JP2005023043A - Apparatus for and method of producing dimethyl ether from organic wastes - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for and a method of efficiently producing dimethyl ether using the fermented methane gas from organic wastes. <P>SOLUTION: This apparatus is provided with a methane fermentation device 13 for obtaining the fermented methane gas (CH<SB>4</SB>) 12 by fermenting the organic wastes 11, a removal means 15 for removing impurities in the fermented methane gas 12, a reforming unit 16 for reforming the impurities-removed methane gas 14, a methanol synthesizing device 19 for synthesizing methanol (CH<SB>3</SB>OH) 18 using the reformed synthesis gas 17, and a dimethyl ether synthesis device 21 for synthesizing dimethyl ether (DME) 20 from the synthesized methanol 19. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and a method for producing dimethyl ether from organic waste, which can consistently and efficiently produce dimethyl ether from organic waste.
[0002]
[Prior art]
Conventionally, various treatment methods such as incineration treatment, landfill treatment, and compost (composting) treatment have been performed on organic waste such as garbage. However, the incineration process generates pollutants such as dioxins, the landfill process has problems such as land subsidence and leachate, and the compost process requires a stable supply destination. .
[0003]
For this reason, various methane fermentation processes using anaerobic microorganisms have been proposed as effective utilization of organic waste. In this technique, organic waste is pulverized by, for example, a pulverizer and then added to form a slurry, and methane gas is fermented by anaerobic microorganisms such as methane fermentation bacteria (Patent Document 1).
[0004]
Meanwhile, a hydrocarbon gas composed mainly of methane, such as natural gas steam reforming, CO, from the conversion of H ₂ in the synthesis gas mainly composed, on the methanol synthesis catalyst, a technology for converting methanol Various proposals have been made (Patent Document 2).
[0005]
Various techniques for converting liquid dimethyl ether on a catalyst using liquid methanol have been proposed (Patent Document 3).
[0006]
[Patent Document 1]
JP 2000-167523 A [Patent Document 2]
JP 2001-97905 A [Patent Document 3]
Japanese Patent Laid-Open No. 2003-73320
[Problems to be solved by the invention]
However, although the above-mentioned technologies are being commercialized independently, there is currently no proposal for a processing system that consistently performs them.
This is because the fermented methane gas obtained by methane fermentation is a gas, so that it is difficult to store and transport, and is limited to use around the apparatus.
[0008]
In addition, since the technology for synthesizing methanol from natural gas uses natural gas, which is a fossil fuel, as a raw material, there is a problem that the construction of facilities is limited to the region where natural gas is produced.
[0009]
In addition, since the technology for synthesizing dimethyl ether uses liquid methanol as a raw material, it is limited to areas that produce a large amount of methanol, in the vicinity of factories, or to transport and use industrial methanol. is there.
[0010]
Moreover, since the fermentation methane gas obtained by methane fermentation contains impurities that poison the steam reforming catalyst and the methanol synthesis catalyst, it is necessary to remove the impurities.
[0011]
Furthermore, methane fermentation has a problem in consistently producing dimethyl ether using this fermented methane gas because the amount of fermented methane gas produced is not stable due to the content of the organic waste supplied. That is, when reforming methane, when compressing fermented methane gas to a predetermined pressure, if the amount of gas is not constant, it is necessary to provide a primary storage means such as a gas tank. However, there is a problem that a large capacity tank is required.
[0012]
This invention makes it a subject to provide the dimethyl ether manufacturing apparatus and method from organic waste which can manufacture dimethyl ether efficiently using the fermentation methane gas from organic waste in view of the said problem. .
[0013]
[Means for Solving the Problems]
1st invention which solves the subject mentioned above is a methane fermentation apparatus which ferments organic waste and manufactures fermentation methane gas, a removal means which removes impurities in fermentation methane gas, and reforms methane gas from which impurities were removed Dimethyl ether from organic waste, comprising: a reformer that synthesizes methanol using the reformed gas; and a dimethyl ether synthesizer that synthesizes dimethyl ether from the synthesized methanol. In production equipment.
