KR20210043252A - Method for preparing methanol from carbon dioxide-containing gas resources comprising dry-reforming of methane by plasma - Google Patents

Abstract

The present invention relates to a method for manufacturing methanol from carbon dioxide-containing methane gas. More specifically, the present invention relates to a method for manufacturing methanol comprising: a first step of partially removing hydrogen sulfide contained in carbon dioxide-containing methane gas; a second step of producing a synthesis gas from the carbon dioxide-containing methane gas obtained from the previous step by a dry reforming reaction using plasma; a third step of controlling the composition of the synthesis gas by supplying hydrogen to the synthesis gas obtained from the previous step; and a fourth step of manufacturing methanol from the synthesis gas whose composition has been adjusted.

Description

Method for preparing methanol from carbon dioxide-containing gas resources comprising dry-reforming of methane by plasma

The present invention relates to a method for producing methanol from carbon dioxide-containing methane gas, specifically, a first step of removing some hydrogen sulfide contained in the carbon dioxide-containing methane gas; A second step of producing a synthesis gas by a dry reforming reaction using plasma from the carbon dioxide-containing methane gas obtained from the previous step; A third step of supplying hydrogen to the synthesis gas obtained from the previous step to control the composition of the synthesis gas; And a fourth step of preparing methanol from the syngas whose composition is controlled.

Landfill gas or biogas is produced when organic matter is anaerobicly decomposed through a digestion process, and its main components are methane and carbon dioxide, and as impurities, hydrogen sulfide, siloxane, ammonia, and volatile organic compounds are included.

In general, landfill gas or biogas has been used to generate electricity by gas engines or gas turbines or as a heat source for boilers. In order to utilize these gases, it is necessary to use them through a pretreatment process to remove impurities such as hydrogen sulfide or siloxane compounds. In addition, in order to use these gases as a heat source as a heat source, an additional process of removing carbon dioxide is required.

Gas resources such as methane, which make up the majority of natural gas, are mainly used for power generation or household heat sources, but some are used as raw materials for producing liquid fuels or chemicals. Most of the methane conversion reaction for this is through the reforming reaction of methane, which is a synthesis gas manufacturing process. These syngases are used as raw materials for methanol synthesis, hydrogen production, ammonia production, or synthetic oil production processes by Fischer-Tropsch reaction.

The reforming reaction of methane is a strong endothermic reaction as shown in the following reaction equation. That is, in order for the methane reforming reaction to occur, a lot of heat must be supplied from the outside.

CH ₄ + H ₂ O --> CO + 3 H ₂ , ΔH _298K = 206.2 kJ/mol 1)

CH ₄ + CO ₂ --> 2 CO + 2 H ₂ , ΔH _298K = 247.2 kJ/mol 2)

CH ₄ + 2/3H ₂ O + 1/3CO ₂ --> 4/3CO + 8/3H ₂ , ΔH _298K = 220.0 kJ/mol 3)

CH ₄ --> C + 2H ₂ , ΔH _298K = 76 kJ/mol 4)

On the other hand, the reaction formula of the reaction for synthesizing methanol in the synthesis gas is as follows. As shown in Equations 5) and 6) below, the reaction of synthesizing methanol by hydrogenation of carbon monoxide and carbon dioxide is an exothermic reaction. It can be seen that one carbon monoxide molecule reacts with two hydrogen molecules, and one carbon dioxide reacts with three hydrogens to make methanol. That is, it can be seen that when methanol is synthesized by hydrogenation of a mixture of carbon monoxide and carbon dioxide, the ratio of H ₂ /(2CO + 3CO ₂ ) should be 1.

