An integrated indirect heat transfer method for producing syngas and olefins through catalytic partial oxidation and cracking.

Abstract

A method for producing synthesis gas and olefins, the method comprising: feeding a catalytic partial oxidation (CPO) reactant mixture comprising oxygen, a first hydrocarbon and optionally steam to a CPO reaction zone comprising a CPO catalyst, such that at least a portion of the CPO reactant mixture reacts by an exothermic CPO reaction to produce a synthesis gas comprising hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water and unreacted first hydrocarbon, wherein the synthesis gas is characterized by a molar ratio M defined as (H2-CO2) / (CO+CO2); feeding a cracking zone feed comprising a second hydrocarbon to the cracking zone, such that at least a portion of the second hydrocarbon undergoes an endothermic cracking reaction to produce a cracking zone product stream comprising olefins, hydrogen and unreacted second hydrocarbon; and cooling the CPO reaction zone by heating the cracking zone while cooling the CPO reaction zone by heat transfer between the CPO reaction zone and the cracking zone.

Description

Technical Field

[0001] The present disclosure relates to a process for producing methanol, and more particularly, to a process for producing methanol from synthesis gas produced by catalytic partial oxidation (CPO) of hydrocarbons (eg, methane) integrated with cracking such that at least a portion of the heat required for cracking is provided by CPO. Background Art

[0002] Syngas is a mixture containing carbon monoxide (CO) and hydrogen (H2) and a small amount of carbon dioxide (CO2), water (H2O) and unreacted methane (CH4). Syngas is commonly used as an intermediate in the production of methanol and ammonia, and is formed as an intermediate in synthetic petroleum used as a lubricant or fuel. Although other hydrocarbon sources, such as refinery exhaust, naphtha feedstock, heavy hydrocarbons, coal, biomass, etc. can be used for synthesis gas production, synthesis gas is usually produced by steam reforming of natural gas (steam methane reforming or SMR). SMR is an endothermic process that requires a large amount of energy input to drive the reaction forward. The hydrogen content of the synthesis gas produced by conventional endothermic technology such as SMR is higher than the content required for synthetic methanol. Typically, SMR produces synthesis gas with an M ratio in the range of 2.6 to 2.98, wherein the M ratio is defined as the molar ratio of (H2-CO2) / (CO+CO2).

[0003] In the autothermal reforming (ATR) process, part of the natural gas is burned as fuel to drive the conversion of natural gas into synthesis gas, resulting in a relatively low hydrogen concentration and a relatively high CO2 concentration. Conventional methanol production equipment utilizes combined reforming (CR) technology, which pairs SMR with autothermal reforming (ATR) to reduce the amount of hydrogen present in the synthesis gas. ATR produces synthesis gas with a hydrogen content lower than the content required for methanol synthesis. Typically, ATR produces synthesis gas with an M ratio in the range of 1.7 to 1.84. In CR technology, the natural gas feed volume flow rate of SMR and ATR can be adjusted to achieve a total synthesis gas M ratio of 2.0 to 2.06. In addition, the hydrogen content of CR synthesis gas is greater than the content required for methanol synthesis. Moreover, SMR is a highly endothermic process, and the endothermicity of SMR technology requires burning fuel to drive the synthesis of synthesis gas. Therefore, SMR technology reduces the energy efficiency of the methanol synthesis process.

[0004] Synthesis gas is also produced (non-commercially) by catalytic partial oxidation of natural gas (CPO or CPOx). The CPO process employs partial oxidation of a hydrocarbon feed to produce a synthesis gas comprising CO and H2. The CPO process is exothermic and therefore does not require external heat. However, the composition of the synthesis gas produced is not suitable for methanol synthesis, for example due to reduced hydrogen content. In addition, in the CPO process, it can be challenging to maintain the desired catalyst activity and productivity due to elevated or uncontrolled CPO temperatures that lead to catalyst deactivation. The CPO reaction is exothermic and can result in a high temperature rise of the CPO catalyst bed, which in turn can result in catalyst deactivation. Therefore, there is a continuing need to develop a CPO process for producing synthesis gas by managing the reaction temperature, and to produce synthesis gas suitable for a methanol production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] In order to describe in detail the preferred embodiments of the disclosed method, reference will now be made to the accompanying drawings, in which:

[0006] Figure 1 A schematic diagram of a system for a methanol production process is shown;

[0007] Figures 2A-2C a schematic diagram showing the arrangement of a CPO reaction zone and a cracking zone according to an embodiment of the present disclosure; and

[0008] Figure 3 A schematic diagram of a separation unit according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0009] Disclosed herein is a method for producing synthesis gas and olefins, comprising: (a) feeding a catalytic partial oxidation (CPO) reactant mixture to a CPO reaction zone; wherein the CPO reactant mixture comprises oxygen, a first hydrocarbon, and optionally steam; wherein at least a portion of the CPO reactant mixture reacts in the CPO reaction zone via an exothermic CPO reaction to produce synthesis gas; wherein the CPO reaction zone comprises a CPO catalyst; wherein the synthesis gas comprises hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water, and unreacted first hydrocarbon, and wherein the synthesis gas is characterized by an M ratio of the synthesis gas, wherein wherein the M ratio is defined as the molar ratio of (H2-CO2) / (CO+CO2); (b) feeding a cracking zone feed to the cracking zone, wherein the cracking zone feed comprises a second hydrocarbon; wherein at least a portion of the second hydrocarbon undergoes an endothermic cracking reaction in the cracking zone to produce a cracking zone product stream; wherein the first hydrocarbon and the second hydrocarbon are the same or different; wherein the cracking zone product stream comprises olefins, H2 and unreacted second hydrocarbon; and (c) cooling the CPO reaction zone; wherein cooling the CPO reaction zone comprises heating the cracking zone while cooling the CPO reaction zone by heat transfer (e.g., indirect heat transfer) between the CPO reaction zone and the cracking zone.

[0010] In some embodiments, the process may further include: (1) separating at least a portion of the cracking zone product stream into a hydrogen stream and a hydrocarbon stream, wherein the hydrocarbon stream comprises olefins and unreacted hydrocarbons; (2) optionally contacting at least a portion of the hydrogen stream with at least a portion of the synthesis gas to produce a hydrogen-enriched syngas, wherein the hydrogen-enriched syngas is characterized by an M ratio greater than the M ratio of the synthesis gas, and wherein the M ratio of the hydrogen-enriched syngas is equal to or greater than about 1.7; (3) optionally introducing at least a portion of the synthesis gas and / or at least a portion of the hydrogen-enriched syngas into a methanol reactor to produce methanol; (4) optionally separating at least a portion of the hydrocarbon stream into an olefin stream and an unreacted hydrocarbon stream, wherein the olefin stream comprises at least a portion of the olefins in the hydrocarbon stream, and wherein the unreacted hydrocarbon stream comprises at least a portion of the unreacted hydrocarbons in the hydrocarbon stream; and (5) optionally recycling at least a portion of the hydrocarbon stream and / or at least a portion of the unreacted hydrocarbon stream to the cracking zone in step (b) and / or the CPO reaction zone in step (a). The first hydrocarbon and / or the second hydrocarbon may include methane, ethane, propane, butane, naphtha, natural gas, natural gas liquids, associated gas, wellhead gas, enriched gas, paraffin, shale gas, shale liquids, fluidized catalytic cracking (FCC) tail gas, refinery process gas, flue gas, fuel gas from a fuel gas header, or a combination thereof. In an embodiment, the second hydrocarbon includes C2H6, propane, butane, naphtha, optionally CH4, or a combination thereof; and the olefin includes ethylene.

[0011] In order to adjust the H2 / CO molar ratio of the syngas to a value greater than about 1.7-1.9, the methods disclosed herein illustrate methods for increasing the H2 / CO molar ratio and / or reducing the hydrocarbon concentration (e.g., reducing methane slip) in the syngas. In one embodiment, a hydrogen stream having a hydrogen-rich content may be mixed with the CPO reaction zone effluent in any suitable ratio to provide a hydrogen-enriched syngas having a H2 / CO molar ratio greater than about 1.7, 1.8, 1.9, or 2.0. By utilizing heat from the exothermic CPO reaction in the CPO reaction zone to provide heat for endothermic cracking of the cracking zone feed in the cracking zone, escape temperatures in the CPO reaction zone may be avoided.

[0012] Except in the operating examples or when otherwise indicated, all numbers or expressions related to the amount of ingredients, reaction conditions, etc. used in the specification and claims should be understood to be modified by the term "about" in all cases. Various numerical ranges are disclosed herein. Because these ranges are continuous, they include each value between the minimum and maximum values. The endpoints of all ranges listing the same feature or component can be independently combined and include the listed endpoints. Unless otherwise explicitly stated, the various numerical ranges specified in this application are approximate values. The endpoints of all ranges for the same component or property include the endpoints and can be independently combined. The term "from greater than 0 to ... amount" refers to that the specified component exists in an amount greater than 0, and is up to and including a higher specified amount.

[0013] The terms "a", "an" and "the" do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. As used herein, the singular forms "a", "an" and "the" include plural referents.

[0014] As used herein, "a combination thereof" includes one or more of the recited elements, optionally including similar elements that are not recited, such as a combination including one or more specified components, optionally including one or more other components that are not specifically specified and have substantially the same function. As used herein, the term "combination" includes blends, mixtures, alloys, reaction products, and the like.

[0015] References throughout the specification to "one embodiment," "another embodiment," "other embodiments," "some embodiments," etc., mean that particular elements (e.g., features, structures, properties, and / or characteristics) described in conjunction with the embodiment are included in at least one embodiment described herein, and may or may not be present in other embodiments. Furthermore, it should be understood that the described elements may be combined in any suitable manner in the various embodiments.

[0016] As used herein, the terms "inhibit" or "reduce" or "prevent" or "avoid" or any variation of these terms includes any measurable amount of reduction or complete inhibition to achieve the desired result.

[0017] As used herein, the term "effective" means sufficient to achieve a desired, expected, or intended result.

[0018] As used herein, the terms "comprising" (and any form of comprising, such as "comprise" and "comprises"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include"), or "containing" (and any form of containing, such as "contains" and "contain") are inclusive or open-ended, and do not exclude additional, unrecited elements or method steps.

[0019] Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Standard nomenclature is used herein to describe compounds. For example, any position not substituted by any designated group is understood to have its valence filled by the designated bond or hydrogen atom. A hyphen ("-") that is not between two letters or symbols is used to indicate the point of attachment of a substituent. For example, -CHO is attached through the carbon of the carbonyl group. As used herein, the term "C x Hydrocarbons" and "C x " are interchangeable and refer to any hydrocarbon having x carbon atoms (C). For example, the terms "C4 hydrocarbon" and "C4" both refer to any hydrocarbon having exactly 4 carbon atoms, such as n-butane, isobutane, cyclobutane, 1-butene, 2-butene, isobutene, butadiene, etc. or combinations thereof. As used herein, the term "C x+ A "hydrocarbon" refers to any hydrocarbon having equal to or greater than x carbon atoms (C). For example, the term "C 2+ "Hydrocarbon" refers to any hydrocarbon having 2 or more carbon atoms, such as ethane, ethylene, C3, C4, C5, etc.

[0020] refer to Figure 1 , a methanol production system 1000 is disclosed. The methanol production system 1000 generally comprises a catalytic partial oxidation (CPO or CPOx) reaction zone 100; a methanol reactor 200; a gas-liquid separator 300; a distillation unit 400; a first hydrogen (H2) recovery unit 500; a cracking zone 600; and a separation unit including a second H2 recovery unit 700 and a separator 800. Common reference numerals refer to common components present in one or more of the figures, and the description of a particular component generally applies to each figure in which the component is present unless otherwise indicated herein.

[0021] In one embodiment, the method disclosed herein may include the step of reacting a CPO reactant mixture 10 in a CPO reaction zone 100 by a CPO reaction to produce a CPO reaction zone effluent comprising a syngas 15; wherein the CPO reactant mixture 10 comprises oxygen (O2), a hydrocarbon (e.g., a first hydrocarbon), and optionally steam; wherein the CPO reaction zone 100 comprises a CPO catalyst; and wherein the CPO reaction zone effluent (e.g., syngas 15) comprises hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water, and unreacted first hydrocarbon, and wherein the syngas is characterized by an M ratio of the syngas, wherein the M ratio is a molar ratio defined as (H2-CO2) / (CO+CO2). As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the composition of the resulting CPO reaction zone effluent (e.g., syngas 15) recovered from the CPO reaction zone 100 may vary depending on the composition of the CPO reactant mixture 10.