According to this invention, by removing impurities in the fermented methane gas with a removal device, it is possible to prevent catalyst poisoning of a reformer that reforms methane and a synthesis device that synthesizes methanol or dimethyl ether. Therefore, it is possible to synthesize consistently and stably.
[0014]
The second invention is a methane fermentation apparatus for producing fermented methane gas by fermenting organic waste, a removing means for removing impurities in the fermented methane gas, and a mixing means for mixing natural gas into the fermented methane gas from which impurities have been removed. A reformer that reforms mixed methane gas of fermented methane gas and natural gas, a methanol synthesizer that synthesizes methanol using the reformed gas, and a dimethyl ether synthesizer that synthesizes dimethyl ether from the synthesized methanol It is in the dimethyl ether manufacturing apparatus from the organic waste characterized by comprising.
According to this invention, since natural gas is supplied to the fermentation methane gas from which impurities have been removed, a constant gas amount can always be supplied to the reformer even if the fermentation amount of the fermentation methane gas varies.
[0015]
The third invention is a methane fermentation apparatus for fermenting organic waste to produce fermented methane gas, a mixing means for mixing natural gas into the fermented methane gas, a removing means for removing impurities in the mixed methane gas, and impurities. An organic apparatus comprising: a reformer that reforms the removed methane gas; a methanol synthesizer that synthesizes methanol using the reformed gas; and a dimethyl ether synthesizer that synthesizes dimethyl ether from the synthesized methanol. It is in the dimethyl ether production equipment from the system waste.
According to the present invention, since impurities that are catalyst poisoning components in the fermented methane gas and natural gas are removed, stable and consistent synthesis can be achieved over a long period of time.
[0016]
According to a fourth aspect of the present invention, in the second aspect of the invention, the natural gas is city gas, and a fragrance removal device for removing the fragrance of the city gas is provided. In the device.
According to the present invention, when the natural gas is city gas, the scented product is removed, so that the scented product such as hydrogen sulfide can be removed and catalyst poisoning can be prevented.
[0017]
According to a fifth invention, in any one of the second to fourth inventions, there is provided an apparatus for producing dimethyl ether from organic waste, comprising control means for controlling a gas supply amount of natural gas.
According to this invention, the supply amount of natural gas can be controlled according to the fermentation amount of fermented methane gas.
[0018]
A sixth invention is characterized in that, in the fifth invention, the control means has a measuring means for measuring the flow rate of the fermentation methane gas, and controls the supply of natural gas according to the fluctuation of the fermentation amount of the fermentation methane gas. It is in dimethyl ether production equipment from organic waste.
According to this invention, since supply of natural gas is controlled according to the fluctuation | variation of the fermentation amount of fermentation methane gas, the supply amount of natural gas can be controlled according to the fluctuation | variation amount of fermentation methane gas.
[0019]
The seventh invention is to ferment organic waste into fermented methane gas, remove impurities in the fermented methane gas, modify the methane gas to synthesize methanol, and then synthesize dimethyl ether from the obtained methanol. The feature is a method for producing dimethyl ether from organic waste.
[0020]
According to an eighth invention, in the seventh invention, there is provided a method for producing dimethyl ether from organic waste, characterized in that natural gas is supplied according to the amount of fermented methane gas.
According to the present invention, since natural gas rich in methane is supplied according to the fermentation amount of fermented methane gas, the stable supply amount of methane can be controlled.
[0021]
A ninth invention is the method for producing dimethyl ether from organic waste, characterized in that, in the eighth invention, the natural gas is a city gas and hydrogen sulfide is removed and then supplied to the fermented methane gas.
According to the present invention, when the natural gas is city gas, the scented product is removed, so that the scented product such as hydrogen sulfide can be removed and catalyst poisoning can be prevented.
[0022]
A tenth aspect of the invention is the production of dimethyl ether from organic waste according to the eighth or ninth aspect, wherein the flow rate of the fermentation methane gas is measured, and natural gas is supplied according to the change in the fermentation amount of the fermentation methane gas. Is in the way.
According to this invention, since supply of natural gas is controlled according to the fluctuation | variation of the fermentation amount of fermentation methane gas, the supply amount of natural gas can be controlled according to the fluctuation | variation amount of fermentation methane gas.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Although the form of this invention is demonstrated below, this invention is not limited to these embodiment.
