JP5348938B2 - Carbon monoxide gas generator and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbon monoxide gas generation apparatus that exhibits a high yield of carbon monoxide gas and can be operated with reduced maintenance. <P>SOLUTION: High yield of carbon monoxide gas and operation with reduced maintenance can be attained by providing a reactor into which a hydrocarbon gas, an oxygen-based gas and steam are introduced as raw gases and which generates carbon monoxide gas as a mixed gas rich in hydrogen gas and high in carbon monoxide gas concentration by subjecting the raw gases to a catalytic reaction on a catalyst to thereby carry out a combustion reaction and a conversion reaction of the hydrocarbon gas, and introducing steam to the downstream of the reactor. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a carbon monoxide gas generator that generates carbon monoxide gas from a hydrocarbon compound gas such as natural gas, propane gas, gasoline, naphtha, kerosene, methanol, and biogas, water, and oxygen-based gas. And methods.

  2. Description of the Related Art Conventionally, carbon monoxide gas is required as an atmosphere gas for metal surface treatment such as carburizing treatment, and as a raw material for producing polyurethane and polycarbonate.

Conventionally, such carbon monoxide gas uses a hydrocarbon gas and an oxygen gas as raw materials, is reformed using a catalyst, and is a gas mixture rich in hydrogen monoxide and having a high carbon monoxide gas concentration. Is obtained by separating carbon monoxide gas from this mixed gas by a method such as PSA (Pressure Swing Adsorption) (for example, Patent Documents 1 and 2 below) ).
Japanese Patent Application Laid-Open No. 11-137942 JP 2001-335305 A

  However, in the method in which hydrocarbon gas and oxygen gas are used as raw materials and reformed using a catalyst to generate carbon monoxide gas as a gas mixture rich in hydrogen and having a high carbon monoxide concentration, the carbon potential of the entire system If the carbon monoxide gas yield is improved by increasing the temperature, the carbon will be deposited downstream of the reactor, including a heat exchanger provided to recover the heat generated in the reactor. There is a problem that the inside is contaminated by carbon deposition. For this reason, it was necessary to operate under conditions that do not cause carbon deposition at the expense of the yield of carbon monoxide gas, or to operate while periodically performing maintenance to remove the deposited carbon.

  The present invention has been made to solve such a problem, and provides a carbon monoxide gas generation apparatus and method that enable operation with a high yield of carbon monoxide gas and reduced maintenance. For the purpose.

In order to achieve the above object, a carbon monoxide gas generator of the present invention has a hydrocarbon gas, an oxygen gas, and water vapor introduced as a raw material gas, and the raw material gas is contacted with a catalyst to react with the hydrocarbon gas. A reactor that generates carbon monoxide gas as a gas mixture rich in hydrogen gas and having a high carbon monoxide gas concentration by causing a combustion reaction and a metamorphic reaction, and a monoxide as product gas from the gas mixture generated in the reactor A separation device for separating carbon gas ,
The gist is that a fluid mainly containing H ₂ O is introduced downstream of the reactor as a fluid for suppressing carbon deposition on the metal surface inside the pipe .

In order to achieve the above object, the carbon monoxide gas generation method of the present invention is a hydrocarbon-based gas, an oxygen-based gas, and water vapor introduced as a raw material gas, and the raw material gas is brought into contact with a catalyst to react with the hydrocarbon-based gas. By generating a gas combustion reaction and a metamorphic reaction, a reaction step of generating carbon monoxide gas as a mixed gas rich in hydrogen gas and having a high carbon monoxide gas concentration, and as a product gas from the mixed gas generated in the reaction step A separation step of separating carbon monoxide gas ,
The gist is to introduce a fluid mainly containing H ₂ O as a fluid for suppressing carbon deposition on the metal surface inside the pipe downstream of the reaction step.

The carbon monoxide generator and method of the present invention have a separation device or process for separating carbon monoxide gas as a product gas from a mixed gas generated in a reactor or reaction step. Then, by introducing a fluid mainly containing H ₂ O as a fluid for suppressing carbon deposition on the metal surface inside the pipe downstream of the reactor or the reaction step, It effectively prevents carbon deposition on the metal surface. For this reason, it is possible to operate under conditions where the generation potential of carbon monoxide gas is high, and maintenance such as removal of pollutants can be greatly reduced. As described above, since the fluid containing mainly H ₂ O can be introduced downstream of the reactor or the reaction process to suppress the precipitation of carbon, the amount of water vapor introduced into the reactor or the reaction process can be suppressed. The carbon monoxide concentration of the reformed gas obtained by the reactor or the reaction process can be greatly improved, and the yield of carbon monoxide can be greatly improved.

