JP2001342003A - Method of production for gasoline, gas oil and synthesis gas for kerosene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of production for gasoline, gas oil and synthesis gas for kerosene, wherein the method has no limitation of choosing a location being adjacent to carbon dioxide source like ammonia production plant, and is capable of economically producing the synthesis gas having a suitable molar ratio of hydrogen/carbon monoxide for synthesizing gasoline, gas oil and kerosene in a system of the Fischer-Tropsch reaction at any location, by producing carbon dioxide in a plant producing a synthesis gas containing the system of the Fischer-Tropsch reaction. SOLUTION: By producing the synthesis gas containing carbon monoxide and hydrogen being used for synthesizing gasoline, gas oil and kerosene in the system of the Fischer-Tropsch reaction, the method is characterized by producing the synthesis gas containing carbon monoxide and hydrogen at a ratio of hydrogen/carbon monoxide =1-2.5, wherein the synthesis gas is produced by supplying a steam-added natural gas to a reformer, together with recovering carbon dioxide from a combustion gas generated in a combustion radiation part for heating the reformer, and supplying carbon dioxide to the upstream side of the reformer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a synthesis gas used for synthesizing gasoline, light oil and kerosene in a Fischer-Tropsch reaction system.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open Publication No.
Hydrogen (H_Two) And carbon monoxide (CO)
A synthetic gas is produced and from this syngas
GTL (Gas to Liquid) process in the reaction system
A method for synthesizing gasoline or the like is disclosed. The combination
The formed gas is supplied to the reformer containing the reforming catalyst by methane.
Supply natural gas and water vapor mainly containing
The natural gas is heated by heating the homer to a predetermined temperature.
Mainly produced by reacting hydrocarbons and water vapor in
I have. However, the synthesis gas produced by this method is
For example, the molar ratio of H _Two: CO: CO_Two= 5: 1: 0.5
In order to synthesize the gasoline etc., hydrogen is
Too much. That is, the Fischer-Tropsch reaction system
In the case where a cobalt catalyst is used in
_TwoThe optimal molar ratio of / CO is 2. In addition, iron-based catalysts
H in the synthesis gas_TwoThe optimal molar ratio of / CO is 1 to
2.

For this reason, the publication discloses that CO and H ₂ suitable for synthesizing gasoline and the like in a Fischer-Tropsch reaction system are obtained by adding oxygen to the reformer to partially oxidize the reformer.
It is disclosed to produce a synthesis gas containing However, since the oxygen plant is a technology for separating oxygen from air by low-temperature treatment, there is a problem that not only a large amount of energy is consumed but also the plant itself is expensive.

On the other hand, "Chemical Engineering Progres"
s ", Goff and Wang, August 1987, pp. 46-53, discloses a process for syngas production. In the left column of pg. It is stated that a ₂ / CO ratio is produced by reacting with 1-2 hydrogen and carbon monoxide.

In the right column of page 49 of the document, the method 4
When supplying natural gas after desulfurization to the steam reformer as A, carbon dioxide is supplied from outside the system (for example, an adjacent ammonia plant) to the natural gas,
It is described that steam and carbon dioxide are reacted to produce a syngas comprising hydrogen and carbon monoxide with an H ₂ / CO ratio of 1-2. This method is described in the fourth document of the same document.
Although beneficial, as described in page 9, right column, lines 8-11, in minimizing excess product hydrogen without the need for oxygen addition, a major disadvantage is the CO ₂ source (eg, Adjacent ammonia plant). For this reason, there is a problem that the method 4A cannot be realized except in a place where the CO ₂ source is adjacent such as an ammonia plant.

[0006]

[SUMMARY OF THE INVENTION The present invention, by raising the CO ₂ in the manufacturing plant of synthesis gas containing Fischer-Tropsch reaction system, is constrained to the location where CO ₂ source is adjacent, such as ammonia plant To provide a method capable of inexpensively producing a synthesis gas having an H ₂ / CO molar ratio suitable for synthesizing gasoline, gas oil and kerosene in a Fischer-Tropsch reaction system anywhere. It is.

[0007]

A gasoline according to the present invention,
The production method for gas and kerosene synthesis gas is
Gasoline Tropsch reaction system in producing a synthesis gas containing CO and H ₂ which are used to synthesize the gas oil and kerosene supplies the natural gas vapor is added to the reformer, the reformer By recovering carbon dioxide from the flue gas generated in the combustion radiator for heating and supplying the carbon dioxide to the upstream side of the reformer, CO and H ₂ are contained, and the molar ratio of H ₂ / CO is increased. The ratio is 1
It is characterized by producing 2.5 synthesis gas.

[0008] In the method for producing syngas according to the present invention, carbon dioxide in the syngas produced in the reformer is recovered and allowed to circulate upstream of the reformer.

In the method for producing a synthesis gas according to the present invention, the process for recovering carbon dioxide from the combustion exhaust gas for heating the reformer and the process for recovering carbon dioxide in the synthesis gas are the same. It is preferable to carry out using. In the process of recovering carbon dioxide in synthesis gas, amine-based absorption solution and potassium carbonate-based absorption solution are used, and in the process of recovering carbon dioxide from combustion exhaust gas, the conventionally used monoethanolamine absorption solution is used. In addition, a new alkanolamine with little deterioration is used.

In the method for producing synthesis gas according to the present invention, when synthesizing the synthesis gas produced in the reformer into gasoline, light oil and kerosene in a Fischer-Tropsch reaction system, the carbon dioxide produced in the reaction system is produced. It is preferable to circulate a purge gas containing the gas upstream of the reformer.

In the method for producing syngas according to the present invention, a pre-reformer is disposed upstream of the reformer, and the natural gas to which steam has been added is passed through the pre-reformer via the pre-reformer. Preferably, the carbon dioxide is supplied to a reformer and the carbon dioxide recovered from the combustion exhaust gas is supplied to a flow path between the reformer and the preliminary reformer.

In the method for producing synthesis gas according to the present invention, in the step of adding steam to the natural gas, a humidifier is disposed downstream of the reformer, and the synthesis gas from the reformer is supplied to the humidifier. And heating the humidifier by the waste heat thereof, and supplying the natural gas and water to the heated humidifier.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for producing gasoline, light oil and kerosene syngas according to the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a schematic diagram showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the first embodiment.

The reformer 10 includes a steam reforming reaction tube 11.
And a combustion radiating section 12 arranged around the reaction tube 11.
And a chimney 14 connected to the combustion radiating section 12 via a convection section (waste heat recovery section) 13. The reaction tube 11 is filled with, for example, a nickel-based catalyst.

The raw gas-introducing passageway 20 ₁ is connected to the upper end of the reaction tube 11 via the convection portion 13 of the reformer 10. In the passage 20 _1, it may be interposed desulfurizer (not shown). Steam (steam) introduction channel 2
0 ₂ is connected to the raw gas-introducing passageway 20 ₁ which is positioned on the upstream side of the convection portion 13. Flow path for fuel introduction 20 ₃
Is connected to the combustion radiating section 12 of the reformer 10.

The first carbon dioxide recovery device 31 _1, the provided convection section 13 of the reformer 10, to recover the carbon dioxide in the combustion exhaust gas of the convection portion 13. The first carbon dioxide recovery device 31 _1, the compressor 3 and then through the passageway 20 ₄
2 are connected. The compressor 32 is connected via the channel 20 ₅ to the raw gas-introducing passageway 20 ₁ which is upstream of the reformer 10.

[0018] Synthesis gas flow passage 20 _6, one end connected to the reaction tube 11 the lower end of the reformer 10, the other end for example Fischer cobalt-based catalyst is filled-Tropsch (FT) reaction system 33 It is connected. Note that this FT
The catalyst filled in the reaction system 33 is not limited to a cobalt-based catalyst, and for example, an iron-based catalyst can be used. Heat exchanger 3
4 and the second carbon dioxide recovery device 31 ₂ are successively disposed from the reformer 10 side to the synthesis gas flow passage 20 _6. The heat exchanger 34 has a passage 20 ₇ is crossed, for generating a high-pressure steam (steam) is heated, for example, boiler water flowing through the flow path 20 _7. The second carbon dioxide capture device 31 ₂ is connected to the compressor 32 by a flow path 20 _8.
Connected via Incidentally, for example, passage 20 ₉ boiler water is circulated its combustion exhaust gas of the convection portion 13 and the boiler water is heat exchanged intersects the convection unit 13 of the reformer 10, to cool the combustion exhaust gas The boiler water itself is heated to generate high-pressure steam (steam).