_{CO + 2H 2 ↔ CH 3 OH} ΔH 298K = -90.8 kJ / mol 5)

_{CO 2 + 3H 2 ↔ CH 3} OH + H 2 O ΔH 298K = -49.6 kJ / mol 6)

CO ₂ + H ₂ ↔ CO + H ₂ O ΔH _298K = 41.1 kJ/mol 7)

On the other hand, since landfill gas or biogas contains 30 to 60% of carbon dioxide in addition to methane, the composition of the synthesis gas generated through the reforming reaction of methane gas containing a large amount of carbon dioxide as shown in Equation 2 above is H ₂ /CO. The ratio is about 1, and the amount of hydrogen is insufficient to be used in the Fischer-Tropsch reaction or the methanol synthesis reaction as it is.

In addition, renewable energy, which is energy that can be obtained from renewable resources such as wind, solar, geothermal, and tidal power, is increasing in importance as the climate change problem deepens, and its output is gradually increasing. Hydrogen can be produced by performing electrolysis of water as shown in Equation 8 below using electric energy obtained from such renewable resources such as sunlight and wind power.

H ₂ O + e Energy --> 1/2O ₂ + H ₂ 8)

However, these renewable resources such as solar or wind power have a problem of intermittent power generation, which is difficult to continuously supply because the amount of power generation is not constant due to the influence of day-night, weather, or season. Therefore, when the amount of renewable energy generation increases, these surplus intermittent electrical energy has problems in storage or use, so in the case of using the hydrogen produced from water by electrolyzing water using their inexpensive and low-quality electrical energy, the existing There is an advantage that it can increase the economics of the process.

As a result of intensive research efforts to discover a simple and economical process that can efficiently produce methanol, a material important for the chemical industry, from gas resources containing a large amount of carbon dioxide such as landfill gas or biogas, Synthetic gas is produced by removing some hydrogen sulfide contained in gas resources containing a large amount of carbon dioxide, such as gas, and then producing synthetic gas by a dry reforming reaction using plasma, and supplying hydrogen produced by electrolysis of water using renewable energy. It was confirmed that methanol can be efficiently produced without a cumbersome process for removing impurities other than hydrogen sulfide or controlling the gas composition by separately removing carbon dioxide by preparing methanol from the syngas whose composition is adjusted, and the present invention Was completed.

A first aspect of the present invention provides a method for producing methanol from carbon dioxide-containing methane gas, comprising: a first step of partially removing hydrogen sulfide contained in carbon dioxide-containing methane gas; A second step of producing a synthesis gas by a dry reforming reaction using plasma from the carbon dioxide-containing methane gas obtained from the previous step; A third step of supplying hydrogen to the synthesis gas obtained from the previous step to control the composition of the synthesis gas; And a fourth step of preparing methanol from the syngas whose composition is adjusted.

A second aspect of the present invention provides a method for producing methanol from a landfill gas or biogas, comprising: a step a of dehumidifying and partial desulfurization by pretreating the landfill gas or biogas; A step b of preparing a syngas by a dry reforming reaction using plasma at a pressure of 0.1 to 5 atmospheres of the pretreated gas obtained from the previous step; A step c of cooling the synthesis gas obtained from the previous step at 0 to 50°C, filtering to remove particulate impurities, and then passing through a dry desulfurization tower to control the sulfur compound content to be 0.1 ppm or less; A step d of supplying hydrogen to the synthesis gas obtained from the previous step to adjust the composition of the synthesis gas so that the molar ratio of _{H 2} /(2CO+3CO _{2) is 0.9 to 1.1;} And an e step of compressing the syngas whose composition is adjusted to 40 to 100 atmospheres and reacting in a methanol reactor to produce methanol.

Hereinafter, the present invention will be described in more detail.

The method for producing methanol from carbon dioxide-containing methane gas according to the present invention,

A first step of partially removing hydrogen sulfide contained in methane gas containing carbon dioxide;

A second step of producing a synthesis gas by a dry reforming reaction using plasma from the carbon dioxide-containing methane gas obtained from the previous step;

A third step of supplying hydrogen to the synthesis gas obtained from the previous step to control the composition of the synthesis gas; And

It may include; a fourth step of preparing methanol from the syngas whose composition is adjusted.

