JP2019048743A - Modification method of hydrocarbon-containing gas, modification system of hydrocarbon-containing gas, manufacturing method of organic oxide and manufacturing system of organic oxide - Google Patents

Abstract

To enhance productivity of organic oxide further.SOLUTION: A synthesis device 30 for manufacturing a production gas containing organic oxide, hydrogen and hydrocarbon by contacting a mixed gas containing hydrogen and carbon monoxide with a synthesis catalyst, an oxide separation device 40 for separating the organic oxide from the production gas to manufacture a residue as a hydrocarbon-containing gas containing hydrogen and hydrocarbon, a hydrogen separation device 50 for separating hydrogen from the hydrocarbon-containing gas to manufacture a first separated gas containing the hydrogen and a second separated gas containing the hydrocarbon, a first modification device 70 for modifying the second separated gas to manufacture a carbon dioxide-containing gas containing carbon dioxide, a second modification device 80 for modifying the carbon dioxide-containing gas to manufacture a modified gas containing the hydrogen and the carbon monoxide, and a piping 82 for supplying the modified gas to the synthesis device 30 are included.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for reforming a hydrocarbon-containing gas, a system for reforming a hydrocarbon-containing gas, a method for producing an organic oxygenate, and a system for producing an organic oxygenate.

In recent years, there is a technology for producing an organic oxygenated product such as ethanol from cellulosic biomass such as woody biomass such as waste wood and herbaceous biomass such as rice straw.
As a technology for producing organic oxygenates from biomass, there is a method of converting biomass into a mixed gas containing hydrogen and carbon monoxide, contacting the mixed gas with a catalyst to synthesize organic oxygenates. As a method of converting biomass into mixed gas, there is a method of using a gasifier. However, if the composition of the obtained mixed gas is inadequate, unreacted raw materials remain and many byproducts are produced.

  In order to address these problems, Patent Document 1 separates unreacted raw materials (hydrogen, carbon monoxide) and hydrocarbons (methane, ethane, etc.) after the ethanol synthesis step, reforms the separated gas and reforms the hydrogen and carbon monoxide. The invention discloses that the reformed gas is recycled to the ethanol synthesis step. The invention of Patent Document 1 improves the productivity of ethanol by reforming hydrocarbons into hydrogen and carbon monoxide and using them as a raw material.

JP, 2012-149089, A

The gas separated after the ethanol synthesis step may contain 20 to 40 mol% of hydrocarbons. For this reason, it is necessary to use hydrocarbons effectively to further increase the productivity of organic oxygenates such as ethanol. Conventionally, there is a method of using a catalyst as a method of reforming hydrocarbons to hydrogen and carbon monoxide.
However, in the reforming method using a catalyst, the conversion efficiency of hydrocarbons was low. In addition, in the presence of high concentrations of carbon monoxide, the performance of the catalyst is reduced prematurely. For this reason, the prior art has not been able to improve the conversion efficiency of hydrocarbons to hydrogen and carbon monoxide.
Furthermore, when reforming hydrocarbons, high temperature steam is added, and reforming is performed at a temperature condition of 750 ° C. or higher. For this reason, the prior art requires a great deal of heat energy.
Then, an object of the present invention is to further improve the productivity of organic oxygenates.

As a result of intensive studies, the present inventors obtained the following findings.
Attempts to synthesize hydrogen and carbon monoxide from hydrocarbons and steam in the presence of hydrogen and carbon monoxide do not increase the conversion efficiency. This is because the synthesis reaction from hydrocarbon and steam to hydrogen and carbon monoxide is reversible.
Hydrocarbons can be efficiently converted to carbon monoxide by synthesizing carbon dioxide from hydrocarbons and oxygen at a low hydrogen concentration and then synthesizing carbon monoxide from carbon dioxide and hydrocarbons.
The present invention has been completed based on the above findings.

The present invention has the following aspects.
[1] Hydrogen is separated from a hydrocarbon-containing gas containing hydrogen and hydrocarbons to form a first separated gas containing hydrogen and a second separated gas containing hydrocarbons, and the second separated gas is reformed And a carbon dioxide-containing gas containing carbon dioxide, and reforming the carbon dioxide-containing gas to obtain a reformed gas containing hydrogen and carbon monoxide.
[2] A mixed gas containing hydrogen and carbon monoxide is brought into contact with a synthesis catalyst to form a product gas containing an organic oxygenate, hydrogen and a hydrocarbon, the organic oxygenate is separated from the product gas, and the balance is hydrogen And a hydrocarbon-containing gas containing hydrocarbon, hydrogen is separated from the hydrocarbon-containing gas, and a first separated gas containing hydrogen and a second separated gas containing hydrocarbon, the second separated gas Is reformed into a carbon dioxide-containing gas containing carbon dioxide, and the carbon dioxide-containing gas is reformed into a reformed gas containing hydrogen and carbon monoxide, and the reformed gas is brought into contact with the synthesis catalyst , Methods of producing organic oxygenates.
[3] The organic oxygen according to [2], wherein a portion of hydrocarbon is separated from the second separated gas, and the separated hydrocarbon and the carbon dioxide-containing gas are reformed to be the reformed gas Manufacturing method of
[4] The organic oxygenate according to [2] or [3], wherein carbon dioxide is separated from the mixed gas, and the separated carbon dioxide is reformed together with the carbon dioxide-containing gas to obtain the reformed gas. Production method.
[5] The method for producing an organic oxygenate according to any one of [2] to [4], wherein the first separated gas is brought into contact with the synthesis catalyst.