Next, a method for producing synthesis gas will be described with reference to the above-described synthesis plant shown in FIG.

[0020] First, combustion fuel is a fuel introducing passage 20 ₃
Is supplied to the combustion radiator 12 of the reformer 10, where it is combusted with air to heat the reaction tube 11 to a predetermined temperature. The combustion exhaust gas containing carbon dioxide generated in the combustion radiating section 12 reaches the chimney 14 via the convection section 13. The combustion exhaust gas is natural gas, and the flow passage 20 ₉ within is boiler water heat exchanger for circulating the cooling flowing through the raw gas-introducing passageway 20 ₁ while passing through the convection portion 13. Carbon dioxide cooled combustion exhaust gas is recovered by the first carbon dioxide recovery device 31 ₁ is supplied to the compressor 32 and then through the passageway 20 _4. The cooled combustion exhaust gas from which carbon dioxide has been removed is discharged from the chimney 14 to the atmosphere.

Natural gas containing methane as a main component is a raw material gas.
Flow path 20₁Supplied to At this time, the compressor
The carbon dioxide pressurized at 32_FiveVia via
A predetermined amount is added to the natural gas. In addition, steam (stee
Is a flow path 20 for introducing steam. _TwoThrough the natural gas
A predetermined amount is added. This steam is passed through the heat exchanger 34.
Produced by heat exchange of boiler water with synthesis gas
The steam and boiler water are combusted in the convection section 13 of the reformer 10.
Utilizes water vapor generated by heat exchange with flue gas
Is done.

[0022] Natural gas carbon dioxide and water vapor is added, the raw material gas flows through the introduction passage 20 ₁ is heated while passing through the convection portion 13 of the reformer 10 (preheating) Thereafter, it is supplied to the reaction tube 11. The natural gas, steam and carbon dioxide mainly containing methane (CH ₄ ) supplied to the reaction tube 11 of the reformer 10 are mainly subjected to steam reforming in the presence of a catalyst in the reaction tube 11. Then, it is converted into a synthesis gas containing hydrogen, carbon monoxide and carbon dioxide according to the following formulas (1) and (2) shown in the following equation (1).

[0023]

(Equation 1)

In formulas (1) and (2) of the reforming reaction, 4 mol of hydrogen is obtained by reacting 1 mol of methane with 2 mol of steam.
One mole of carbon dioxide is produced. However, in an actual reaction system, a composition close to the chemical reaction equilibrium composition determined by the temperature and pressure at the outlet of the reformer can be obtained. For this reason, when steam and carbon dioxide are added to the natural gas, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 is produced.

Since the reforming reaction is an endothermic reaction, the fuel gas and the air are burned by the combustion radiating section 12 of the reformer 10 so that the inside of the reaction tube 11 is, for example, 85 mm as described above.
Heat to 0-900C.

The resulting synthesis gas, synthesis gas via the flow passage 20 ₆ is supplied to the heat exchanger 34, wherein heating the boiler water flowing through the flow path 20 _7, generating a high-pressure steam At the same time, after cooling itself, it is supplied to the _second carbon dioxide recovery device 312. Here, the carbon dioxide in the synthesis gas is recovered, and water that has been concurrently produced is discharged outside the system through the passage 20 _10. The recovered carbon dioxide, the and then through the passageway 20 ₈ compressor 32
Is sent to the boosted with recovered carbon dioxide in the first carbon dioxide recovery device 31 ₁ is added to natural gas in the flow path 20 ₅ via in the raw gas-introducing passageway 20 ₁ .

The synthesis gas of carbon dioxide has been removed, the flow path 20 ₆ via by for example cobalt catalyst is fed to the Fischer-Tropsch (FT) reaction system 33 which is filled, wherein the hydrogen in the synthesis gas Reacts with carbon monoxide to synthesize gasoline, light oil and kerosene.

The above, when performing the reforming reaction is supplied to the reaction tube 11 of the reformer 10 natural gas steam is added through passage 20 _first source gas introduction according to the first embodiment, the modified Since the heat reaction is an endothermic reaction, a combustion radiating section 12 is provided for the purpose of heating the reaction tube 11 of the reformer 10, and the combustion exhaust gas discharged from the combustion radiating section 12 is cooled, and the carbon dioxide contained in the combustion exhaust gas is cooled. First carbon dioxide capture device 3
1 ₁ is recovered, after pressurized by the compressor 32, fed to the natural gas and the like and then through the passageway 20 ₅ flowing through the raw gas-introducing passageway 20 ₁ which is upstream of the reformer 10, Added.
In the second carbon dioxide recovery device 31 _2, the carbon dioxide in the synthesis gas obtained in the reformer 10 is recovered, and then through the passageway 20 ₈ sent to the compressor 32, the first carbon dioxide recovery device 31 ₁ is boosted with the recovered carbon dioxide is added to natural gas in the flow path 20 ₅ via in the raw gas-introducing passageway 20 _1. By supplying carbon dioxide to the steam-added natural gas in this way, a synthesis gas having a H ₂ / CO molar ratio of 1 to 2.5 can be produced. The synthesis gas having such a molar ratio of H ₂ / CO is supplied to, for example, a Fischer-Tropsch (FT) reaction system 33 filled with a cobalt catalyst to react hydrogen in the synthesis gas with carbon monoxide. Can synthesize gasoline, light oil and kerosene.

[0029] Thus, to procure carbon dioxide inside the production plant of synthesis gas containing Fischer-Tropsch reaction system (the reformer), i.e. it is possible to procure carbon dioxide on their own, CO _2, such as ammonia plant The source is not confined to the location adjacent to it, and the synthesis gas having a molar ratio of H ₂ / CO suitable for synthesizing gasoline, gas oil and kerosene in the Fischer-Tropsch reaction system can be produced at low cost anywhere. .

Example 1 In Example 1, the production of the synthesis gas of the first embodiment described above will be described more specifically with reference to the synthesis plant shown in FIG.

The fuel (natural gas) was supplied to the combustion radiator 12 of the reformer 10 under the condition of 625 kmol / hr, and was burned by the combustion radiator 12 together with air. Table 1 below shows natural gas, steam (steam) and carbon dioxide (recovered from the combustion exhaust gas and the synthesis gas of the reformer 10).
Raw material gas is supplied to the introducing flow channel 20 _1, to produce a synthesis gas by steam reforming in the reaction tube 11 of the reformer 10 under the conditions shown in. Table 1 shows the composition of the obtained synthesis gas.

[0032] Incidentally, Table 1 item (A) is natural gas supplied to the passage 20 _first source gas introduction, item (B) is water vapor supplied to the passage 20 _first source gas introduction (steam),
Item (C) carbon dioxide recovered by the first carbon dioxide recovery device 31 ₁ from the combustion exhaust gas generated in the combustion radiation portion 12 of the reformer 10, item (D) the second carbon dioxide from the synthesis gas carbon dioxide recovered by the recovery device 31 _2, item (E) the first, second carbon dioxide recovery device 3 is supplied with pressurized by the compressor 32 to the raw gas-introducing passageway 20 ₁
The carbon dioxide recovered in ₁₁ and 31 ₂ , item (F) is produced in the reformer 10 and supplied to the _second carbon dioxide recovery device 312 through the heat exchanger 34, and item (G) is water discharged from the second carbon dioxide recovery device 31 _2, item (H) is fed to the FT reaction system 33 represents the synthesis gas, the carbon dioxide has been removed in the second carbon dioxide recovery device 31 ₂ . These items (A) to (H) are shown in FIG.
It appends to.

[0033]

[Table 1]

As is clear from Table 1 above, steam was added.
First and second carbon dioxide capture devices 31
₁, 31_TwoBy supplying the carbon dioxide
And H _TwoCan produce a synthesis gas with a / CO molar ratio of about 2.
You can see that.