Methane gas containing a large amount of carbon dioxide is typical of landfill gas and biogas. Usually, methane and carbon dioxide, which are the main components of landfill gas or biogas, are generated in concentrations of 40 to 70% by volume and 30 to 60% by volume, respectively, but the degree varies from time to time depending on conditions such as the source, time and/or season, and the extent of change is severe. It's a side.

Meanwhile, these gases mainly contain sulfur compounds as impurities, and further contain ammonia, volatile organic compounds (VOC), and siloxanes. Most of the sulfur compounds are hydrogen sulfide (H ₂ S), but may include some compounds of mercaptans or organic sulfides.

Most of these impurities can act as catalyst poisons that reduce the activity of the catalyst in the catalytic reaction, so strict control (<0.1 ppm) is required in the process including the catalytic reaction. Therefore, various methods have been performed to remove these impurities. For example, in the case of hydrogen sulfide, it is possible to relatively simply lower it to a certain level or lower in a large amount by using an iron oxide-based chemical adsorbent. However, in addition, substances such as VOC, siloxane, mercaptans, sulfides and amines are difficult to remove due to chemical adsorption, so they are removed using physical adsorbents such as activated carbon. Since it is used or requires frequent replacement, a considerable cost is required for this pretreatment.

Accordingly, the present invention is designed to simplify the process by minimizing the pretreatment process in producing methanol from landfill gas or biogas.

Accordingly, the methanol production method of the present invention may include removing only some hydrogen sulfide from the raw material gas, that is, carbon dioxide-containing methane gas, and producing a synthesis gas by a dry reforming reaction using plasma without a process of controlling a separate composition. .

The carbon dioxide-containing methane gas that can be used as a raw material gas in the methanol production method of the present invention may have a carbon dioxide content of 30% or more based on the number of moles of the dry gas of methane.

For example, the carbon dioxide-containing methane gas may contain 500 ppm or more of one or more impurities selected from the group consisting of hydrogen sulfide, volatile organic compounds, mercaptan compounds, ammonia, sulfide compounds, and siloxanes.

Furthermore, the carbon dioxide-containing methane gas may be a landfill gas or biogas.

In the methanol production method of the present invention, the content of hydrogen sulfide contained in the carbon dioxide-containing methane gas may be reduced to 50 ppm or less by removing some hydrogen sulfide by the first step.

The first step may be performed by using iron oxide or iron hydroxide as an adsorbent as follows, and using a fixed dry adsorption tower that is simple and economical in a small scale, but is not limited thereto.

Fe ₂ O ₃ + 3H ₂ S --> Fe ₂ S ₃ + 3H ₂ O

2Fe(OH) ₃ + 3H ₂ S --> Fe ₂ S ₃ + 6H ₂ O

In the case of using the adsorption tower, since the components of the iron oxide or iron hydroxide filled therein may be dissolved by the moisture contained in the gas, it is preferable to remove moisture in the gas applied thereto in advance. In particular, since iron hydroxide has a high reaction rate with hydrogen sulfide and a high removal rate, it may be advantageous to use iron hydroxide as an adsorbent in a process requiring a high degree of desulfurization, but the selection of the adsorbent is not limited thereto.

