In at least one aspect, the present invention is related to direct methane to methanol and syngas to hydrogen.
Autothermal and steam reforming of natural gas are currently two of the most expensive methods of producing hydrogen and carbon oxides. The gaseous mixture of hydrogen and carbon oxides (carbon monoxide) is hereinafter referred to as “synthetic gas” or “syngas.” Syngas is useful as an intermediate for the manufacture of products such as hydrogen, ammonia, methanol or synthetic fuels. Currently, commercial methanol production is almost entirely based on reforming light hydrocarbons, especially methane, first to syngas, followed by syngas clean up, methanol synthesis, and methanol separation. This process has been the dominant route of methanol production since the 1920's. The entire process, however, is cumbersome with a high degree of complexity and associated costs. Therefore, a direct method has been developed using direct homogenous partial oxidation of methane to methanol (the “DHPO” method).
The DHPO method is, however generally limited by the need to balance high conversions and high selectivity to obtain the highest economic yields of methanol. In both catalytic and non-catalytic DHPO methods, the conversion process tends to create the co-products of aldehydes, alcohols, hydrogen, carbon oxides, and water.
Accordingly, there is a need for methods and apparatuses that can economically produce low cost methanol, synthesis gas and hydrogen.
In at least one aspect, a method for preparing oxygenated hydrocarbons is provided. The method includes a step of combining a hydrocarbon feed gas stream and a recycle gas stream to form a first hydrocarbon-containing gas stream. The hydrocarbon feed gas stream is characterized by a first temperature T1, the recycle gas stream is characterized by a second temperature T2, and the first hydrocarbon-containing gas stream is characterized by a third temperature T3. The first hydrocarbon-containing gas stream is preheated to form a second hydrocarbon-containing gas stream having a fourth temperature T4 that is greater than the third temperature T3. The second hydrocarbon-containing gas stream is reacted with an oxygen-containing gas stream in a partial oxidation reactor to form a first product stream. One or more liquid oxygenated hydrocarbons are separated and condensed from the first product stream. A fuel gas stream and the recycle gas stream are separated from the first product stream. A portion of the first hydrocarbon-containing gas stream and the second hydrocarbon-containing gas stream are combined to form a third hydrocarbon-containing gas stream having a fifth temperature that is between the third temperature and the fourth temperature. The third hydrocarbon-containing gas stream and oxygen are directed to a syngas reactor that converts the third hydrocarbon-containing gas stream to syngas and/or turquoise hydrogen. Finally, syngas and/or turquoise hydrogen is collected from the syngas reactor.
In another aspect, a method for preparing oxygenated hydrocarbons is provided. The method includes a step of combining a hydrocarbon feed gas stream and a CO2 lean recycle gas stream to form a first hydrocarbon-containing gas stream. The hydrocarbon feed gas stream is characterized by a first temperature T1, the CO2 lean recycle gas stream is characterized by a second temperature T2, and the first hydrocarbon-containing gas stream is characterized by a third temperature T2. The first hydrocarbon-containing gas stream is preheated to form a second hydrocarbon-containing gas stream having a fourth temperature T4 that is greater than the third temperature T3. The second hydrocarbon-containing gas stream is reacted with a first oxygen-containing gas stream in a GTL reactor to form a first product stream. One or more liquid oxygenated hydrocarbons are separated and condensed from the first product stream. A fuel gas stream and a CO2 rich recycle gas stream are separated from the first product stream. CO2 is removed from the CO2 rich recycle gas stream to form the CO2 lean recycle gas stream. A portion of the CO2 lean recycle gas stream is combined with a portion of the fuel gas stream to form a third hydrocarbon-containing gas stream. The third hydrocarbon-containing gas stream and a second oxygen-containing stream is directed to a syngas reactor (e.g., a DRM reactor) to form syngas and/or turquoise hydrogen. Finally, syngas is collected from the syngas reactor and/or turquoise hydrogen.
In another aspect, a combined POX and methanol forming system is provided. Advantages of a combined POX and MeOH system include: a major saving on CAPEX as combined process eliminates the need for a separate ASU; syngas production becomes significantly cheaper compared to a convention reforming process; GTL oxygen production is easily scalable to the POM feed requirements; downstream compatible syngas for FT; Diesel/gasoline or MeOH; Heat integration of the POX reactor also offers additional savings on the distillation of GTL products, and easily integrated to the MiniGTL plant with minimal utility requirement.