(Second Embodiment) FIG. 2 is a schematic diagram showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the second embodiment. In FIG. 2, the same members as those in FIG. 1 described above are denoted by the same reference numerals, and description thereof will be omitted.

This synthesis plant is provided in a convection section 13 of the reformer 10 and contains a first carbon dioxide absorption tower containing an absorbing solution for absorbing carbon dioxide in the combustion exhaust gas of the convection section 13. 35 ₁ The first carbon dioxide absorption tower 35 second carbon dioxide absorption tower 35 ₂ absorbing solution and the same absorption liquid is contained in _1, downstream synthesis gas flow passage of the heat exchanger 34 20 ₆ It is interposed in. These first and second carbon dioxide absorption tower 35 _1, 35 ₂ has a passage 2
0 _11, 20 ₁₂ are connected to the absorbing solution regeneration device 31 ₃ through. The absorbing solution regeneration device 31 ₃ with carbon dioxide separation, absorption liquid after being recovered is returned through flow path 20 ₁₃ to the first carbon dioxide absorption tower 35 _1, and branched from the flow path 20 ₁₃ the sent back the second carbon dioxide absorption tower 35 ₂ through other passages 20 _14. The absorbing solution regeneration device 31 ₃ is connected to the compressor 32 through the passage 20 _15.

Next, a method for producing synthesis gas will be described with reference to the above-described synthesis plant shown in FIG.

Firstly, combustion fuel is a fuel introducing passage 20 ₃
Is supplied to the combustion radiator 12 of the reformer 10, where it is combusted with air to heat the reaction tube 11 to a predetermined temperature. The combustion exhaust gas containing carbon dioxide generated in the combustion radiating section 12 reaches the chimney 14 via the convection section 13. The combustion exhaust gas is natural gas, and the flow passage 20 ₉ within is boiler water heat exchanger for circulating the cooling flowing through the raw gas-introducing passageway 20 ₁ while passing through the convection portion 13. The carbon dioxide in the cooled combustion exhaust gas is absorbed by the carbon dioxide absorbing liquid in the _first carbon dioxide absorption tower 351. Absorbent that has absorbed carbon dioxide is supplied to the absorbing solution regeneration device 31 ₃ through the channel 20 _11, carbon dioxide is recovered. The recovered carbon dioxide is supplied to the compressor 32 and then through the passageway 20 _15. Absorbent liquid regeneration device 3
1 absorbent liquid carbon dioxide has been separated in ₃ is returned the to the first carbon dioxide absorption tower 35 ₁ through the flow path 20 _13. The cooled combustion exhaust gas from which carbon dioxide has been removed is discharged from the chimney 14 to the atmosphere.

Natural gas containing methane as a main component is a raw material gas.
Flow path 20₁Supplied to At this time, the compressor
The carbon dioxide pressurized at 32_FiveVia via
A predetermined amount is added to the natural gas. In addition, steam (stee
Is a flow path 20 for introducing steam. _TwoThrough the natural gas
A predetermined amount is added. This steam is passed through the heat exchanger 34.
Produced by heat exchange of boiler water with synthesis gas
The steam and boiler water are combusted in the convection section 13 of the reformer 10.
Utilizes water vapor generated by heat exchange with flue gas
Is done.

[0040] Natural gas carbon dioxide and water vapor is added, the raw material gas flows through the introduction passage 20 ₁ is heated while passing through the convection portion 13 of the reformer 10 (preheating) Thereafter, it is supplied to the reaction tube 11. The natural gas, steam and carbon dioxide mainly containing methane (CH ₄ ) supplied to the reaction tube 11 of the reformer 10 are mainly subjected to steam reforming in the presence of a catalyst in the reaction tube 11. And converted into a synthesis gas containing hydrogen, carbon monoxide and carbon dioxide according to the above formulas (1) and (2).

In the reforming reaction, when steam and carbon dioxide are added to the natural gas, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 is produced.

Since the reforming reaction is an endothermic reaction, fuel gas and air are burned by the combustion radiating section 12 of the reformer 10 as described above, so that the inside of the reaction tube 11 is, for example, 85%.
Heat to 0-900C.

The resulting synthesis gas, synthesis gas via the flow passage 20 ₆ is supplied to the heat exchanger 34, wherein heating the boiler water flowing through the flow path 20 _7, generating a high-pressure steam As it cools itself. Synthesis gas after cooling is fed to the absorption liquid second carbon dioxide absorption tower 35 in which the same absorption liquid is contained and ₂ of the first carbon dioxide absorption tower 35 _1, the carbon dioxide of the synthesis gas There is absorbed by the absorption solution, and water that has been concurrently produced is discharged outside the system through channels 20 _16. Absorbing solution having absorbed carbon dioxide, the absorbing solution regeneration device through the channel 20 ₁₂ 3
Is supplied to the 1 _3, carbon dioxide absorption solution with sent absorption liquid from the first carbon dioxide absorption tower 35 ₁ is separated and recovered. The recovered carbon dioxide flows into the channel 20 ₁₅
Via sent to compressor 32 where it is boosted further the channel 20 ₅ via the raw gas-introducing passage 2
0 is added to the natural gas in _one. Absorbent liquid regeneration device 3
1 absorbent liquid carbon dioxide has been separated in ₃ is returned the second carbon dioxide absorption tower 35 ₂ through the flow path 20 _14.

The synthesis gas of carbon dioxide has been removed, the flow path 20 ₆ via by for example cobalt catalyst is fed to the Fischer-Tropsch (FT) reaction system 33 which is filled, wherein the hydrogen in the synthesis gas Reacts with carbon monoxide to synthesize gasoline, light oil and kerosene.

As described above, according to the second embodiment, the first
As in the embodiment, a synthesis gas having a molar ratio of H ₂ / CO of 1 to 2.5 can be produced, and this synthesis gas is, for example, Fischer-Tropsch (F) filled with a cobalt catalyst.
T) Gasoline, light oil and kerosene can be synthesized by supplying the reaction system 33 with hydrogen in the synthesis gas and reacting with carbon monoxide.

The first and second carbon dioxide absorption towers 35
_1, the 35 ₂ performs the reformer 10 CO in combustion exhaust gas exhausted from the combustion radiation portion 12 of the absorption of carbon dioxide in the synthesis gas using the same absorption liquid, these absorbent solution One carbon dioxide absorption liquid regeneration device 31 ₃
, The synthesis plant can be simplified.

Example 2 In Example 2, the production of the synthesis gas of the second embodiment described above will be described more specifically with reference to a synthesis plant shown in FIG.

The fuel (natural gas) was supplied to the combustion radiator 12 of the reformer 10 under the condition of 625 kmol / hr, and was burned with the air in the combustion radiator 12. Table 2 below shows natural gas, steam (steam) and carbon dioxide (recovered from the combustion exhaust gas and the synthesis gas of the reformer 10).
Raw material gas is supplied to the introducing flow channel 20 _1, to produce a synthesis gas by steam reforming in the reaction tube 11 of the reformer 10 under the conditions shown in. Table 2 shows the composition of the obtained synthesis gas.

[0049] Incidentally, Table 2 item (A) is natural gas supplied to the passage 20 _first source gas introduction, item (B) is water vapor supplied to the passage 20 _first source gas introduction (steam),
Item (C) is carbon dioxide recovered at the same absorbed by the absorbing liquid absorbing solution regeneration device 31 ₃ is supplied with pressurized by the compressor 32 to the passage 20 _first source gas introduction, items (D) is modified Vessel 1
0 produced in the synthesis gas fed to the heat exchanger 34 through the second carbon dioxide absorption tower 35 _2, item (E) the second
Of water discharged from the carbon dioxide absorption tower 35 _2, item (F) is fed to the FT reaction system 33, a synthesis gas of carbon dioxide has been removed in the second carbon dioxide absorption tower 35 _2, represents. These items (A) to (F) are additionally shown in FIG.

[0050]

[Table 2]

[0051] By supplying the carbon dioxide recovered in the table as two clearly absorbed natural gas steam is added with the same absorbing liquid absorbing solution regeneration device 31 _3,
It can be seen that a synthesis gas having a H ₂ / CO molar ratio of about 2 can be produced.

