JP2006282454A - Method and apparatus for producing synthesis gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for producing synthesis gas in which raw material gas and oxygen exist together and by which abnormal combustion in an anterior chamber portion with the potentiality of self-ignition is suppressed, the starting point of a catalyzed reaction can be made stable, and it is made possible to maintain a stable reaction over a prolonged period of time. <P>SOLUTION: The raw material gas which initiates a combustion reaction under coexistence of oxygen is introduced under coexistence of oxygen from an anterior chamber 9 into a catalyzed reaction chamber 5, where it is brought into contact with a catalyst c1 to initiate at least an oxidation reaction, whereby the synthesis gas is obtained from the raw material gas. At this time, residence inhibition gas p which inhibits residence of the raw material gas in the anterior chamber 9 is blown into the anterior chamber 9, whereby the raw material gas being under coexistence of oxygen is introduced into the catalyzed reaction chamber 5 and the synthesis gas is obtained. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention introduces a raw material gas that undergoes a combustion reaction in the coexistence state with oxygen, such as found in autothermal reforming, from the front chamber to the catalytic reaction chamber in the coexistence state with oxygen, and in this catalytic reaction chamber, The present invention relates to a synthesis gas production technique in which a synthesis gas is obtained from a raw material gas by causing at least an oxidation reaction to be brought into contact therewith.

For example, as a raw gas for FT (Fischer Tropsch) synthesis, methanol synthesis, or ammonia synthesis, it has been proposed to obtain a hydrogen-rich gas by reforming a hydrocarbon fuel using a catalytic reaction.
As a catalytic reforming reaction of this type of hydrocarbon fuel, a partial oxidation reaction and a steam reforming reaction are known.
The partial oxidation reaction is in accordance with the chemical formula shown in the following chemical formula 1, and is a so-called exothermic reaction.

  The steam reforming reaction is a so-called endothermic reaction according to the chemical formula shown in Chemical Formula 2 below.

  In a certain reforming catalyst (for example, ruthenium catalyst), both the steam reforming reaction and the partial oxidation reaction occur. Further, as the reforming catalyst housed in the catalytic reaction chamber, it is conceivable to arrange a catalyst suitable for partial oxidation on the front side and a catalyst suitable for steam reforming on the rear side.

Therefore, an oxygen-containing gas (for example, pure oxygen) is mixed with the raw material gas in which water vapor and hydrocarbon-based fuel are mixed. In the obtained mixed gas, a partial oxidation reaction is performed before the catalyst layer. The hydrogen-rich gas is generated by raising the temperature of the reaction gas to the temperature required for the steam reforming reaction and causing both reactions (steam reforming reaction and partial oxidation reaction) on the rear side of the catalyst layer. It has been proposed to get
This reforming technique is also called autothermal reforming, and in the series of reactions, the reactions shown in Chemical Formula 1 and Chemical Formula 2 occur simultaneously.

  In this reforming mode, when the catalytic reaction chamber filled with the reforming catalyst is a single reaction chamber, as shown by the solid line in FIG. 4, the temperature starts from the vicinity of the inlet of the catalytic reaction chamber 5 and moves downstream. As it goes, the temperature rises and reaches the peak temperature. After that, it converges to an equilibrium temperature determined by the inlet temperature, the inlet gas composition, and the reaction pressure.

  In the autothermal reaction, it is possible to obtain a steady and stable reaction zone where the heat balance in both reactions is balanced at a relatively high temperature side of the catalytic reaction chamber. The reaction is mainly generated, and the temperature of the raw material gas coexisting with relatively low temperature oxygen is raised to a temperature lower than the lower limit temperature at which steam reforming occurs.

  However, although the inlet portion of the catalytic reaction chamber is relatively cooler than the downstream side, it is a temperature range in which the raw material gas may cause self-ignition in the coexistence state with oxygen.

A technique disclosed in Patent Document 1 is known as an autothermal technique.
Patent Document 1 shows an example in which a pre-catalyst reaction chamber for performing a partial oxidation reaction is provided on the upstream side of the catalyst zone for performing a steam reforming reaction, as shown in FIG. 2 of the specification. .

JP 2000-84410 A (FIGS. 1 and 2)

However, this technique has the following problems.
In this configuration, the partial oxidation reaction is performed in the previous stage non-catalytic reaction chamber, but since the catalytic reaction is not used, it is difficult to reliably obtain partial oxidation and the controllability is not good.
Therefore, it is preferable that partial oxidation occurs for the first time in the catalytic reaction chamber.

As described above, the catalytic reaction is preferably caused at the site where the reaction catalyst is disposed. However, as can be seen from the previous example, a non-catalytic front chamber is provided on the upstream side. Then, the raw material gas coexisting with oxygen is guided to the catalytic reaction chamber through this front chamber, and a reaction including an oxidation reaction is performed. Therefore, in this embodiment, depending on the temperature in the vicinity of the inlet of the catalytic reaction chamber, the raw material gas may self-ignite.
More specifically, in the main flow, the advection time from the front chamber inlet to the catalyst reaction chamber inlet is relatively short, but it is not near the wall of the front chamber or the stagnation part of the flow. There is a risk that the raw material gas coexisting with oxygen stays in the site for a long time and leads to self-ignition. When self-ignition occurs, abnormal combustion occurs in the front chamber. This situation is likely to occur not only during normal operation but also when starting / starting / stopping when the conditions become severe, when the flow rate drops, when there is an abnormality / trouble, etc., but no disclosure of technology that actively avoids this situation can be found. .

  The present invention has been made in view of the above circumstances, the raw material gas and oxygen coexist, reduce the occurrence of abnormal combustion in the anterior chamber portion where there is a possibility of self-ignition, the starting point of the catalytic reaction It is possible to obtain a synthesis gas production technique capable of maintaining a stable reaction over a long period of time.