[0022] Generally, the CPO reaction is based on partial combustion of fuel (e.g., various hydrocarbons), and in the case of methane, CPO can be represented by reaction equation (1):

[0023] CH4+1 / 2O2→CO+2H2 (1)

[0024] Without wishing to be bound by theory, side reactions may occur with the CPO reaction described in reaction formula (1); and such side reactions may, for example, produce carbon dioxide (CO2) and water (H2O) by combustion of hydrocarbons, which is an exothermic reaction. As will be appreciated by those skilled in the art, with the aid of the present disclosure, and without wishing to be bound by theory, the CPO reaction represented by reaction formula (1) may produce a synthesis gas having a hydrogen to CO (H2 / CO) molar ratio of 2.0, which is the theoretical stoichiometric limit. Without wishing to be bound by theory, the theoretical stoichiometric limit of 2.0 for the H2 / CO molar ratio refers to the CPO reaction represented by reaction formula (1) producing 2 moles of H2 for every 1 mole of CO, i.e., a H2 / CO molar ratio of (2 moles of H2 / 1 mole of CO) = 2. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the theoretical stoichiometric limit of 2.0 for the H2 / CO molar ratio in the CPO reaction cannot actually be achieved because the reactants (e.g., hydrocarbons, O2) and the products (e.g., H2, CO) undergo side reactions under the conditions used for the CPO reaction. As will be appreciated by those skilled in the art, with the aid of this disclosure, and without wishing to be bound by theory, in the presence of O2, CO and H2 can be oxidized to CO2 and H2O, respectively. The relative amounts (e.g., composition) of CO, H2, CO2, and H2O can be further altered by the balance of the water-gas shift (WGS) reaction, which will be discussed in more detail below. Side reactions that may occur in the CPO reaction zone 100 can directly affect the M ratio of the produced syngas 15, where the M ratio is a molar ratio defined as (H2-CO2) / (CO+CO2). In the absence of any side reactions (theoretically), the CPO reaction represented by reaction equation (1) produces a syngas having an M ratio of 2.0. However, the presence of side reactions (actually) reduces H2 and increases CO2, thereby producing a syngas having an M ratio below 2.0.

[0025] Furthermore, without wishing to be bound by theory, the CPO reaction described in reaction equation (1) is an exothermic heterogeneous catalytic reaction (i.e., a mildly exothermic reaction), and it occurs in a single reactor unit, such as CPO reaction zone 100 (relative to more than one reactor unit in conventional methods of synthesis gas production (e.g., steam methane reforming (SMR)-autothermal reforming (ATR) combination)). Although partial oxidation of hydrocarbons can be carried out as a homogeneous reaction, in the absence of a catalyst, the homogeneous partial oxidation process of hydrocarbons results in excessively high temperatures, long residence times, and excessive coke formation, which strongly reduces the controllability of the partial oxidation reaction and may not produce the desired quality of synthesis gas in a single reaction zone. Moreover, without wishing to be bound by theory, the CPO reaction is fairly resistant to chemical poisoning, thereby allowing the use of a variety of hydrocarbon feedstocks, including some sulfur-containing hydrocarbon feedstocks; this can, in some cases, increase catalyst life and productivity. In contrast, conventional ATR processes have more stringent feed requirements, such as in terms of impurity content in the feed (e.g., the feed to the ATR is desulfurized) and hydrocarbon composition (e.g., the ATR uses primarily CH4-rich feedstock).

[0026] In one embodiment, hydrocarbons (e.g., first hydrocarbons) suitable for the CPO reaction disclosed herein may include methane (CH4), ethane, propane, butane, naphtha, natural gas, natural gas liquids, associated gas, wellhead gas, enriched gas, paraffin, shale gas, shale liquids, fluidized catalytic cracking (FCC) tail gas, refinery process gas, flue gas, fuel gas from a fuel gas header, etc. or combinations thereof. The hydrocarbons (e.g., first hydrocarbons) may include any suitable hydrocarbon source and may contain C1-C6 hydrocarbons as well as some heavier hydrocarbons.

[0027] In one embodiment, the CPO reactant mixture 10 may include natural gas. Typically, natural gas is primarily composed of methane, but may also contain ethane, propane, and heavier hydrocarbons (e.g., isobutane, n-butane, isopentane, n-pentane, hexane, etc.) and very small amounts of nitrogen (N2), O2, CO2, sulfur compounds, and / or water. Natural gas may be provided from a variety of sources, including but not limited to gas fields, oil fields, coal fields, shale fields, fracturing, biomass, landfill gas, etc., or a combination thereof. The CPO reactant mixture 10 may include CH4 and O2.

[0028] Natural gas can contain any suitable amount of methane. In some embodiments, natural gas can contain biogas. For example, natural gas can contain about 45mol% to about 80mol% methane, about 20mol% to about 55mol% CO2 and less than about 15mol% N2.

[0029] In one embodiment, the natural gas may contain CH4 in an amount equal to or greater than about 45 mol%, about 50 mol%, about 55 mol%, about 60 mol%, about 65 mol%, about 70 mol%, about 75 mol%, about 80 mol%, about 82 mol%, about 84 mol%, about 86 mol%, about 88 mol%, about 90 mol%, about 91 mol%, about 92 mol%, about 93 mol%, about 94 mol%, about 95 mol%, about 96 mol%, about 97 mol%, about 98 mol%, or about 99 mol%.

[0030] In some embodiments, hydrocarbons (e.g., first hydrocarbons) suitable for use in the CPO reaction disclosed herein may include C1-C6 hydrocarbons, nitrogen (e.g., from about 0.1 mol% to about 15 mol%, from about 0.5 mol% to about 11 mol%, from about 1 mol% to about 7.5 mol%, or from about 1.3 mol% to about 5.5 mol%), and CO2 (e.g., from about 0.1 mol% to about 2 mol%, from about 0.2 mol% to about 1 mol%, or from about 0.3 mol% to about 0.6 mol%). For example, hydrocarbons suitable for use in the CPO reactions disclosed herein (e.g., first hydrocarbons) may include C1 hydrocarbons (about 89 mol% to about 92 mol%); C2 hydrocarbons (about 2.5 mol% to about 4 mol%); C3 hydrocarbons (about 0.5 mol% to about 1.4 mol%); C4 hydrocarbons (about 0.5 mol% to about 0.2 mol%); C5 hydrocarbons (about 0.06 mol%); and C6 hydrocarbons (about 0.02 mol%); and optionally N2 (about 0.1 mol% to about 15 mol%), CO2 (about 0.1 mol% to about 2 mol%), or both N2 (about 0.1 mol% to about 15 mol%) and CO2 (about 0.1 mol% to about 2 mol%).

[0031] In one aspect, the CPO reactant mixture 10 can contain any suitable amount of CO2. In one aspect, the CPO reactant mixture 10 can contain an amount of CO2 effective to provide a syngas 15 having a desired composition (e.g., a syngas having a desired H2 / CO molar ratio; a syngas having a desired M ratio; a syngas having a desired CO2 content; etc.). In some aspects, the CPO reactant mixture 10 can contain CO2 in an amount of about 0.01 mol% to about 5 mol%, or about 0.1 mol% to about 2 mol%, or about 0.2 mol% to about 1 mol%, or about 0.3 mol% to about 0.6 mol%. In other aspects, the CPO reactant mixture 10 can contain CO2 in an amount equal to or greater than about 5 mol%, about 10 mol%, or about 15 mol%.

[0032] In some aspects, CPO reactant mixture 10 can include any suitable amount of hydrocarbons. Hydrocarbons suitable for use in the CPO reactions disclosed herein (e.g., first hydrocarbons) can include C1-C6 hydrocarbons (optionally including some amount of C 7+ %, or about 0.2 wt.% to about 2.5 wt.%, or about 0.25 wt.% to about 1 wt.%, based on the total weight of the hydrocarbon), and CO (e.g., about 0.01 wt.% to about 5 wt.%, or about 0.02 wt.% to about 1 wt.%, or about 0.025 wt.% to about 0.5 wt.%, based on the total weight of the hydrocarbon). For example, a hydrocarbon (e.g., a first hydrocarbon) suitable for use in a CPO reaction disclosed herein may include a C1 hydrocarbon (about 0.01 wt.% to about 10 wt.%, or about 0.05 wt.% to about 5 wt.%, or about 0.1 wt.% to about 1 wt.%, based on the total weight of the hydrocarbon); a C2 hydrocarbon (about 1 wt.%, based on the total weight of the hydrocarbon); 5wt.% to about 75wt.%, or about 20wt.% to about 60wt.%, or about 25wt.% to about 50wt.%); C3 hydrocarbons (about 15wt.% to about 50wt.%, or about 20wt.% to about 40wt.%, or about 25wt.% to about 35wt.%, based on the total weight of the hydrocarbons); C4 hydrocarbons, such as normal-C4 or iso-C4 (about 5wt.% to about 40wt.%, or about 10wt.% to about 30wt.%, or about 15wt.% to about 25wt.%, based on the total weight of the hydrocarbons); C5 hydrocarbons, such as normal-C5 or iso-C5 (about 1wt.% to about 20wt.%, or about 2.5wt.% to about 15wt.%, or about 5wt.% to about 10wt.%, based on the total weight of the hydrocarbons); and C6 hydrocarbons, including C 6+ Hydrocarbons (from about 1 wt.% to about 15 wt.%, or from about 1.5 wt.% to about 10 wt.%, or from about 2.5 wt.% to about 7.5 wt.%, based on the total weight of the hydrocarbons); and optionally N2 (from 0 wt.% to about 10 wt.%, based on the total weight of the hydrocarbons) and / or CO2 (from about 0.01 wt.% to about 5 wt.%, based on the total weight of the hydrocarbons).

[0033] The oxygen used in the CPO reactant mixture 10 may comprise 100% oxygen (essentially pure O2), oxygen (which may be obtained through a membrane separation process), industrial oxygen (which may contain some air), air, oxygen-enriched air, oxygen-containing gaseous compounds (e.g., NO), oxygen-containing mixtures (e.g., O2 / CO2, O2 / H2O, O2 / H2O2 / H2O), oxygen free radical generators (e.g., CH3OH, CH2O), hydroxyl free radical generators, etc., or combinations thereof.

[0034] In one embodiment, the CPO reactant mixture 10 can be characterized by a carbon to oxygen (C / O) molar ratio of less than about 3:1, about 2.6:1, about 2.4:1, about 2.2:1, about 2:1, or about 1.9:1, or equal to or greater than about 2:1, about 2.2:1, about 2.4:1, or about 2.6:1, or about 0.5:1 to about 3:1, or about 0.7:1 to about 2.5:1, or about 0.9:1 to about 2.2:1, or about 1:1 to about 2:1, or about 1.1:1 to about 1.9:1, or about 2:1 to about 3:1, or about 2.2:1 to about 3:1, or about 2.4:1 to about 3:1, or about 2.6:1 to about 3:1, where the C / O molar ratio refers to the total number of moles of carbon (C) in the hydrocarbons in the reactant mixture divided by the total number of moles of O2 in the reactant mixture. For example, when the only carbon source in the CPO reactant mixture 10 is CH4, the CH4 / O2 molar ratio is the same as the C / O molar ratio. As another example, when the CPO reactant mixture 10 contains other carbon sources besides CH4, such as ethane (C2H6), propane (C3H8), butane (C4H 10 ), the C / O molar ratio describes the number of moles of carbon in each compound (e.g., 2 moles of C in 1 mole of C2H6, 3 moles of C in 1 mole of C3H8, 1 mole of C4H 10 4 moles of C in the syngas 15, etc.) As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the C / O mole ratio in the CPO reactant mixture 10 can be adjusted along with other reactor process parameters (e.g., temperature, pressure, flow rate, etc.) to provide a syngas having a desired composition (e.g., a syngas having a desired H2 / CO mole ratio; a syngas having a desired CO2 content; etc.). The C / O mole ratio in the CPO reactant mixture 10 can be adjusted to provide a reduced amount of unconverted hydrocarbons in the syngas 15. The C / O mole ratio in the CPO reactant mixture 10 can be adjusted based on the CPO effluent temperature to reduce (e.g., minimize) the unconverted hydrocarbon content in the produced syngas 15. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, when the syngas is further used in a methanol production process, the unconverted hydrocarbons present in the syngas can undesirably accumulate in the methanol reaction loop, thereby reducing the efficiency of the methanol production process.