(Third Embodiment) FIG. 3 is a schematic diagram showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the third embodiment. In FIG. 3, the same members as those in FIG. 1 described above are denoted by the same reference numerals, and description thereof will be omitted.

In this synthesis plant, a pre-reformer 36 is arranged upstream of the reformer 10. Raw gas-introducing passageway 20 ₁ is connected to the top of the pre-reformer 36. The pre-reformer 36 is connected to the upper end of the reaction tube 11 of the reformer 10 through the channel 20 _17. The flow path 20 ₁₇ is connected to the reaction tube 11 via the convection portion 13 of the reformer 10. The compressor 32 is connected to the flow path 2
0 ₅ via is connected to the channel 20 ₁₇ which connects the reformer 10 and the preliminary reformer 36.

Next, a method for producing a synthesis gas will be described with reference to the synthesis plant shown in FIG.

First, the fuel for combustion is supplied to the combustion radiating section 12 of the reformer 10 in the same manner as in the first embodiment, and
1 is heated to a predetermined temperature, generated by the combustion radiation unit 12, to recover the carbon dioxide in the cooled combustion exhaust gas at the first carbon dioxide recovery device 31 ₁ is supplied to the compressor 32.

[0056] Natural gas containing methane as a main component is fed to the passage 20 _first source gas introduction. At this time, the water vapor (steam) is added a predetermined amount in the natural gas through passage 20 ₂ introduced steam. Natural gas steam is added, heating while the source gas flows through the introduction passage 20 _1, passes through the convection portion 13 of the reformer 10 (preheating)
Then, it is supplied to the pre-reformer 36. In this pre-reformer 36, C such as ethane in natural gas is mainly used.
2 or more hydrocarbons of C1 methane and CO, is reformed into H _2.

[0057] Preliminary modified steam added natural gas is supplied to the reaction tube 11 of the reformer 10 through the channel 20 _17. At this time, carbon dioxide has been pressurized by the compressor 32 is added a predetermined amount to the pre-reformed steam added natural gas flowing through the said channel 20 ₁₇ and then through the passageway 20 _5.
Methane (CH) supplied to the reaction tube 11 of the reformer 10
₄ ) Natural gas, steam and carbon dioxide, whose main components are methane, are mainly steam reformed in the presence of a catalyst in the reaction tube 11, and are converted into hydrogen, monoxide according to the above formulas (1) and (2). It is converted to synthesis gas containing carbon and carbon dioxide.

In the reforming reaction, when steam and carbon dioxide are added to the natural gas, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 is produced.

Since the reforming reaction is an endothermic reaction, as described above, the combustion radiating section 12 of the reformer 10 burns the fuel gas and the air to cause the inside of the reaction tube 11 to reach, for example, 85%.
Heat to 0-900C.

[0060] The resulting synthesis gas, synthesis gas via the flow passage 20 ₆ is supplied to the heat exchanger 34, wherein heating the boiler water flowing through the flow path 20 _7, generating a high-pressure steam At the same time, after cooling itself, it is supplied to the _second carbon dioxide recovery device 312. Here, the carbon dioxide in the synthesis gas is recovered, and water that has been concurrently produced is discharged outside the system through the passage 20 _10. The recovered carbon dioxide, the and then through the passageway 20 ₈ compressor 32
Is sent to the first is boosted with the carbon dioxide recovered by the carbon dioxide recovery device 31 _1, the preliminary modified steam added natural flowing through the flow passage 20 within ₁₇ via the channel 20 ₅ A predetermined amount is added to the gas.

[0061] Synthesis gas carbon dioxide has been removed, the flow path 20 ₆ via by for example cobalt catalyst is fed to the Fischer-Tropsch (FT) reaction system 33 which is filled, wherein the hydrogen in the synthesis gas Reacts with carbon monoxide to synthesize gasoline, light oil and kerosene.

As described above, according to the third embodiment, the first
As in the embodiment, a synthesis gas having a molar ratio of H ₂ / CO of 1 to 2.5 can be produced, and this synthesis gas is, for example, Fischer-Tropsch (F) filled with a cobalt catalyst.
T) Gasoline, light oil and kerosene can be synthesized by supplying the reaction system 33 with hydrogen in the synthesis gas and reacting with carbon monoxide.

The pre-reformer 3 is located upstream of the reformer 10.
6 where natural gas mainly C2 like ethane
Or more hydrocarbons with C1 (methane) and CO, by pre-reforming in H _2, can reduce the thermal load at the reformer 10. As a result, the amount of fuel supplied to the combustion radiating section 12 of the reformer 10 can be reduced, so that synthesis gas can be produced with a small amount of fuel.

Example 3 In Example 3, the production of the synthesis gas of the third embodiment described above will be described more specifically with reference to a synthesis plant shown in FIG.

The fuel (natural gas) was supplied to the combustion radiator 12 of the reformer 10 under the condition of 544 kmol / hr, and was burned by the combustion radiator 12 together with air. Further, natural gas, steam supply (steam) to the raw gas-introducing passageway 20 ₁ under the conditions shown in Table 3, the carbon dioxide following Table 3 (recovered from the combustion exhaust gas and synthesis gas in the reformer 10)
Supplying the preliminary reformer 36 with the reformer 10 to the pre-reforming steam added natural gas flowing through the passage 20 ₁₇ connecting with the conditions shown in the reaction tube 11 of the reformer 10 to the natural gas To produce a synthesis gas by steam reforming. Table 3 shows the composition of the obtained synthesis gas.

The item (A) in Table 3 is used for introducing the raw material gas.
Channel 20₁Natural gas supplied to the country, item (B)
Flow path 20₁Steam (steam) supplied to
Item (C) is the fuel generated in the combustion radiating section 12 of the reformer 10.
First carbon dioxide capture device 31 from flue gas₁Collected by
Carbon dioxide, item (D) is the second
Carbon oxide recovery device 31_TwoCarbon dioxide, items recovered in
(E) connects the preliminary reformer 36 and the reformer 10.
Channel 20₁₇, Which is supplied to the compressor 32 by being boosted in pressure.
2 carbon dioxide capture device 31₁, 31_TwoDioxide recovered in
Carbon, item (F) is produced in the reformer 10 and heat exchanger 3
4 through the second carbon dioxide capture device 31 _TwoSupplied to
Item (G) is the second carbon dioxide capture device 3
1_TwoFrom the FT reaction system 33
And supplied to the second carbon dioxide capture device 31_TwoWith dioxide
Represents synthesis gas from which carbon has been removed. These sections
The eyes (A) to (H) are additionally shown in FIG.

[0067]

[Table 3]

[0068] The first carbon dioxide supply recovered in the second carbon dioxide recovery device 31 _1, 31 ₂ to the pre-reformed steam added natural gas as it is clear from Table 3, the modified these gases By supplying the fuel to the reaction tube 11 of the reformer 10, even if the fuel supply to the combustion radiating section 12 of the reformer 10 is reduced by about 20% compared to the first embodiment, H ₂ / It can be seen that a synthesis gas having a CO molar ratio of about 2 can be produced.

(Fourth Embodiment) FIG. 4 is a schematic diagram showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the fourth embodiment. In FIG. 4, the same members as those in FIG. 1 described above are denoted by the same reference numerals, and description thereof will be omitted.

[0070] The synthesis plant, the heat exchanger type humidifier synthesis gas flow passage 20 ₆ which is located between the carbon dioxide recovery device 31 ₂ and the heat exchanger 34 on the downstream side of the second reformer 10 37 Is interposed. Raw gas-introducing passageway 20 _1,
It is connected to the top of the humidifier 37. The humidifier 3
7, the reaction tube 11 of the reformer 10 through the channel 20 ₁₈
Is connected to the upper end. The flow path 20 ₁₈ is connected to the reaction tube 11 via the convection portion 13 of the reformer 10.

Next, a method for producing synthesis gas will be described with reference to the above-described synthesis plant shown in FIG.

First, the fuel for combustion is supplied to the combustion radiating section 12 of the reformer 10 in the same manner as in the first embodiment, and
1 is heated to a predetermined temperature, generated by the combustion radiation unit 12, to recover the carbon dioxide in the cooled combustion exhaust gas at the first carbon dioxide recovery device 31 ₁ is supplied to the compressor 32.