To achieve the above purpose,
A raw material gas that undergoes a combustion reaction in the coexistence state with oxygen is led from the front chamber to the catalytic reaction chamber in a coexistence state with oxygen, and is brought into contact with the catalyst in the catalytic reaction chamber to cause at least an oxidation reaction. The characteristic configuration of the synthesis gas production method for obtaining synthesis gas is:
A stagnation suppressing gas for suppressing stagnation of the raw material gas in the front chamber is blown into the front chamber, and the raw material gas coexisting with oxygen is introduced into the catalytic reaction chamber to obtain the synthesis gas.

Using this method, a raw material gas that causes a combustion reaction in the coexistence state with oxygen is guided from the front chamber to the catalytic reaction chamber in the coexistence state with oxygen, and is brought into contact with the catalyst in the catalytic reaction chamber to cause at least an oxidation reaction. And the characteristic configuration of the synthesis gas production apparatus for obtaining synthesis gas from the raw material gas is:
The front chamber is provided with a retention suppression gas blowing means for blowing a retention suppression gas that suppresses the retention of the raw material gas in the front chamber, and in the state of blowing the retention suppression gas in which the retention suppression gas blowing means is operated, oxygen The raw material gas in a coexisting state with the catalyst can be led to the catalytic reaction chamber to obtain the synthesis gas.

In this synthesis gas production method, a raw material gas coexisting with oxygen is flowed from the front chamber toward the catalytic reaction chamber. Here, a staying suppression gas that suppresses the stay of the raw material gas is blown into this flow. As this type of retention-inhibiting gas, an inert gas, a raw material gas itself, or a component gas thereof can be used. By blowing such a gas, the retention of the raw material gas in the front chamber can be prevented. It is possible to prevent the raw material gas from self-igniting due to prolonged retention in the front chamber. As a result, the occurrence of abnormal combustion can be suppressed, and not only in normal operating conditions, but also at start-up / start-stop, when the flow rate decreases, abnormal (except abnormal combustion due to self-ignition), troubles, etc. The possibility of problems occurring on the room side can be reduced.
As a synthesis gas production apparatus, a stable synthesis gas can be produced using the above-mentioned method by providing the apparatus with a retention suppression gas blowing means.

As a cause of occurrence of abnormal combustion, the gas staying in the vicinity of the flow path wall from the front chamber to the catalytic reaction chamber, or the stagnation part formed in the front chamber becomes a factor of increasing the gas residence time.
In the following, specific measures regarding these points will be described.
1 Treatment related to retention in the vicinity of the front chamber flow path wall In this case, the retention suppression gas is blown into the flow path wall side with respect to the flow of the source gas in the state of coexistence with the oxygen in the front chamber. The residence suppression gas can be flowed to suppress the occurrence of the combustion reaction.

In this method, since the retention suppressing gas is blown to the flow path wall side, the raw material gas coexisting with oxygen stays in the vicinity of the flow path wall, and the retention time becomes longer, and this gas is self-ignited. It is possible to avoid the occurrence of abnormal combustion in the front chamber by causing the above.
As an apparatus for producing synthesis gas using this method, the retention suppression gas blowing means is configured to suppress the retention on the channel wall side with respect to the flow of the source gas in the coexistence state with the oxygen in the front chamber. Gas will flow.

2. Treatment for the stagnation part of the front chamber In this case, the retention suppression gas is blown into the stagnation part of the flow of the raw material gas in the coexistence state with the oxygen in the front chamber, and the combustion is performed. Suppresses the occurrence of reaction.
Even in the stagnation part, the source gas coexisting with oxygen stays in this part for a long time, and due to the residence time, there is a possibility that self-ignition and abnormal combustion may occur. By flowing the residence-suppressing gas, residence can be suppressed and the above problem can be reduced.
As an apparatus for producing synthesis gas using this method, the retention suppression gas blowing means flows the retention suppression gas into the stagnation part of the flow of the source gas in the coexistence state with the oxygen in the front chamber. Just keep it.

Further, in the syngas production apparatus, in the front chamber, a combustion reaction induction suppression process is performed on the flow path wall surface of the flow of the source gas in a coexistence state with oxygen or the wall surface with respect to the stagnation portion. preferable.
As this type of treatment, by treating the surface in contact with the gas by gold coating or the like, the induction of the combustion reaction due to the interaction with the surface can be suppressed, and the combustion reaction can be suppressed.

  The above is a measure against the case where the gas may remain at a substantially constant site, but the following measures should be taken for the flow of the raw material gas coexisting with oxygen from the viewpoint of avoiding autoignition and abnormal combustion. Is good.

Stabilization of the mainstream flow of the raw material gas coexisting with oxygen As a countermeasure against this mainstream side, the flow time of the raw material gas coexisting with oxygen reaches the catalyst reaction chamber inlet from the front chamber inlet. The temperature of the anterior chamber is set to a temperature lower than the self-ignition temperature at which self-ignition occurs and a temperature equal to or higher than the lower limit temperature at which the oxidation reaction occurs.
Here, as the advection time, a representative flow velocity (for example, average flow velocity,...) Is selected. Then, the time required to reach the catalyst reaction chamber inlet from the front chamber inlet at the representative flow rate is determined, and the front chamber is maintained at a temperature equal to or lower than the lower limit temperature so that the gas in the front chamber does not self-ignite at that time. Therefore, the probability of occurrence of abnormal combustion on the mainstream side decreases. On the other hand, the temperature of the front chamber is set to a temperature higher than that causing an oxidation reaction in relation to the catalyst.
By doing in this way, it becomes possible to cause an oxidation reaction with the inflow to the catalytic reaction chamber while avoiding abnormal combustion accompanied by self-ignition in the front chamber.

Syngas production equipment using this method is
A temperature that is lower than the self-ignition temperature at which the flow of the raw material gas coexisting with oxygen auto-ignites in the advection time from the front chamber inlet to the catalyst reaction chamber inlet and is equal to or higher than the lower limit temperature at which the oxidation reaction occurs. Further, the apparatus can be realized by including a front chamber temperature maintaining means for setting the temperature of the front chamber.

  Now, it is preferable to set the pressure in the front chamber higher than the normal pressure. By doing so, it is possible to avoid the front chamber from being affected by the inflow of air from the outside.