[0024]
[First Embodiment]
The apparatus according to this embodiment will be described with reference to FIG.
As shown in FIG. 1, the dimethyl ether production apparatus from the organic waste according to the present embodiment includes a methane fermentation apparatus 13 that ferments an organic waste 11 to produce fermented methane gas (CH ₄ ) 12, and a fermentation. Methanol (CH ₃ OH) 18 is synthesized using removal means 15 for removing impurities in methane gas 12, reformer 16 for reforming impurity-removed methane gas 14 from which impurities have been removed, and reformed synthesis gas 17. And a dimethyl ether synthesizer 21 that synthesizes dimethyl ether (DME) 20 from the synthesized methanol 18.
[0025]
In the present embodiment, a compressor 22 that compresses the impurity-removed methane gas 14 supplied to the reformer 16 to a predetermined pressure is provided on the upstream side of the reformer 16, and the synthesis gas 17 supplied to the methanol synthesizer 19. Is provided upstream of the methanol synthesizer 19. The compressor 23 is compressed to a predetermined pressure (for example, 50 to 150 atmospheres).
[0026]
The reformer 16 is provided with a reforming reaction tube 16a having a heating means, and the reaction tube 16a is filled with a reforming catalyst such as a nickel-based catalyst. In addition, a predetermined water vapor 24 is supplied from the outside to the gas compressed by the compressor 22 for the steam reforming reaction.
[0027]
In addition, a heat exchanger 25 is interposed between the reformer 16 and the synthesis gas compressor 23 in order to effectively use the heat in the synthesis gas 17 reformed by the reformer 16.
[0028]
Here, as the organic waste 11, for example, raw sewage sludge, surplus sludge from activated sludge treatment, pumped urine, livestock waste, pulp mill waste water, various food industries (bakery yeast production, fruit processing, sugar production, starch production) , Wastewater from the production of alcohol such as wine and beer) and fermented industrial water.
[0029]
The methane fermentation apparatus 13 generates methane by anaerobic fermentation, and treats organic waste by utilizing the metabolic activity of known anaerobic microorganisms.
[0030]
Examples of the removing means 15 for removing impurities such as S component which are catalyst poisoning substances in the fermented methane gas 12 obtained by the methane fermentation apparatus 13 include a removing means by a dry method and a removing means by a wet method. it can. Examples of the removing means by the dry method include a removing means using an adsorbent such as activated carbon. On the other hand, examples of the removing means by a wet method include a removing means using an adsorbing liquid such as an amine adsorbing liquid. Moreover, you may make it combine both means.
[0031]
The impurity-removed methane gas 14 from which impurities have been removed is compressed to a predetermined pressure by the compressor 22, and then steam 24 is supplied and then introduced into the reformer 16. The impurity-removed methane gas 14 is heated to a sufficiently high temperature (for example, 850 to 900 ° C.) in the reaction tube 16a of the reformer 16. The reason why the impurity-removed methane gas 14 is heated is that the reforming reaction in the reformer 16 is an endothermic reaction.
[0032]
The impurity-removed methane gas 14 supplied to the reaction tube 16a of the reformer 16 is mainly steam-reformed in the presence of the catalyst in the reaction tube 16a, and the formula (1) shown in the following “chemical formula 1”, According to (2), a synthesis gas containing hydrogen, carbon monoxide and carbon dioxide is generated.
[0033]
[Chemical 1]
CH ₄ + H ₂ O → CO + 3H ₂ (1)
CO + H ₂ O → CO ₂ + H ₂ (2)
[0034]
In the reforming formulas (1) and (2), 4 moles of hydrogen and 1 mole of carbon dioxide are generated by the reaction of 1 mole of methane and 2 moles of steam. However, in an actual reaction system, a composition close to the chemical reaction equilibrium composition determined from the temperature and pressure at the outlet of the reaction tube can be obtained.
[0035]
The high-temperature synthesis gas 17 generated by the reformer 16 heats boiler water, for example, in a heat exchanger 25 interposed in the flow path, and generates high-pressure steam.