[0073] Natural gas containing methane as a main component is fed to the passage 20 _first source gas introduction. At this time, carbon dioxide has been pressurized by the compressor 32 is added a predetermined amount in the natural gas and then through the passageway 20 _5. Natural gas carbon dioxide is added (carbon dioxide added natural gas) flows through the said raw material gas introduction passage 20 ₁ is fed to the top of the humidifier 37. By feeding water through channels 20 ₁₉ on top of the humidifier 37 to humidify the carbon dioxide added natural gas. That is, the carbon dioxide addition the natural gas is in contact with water supplied from the flow path 20 ₁₉ by the humidifier 37, after being humidified, was fed through the channel 20 ₆ from the reaction tube 11 of the reformer 10 Heat is exchanged with the high-temperature synthesis gas, heated, and further humidified.

[0074] humidified carbon dioxide added natural gas is supplied to the reaction tube 11 of the reformer 10 through the channel 20 _18. In this case, water vapor (steam) is fed to the gas mixture flowing through the flow passage 20 within ₁₈ through the channel 20 _20, deficient amount of steam is supplied. The natural gas, steam and carbon dioxide mainly containing methane (CH ₄ ) supplied to the reaction tube 11 of the reformer 10 are mainly subjected to steam reforming in the presence of a catalyst in the reaction tube 11. And converted into a synthesis gas containing hydrogen, carbon monoxide and carbon dioxide according to the above formulas (1) and (2).

In the reforming reaction, when steam and carbon dioxide are added to the natural gas, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 is produced.

Since the reforming reaction is an endothermic reaction, as described above, the combustion radiating section 12 of the reformer 10 burns the fuel gas and the air so that the inside of the reaction tube 11 is, for example, 85 mm.
Heat to 0-900C.

[0077] The resulting synthesis gas, synthesis gas via the flow passage 20 ₆ is supplied to the heat exchanger 34, wherein heating the boiler water flowing through the flow path 20 _7, generating a high-pressure steam At the same time, after cooling itself, it is supplied to the humidifier 37 and used as a heat source for humidifying the carbon dioxide-added natural gas. The synthesis gas discharged from the humidifier 37 is supplied to the _second carbon dioxide recovery device 312. Here, the carbon dioxide in the synthesis gas is recovered, and water that has been concurrently produced is discharged outside the system through the passage 20 _10. The recovered carbon dioxide, the sent to compressor 32 and then through the passageway 20 _8, is boosted with the recovered carbon dioxide in the first carbon dioxide recovery device 31 _1, via the flow path 20 ₅ It is added a predetermined amount of natural gas flowing through the raw gas-introducing passageway 20 ₁ and.

[0078] Synthesis gas carbon dioxide has been removed, the flow path 20 ₆ via by for example cobalt catalyst is fed to the Fischer-Tropsch (FT) reaction system 33 which is filled, wherein the hydrogen in the synthesis gas Reacts with carbon monoxide to synthesize gasoline, light oil and kerosene.

As described above, according to the fourth embodiment, the first
As in the embodiment, a synthesis gas having a molar ratio of H ₂ / CO of 1 to 2.5 can be produced, and this synthesis gas is, for example, Fischer-Tropsch (F) filled with a cobalt catalyst.
T) Gasoline, light oil and kerosene can be synthesized by supplying the reaction system 33 with hydrogen in the synthesis gas and reacting with carbon monoxide.

[0080] Further, a humidifier 37 disposed downstream of the reformer 10, where by humidifying the carbon dioxide added natural gas, reduces the amount of steam supplied to the carbon dioxide adding natural gas through a flow path 20 ₂₀ it can. As a result, the amount of steam supplied to the reaction tube 11 of the reformer 10 together with the natural gas and the like can be reduced, so that synthesis gas can be produced at low cost.

Example 4 In Example 4, the production of the synthesis gas of the fourth embodiment described above will be described more specifically with reference to a synthesis plant shown in FIG.

The fuel (natural gas) was supplied to the combustion radiator 12 of the reformer 10 under the condition of 625 kmol / hr, and was burned by the combustion radiator 12 together with air. Further, natural gas, carbon dioxide is supplied to the humidifier 37 through the raw gas-introducing passageway 20 ₁ under the conditions shown in the following Table 4 (the reformer recovered from the combustion exhaust gas and synthesis gas 10), water vapor (steam) It was fed to the carbon dioxide addition the natural gas after the humidification flowing through the flow path 20 in ₁₈ under the conditions shown in table 4, the reaction tube 1 in this natural gas, reformer 10 steam and carbon dioxide
A synthesis gas was produced by steam reforming at 1.
Table 4 shows the composition of the obtained synthesis gas.

[0083] Incidentally, Table 4 items (A) is natural gas supplied to the raw gas-introducing passageway 20 _1, item (B) in the flow path 20 ₁₈ carbon dioxide added natural gas after the humidification is circulated The supplied steam (steam), item (C) is the reformer 10
The carbon dioxide recovered by the first carbon dioxide recovery device 31 ₁ from the combustion exhaust gas generated by the combustion radiating section 12 of the above, item (D) is the second carbon dioxide recovery device 31 from the synthesis gas.
The recovered carbon dioxide at _2, item (E) dioxide recovered in the first, second carbon dioxide recovery device 31 _1, 31 ₂ is supplied with pressurized by the compressor 32 to the passage 20 _first source gas introduction Carbon, item (F) is produced in the reformer 10 and heat exchanger 3
4 and the humidifier 37 through the synthesis gas fed to the second carbon dioxide recovery device 31 _2, water entry (G) is supplied to the humidifier, item (H) and the second carbon dioxide recovery device 3
1 ₂ water discharged from the item (I) is, FT reaction system 33
And the synthesis gas from which carbon dioxide has been removed by the _second carbon dioxide capture device 312. These items (A) to (I) are additionally shown in FIG.

[0084]

[Table 4]

As is clear from Table 4 above, natural gas
1. Second carbon dioxide capture device 31 ₁, 31_TwoCollected at
Carbon dioxide is supplied, and this mixed gas is passed through a humidifier 37.
Supply to the reaction tube 11 of the reformer 10
The amount of water vapor to be supplied is about 1 /
Reduce H by about 3_Two/ CO molar ratio of about 2
It can be seen that synthesis gas can be produced.

(Fifth Embodiment) FIG. 5 is a schematic view showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the fifth embodiment. In FIG. 5, the same members as those in FIG. 1 described above are denoted by the same reference numerals, and description thereof will be omitted.

[0087] The synthesis plant, the heat exchanger type humidifier synthesis gas flow passage 20 ₆ which is located between the carbon dioxide recovery device 31 ₂ and the heat exchanger 34 on the downstream side of the second reformer 10 37 Is interposed. Raw gas-introducing passageway 20 _1,
It is connected to the top of the humidifier 37. The humidifier 3
7 is connected to the top of the pre-reformer 36 located on an upstream side of the reformer 10 through the channel 20 _18. The pre-reformer 36 is connected to the upper end of the reaction tube 11 of the reformer 10 through the channel 20 _17. The flow path 20
Reference numeral ₁₇ is connected to the reaction tube 11 via a convection section 13 of the reformer 10. Compressor 32 is connected to the flow path 20 ₁₇ and then through the passageway 20 ₅ for connecting the reformer 10 and the preliminary reformer 36.

Next, a method for producing synthesis gas will be described with reference to the above-described synthesis plant shown in FIG.

[0089] Natural gas containing methane as a main component is fed to the top of the humidifier 37 through the raw gas-introducing passageway 20 _1. By feeding water through channels 20 ₁₉ on top of the humidifier 37 to humidify the natural gas. That is, the natural gas is in contact with water supplied from the flow path 20 ₁₉ by the humidifier 37, after being humidified, the synthesis of high temperature supplied through the flow passage 20 ₆ from the reaction tube 11 of the reformer 10 Heat is exchanged with the gas and heated, and further humidified.

[0090] humidified natural gas is supplied to the pre-reformer 36 through the channel 20 _18. In this case, water vapor (steam) is supplied to the natural gas flowing through the flow passage 20 within ₁₈ through the channel 20 _20, deficient amount of steam is supplied. Further, a humidified natural gas further steam is added, flows through the flow passage 20 in _18, is heated (preheated) while passing through the convection portion 13 of the reformer 10. Wherein the pre-reformer 36, methane and CO C2 or more hydrocarbons such as predominantly ethane in the natural gas C1, is reformed into H _2.