[6] A first separation device for separating hydrogen from a hydrocarbon-containing gas containing hydrogen and hydrocarbon to obtain a first separated gas containing hydrogen and a second separated gas containing hydrocarbon, (B) reforming the separated gas into a carbon dioxide-containing gas containing carbon dioxide, and reforming the carbon dioxide-containing gas into a reformed gas containing hydrogen and carbon monoxide And a second reformer for reforming a hydrocarbon-containing gas.
[7] A synthesis apparatus for contacting a mixed gas containing hydrogen and carbon monoxide with a synthesis catalyst to form a product gas containing organic oxygenate, hydrogen and hydrocarbon, and separating the organic oxygenate from the product gas An oxygenate separation device using hydrogen and a hydrocarbon containing gas containing hydrocarbon, hydrogen separated from the hydrocarbon containing gas, a first separated gas containing hydrogen, and a second containing hydrocarbon A hydrogen separation device serving as a separated gas, a first reforming device serving as a carbon dioxide-containing gas by reforming the second separated gas, and a carbon dioxide-containing gas; A system for producing an organic oxygenate, comprising: a second reformer configured to be a reformed gas containing hydrogen and carbon monoxide; and a pipe for supplying the reformed gas to the synthesis apparatus.
[8] A hydrocarbon separation apparatus for separating a part of hydrocarbons from the second separated gas, and a pipe for supplying separated hydrocarbons and the carbon dioxide-containing gas to the first reforming apparatus. The manufacturing system of the organic oxygenate as described in [7].
[9] The organic oxygen according to [7] or [8], comprising: a carbon dioxide separator for separating carbon dioxide from the mixed gas; and a pipe for supplying the separated carbon dioxide to the second reformer. Manufacturing system.
[10] The system for producing an organic oxygenate according to any one of [7] to [9], including a pipe for supplying the first separated gas to the synthesis apparatus.

In the present invention, "organic oxygenate" is a molecule consisting of carbon atom, hydrogen atom and oxygen atom, such as acetic acid, ethanol, acetaldehyde, methanol, propanol, methyl formate, ethyl formate, methyl acetate, ethyl acetate and the like.
As used herein, “CO conversion” is “the percentage of the number of moles of CO in the mixed gas that is occupied by the number of moles of CO consumed”.

  According to the method for producing an organic oxygenate of the present invention, the productivity of the organic oxygenate can be further enhanced.

It is a schematic diagram which shows the manufacturing system of the organic oxide which concerns on one Embodiment of this invention. It is a schematic diagram which shows the manufacturing system of the organic oxide of the comparative example 1. FIG.

The system for reforming a hydrocarbon-containing gas of the present invention (hereinafter sometimes simply referred to as "reforming system") comprises a hydrogen separator, a first reformer, and a second reformer.
The organic oxide production system of the present invention (hereinafter sometimes referred to simply as “production system”) comprises contacting a mixed gas containing hydrogen and carbon monoxide with a synthesis catalyst to produce organic oxygenates, hydrogen and hydrocarbons. A synthesis apparatus is used as a product gas to be contained, and a first separation apparatus.
Hereinafter, a reforming system and a manufacturing system according to an embodiment of the present invention will be described with reference to the drawings.

The manufacturing system 1 of FIG. 1 includes a reforming system 2.
The manufacturing system 1 includes a gasifier 10, a carbon dioxide separator 20, a synthesizer 30, an oxygenate separator 40, a hydrogen separator 50, a hydrocarbon separator 60, and a first reformer 70. And a second reformer 80. In addition, the manufacturing system 1 includes an oxygenate storage device 45 and an oxygen supply source 75.
The manufacturing system 1 includes the piping 12, the piping 22, the piping 24, the piping 32, the piping 42, the piping 44, the piping 52, the piping 54, the piping 62, the piping 64, the piping 72, the piping 74, and the piping 82.
The pipe 12 connects the gasifier 10 and the carbon dioxide separator 20. The pipe 22 connects the carbon dioxide separator 20 and the synthesizer 30. The pipe 24 connects the carbon dioxide separator 20 and the second reformer 80. The pipe 32 connects the synthesizing device 30 and the oxygenate separating device 40. The pipe 42 connects the oxygenate separation device 40 and the hydrogen separation device 50. The pipe 44 connects the oxygenate separation device 40 and the oxygenate storage device 45. The pipe 52 connects the hydrogen separator 50 and the hydrocarbon separator 60. The pipe 54 connects the hydrogen separator 50 and the synthesizer 30. The pipe 62 connects the hydrocarbon separator 60 and the first reformer 70. The pipe 64 connects the hydrocarbon separator 60 and the second reformer 80. The pipe 72 connects the first reformer 70 and the second reformer 80. The pipe 74 connects the first reformer 70 and the oxygen supply source 75. The pipe 82 connects the second reformer 80 and the synthesizer 30.
In the present embodiment, the reforming system 2 includes a hydrogen separation device 50, a pipe 52, a hydrocarbon separation device 60, a pipe 62, a pipe 64, a first reformer 70, a pipe 72, a pipe 74, an oxygen source 75, and a second reformer 80.

  The gasifier 10 is a device that generates a mixed gas containing hydrogen and carbon monoxide. The gasifier 10 is, for example, a gasifier that uses general waste, industrial waste and the like as fuel.