In the present invention, a heat exchanger for recovering heat generated in the reactor is provided downstream of the reactor, and a fluid mainly containing H ₂ O is introduced between the outlet of the reactor and the inlet of the heat exchanger. In this case, the heat exchanger provided downstream of the reactor in order to recover the heat of the reactor is effectively prevented from being contaminated by carbon deposition, and the generation potential of carbon monoxide gas is high. In addition to enabling operation under conditions, maintenance such as removal of contaminants can be greatly reduced.

In the present invention, the raw material gas introduced into the reactor, so that the molar ratio of C of between H _{2 O} hydrocarbon gas of water vapor becomes 0.5 or less in H _{2 O} / C, hydrocarbons When the mixing ratio of the system gas, the oxygen-based gas, and the water vapor is set, the carbon monoxide gas concentration in the generated mixed gas becomes high. Further, since a high temperature is obtained in the reactor, the heat obtained from the mixed gas discharged from the reactor can be used for heating the raw material and the fluid mainly containing H ₂ O introduced downstream of the reactor.

In the present invention, the raw material gas introduced into the reactor, the molar ratio of O ₂ in the oxygen-based gas and C of the hydrocarbon-based gas is 0.3 to 0.5 at a O _{2 /} C Thus, when the mixing ratio of hydrocarbon gas, oxygen gas, and water vapor is set, excessive heat generation due to internal combustion reaction is prevented, and catalyst damage is prevented. The composition can be maintained properly.

In the present invention, the reactor uses a Rh-modified (Ni—CeO ₂ ) —Pt catalyst so that the combustion reaction and the shift reaction of the hydrocarbon gas are simultaneously performed in the same reaction region. In some cases, the combustion reaction, which is an exothermic reaction, and the metamorphic reaction, which is an endothermic reaction, are simultaneously performed in the same reaction region, so that the heat energy generated by the combustion reaction can be used as a heat source for the metamorphic reaction, resulting in extremely high energy efficiency. . Furthermore, since an exothermic reaction and an endothermic reaction occur simultaneously in the reaction region, thermal neutralization occurs and operation in a thermal equilibrium state is possible. Therefore, for example, the temperature rise in the reaction region is considerably suppressed compared to the case where a region for performing the catalytic combustion reaction alone is provided in the reactor, and the selection of the heat-resistant material used for the reactor and the heat-resistant structure of the reactor itself are much higher. Equipment costs can be reduced because it is not necessary to use specifications. In addition, the temperature of the raw material gas supplied to the catalyst layer inlet can be lowered, soot generation due to thermal decomposition of hydrocarbons can be suppressed, and the risk of ignition can be avoided.

The fluid mainly containing H ₂ O can use water or water vapor.

  Next, the best mode for carrying out the present invention will be described.

  FIG. 1 is a configuration diagram showing an example of a carbon monoxide gas generator 100 to which the present invention is applied.

  This carbon monoxide gas generator 100 uses a hydrocarbon-based gas, an oxygen-based gas, and water vapor as a raw material gas, the raw material gas is introduced, and the raw material gas is brought into contact with a catalyst to cause a combustion reaction of the hydrocarbon-based gas. And a reactor 51 that generates carbon monoxide gas as a mixed gas rich in hydrogen gas and having a high carbon monoxide gas concentration by causing a shift reaction.

  In the reactor 51, the hydrocarbon-based gas supplied from the hydrocarbon supply path 56 and the water vapor supplied from the water vapor supply path 63 are mixed, and the mixed gas is supplied to the mixed gas flow path 64 to which the mixed gas is supplied. The oxygen supply path 59 joins and is further introduced into the reactor 51 from the source gas supply path 65 as a source gas mixed with oxygen gas.

  The reformed gas, which is a gas mixture rich in hydrogen gas and having a high carbon monoxide gas concentration generated by reaction in the reactor 51, is led out from the reformed gas path 72 and passes through the gas-liquid separator 71 to the first PSA device 73. Then, after passing through the second PSA device 74, the product gas is discharged as carbon monoxide gas and hydrogen gas.