[0036]
The synthesis gas 17 heat-exchanged by the heat exchanger 25 is compressed to a predetermined pressure (for example, 50 to 150 atmospheres) by the synthesis gas compressor 23 and then reaches the methanol synthesis apparatus 19.
[0037]
In the methanol synthesizer 19, a product containing methanol 18 synthesized by the reaction shown in the following formulas (3) and (4) shown in the following “chemical formula 2” in the presence of a methanol synthesis catalyst such as copper and zinc is obtained. .
[0038]
[Chemical formula 2]
CO + 2H ₂ → CH ₃ OH (3)
CO ₂ + 3H ₂ → CH ₃ OH + H ₂ O (4)
[0039]
The synthesized methanol becomes a product containing dimethyl ether 20 in the dimethyl ether synthesizer 21 in the presence of a dehydration catalyst such as alumina, by the reaction shown in the following formula (5).
[0040]
[Chemical formula 3]
2CH ₃ OH → CH ₃ OCH ₃ + H ₂ O (5)
[0041]
With the configuration as described above, catalyst poisoning is eliminated by removing impurities (for example, S component) in the fermentation methane gas 12 generated in the methane fermentation apparatus 13 by the removing means 15, and organically stable for a long period of time. Dimethyl ether (DME) 20 can be synthesized from the system waste 11 via methanol (CH ₃ OH) 18.
[0042]
[Second Embodiment]
In the present embodiment, natural gas is supplied in the first embodiment. FIG. 2 shows an outline of an apparatus for producing dimethyl ether from organic waste according to the present embodiment. In addition, about the member which overlaps with the apparatus concerning 1st Embodiment shown in FIG. 1, the same number is attached | subjected and the description is abbreviate | omitted.
First, in the present embodiment, the amount of fermented methane gas 12 generated by the methane fermentation apparatus 13 may vary depending on the fermentation conditions, such as the type of garbage to be charged. The natural gas contained in is supplied.
As this natural gas, for example, city gas having a constant composition can be exemplified, and natural gas can be easily obtained particularly in a place where there is a methane fermentation facility by waste treatment in an urban area.
[0043]
FIG. 2 shows a case in which the city gas 31 is supplied in the apparatus of the first embodiment, and a fragrance removal means 32 for removing the fragrance attached to the city gas 31 is provided. . And the city gas which removed the fragrance | flavor is supplied to the gas flow path 34 of the methane gas 14 which removed the impurity in fermentation methane gas, and both are mixed in the mixing part 35. FIG.
[0044]
Thereby, even if there is a change in the amount of fermented methane gas in the methane fermentation apparatus 13, a predetermined amount of gas can always be supplied to the compressor 22 by supplying natural gas such as city gas.
[0045]
Moreover, since the large-sized fermentation gas tank etc. for temporarily storing fermentation gas are not provided unlike the past, the whole apparatus can be made compact.
The supply of the natural gas may be performed by a control means (not shown) that controls the natural gas supply according to the shortage of fermentation gas.
[0046]
[Third Embodiment]
In the present embodiment, in the second embodiment, the city gas 31 is mixed with the fermentation methane gas 12 in advance, and then impurities in the fermentation methane gas and perfumes in the city gas are removed by the removing means. Is. FIG. 3 shows an outline of an apparatus for producing dimethyl ether from organic waste according to the present embodiment. In addition, about the member which overlaps with the apparatus concerning 1st Embodiment shown in FIG. 1, the same number is attached | subjected and the description is abbreviate | omitted.
[0047]
FIG. 3 shows a case where the city gas 31 is premixed with the fermented methane gas in the apparatus of the second embodiment, and the city gas 31 having a constant composition is supplied to the gas flow path 42 of the fermented methane gas 12, and the mixing unit In 43, both are mixed and the mixed gas 40 is obtained.
[0048]
In the present embodiment, flow meters F ₁ and F ₂ , which are measuring means for measuring the amount of fermentation methane gas 12 and the amount of city gas 31 supplied, are installed in the gas flow paths 42 and 44, and the fermentation gas The gas supply amount of city gas is adjusted according to the amount change.