[0035] In one embodiment, a portion of the hydrocarbons (e.g., the first hydrocarbon) in the CPO reactant mixture 10 may undergo a thermal decomposition reaction to produce C and H, such as shown in reaction equation (2):

[0036] CH4→C+2H2 (2)

[0037] The increased temperature promotes the decomposition reaction of hydrocarbons (e.g., methane) and increases the H2 content in the CPO reaction zone effluent (e.g., syngas 15). As will be appreciated by those skilled in the art, with the aid of this disclosure, and without wishing to be limited by theory, although the percentage of hydrocarbons in the CPO reactant mixture 10 that undergo decomposition reactions (e.g., the decomposition reaction shown in reaction equation (2)) increases with the increase of the C / O molar ratio in the CPO reactant mixture 10, even at relatively low C / O molar ratios in the CPO reactant mixture 10 (e.g., a C / O molar ratio in the CPO reactant mixture 10 of less than about 2:1), a portion of the hydrocarbons may also undergo decomposition reactions to produce C and H2.

[0038] The CPO reaction is an exothermic reaction (e.g., a heterogeneous catalytic reaction; an exothermic heterogeneous catalytic reaction), which is typically carried out in the presence of a CPO catalyst comprising a catalytically active metal, i.e., a metal active for catalyzing the CPO reaction. The catalytically active metal may comprise a noble metal (e.g., Pt, Rh, Ir, Pd, Ru, Ag, etc., or a combination thereof); a non-noble metal (e.g., Ni, Co, V, Mo, P, Fe, Cu, etc., or a combination thereof); a rare earth element (e.g., La, Ce, Nd, Eu, etc., or a combination thereof); an oxide thereof, etc., or a combination thereof. Typically, a noble metal is a metal that is resistant to corrosion and oxidation in an aqueous environment. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the components of the CPO catalyst (e.g., metals such as noble metals, non-noble metals, rare earth elements) may be phase separated or combined in the same phase.

[0039] In one embodiment, the CPO catalyst suitable for use in the present disclosure may be a supported catalyst and / or an unsupported catalyst. In some embodiments, the supported catalyst may include a carrier, wherein the carrier may be catalytically active (e.g., the carrier may catalyze the CPO reaction). For example, the catalytically active carrier may include a metal gauze or a metal wire mesh (e.g., a Pt gauze or a metal wire mesh); a catalytically active metal monolithic catalyst, etc. In other embodiments, the supported catalyst may include a carrier, wherein the carrier may be catalytically inert (e.g., the carrier cannot catalyze the CPO reaction), such as SiO2; silicon carbide (SiC); alumina; a catalytically inert monolithic carrier, etc. In other embodiments, the supported catalyst may include a catalytically active carrier and a catalytically inert carrier.

[0040] In some embodiments, the CPO catalyst can be wash coated onto a support, wherein the support can be catalytically active or inert, and wherein the support can be a monolith, foam, irregular catalyst particles, etc. In some embodiments, the CPO catalyst can be a monolith, foam, powder, particles, etc. Non-limiting examples of CPO catalyst particle shapes suitable for the present disclosure include cylindrical, disc-shaped, spherical, plate-shaped, elliptical, uniform, irregular, cubic, needle-shaped, etc., or combinations thereof. In some embodiments, the support includes an inorganic oxide, α, β or θ alumina (A12O3), activated A12O3, silica (SiO2), titanium dioxide (TiO2), magnesium oxide (MgO), zirconium oxide (ZrO2), lanthanum (III) oxide (La2O3), yttrium (III) oxide (Y2O3), cerium (IV) oxide (CeO2), zeolite, ZSM-5, perovskite oxide, hydrotalcite oxide, etc., or combinations thereof.

[0041] CPO processes, CPO reactors, CPO catalysts, CPO reaction zones, and CPO catalyst bed configurations suitable for use in the present disclosure are described in more detail in U.S. Provisional Patent Application No. 62 / 522,910, filed on June 21, 2017, entitled “Improved Reactor Designs for Heterogeneous Catalytic Reactions” (International Application No. PCT / IB2018 / 054475, filed on June 18, 2018), and U.S. Provisional Patent Application No. 62 / 521,831, filed on June 19, 2017, entitled “An Improved Process for Syngas Production for Petrochemical Applications” (International Application No. PCT / IB2018 / 054470, filed on June 18, 2018), each of which is incorporated herein by reference in its entirety.

[0042] In one embodiment, a CPO reactor suitable for use in the present disclosure (e.g., including CPO reaction zone 100) may include a tubular reactor, a continuous flow reactor, a fixed bed reactor, a fluidized bed reactor, a moving bed reactor, a riser reactor, a bubbling bed reactor, a circulating bed reactor, an ebullating bed reactor, a rotary kiln reactor, the like, or a combination thereof.

[0043] In some embodiments, the CPO reaction zone 100 may be characterized by at least one CPO operating parameter selected from the following: CPO reaction zone temperature (e.g., CPO catalyst bed temperature); CPO feed temperature (e.g., CPO reactant mixture temperature); target CPO effluent temperature; CPO pressure (e.g., CPO reactor pressure, CPO reaction zone pressure); CPO contact time (e.g., CPO reaction zone contact time); C / O mole ratio in the CPO reactant mixture; steam to carbon (S / C) mole ratio in the CPO reactant mixture, wherein the S / C mole ratio refers to the total number of moles of water (H2O) in the reactant mixture divided by the total number of moles of carbon (C) of hydrocarbons in the reactant mixture; and combinations thereof. For purposes of this disclosure, the CPO effluent temperature is the temperature of the syngas 15 measured at the point where the syngas leaves the CPO reaction zone 100, e.g., the syngas 15 temperature measured at the outlet of the CPO reaction zone 100. For purposes of this disclosure, the CPO effluent temperature (e.g., target CPO effluent temperature) is considered an operating parameter. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the selection of the operating parameters of the CPO reaction zone 100, such as the CPO feed temperature; the CPO pressure; the CPO contact time; the C / O mole ratio in the CPO reactant mixture; the S / C mole ratio in the CPO reactant mixture; the flow rate of the cracking zone feed 60, as further described below, etc., determines the temperature of the effluent syngas 15 as well as the composition of the effluent syngas 15. Furthermore, as will be appreciated by those skilled in the art, and with the aid of the present disclosure, monitoring the CPO effluent temperature can provide feedback for changing other operating parameters (e.g., CPO feed temperature; CPO pressure; CPO contact time; the C / O mole ratio in the CPO reactant mixture; the S / C mole ratio in the CPO reactant mixture; the flow rate of the cracking zone feed 60; etc.) as needed to match the CPO effluent temperature to the target CPO effluent temperature. Furthermore, as will be appreciated by those skilled in the art, and with the aid of the present disclosure, the target CPO effluent temperature is the desired CPO effluent temperature, and the CPO effluent temperature (e.g., measured CPO effluent temperature, actual CPO effluent temperature) may or may not be consistent with the target CPO effluent temperature. In embodiments where the CPO effluent temperature is different from the target CPO effluent temperature, one or more CPO operating parameters (e.g., CPO feed temperature; CPO pressure; CPO contact time; C / O molar ratio in the CPO reactant mixture; S / C molar ratio in the CPO reactant mixture; flow rate of the cracking zone feed 60; etc.) may be adjusted (e.g., modified) to match the CPO effluent temperature to (e.g., be the same as, consistent with) the target CPO effluent temperature.The CPO reaction zone 100 can be operated under any suitable operating parameters that can provide a syngas 15 having a desired composition (e.g., a syngas having a desired H2 / CO molar ratio; a syngas having a desired CO2 content; etc.).

[0044] The CPO reaction zone 100 may be characterized by a CPO feed temperature of about 25° C. to about 600° C., or about 25° C. to about 500° C., or about 25° C. to about 400° C., or about 50° C. to about 400° C., or about 100° C. to about 400° C. In embodiments where the CPO reactant mixture comprises steam, the CPO feed temperature may be as high as about 600° C., or about 575° C., or about 550° C., or about 525° C. In embodiments where the CPO reactant mixture does not comprise steam, the CPO feed temperature may be as high as about 450° C., or about 425° C., or about 400° C., or about 375° C.

[0045] The CPO reaction zone 100 can be characterized by a reaction CPO effluent temperature (e.g., a target CPO effluent temperature, (target) syngas 15 temperature) equal to or greater than about 300°C, about 600°C, about 700°C, about 750°C, about 800°C, or about 850°C, or about 300°C to about 1600°C, about 600°C to about 1400°C, about 600°C to about 1300°C, about 700°C to about 1200°C, about 750°C to about 1150°C, about 800°C to about 1125°C, or about 850°C to about 1100°C.

[0046] In one embodiment, the CPO reaction zone 100 can be characterized by any suitable reactor temperature and / or catalyst bed temperature. For example, the CPO reaction zone 100 can be characterized by a reactor temperature and / or catalyst bed temperature equal to or greater than about 300°C, about 600°C, about 700°C, about 750°C, about 800°C, or about 850°C, or about 300°C to about 1600°C, about 600°C to about 1400°C, about 600°C to about 1300°C, about 700°C to about 1200°C, about 750°C to about 1150°C, about 800°C to about 1125°C, or about 850°C to about 1100°C.

[0047] The CPO reaction zone 100 can be operated at any suitable temperature profile that can provide a syngas 15 having a desired composition (e.g., a syngas having a desired H2 / CO molar ratio; a syngas having a desired CO2 content; etc.). The CPO reaction zone 100 can be operated under adiabatic conditions, non-adiabatic conditions, isothermal conditions, near-isothermal conditions, etc. For the purposes of this disclosure, the term "non-adiabatic conditions" refers to process conditions in which the reaction zone undergoes external heat exchange or transfer (e.g., the reaction zone is heated; or the reaction zone is cooled), which can be direct heat exchange and / or indirect heat exchange. As will be understood by those skilled in the art, and with the help of this disclosure, the terms "direct heat exchange" and "indirect heat exchange" are known to those skilled in the art. In contrast, the term "adiabatic conditions" refers to process conditions in which the reaction zone does not undergo external heat exchange (e.g., the reaction zone is not heated; or the reaction zone is not cooled). Typically, external heat exchange means an external heat exchange system (e.g., a cooling system; a heating system) that requires energy input and / or output. As will be appreciated by those skilled in the art, and with the aid of this disclosure, external heat transfer can also result from heat losses from the catalyst bed (or reactor) due to radiative heat transfer, conductive heat transfer, convective heat transfer, etc., or combinations thereof. For example, the catalyst bed can participate in heat exchange with the external environment and / or with reactor zones upstream and / or downstream of the catalyst bed.

[0048] For the purposes of this disclosure, the term "isothermal conditions" refers to process conditions (e.g., CPO operating parameters) that allow for a substantially constant temperature (e.g., isothermal temperature) of the reaction zone and / or catalyst bed, which can be defined as a temperature that varies less than about ±10°C, about ±9°C, about ±8°C, about ±7°C, or less than about ±6°C, about ±5°C, about ±4°C, about ±3°C, about ±2°C, or about ±1°C, respectively, across the reaction zone and / or catalyst bed. In addition, for the purposes of this disclosure, the term "isothermal conditions" refers to process conditions (e.g., CPO operating parameters) that are effective to provide a syngas 15 having a desired composition (e.g., a desired H2 / CO molar ratio; a desired CO2 content; etc.), wherein the isothermal conditions include a temperature variation of less than about ±10°C in the reaction zone and / or catalyst bed. In embodiments, the CPO reaction zone 100 can be operated under any suitable operating parameters that can provide isothermal conditions.

[0049] For the purposes of this disclosure, the term "near isothermal conditions" refers to process conditions (e.g., CPO operating parameters) that allow for a fairly constant temperature (e.g., a temperature that is close to isothermal) of the reaction zone 100 and / or catalyst bed, which can be defined as a temperature that varies less than about ±100°C, about ±90°C, about ±80°C, about ±70°C, about ±60°C, about ±50°C, about ±40°C, about ±30°C, about ±20°C, about ±10°C, about ±9°C, about ±8°C, about ±7°C, about ±6°C, about ±5°C, about ±4°C, about ±3°C, about ±2°C, or about ±1°C throughout the reactor and / or catalyst bed, respectively. In some embodiments, the near isothermal conditions allow for the temperature of the reactor and / or catalyst bed to vary less than about ±50°C, about ±25°C, or about ±10°C. In addition, for the purposes of this disclosure, the term "near isothermal conditions" is understood to include "isothermal" conditions. Moreover, for the purposes of the disclosure herein, the term "near isothermal conditions" refers to process conditions (e.g., CPO operating parameters) effective to provide a syngas having a desired composition (e.g., a desired H2 / CO molar ratio; a desired CO2 content; etc.), wherein the near isothermal conditions include a temperature variation of the reaction zone and / or catalyst bed of less than about ±100°C. In one embodiment, the method disclosed herein may include conducting a CPO reaction under near isothermal conditions to produce syngas, wherein the near isothermal conditions include a temperature variation of less than about ±100°C throughout the reaction zone 100 and / or the catalyst bed. In an embodiment, the CPO reaction zone 100 may be operated under any suitable operating parameters that can provide near isothermal conditions.