In another aspect, a system for producing syngas and/or turquoise hydrogen applying the methods herein is provided. The system includes a hydrocarbon feed gas stream source that provides hydrocarbon feed gas stream where the hydrocarbon feed gas stream has a first temperature and a recycle conduit through which a recycle gas stream flows where the recycle gas stream having a second temperature. A heating component preheats a first hydrocarbon-containing gas stream having a third temperature to form a second hydrocarbon-containing gas stream having a fourth temperature that is greater than the third temperature. The first hydrocarbon-containing gas stream includes a component selected from the group consisting of the hydrocarbon feed gas stream, the recycle gas stream, and combinations thereof. The system also includes a partial oxidation reactor for reacting the second hydrocarbon-containing gas stream with a first oxygen-containing gas stream to form a first product stream. The system also includes a 2-phase separator that separates and condenses one or more liquid oxygenated hydrocarbons from the first product stream. Advantageously, the 2-phase separator also separates a fuel gas stream and the recycle gas stream from the first product stream. A syngas reactor (e.g., a DRM reactor) receives a third hydrocarbon-containing gas stream and a second oxygen-containing gas stream. Characteristically, the syngas reactor converts the third hydrocarbon-containing gas stream to syngas and/or turquoise hydrogen, the third hydrocarbon-containing gas stream including a component selected from the group consisting of a portion of the first hydrocarbon-containing gas stream, a portion of the second hydrocarbon-containing gas stream, and combinations thereof where the third hydrocarbon-containing gas stream having a fifth temperature that is between the third temperature and the fourth temperature.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
For a further understanding of the nature, objects, and advantages of the present disclosure, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
Reference will now be made in detail to presently preferred compositions, embodiments and methods of the present invention, which constitute the best modes of practicing the invention presently known to the inventors. The Figures are not necessarily to scale. However, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for any aspect of the invention and/or as a representative basis for teaching one skilled in the art to variously employ the present invention.
Except in the examples, or where otherwise expressly indicated, all numerical quantities in this description indicating amounts of material or conditions of reaction and/or use are to be understood as modified by the word “about” in describing the broadest scope of the invention. Practice within the numerical limits stated is generally preferred. Also, unless expressly stated to the contrary: percent, “parts of,” and ratio values are by weight; the description of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures of any two or more of the members of the group or class are equally suitable or preferred; description of constituents in chemical terms refers to the constituents at the time of addition to any combination specified in the description, and does not necessarily preclude chemical interactions among the constituents of a mixture once mixed; the first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation; and, unless expressly stated to the contrary, measurement of a property is determined by the same technique as previously or later referenced for the same property.
Except in the examples, or where otherwise expressly indicated, all numerical quantities in this description indicating amounts of material or conditions of reaction and/or use are to be understood as modified by the word “about” in describing the broadest scope of the invention. Practice within the numerical limits stated is generally preferred. Also, unless expressly stated to the contrary: percent, “parts of,” and ratio values are by weight; the description of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures of any two or more of the members of the group or class are equally suitable or preferred; description of constituents in chemical terms refers to the constituents at the time of addition to any combination specified in the description, and does not necessarily preclude chemical interactions among the constituents of a mixture once mixed; the first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation; and, unless expressly stated to the contrary, measurement of a property is determined by the same technique as previously or later referenced for the same property.
It must also be noted that, as used in the specification and the appended claims, the singular form “a,” “an,” and “the” comprise plural referents unless the context clearly indicates otherwise. For example, reference to a component in the singular is intended to comprise a plurality of components.
As used herein, the term “about” means that the amount or value in question may be the specific value designated or some other value in its neighborhood. Generally, the term “about” denoting a certain value is intended to denote a range within +/−5% of the value. As one example, the phrase “about 100” denotes a range of 100+/−5, i.e. the range from 95 to 105. Generally, when the term “about” is used, it can be expected that similar results or effects according to the invention can be obtained within a range of +/−5% of the indicated value.
As used herein, the term “and/or” means that either all or only one of the elements of said group may be present. For example, “A and/or B” shall mean “only A, or only B, or both A and B”. In the case of “only A”, the term also covers the possibility that B is absent. i.e. “only A, but not B”.
It is also to be understood that this invention is not limited to the specific embodiments and methods described below, as specific components and/or conditions may, of course, vary. Furthermore, the terminology used herein is used only for the purpose of describing particular embodiments of the present invention and is not intended to be limiting in any way.
The term “comprising” is synonymous with “including,” “having,” “containing,” or “characterized by.” These terms are inclusive and open-ended and do not exclude additional, unrecited elements or method steps.
The phrase “consisting of” excludes any element, step, or ingredient not specified in the claim. When this phrase appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole.
The phrase “consisting essentially of” limits the scope of a claim to the specified materials or steps, plus those that do not materially affect the basic and novel characteristic(s) of the claimed subject matter.