  The reformed gas path 72 is provided with a first heat exchanger 76, a second heat exchanger 77, and a third heat exchanger 78. The heat of the reformed gas is recovered and used for preheating or reforming the raw material. The quality gas is cooled.

  The hydrocarbon-based gas is supplied from a cylinder or a conduit (not shown), compressed to a predetermined pressure by the compressor 52, adjusted to a predetermined flow rate by the flow rate adjusting valve 54, and the reformed gas by the first heat exchanger 76. Is preheated to a predetermined temperature by the hydrocarbon preheater heater 55, desulfurized by the desulfurizer 53, and then supplied by the hydrocarbon supply path 56. The desulfurizer 53 may be one that performs hydrodesulfurization, or one that performs normal temperature adsorptive desulfurization filled with an adsorbent such as activated carbon or zeolite.

  As the hydrocarbon gas, it is possible to use hydrocarbon gases such as natural gas, butane gas, methane gas, etc. as well as hydrocarbon gases that are generally supplied as social infrastructure such as propane gas and city gas. In this example, an example using natural gas is described.

  The oxygen-based gas is supplied from an oxygen cold evaporator or the like (not shown), adjusted to a predetermined flow rate by a flow rate adjusting valve 58, and supplied by an oxygen supply path 59.

  As the oxygen-based gas, industrial pure oxygen can be preferably used. However, as long as the oxygen concentration is as high as 21% or more, oxygen-based gas may be mixed with some impurities or other gases. It can be used as

  The steam is preheated by supplying pure water with the pump 60, exchanging heat with the reformed gas by the second heat exchanger 77, and further heated by the pure water heater 57 and the steam heater 62 to form steam. Is adjusted to a predetermined flow rate by the flow rate adjusting valve 61 and supplied by the water vapor supply path 63.

  The steam supply path 63, the hydrocarbon supply path 56, and the oxygen supply path 59 are first provided with a mixed gas flow path 64 in which the steam supply path 63 and the hydrocarbon supply path 56 are joined. A source gas supply path 65 is provided by merging with the supply path 59. As a result, the raw material gas is configured such that a hydrocarbon gas and water vapor are mixed in advance, and an oxygen-based gas is merged therein and introduced into the reactor 51.

  The mixed gas flow path 64 is provided with a preheating heater 66 for preheating a mixed gas of hydrocarbon gas and water vapor to a predetermined preheating temperature. A raw material gas obtained by adding an oxygen-based gas to the mixed gas preheated to a predetermined temperature by the preheater 66 is introduced into the reactor 51.

  The source gas may be configured such that an oxygen-based gas and water vapor are mixed in advance, and a hydrocarbon-based gas is merged therein and introduced into the reactor 51. Alternatively, the oxygen-based gas, the water vapor, and the hydrocarbon-based gas may be combined and introduced into the reactor 51 at the same time.

The mixing ratio of the hydrocarbon-based gas, oxygen-based gas, and water vapor in the raw material gas is set by adjusting the flow rates of the hydrocarbon-based gas, oxygen-based gas, and water using the flow rate adjusting valves 54, 58, and 61, respectively.

That is, the raw material gas, and O ₂ of the oxygen-based gas molar ratio of C hydrocarbon gas becomes 0.3 to 0.5 in O _{2 /} C, and of H _{2 O} water vapor carbide The mixing ratio of hydrocarbon-based gas, oxygen-based gas, and water vapor is set so that the molar ratio with C in the hydrogen-based gas is 0.5 or less in terms of H ₂ O / C. That is, in order to increase the yield of CO, it is better to be low, and a certain amount of H ₂ O is necessary in relation to the temperature. Therefore, H ₂ O / C is preferably 0.5 or less. Further, if O ₂ / C exceeds 0.5, the hydrogen enters the hydrogen combustion region and the temperature becomes high, so it is preferable that O ₂ / C be 0.3 or more and 0.5 or less. The molar ratio of C of between _{H 2} O hydrocarbon gas in the steam _is preferably set to be 0.05 to 0.3 with _H 2 O / C.

