per unit flow rate by the flow rate of the raw material, the molar flow rate of carbon atoms contained in the raw material hydrocarbons can be obtained. As described above, the amount of steam supplied in response to the load fluctuation, that is, the fluctuation of the raw material flow rate based on the fluctuation of the hydrogen consumption amount, is the molar flow rate of the carbon atoms contained in the predetermined raw material hydrocarbons, as shown in FIG.
It can be obtained by multiplying the S / C ratio at. Therefore, by measuring the reforming furnace outlet temperature in TI ₂ , the steam flow rate can be controlled by the product of the S / C and the controlled raw material flow rate.

The relationships shown in FIG. 2 and FIG. 3 are in one embodiment for hydrogen purity of 97 mol%,
These relationships naturally change according to the hydrogen purity set in each operation, but also change according to various operating conditions such as the apparatus used and the type and activity of the catalyst to be charged. Further, the relationship shown in FIGS. 2 and 3 is that the reaction tube outlet temperature set by the reaction equilibrium of the reaction system composed of the raw material hydrocarbons and steam in the reforming furnace so that the hydrogen purity becomes a predetermined set value. The following various factors can be added to the amount of steam to be supplied and shown. That is, when the hydrogen production amount is reduced, the temperature of the catalyst layer can be lowered from the reaction equilibrium. Further, when the amount of hydrogen produced is small, the S / C ratio must be set high in order to evenly distribute the raw material hydrocarbons and steam in the catalyst tubes in the steam reformer. Furthermore, the reaction equilibrium rate to cope with the catalyst activity reduction, the characteristics of the hydrogen production device, the material characteristics, the reaction characteristics, the catalyst characteristics, etc., which should be applied to the heat balance in various decarbonation processes installed in the downstream of the steam reformer Characteristic data such as the relationship between the load and the reformer outlet temperature, the relationship between the load and the S / C ratio, and the relationship between the load and the process controller gain are calculated and controlled as final data considering various conditions. It can be used by inputting it to the device.

[0023]

As described above, the control method and the apparatus thereof according to the present invention automatically keep the hydrogen purity at a predetermined level even if the hydrogen consumption amount of the demanded hydrogen consuming device fluctuates. In addition, the S / C ratio and the reforming furnace outlet temperature, that is, the reforming reaction temperature are continuously varied, and the purity of hydrogen produced can be controlled to be constant. Therefore, the influence on the hydrogen consuming device can be minimized. At the same time as controlling to supply the required amount of hydrogen of a predetermined purity,
The temperature of the reforming furnace can be constantly controlled to the minimum required temperature for producing the supplied hydrogen amount, and the hydrogen producing apparatus does not cause problems such as excessive fuel consumption and catalyst deterioration in the conventional method. The stability and durability of are significantly improved, and they have excellent industrial practicality. Furthermore, a desired amount of hydrogen can be supplied while maintaining a predetermined purity even when the hydrogen consumption device side largely or intentionally changes the required hydrogen amount.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a hydrogen production device for showing a configuration of an embodiment of the present invention.

FIG. 2 is a relationship diagram showing an example of a relationship between an operation load amount (hydrogen production amount), a steam reformer outlet temperature, and a reforming reaction tube outlet temperature used in one embodiment of the present invention.

FIG. 3 is a relationship diagram showing an example of the relationship between the reforming reaction tube outlet temperature and the S / C ratio used in one example of the present invention.

[Explanation of symbols]

1 Raw material hydrocarbons supply part 2 Desulfurization part 3 Steam reforming part 4 Decarbonation part 5 Hydrogen supply part L1, L2, L3, L4, L5, L6 Distribution line C ₀ Raw material flow control system C ₁ Reformer supply steam amount Control system C ₂ Reformer outlet temperature control system PI ₀ Reformer raw material pressure detector PI ₁ Hydrogen pressure detector TI ₀ Reformer raw material temperature detector TI ₁ Reformer inlet temperature detector TI ₂ Reformer outlet Temperature detector FI ₀ Reforming furnace raw material flow rate detector FI ₁ Steam flow rate detector FI ₂ Fuel flow rate detector PC ₁ Hydrogen pressure controller FC ₀ Raw material flow rate controller FC ₁ Steam flow rate controller FC ₂ Fuel flow rate controller TC ₂ Reformer outlet temperature controller XC ₁ S / C ratio controller X controller gain