  The carbon dioxide separation apparatus 20 is a separator (membrane type separator) equipped with a carbon dioxide separation membrane, a pressure fluctuation adsorption gas separator (PSA), a temperature fluctuation adsorption gas separator (TSA), an amine adsorption type removal apparatus, etc. . Among them, the membrane separator is preferred. The amine adsorption type removal apparatus is, for example, a scrubber which dissolves carbon dioxide in an amine aqueous solution.

The synthesis device 30 is a device for bringing a mixed gas into contact with a synthesis catalyst to obtain a product gas containing an organic oxygenate.
The synthesis apparatus 30 is, for example, a reaction tower having a reaction bed of synthesis catalyst. The reaction bed may be a fixed bed or a fluidized bed.
The synthesis catalyst may be any catalyst that can synthesize organic oxygenates from a mixed gas. The synthesis catalyst is a metal catalyst containing, for example, one or more platinum group elements selected from ruthenium, rhodium, palladium, osmium, iridium and platinum.

  From the viewpoint of further increasing the CO conversion, the synthesis catalyst may contain a metal other than a platinum group element (optional catalyst metal). The optional catalyst metal is, for example, a hydrogenation active metal or co-active metal.

The hydrogenation active metal is, for example, one or more elements selected from alkali metals and elements belonging to Groups 6 to 10 of the periodic table.
The alkali metal is, for example, lithium or sodium. The element which belongs to 6th group is chromium and molybdenum, for example. The elements belonging to Group 7 of the periodic table are, for example, manganese and rhenium. An element belonging to Group 8 of the periodic table is, for example, ruthenium. An element belonging to Group 9 of the periodic table (except for platinum group elements) is, for example, cobalt. An element belonging to Group 10 of the periodic table (except for platinum group elements) is, for example, nickel.
These hydrogenation active metals may be used alone or in combination of two or more. Also, some or all of these hydrogenation activation metals may be oxides or sulfides.

  The auxiliary metal is, for example, one or more selected from titanium, vanadium, chromium, boron, magnesium, a lanthanoid and an element belonging to Group 13 of the periodic table. Among them, titanium, magnesium and vanadium are preferable as the auxiliary metal, and titanium is more preferable.

The synthesis catalyst may have a metal-supported carrier. The type of support is not particularly limited, and supports used in conventional catalysts can be applied. As a carrier, a porous carrier is preferred.
The material of the porous carrier is, for example, silica, zirconia, titania, magnesia, alumina, zeolite or the like. As the porous carrier, silica is preferred. In the market, various silicas having different specific surface areas and pore diameters are available.
The preferred size of the porous carrier is, for example, a particle size of 0.5 to 5000 μm.
The suitable total pore volume of the porous carrier is, for example, 0.01 to 1.0 mL / g.
A suitable average pore diameter of the porous carrier is, for example, 0.01 to 20 nm.
The suitable specific surface area of the porous carrier is, for example, 1 to 1000 m ² / g.

The supported amount of the platinum group element with respect to 100 parts by mass of the carrier is, for example, 0.5 to 10 parts by mass.
The supported amount of the hydrogenation active metal is, for example, 1 to 10 parts by mass with respect to 100 parts by mass of the porous support in total of the platinum group element and the hydrogenation active metal.
The suitable loading amount of the auxiliary metal is, for example, 0.01 to 20 parts by mass with respect to 100 parts by mass of the carrier.

An example of a preferable synthesis catalyst is represented by the following formula (I), and contains (A) component: rhodium, (B) component: manganese, (C) component: alkali metal, and (D) component: titanium It is a catalyst. This catalyst is a catalyst in which the components (A) to (C) are supported on the primary support after the support (D) is supported on a carrier to form a primary support.
aA, bB, cC, dD ... (I)
[Wherein A represents component (A), B represents component (B), C represents component (C), D represents component (D), a, b, c and d Represents a mole fraction, a + b + c + d = 1, a = 0.05 to 0.98, b = 0.0005 to 0.67, c = 0.0005 to 0.51, d = 0.002 to 0.95 It is. ]

The oxygenate separation device 40 is a device for separating an organic oxygenate from a product gas to obtain a hydrocarbon-containing gas.
The oxygenate separation device 40 is, for example, a cooler, a heat exchanger, a condenser, a gas-liquid separation device such as demister, an adsorption device having activated carbon, a distillation device, or a combination thereof. As the oxygenate separation device 40, a device that can separate organic oxygenates as much as possible is preferable. Therefore, as the oxygenate separation device 40, a combination of two or more kinds of gas-liquid separation devices, and a combination of two or more kinds of gas-liquid separation devices and an adsorption device are preferable. As the oxygenate separation device 40, for example, a combination of a heat exchanger and a demister, or a combination of a heat exchanger, a demister and an adsorption device is preferable.

The oxygenate storage device 45 is a device for storing the organic oxygenate separated by the oxygenate separation device 40.
The oxygenate storage device 45 is, for example, a pressure container such as a cylinder, a storage tank, or the like.

The hydrogen separation device 50 is a device that separates hydrogen from a hydrocarbon-containing gas into a first separated gas containing hydrogen and a second separated gas containing hydrocarbons.
The hydrogen separation device 50 is, for example, a membrane separation device equipped with a hydrogen separation membrane, a gas-liquid separation device, PSA, TSA or the like.

The hydrocarbon separation device 60 is a device that separates part of hydrocarbons from the second separated gas.
The hydrocarbon separation device 60 is, for example, a gas-liquid separation device, an activated carbon adsorption tank, PSA, or TSA.