As an application example of the method of the present application, the raw material gas is a gas in which steam and hydrocarbon fuel are mixed, and in the catalytic reaction chamber, a partial oxidation reaction and a steam reforming reaction are performed, and the synthesis gas is used. The hydrogen-containing gas can be obtained.
In this case, in the synthesis gas production apparatus, the raw material gas is a gas in which steam and hydrocarbon fuel are mixed, and in the catalytic reaction chamber, a partial oxidation reaction and a steam reforming reaction are performed to obtain the synthesis gas. The hydrogen-containing gas is obtained.

  Although a hydrogen-containing gas can be obtained by causing a partial oxidation reaction and a steam reforming reaction, the reaction in the catalytic reaction chamber in this reaction mode greatly depends on the temperature at the inlet of the catalytic reaction chamber. When abnormal combustion occurs in the front chamber with self-ignition, the gas state in the front chamber becomes unstable, the temperature of the catalyst reaction chamber inlet rises too much, and the maximum temperature of the catalyst reaction chamber reaches It can exceed the pyrolysis temperature and cause carbon generation, which is a problem for catalytic reactions.

  However, as described so far, by making the gas state in the front chamber stable without causing self-ignition or the like, the hydrogen-containing gas can be obtained continuously and stably.

Now, the synthesis gas production equipment
The raw material gas coexisting with the oxygen can be transferred in a straight main flow across the front chamber and the catalytic reaction chamber,
Regarding the cross section orthogonal to the main flow, it is preferable that the cross-sectional area of the cross section of the front chamber is smaller than the cross-sectional area of the cross section of the catalytic reaction chamber.

  In the case of this configuration, a smooth advection of gas can be caused by arranging the relationship between the front chamber and the catalytic reaction chamber in a linear positional relationship. And about a catalyst reaction chamber, the catalyst amount sufficient for the production amount of synthesis gas is ensured, and the flow-path cross-sectional area of the site | part is set. In this state, the gas flow rate in the catalytic reaction chamber is determined, but the gas flow rate in the front chamber increases with respect to this flow rate in relation to the cross-sectional area of the flow path. As a result, the gas passes through the front chamber at a high speed, the advection time at that part can be shortened, and this contributes to the suppression of auto-ignition in the front chamber and the stability of the reaction in the catalytic reaction chamber. Can do.

Further, when configured in this way, the front chamber and the catalytic reaction chamber are continuously formed in a single straight cylindrical reaction cylinder forming body, and the flow passage cross-sectional area of the front chamber has the front chamber It is preferable that it is determined by a solid flow path determining member housed in the housing.
In the syngas production apparatus having this configuration, the synthesis gas can be produced easily and inexpensively with a simple configuration in which the flow path storage member is housed in the linear cylindrical reaction cylinder forming body. A device can be obtained.

Hereinafter, a hydrogen-containing gas production apparatus 1 as an example of a synthesis gas production apparatus that uses the synthesis gas production method according to the present application will be described with reference to the drawings.
[GTL manufacturing process]
FIG. 1 shows a configuration of a GTL production process 3 provided with a hydrogen-containing gas production apparatus 1 on the upstream side of a GTL reactor 2 using a hydrogen-containing gas as one raw gas. As shown in the figure, this system 3 is configured to include a hydrogen-containing gas production apparatus 1 on the upstream side of the GTL reactor 2, and the hydrogen-containing gas production apparatus 1 includes a hydrocarbon system such as natural gas. Fuel f, water vapor s and oxygen o which is an oxygen-containing gas are supplied, and after reforming, a hydrogen rich gas h is sent to the GTL reactor 2.
As hydrocarbon fuel, in addition to the natural gas, alcohol, ether, LPG, naphtha, gasoline, kerosene, light oil, heavy oil, asphaltene oil, oil sand oil, coal liquefied oil, shale oil, GTL, waste in the gas state Plastic oil and biofuel can be used.

  The processing system for the hydrocarbon fuel f will be described. The hydrocarbon fuel f is desulfurized to 1 ppb or less by the desulfurization device 4, and then steam s is added to form the raw material gas f1 referred to in the present application. Oxygen o is further mixed with this raw material gas f1 as shown in the figure and introduced into a single catalytic reaction chamber 5. In the catalytic reaction chamber 5, a reforming catalyst c1 capable of generating an autothermal reforming reaction with respect to the mixed gas f2 in which the hydrocarbon fuel f, the steam s, and the oxygen o are mixed is disposed. In the catalytic reaction chamber 5, a partial oxidation reaction mainly occurs at the inlet side portion, and a steam reforming reaction mainly occurs at the downstream side.

Specifically, noble metal catalysts such as rhodium, iridium, platinum, palladium, and ruthenium are preferably used as this type of reforming catalyst, and nickel-based and cobalt-based catalysts can also be applied. Moreover, only 1 type may be used for a metal and it can also use 2 or more types together as needed. These catalysts may have any shape, and there is no particular limitation on the carrier. Desirably, a carrier mainly composed of one kind selected from alumina, zirconia, silica, titania, magnesia, and calcia is preferable. Then, it is preferably used in the form of a tablet-shaped, spherical, ring-shaped molded product, or molded into a honeycomb shape.
A typical example of the production of this type of catalyst will be described in the case where ruthenium is supported on an alumina support. For example, a spherical alumina support (diameter 4 to 6 mm) is immersed in an aqueous ruthenium chloride (RuCl ₃ .3H ₂ O) solution. It can be prepared by drying in air at 80 ° C. for 2 hours, followed by immobilization (treatment with aqueous NaOH) and hydrogen reduction.

  As shown in FIG. 1, the catalytic reaction chamber 5 is arranged in a vertical vertical direction, and a raw material gas f1 (a gas obtained by mixing water vapor s with a hydrocarbon fuel f) is supplied from the upper side, and oxygen o Is introduced from an inlet 5a provided on the upper side of the catalytic reaction chamber 5, finishes the reforming reaction, and the hydrogen rich gas h is sent from the lower side of the catalytic reaction chamber 5 to the GTL reactor 2 side. It is done. Hereinafter, a specific configuration of the hydrogen-containing gas production apparatus 1 according to the present application will be described with reference to FIGS.