[0091] Preliminary modified steam added natural gas is supplied to the reaction tube 11 of the reformer 10 through the channel 20 _17. At this time, carbon dioxide has been pressurized by the compressor 32 is added a predetermined amount to the pre-reformed steam added natural gas flowing through the said channel 20 ₁₇ and then through the passageway 20 _5.
Methane (CH) supplied to the reaction tube 11 of the reformer 10
₄ ) Natural gas, steam and carbon dioxide, whose main components are methane, are mainly steam reformed in the presence of a catalyst in the reaction tube 11, and are converted into hydrogen, monoxide according to the above formulas (1) and (2). It is converted to synthesis gas containing carbon and carbon dioxide.

In the reforming reaction, when steam and carbon dioxide are added to the natural gas, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 or less is produced.

Since the reforming reaction is an endothermic reaction, as described above, the combustion radiating section 12 of the reformer 10 burns the fuel gas and the air so that the inside of the reaction tube 11 is, for example, 85%.
Heat to 0-900C.

[0094] The resulting synthesis gas, synthesis gas via the flow passage 20 ₆ is supplied to the heat exchanger 34, wherein heating the boiler water flowing through the flow path 20 _7, generating a high-pressure steam At the same time, after cooling itself, it is supplied to the humidifier 37 and used as a heat source for humidifying the natural gas. The synthesis gas discharged from the humidifier 37 is
It is supplied to the second carbon dioxide recovery device 31 _2. Here, the carbon dioxide in the synthesis gas is recovered, and water that has been concurrently produced is discharged outside the system through the passage 20 _10. The recovered carbon dioxide, the sent to compressor 32 and then through the passageway 20 _8, is boosted with the recovered carbon dioxide in the first carbon dioxide recovery device 31 _1, via the flow path 20 ₅ It is added a predetermined amount to the pre-reformed steam added natural gas flowing through the flow passage 20 within ₁₇ to.

[0095] Synthesis gas carbon dioxide has been removed, the flow path 20 ₆ via by for example cobalt catalyst is fed to the Fischer-Tropsch (FT) reaction system 33 which is filled, wherein the hydrogen in the synthesis gas Reacts with carbon monoxide to synthesize gasoline, light oil and kerosene.

As described above, according to the fifth embodiment, the first
As in the embodiment, a synthesis gas having a molar ratio of H ₂ / CO of 1 to 2.5 can be produced, and this synthesis gas is, for example, Fischer-Tropsch (F) filled with a cobalt catalyst.
T) Gasoline, light oil and kerosene can be synthesized by supplying the reaction system 33 with hydrogen in the synthesis gas and reacting with carbon monoxide.

Further, the pre-reformer 3 is provided upstream of the reformer 10.
6 where natural gas mainly C2 like ethane
Or more hydrocarbons with C1 (methane) and CO, by pre-reforming in H _2, can reduce the thermal load at the reformer 10. As a result, the amount of fuel supply to the combustion radiating section 12 of the reformer 10 can be reduced, so that synthesis gas can be produced at low cost.

Further, a humidifier 37 is provided downstream of the reformer 10.
The provided here by humidifying the natural gas, it can reduce the water vapor content supplied through the natural gas flow channel 20 _20. As a result, the amount of steam supplied to the reaction tube 11 of the reformer 10 together with the natural gas and the like can be reduced, so that synthesis gas can be produced at low cost.

In the third to fifth embodiments, the first and second carbon dioxide recovery devices are replaced by the second
As in the embodiment, the synthesis gas may be produced using the first and second carbon dioxide absorption towers containing the same carbon dioxide absorption liquid and one carbon dioxide recovery device.

(Sixth Embodiment) FIG. 6 is a schematic view showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the sixth embodiment.

The reformer 10 includes a steam reforming reaction tube 11.
And a combustion radiating section 12 arranged around the reaction tube 11.
And a chimney 14 connected to the combustion radiating section 12 via a convection section (waste heat recovery section) 13. The reaction tube 11 is filled with, for example, a nickel-based catalyst.

[0102] raw gas-introducing passageway 20 ₁ is connected to the upper end of the reaction tube 11 via the convection portion 13 of the reformer 10. In the passage 20 _1, it may be interposed desulfurizer (not shown). Steam (steam) introduction channel 2
0 ₂ is connected to the raw gas-introducing passageway 20 ₁ which is positioned on the upstream side of the convection portion 13. Flow path for fuel introduction 20 ₃
Is connected to the combustion radiating section 12 of the reformer 10.

The carbon dioxide recovery unit 31 is provided with the reformer 1
The convection section 13 is provided with a convection section 13 for collecting carbon dioxide in the combustion exhaust gas. The carbon dioxide recovery apparatus 31 is connected to a compressor 32 and then through the passageway 20 _4. The compressor 32, the raw gas-introducing passageway 20 ₁ which is upstream of the reformer 10 and then through the passageway 20 ₅
It is connected to the.

[0104] The synthesis gas flow passage 20 _6, one end connected to the reaction tube 11 the lower end of the reformer 10, the other end for example Fischer cobalt-based catalyst is filled-Tropsch (FT) reaction system 33 It is connected. The FT reaction system 33 is connected to the raw gas-introducing passageway 20 ₁ which is upstream of the reformer 10 via the purge passage 20 ₂₁ for supplying purge gas. The catalyst filled in the FT reaction system 33 is not limited to a cobalt catalyst, and for example, an iron catalyst can be used. The heat exchanger 34 is interposed in said synthesis gas flow passage 20 _6. The heat exchanger 34 has a passage 20 ₇ is crossed, for generating a high-pressure steam (steam) is heated, for example, boiler water flowing through the flow path 20 _7. Incidentally, for example, the convection section 13 of the passage 20 ₉ boiler water is circulated in the reformer 10
The exhaust gas of the convection section 13 and the boiler water intersect with each other to exchange heat, thereby cooling the exhaust gas and heating the boiler water itself to generate high-pressure steam (steam).

Next, a method for producing a synthesis gas will be described with reference to the synthesis plant shown in FIG.

[0106] First, combustion fuel is a fuel introducing passage 20 ₃
Is supplied to the combustion radiator 12 of the reformer 10, where it is combusted with air to heat the reaction tube 11 to a predetermined temperature. The combustion exhaust gas containing carbon dioxide generated in the combustion radiating section 12 reaches the chimney 14 via the convection section 13. The combustion exhaust gas is natural gas, and the flow passage 20 ₉ within is boiler water heat exchanger for circulating the cooling flowing through the raw gas-introducing passageway 20 ₁ while passing through the convection portion 13. Carbon dioxide cooled combustion exhaust gas is recovered by the carbon dioxide recovery apparatus 31, it is supplied to the compressor 32 and then through the passageway 20 _4. The cooled combustion exhaust gas from which carbon dioxide has been removed is discharged from the chimney 14 to the atmosphere.

Natural gas containing methane as a main component is a raw material gas.
Flow path 20₁Supplied to At this time, the compressor
The carbon dioxide pressurized at 32_FiveVia via
A predetermined amount is added to the natural gas. In addition, steam (stee
Is a flow path 20 for introducing steam. _TwoThrough the natural gas
A predetermined amount is added. This steam is passed through the heat exchanger 34.
Produced by heat exchange of boiler water with synthesis gas
The steam and boiler water are combusted in the convection section 13 of the reformer 10.
The steam generated by heat exchange with the flue gas is
Used.

[0108] Natural gas carbon dioxide and water vapor is added, the raw material gas flows through the introduction passage 20 ₁ is heated while passing through the convection portion 13 of the reformer 10 (preheating) Thereafter, it is supplied to the reaction tube 11. The natural gas, steam and carbon dioxide mainly containing methane (CH ₄ ) supplied to the reaction tube 11 of the reformer 10 are mainly subjected to steam reforming in the presence of a catalyst in the reaction tube 11. And converted into a synthesis gas containing hydrogen, carbon monoxide and carbon dioxide according to the above formulas (1) and (2).