The first reformer 70 is an apparatus that reforms the second separated gas into a carbon dioxide-containing gas containing carbon dioxide.
The first reformer 70 is, for example, a combustion furnace. The combustion furnace oxidizes the target substance in the presence of oxygen.

The second reformer 80 reforms the carbon dioxide-containing gas into a reformed gas containing hydrogen and carbon monoxide.
The second reformer 80 is, for example, a reformer. The reforming furnace reforms the object under high temperature and reducing atmosphere.

The oxygen supply source 75 supplies oxygen to the first reformer 70.
The oxygen supply source is, for example, an oxygen cylinder, a liquefied oxygen storage tank, a fan for taking in air, or the like.

  Each pipe is, for example, a pipe made of stainless steel or the like.

The method for reforming a hydrocarbon-containing gas of the present invention (hereinafter sometimes referred to simply as the reforming method) has a hydrogen separation step, a first reforming step, and a second reforming step.
The method for producing an organic oxygenate of the present invention (hereinafter sometimes referred to simply as the production method) comprises a synthesis step, an oxygenate separation step, and a step of reforming a hydrocarbon-containing gas by the above-mentioned reforming method. .
Hereinafter, the method for producing an organic oxygenate using the production system 1 will be described as an example of the reforming method and the production method of the present invention.

First, a mixed gas containing hydrogen and carbon monoxide is obtained by the gasifier 10 (gasification step). The method of preparing a mixed gas is, for example, a method of gasifying biomass, natural gas, and coal to prepare a mixed gas.
The method of gasifying biomass is, for example, a method of heating pulverized biomass in the presence of water vapor. The heating temperature is, for example, 800 to 1000 ° C.

The mixed gas obtained in the gasification step may contain hydrogen and carbon monoxide.
50 volume% or more is preferable, as for the sum total of hydrogen and carbon monoxide in mixed gas, 80 volume% or more is more preferable, and 90 volume% or more is further more preferable. The higher the content of hydrogen and carbon monoxide, the higher the amount of oxygenated products produced, and the more efficiently oxygenated products can be produced.
The volume ratio represented by hydrogen / carbon monoxide mixed gas _(hereinafter sometimes referred to as H 2 / CO ratio) is preferably from 0.1 to 10, more preferably from 0.5 to 3, 1.5 -2.5 is more preferred. Within the above range, a stoichiometrically appropriate range can be obtained in the synthesis step described later, and oxygenates can be produced more efficiently.
Usually, the mixed gas obtained from biomass contains one or more optional components selected from carbon dioxide, nitrogen, hydrogen sulfide, hydrogen cyanide and hydrocarbons.
As for content of the arbitrary components in mixed gas, 10-40 volume% is preferable, for example, 10-20 volume% is more preferable.

The mixed gas generated in the gasification step flows into the carbon dioxide separator 20 via the pipe 12.
The carbon dioxide separator 20 separates carbon dioxide from the received mixed gas (carbon dioxide separation step). Less than 16.7 mol% is preferable and, as for content of the carbon dioxide in the mixed gas which passed through the carbon dioxide separation process, less than 5.0 mol% is more preferable. If the content of carbon dioxide in the mixed gas is less than the above upper limit value, the hydrogen separation performance in the hydrogen separation step described later can be enhanced.

The separated carbon dioxide (separated carbon dioxide) flows into the second reformer 80 via the pipe 24.
The mixed gas having passed through the carbon dioxide separator 20 flows into the synthesizer 30 through the pipe 22.

  The mixed gas that has flowed into the synthesis device 30 flows through the reaction bed and contacts the synthesis catalyst. During this time, the synthesis catalyst catalyzes a reaction of synthesizing an organic oxygenate such as an alcohol such as ethanol or an aldehyde such as acetaldehyde from hydrogen and carbon monoxide (a synthesis step). Thus, in the synthesis step, the mixed gas is a product gas containing an organic oxygenate.

  150-450 degreeC is preferable, for example, 200-400 degreeC is more preferable, and, as for the reaction temperature in a synthetic | combination process, 250-350 degreeC is further more preferable. If the reaction temperature is equal to or higher than the above lower limit, the reaction rate can be sufficiently increased, and oxygenates can be synthesized more efficiently. If the reaction temperature is equal to or lower than the above upper limit value, the oxygenated compound can be produced more efficiently by mainly using the synthesis reaction of the oxygenated compound.

  The reaction pressure in the synthesis step is, for example, preferably 0.5 to 10 MPa, more preferably 1 to 7.5 MPa, and still more preferably 2 to 5 MPa. If the reaction pressure is equal to or higher than the above lower limit value, the rate of the catalytic reaction can be sufficiently increased to synthesize oxygenate more efficiently. If the reaction pressure is equal to or lower than the above upper limit, the oxygenated compound can be synthesized more efficiently by mainly using the reaction of synthesizing the oxygenated compound.

The space velocity of the mixed gas in the reaction bed (the value obtained by dividing the supply amount of gas per unit time by the amount of catalyst (volume conversion) = SV) is preferably 10 to 100000 L / h / L-catalyst in terms of standard condition, -12000 L / h / L- catalyst is more preferred. If SV is in the above range, the CO conversion can be increased.
SV is appropriately adjusted in consideration of the reaction pressure, reaction temperature and composition of the mixed gas suitable for the target oxygen compound.