[Hydrogen-containing gas production equipment]
The hydrogen-containing gas production apparatus 1 is configured to take steps up to desulfurization, steam addition, oxygen mixing and reforming for the hydrocarbon fuel f described above.
The desulfurization is performed in the desulfurization chamber 6, and a raw material gas f <b> 1 in which water vapor s is mixed with the hydrocarbon fuel f delivered from the desulfurization chamber 6 is generated. FIG. 2 shows a specific configuration of the source gas chamber 7, the mixing chamber 8, the front chamber 9, and the catalytic reaction chamber 5 in this apparatus 1. Since the present application is characterized by the configuration of the front chamber 9 and its usage, only the upper side of the catalytic reaction chamber 5 is shown in FIG. The outlet provided on the lower side of the catalytic reaction chamber 5 is connected to the hydrogen inlet 2a of the GTL reactor 2 through the outlet 5b through a connecting pipe 5c. FIG. 3 is a view showing a detailed structure of the front chamber 9 and a flow state of the portion.

Desulfurization The desulfurization chamber 6 is provided with a desulfurization catalyst c2 such as a copper-zinc high-order desulfurization catalyst mixed with copper oxide, zinc oxide or the like. In this chamber 6, the sulfur compound concentration is set to 1 ppb or less.
In addition to the above-described copper zinc-based high-order desulfurization catalyst, silver-based catalysts, and desulfurization catalysts containing nickel, chromium, manganese, iron, cobalt, palladium, iridium, platinum, ruthenium, rhodium, gold, etc. can also be employed. .

The hydrocarbon-based fuel f that has undergone steam mixing and desulfurization is added with steam s that is separately supplied through the steam supply pipe 10. Here, the amount of water vapor s with respect to the hydrocarbon-based fuel f is 0.1 to 3.0 (preferably with the ratio of water vapor H ₂ O to carbon C contained in the fuel as a molar ratio [H ₂ O / C]. 0.1 to 1.0). Moreover, the temperature in this part is about 200-400 degreeC (preferably 200-300 degreeC). The gas thus obtained is referred to as a raw material gas f1 in the present application.

  On the other hand, in the hydrogen-containing gas production apparatus 1 of the present application, as shown in FIGS. 1, 2, and 3, a hydrocarbon-based fuel f or water vapor s (becomes a component gas for the raw material gas f1), or a raw material gas. The purge gas p, which is f1 or an inert gas, is supplied, and oxygen o is also supplied as described above. These gases are appropriately reacted in the reforming unit 11 described in detail below.

Reforming unit 11
As shown in FIGS. 2 and 3, the reforming unit 11 includes a source gas chamber 7, a mixing chamber 8 and a front chamber 9 on the upper side of the unit, and a catalytic reaction chamber 5 on the lower side. I have.
The upper part of the reforming unit 11 has a substantially double pipe structure, and is configured such that the purge gas p can be supplied to the lower region of the front chamber 9 through the inner pipe 11a. Further, as shown in FIG. 2, a thermocouple t1 for temperature measurement is disposed in the inner tube 11a so as to extend to the middle part of the front chamber, and the representative temperature (inlet temperature) of the front chamber 9 is set. It is configured to be measurable.

Source gas chamber 7
As shown in FIG. 2, the source gas chamber 7 has an introduction port 7a into which the source gas f1 mixed with water vapor s is introduced, an intermediate passage portion 7b in which the introduction port 7a is opened, and a flow from the intermediate passage portion 7b. The passage section 7c is configured to have a large passage section. A mixing chamber 8 is provided on the lower side of the flow path expanding portion 7c.

Mixing chamber 8
The mixing chamber 8 employs a so-called shell-and-tube type mixing structure. From the oxygen chamber 8b provided outside the channel 8a into which the raw material gas f1 flows from the channel expanding portion 7c. , Oxygen o flows in. Accordingly, when oxygen o flows into the raw material gas f1, the mixed gas f2 in which the raw material gas f1 and the oxygen o are mixed (in a coexisting state) can be formed in the tube 8a.
As shown in the figure, the tube 8a is extended on the lower side beyond the separation distance between the partition plates 8c and 8c that divide the mixing chamber 8. By flowing down this flow path, sufficient mixing can be achieved. It is configured to obtain a state.
Here, the amount of oxygen o relative to the hydrocarbon-based fuel f is 0.05 to 1.0 (preferably 0), where the ratio of oxygen O ₂ to carbon C contained in the fuel is [O ₂ / C] in molar ratio. .3 to 0.7). Moreover, the temperature in this part is about 200-400 degreeC (preferably 200-300 degreeC). The gas thus obtained is referred to as a mixed gas f2 in the present application.

Front room 9
The front chamber 9 is provided so as to serve as an adjustment chamber for the catalyst reaction chamber 5, and the introduction portion 9 a from which the tube 8 a described above is extended, and the introduction portion 9 a and the catalyst reaction chamber 5 And an adjusting portion 9b provided therebetween.
As shown in the drawing, tubes 8a penetrate and extend downward from the introduction portion 9a, and the mixed gas f2 is discharged from the tips of these tubes 8a. The outer peripheral portion 9c of the tube 8a is solid, and gas does not stay. Further, the structure in which the purge gas p described above is supplied to the tip of the introduction portion 9a through the inner pipe 11a is adopted, and the mixed gas f2 is provided by the supply of the purge gas p and the solid structure outside the tube 8a. Ascending to the upper side and stagnation do not occur.
Here, as will be understood from FIGS. 2 and 3, the purge gas p is jetted to the peripheral portion on the lower end side of the tube 8a, and flows on the wall surface side of the flow path with respect to the mixed gas f2. Further, as will be described later, the gas flow path 9d of the adjusting portion 9b is provided with a heat insulating material 9h having air permeability, which forms a stagnation portion at its tip portion and its peripheral portion. By flowing the purge gas p as a flow different from the flow of f2, the probability of gas stagnation at the wall surface 9dw and the stagnation portion 9ds can be reduced. In the present application, a configuration in which a retention suppression gas that suppresses the retention of the raw material gas in the front chamber 9 is referred to as a retention suppression gas blowing means.