[0050] Near-isothermal conditions can be provided by various process and catalyst variables, such as temperature (e.g., heat exchange or heat transfer), pressure, gas flow rate, reactor configuration, catalyst bed configuration, catalyst bed composition, reactor cross-sectional area, feed gas staging, feed gas injection, feed gas composition, etc. or a combination thereof. Generally, and without wishing to be limited by theory, the term "heat transfer" or "heat exchange" refers to thermal energy exchanged or transferred between two systems (e.g., two reaction zones and / or reactors, such as a CPO reaction zone and / or CPO reactor and a cracking zone and / or cracking reactor), and the terms "heat transfer" or "heat exchange" are used interchangeably for the purposes disclosed herein.

[0051] According to the present disclosure, the target CPO effluent temperature and / or near-isothermal conditions may be achieved by heat exchange or heat transfer. Heat exchange may include heating the reaction zone; and / or cooling the reaction zone. In one embodiment, the target CPO effluent temperature and / or near-isothermal conditions may be achieved by cooling the CPO reaction zone 100. In another embodiment, the target CPO effluent temperature and / or near-isothermal conditions may be achieved by heating the CPO reaction zone 100.

[0052] According to the present disclosure, achieving the target CPO effluent temperature and / or near-isothermal conditions may include indirect heat exchange and / or direct heat exchange. As will be understood by those skilled in the art, and with the aid of the present disclosure, the terms "direct heat exchange" and "indirect heat exchange" are known to those skilled in the art. As used herein, heating a stream (e.g., a cracking zone feed stream), a reaction zone (e.g., a cracking zone), or a reactor (e.g., a cracking reactor) by indirect heat transfer between a stream, a reaction zone, or a reactor and another stream (e.g., CPO product effluent syngas), another reaction zone (e.g., a CPO reaction zone), or another reactor (e.g., a CPO reactor) means heating without direct contact between the contents of the stream, reaction zone, or reactor and the contents of another stream, another reaction zone, or another reactor, while heating a stream (e.g., a cracking zone feed stream), a reaction zone (e.g., a cracking zone), or a reactor (e.g., a cracking reactor) by direct heat transfer between a stream, a reaction zone, or a reactor and another stream (e.g., CPO reaction zone effluent syngas), another reaction zone (e.g., a CPO reaction zone), or another reactor (e.g., a CPO reactor) means heating with direct contact between the contents of the stream, reaction zone, or reactor and the contents of another stream, another reaction zone, or another reactor. In accordance with the present disclosure, target CPO effluent temperatures and / or near-isothermal conditions are achieved at least in part by indirect heat exchange between the CPO reaction zone 100 and the cracking zone 600, as described in further detail below.

[0053] Heat exchange may include external heat exchange, external coolant fluid cooling, reactive cooling, liquid N2 cooling, cryogenic cooling, electrical heating, arc heating, microwave heating, radiant heating, natural gas combustion, solar heating, infrared heating, use of diluents in the CPO reactant mixture, etc. or combinations thereof. For example, reactive cooling may be achieved by conducting an endothermic reaction in a cooling coil / jacket associated with a CPO reactor including the CPO reaction zone 100 (e.g., located in the reactor).

[0054] In some embodiments, the target CPO effluent temperature and / or near-isothermal conditions may be provided by removing process heat from the CPO reaction zone. In other embodiments, the target CPO effluent temperature and / or near-isothermal conditions may be provided by supplying heat to the CPO reaction zone. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the CPO reaction zone may require both heating and cooling to achieve the target CPO effluent temperature and / or near-isothermal conditions.

[0055] In one embodiment, heat exchange or heat transfer can include introducing a coolant, such as a diluent, into the CPO reaction zone 100 to reduce the reactor temperature and / or the catalyst bed temperature while increasing the temperature of the coolant and / or changing the phase of the coolant. The coolant can be reactive or non-reactive. The coolant can be liquid and / or vapor. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the coolant can act as a flame retardant; for example, by reducing the temperature within the reaction zone, by changing the composition of the gas mixture, by reducing the combustion of hydrocarbons to CO2, etc.

[0056] In some embodiments, the CPO reactant mixture 10 may further include a diluent, wherein the diluent helps achieve a target CPO effluent temperature and / or near-isothermal conditions by heat exchange as disclosed herein. The diluent may include water, steam, an inert gas (e.g., argon), N2, CO2, etc., or a combination thereof. Typically, the diluent is inert to the CPO reaction, for example, the diluent does not participate in the CPO reaction. However, as will be appreciated by those skilled in the art, and with the help of the present disclosure, some diluents (e.g., water, steam, CO2, etc.) may undergo chemical reactions other than the CPO reaction in the CPO reaction zone 100, and may change the composition of the resulting synthesis gas 15, which will be described in more detail below; while other diluents (e.g., N2, argon (Ar)) may not participate in the reaction that changes the composition of the resulting synthesis gas. As will be appreciated by those skilled in the art, and with the help of the present disclosure, the diluent may be used to change the composition of the resulting synthesis gas 15. The diluent may be present in the CPO reactant mixture 10 in any suitable amount.

[0057] According to the present disclosure, a target CPO effluent temperature and / or near-isothermal conditions may be achieved at least in part by removing process heat (Q) from the CPO reaction zone 100, e.g., by heating the cracking zone 600 to cool the CPO reaction zone 100. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, a positive Q (direction of arrow 13) pointing "outward" indicates that heat is being transferred from that particular reaction zone, e.g., that particular reaction zone is being cooled. For example, Figure 1 The Q in the represents heat being transferred from the CPO reaction zone 100 (e.g., the CPO reaction zone 100 being cooled) to the cracking process in the cracking zone 600. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, a positive Q pointing "inwardly" (the direction of arrow 13) represents heat being transferred to that particular reaction zone, e.g., that particular reaction zone being heated.

[0058] According to the present disclosure and further detailed below, heat transfer includes cooling the CPO reaction zone 100 while heating the cracking zone 600 (e.g., a cracking reactor including the cracking zone 600). In an embodiment, the cracking zone 600 can produce ethylene by cracking ethane. In an embodiment, a cracking zone feed 60 can be fed to the cracking zone 600, wherein the cracking zone feed comprises a second hydrocarbon, such as an alkane (e.g., ethane, propane, butane, naphtha, etc. or a combination thereof); wherein at least a portion of the second hydrocarbon undergoes an endothermic cracking reaction in the cracking zone 600 to produce a cracking zone product stream 63; and wherein the cracking zone product stream 63 comprises olefins (e.g., ethylene), H2, and unreacted alkanes. Integration of heat transfer between the CPO process and the cracking process is described in more detail in co-pending U.S. provisional patent applications (No. 62 / 787,620, entitled “Catalyst Activity Management in Catalytic Partial Oxidation,” filed on January 2, 2019, and No. 62 / 793,606, entitled “Methanol Production Process from Syngas Produced by Catalytic Partial Oxidation Integrated with Cracking,” filed on January 17, 2019), each of which is incorporated herein by reference in its entirety for purposes not inconsistent with the present disclosure.The heat transfer integration of the CPO process with the cracking process is described in U.S. Provisional Patent Application No. 62 / 820,397, filed on March 19, 2019, entitled “An Integrated Direct Heat Transfer Process for the Production of Methanol and Olefins by Catalytic Partial Oxidation and Cracking,” and the heat transfer integration of the CPO process with the dehydrogenation process is described in U.S. Provisional Patent Application Nos. 62 / 810,631, filed on February 26, 2019, entitled “An Integrated Direct Heat Transfer Process for the Production of Methanol and Olefins by Catalytic Partial Oxidation and Catalytic Selective Dehydrogenation,” and 62 / 810,633, filed on February 26, 2019, entitled “Integrated Indirect Heat Transfer Process for the Production of Syngas and Olefins by Catalytic Partial Oxidation and Catalytic Selective Dehydrogenation,” each of which is incorporated herein by reference in its entirety for purposes not inconsistent with the present disclosure.

[0059] In some embodiments, heat transfer (e.g., heat transfer to achieve a target CPO effluent syngas 15 temperature and / or near-isothermal conditions) excludes heat transfer with the syngas effluent after the effluent syngas 15 leaves the common enclosure 150 that houses the CPO reaction zone 100. In other embodiments, heat transfer (e.g., heat transfer to achieve a target CPO effluent syngas 15 temperature and / or near-isothermal conditions) may include heat transfer with the effluent syngas 15 after the effluent syngas 15 leaves the common enclosure 150.

[0060] CPO reaction zone 100 can be characterized by a CPO pressure (e.g., reaction zone pressure measured at or at the reaction zone outlet) equal to or greater than about 1 bar, about 10 bar, about 20 bar, about 25 bar, about 30 bar, about 35 bar, about 40 bar, or about 50 bar, or less than about 30 bar, or less than about 25 bar, or less than about 20 bar, or less than about 10 bar, or from about 1 bar to about 90 bar, or from about 1 bar to about 70 bar, or from about 1 bar to about 40 bar, or from about 1 bar to about 30 bar, or from about 1 bar to about 25 bar, or from about 1 bar to about 20 bar, or from about 1 bar to about 10 bar, or from about 20 bar to about 90 bar, or from about 25 bar to about 85 bar, or from about 30 bar to about 80 bar.

[0061] The CPO reaction zone 100 may be characterized by a CPO contact time of about 0.001 milliseconds (ms) to about 5 seconds (s), or about 0.001 ms to about 1 s, or about 0.001 ms to about 100 ms, or about 0.001 ms to about 10 ms, or about 0.001 ms to about 5 ms, or about 0.01 ms to about 1.2 ms. Typically, the contact time of a reaction zone comprising a catalyst refers to the average amount of time that a compound (e.g., molecules of the compound) spends in contact with a catalyst (e.g., within a catalyst bed), such as the average amount of time that a compound (e.g., molecules of the compound) spends passing through a catalyst bed. For purposes disclosed herein, contact times of less than about 5 ms may be referred to as a "millisecond regime" (MSR); and a CPO process or CPO reaction characterized by a contact time of less than about 5 ms as disclosed herein may be referred to as a "millisecond regime"-CPO (MSR-CPO) process or reaction, respectively. In some embodiments, CPO reaction zone 100 may be characterized by a contact time of from about 0.001 ms to about 5 ms, or from about 0.01 ms to about 1.2 ms.

[0062] Unless otherwise stated, all CPO operating parameters disclosed herein apply to all embodiments disclosed herein. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, each CPO operating parameter can be adjusted to provide a desired syngas quality, such as a syngas having a desired composition (e.g., a syngas having a desired H2 / CO molar ratio; a syngas having a desired CO2 content; etc.). For example, the CPO operating parameters can be adjusted to provide an increased H2 content of the syngas 15 of the syngas. As another example, the CPO operating parameters can be adjusted to provide a reduced CO2 content of the syngas 15. As yet another example, the CPO operating parameters can be adjusted to provide a reduced unreacted hydrocarbon (e.g., unreacted CH4) content of the syngas 15.

[0063] In one embodiment, the CPO reactant mixture 10 may further comprise a diluent, such as water and / or steam, CO2, N2, argon, etc. The CPO reaction zone 100 may be operated under any suitable operating conditions (e.g., CPO operating parameters) that can provide a CPO reaction zone effluent (e.g., syngas 15) having a desired composition (e.g., a desired H2 / CO molar ratio; a desired CO2 content; etc.); for example, the CPO reaction zone 100 may be operated by introducing water and / or steam and optionally CO2 into the CPO reaction zone 100.

[0064] When carbon (e.g., coke; C produced by the decomposition reaction represented by reaction equation (2)) is present in the reaction zone, water and / or steam diluents can react with the carbon and produce additional CO and H2, for example as shown in reaction equation (3):

[0065]

[0066] As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the presence of water and / or steam in the CPO reaction zone 100 can reduce the amount of coke in the CPO reaction zone 100.