  In the synthesis process, not all hydrogen and carbon monoxide can be converted to organic oxygenates. In addition, in the synthesis step, compounds other than organic oxygenates are synthesized. Compounds other than organic oxygenates are C1-C5 hydrocarbons, such as methane, for example. Therefore, the product gas obtained in the synthesis step contains organic oxygenates, unreacted hydrogen and carbon monoxide, hydrocarbons, nitrogen which does not contribute to the reaction, and the like.

The product gas flows into the oxygenate separation device 40 via the pipe 32. The oxygenate separation device 40 separates the organic oxygenate from the product gas, and makes the remainder a hydrocarbon-containing gas containing hydrogen and hydrocarbons (oxygenate separation step).
The content of the organic oxygenate in the hydrocarbon-containing gas is preferably less than 0.1 mol%, more preferably less than 0.05 mol%, and still more preferably less than 0.02 mol%. If it is less than the said upper limit, the reforming efficiency in the first reforming step can be significantly enhanced. The lower limit of the content of organic oxygenates in the hydrocarbon-containing gas is usually 0.01 mol%.
The conditions for separating the organic oxygenate are appropriately determined according to the type of the oxygenate separation device 40.

The separated organic oxygenate flows into the oxygenate storage device 45 via the pipe 44. The hydrocarbon-containing gas flows into the hydrogen separator 50 via the pipe 42. The hydrogen separation device 50 separates hydrogen from the hydrocarbon-containing gas into a first separated gas containing hydrogen and a second separated gas containing hydrocarbons (hydrogen separation step).
The content of hydrogen in the first separated gas is higher than the content of hydrogen in the second separated gas. The content of hydrocarbons in the second separated gas is higher than the content of hydrocarbons in the first separated gas.
The first separated gas has a hydrogen content greater than the hydrocarbon content. The second separated gas has a higher content of hydrocarbons than a content of hydrogen.

The content of hydrogen in the first separated gas is preferably 88.5 to 97.7 mol%, more preferably 90.5 to 97.7 mol%. If the content of hydrogen in the first separated gas is equal to or more than the above lower limit value, hydrogen can be efficiently reused. If it is below the said upper limit, the burden to the hydrogen separation apparatus 50 does not become excessive too much.
The content of hydrogen in the second separated gas is preferably less than 23 mol%, more preferably less than 11.5 mol%. If the content of hydrogen in the second separated gas is less than the upper limit value, hydrocarbons can be efficiently reformed in the first reforming step. The lower limit of hydrogen in the second separated gas is usually 9.5 mol%.
10 mol% or more is preferable and, as for content of the hydrocarbon in 2nd separated gas, 19 mol% or more is more preferable. If the content of hydrocarbons in the second separated gas is equal to or more than the above lower limit value, the hydrocarbons can be efficiently reformed in the first reforming step. The upper limit of the content of hydrocarbons in the second separated gas is usually 20 mol%.
The content of hydrocarbons in the first separated gas is preferably less than 10 mol%, more preferably less than 3 mol%. If the content of hydrocarbons in the first separated gas is less than the above upper limit, hydrogen can be efficiently reused. The lower limit value of hydrocarbons in the first separated gas is usually 2.5 mol%.

  The first separated gas flows into the synthesis device 30 via the pipe 54. The synthesizer 30 utilizes hydrogen in the first separated gas for the synthesis of the organic oxygenate.

  The second separated gas flows into the hydrocarbon separator 60 via the pipe 52. The hydrocarbon separation device 60 separates a part of hydrocarbons in the second separated gas and uses it as separated hydrocarbon gas (hydrocarbon separation step). The second separated gas from which a portion of the hydrocarbon is separated may be referred to as a second separated gas residue.

  In the hydrocarbon separation step, the distribution ratio represented by the second separated gas residue / separated hydrocarbon gas is preferably 1/1 to 10/1 (volume flow ratio), more preferably 3/1 to 7/1. . That is, the distribution ratio is [the amount of gas flowing through the pipe 64] / [the amount of gas flowing through the pipe 62] (volume flow ratio). If the distribution ratio is within the above range, the conversion efficiency to carbon monoxide in the second reforming step is further enhanced.

The separated hydrocarbon gas flows into the second reformer 80 via the pipe 64. The second separated gas remainder flows into the first reformer 70 via the pipe 62.
Oxygen flows from the oxygen supply source 75 into the first reformer 70 via the pipe 74.

  The first reformer 70 synthesizes carbon dioxide from the second separated gas residue and oxygen (first reforming step). In the first reforming step, for example, the reaction of the following formula (a) occurs.

CH ₄ + 2O ₂ COCO ₂ + 2H ₂ O (a)

600-850 degreeC is preferable, for example, and, as for the reaction temperature in a 1st reforming process, 750-850 degreeC is more preferable. If the reaction temperature is within the above range, the conversion efficiency to carbon dioxide can be further enhanced.
The reaction pressure in the first reforming step is, for example, preferably 0.1 to 0.9 MPa, and more preferably 0.5 to 0.9 MPa. If the reaction pressure is within the above range, the conversion efficiency to carbon dioxide can be further enhanced.

  The carbon dioxide-containing gas flows into the second reformer 80 via the pipe 72. In addition, the separated carbon dioxide separated by the carbon dioxide separator 20 flows into the second reformer 80 via the pipe 24. The second reformer 80 synthesizes hydrogen and carbon monoxide from the separated hydrocarbon gas, the carbon dioxide-containing gas and the separated carbon dioxide (second reforming step). In the second reforming step, for example, the reaction of the following formula (b) occurs.