The manufacturing method of the present invention is characterized by using a dry reforming reaction by plasma to perform the second step of producing syngas from methane gas containing carbon dioxide. For example, a landfill gas or biogas, which is a carbon dioxide-containing methane gas, has a low calorific value when burning directly, and has a problem of generating a large amount of air pollutants because it contains impurities such as sulfur compounds and ammonia. In addition, since the composition of the gas is not uniform, it may be difficult to supply constant heat due to problems such as boiler fluctuation when using waste heat through direct combustion. Therefore, the present invention promotes resource conversion to synthetic gas by converting these raw material gases into high-quality synthetic gas through dry reforming using plasma rather than directly burning them, and at the same time safely treats volatile organic compounds, etc., and There is an advantage that can greatly reduce the occurrence. Since this plasma reforming reaction is an endothermic reaction, plasma that is discharged or induced by using electricity as a heat source is used. Since the plasma generated at this time is advantageous in performing the reforming reaction in a small space due to its high energy density, it may be suitable as a technology using a small-scale gas source. In addition, since it is easy to drive the reaction and the time required for normal operation is short, it can be economical because it is suitable for utilizing electric energy derived from renewable energy. That is, the plasma reforming reaction has an economic and/or environmental advantage in that it is possible to use the intermittent peak power of renewable energy electricity, which is less utilized due to the disadvantage of intermittent power generation. For example, plasma discharge can be classified into low-temperature plasma and high-temperature plasma according to electron density and temperature. In the case of high-temperature plasma, since the high-density ionic state is maintained, the reactivity is very high and high concentration hydrogen can be produced. In addition, by using the plasma's own heat, it can be applied to a wide range of flow rates and gas properties with a quick start-up and response time of several seconds.

In the dry reforming reaction by the plasma, the conversion rate may be 80% or more in the case of methane and 70% or more in the case of carbon dioxide. Preferably, a conversion rate of 80% or more in the case of methane and 70% or more in the case of carbon dioxide may be exhibited, but is not limited thereto. In the above process, the conversion rate of methane may be maintained at 80% or more. For example, when the conversion rate of methane is 80% or less, methane remaining in the methanol synthesis process, which is a subsequent process, acts as an inert gas and may remain as a dilution gas. In the case of carbon dioxide, since it participates as a reactant during methanol synthesis, a strict limit on its conversion rate is not required, but it may be desirable to maintain it similar to methane since it may affect the methane conversion rate during the reforming reaction.

On the other hand, volatile organic compounds among impurities are synthesized gas, mercaptan compounds and sulfide compounds are hydrogen sulfide, ammonia is nitrogen and hydrogen, and siloxane by a second step performed at a high temperature using a dry reforming reaction by plasma. Since silver can be converted into silica particles, the production method of the present invention may not separately include the step of removing other impurities other than excluding hydrogen sulfide prior to the second step of preparing the synthesis gas, so the methanol production method of the present invention Can be further simplified.

For example, the step of removing these substances in order to block particulate substances such as hydrogen sulfide and/or carbon particles or silica particles formed from impurities in the second step as described above inhibit the subsequent catalytic reaction. I can. For example, the 2-1 step of removing hydrogen sulfide from the synthesis gas generated by the dry reforming reaction after the second step, the 2-2 step of removing solid by-products by filtering, or both of the above two steps may be further included. However, it is not limited thereto. The step 2-1 may be performed by passing through a tower filled with an iron-based dry adsorbent, and step 2-2 may be performed by simply filtration by attaching a filter to the rear end of the reactor, but the method of performing the method is not limited thereto, Various methods known in the art can be used without limitation. The synthesis gas obtained through the above process may have a concentration of hydrogen sulfide adjusted to a level of 0.1 ppm or less, which is a level required for a catalytic reaction.

Specifically, the 2-1 step is performed to remove the residual hydrogen sulfide that has not been treated from the first step and the hydrogen sulfide formed from the organic sulfur compound during the reforming reaction of the second step. Similar to the step, it may be performed using an adsorption process, but is not limited thereto. At this time, as the adsorbent, iron or zinc-based compounds such as iron oxide, iron hydroxide, or zinc oxide may be used. For example, iron oxide or iron hydroxide capable of efficient chemical adsorption at a lower reaction temperature may be used, but is not limited thereto.

In addition, in general, the dry reforming reaction involves the formation of coke, and when the content of carbon dioxide, which is an oxidizing agent, is small, the formation of coke increases. In this case, when the carbon dioxide content is high, the reaction of the above-described equation 2) occurs predominantly, resulting in less coke generation, whereas when the carbon dioxide content is low, the methane pyrolysis reaction of equation 4) occurs and the coke generation increases. However, coke, which is such a particulate impurity, may be removed by filtration in the second step.