In the reforming reaction, when steam and carbon dioxide are added to the natural gas, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 is produced.

Since the reforming reaction is an endothermic reaction, the fuel gas and the air are burned by the combustion radiating section 12 of the reformer 10 as described above, so that the inside of the reaction tube 11 is, for example, 85 mm.
Heat to 0-900C.

The obtained synthesis gas is supplied to a flow path for syngas distribution.
20₆Is supplied to the heat exchanger 34 via the
20₇Boiler water flowing through the furnace to generate high-pressure steam
After being cooled down,
Fisher-Tropsch (F
T) is supplied to the reaction system 33, where the water in the synthesis gas is
Reacts with carbon monoxide to produce gasoline, light oil and kerosene.
Synthesized. In this synthesis reaction, carbon dioxide and
And purge gas containing unreacted natural gas
You. The purge gas is supplied to the flow path 20_{twenty one}Via the raw material
Gas introduction channel 20 ₁Natural gas in the area as a source of carbon dioxide
Is added.

[0112] above, when performing the reforming reaction is supplied to the reaction tube 11 of the reformer 10 natural gas steam is added through passage 20 _first source gas introduction according to the sixth embodiment, the modified A combustion radiator 12 is provided for the purpose of heating the reaction tube 11 of the reformer 10 because the heat reaction is an endothermic reaction. The combustion exhaust gas discharged from the combustion radiator 12 is cooled, and carbon dioxide was recovered by carbon dioxide recovery apparatus 31, after pressurized by the compressor 32, and then through the passageway 20 ₅ flowing through the raw gas-introducing passageway 20 ₁ which is upstream of the reformer 10 Supply and add to natural gas. Moreover, it added to natural gas Fischer-Tropsch reaction system 33 the raw gas-introducing passageway 20 ₁ and then through the passageway 20 ₂₁ to a purge gas containing carbon dioxide generated in. By supplying carbon dioxide to the steam-added natural gas in this way, a synthesis gas having a H ₂ / CO molar ratio of 1 to 2.5 can be produced. The synthesis gas having such a molar ratio of H ₂ / CO is supplied to, for example, a Fischer-Tropsch (FT) reaction system 33 filled with a cobalt catalyst to react hydrogen in the synthesis gas with carbon monoxide. Can synthesize gasoline, light oil and kerosene.

[0113] Thus, to procure carbon dioxide inside the production plant of synthesis gas containing Fischer-Tropsch reaction system (the reformer), i.e. it is possible to procure carbon dioxide on their own, CO _2, such as ammonia plant The source is not confined to the location adjacent to it, and the synthesis gas having a molar ratio of H ₂ / CO suitable for synthesizing gasoline, gas oil and kerosene in the Fischer-Tropsch reaction system can be produced at low cost anywhere. .

In addition, the Fischer-Tropsch reaction system 33
A carbon dioxide capture device for recovering carbon dioxide in synthesis gas as in the first to fifth embodiments described above by supplying and adding a purge gas containing carbon dioxide generated in the above process to a natural gas as a carbon dioxide source Since it is not necessary to separately provide a gas, it is possible to produce the above-mentioned synthesis gas and synthesize gasoline, light oil and kerosene in an inexpensive plant.

Example 5 In Example 5, the production of the synthesis gas of the sixth embodiment described above will be described more specifically with reference to a synthesis plant shown in FIG.

The fuel (natural gas) was supplied to the combustion radiator 12 of the reformer 10 under the condition of 625 kmol / hr, and was burned by the combustion radiator 12 together with air. In addition, natural gas, steam (steam) and carbon dioxide (carbon dioxide recovered from the combustion exhaust gas of the reformer 10 and purge gas generated in the Fischer-Tropsch reaction system 33) were introduced under the conditions shown in Table 5 below to feed raw material gas. It is supplied to the channels 20 ₁ to produce a synthesis gas by steam reforming in the reaction tube 11 of the reformer 10. Table 5 shows the composition of the obtained synthesis gas.

[0117] Incidentally, Table 5 Item (A) is natural gas supplied to the passage 20 _first source gas introduction, item (B) is water vapor supplied to the passage 20 _first source gas introduction (steam),
Item (C) carbon dioxide recovered by the carbon dioxide recovery apparatus 31 which is supplied with pressurized by the compressor 32 to the raw gas-introducing passageway 20 _1, items (D) is a purge gas generated in the Fischer-Tropsch reaction system 33 , Item (E) is the reformer 10
, And supplied to the Fischer-Tropsch reaction system 33 through the heat exchanger 34. In addition,
These items (A) to (E) are additionally shown in FIG.

[0118]

[Table 5]

As is clear from Table 5, the carbon dioxide recovered by the carbon dioxide recovery unit 31 is supplied to the natural gas to which the steam has been added, and the purge gas containing the carbon dioxide generated in the Fischer-Tropsch reaction system 33 is supplied. And
It is understood that by supplying these gases to the reaction tube 11 of the reformer 10, a synthesis gas having a H ₂ / CO molar ratio of about 2 can be produced.

(Seventh Embodiment) FIG. 7 is a schematic diagram showing a main part of a gasoline, light oil and kerosene synthesis plant used for producing a synthesis gas according to the seventh embodiment. In FIG. 7, the same members as those in FIG. 6 described above are denoted by the same reference numerals, and description thereof will be omitted.

[0121] The synthesis plant, the heat exchanger type humidifier 37 to the flow passage 20 ₆ which is located between the downstream side of the heat exchanger 34 and the Fischer-Tropsch reaction system 33 of the reformer 10 is interposed. Raw gas-introducing passageway 20 _1, the humidifier 3
7 is connected to the top. The humidifier 37 is provided in the channel 2
0 ₁₈ is connected to the top of the pre-reformer 36 located upstream of the reformer 10. This pre-reformer 36
It is connected through the channel 20 ₁₇ to the upper end of the reaction tube 11 of the reformer 10. The flow path 20 ₁₇ is connected to the reaction tube 11 via the convection portion 13 of the reformer 10. Compressor 32, the flow path 20 and then through the passageway 20 ₅ for connecting the reformer 10 and the preliminary reformer 36
Connected to ₁₇ . FT reaction system 33 is connected to the flow path 20 _21, wherein the raw gas-introducing passageway 20 ₁ through the for supplying a purge gas.

Next, a method for producing synthesis gas will be described with reference to the above-described synthesis plant shown in FIG.

First, the combustion fuel is supplied to the combustion radiating section 12 of the reformer 10 and the reaction
1 is heated to a predetermined temperature, carbon dioxide generated in the combustion radiating section 12 and contained in the cooled combustion exhaust gas is recovered by a carbon dioxide recovery device 31 and supplied to a compressor 32.

[0124] Natural gas containing methane as a main component is fed to the top of the humidifier 37 through the raw gas-introducing passageway 20 _1. By feeding water through channels 20 ₁₉ on top of the humidifier 37 to humidify the natural gas. That is, the natural gas is in contact with water supplied from the flow path 20 ₁₉ by the humidifier 37, after being humidified, the synthesis of high temperature supplied through the flow passage 20 ₆ from the reaction tube 11 of the reformer 10 Heat is exchanged with the gas and heated, and further humidified.

[0125] humidified natural gas is supplied to the pre-reformer 36 through the channel 20 _18. In this case, water vapor (steam) is supplied to the natural gas flowing through the flow passage 20 within ₁₈ through the channel 20 _20, deficient amount of steam is supplied. Further, a humidified natural gas further steam is added, flows through the flow passage 20 in _18, is heated (preheated) while passing through the convection portion 13 of the reformer 10. In the pre-reformer 36, hydrocarbons mainly containing C2 or more such as ethane in natural gas and C2 in a purge gas supplied from a Fischer-Tropsch reaction system 33 described later.
More hydrocarbons is C1 methane and CO, is reformed into H _2.

[0126] Preliminary modified steam added natural gas is supplied to the reaction tube 11 of the reformer 10 through the channel 20 _17. At this time, carbon dioxide has been pressurized by the compressor 32 is added a predetermined amount to the pre-reformed steam added natural gas flowing through the said channel 20 ₁₇ and then through the passageway 20 _5.
Methane (CH) supplied to the reaction tube 11 of the reformer 10
₄ ) Natural gas, steam and carbon dioxide, whose main components are methane, are mainly steam reformed in the presence of a catalyst in the reaction tube 11, and are converted into hydrogen, monoxide according to the above formulas (1) and (2). It is converted to synthesis gas containing carbon and carbon dioxide.