CH ₄ + CO ₂ ⇔2CO + 2H ₂ (b)

The reaction temperature in the second reforming step is, for example, preferably 750 to 1000 ° C., and more preferably 900 to 1000 ° C. If the reaction temperature is within the above range, the conversion efficiency to carbon dioxide can be further enhanced.
The reaction pressure in the second reforming step is, for example, preferably 0.5 to 1.5 MPa, and more preferably 0.9 to 1.0 MPa. If the reaction pressure is within the above range, the conversion efficiency to carbon dioxide can be further enhanced.

The reformed gas obtained in the second reforming step contains hydrogen and carbon monoxide.
The content of hydrogen in the reformed gas is preferably 20 to 40 mol%, and more preferably 30 to 40 mol%.
20-40 mol% is preferable and, as for content of the carbon monoxide in reformed gas, 30-40 mol% is more preferable.
Reforming _H 2 / CO ratio in the gas is preferably from 0.1 to 10, more preferably from 0.5 to 3, more preferably 1.5 to 2.5.

The reformed gas flows into the synthesizing device 30 via the pipe 82.
The total amount of the reformed gas and the separated hydrogen gas (raw material recycling amount) is preferably 100 to 1000 parts by volume, and more preferably 300 to 500 parts by volume with respect to 100 parts by volume of the mixed gas flowing into the synthesizing device 30. That is, 1 to 10 times are preferable and, as for the raw material recycling amount with respect to mixed gas, 3 to 5 times are more preferable.

  The synthesizer 30 utilizes the received reformed gas and separated hydrogen gas for the synthesis of the organic oxygenate.

  In the present embodiment, the reforming method includes a hydrogen separation step, a hydrocarbon separation step, a first reforming step, and a second reforming step.

In the reforming method of the present embodiment, hydrocarbons are converted to carbon dioxide in a first reforming step, and carbon dioxide and hydrocarbons are converted to hydrogen and carbon monoxide in a second reforming step. For this reason, a reforming catalyst for converting hydrocarbons to carbon monoxide is unnecessary. The present embodiment does not cause the problem of performance degradation of the reforming catalyst.
In addition, high temperature steam is not necessary in the first reforming step and the second reforming step. For this reason, the thermal energy for supplying water vapor is unnecessary.
Furthermore, since the hydrogen separation step is provided, the content of hydrogen in various gases supplied to the second reforming step is small. For this reason, in the second reforming step, the rate at which hydrogen and carbon monoxide are produced is advanced, and carbon monoxide can be efficiently synthesized.

Since the manufacturing method of the present embodiment has the above-described reforming method, it is possible to efficiently reuse unreacted hydrogen and carbon monoxide, and a by-product hydrocarbon. Therefore, the productivity of organic oxygenates can be enhanced.
In addition, the manufacturing method of the present embodiment can reuse carbon dioxide separated in the carbon dioxide separation step. Therefore, effective use of resources can be achieved.
Furthermore, the manufacturing method of the present embodiment can maintain the hydrogen concentration and the carbon monoxide concentration of the gas supplied to the reactor at a high concentration. Therefore, the productivity of organic oxygenates can be further enhanced.

The invention is not limited to the embodiments described above.
The reforming system may not include a hydrocarbon separator. However, in order to compensate for the thermal energy in the second reformer, the reforming system preferably comprises a hydrocarbon separator.

  The manufacturing system may not include the gasifier. For example, the manufacturing system may be provided with a mixed gas supply source.

  The manufacturing system may release the first separation gas. However, in order to further improve the productivity of organic oxygenates, it is preferable to supply the first separated gas to the synthesis apparatus.

The manufacturing system may not include the carbon dioxide separator. However, if carbon dioxide is present in the mixed gas, the hydrogen separation performance in the hydrogen separator may be degraded. For this reason, the production system preferably comprises a carbon dioxide separator.
The manufacturing system may emit carbon dioxide separated by the carbon dioxide separator. However, it is preferable to supply separated carbon dioxide to the second reformer in that the productivity of organic oxygenates can be further improved.
For the same reason, the production method preferably has a carbon dioxide separation step.

The reforming system may not include a hydrocarbon separator. However, in order to further improve the productivity of organic oxygenates, it is preferable to include a hydrocarbon separator.
For the same reason, the production method preferably has a hydrocarbon separation step.

  The reforming system may be equipped with an apparatus for separating impurities in the mixed gas, in addition to the carbon dioxide separator. The apparatus for separating the impurities is, for example, an adsorption tower provided with activated carbon or ion exchange resin, an ion exchange membrane, a desulfurization apparatus, a water washing scrubber or the like. The arrangement place of these devices is not particularly limited.

(Manufacture of synthetic catalyst)
Titanium lactate ammonium salt _{(Ti (OH) 2 [OCH} (CH 3) COO -] 2 (NH 4+) 2) was impregnated by dropping an aqueous solution to the spherical silica gel having a particle diameter of 1~2mm including. The resultant was dried at 110 ° C. for 3 hours and calcined at 450 ° C. for 3 hours to obtain a primary carrier. Rhodium chloride trihydrate _{(RhCl 3 · 3H 2 O)} , and lithium chloride monohydrate (LiCl · _H 2 O), the aqueous solution containing manganese chloride tetrahydrate _(MnCl 2 · _4H 2 O) The primary support was dropped and impregnated. The resultant was dried at 110 ° C. for 3 hours and calcined at 400 ° C. for 3 hours to obtain catalyst particles α.