On the other hand, for the economical efficiency of the process, hydrogen supplied to the third step in the manufacturing method of the present invention may be produced by electrolysis of water, and the electrolysis of water may be performed using electric energy derived from renewable energy. , Is not limited thereto.

Further, by supplying hydrogen as described above, the composition of the synthesis gas in the third step may be adjusted so that the molar ratio _{of H 2} /(2CO+3CO _{2) is 0.9 to 1.1.}

As shown in the above formulas 5) and 6), CO and CO ₂ may react with 2 times and 3 times the number of moles of H ₂ , respectively, to produce methanol. Therefore, for an efficient reaction, _{the molar ratio of H 2} /(2CO+3CO ₂ ) in the syngas can be adjusted to be close to 1, for example, 0.9 to 1.1. For example, when the composition of the syngas is less than the above ratio, unreacted CO and CO ₂ remain, so there may be a trouble of continuously venting to prevent these gases from accumulating in the reaction system. For example, if these gases are not discharged and remain, energy efficiency may decrease in the entire reaction process. On the other hand, when the composition of the syngas exceeds the above ratio, it may be necessary to discharge excess hydrogen for efficiency of the reaction.

Therefore, in the reaction of synthesizing methanol from landfill gas or biogas with a carbon dioxide content of 30% or more of the total gas, since the methane reforming reaction is performed under excess carbon dioxide, hydrogen may become insufficient. Can supply.

The supplied hydrogen source may be hydrogen produced by electrolysis of water using renewable energy-based electricity, but is not limited thereto.

In the production method of the present invention, the fourth step of preparing methanol from the synthesis gas whose composition is adjusted may be carried out by a catalytic reaction using a methanol synthesis catalyst. Specifically, the fourth step may be achieved by a complex reaction of the above-described equations 5) to 7). At this time, the syngas may be compressed and increased to 40 to 100 atm and then injected into the reactor, but is not limited thereto. For example, the step of preparing methanol may be performed while syngas having a controlled composition passes through a fixed bed reactor filled with a methanol synthesis catalyst. For example, in the above process, three reactions of Equations 5) to 7) may occur simultaneously, but are not limited thereto.

For example, as a catalyst for methanol synthesis, a Cu/ZnO/Al ₂ O ₃ catalyst widely used in the art may be used. Specifically, a catalyst of 60% by weight Cu/30% by weight ZnO/10% by weight Al ₂ O ₃ may be used, but is not limited thereto.

Specifically, the methanol synthesis reaction may be performed under conditions of a reaction temperature of 240 to 270°C, a reaction pressure of 40 to 100 bar, and a space velocity of 1,000 to 50,000/h, but is not limited thereto. As shown in Equations 5) and 6), since the reaction to generate methanol is an exothermic reaction, the heat of reaction can be controlled to increase the yield of methanol. Specifically, the methanol synthesis reaction is an equilibrium reaction, and as the temperature of the reactor increases due to heat generated as the reaction proceeds, the equilibrium conversion rate of the reactant may decrease, so it is necessary to control the temperature in the reactor. For example, for this purpose, the heat of reaction may be controlled using latent heat by vaporization of water by flowing water as a refrigerant outside a tube in which the catalyst layer of the methanol synthesis reactor is located, but is not limited thereto.

As described above, the product formed while passing through the methanol synthesis reactor is cooled to recover methanol as a liquid product by gas-liquid separation, and some unreacted synthesis gas maintained in the gas phase is discharged, and the remainder is pressurized and injected into the methanol reactor. It can be reused (recycle) in the synthesis reaction, but is not limited thereto.