[0067] Further, as will be appreciated by those skilled in the art, and with the aid of this disclosure, water and / or steam may be used to alter the composition of the resulting CPO reaction zone effluent (e.g., syngas 15). Steam may react with methane, for example, as shown in reaction equation (4):

[0068]

[0069] In one embodiment, a diluent comprising water and / or steam can increase the H2 content of the resulting CPO reaction zone effluent (e.g., synthesis gas 15). For example, in embodiments where the CPO reactant mixture 10 comprises a water and / or steam diluent, the resulting CPO reaction zone effluent (e.g., synthesis gas 15) can be characterized by a molar ratio of H2 to CO that is increased compared to the molar ratio of H2 to CO of a CPO reaction zone effluent (e.g., synthesis gas 15) produced by an otherwise similar process using a reactant mixture comprising hydrocarbons and O2 without the water and / or steam diluent. Without wishing to be limited by theory, the reforming reaction (e.g., as shown in reaction equation (4)) is an endothermic reaction. The reforming reaction as shown in reaction equation (4) can remove a portion of the process heat (e.g., heat generated by the exothermic CPO reaction (e.g., as shown in reaction equation (1))).

[0070] In the presence of water and / or steam in the CPO reaction zone 100, CO may react with water and / or steam to form CO2 and H2 via a water gas shift (WGS) reaction, for example as shown in reaction equation (5):

[0071]

[0072] Although the WGS reaction can increase the H2 / CO molar ratio of the syngas produced by the CPO reaction zone 100, it also produces CO2.

[0073] In one embodiment, the CPO reaction zone 100 can be operated with an S / C molar ratio in the CPO reactant mixture 10 of less than about 2.4: 1, about 2: 1, about 1.5: 1, about 1: 1, about 0.8: 1, or about 0.5: 1, or from about 0.01: 1 to less than about 2.4: 1, or from about 0.05: 1 to about 2: 1, from about 0.1: 1 to about 1.5: 1, from about 0.15: 1 to about 1: 1, from about 0.2: 1 to about 0.8: 1. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the amount of steam introduced into the CPO reaction zone for use as a diluent in the CPO reactions disclosed herein is significantly less than the amount of steam used in steam reforming (e.g., SMR) processes, and thus, the methods for producing syngas disclosed herein can produce syngas having a lower amount of H2 than the amount of H2 in the syngas produced by steam reforming.

[0074] The S / C molar ratio in the CPO reactant mixture 10 can be adjusted based on a desired CPO effluent temperature (e.g., a target CPO effluent temperature) to increase (e.g., maximize) the H2 content of the CPO reaction zone effluent (e.g., syngas 15). As will be appreciated by those skilled in the art, and with the aid of the present disclosure, reaction (4) that consumes steam in the CPO reaction zone 100 is preferred over the water gas shift (WGS) reaction (5) in the CPO reaction zone 100 because reaction (4) allows for an increase in the H2 content of the CPO reaction zone effluent (e.g., syngas 15) and the M ratio of the CPO reaction zone effluent (e.g., syngas 15), where the M ratio is a molar ratio defined as (H2-CO2) / (CO+CO2). Furthermore, as will be appreciated by those skilled in the art, and with the aid of the present disclosure, reaction (4) converts water and CO into both H2 and CO2.

[0075] In one embodiment, the amount of methane reacted according to reaction (3) in CPO reaction zone 100 is less than the amount of methane reacted according to reaction (1) in CPO reaction zone 100. In one embodiment, less than about 50 mol%, or less than about 40 mol%, or less than about 30 mol%, or less than about 20 mol%, or less than about 10 mol% of the hydrocarbons (e.g., methane) in CPO reaction zone 100 react with steam.

[0076] Without wishing to be bound by theory, the presence of water and / or steam in CPO reaction zone 100 changes the flammability of CPO reactant mixture 10, thereby providing a wider range of practical C / O mole ratios in CPO reactant mixture 10. Additionally, without wishing to be bound by theory, the presence of water and / or steam in CPO reaction zone 100 allows for the use of lower C / O mole ratios in CPO reactant mixture 10. Furthermore, without wishing to be bound by theory, the presence of water and / or steam in CPO reaction zone 100 allows for the operation of CPO reaction zone 100 at relatively high pressures.

[0077] As will be appreciated by those skilled in the art, and with the aid of this disclosure, the introduction of water and / or steam into the CPO reaction zone 100 may result in an increase in the amount of unreacted hydrocarbons in the CPO reaction zone effluent, e.g., the syngas 15. Additionally, as will be appreciated by those skilled in the art, and with the aid of this disclosure, methanol (MeOH or CH3OH) production processes are generally tolerant of limited amounts of unreacted hydrocarbons in the syngas.

[0078] In some embodiments, the CPO reaction zone effluent (e.g., synthesis gas 15) may contain less than about 7.5 mol%, or less than about 5 mol%, or less than about 2.5 mol% hydrocarbons (e.g., unreacted hydrocarbons, unreacted CH4). In such embodiments, the CPO reaction zone effluent (e.g., synthesis gas 15) may be produced in a CPO process using water and / or steam. In such embodiments, the CPO reaction zone effluent (e.g., synthesis gas 15) may be used for methanol synthesis.

[0079] In addition, because O2 is present in the CPO reactant mixture 10, carbon (e.g., coke; C produced by the decomposition reaction shown in reaction equation (2)) present in the reaction zone can also react with O2, for example, as shown in reaction equation (6):

[0080] C+O2→CO2 (6)

[0081] When carbon (e.g., coke; C produced by the decomposition reaction represented by reaction equation (2)) is present in the reaction zone, CO (e.g., introduced into CPO reaction zone 100 as part of CPO reactant mixture 10 and / or produced by the reaction represented by reaction equation (6)) can react with the carbon, for example, as shown in reaction equation (7):

[0082]

[0083] The amount of CO2 in the resulting CPO reaction zone effluent (e.g., syngas 15) is thereby reduced. As will be appreciated by those skilled in the art, and with the aid of this disclosure, the presence of CO2 in the CPO reaction zone 100 can reduce the amount of coke in the CPO reaction zone 100.

[0084] Moreover, in a dry reforming reaction, CO2 can react with methane, for example as shown in reaction equation (8):

[0085]

[0086] Thereby reducing the amount of CO2 in the resulting CPO reaction zone effluent (e.g., synthesis gas 15). Without wishing to be bound by theory, the dry reforming reaction (e.g., as shown in reaction equation (8)) is an endothermic reaction (e.g., a highly endothermic reaction). The dry reforming reaction can remove a portion of the process heat (e.g., heat generated by the exothermic CPO reaction (e.g., as shown in reaction equation (1))).

[0087] In one embodiment, a diluent comprising CO2 can increase the CO content of the resulting CPO reaction zone effluent (e.g., synthesis gas 15). For example, in an embodiment where the CPO reactant mixture 10 comprises a CO2 diluent, the CPO reaction zone effluent (e.g., synthesis gas 15) can be characterized by a molar ratio of H2 to CO that is reduced compared to the molar ratio of H2 to CO of a CPO reaction zone effluent (e.g., synthesis gas) produced by an otherwise similar process using a reactant mixture comprising hydrocarbons and O2 without the CO2 diluent. Without wishing to be limited by theory, CO2 can react with coke within the CPO reaction zone 100 and produce additional CO, for example, as shown in reaction equation (7). In addition, without wishing to be limited by theory, CO2 can participate in a dry reforming reaction of methane, thereby producing additional CO and H2, for example, as shown in reaction equation (8). Dry reforming of methane is typically accompanied by a reaction between CO2 and H2, which results in the formation of additional CO and water.

[0088] The use of CO2 in the CPO reactant mixture 10 can advantageously reduce the amount of hydrocarbons that are converted to CO2, for example, by combustion reactions, in the CPO reaction zone 100. Without wishing to be bound by theory, and in accordance with Le Chatelier's principle, as the amount of CO2 in the reactant mixture increases, the equilibrium of the hydrocarbon dry reforming reaction will shift toward consuming CO2, thereby allowing a higher amount of hydrocarbons to be converted to synthesis gas.

[0089] As will be appreciated by those skilled in the art, with the aid of this disclosure, and without wishing to be bound by theory, increasing the amount of CO2 in the CPO reactant mixture 10 can result in an increase in the amount of CO in the syngas 15, thereby resulting in a decrease in the H2 / CO molar ratio and / or a decrease in the M ratio of the syngas 15. In some aspects, the CPO reactant mixture 10 can include an amount of CO2 effective to provide a syngas 15 having a desired composition (e.g., a syngas having a desired H2 / CO molar ratio; a syngas having a desired M ratio; a syngas having a desired CO2 content; etc.). In aspects where the H2 / CO molar ratio and / or the M ratio of the syngas 15 are below or substantially below the desired H2 / CO molar ratio and / or the desired M ratio, respectively, the syngas 15 can be contacted with an increased amount of H2 (e.g., the H2 stream 73), for example, an amount of H2 (e.g., the H2 stream 73) effective to provide a hydrogen-enriched syngas 16 having a desired composition (e.g., a syngas having a desired H2 / CO molar ratio; a syngas having a desired M ratio; a syngas having a desired CO2 content; etc.). In aspects where the H2 / CO mole ratio and / or M ratio of the syngas 15 is less than or slightly less than a desired H2 / CO mole ratio and / or desired M ratio, respectively, the syngas 15 can be contacted with a reduced amount of H2 (e.g., H2 stream 73), e.g., an amount of H2 (e.g., H2 stream 73) effective to provide a hydrogen-enriched syngas 16 having a desired composition (e.g., syngas having a desired H2 / CO mole ratio; syngas having a desired M ratio; syngas having a desired CO2 content; etc.). As will be appreciated by those skilled in the art, and with the aid of the present disclosure, when the syngas 15 has a relatively high H2 / CO mole ratio and / or M ratio, it may not be necessary to use the entire amount of available H2 (e.g., H2 stream 73), and it may be sufficient to use only a portion of the available H2 (e.g., H2 stream 73).

[0090] In aspects where the CPO reactant mixture 10 comprises both steam and CO2, the CPO reaction zone 100 can be operated with a steam to CO2 (S / CO2) molar ratio in the CPO reactant mixture 10 of less than about 100,000:1, about 50,000:1, about 10,000:1, about 5,000:1, about 1,000:1, or about 500:1, or from about 0.1:1 to about 100,000:1, from about 0.2:1 to about 50,000:1, from about 1:1 to about 10,000:1, from about 5:1 to about 5,000:1, from about 10:1 to about 1,000:1, or from about 25:1 to about 500:1.

[0091] As will be understood by those skilled in the art, and with the aid of the present disclosure, a CO2-lean syngas has a higher M ratio than a CO2-rich syngas: the lower the CO2 content of the syngas, the higher the M ratio of the syngas. The CO2 content of the syngas can be adjusted as described in more detail in co-pending U.S. Provisional Patent Application 62 / 787,574, entitled “Hydrogen Enrichment in Syngas Produced via Catalytic Partial Oxidation,” filed on January 2, 2019; which is incorporated herein by reference in its entirety for purposes not inconsistent with the present disclosure.

[0092] In one embodiment, a CPO reaction zone effluent (e.g., synthesis gas 15) may be recovered from a CPO reaction zone 100, wherein the CPO reaction zone effluent (e.g., synthesis gas 15) comprises H2, CO, water, CO2, and unreacted hydrocarbons (e.g., unreacted first hydrocarbons, unreacted methane, and optionally unreacted second hydrocarbons). The CPO reaction zone effluent synthesis gas 15 disclosed herein may be characterized by an H2 / CO molar ratio greater than about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, or about 2.0. In some embodiments, the CPO reaction zone effluent synthesis gas 15 disclosed herein may be characterized by an H2 / CO molar ratio of about 1.3 to about 2.3, about 1.4 to about 2.3, about 1.5 to about 2.3, about 1.6 to about 2.3, about 1.7 to about 2.2, or about 1.8 to about 2.1. In one embodiment, the CPO reaction zone effluent syngas 15 can be characterized by an M ratio equal to or greater than about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, or about 1.8, about 1.3 to about 2.3, or about 1.4 to about 2.3, or about 1.5 to about 2.3, or about 1.6 to about 2.3, or about 1.7 to about 2.2, or about 1.8 to about 2.2.

[0093] In some embodiments, the CPO reaction zone syngas 15 may be used in downstream processes (eg, methanol production) without further processing to enrich the H 2 content of the CPO reaction zone effluent syngas 15 .