For example, when the hydrocarbon gas is methane gas (CH ₄ ), since C in methane is 1, the mixing ratio is determined by the following equations (1) and (2). O ₂ / C is 0.3 to 0.5, that is, O ₂ is mixed at a ratio of 0.3 to 0.5 mol with respect to 1 mol of methane, and H ₂ O / C = 0.5 or less, that is, methane H ₂ O is mixed to 0.5 mol or less with respect to 1 mol.
O ₂ / C = [O ₂ ] / (1 × [CH ₄ ]) = 0.3 to 0.5 (1)
H ₂ O / C = [H ₂ O] / (1 × [CH ₄ ]) ≦ 0.5 (2)
[O ₂ ]: Number of moles of O ₂ [CH ₄ ]: Number of moles of CH ₄ [H ₂ O]: Number of moles of H ₂ O

Similarly, for example, when the hydrocarbon gas is propane gas (C ₃ H ₈ ), C in propane is 3, so the mixing ratio is determined by the following formulas (3) and (4). O ₂ / C is 0.3 to 0.5, that is, O ₂ is mixed at a ratio of 0.9 to 1.5 mol with respect to 1 mol of propane, and H ₂ O / C = 0.5 or less, that is, propane of _{H 2} O are mixed so as to be 1.5 mol or less relative to 1 mol.
O ₂ / C = [O ₂ ] / (3 × [C ₃ H ₈ ]) = 0.3 to 0.5 (3)
H ₂ O / C = [H ₂ O] / (3 × [C ₃ H ₈ ]) ≦ 0.5 (4)
[O ₂ ]: Number of moles of O ₂ [C ₃ H ₈ ]: Number of moles of C ₃ H ₈ [H ₂ O]: Number of moles of H ₂ O

In addition, this apparatus detects the flow rate variation of the hydrocarbon gas in the flow rate adjustment valve 54 and maintains the mixing ratio in accordance with the variation in the supply amount of the hydrocarbon gas, so that the oxygen gas flow rate adjustment valve 58 is maintained. And a flow rate controller (not shown) for controlling the supply amount of the source gas so as to automatically change the supply amount of the oxygen-based gas and water by adjusting the flow rate adjustment valve 61 of water.

The reactor 51 is filled with a Rh-modified (Ni—CeO ₂ ) —Pt catalyst as a catalyst. By using the Rh-modified (Ni—CeO ₂ ) —Pt catalyst, the hydrocarbon gas combustion reaction and the shift reaction are simultaneously performed in the same reaction region.

  The reactor 51 detects the supply temperature of the raw material gas to the reactor 51, that is, the temperature on the inlet side, and controls the preheating heater 66 so that the supply temperature of the raw material gas becomes 250 to 450 ° C. A controller 68 is provided.

  The reactor 51 is provided with a starter heater 69 that preheats a reaction region filled with a catalyst while flowing a nitrogen gas supplied from a nitrogen gas cylinder (not shown) when the apparatus is started. The starter heater 69 heats the internal temperature until it reaches about 200 to 300 ° C. necessary for starting the reaction of the raw material gas, and is similarly controlled by the temperature controller 68.

In the reactor 51, the hydrocarbon combustion reaction and the shift reaction are simultaneously performed in one reaction region by the Rh-modified (Ni—CeO ₂ ) —Pt catalyst.

That is, a combustion reaction in which part of the hydrocarbon is completely burned to convert the hydrocarbon into CO and H ₂ O, and each of CO ₂ and H ₂ O generated by this combustion reaction is further reacted with the remaining hydrocarbon. The reforming reaction that converts H ₂ into CO is allowed to proceed on the catalyst, and the hydrocarbon is converted into H ₂ and CO for reforming.

For example, the case where the hydrocarbon is methane will be described as an example, and the reaction is generally expressed as the following equation (5), but in reality, it is a combustion reaction as expressed by equations (6) to (8). It is a sequential reaction in which the produced CO ₂ and H ₂ O further undergo a metamorphic reaction with CH ₄ to convert to CO and H ₂ .
CH ₄ + 2O ₂ → 4CO + 8H ₂ (5)
CH ₄ + 2O ₂ → CO ₂ + 2H ₂ O (6)
CH ₄ + CO ₂ → 2CO + 2H ₂ (7)
2CH ₄ + 2H ₂ O → 2CO + 6H ₂ (8)

In the contact reaction between CH ₄ and O ₂ , CO ₂ or 2H ₂ O can be further supplied to the system. In this case, the supply amount of O ₂ can be reduced in accordance with the supply amount of CO ₂ or 2H ₂ O.