When steam and carbon dioxide are added to the natural gas in the reforming reaction, methane (CH ₄ ): steam (H ₂ O) in the natural gas = 1: 1.
5 to 1: 3, methane (CH _4): carbon dioxide (CO ₂₎ =
By setting the ratio to 1: 1 to 1: 3, the molar ratio of H ₂
A synthesis gas having a composition of / CO of 1 to 2.5 is produced.

Since the reforming reaction is an endothermic reaction, as described above, the combustion radiator 12 of the reformer 10 burns the fuel gas and the air to cause the inside of the reaction tube 11 to reach, for example, 85%.
Heat to 0-900C.

The obtained synthesis gas is supplied to a synthesis gas flow path.
20₆Is supplied to the heat exchanger 34 via the
20₇Boiler water flowing through the furnace to generate high-pressure steam
Humidification after cooling itself
A heat source for humidifying the natural gas supplied to the
To be used. Syngas discharged from humidifier 37
Is, for example, a Fisher Toro filled with a cobalt catalyst.
Push (FT) reaction system 33, where the synthesis
Hydrogen in the gas reacts with carbon monoxide to produce gasoline, light oil,
And kerosene are synthesized. Also, in this synthesis reaction,
Purge gas containing carbon oxide and unreacted natural gas
Occurs. The purge gas is supplied to the flow path 20 _{twenty one}Via
The source gas introduction passage 20₁Carbon dioxide in natural gas inside
It is added as a source. In addition, C2 or more in the purge gas
Hydrocarbons are converted to C1 methane and C
O, H_TwoIt is reformed to.

As described above, according to the seventh embodiment, the sixth embodiment
As in the embodiment, a synthesis gas having a molar ratio of H ₂ / CO of 1 to 2.5 can be produced, and this synthesis gas is, for example, Fischer-Tropsch (F) filled with a cobalt catalyst.
T) Gasoline, light oil and kerosene can be synthesized by supplying the reaction system 33 with hydrogen in the synthesis gas and reacting with carbon monoxide.

Further, the Fischer-Tropsch reaction system 33
A carbon dioxide capture device for recovering carbon dioxide in synthesis gas as in the first to fifth embodiments described above by supplying and adding a purge gas containing carbon dioxide generated in the above process to a natural gas as a carbon dioxide source Since it is not necessary to separately provide a gas, it is possible to produce the above-mentioned synthesis gas and synthesize gasoline, light oil and kerosene in an inexpensive plant.

Further, a pre-reformer 36 is provided on the upstream side of the reformer 10, where C2 or more hydrocarbons such as ethane in natural gas and purge gas are converted into C1 (methane) or C1.
By reforming to O and H ₂ in advance, the heat load on the reformer 10 can be reduced. As a result, the amount of fuel supplied to the combustion radiating section 12 of the reformer 10 can be reduced, so that synthesis gas can be produced with a small amount of fuel.

Further, a humidifier 37 is provided downstream of the reformer 10.
The provided here by humidifying the natural gas, it can reduce the amount of steam supplied to the natural gas through the flow path 20 _20. As a result, the amount of steam supplied to the reaction tube 11 of the reformer 10 together with the natural gas and the like can be reduced, so that synthesis gas can be produced at low cost.

In the seventh embodiment, the humidifier is used.
Alternatively, the pre-reformer may be omitted. In the former case (humidifier
Is omitted) is a flow path 2 for introducing raw gas through which natural gas flows.
0₁To supply natural gas to which steam has been added.
The source gas introduction passage 20 ₁Through the pre-reformer 36
Supply directly to In the latter case (omitting the pre-reformer),
Source gas introduction passage 20 through which natural gas flows₁To dioxide
Diacid recovered by the carbon recovery unit 31 and pressurized by the compressor 32
Supply of carbonized gas and natural gas to which carbon dioxide has been added.
Source gas introduction channel 20₁To humidifier 37 through
And humidify. However, either method
Par containing carbon dioxide generated in the Tropsch reaction system 33
The raw material gas through which natural gas flows using digas as a carbon dioxide source
Flow path 20₁To supply.

[0135]

As described in detail above, according to the present invention, by procuring CO ₂ in a synthesis gas production plant including a Fischer-Tropsch reaction system, a CO ₂ source such as an ammonia plant is adjacent to the plant. Gasoline and gas oil which can be produced at low cost and can produce a synthesis gas having a H ₂ / CO molar ratio suitable for synthesizing gasoline, gas oil and kerosene in a Fischer-Tropsch reaction system regardless of the location. And a method for producing a synthesis gas for kerosene.

[Brief description of the drawings]

FIG. 1 shows gasoline used in a first embodiment of the present invention;
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

FIG. 2 shows gasoline used in a second embodiment of the present invention;
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

FIG. 3 shows gasoline used in a fourth embodiment of the present invention,
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

FIG. 4 shows gasoline used in a fourth embodiment of the present invention,
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

FIG. 5 shows gasoline used in a fifth embodiment of the present invention,
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

FIG. 6 shows gasoline used in a sixth embodiment of the present invention,
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

FIG. 7 shows gasoline used in the seventh embodiment of the present invention,
The schematic diagram which shows the principal part of the synthesis gas production in the synthesis plant of gas oil and kerosene.

[Explanation of symbols]

10 ... reformer 11 ... reaction tube, 12 ... combustion radiation unit, 13 ... convection section, 20 ₁ ... raw gas introducing passage, 20 ₃ ... fuel introducing passage, 20 ₂₁ ... purge passage, 31 , 31 ₁ , 31 ₂ ... carbon dioxide recovery unit, 31 ₃ ... absorption liquid regeneration unit, 33 ... Fischer-Tropsch (FT) reaction system, 35 ₁ , 35 ₂ ... carbon dioxide absorption tower, 36 ... pre-reformer 37 ... humidifier.

Claims (6)

[Claims] In producing a synthesis gas containing CO and H ₂ used for synthesizing gasoline, light oil and kerosene in a Fischer-Tropsch reaction system, a natural gas with steam is supplied to a reformer. At the same time, carbon dioxide is recovered from the combustion exhaust gas generated in the combustion radiating section for heating the reformer, and this carbon dioxide is supplied to the upstream side of the reformer, so that CO and H
_{2. A} method for producing a synthesis gas for gasoline, gas oil and kerosene, comprising producing a synthesis gas containing _{2 and} having a molar ratio of H ₂ / CO of 1 to 2.5. 2. The synthesis gas for gasoline, gas oil and kerosene according to claim 1, wherein carbon dioxide in the synthesis gas produced by said reformer is recovered and circulated upstream of said reformer. Manufacturing method. 3. A process for recovering carbon dioxide from flue gas discharged from the reformer and a process for recovering carbon dioxide in the synthesis gas using the same absorption liquid. Item 4. The method for producing gasoline, light oil and synthesis gas for kerosene according to Item 2. 4. When synthesizing the synthesis gas produced in the reformer to synthesize gasoline, light oil and kerosene in a Fischer-Tropsch reaction system, purge gas containing carbon dioxide generated in the reaction system is supplied to the reformer. The method for producing gasoline, light oil and kerosene syngas according to claim 1, wherein the gas is circulated upstream. 5. A pre-reformer is disposed upstream of the reformer, and the natural gas to which steam has been added is supplied to the reformer via the pre-reformer, The production of gasoline, gas oil and kerosene synthesis gas according to any one of claims 1 to 4, wherein carbon dioxide recovered from combustion exhaust gas is supplied to a flow path between the reformer and the pre-reformer. Method. 6. The step of adding steam to the natural gas includes arranging a humidifier downstream of the reformer, introducing synthesis gas from the reformer into the humidifier, and humidifying the waste gas with waste heat. The method according to any one of claims 1 to 5, wherein heating the vessel and supplying the natural gas and water to the heated humidifier, wherein steam is added to the natural gas. A method for producing syngas for gasoline, light oil and kerosene.