  The adjusting portion 9b appropriately adjusts the temperature of the front chamber 9 at this portion, and further mixes the mixed gas f2 flowing in the tube 8a, which is a relatively thin flow path, while slightly expanding the flow path. Introducing into the catalytic reaction chamber 5 is performed smoothly. Therefore, as shown in FIGS. 2 and 3, in the gas flow path 9d through which the mixed gas f2 flows in the adjusting portion 9b, the cross-sectional area is slightly increased and the gas flow velocity is decreased.

As shown in the figure, an alumina block 9e and a porous block 9f made of silicon nitride are provided on the upper side and the lower side of the adjustment unit 9b, respectively, in a state where the gas flow path 9d of the adjustment unit 9b is formed. ing. The reason for providing these materials is to prevent heat from the catalytic reaction chamber 5 from propagating to the upstream side and to perform heat insulation well. In the figure, a ceramic rope 9g is installed on the outer diameter side portion of the block 9f so that gas does not flow between the block 9f and the refractory material.
Further, in the example shown in FIG. 2, a heat insulating material 9 h having air permeability is disposed in the gas flow path 9 d of the adjusting portion 9 b, and the heat insulating and mixed unreacted gas at the boundary between the catalytic reaction chamber 5 and the front chamber 9 is disposed. Convection prevention is ensured.

As described above and as can be seen from FIGS. 2 and 3, in the configuration of the present application, the raw material gas coexisting with oxygen flows in a straight main stream across the front chamber 9 and the catalytic reaction chamber 5. The cross-sectional area of the cross section of the front chamber 9 is the cross-sectional area of the cross section of the catalytic reaction chamber 5 with respect to the cross section (transverse section in FIG. 2) perpendicular to the main flow. Set smaller. As a result, the flow expands at the stage of entering the catalytic reaction chamber 5, and the flow velocity rapidly decreases.
Further, as is clear from these figures, the front chamber 9 and the catalytic reaction chamber 5 are continuously formed in a single straight cylindrical reaction cylinder forming body, and the flow passage cross-sectional area of the front chamber 9 is It is determined by solid flow path determining members (alumina block 9e and block 9f described above) housed in the front chamber 9.

Catalytic reaction chamber 5
The catalytic reaction chamber 5 is a main part of the hydrogen-containing gas production apparatus 1 according to the present application, and is a part where the reforming catalyst c1 is disposed as described above.
Further, the gas space velocity per a total gas flow rate supplied to the catalytic reaction chamber 5 times (however, the standard values of the state conversion) ^{750h -1} ~300000h -1 (preferably ^{10000h -1 ~300000h} -1 in, more preferably 50,000 h ^{−1 to} 300,000 h ⁻¹ ).

  There is no particular limitation on the pressure during the reaction. The reaction pressure can be changed depending on the application. As shown in the examples, when used for synthesizing liquid fuel such as GTL, it is used at 2 to 7 MPa. On the other hand, when it is used as the raw gas of the fuel cell, it is used near normal pressure (for example, 1 MPa or less).

The above is the configuration of the hardware side of the hydrogen-containing gas production apparatus 1 according to the present application. However, in this apparatus configuration, the reaction state in the front chamber 9 and the catalytic reaction chamber 5 is appropriate for the apparatus of the present application. It is configured to
That is, the device 1 of the present application is devised to optimize the inlet temperature of the mixed gas f2 to the catalytic reaction chamber 5. For example, in the configuration described so far, the gas flow path 9d of the mixed gas f2 is made relatively small, and the flow rate in the flow path 9d is increased, whereby the residence time of the mixed gas f2 in the front chamber 9 is set to a fixed time. It is as follows. Further, the heat insulation at the boundary between the catalytic reaction chamber 5 and the front chamber 9 is made high so that the temperature of the catalytic reaction chamber 5 does not affect the front chamber 9. Furthermore, the purge gas p is introduced into the front chamber 9 to prevent the mixed gas f2 from backflowing and staying, and the like, which is a contrivance on the hardware side in the present application.

In the hydrogen-containing gas production apparatus 1 of the present application, as shown in FIG. 1, a control device 13 for controlling the reaction state is provided, and the type of hydrocarbon-based fuel f and input into the system are provided. The control device 13 can monitor the amount and temperature, the amount and temperature of steam s input into the system, and the amount and temperature of oxygen o into the system.
On the other hand, as shown in FIG. 2, the inlets and outlets (catalysts) of the adjusting portion 9b of the front chamber 9 are formed by the thermocouples t1 and t2 inserted into the unit 11 from the upper and lower sides of the reforming unit 11 described above. The temperature at the inlet 5a) of the reaction chamber and the temperature in the flow direction in the catalyst reaction chamber 5 can also be monitored.
And according to the control command from the control apparatus 13, the hydrocarbon fuel injection amount, the water vapor input amount, and the oxygen input amount into the hydrogen-containing gas production device 1 can be adjusted.

Now, the configuration of the control device 13 will be described. As shown in FIGS. 1 and 4, the control device 13 includes a lower limit temperature at which the reforming catalyst c1 causes a partial oxidation reaction as a partial oxidation lower limit temperature T1, a steam reforming reaction. The lower limit temperature that causes the steam reforming lower limit temperature T2 is the advection required for the mixed gas f2 to reach the catalytic reaction chamber 5 from the mixing chamber 8 at a temperature not lower than the partial oxidation lower limit temperature T1 and lower than the steam reforming lower limit temperature T2. A temperature setting means 13a for setting the temperatures of the mixing chamber 8 and the front chamber 9 to a temperature lower than the self-ignition temperature with respect to the self-ignition temperature T3, which is a temperature at which the mixed gas f2 self-ignites with time, is provided. .
Further, with respect to this temperature setting means 13a, the higher temperature with respect to the partial oxidation lower limit temperature and the dew point temperature T4 of the mixed gas f2 is set as the front chamber lower limit temperature, and the self-ignition temperature of the mixed gas f2 is set as the front chamber upper limit temperature. There is provided a front chamber mixed gas temperature maintaining means (simply referred to as temperature maintaining means in FIG. 1) 13b for maintaining the temperature of the mixed gas f2 flowing through the front chamber 9 at a temperature lower than the upper limit temperature of the front chamber and higher than the lower limit temperature of the front chamber. ing.
Here, the dew point temperature of the mixed gas referred to in the present application is a temperature at which the partial pressure of water vapor at that portion becomes a saturated water vapor pressure, and is a temperature at which dew condensation occurs when only the temperature decreases in that environment.