The reaction temperature is preferably 350 to 900 ° C, particularly 400 to 800 ° C. The combustion reaction of CH ₄ and O ₂ is an exothermic reaction, and the modification reaction of CH ₄ and H ₂ O is an endothermic reaction. As described above, the reaction region in the reactor 51 is preheated to 200 to 300 ° C. when the apparatus is started up, and the supply temperature of the raw material gas is controlled to be 250 to 450 ° C. Will be in thermal equilibrium and proceed simultaneously. Note that the reaction temperature deficiency may be externally heated. The reaction pressure is usually a pressurized condition (for example, 0.3 to 0.4 MPa), but may be a normal pressure condition.

The composition of the reformed gas obtained by reforming the combustion reaction and the shift reaction is approximately 64% H ₂ + 26% CO + 6% CO ₂ + 4% CH _{4 on} a dry basis when natural gas is used as a raw material, and the remainder is impure. Minutes. The temperature of the reformed gas at the outlet of the reactor 51 is about 700 to 800 ° C.

The Rh-modified (Ni—CeO ₂ ) —Pt catalyst is obtained, for example, by supporting Rh on an alumina support surface having an appropriate porosity, then supporting Pt, and further supporting Ni and CeO ₂ simultaneously. It is done. However, various variations are possible for the selection of the material and shape of the carrier, the presence / absence of coating formation, and the selection of the material.

Rh is supported by impregnating an aqueous solution of a water-soluble salt of Rh, followed by drying, firing, and hydrogen reduction. Pt is supported by impregnating an aqueous solution of a Pt water-soluble salt, followed by drying, firing, and hydrogen reduction. Simultaneous loading of Ni and CeO ₂ is performed by impregnating a mixed aqueous solution of a water-soluble salt of Ni and a water-soluble salt of Ce, followed by drying, firing, and hydrogen reduction.

The target Rh-modified (Ni—CeO ₂ ) -Pt catalyst is obtained by the procedure exemplified above. The composition of each component is Rh: Ni: CeO ₂ : Pt = (0.05-0.5) :( 3.0-10.0) :( 2.0-8.0) :( 0 .3-5.0), preferably Rh: Ni: CeO ₂ : Pt = (0.1-0.4) :( 4.0-9.0) :( 2.0-5.0): It is preferable to set to (0.3-3.0).

  It should be noted that the hydrogen reduction treatment at each stage in the above may be omitted, and the catalyst may be used after hydrogen reduction at a high temperature in actual use. Even when the hydrogen reduction treatment is performed in each stage, the catalyst can be further reduced with hydrogen at a high temperature before use.

In the carbon monoxide generation apparatus and method of the present embodiment, a branch path is formed downstream of the steam heater 62 in the steam supply path 63, and mainly contains H ₂ O downstream of the reactor 51 or the reaction step. A water vapor introduction path 67 for introducing water vapor as a fluid is provided. Thereby, the steam heated by the steam heater 62 can be introduced into the high-temperature reformed gas discharged from the reactor 51. The flow rate of water vapor introduced downstream of the reactor 51 or the reaction step is adjusted by a flow rate adjusting valve 70 provided in the water vapor introduction path 67.

  The joining position of the steam introduction passage 67 with respect to the reformed gas passage 72 is the same as the inlet of the first heat exchanger 76 on the most upstream side among the plurality of heat exchangers 76, 77, 78 provided in the reformed gas passage 72. It arrange | positions between the exits of the reactor 51. FIG.

  The reformed gas obtained as described above, that is, the mixed gas rich in hydrogen gas and having a high carbon monoxide gas concentration, is cooled by the third heat exchanger 78 for cooling, and water is removed by the gas-liquid separator 71. After that, it is introduced into the first PSA device 73.

The mixed gas rich in hydrogen gas and having a high carbon monoxide gas concentration removes H ₂ O, CO ₂ , CH _4, etc. by the first PSA device 73, and then turns into a product carbon monoxide gas and hydrogen gas by the second PSA device 74. To be separated.

The first PSA device 73 is configured by arranging a plurality of (four in this example) adsorption towers 79 in parallel. Each of the adsorption towers 79 is filled with an adsorbent such as activated carbon, molecular sieve, zeolite, etc., and the mixed gas produced in the reactor 51 and rich in hydrogen gas and having a high carbon monoxide gas concentration is used as an adsorbent layer. By passing it, H ₂ O, CO ₂ , CH _{4 and the} like are adsorbed by the adsorbent and removed. The _{H 2 O, CO 2, CH} 4 , etc. adsorption tower 79 that has been adsorbed on the adsorbent is by sucking the adsorption tower 79 by a vacuum pump _{80, H 2 O, CO 2} , CH adsorbent such as ₄ And then discharged as off-gas.