The phrase “composed of” means “including” or “consisting of.” Typically, this phrase is used to denote that an object is formed from a material.
With respect to the terms “comprising,” “consisting of,” and “consisting essentially of,” where one of these three terms is used herein, the presently disclosed and claimed subject matter can include the use of either of the other two terms.
The term “one or more” means “at least one” and the term “at least one” means “one or more.” The terms “one or more” and “at least one” include “plurality” as a subset.
The term “substantially,” “generally,” or “about” may be used herein to describe disclosed or claimed embodiments. The term “substantially” may modify a value or relative characteristic disclosed or claimed in the present disclosure. In such instances, “substantially” may signify that the value or relative characteristic it modifies is within ±0%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5% or 10% of the value or relative characteristic.
It should also be appreciated that integer ranges explicitly include all intervening integers. For example, the integer range 1-10 explicitly includes 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Similarly, the range 1 to 100 includes 1, 2, 3, 4 . . . 97, 98, 99, 100. Similarly, when any range is called for, intervening numbers that are increments of the difference between the upper limit and the lower limit divided by 10 can be taken as alternative upper or lower limits. For example, if the range is 1.1. to 2.1 the following numbers 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 can be selected as lower or upper limits.
In the examples set forth herein, concentrations, temperature, flow rates, and reaction conditions (e.g., pressure, pH, flow rates, etc.) can be practiced with plus or minus 50 percent of the values indicated rounded to or truncated to two significant figures of the value provided in the examples. In a refinement, concentrations, temperature, flow rates and reaction conditions (e.g., pressure, pH, flow rates, etc.) can be practiced with plus or minus 30 percent of the values indicated rounded to or truncated to two significant figures of the value provided in the examples. In another refinement, concentrations, temperature, flow rates, and reaction conditions (e.g., pressure, pH, flow rates, etc.) can be practiced with plus or minus 10 percent of the values indicated rounded to or truncated to two significant figures of the value provided in the examples.
With respect to
Referring to
With reference to
Sill referring to
A first substream 36 of second hydrocarbon-containing gas stream 34 is introduced into GLT reactor 40 (a type of partial oxidation reactor) with an oxygen-containing gas stream 38 form a first product stream 44.
In a variation, each of first hydrocarbon-containing gas stream 26, second hydrocarbon-containing gas stream 34, third hydrocarbon-containing gas stream 56, and substreams thereof each independently include C1-10 alkanes. Examples of such alkanes include but are not limited to methane, ethane, propanes, butanes, pentanes, and combinations thereof.
Still referring to
CH4+½O2×CO+2H2 ΔH298=−8.5 kcal/mol
It should be appreciated that this a catalytic process (Ni is a most active catalyst for this reaction).
In another embodiment, a gaseous composition that is provided to a POX syngas reactor is provided. The gaseous composition includes methane in a mole fraction from 0.65 to 0.8, ethane in a mole fraction from 0.1 to 0.3, propane in a mole fraction from 0.01 to 0.1, carbon dioxide in a mole fraction from 0.001 to 0.05, carbon monoxide in a mole fraction from 0.001 to 0.05, nitrogen in a mole fraction from 0.02 to 0.13, and hydrogen in a mole fraction from 0.001 to 0.05.
With reference to
Still referring to
Second hydrocarbon-containing gas stream 134 is combined with a second substream 135 of first hydrocarbon-containing gas stream 126 to form third hydrocarbon-containing gas stream 136. Since second substream 135 of first hydrocarbon-containing gas stream 126 has a lower temperature than second hydrocarbon-containing gas stream 314, second substream 135 can be used to low the temperature of second hydrocarbon-containing gas stream 34 when needed. Third hydrocarbon-containing gas stream 136 is introduced into GLT reactor 140 (a type of partial oxidation reactor) with an oxygen-containing gas stream 138 form a first product stream 144.