[0094] In other embodiments, the CPO reaction zone effluent syngas 15 may be further treated prior to use in a downstream process (e.g., methanol production) CPO reaction zone effluent syngas 15. The CPO reaction zone effluent syngas 15 may be treated to enrich its H2 content; for example, by contacting the CPO reaction zone effluent syngas 15 with additional (e.g., supplemental) H2 (e.g., H2 stream 73, further described below).

[0095] As will be appreciated by those skilled in the art, and with the aid of the present disclosure, although the CPO reaction zone effluent syngas 15 may be characterized by an H2 / CO molar ratio greater than about 1.8, which may be suitable for methanol synthesis, the CPO reaction zone effluent syngas 15 may be treated to further increase its H2 content. Furthermore, as will be appreciated by those skilled in the art, and with the aid of the present disclosure, the CPO reaction zone effluent syngas 15 may be minimally treated, such as to recover unreacted hydrocarbons, diluents, water, etc., without substantially altering the H2 / CO molar ratio of the CPO reaction zone effluent syngas 15. For example, water may be condensed and separated from the CPO reaction zone effluent syngas 15, such as in a condenser.

[0096] In one embodiment, the process disclosed herein may further include: (i) recovering at least a portion of the unreacted hydrocarbons (e.g., unreacted first hydrocarbons, optionally unreacted methane, optionally unreacted second hydrocarbons) from the CPO reaction zone effluent syngas 15 to produce recovered hydrocarbons, and (ii) recycling at least a portion of the recovered hydrocarbons to the CPO reaction zone 100. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, despite the relatively high conversion rates that can be achieved in the CPO process (e.g., equal to or greater than about 90% conversion), the unconverted hydrocarbons may be recovered and recycled back to the CPO reaction zone 100. In some embodiments, at least a portion of the recovered hydrocarbons may be used as a fuel (e.g., to preheat the CPO reactant mixture; to heat the cracking zone 600) and / or fed to the cracking zone 600.

[0097] In one embodiment, the CO2 content of the CPO reaction zone effluent syngas 15 can be less than about 7 mol%, about 6 mol%, about 5 mol%, about 4 mol%, about 3 mol%, about 2 mol%, or about 1 mol%, or about 0.1 mol% to about 7 mol%, about 0.25 mol% to about 5 mol%, or about 0.5 mol% to about 3 mol%. For example, the side reactions represented by reaction equations (7) and / or (8) can result in a CPO reaction zone effluent syngas 15 having a CO2 content of about 0.1 mol% to about 7 mol%.

[0098] In one embodiment, the hydrocarbon content of the CPO reaction zone effluent synthesis gas 15 can be less than about 10 mol%, about 7.5 mol%, about 5 mol%, about 4 mol%, about 3 mol%, about 2 mol%, about 1 mol%, about 0.1 mol% or about 0.01 mol%.

[0099] Back to Figure 1In some embodiments, the method disclosed herein includes the step of feeding a cracking zone feed 60 to a cracking zone 600 to produce a cracking zone product stream 63. In some embodiments, the cracking zone product stream 63 may include olefins, such as ethylene, propylene, butene, etc. or combinations thereof, as well as H2 and other hydrocarbons. The cracking zone product stream 63 may further include other unsaturated hydrocarbons, such as butadiene, C 5-6 Olefins, C 6-8 Aromatic hydrocarbons, etc. For example, in addition to H2, the cracking zone product stream 63 may contain olefins and other unsaturated hydrocarbons. The cracking zone 600 may include any suitable cracking zone configured to convert saturated hydrocarbons (e.g., alkanes) into olefins. For example, the cracking zone 600 may include any suitable cracking zone configured to convert a cracking zone feed 60 containing a second hydrocarbon (e.g., saturated hydrocarbons, alkanes) into a cracking zone product stream 63 containing olefins. Non-limiting examples of cracking zones (e.g., cracking reactors) suitable for use in the present disclosure include thermal cracking zones (e.g., thermal cracking reactors), catalytic cracking zones (e.g., catalytic cracking reactors), steam cracking zones (e.g., steam cracking reactors), etc., or combinations thereof. As will be understood by those skilled in the art, and with the help of the present disclosure, thermal cracking processes, catalytic thermal processes, steam cracking processes, etc., or combinations thereof are known to those skilled in the art.

[0100] Without wishing to be bound by theory, cracking refers to an endothermic reaction that converts alkanes into olefins and hydrogen. Generally, as will be appreciated by those skilled in the art, and with the aid of the present disclosure, heat (e.g., thermal energy) must be supplied to the cracking zone to enable the cracking reaction that produces olefins to proceed. According to the present disclosure, at least a portion of the heat Q used by the cracking zone as disclosed herein is supplied by the CPO reaction zone 100. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the process heat from the CPO reaction zone 100 may not be sufficient to supply all the heat required by the cracking zone 600. In one aspect, a fuel stream may be combusted to supply the additional heat required by the cracking zone 600.

[0101] In some embodiments, the cracking zone may include a gas cracking zone (e.g., within a gas cracking reactor). For example, in embodiments where the cracking zone feed 60 comprises ethane and / or propane, the cracking zone 600 may include a gas cracking zone. In other embodiments, the cracking zone may include a liquid cracking zone (e.g., within a liquid cracking reactor). For example, in embodiments where the cracking zone feed 60 comprises C 4+ In embodiments where the hydrocarbons, such as butane, naphtha fractions (eg, naphtha feedstock), etc., or combinations thereof; cracking zone 600 may include a liquid cracking zone.

[0102] In one embodiment, the second hydrocarbon suitable for feeding to the cracking zone 600 disclosed herein may include saturated hydrocarbons, such as alkanes. Non-limiting examples of the second hydrocarbon suitable for feeding to the cracking zone disclosed herein may include alkanes, ethane, propane, butane, naphtha, etc. or combinations thereof. In some embodiments, the first hydrocarbon and the second hydrocarbon may be the same. For example, a naphtha feed may be introduced into the cracking zone 600 and the CPO reaction zone 100. In other embodiments, the first hydrocarbon and the second hydrocarbon may be different. As another example, ethane (e.g., the second hydrocarbon) may be introduced into the cracking zone 600, and methane (e.g., the first hydrocarbon) may be introduced into the CPO reaction zone 100.

[0103] If we now refer to Figures 2A-2C As described in the embodiments of the present invention, in embodiments, the common housing 150 includes both the CPO reaction zone 100 (such that the CPO catalyst is disposed within the common housing 150) and the cracking zone 600. In embodiments, the common housing 150 further includes a cracking reactor disposed therein, wherein the cracking reactor is characterized by a cracking reactor outer surface and a cracking reactor inner surface, and wherein the cracking reactor inner surface defines the cracking zone 600. In embodiments, the cracking reactor includes one or more tubes (or "coils") 601 disposed within the common housing 150, and heating the cracking zone 600 includes heating the second hydrocarbon within the one or more tubes 601 disposed within the common housing 150. Figure 2A As shown in the embodiment of the present invention, in the embodiment, the CPO catalyst of the CPO reaction zone 100 is located above one or more tubes 601. Figure 2B As shown in the embodiment of the present invention, in the embodiment, the CPO catalyst of the CPO reaction zone 100 is located below one or more tubes 601. Figure 2C As shown in the embodiment of the present invention, in the embodiment, the CPO catalyst of the CPO reaction zone 100 is located around one or more tubes 601 and / or on one or more tubes 601. Therefore, in the embodiment, the CPO catalyst is disposed in a common housing, and the CPO catalyst is located above one or more tubes 601, below one or more tubes 601, around one or more tubes 601, on one or more tubes 601, or a combination thereof.

[0104] In embodiments, the common housing 150 further comprises a furnace zone, wherein a fuel stream may be combusted in the furnace zone to provide additional heat for the endothermic cracking reaction. In embodiments, heating the cracking zone 600 comprises heating a cracking zone feed 60 within a cracking reactor disposed within the common housing 150. In embodiments, the outer surface of the cracking reactor does not contact the CPO catalyst (e.g., Figure 2AIn an embodiment, the CPO reaction zone 100 and the cracking zone 600 are adjacent to each other, and the CPO reaction zone 100 and the cracking zone 600 do not overlap in space (e.g. Figure 2A In an embodiment, at least a portion of the outer surface of the cracking reactor contacts the CPO catalyst (e.g. Figure 2B-2C In an embodiment, the common housing 150 includes a CPO catalyst bed disposed therein, wherein the CPO catalyst bed includes a CPO catalyst, and at least a portion of the cracking reactor is disposed within the CPO catalyst bed (e.g. Figure 2B In an embodiment, the CPO catalyst layer coats at least a portion of the outer surface of the cracking reactor (e.g. Figure 2C In embodiments, the CPO catalyst layer has a thickness of less than or equal to about 500, 400, 300, 200, or 100 micrometers (μm).

[0105] A flow control valve may be used to introduce the CPO reactant mixture 10 into the CPO reaction zone 100, and / or a flow control valve may be used to introduce the cracking zone feed 60 into the cracking zone 600. The flow of the cracking zone feed 60 may be regulated by the set temperature of the CPO reaction zone 100. If the temperature of the CPO reaction zone 100 rises above the set temperature, the flow of the cracking zone feed 60 may be increased by the flow control valve on the cracking zone feed 60 to enhance heat removal from the CPO reaction zone 100 (e.g., the CPO catalyst bed of the CPO reaction zone 100), thereby returning the temperature of the CPO reaction zone 100 to the set CPO temperature. If the temperature of the CPO reaction zone 100 is below the set temperature of the CPO reaction zone 100, the flow control valve on the cracking zone feed 60 may be closed to reduce or eliminate the flow of the cracking zone feed 60 to the cracking zone 600. In this way, potential runaway of the CPO reaction zone 100 can be prevented, and in an embodiment, near-isothermal conditions within the CPO reaction zone 100 can be maintained. In an embodiment, multiple cracking reactor tubes are used so that one set of cracking tubes (e.g., one cracking zone) can be online in cracking mode while another set is in decoking mode. The size of the tube 601 can be determined based on the oxidation throughput of the CPO reaction zone 100 (e.g., the flow rate of the CPO reactant mixture 10). In an embodiment, the cracking zone 600 is characterized by a cracking zone temperature in the range of about 400°C to about 1200°C, about 600°C to about 1100°C, about 600°C to about 850°C, or less than or equal to about 1200, 1100, 1000, 900, 800, 700, 600, 500, or 400°C.

[0106] The cracking zone product stream 63 may be further subjected to further purification or separation processes, for example, for recovery of one or more components. In an embodiment, a separation unit may be used to separate an H2 stream 73, an unreacted hydrocarbon (e.g., an unreacted second hydrocarbon) stream 82, and an olefin stream 81 from the cracking zone product stream 63. In an embodiment, the separation unit may include a gas-liquid separation unit, a pressure swing adsorption (PSA) unit, a membrane separation unit, a cryogenic separation unit, an oil scrubber separation unit, a size exclusion unit, or a combination thereof. Figure 1 In the embodiment described, the separation unit may include a second H2 recovery unit 700 and / or a separator 800. In the embodiment, the method therefore further includes separating at least a portion of the cracking zone product stream 63 into an H2 stream 73 and a hydrocarbon stream (HC stream) 74, wherein the HC stream 74 contains olefins and unreacted hydrocarbons. The second H2 recovery unit 700 is configured to separate the H2 stream 73 from the HC stream 74. The HC stream 74 contains a higher concentration of olefins (e.g., ethylene, as well as propylene, butene, etc.), methane, and unreacted second hydrocarbons (e.g., alkanes, ethane, propane, butane, naphtha, etc., or a combination thereof) than the cracking zone product stream 63, while the H2 stream 73 contains a higher concentration of H2 than the cracking zone product stream 63. In some embodiments, the second H2 recovery unit 700 may include any suitable separation unit configured to separate the cracking zone product stream 63 into an H2 stream 73 and an HC stream 74. For example, the separation unit of the second H2 recovery unit 700 can adopt gas-liquid separation, distillation, cryogenic distillation, extractive distillation, selective adsorption, selective absorption, etc. or a combination thereof. In an embodiment, the second H2 recovery unit 700 can include a gas-liquid separator, a distillation tower, a cryogenic distillation tower, a plate and / or packed separation tower, a compressor, a heat exchanger, a cooling tower, a PSA unit, etc. In an embodiment, the second H2 recovery unit 700 includes a PSA. In an embodiment, the PSA of the second H2 recovery unit 700 and the first H2 recovery unit 500 (further described below) is the same PSA.