H ₂ O, CO ₂ , CH _4, etc. are adsorbed and removed by the first PSA device 73 by the first PSA device 73, and the mixed gas mainly becomes a mixed gas of carbon monoxide gas and hydrogen gas, and is introduced into the second PSA device 74.

  The second PSA device 74 is configured by arranging a plurality of (four in this example) adsorption towers 81 in parallel. Each of the adsorption towers 81 is filled with an adsorbent such as activated carbon, molecular sieve, or zeolite, and the mixed gas of carbon monoxide gas and hydrogen gas discharged from the first PSA device 73 passes through the adsorbent layer. By doing so, the carbon monoxide gas is adsorbed by the adsorbent and separated. The adsorption separation of the carbon monoxide gas is performed by introducing the gas discharged from the adsorption tower 81 into the adsorption tower 81 again by the circulation compressor 86 and circulating it repeatedly a plurality of times, and the carbon monoxide concentration is sufficiently lowered. The remaining hydrogen gas is recovered as product hydrogen gas.

  The carbon monoxide gas adsorbed and separated in each of the adsorption towers 81 is sucked into the adsorption tower 81 by a vacuum pump 82 to desorb the carbon monoxide from the adsorbent, and passes through the buffer tank 83 and the compressor 84 to be a product. The product is stored in the tank 85 as product carbon monoxide gas.

  As described above, the carbon monoxide gas generation apparatus and method according to the present embodiment introduces water vapor into the reactor 51 or downstream of the reaction step, so that the carbon on the metal surface such as the inside of the pipe downstream of the reactor 51 can be obtained. Is effectively prevented from precipitating. For this reason, it is possible to operate under conditions where the generation potential of carbon monoxide gas is high, and maintenance such as removal of pollutants can be greatly reduced. Thus, since it is possible to suppress the precipitation of carbon by introducing water vapor downstream of the reactor 51 or the reaction process, it becomes possible to suppress the amount of water vapor introduced into the reactor 51 or the reaction process. Alternatively, the carbon monoxide concentration of the reformed gas obtained by the reaction process can be greatly improved, and the yield of carbon monoxide can be greatly improved.

  Heat exchangers 76, 77, 78 for recovering heat generated in the reactor 51 are provided downstream of the reactor 51, and the outlet of the reactor 51 and the inlet of the first heat exchanger 76 on the most upstream side are provided. When steam is introduced between the heat exchangers 76, 77 and 78 provided downstream of the reactor 51 in order to recover the heat of the reactor 51, it is effectively prevented from being contaminated by carbon deposition. In addition to enabling operation under conditions where carbon monoxide gas generation potential is high, maintenance such as removal of pollutants can be greatly reduced.

Raw material gas introduced into the reactor 51 is such that the molar ratio of C of between H _{2 O} hydrocarbon gas of water vapor becomes 0.5 or less in H _{2 O} / C, a hydrocarbon gas When the mixing ratio of the oxygen-based gas and water vapor is set, the carbon monoxide gas concentration in the generated mixed gas becomes high. Further, since a high temperature is obtained in the reactor 51, the heat obtained from the mixed gas discharged from the reactor 51 can be used for heating the raw material and for heating the water vapor introduced downstream of the reactor.

Raw material gas introduced into the reactor 51 is such that the molar ratio of O ₂ in the oxygen-based gas and C of the hydrocarbon-based gas is 0.3 to 0.5 at a O _{2 /} C, carbonized When the mixture ratio of hydrogen gas, oxygen gas and water vapor is set, it prevents excessive heat generation due to internal combustion reaction and prevents catalyst damage. Can be maintained.

When the reactor 51 uses the Rh-modified (Ni—CeO ₂ ) —Pt catalyst, the combustion reaction and the shift reaction of the hydrocarbon gas are simultaneously performed in the same reaction region. By simultaneously performing the exothermic combustion reaction and the endothermic modification reaction in the same reaction region, the heat energy generated in the combustion reaction can be used as a heat source for the modification reaction, resulting in extremely high energy efficiency. Furthermore, since an exothermic reaction and an endothermic reaction occur simultaneously in the reaction region, thermal neutralization occurs and operation in a thermal equilibrium state is possible. Therefore, for example, the temperature rise in the reaction region is considerably suppressed as compared with the case where a region for performing the catalytic combustion reaction alone is provided in the reactor 51, and the selection of the heat-resistant material used for the reactor 51 and the heat-resistant structure of the reactor 51 itself. The equipment cost can be reduced because it is not necessary to use a high temperature specification. In addition, the temperature of the raw material gas supplied to the catalyst layer inlet can be lowered, soot generation due to thermal decomposition of hydrocarbons can be suppressed, and the risk of ignition can be avoided.