In a refinement, one or more liquid oxygenated hydrocarbons (e.g., methanol, ethanol, etc.) are separated from the first product stream 144. In a refinement, the first product stream includes an alcohol selected from the group consisting of methanol, ethanol, propanols, butanols, pentanols and combinations thereof. Advantageously, these liquid oxygenated hydrocarbons are collected for commercial applications. In a refinement, first product stream 144 passes through heat exchanger 130 to provide the preheating of the first hydrocarbon-containing gas stream 126. In a refinement, this separation is accomplished using 2-phase separator 128. A fuel gas stream 148 and a CO2-rich gas stream 150 are obtained from the first product stream. Typically, fuel gas stream 148 and the CO2-rich gas stream 150 have the same chemical compositions. Three-way valve or flow splitter 152 are used to separate the fuel gas stream 148 and a CO2-rich gas stream 150. Advantageously, fuel gas stream 148 can be collected for commercial applications. CO2-rich gas stream 150 is directed to CO2 stripper 160 to form recycle CO2-lean gas stream 122 and CO2 stream 162 which can be collected for commercial applications. Recycle CO2-lean gas stream 122 includes hydrocarbons such as methane, ethane, etc. CO2 stream 162 or a substream thereof and fuel gas stream 148 or a substream thereof are directed to syngas reactor 170 that is used to form syngas. In a refinement, syngas reactor 170, which is dry methane reforming (DMR) reactor that form syngas according to the following equation
CH4+CO2⇄2H2+2CO ΔH298 K0=+247 kj/mol
It should be appreciated that this a catalytic process (Ni is a most active catalyst for this reaction).
In another embodiment, the CO produced from the syngas reactor (e.g., a DRM reactor and/or a POX reactor) can be used in a blast furnace either directly transporting the gas through a pipeline or by filled compressed cylinders. The iron ores such as haematite contain iron (III) oxide, Fe 203, which can be reduced to metallic iron by an iron ore reduction process to produce pig iron for construction:
Iron (III) oxide+carbon monoxide→iron+carbon dioxide Fe2O3(s)+3CO(s)→2Fe(l)+3CO2(g)
The hot stream of CO coming out of the syngas reactor (e.g., a DRM reactor and/or a POX reactor) can be feed in to the blast furnace and the temperature of the CO stream can be in the range of 200-800° C. Iron oxide will partially reduce to Fe (III, II and oxides) at around 700-1200° C. the oxides will be reduced to pure metallic iron, commonly known as pig iron.
In a refinement, heat integration of the blast furnace with the GTL reactor, DRM and POX reactor will bring additional saving on the energy utilization and reduce overall CO2 emission of the plant.
This CO2 produced in the process can be recycled back in the syngas reactor (e.g., the DRM reactor) for producing CO and hydrogen. Consuming a portion of the CO from the syngas stream of the syngas reactor (e.g., a DRM reactor and/or a POX reactor) will increase the H2/CO ratio to >2, which meets the downstream requirement of FT fuels and methanol production. The CO utilization of the DRM/POX reactor-produced syngas in a blast furnace may be used as a syngas ratio adjuster in the reforming process.
In another embodiment, a gaseous composition that is provided to a DRM syngas reactor is provided. The gaseous composition includes methane in a mole fraction from 0.35 to 0.5, ethane in a mole fraction from 0.05 to 0.2, propane in a mole fraction from 0.01 to 0.1, carbon dioxide in a mole fraction from 0.3 to 0.06, carbon monoxide in a mole fraction from 0.005 to 0.05, nitrogen in a mole fraction from 0.005 to 0.05, and hydrogen in a mole fraction from 0.01 to 0.05.
In a variation of system 10 of
In a variation, a blast furnace 90 can be used as a syngas ratio adjuster for the partial oxidation reactor (e.g., a DRM or POX reactor). In a refinement, a syngas ratio of CO:H2 is adjusted from 1:1 to 1:2 using the blast furnace downstream of the syngas reactor.
In a variation, the output gas from nitrogen removal system 232 is received by reciprocating compressor 234, which after compression is passed to GLT plant 236 where it is reacted with oxygen from an oxygen source 238 as set forth above. In a refinement, GTL plant can output a product blend 240. GTL plant 236 can be the GLT system set forth in U.S. Pat. No. 9,255,051; the entire disclosure of which is hereby incorporated by reference.
The product blend 240 advantageously includes methanol and ethanol. In a refinement, the product blend can also include hydrogen (H2), acetone, dimethyl ether, isopropanol, acetic acid, formic acid, formaldehyde, dimethoxymethane, 1,1 dimethoxyethane, methyl formate, methyl acetate, and water. In another refinement, product blend includes 0 to 15 mole percent acetone, 30 to 99 mole percent methanol, 0 to 20 mole percent ethanol, 0.0 to 10 mole percent isopropanol, 0 to 1 mole percent acetic acid, 0 to 1 mole percent formic acid, 0 to 15 mole percent formaldehyde, and 1 to 30 mole percent water.
Advantageously, the integrated system of
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention
This application claims the benefit of U.S. provisional application Ser. No. 63/049,883 filed Jul. 9, 2020, the disclosure of which is hereby incorporated in its entirety by reference herein.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/041121 | 7/9/2021 | WO |
Number | Date | Country | |
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63049883 | Jul 2020 | US |