[0107] In one embodiment, for example, Figure 1 As shown, at least a portion 63a of the cracking zone product stream 63 can be introduced into a second H2 recovery unit 700 (e.g., a gas-liquid separation unit, a PSA unit, a membrane separation unit, a low-temperature separation unit, etc. or a combination thereof) to further enrich the H2 content of the cracking zone product stream 63; for example, to recover H2 from the cracking zone product stream 63.

[0108] In one embodiment, for example, Figure 1As shown, at least a portion 63b of the cracking zone product stream 63 may be introduced into a first H2 recovery unit 500 (e.g., a PSA unit, a membrane separation unit, a cryogenic separation unit, the like, or a combination thereof) to further enrich the H2 content of the cracking zone product stream 63; e.g., to recover H2 from the cracking zone product stream 63. In such an embodiment, the cracking zone product stream 63 may be compressed prior to introduction into the first H2 recovery unit 500. As will be appreciated by those skilled in the art, and with the aid of this disclosure, the methanol production loop operates at a fairly high pressure (e.g., about 70 bar to 100 bar), and thus such a stream introduced into the methanol reaction loop (e.g., at least a portion 63b of the cracking zone product stream 63) must be compressed to meet the pressure requirements of the methanol production loop.

[0109] In some embodiments, the first H2 recovery unit 500 and the second H2 recovery unit 700 can be the same H2 recovery unit or include the same H2 recovery unit (e.g., the same PSA). In other embodiments, the first H2 recovery unit 500 and the second H2 recovery unit 700 can be different H2 recovery units or include different H2 recovery units (e.g., different PSAs).

[0110] In some embodiments, at least a portion 63a of the cracking zone product stream 63 can be separated into an H2 stream 73 and an HC stream 74 in the second H2 recovery unit 700. The H2 stream 73 comprises at least a portion of the H2 of the cracking zone product stream 63, and optional hydrocarbons (e.g., hydrocarbons present in the cracking zone product stream 63, such as olefins (e.g., ethylene), unreacted second hydrocarbons (e.g., ethane, propane, butane, naphtha)). The HC stream 74 comprises at least a portion of the hydrocarbons of the cracking zone product stream 63 (e.g., olefins (e.g., ethylene), unreacted second hydrocarbons (e.g., ethane, propane, butane, naphtha)), and optional H2. In one aspect, the H2 concentration in the H2 stream 73 is greater than the H2 concentration in the cracking zone product stream 63. In one aspect, the hydrocarbon concentration in the HC stream 74 is greater than the hydrocarbon concentration in the cracking zone product stream 63.

[0111] In an embodiment, the second H2 recovery unit 700 includes an oil scrubber separation unit and a size exclusion unit. Such a second H2 recovery unit 700 may further include a cooler, a gas-liquid separator, an oil regenerator and / or a cryogenic condenser. For example, in Figure 3In an embodiment of the present invention, the second H2 recovery unit 700' includes a cooler C1, a gas-liquid separator 710, an oil scrubber separation unit 720, an oil regenerator 730, a cryogenic condenser 740, and a size exclusion unit 750. In such an embodiment, the cracking zone product stream 63 or at least a portion 63a thereof (e.g., including cracked products (e.g., olefins), unreacted hydrocarbons (e.g., unreacted second hydrocarbons), H2, etc.) can be washed in the oil scrubber separation unit 720. The cracking zone product stream or a portion thereof (63 / 63a) can be cooled in the cooler C1 (e.g., cooled to a temperature of less than or equal to about 100°C, or less than or equal to about 80°C, or less than or equal to about 60°C, or about 20°C to about 100°C, or about 30°C to about 80°C, or about 40°C to about 60°C) to provide a cooled cracking zone product stream 701. The cooled cracking zone product stream 701 may be introduced into a vapor-liquid separator 710 , wherein a liquid stream 711 may be separated from the cooled cracking zone product stream 701 to provide a dehydrated cracking zone product stream 712 .

[0112] The gas-liquid separator 710 of the second H2 recovery unit 700 / 700' may include any suitable gas-liquid separator configured to separate the cooled cracking zone product stream 701 into a liquid stream 711 comprising water and a dehydrated cracking zone product stream 712 having a reduced water content relative to the cooled cracking zone product stream 701. For example, the gas-liquid separator 710 may include a vapor-liquid separator, a flash drum, a knockout drum, a knockout drum, a compressor suction drum, etc. The liquid stream 711 may be recovered from the gas-liquid separator 710 as a bottom stream. The liquid stream 711 recovered from the gas-liquid separator 710 may include water, C 5+ Hydrocarbons such as pentane, pentene, hexane, hexene, benzene, toluene, xylene, etc. or combinations thereof. As will be appreciated by those skilled in the art, and with the aid of this disclosure, the liquid stream 711 recovered from the gas-liquid separator 710 may further contain trace amounts of C 4- Hydrocarbons, such as butane, butene, butadiene, etc. In addition to cracking zone product hydrocarbons (e.g., C2, C3 and C4 hydrocarbons, and some optional trace C5 hydrocarbons) including olefins, methane, ethane, propane, unreacted second hydrocarbons, H2, CO and / or CO2, the dehydrated cracking zone product stream 712 may contain less than about 5 mol%, about 4 mol%, about 3 mol%, about 2 mol%, about 1 mol%, about 0.5 mol%, about 0.1 mol%, about 0.05 mol% or about 0.01 mol% of water. In embodiments (e.g., wherein the cracking zone product stream 63 / 63a does not contain a large amount of water), the second H2 recovery unit 700 / 700' may not have a cooler C1 and / or a gas-liquid separator 710.

[0113] In some aspects, the liquid stream 711 can be further introduced into a liquid-liquid separator, wherein the liquid-liquid separator can include any suitable liquid-liquid separator configured to separate the liquid stream 711 into an aqueous phase stream containing water and an oil phase stream containing hydrocarbons. For example, the liquid-liquid separator can include a horizontal gravity settling tank, a vertical gravity settling tank, a coalescer, a membrane separator, etc. or a combination thereof. In some aspects, the aqueous phase stream can include water and trace amounts of C 4- Hydrocarbons, such as butane, butene, butadiene, etc. or combinations thereof. The oil phase stream may contain C 5+ Hydrocarbons such as pentane, pentene, hexane, hexene, benzene, toluene, xylene, etc. or combinations thereof; and trace amounts of water and / or C 4- Hydrocarbons such as butane, butene, butadiene, etc.

[0114] In some aspects, the gas-liquid separator 710 may include a gas-liquid-liquid separator. The gas-liquid-liquid separator may include any suitable gas-liquid-liquid separator configured to separate the cooled cracking zone product stream 701 into a dehydrated cracking zone product stream 712, an aqueous phase stream comprising water, and an oil phase stream comprising hydrocarbons. For example, the gas-liquid-liquid separator may include a gas-liquid separator (e.g., a vapor-liquid separator, a flash tank, a knockout drum, a knockout tank, a compressor suction tank, etc.) integrated with a liquid-liquid separator (e.g., a horizontal gravity settling tank, a vertical gravity settling tank, a coalescer, a membrane separator, etc., or a combination thereof). In addition to cracking zone product hydrocarbons including olefins, methane, ethane, propane, unreacted second hydrocarbons, H2, CO, and / or CO2, the dehydrated cracking zone product stream 712 recovered from the gas-liquid-liquid separator may contain less than about 5 mol%, about 4 mol%, about 3 mol%, about 2 mol%, about 1 mol%, about 0.5 mol%, about 0.1 mol%, about 0.05 mol%, or about 0.01 mol% water. The aqueous phase stream recovered from the gas-liquid-liquid separator may contain water and trace amounts of C 4- Hydrocarbons such as butane, butene, butadiene, etc. or combinations thereof. The oil phase stream recovered from the gas-liquid-liquid separator may contain C 5+ Hydrocarbons such as pentane, pentene, hexane, hexene, benzene, toluene, xylene, etc. or combinations thereof; and trace amounts of water and / or C 4- Hydrocarbons such as butane, butene, butadiene, etc.

[0115] In the oil scrubber separation unit 720, the cracking zone product stream 63 / 63a or the dehydrated cracking zone product stream 712 is contacted with the wash oil in the oil stream 733 to provide a hydrogen-containing stream 722 and a wash oil stream 721 comprising waste oil (e.g., wash oil and C washed from the introduced cracking zone product stream 63 / 63a or the dehydrated cracking zone product stream 712). 2+Hydrocarbons). The hydrogen-containing stream 722 may contain trace amounts of C 2+ Hydrocarbons, as well as H2, CH4, CO and CO2.

[0116] The oil regenerator 730 can be used to separate the regenerated oil stream 731 from the hydrocarbon stream 74, which contains cracked products (including olefins and unreacted hydrocarbons (e.g., unreacted second hydrocarbons). The regenerated oil stream 731 can be reintroduced into the oil scrubber separation unit 720, for example, through the oil stream 733.

[0117] The remaining hydrocarbons may be removed from the hydrogen-containing stream 722 to provide the H2 stream 73. For example, in an embodiment, the hydrogen-containing stream 722 may be cryogenically condensed (e.g., less than or equal to about 10°C, or less than or equal to about 5°C, or less than or equal to about 0°C, or about -40°C to about 10°C, or about -32°C to about 5°C, or about -20°C to about 0°C) in a cryogenic condenser 740 to remove the C 2+ Stream 742 and C 2+ The reduced hydrogen-containing stream 741 is separated. 2+ The reduced hydrogen-containing stream 741 can be size excluded in a size exclusion unit 750 to provide a H2 stream 73 and another C 2+ Stream 752. Cryogenic condenser 740 and size exclusion unit 750 may include methods known to those skilled in the art and operable with the aid of this disclosure to provide C 2+ Any cryogenic condenser and size exclusion unit for the separation of streams 742 and 752. For example, size exclusion unit 750 may include any suitable number of size exclusion units, such as 1, 2, 3, 4, 5 or more size exclusion units. In an embodiment, C 2+ Streams 742 and / or 752 may be combined with HC stream 74 , for example, prior to subsequent processing and / or use of HC stream 74 .

[0118] In one embodiment, the HC stream 74 can be further subjected to one or more separation steps to recycle olefins. For example, ethylene can be recovered from the HC stream 74, wherein ethylene can be further used in, for example, a polymerization process. In one embodiment, at least a portion 74a of the HC stream 74 is introduced into a separator 800, which is configured to separate at least a portion 74a of the HC stream 74 into an olefin stream 81 and an unreacted hydrocarbon stream 82, wherein the olefin stream 81 includes at least a portion of the olefins (e.g., ethylene, propylene, butene) in the HC stream 74, and wherein the unreacted hydrocarbon stream 82 includes at least a portion of the unreacted hydrocarbons (e.g., the second hydrocarbon) in the HC stream 74. In an embodiment, the olefin stream 81 can include olefins, such as ethylene and / or propylene. In one embodiment, the unreacted hydrocarbon stream 82 can include methane, ethane, propane, etc., or a combination thereof. In some aspects, the unreacted hydrocarbon stream 82 can further include a trace of H2, CO2, CO, etc., or a combination thereof. The separator 800 may perform separation by any suitable separation technique, such as but not limited to distillation, cryogenic distillation, extractive distillation, selective adsorption, selective absorption, etc. or a combination thereof.

[0119] As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the composition of the cracking zone product stream 63, the composition of the HC stream 74, the composition of the unreacted hydrocarbon stream 82, and the composition of the olefin stream 81 all depend on a variety of factors, such as the composition of the cracking zone feed 60, the type of cracking zone 600, the operating conditions of the cracking zone 600, etc.

[0120] In an embodiment, the method of the present disclosure includes converting at least a portion of the HC stream 74, C 2+ At least a portion of stream 742, C 2+ At least a portion of stream 752 and / or at least a portion of unreacted hydrocarbon stream 82 is recycled to cracking zone 600 and / or CPO reaction zone 100 .

[0121] In an embodiment, at least a portion of the unreacted hydrocarbon stream 82 is introduced into the cracking zone 600, at least a portion of the unreacted hydrocarbon stream 82 is introduced into the CPO reaction zone 100, at least a portion of the unreacted hydrocarbon stream 82 is used as a fuel to heat the cracking zone 600 (e.g., introduced into a furnace within the common housing 150), and / or at least a portion of the unreacted hydrocarbon stream 82 is used as a fuel to heat the CPO reactant mixture 10.

[0122] In one embodiment, at least a portion of the HC stream 74 can be fed to the CPO reaction zone 100, for example, via the CPO reactant mixture 10. In one embodiment, at least a portion of the HC stream 74 can be used as a fuel (e.g., to preheat the CPO reactant mixture; to heat the cracking zone 600) and / or fed to the cracking zone 600. The HC stream 74 and can provide additional (e.g., supplemental) hydrocarbons to carry out the CPO reaction in the CPO reaction zone 100.