  In the case where the raw material gas is configured so that hydrocarbon gas and water vapor are mixed in advance, and oxygen-based gas is merged therein and introduced into the reactor 51, hydrocarbon-based gas which is a combustible gas The flow path through which the mixed gas of oxygen and oxygen gas passes can be shortened, which is advantageous in terms of safety.

  In the case where the raw material gas is configured such that an oxygen-based gas and water vapor are mixed in advance, and the hydrocarbon-based gas is merged therein and introduced into the reactor 51, the hydrocarbon-based hydrocarbon-based gas Since the oxygen concentration of the mixed gas in which the gas is merged is lowered, the explosion limit is further lowered, which is advantageous in terms of safety.

  When the supply amount of the raw material gas is controlled so as to automatically change the supply amount of the oxygen-based gas and water according to the change of the supply amount of the hydrocarbon-based gas, a gas having a substantially constant CO concentration is always used. The yield can be varied while obtaining.

  A preheating heater 66 for preheating the raw material gas introduced into the reactor 51 is provided, and when the preheating heater 66 is controlled so that the supply temperature of the raw material gas to the reactor 51 is 250 to 450 ° C., it is always efficient. Operation in a good thermal equilibrium state is possible.

  Further, since it is possible to suppress the precipitation of carbon by introducing water vapor downstream of the reactor 51 or the reaction step, it becomes possible to suppress the amount of water vapor introduced into the reactor 51 or the reaction step, and depending on the operating conditions, It is also possible to omit the gas-liquid separator 71 arranged on the upstream side of the first PSA device 73.

  FIG. 2 is a diagram illustrating a carbon monoxide gas generation apparatus and method according to the second embodiment of the present invention.

In this example, a pure water introduction path 88 and a pure water blower 87 for introducing pure water as a fluid mainly containing H ₂ O are provided downstream of the reactor 51 or the reaction step. Thereby, pure water can be introduced into the high-temperature reformed gas discharged from the reactor 51. Other than that is the same as that of the said embodiment, and attaches | subjects the same code | symbol to the same part. Also in this example, the same operational effects as the above-described embodiment are obtained.

FIG. 3 shows the carbon monoxide gas generating apparatus 100 in which carbon monoxide is produced by changing the molar ratio H ₂ O / C between H ₂ O in water vapor and C in hydrocarbon-based gas using propane gas as a raw material. The result of generating gas is shown. At this time, O ₂ / C was set to 0.40, the supply temperature of the raw material gas was set to 400 ° C., and the reforming pressure was set to 0.3 MPa.

As can be seen from the figure, the CO concentration in the reformed gas generated when H ₂ O / C was 0.5 or less was high, and the CO yield could be increased.

FIG. 4 shows that in the carbon monoxide gas generator 100, propane gas is used as a raw material, and the molar ratio O ₂ / C between O ₂ in the oxygen-based gas and C in the hydrocarbon-based gas is changed. The results of the generation of carbon monoxide gas are shown. At this time, H ₂ O / C was set to 0.5, the supply temperature of the raw material gas was set to 400 ° C., and the reforming pressure was set to 0.3 MPa.

As can be seen from the figure, the CO concentration in the reformed gas generated when O ₂ / C was 0.3 or more and 0.5 or less was high, and the yield of CO could be increased.

FIG. 5 shows carbon monoxide gas generation apparatus 100 using natural gas as a raw material and changing the molar ratio H ₂ O / C between H ₂ O in water vapor and C in hydrocarbon-based gas. The result of generating gas is shown. At this time, O ₂ / C was set to 0.40, the supply temperature of the raw material gas was set to 400 ° C., and the reforming pressure was set to 0.3 MPa.

As can be seen from the figure, the CO concentration in the reformed gas generated when H ₂ O / C was 0.5 or less was high, and the CO yield could be increased.