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Moto Kishi 5-23-56 Kitaune, Kurashiki-shi, Okayama (72) Inventor Shuichi Yamada 2-12-1, Tsurumi-chuo, Tsurumi-ku, Yokohama-shi, Kanagawa Chiyoda Corporation In-house (72) Inventor Hiromitsu Ito 2-12-1 Tsurumi Chuo, Tsurumi-ku, Yokohama-shi, Kanagawa Chiyoda Kako Construction Co., Ltd. (72) In-house Yasumasa Morita 2-12-1 Tsurumi-chu, Tsurumi-ku, Yokohama-shi, Kanagawa Chiyoda Kakoh Construction Co., Ltd. (72) Inventor Takao Sakai 12-12 Tsurumi Chuo, Tsurumi-ku, Yokohama-shi, Kanagawa Chiyoda Kako Construction Co., Ltd. (72) Masaki Onozaki 2-chome, Tsurumi-ku, Tsurumi-ku, Yokohama-shi, Kanagawa No. 12 No. 1 Chiyoda Kako Construction Co., Ltd.

Claims (4)

[Claims] 1. In a hydrogen production apparatus for producing hydrogen by steam reforming raw material hydrocarbons, (1) the hydrogen purity to be produced is set in advance, and the hydrogen production amount is adjusted according to the required hydrogen amount of the given purity. And (2) control the flow rate of the raw material to the reforming furnace based on the hydrogen production rate set as described above, and (3) calculate the expected hydrogen production rate expected from the raw material flow rate controlled in the above, (4) The steam amount to the reforming furnace is controlled so that the steam / carbon ratio matches the expected hydrogen production amount, and (5) the hydrogen purity is maintained at a predetermined set value while satisfying the expected hydrogen production amount. A method for controlling a hydrogen production apparatus, comprising controlling the reforming furnace outlet temperature as described above. 2. The raw material flow rate to the reforming furnace is controlled by adding dead time compensation to the displacement between the hydrogen flow rate from the hydrogen production apparatus and the hydrogen production rate set in (1) above. Control method for hydrogen production device. 3. A feedforward control signal of the required fuel calculated from the flow rate of the raw material to the reforming furnace controlled in (2) and the reforming furnace inlet temperature, and the reforming controlled in (5). 3. The reformer fuel flow rate is controlled by adding a feedback control signal based on a displacement between a furnace outlet temperature set value and a reformer outlet temperature, which is gain-corrected by the expected hydrogen production amount, to control the reformer fuel flow rate. Control method for hydrogen production device. 4. A hydrogen production apparatus for producing hydrogen by steam reforming a raw material hydrocarbons, comprising: (1) a raw material hydrocarbons supply section-desulfurization section-steam reforming furnace-decarbonation section-hydrogen supply section. Each device constituent part is serially connected in series by a distribution line, and a raw material temperature detector, a raw material pressure detector and a flow control valve are arranged in the distribution line of the desulfurization section-steam reforming furnace, The reforming furnace is provided with an outlet temperature detector, an inlet temperature detector, a steam line having a steam flow rate control valve from the steam supply section, and a fuel line having a fuel flow rate control valve from the fuel supply section, and A hydrogen pressure detector is provided in the hydrogen supply unit, and (2) a reforming furnace raw material flow rate control system for controlling the raw material flow rate at the steam reforming furnace inlet according to an instruction from the hydrogen pressure detector, Reformer raw material flow rate control Control system, control of the steam supply amount of the steam reforming furnace based on the steam / carbon ratio set by the expected amount of hydrogen gas production according to the instructions from the raw material temperature detector and the raw material pressure detector A hydrogen production system comprising a system and a fuel supply amount control system for controlling a fuel flow rate of a fuel supply section so as to control a reforming furnace outlet temperature set by a hydrogen gas production expected amount.