Hereinafter, the lower limit temperature and the upper limit temperature in the control device 13 will be described.
Lower limit temperature The partial oxidation lower limit temperature is the lower limit temperature T1 at which the mixed gas f2 comes into contact with the reforming catalyst c1 to cause a partial oxidation reaction. The lower limit temperature T1 is determined by the reforming catalyst c1 accommodated in the catalyst reaction chamber 5. . For example, when the reforming catalyst c1 is a ruthenium-based catalyst as described above, the temperature is about 200 ° C., and when the reforming catalyst c1 is a rhodium-based catalyst, the temperature is about 300 ° C. Therefore, the partial oxidation lower limit temperature is stored and stored in the storage unit 13c provided in the control device 13, and the partial oxidation lower limit temperature T1 can be appropriately read and used on the control device 13 side.

  On the other hand, for the mixed gas f2, the dew point T4 of the mixed gas is determined according to the mixing ratio of the hydrocarbon fuel f, the water vapor s, and the oxygen o. Therefore, dew point temperature data according to the mixing ratio of each gas is stored in the storage means 13c, and by using this data, the dew point temperature T4 of the mixed gas f2 present in the front chamber 9 at present is calculated. It can be estimated from the amount of each gas input.

  Therefore, in the control device 13, the dew point temperature of the mixed gas f2 estimated from the partial oxidation lower limit temperature T1 based on the type of the reforming catalyst c1 and the input amount / temperature of the mixed gas f2 estimated to exist in the front chamber. According to T4, a lower limit temperature (anterior chamber lower limit temperature) is obtained as the temperature on the higher side of both.

The upper limit temperature steam reforming lower limit temperature is the lower limit temperature T2 at which the mixed gas f2 comes into contact with the reforming catalyst c1 to cause the steam reforming reaction, and the steam reforming is performed by the reforming catalyst c1 stored in the catalyst reaction chamber 5. The lower limit temperature T2 is determined. For example, when the reforming catalyst c1 is a ruthenium-based catalyst as described above, the temperature is about 400 ° C., and when the reforming catalyst c1 is a nickel-based catalyst, the temperature is about 400 ° C. Therefore, the steam reforming lower limit temperature T2 is stored and stored in the storage means 13c provided in the control device 13, and the steam reforming lower limit temperature T2 can be appropriately read and used on the control device 13 side. Yes.

The autoignition temperature T3 of the mixed gas f2 present in the front chamber 9 is also taken into consideration for the steam reforming lower limit temperature T2. That is, the self-ignition temperature T3 is determined by the composition of the mixed gas f2 in the front chamber 9 and the residence time in the front chamber 9 (this residence time refers to the mixing chamber 8 after the oxygen o is mixed in the mixing chamber 8). It is the time from the exit to the inlet 5a of the catalyst reaction chamber 5, and in the present case, the advancing time of the mixed gas f2 through the tube 8a on the outlet side of the mixing chamber 8 to the inlet 5a of the catalyst reaction chamber 5 Means).
Therefore, the self-ignition temperature T3 according to the composition state of the mixed gas f2 that is ignited for the first time during the residence time is stored in the storage means 13c. The upper limit temperature is related to this temperature and the steam reforming lower limit temperature T2. Get. FIG. 5 shows the relationship between the residence time (indicated as “ignition delay time” in the figure) and the self-ignition temperature T3 (indicated as “mixed gas temperature” in the figure) with respect to the mixed gas f2. The figure shows that the mixed gas f2 is a hydrocarbon-based fuel natural gas, and [N ₂ / C]
, [O ₂ / C] are (0.6 to 1.0) and (0.1 or 0.4), respectively. The pressure of the mixed gas in this state is 4 MPa. The combustion reaction is limited by the collision frequency of the mixed gas, and the actual frequency factor depends on the diameter and degree of freedom of the molecule, but if the collision frequency of H ₂ O is 1, N ₂ is equivalent to about 0.7 to 0.8. Therefore, in the embodiment of the figure, N ₂ is introduced instead of water vapor.

  In the control device 13, the temperature setting means 13a, more specifically, the front chamber mixed gas temperature maintaining means 13b, according to the above-described method, introduces the hydrocarbon-based fuel input, the steam input, and the oxygen input. Adjust the amount etc. to ensure a good driving condition.

Now, maintaining the temperature of the front chamber mixed gas f2 between the upper limit temperature and the lower limit temperature of the front chamber means that the temperature of the mixed gas at the inlet 5a of the catalytic reaction chamber 5 is adjusted appropriately. To do. This temperature leads to appropriate control of the reaction temperature in the catalytic reaction chamber 5.
Therefore, the temperature setting means 13a and the front chamber mixed gas temperature maintaining means 13b satisfy the requirements related to the front chamber upper limit temperature and the lower limit temperature, and the mixed gas f2 in the front chamber 9 according to the representative temperature of the catalytic reaction chamber 5. The structure which adjusts the temperature of is adopted. For example, with the deterioration of the catalyst c1 accommodated in the catalytic reaction chamber 5, the partial oxidation reaction is delayed, and the temperature of the catalytic reaction chamber 5 is delayed to cause the steam reforming reaction (resulting in the catalytic reaction). The peak temperature position in the chamber 5 moves downstream or the peak temperature rises). Therefore, the temperature of the front chamber can be adjusted.
This type of temperature adjustment can be performed by adjusting the amount of water vapor or oxygen with respect to the hydrocarbon fuel.