6, in the carbon monoxide gas generator 100, the natural gas as a raw material, changing the molar ratio O _{2 /} C and C of the raw material oxygen-based O ₂ and hydrocarbon gas in the gas in the gas The results of the generation of carbon monoxide gas are shown. At this time, H ₂ O / C was set to 0.5, the supply temperature of the raw material gas was set to 400 ° C., and the reforming pressure was set to 0.3 MPa.

As can be seen from the figure, the CO concentration in the reformed gas generated when O ₂ / C was 0.3 or more and 0.5 or less was high, and the yield of CO could be increased.

It is a figure which shows one Embodiment of the carbon monoxide gas generator of this invention. It is a figure which shows 2nd Embodiment of the carbon monoxide gas generator of this invention. Shows the results of a propane gas as a raw material, was by changing the H 2 _{O /} C to generate carbon monoxide gas. Shows the results of a propane gas as a raw material, was by changing the O 2 _{/ C} to generate carbon monoxide gas. Natural gas as a raw material, shows the results caused the carbon monoxide gas by changing the H 2 _{O /} C FIG. Natural gas as a raw material, showing the by changing the O 2 _{/ C} results caused the carbon monoxide gas FIG.

Explanation of symbols

51: Reactor 52: Compressor 53: Desulfurizer 54: Flow rate adjusting valve 55: Hydrocarbon preheating heater 56: Hydrocarbon supply path 57: Pure water heater 58: Flow rate adjusting valve 59: Oxygen supply path 60: Pump 61: Flow rate Control valve 62: Steam heater 63: Water vapor supply path 64: Mixed gas flow path 65: Raw material gas supply path 66: Preheating heater 67: Water vapor introduction path 68: Temperature controller 69: Starter heater 70: Flow rate adjustment valve 71: Gas-liquid Separator 72: Reformed gas path 73: First PSA device 74: Second PSA device 76: First heat exchanger 77: Second heat exchanger 78: Third heat exchanger 79: Adsorption tower 80: Vacuum pump 81: Adsorption tower 82: vacuum pump 83: buffer tank 84: compressor 85: product tank 86: recycle compressor 87: pure water bubbler 88: pure water introducing passage 100: carbon monoxide gas generator

Claims (6)

A hydrocarbon gas, an oxygen gas, and water vapor are introduced as a raw material gas, and the raw material gas is brought into contact with a catalyst to cause a combustion reaction and a shift reaction of the hydrocarbon gas. A reactor for generating carbon monoxide gas as a mixed gas having a high gas concentration, and a separation device for separating carbon monoxide gas as a product gas from the mixed gas generated in the reactor ,
A carbon monoxide gas generator, wherein a fluid mainly containing H ₂ O is introduced downstream of the reactor as a fluid for suppressing carbon deposition on the metal surface inside the pipe . A heat exchanger for recovering heat generated in the reactor is provided downstream of the reactor, and a fluid mainly containing H ₂ O is introduced between the outlet of the reactor and the inlet of the heat exchanger. The carbon monoxide gas generator according to 1. Raw material gas introduced into the reactor, so that the molar ratio of C of between H _{2 O} hydrocarbon gas of water vapor becomes 0.5 or less in H _{2 O} / C, hydrocarbon gas and oxygen 3. A carbon monoxide gas generator configured to set a mixing ratio of a system gas and water vapor. Raw material gas introduced into the reactor, so that the molar ratio of O ₂ in the oxygen-based gas and C of the hydrocarbon-based gas is 0.3 to 0.5 at a O _{2 /} C, hydrocarbons The carbon monoxide gas generator according to any one of claims 1 to 3, wherein a mixing ratio of a system gas, an oxygen-based gas, and water vapor is set. The reactor is, Rh modified (Ni-CeO 2) by using _-Pt catalyst, according to claim 1 adapted to perform simultaneously the shift reaction and the combustion reaction of hydrocarbon gas in the same reaction region The carbon monoxide gas generator according to any one of 4. A hydrocarbon gas, an oxygen gas, and water vapor are introduced as a raw material gas, and the raw material gas is brought into contact with a catalyst to cause a combustion reaction and a shift reaction of the hydrocarbon gas. Performing a reaction step of generating carbon monoxide gas as a mixed gas having a high gas concentration, and a separation step of separating carbon monoxide gas as a product gas from the mixed gas generated in the reaction step ,
A carbon monoxide gas generation method characterized by introducing a fluid mainly containing H ₂ O as a fluid for suppressing carbon deposition on the metal surface inside the pipe downstream of the reaction step.

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