At 320 ° C. while flowing reducing gas (hydrogen concentration 30 volume%, nitrogen concentration 70 volume%) at a pressure of 6000 L / h / L at atmospheric pressure into a stainless steel cylindrical reactor filled with catalyst particles α After heating for 2 hours, the synthesis catalyst was subjected to reduction treatment. The ratio of rhodium, manganese, lithium and titanium constituting the synthesis catalyst was Rh: Mn: Li: Ti = 1.00: 0.750: 0.275: 0.143 (molar ratio). Further, the rhodium loading rate was 3% by mass / SiO ₂ .

Example 1
A production system similar to the production system 1 of FIG. 1 was produced.
In the production system of this example, a gas cylinder filled with combustion gas generated from a waste incineration facility was used instead of the gasifier. Moreover, each apparatus was made into the following specification.
Hereinafter, the method for producing the organic oxygenate in the present example will be described.
First, mixed gas was supplied to the carbon dioxide separator 20 from a gas cylinder. Carbon dioxide was separated by the carbon dioxide separator 20 (carbon dioxide separation step). The separated carbon dioxide was released into the atmosphere. The mixed gas processed by the carbon dioxide separator 20 was supplied to the synthesizer 30. The synthesis device 30 produced a product gas containing an organic oxygenate (synthesis step). The product gas was supplied to the oxygenate separator 40. The oxygenate separation device 40 separated the product gas into the organic oxygenate and the remainder (hydrocarbon-containing gas) (oxygenate separation step). The organic oxygenate was supplied to the oxygenate storage device 45. The hydrocarbon-containing gas (hydrocarbon content = 20.3 mol%) was supplied to the hydrogen separator 50. The hydrogen separator 50 separates the hydrocarbon-containing gas into a first separated gas and a second separated gas (hydrogen separation step). The first separated gas was supplied to the synthesizer 30. The second separated gas (hydrogen content = 9.5 mol%) was fed to the hydrocarbon separator 60. The hydrocarbon separation device 60 separated the second separated gas into separated hydrocarbon gas and the remaining second separated gas. The separated hydrocarbon gas was supplied to the second reformer 80. The second separated gas residue was supplied to the first reformer 70. Oxygen was supplied from the oxygen supply source 75 to the first reformer 70. The first reformer 70 reforms the remaining part of the second separated gas into a carbon dioxide-containing gas (content of carbon dioxide = 40 mol%). The carbon dioxide-containing gas was supplied to the second reformer 80. The second reformer 80 reforms the carbon dioxide-containing gas into a reformed gas. The reformed gas was supplied to the synthesizer 30.
As a result, 27.3 g of acetaldehyde and 3.2 g of ethanol were obtained per 1 m ^{3 of} mixed gas.
The production conditions of this example are as follows.

<Specification of manufacturing system>
-Carbon dioxide separation device: amine absorption type removal device.
Synthesizer: A reaction tower packed with the synthesis catalyst obtained by the method for producing a synthesis catalyst described above.
・ Oxygen separator: Cooler.
-Hydrogen separation device: A separation device equipped with a hydrogen separation membrane (manufactured by Ube Industries, Ltd.).
・ Hydrocarbon separator: Activated carbon adsorption tank.
First reformer: combustion furnace.
Second reformer: Reformer.

<Manufacturing conditions>
Mixed gas: H ₂ / CO ratio = 50.1 / 25.2. Carbon dioxide content = 10 mol%.
Synthesis step: reaction temperature 280 ° C., reaction pressure 2.0 MPa, SV = 3000 L / h / L-catalyst.
・ Distribution ratio: 3/1.
First reforming step: reaction temperature = 35 ° C., reaction pressure = 1.6 MPa.
Second reforming step: reaction temperature = 800 ° C., reaction pressure = 0.5 MPa.
-Raw material reuse amount: 6 times.

(Comparative example 1)
A manufacturing system similar to the manufacturing system 101 of FIG. 2 was produced.
Hereinafter, the same components as those of the manufacturing system 1 are denoted by the same reference numerals, and the description thereof is omitted.
The manufacturing system 101 includes a mixed gas supply source 110, a carbon dioxide separator 120, a synthesizer 30, an oxygenate separator 40, a reformer 180, an exhaust device 125, an oxygenate storage device 45, and steam. And a supply source 185.
The manufacturing system 101 further includes a pipe 12, a pipe 22, a pipe 126, a pipe 32, a pipe 44, a pipe 142, a pipe 182, and a pipe 184.
The pipe 12 connects the mixed gas supply source 110 and the carbon dioxide separator 120. The pipe 22 connects the carbon dioxide separator 120 and the synthesizer 30. The pipe 126 connects the carbon dioxide separator 120 and the exhaust device 125. The pipe 142 connects the oxygenate separator 40 to the reformer 180. The pipe 182 connects the reforming device 180 and the synthesizing device 30. The pipe 184 connects the reformer 180 and the water vapor supply source 185.
Each device has the following specifications.

First, the mixed gas was supplied from the mixed gas supply source 110 to the carbon dioxide separator 120. Carbon dioxide was separated by the carbon dioxide separator 120. The separated carbon dioxide was released to the atmosphere by the exhaust system 125. The mixed gas processed by the carbon dioxide separator 120 was supplied to the synthesizer 30. The product gas containing the organic oxygenate was supplied from the synthesizer 30 through the pipe 32 to the oxygenate separator 40. The oxygenate separation device 40 separated the organic oxygenate and the remainder (hydrocarbon-containing gas). The organic oxygenate was supplied to the oxygenate storage device 45. The hydrocarbon-containing gas (hydrocarbon content = 25 mol%) was supplied to the reformer 180. Steam was supplied from the steam supply source 185 to the reformer 180. The reformer 180 reforms the hydrocarbon-containing gas into a reformed gas. The hydrogen content of the reformed gas was 36.5 mol%. The carbon monoxide content of the reformed gas was 17.2 mol%. The reformed gas was supplied to the synthesizer 30.
As a result, 18.6 g of acetaldehyde and 2.2 g of ethanol were obtained per 1 m ^{3 of} mixed gas.
The production conditions of this example are as follows.