[0049]
As a result, the methane gas supply amount is adjusted by the flow meter F ₂ so that the optimum amount of methane is always obtained while confirming the fermentation amount of the fermented methane gas with the flow meter F ₁ , so that a predetermined amount is always supplied to the compressor 22. As a result, the capacity of the compressor can be optimized, and a stable amount of compressed gas can be supplied to the reformer 16.
[0050]
【The invention's effect】
According to the present invention, it is possible to remove the catalyst poisoning component in the fermented methane gas obtained from the organic waste, and to generate a stable synthesis gas. Further, in the synthesis of dimethyl ether from methanol, there is no catalyst poisoning. Therefore, it is possible to synthesize it stably and consistently produce from organic waste to dimethyl ether.
[Brief description of the drawings]
FIG. 1 is a diagram showing an apparatus for producing dimethyl ether from organic waste according to a first embodiment.
FIG. 2 is a diagram showing an apparatus for producing dimethyl ether from organic waste according to a second embodiment.
FIG. 3 is a diagram showing an apparatus for producing dimethyl ether from organic waste according to a third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Organic waste 12 Fermentation methane gas 13 Methane fermentation apparatus 14 Impurity removal methane gas 15 Impurity removal means 16 Reformer 17 Synthesis gas 18 Methanol 19 Methanol synthesis apparatus 20 Dimethyl ether 21 Dimethyl ether synthesis apparatus

Claims (10)

A methane fermentation device that ferments organic waste to produce fermented methane gas;
Removing means for removing impurities in the fermentation methane gas;
A reformer for reforming methane gas from which impurities have been removed;
A methanol synthesizer that synthesizes methanol using the modified gas; and
An apparatus for producing dimethyl ether from organic waste, comprising: a dimethyl ether synthesis apparatus for synthesizing dimethyl ether from synthesized methanol. A methane fermentation device that ferments organic waste to produce fermented methane gas;
Removing means for removing impurities in the fermentation methane gas;
Mixing means for mixing natural gas with fermented methane gas from which impurities have been removed;
A reformer for reforming mixed methane gas of fermented methane gas and natural gas;
A methanol synthesizer that synthesizes methanol using the modified gas; and
An apparatus for producing dimethyl ether from organic waste, comprising: a dimethyl ether synthesis apparatus for synthesizing dimethyl ether from synthesized methanol. A methane fermentation device that ferments organic waste to produce fermented methane gas;
Mixing means for mixing natural gas with fermented methane gas;
Removing means for removing impurities in the mixed methane gas;
A reformer for reforming methane gas from which impurities have been removed;
A methanol synthesizer that synthesizes methanol using the modified gas; and
An apparatus for producing dimethyl ether from organic waste, comprising: a dimethyl ether synthesis apparatus for synthesizing dimethyl ether from synthesized methanol. In claim 2 or 3,
An apparatus for producing dimethyl ether from organic waste, characterized in that natural gas is city gas, and a scented material removing device for removing a scented material from city gas is provided. In any one of Claims 2 thru | or 4,
An apparatus for producing dimethyl ether from organic waste, comprising a control means for controlling a gas supply amount of natural gas. In claim 5,
An apparatus for producing dimethyl ether from organic waste, wherein the control means has measuring means for measuring the flow rate of the fermented methane gas and controls the supply of natural gas according to the fluctuation of the fermentation amount of the fermented methane gas. Organic waste is characterized by fermenting organic waste into fermented methane gas, removing impurities in the fermented methane gas, modifying the methane gas to synthesize methanol, and then synthesizing dimethyl ether from the resulting methanol Method for producing dimethyl ether from product. In claim 7,
A method for producing dimethyl ether from organic waste, characterized by supplying natural gas according to the amount of fermented methane gas. In claim 8,
A method for producing dimethyl ether from organic waste, characterized in that natural gas is city gas and hydrogen sulfide is removed and then fed to fermented methane gas. In claim 8 or 9,
A method for producing dimethyl ether from organic waste, characterized in that the flow rate of fermented methane gas is measured, and natural gas is supplied according to fluctuations in the fermentation amount of fermented methane gas.

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