Furthermore, the method for producing methanol from landfill gas or biogas according to the present invention,

Step a of dehumidifying and partial desulfurization by pre-treating the landfill gas or biogas;

A step b of preparing a syngas by a dry reforming reaction using plasma at a pressure of 0.1 to 5 atmospheres of the pretreated gas obtained from the previous step;

A step c of cooling the synthesis gas obtained from the previous step to 0 to 50°C, filtering to remove particulate impurities, and then passing through a dry desulfurization tower to control the sulfur compound content to be 0.1 ppm or less;

A step d of supplying hydrogen to the synthesis gas obtained from the previous step to adjust the composition of the synthesis gas so that the molar ratio of _{H 2} /(2CO+3CO _{2) is 0.9 to 1.1;} And

It may include; step e of compressing the syngas whose composition is adjusted to 40 to 100 atmospheres and reacting in a methanol reactor to produce methanol.

For example, hydrogen supplied in step d may be produced by electrolysis of water.

In the above manufacturing method, the step b of performing the dry reforming reaction by plasma, the production of hydrogen to be supplied to the step d, or both may be performed using electric energy derived from renewable energy, but is not limited thereto.

Further, in the production method of the present invention, the synthesis gas produced as an intermediate by a dry reforming reaction by plasma from carbon dioxide-containing methane gas, such as a landfill gas or biogas, is not only for the synthesis of methanol, but also for the production of hydrogen, the production of ammonia, Alternatively, it may be used as a raw material in a synthetic oil manufacturing process by a Fischer-Tropsch reaction.

The methanol production process of the present invention is an effective method of producing methanol by converting a landfill gas or biogas having a high carbon dioxide content by including a carbon dioxide dry reforming reaction of methane by plasma. In addition, the present invention does not require a separate carbon dioxide removal process for controlling the content of carbon dioxide, and uses hydrogen generated based on renewable energy, so carbon efficiency is high, and a separate process for removing various impurities included in the source gas Since plasma pyrolysis can be performed without the process of, a simplified method for preparing methanol is provided.

1 is a diagram schematically showing a process for producing methanol from landfill gas or biogas.

Hereinafter, the present invention will be described in detail based on examples, but the present invention is not limited by the following examples.

Referring to FIG. 1, which is an embodiment of the present invention, a process for producing syngas from landfill gas or biogas is as follows.

First, the landfill gas or biogas is pretreated to dehumidify and desulfurize. In general, since the raw material gas contains 500 ppm or more of a sulfur component, a gas having a sulfur content of 50 ppm or less was obtained by primary desulfurization using a fixed dry adsorption tower filled with iron oxide or iron hydroxide as an adsorbent. Meanwhile, during the desulfurization process, moisture in the gas was removed in advance so that the iron oxide or iron hydroxide component was not dissolved by the moisture contained in the landfill gas or biogas.

The first pretreated gas as described above was passed through the plasma generating tube. The plasma generating tube is a layer in which a plasma induction coil is wound around an outer wall of a quartz tube, and a boron nitride (BN) tube is mounted therein. Synthetic gas was prepared by performing a reforming reaction while passing a gas containing methane and carbon dioxide through a plasma dry reformer equipped with a plasma layer, and various impurities contained in the raw material gas were decomposed at the same time as the reforming reaction.

After cooling the synthesis gas prepared in the previous step to 0 ~ 50 ℃, filtered through a bag filter (bag filter) mounted at the rear end of the reactor to remove the coke or siloxane-derived silica particles partially generated during the plasma reaction. Furthermore, the sulfur content was controlled to 0.1 ppm or less by passing the obtained synthesis gas through a secondary desulfurization adsorption tower. At this time, the desulfurization adsorption tower was provided with iron hydroxide having excellent desulfurization performance at room temperature as an adsorbent.

The post-treated syngas may be used as a raw material for a synthetic oil production process by methanol synthesis, hydrogen production, ammonia production, or Fischer-Tropsch reaction.

For example, in order to synthesize methanol from the syngas, it is necessary to additionally adjust the composition of the syngas. In the case of dry reforming of methane having a high carbon dioxide content, the H ₂ /(2CO+3CO ₂ ) molar ratio is about 0.3 to 0.8, so it is preferable to adjust the ratio to about 0.9 to 1.1 by supplying additional hydrogen for a more efficient reaction. . Hydrogen produced by using economical electric energy based on renewable energy can be used as the supplied hydrogen.