<Specification of manufacturing system>
Mixed gas supply source: Gas cylinder filled with combustion gas generated from waste incineration facility.
-Carbon dioxide separation device: amine absorption type removal device.
Synthesizer: A reaction tower packed with the above synthesis catalyst.
・ Oxygen separator: Cooler.
-Reformer: Reformer.

<Manufacturing conditions>
Mixed gas: H ₂ / CO ratio = 41.5 / 20.2. Carbon dioxide content = 23 mol%.
Synthesis step: reaction temperature 280 ° C., reaction pressure 2.0 MPa, SV = 3000 L / h / L-catalyst.
Reformer: reaction temperature 800 ° C., reaction pressure 0.9 MPa.
-Raw material reuse amount: 6 times.

  From the results of Example 1 and Comparative Example 1, it was confirmed that the productivity of organic oxygenates can be enhanced by applying the present invention.

DESCRIPTION OF SYMBOLS 1 Organic oxygenate production system 2 Reforming system of hydrocarbon-containing gas 10 Gasification apparatus 20 Carbon dioxide separation apparatus 30 Synthesis apparatus 40 Oxygenate separation apparatus 50 Hydrogen separation apparatus 60 Hydrocarbon separation apparatus 70 First reformer 80 Second reformer 12, 22, 24, 32, 42, 44, 52, 54, 62, 64, 72, 74, 82 Piping

Claims (10)

Hydrogen is separated from a hydrocarbon-containing gas containing hydrogen and hydrocarbons to form a first separated gas containing hydrogen and a second separated gas containing hydrocarbons;
The second separated gas is reformed into a carbon dioxide-containing gas containing carbon dioxide,
A method for reforming a hydrocarbon-containing gas, comprising reforming the carbon dioxide-containing gas to obtain a reformed gas containing hydrogen and carbon monoxide. Bringing a mixed gas containing hydrogen and carbon monoxide into contact with a synthesis catalyst to form a product gas containing an organic oxygenate, hydrogen and a hydrocarbon,
Separating the organic oxygenate from the product gas, with the balance being hydrogen and a hydrocarbon-containing gas comprising hydrocarbons,
Hydrogen is separated from the hydrocarbon-containing gas into a first separated gas containing hydrogen and a second separated gas containing hydrocarbons;
The second separated gas is reformed into a carbon dioxide-containing gas containing carbon dioxide,
Reforming the carbon dioxide-containing gas into a reformed gas containing hydrogen and carbon monoxide,
A method for producing an organic oxygenate, comprising contacting the reformed gas with the synthesis catalyst.   The organic oxygenated product according to claim 2, wherein a part of hydrocarbon is separated from the second separated gas, and the separated hydrocarbon and the carbon dioxide-containing gas are reformed to be the reformed gas. Method.   The method for producing an organic oxygenate according to claim 2 or 3, wherein carbon dioxide is separated from the mixed gas, and the separated carbon dioxide is reformed together with the carbon dioxide-containing gas to obtain the reformed gas.   The method for producing an organic oxygenate according to any one of claims 2 to 4, wherein the first separated gas is brought into contact with the synthesis catalyst. Separating hydrogen from a hydrocarbon-containing gas comprising hydrogen and hydrocarbons into a first separated gas comprising hydrogen and a first separator comprising a second separated gas comprising hydrocarbons;
A first reformer for reforming the second separated gas into a carbon dioxide-containing gas containing carbon dioxide;
And a second reformer for reforming the carbon dioxide-containing gas into a reformed gas containing hydrogen and carbon monoxide. A synthesis apparatus for bringing a mixed gas containing hydrogen and carbon monoxide into contact with a synthesis catalyst to form a product gas containing an organic oxygenate, hydrogen and a hydrocarbon;
An oxygenate separation device that separates the organic oxygenate from the product gas and uses the balance as a hydrocarbon-containing gas including hydrogen and a hydrocarbon;
Hydrogen is separated from the hydrocarbon-containing gas into a first separated gas containing hydrogen and a second hydrogen-containing separated gas containing hydrogen;
A first reformer for reforming the second separated gas into a carbon dioxide-containing gas containing carbon dioxide;
A second reformer which reforms the carbon dioxide-containing gas into a reformed gas containing hydrogen and carbon monoxide;
And a pipe for supplying the reformed gas to the synthesis apparatus.   8. The apparatus according to claim 7, further comprising: a hydrocarbon separator for separating a part of hydrocarbons from the second separated gas; and a pipe for supplying the separated hydrocarbon and the carbon dioxide-containing gas to the first reformer. The organic oxygenate production system according to claim 1.   The organic oxygenate production system according to claim 7 or 8, further comprising: a carbon dioxide separator for separating carbon dioxide from the mixed gas; and a pipe for supplying the separated carbon dioxide to the second reformer.   The system for producing an organic oxygenated product according to any one of claims 7 to 9, further comprising: a pipe for supplying the first separated gas to the synthesis apparatus.

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