Hereinafter, the operation state of the hydrogen-containing gas production device 1 according to the present application by the control device 13 will be described.
Control in the situation where the mixed gas temperature in the front chamber 9 is within the front chamber upper limit temperature (auto-ignition temperature) and the front chamber lower limit temperature (the lower of the partial oxidation lower limit and the dew point temperature). The reaction in 5 is presumed to be in an appropriate state. However, in order to keep the state of the catalytic reaction chamber 5 stable even in such an appropriate state, the temperature of the mixed gas f2 in the front chamber 9 is set to the front chamber upper limit temperature and the front chamber lower limit temperature. In this range, the temperature is controlled according to the representative temperature (for example, peak temperature) of the catalytic reaction chamber 5. By doing so, a stable and proper operating state can be maintained.

[Another embodiment]
Another embodiment of the present application will be described.
(1) In the above embodiment, an example of the autothermal reforming reaction has been shown. However, the technical idea according to the present application may cause combustion when long-term residence occurs in a coexistence state with oxygen. Adaptable to certain reactions. This type of reaction includes many gas phase oxidation reactions such as ethylene oxo reaction.
(2) In the above-described embodiment, a gas flow path having substantially the same diameter as the tube extending from the mixing chamber is provided in the adjustment section of the front chamber, and the flow rate of the mixed gas is controlled via the tube and the gas flow path. Although an example has been shown in which the residence time is shortened by maintaining it relatively high and the mixed gas is guided to the catalytic reaction chamber, as shown in FIG. 6, a combined channel 90 is provided downstream from the outlet of the tube 8a. The mixed gas f <b> 2 may be caused to flow into the catalytic reaction chamber 5 through 90. However, the cross-sectional area of the combined flow path 90 is set so that the flow velocity realized at this portion is higher than the minimum flow velocity of the source gas chamber 7. In this way, the properties of the mixed gas f2 can be made uniform, and the diffusion of the mixed gas f2 in the cross section direction of the catalytic reaction chamber in the vicinity of the inlet of the catalytic reaction chamber 5 can be improved.
(3) In the above embodiment, the hydrogen-containing gas production apparatus is provided with the temperature setting means 13a and the front-chamber mixed gas temperature maintaining means 13b to positively input water vapor and oxygen to the hydrocarbon fuel. The amount was controlled and the reaction in the catalytic reaction section was maintained in an appropriate state. However, when the normal operation state was almost fixed, the reforming unit 11 described above in each chamber 7, 8, 9 Since the flow velocity is substantially determined, the flow path cross-sectional configuration may be configured so that the temperature of the mixed gas in the front chamber 9 is appropriate.
That is, when the partial oxidation lower limit temperature is determined by the reforming catalyst c1 and the gas composition of the mixed gas f2 is determined, the dew point temperature is determined, and thus the anterior chamber lower limit temperature referred to in the present application is determined.
On the other hand, with respect to the front chamber upper limit temperature, the steam reforming lower limit temperature is determined by the reforming catalyst c1, and the mixed gas depends on the shape of the gas flow path 9d in the tube 8a through which the mixed gas f2 flows and the adjusting section 9b on the downstream side. The maximum residence time until f2 reaches the catalytic reaction chamber 5 from the mixing chamber 8 is determined. Therefore, the relationship between the temperature and the residence time of the mixed gas shown in FIG. 5 as described above is obtained in advance, and even when the mixed gas f2 stays in the front chamber for the maximum residence time, the mixed gas is used. The temperature at which f2 does not self-ignite can be the front chamber upper limit temperature.
(4) In the above embodiment, the example of controlling the temperature of the mixed gas in the front chamber according to the representative temperature of the catalytic reaction chamber has been shown. Basically, partial oxidation is performed at the inlet of the catalytic reaction portion. Since it is sufficient that the reaction can be generated, the temperature of the mixed gas in the front chamber is guided to the lower limit temperature side of the front chamber in order to configure the control of the temperature setting unit 13a and the temperature maintaining unit 13b of the front chamber mixed gas described above. It can also be configured.
In this case, the reaction can be controlled in such a direction as to avoid the generation of carbon that is likely to be a problem in the catalytic reaction portion while ensuring the occurrence of the partial oxidation reaction necessary for the reforming.
(5) In the above embodiment, when the mixed gas stays in the front chamber and the mixed gas stays in the front chamber for the residence time, the mixed gas is heated to a temperature at which self-ignition does not occur. Although an example of performing reforming by setting a chamber has been shown, a means for actively preventing flame propagation may be provided in the front chamber. FIG. 7 shows such an example. A frame arrester 60 is disposed at the tip of the tube 8a, and the inner wall 61 of the gas flow path 9d and the stagnation portion 62 are coated with gold for preventing a combustion reaction. A covering process w is performed. Even in this way, flame formation and propagation in the front chamber 9 can be prevented. This process is called a combustion reaction induction suppression process.
(6) In the embodiment described so far, the autothermal reaction is an example in which steam is added to a hydrocarbon-based fuel, and after undergoing a partial oxidation reaction, a steam reforming reaction is caused. Although shown, a so-called carbon dioxide reforming reaction may be caused. This carbon dioxide reforming reaction is also an endothermic reaction, and the reaction form follows the chemical formula 3 shown below.

FIG. 8 shows a configuration example of a GTL manufacturing process for performing steam reforming according to Chemical Formula 2 and carbon dioxide reforming according to Chemical Formula 3 in correspondence with FIG. Although the equipment configuration is the same as that shown in FIG. 1, in the example shown in FIG. 1, only the steam s is added to the hydrocarbon fuel f to obtain the raw material gas f1, whereas in this example, Water vapor s and carbon dioxide CO ₂ are also added to obtain a raw material gas f1. In this GTL manufacturing process, both the steam reforming reaction and the carbon dioxide reforming reaction can proceed.
Even in such a reaction mode, in the method and apparatus for producing a hydrogen-containing gas according to the present application, the state in the front chamber and the subsequent catalytic reaction chamber can be made as desired.