The synthesis gas whose composition is controlled as described above is compressed to 40 to 100 atm, and a fixed bed reactor at 240 to 270°C is filled with a methanol synthesis catalyst of _{60% by weight Cu/30% by weight ZnO/10% by weight of Al 2} O _{3 to 1,000.} Methanol was formed from the syngas while passing at a space velocity of ~ 50,000 h ^-1. After cooling the product passing through the methanol synthesis reactor to 0 ~ 50℃, gas-liquid separation is performed to obtain methanol as a liquid product, and some unreacted synthetic gas in the gas phase is discharged and the rest is pressurized and recycled to the methanol reactor. Made it.

Claims (13)

In the method for producing methanol from carbon dioxide-containing methane gas,
A first step of partially removing hydrogen sulfide contained in methane gas containing carbon dioxide;
A second step of producing a synthesis gas by a dry reforming reaction using plasma from the carbon dioxide-containing methane gas obtained from the previous step;
A third step of supplying hydrogen to the synthesis gas obtained from the previous step to control the composition of the synthesis gas; And
A fourth step of preparing methanol from the syngas whose composition is adjusted;
Methanol production method comprising a.
The method of claim 1, wherein the second step does not require a separate gas composition control.
The method of claim 1, wherein the carbon dioxide-containing methane gas has a carbon dioxide content of 30% or more based on the number of moles of dry gas of the methane.
The method of claim 1, wherein the carbon dioxide-containing methane gas contains 500 ppm or more of at least one impurity selected from the group consisting of hydrogen sulfide, volatile organic compounds, mercaptan compounds, ammonia, sulfide compounds, and siloxanes. .
The method of claim 1, wherein the carbon dioxide-containing methane gas is a landfill gas or biogas.
The method of claim 1, wherein the content of hydrogen sulfide contained in the carbon dioxide-containing methane gas is reduced to 50 ppm or less by the first step.
The method of claim 4, wherein the volatile organic compounds among impurities are converted into syngas, mercaptan compounds and sulfide compounds into hydrogen sulfide, ammonia into nitrogen and hydrogen, and siloxane into silica particles by the second step. Manufacturing method.
According to claim 7, After the second step, the 2-1 step of removing hydrogen sulfide from the synthesis gas generated by the dry reforming reaction, the 2-2 step of removing solid by-products by filtration, or both of the two steps are performed. It will further include, methanol production method.
The method of claim 1, wherein the hydrogen supplied in the third step is produced by electrolysis of water.
The method of claim 1, wherein the composition of the synthesis gas in the third step is adjusted so that the molar ratio _{of H 2} /(2CO+3CO _{2) is 0.9 to 1.1.}
In the method for producing methanol from landfill gas or biogas,
Step a of dehumidifying and partial desulfurization by pre-treating the landfill gas or biogas;
A step b of preparing a syngas by a dry reforming reaction using plasma at a pressure of 0.1 to 5 atmospheres of the pretreated gas obtained from the previous step;
A step c of cooling the synthesis gas obtained from the previous step at 0 to 50°C, filtering to remove particulate impurities, and then passing through a dry desulfurization tower to control the sulfur compound content to be 0.1 ppm or less;
A step d of supplying hydrogen to the synthesis gas obtained from the previous step to adjust the composition of the synthesis gas so that the molar ratio of _{H 2} /(2CO+3CO _{2) is 0.9 to 1.1;} And
E step of compressing the syngas whose composition is adjusted to 40 to 100 atmospheres and reacting in a methanol reactor to produce methanol;
Methanol production method comprising a.
The method of claim 11, wherein the hydrogen supplied in step d is produced by electrolysis of water.
The method of claim 11 or 12, wherein step b, step d, or both are performed using electric energy derived from renewable energy.

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