The figure which shows the structure of the GTL manufacturing process provided with the manufacturing apparatus of the hydrogen containing gas which concerns on this invention. Diagram showing the upper structure of the reforming unit Diagram showing details of the front chamber of the reforming unit Diagram showing the relationship between the inlet temperature in the catalytic reaction chamber and the temperature in the catalytic reaction chamber Diagram showing the relationship between the mixed gas temperature and the ignition delay time Diagram showing another configuration example of the front chamber The figure which shows the example which performed the flame propagation suppression process in the front chamber structure corresponding to FIG. The figure which shows the structural example corresponding to FIG. 1 which shows the example which performs both steam reforming and carbon dioxide reforming

Explanation of symbols

1 Hydrogen-containing gas production equipment (synthesis gas production equipment)
2 GTL reactor 5 Catalytic reaction chamber 7 Raw material gas chamber 8 Mixing chamber 8a Tube 8b Oxygen chamber 9 Front chamber 11 Reforming unit 13 Controller 13a Temperature setting means 13b Temperature maintaining means 13c Storage means c1 Reforming catalyst c2 Desulfurization catalyst f Carbonization Hydrogen fuel f1 Raw gas f2 Mixed gas h Hydrogen rich gas o Oxygen p Purge gas s Water vapor

Claims (17)

A raw material gas that undergoes a combustion reaction in the coexistence state with oxygen is led from the front chamber to the catalytic reaction chamber in a coexistence state with oxygen, and is brought into contact with the catalyst in the catalytic reaction chamber to cause at least an oxidation reaction. A method for producing synthesis gas to obtain synthesis gas,
A method for producing a synthesis gas, wherein a residence suppression gas for suppressing residence of a source gas in the front chamber is blown into the front chamber, and the source gas in a coexistence state with oxygen is introduced into the catalytic reaction chamber to obtain the synthesis gas.   2. The synthesis gas production according to claim 1, wherein, with respect to the flow of the raw material gas in the coexistence state with the oxygen in the front chamber, the residence suppression gas is caused to flow toward the flow path wall side to suppress the occurrence of the combustion reaction. Method.   The method for producing a synthesis gas according to claim 1 or 2, wherein the stagnation suppressing gas is caused to flow through a stagnation part of the flow of the raw material gas in the coexistence state with the oxygen in the front chamber to suppress the occurrence of the combustion reaction.   A temperature that is lower than the self-ignition temperature at which the flow of the raw material gas coexisting with oxygen auto-ignites in the advection time from the front chamber inlet to the catalyst reaction chamber inlet and is equal to or higher than the lower limit temperature at which the oxidation reaction occurs. The method for producing a synthesis gas according to any one of claims 1 to 3, wherein the temperature of the anterior chamber is set.   The method for producing a synthesis gas according to any one of claims 1 to 4, wherein the retention suppression gas is an inert gas, the raw material gas, or a component gas thereof.   The method for producing synthesis gas according to any one of claims 1 to 5, wherein the pressure in the front chamber is set higher than normal pressure.   The raw material gas is a gas in which steam and hydrocarbon fuel are mixed, and a partial oxidation reaction and a steam reforming reaction are performed in the catalytic reaction chamber to obtain a hydrogen-containing gas as the synthesis gas. The method for producing a synthesis gas according to any one of 6. A raw material gas that undergoes a combustion reaction in the coexistence state with oxygen is led from the front chamber to the catalytic reaction chamber in a coexistence state with oxygen, and is brought into contact with the catalyst in the catalytic reaction chamber to cause at least an oxidation reaction. A synthesis gas production apparatus for obtaining synthesis gas,
The front chamber is provided with a retention suppression gas blowing means for blowing a retention suppression gas that suppresses the retention of the raw material gas in the front chamber, and in the state of blowing the retention suppression gas in which the retention suppression gas blowing means is operated, oxygen The syngas production apparatus for obtaining the synthesis gas by introducing the source gas in a coexisting state to the catalytic reaction chamber.   The syngas production apparatus according to claim 8, wherein the staying suppression gas blowing means causes the staying suppression gas to flow toward a flow path wall with respect to the flow of the raw material gas in a coexistence state with the oxygen in the front chamber. .   The synthetic gas production apparatus according to claim 8 or 9, wherein the retention suppression gas blowing means causes the retention suppression gas to flow through a stagnation portion of the flow of the raw material gas in a coexistence state with the oxygen in the front chamber.   A temperature that is lower than the self-ignition temperature at which the flow of the raw material gas coexisting with oxygen auto-ignites in the advection time from the front chamber inlet to the catalyst reaction chamber inlet and is equal to or higher than the lower limit temperature at which the oxidation reaction occurs. The syngas production apparatus according to any one of claims 8 to 10, further comprising an anterior chamber temperature maintaining means for setting the temperature of the anterior chamber.   The combustion reaction induction suppression process is performed on the flow path wall surface or the front chamber wall surface with respect to the stagnation part of the flow of the raw material gas in the coexistence state with the oxygen. Syngas production equipment.   The synthetic gas production apparatus according to any one of claims 8 to 12, wherein the retention suppression gas is an inert gas, the raw material gas, or a component gas thereof.   The apparatus for producing synthesis gas according to any one of claims 8 to 13, wherein the pressure in the front chamber is set higher than normal pressure. The source gas in the coexistence state with the oxygen is capable of advancing by forming a linear main flow across the front chamber and the catalytic reaction chamber,
The cross-sectional area of the cross section of the said front chamber is smaller than the cross-sectional area of the cross section of the said catalytic reaction chamber regarding the cross section orthogonal to the said main flow, The synthesis gas of any one of Claims 8-14 Manufacturing equipment.   The front chamber and the catalytic reaction chamber are continuously formed in a single straight cylindrical reaction cylinder forming body, and the cross-sectional area of the cross section of the front chamber with respect to the cross-sectional area orthogonal to the main flow is the front cross section. The synthetic gas production apparatus according to claim 8, which is determined by a solid flow path determining member housed in a room.   The raw material gas is a gas in which steam and hydrocarbon fuel are mixed, and a partial oxidation reaction and a steam reforming reaction are performed in the catalytic reaction chamber to obtain a hydrogen-containing gas as the synthesis gas. The synthetic gas production apparatus according to any one of 16.

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