[0123] In embodiments where a portion of the unreacted hydrocarbons 82 and / or a portion of the HC stream 74 are introduced into the CPO reaction zone 100, the M ratio and / or the H2 / CO molar ratio of the syngas 15 can be greater than the M ratio and / or the H2 / CO molar ratio, respectively, of the syngas produced by an otherwise similar process in which a CPO reactant mixture without the portion of the unreacted hydrocarbons 82 and / or the HC stream 74 is fed to the CPO reaction zone 100. In embodiments, at least a portion of the hydrocarbon stream 74 and / or at least a portion of the unreacted hydrocarbons 82 can be used as a fuel (e.g., to preheat the CPO reactant mixture 10; to heat the cracking zone 600) and / or fed to the cracking zone 600.

[0124] In one embodiment, at least a portion of the unreacted hydrocarbons 82 and / or at least a portion of the HC stream 74 may be recycled to the cracking zone 600, for example, via the cracking zone feed 60. In one embodiment, at least a portion of the unreacted hydrocarbons 82 and / or at least a portion of the HC stream 74 may be used as a fuel, for example, for heating the cracking zone 600 and / or preheating the CPO reactant mixture 10. Since some crackers (e.g., the cracking zone 600) may have a maximum olefin feed limit (e.g., 5, 4, 3, 2, or 1 wt%), when at least a portion of the HC stream 74 is recycled to the cracking zone 600 via the cracking zone feed 60, at least a portion of the recycling is selected to maintain the olefin content of the cracking zone feed 60 below the maximum olefin feed limit.

[0125] In one embodiment, at least a portion of the H2 stream 73 may be contacted with at least a portion of the CPO reaction zone effluent syngas 15 to produce a hydrogen-enriched syngas 16, such as Figure 1 As shown, the H2 / CO molar ratio of the hydrogen-enriched syngas 16 is greater than the H2 / CO molar ratio of the CPO reaction zone effluent syngas 15. The M ratio of the hydrogen-enriched syngas 16 is greater than the M ratio of the CPO reaction zone effluent syngas 15.

[0126] The hydrogen-enriched synthetic gas 16 disclosed herein may be characterized by a H2 / CO molar ratio greater than about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, or about 2.5. In one embodiment, the hydrogen-enriched synthetic gas 16 disclosed herein may be characterized by an M ratio equal to or greater than about 1.8, or equal to or greater than about 2.0, or equal to or greater than about 2.1, or greater than about 2.2, or greater than about 2.3, or greater than about 2.4, or greater than about 2.5, or about 1.8 to about 2.5, or about 1.8 to about 2.4, or about 1.9 to about 2.3, or about 2.0 to about 2.2.

[0127] In one embodiment, the hydrogen-enriched syngas 16 disclosed herein may contain CO2 in an amount less than about 7 mol%, about 6 mol%, about 5 mol%, about 4 mol%, about 3 mol%, about 2 mol%, or about 1 mol%, or about 0.1 mol% to about 7 mol%, about 0.25 mol% to about 5 mol%, or about 0.5 mol% to about 3 mol%. The amount of CO2 in the hydrogen-enriched syngas 16 may be less than the amount of CO2 in the syngas 15. As will be appreciated by those skilled in the art, and with the aid of this disclosure, the H2 stream 73 recovered from the cracking zone 600 may have a reduced CO2 content compared to the effluent stream from the CPO reaction zone 100. Thus, combining the H2 stream 73 recovered from the cracking zone 600 with the effluent stream syngas 15 from the CPO reaction zone 100 may produce a stream having a reduced CO2 content compared to the effluent stream syngas 15 from the CPO reaction zone 100.

[0128] In one embodiment, the hydrogen-enriched syngas 16 disclosed herein may contain hydrocarbons in an amount less than about 5 mol%, about 4 mol%, about 3 mol%, about 2 mol%, about 1 mol%, about 0.1 mol%, or about 0.01 mol%. The amount of hydrocarbons in the hydrogen-enriched syngas 16 may be less than the amount of hydrocarbons in the CPO reaction zone effluent syngas 15. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the H2 stream 73 recovered from the cracking zone 600 may have a reduced hydrocarbon content compared to the effluent stream syngas 15 from the CPO reaction zone 100. Thus, combining the H2 stream 73 recovered from the cracking zone 600 with the effluent stream syngas 15 from the CPO reaction zone 100 may produce a hydrogen-enriched syngas stream 16 having a reduced hydrocarbon content compared to the effluent stream syngas 15 from the CPO reaction zone 100.

[0129] In embodiments where the syngas (eg, syngas 15; H2-enriched syngas 16) is characterized by an M ratio of about 1.8 to about 2.2, the syngas may be further used for methanol production.

[0130] In one embodiment, the method for producing methanol disclosed herein may include the step of introducing at least a portion of the syngas 15 and / or at least a portion of the hydrogen-enriched syngas 16 into a methanol reactor 200 to produce a methanol reactor effluent stream 30; wherein the methanol reactor effluent stream 30 comprises methanol, water, H2, CO, CO2, and hydrocarbons. The methanol reactor 200 may include any reactor suitable for a methanol synthesis reaction from CO and H2, such as a trickle bed reactor, a fluidized bed reactor, a slurry reactor, a loop reactor, a cooled multi-tubular reactor, the like, or a combination thereof.

[0131] Typically, CO and H2 can be converted into CH3OH, for example as shown in reaction equation (9):

[0132]

[0133] CO2 and H2 can also be converted into methanol, for example as shown in reaction equation (10):

[0134]

[0135] Without wishing to be bound by theory, the lower the CO2 content of the syngas, the lower the amount of water produced in the methanol reactor 200. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, the syngas produced by the SMR has a substantially higher H2 content (compared to the H2 content of the syngas produced by the CPO), and the syngas having an elevated H2 content can promote the conversion of CO2 to methanol (e.g., as shown in reaction equation (10)), which in turn can result in an increase in the water content in the crude methanol stream (e.g., crude methanol stream 40).

[0136] The synthesis of CH3OH from CO, CO2 and H2 is a catalytic process and is most commonly carried out in the presence of a copper-based catalyst. The methanol reactor 200 may include a methanol production catalyst, such as any suitable commercial catalyst for methanol synthesis. Non-limiting examples of methanol production catalysts suitable for use in the methanol reactor 200 of the present disclosure include Cu, Cu / ZnO, Cu / ThO2, Cu / Zn / Al2O3, Cu / ZnO / Al2O3, Cu / Zr, etc., or combinations thereof.

[0137] In one embodiment, the method for producing methanol disclosed herein may include the step of separating at least a portion of the methanol reactor effluent stream 30 into a crude methanol stream 40 and a vapor stream 50; wherein the crude methanol stream 40 comprises methanol and water; wherein the vapor stream 50 comprises H2, CO, CO2, and hydrocarbons (e.g., first hydrocarbons and / or second hydrocarbons). The methanol reactor effluent stream 30 may be separated into a crude methanol stream 40 and a vapor stream 50 in a gas-liquid separator 300 (e.g., a vapor-liquid separator, a flash drum, a knockout drum, a knockout drum, a compressor suction drum, etc.).

[0138] In one embodiment, the method for producing methanol disclosed herein may include a step of separating at least a portion of a crude methanol stream 40 into a methanol stream 45 and a water stream 46 in a distillation unit 400, wherein the distillation unit 400 includes one or more distillation columns. The water stream 46 comprises water and residual methanol. Generally, the one or more distillation columns may separate the components of the crude methanol stream 40 based on boiling point. As will be appreciated by those skilled in the art, and with the help of this disclosure, the higher the water content of the crude methanol stream 40, the more distillation columns are required to purify the methanol.

[0139] In one embodiment, methanol stream 45 may comprise methanol in an amount equal to or greater than about 95 wt.%, about 97.5 wt.%, about 99 wt.%, or about 99.9 wt.%, based on the total weight of methanol stream 45 .

[0140] In one embodiment, the method for producing methanol disclosed herein may include the step of separating at least a portion of a vapor stream 50 into an H2 stream 51 and a residual gas stream 52, wherein the H2 stream 51 comprises at least a portion of the H2 in the vapor stream 50, and wherein the residual gas stream 52 comprises CO, CO2, and hydrocarbons (e.g., first hydrocarbons and / or second hydrocarbons). The vapor stream 50 may be separated into the H2 stream 51 and the residual gas stream 52 in a first H2 recovery unit 500 (e.g., a PSA unit, a membrane separation unit, a cryogenic separation unit, the like, or a combination thereof). In some embodiments, at least a portion 63b of the cracking zone product stream 63 may be introduced into the first H2 recovery unit 500.

[0141] In one embodiment, the method for producing methanol disclosed herein may include recycling at least a portion 51a of the H2 stream 51 to the methanol reactor 200; for example, via the synthesis gas fed to the methanol reactor 200. In some aspects, at least a portion 51a of the H2 stream 51 may be contacted with at least a portion of the hydrogen-enriched syngas 16 to produce a methanol reactor feed stream 21, wherein at least a portion of the methanol reactor feed stream 21 may be introduced into the methanol reactor 200 to produce methanol. In such aspects, the methanol reactor feed stream 21 may be characterized by an M ratio of about 4 to about 17, or about 5 to about 15, or about 6 to about 12, or about 7 to about 10. In some embodiments, at least a portion of the residual gas stream 52 may be purified. In other embodiments, at least a portion of the residual gas stream 52 may be used as a fuel, such as for preheating the CPO reactant mixture 10, heating the cracking zone 600, or the like, or a combination thereof. In other embodiments, at least a portion 52a of the residual gas stream 52 may be fed to the CPO reaction zone 100. In other embodiments, at least a portion 52b of the residue gas stream 52 may be fed to the cracking zone 600 .

[0142] In one embodiment, the method for producing methanol and olefins (e.g., ethylene) disclosed herein may include the following steps: (a) feeding a catalytic partial oxidation (CPO) reactant mixture 10 to a CPO reaction zone 100; wherein the CPO reactant mixture comprises O2, a first hydrocarbon, and optionally steam; wherein the CPO reaction zone 100 comprises a CPO catalyst; wherein at least a portion of the CPO reactant mixture 10 reacts in the CPO reaction zone 100 under near-isothermal conditions by an exothermic CPO reaction to produce synthesis gas 15; wherein the near-isothermal conditions include a temperature variation of less than about ±100°C throughout the CPO reaction zone 100 and / or its catalyst bed; ℃, and wherein the catalyst bed comprises a CPO catalyst; wherein the synthesis gas 15 comprises H2, CO, CO2, water and unreacted first hydrocarbon, and wherein the synthesis gas 15 is characterized by an M ratio of the synthesis gas, wherein the M ratio is a molar ratio defined as (H2-CO2) / (CO+CO2); (b) feeding a cracking zone feed 60 to a cracking zone 600, wherein the cracking zone feed 60 comprises a second hydrocarbon (e.g., ethane); wherein at least a portion of the cracking zone feed 60 undergoes an endothermic cracking reaction in the cracking zone 600 to produce a cracking zone product stream 63; wherein the cracking zone product stream 63 comprises olefins (e.g., ethylene), H2 and unreacted second hydrocarbon (e.g., unreacted ethane); (c) cooling the CPO reaction zone 100; wherein cooling the CPO reaction zone 100 includes heating the cracking zone 600 by (e.g., indirect) heat transfer between the CPO reaction zone 100 and the thermal cracking zone 600 while cooling the CPO reaction zone 100; and wherein the heat transfer between the CPO reaction zone 100 and the cracking zone 600 provides near-isothermal conditions in the CPO reaction zone 100; (d) separating at least a portion of the cracking zone product stream 63 into an olefin stream 81 (e.g., an ethylene stream), an H2 stream 73, and unreacted ethane in a separation unit (e.g., a separation unit comprising a second H2 recovery unit 700 and / or a separator 800); (e) optionally contacting at least a portion of the H2 stream 73 with at least a portion of the synthesis gas 15 to produce a hydrogen-enriched syngas 16, wherein the hydrogen-enriched syngas 16 is characterized by an M ratio greater than the M ratio of the synthesis gas 15, and wherein the M ratio of the hydrogen-enriched syngas 16 is equal to or greater than about 1.7; (f) optionally recycling at least a portion of the unreacted hydrocarbon stream 82 (e.g., unreacted ethane) to the cracking zone 600 in step (b); and (g) introducing at least a portion of the synthesis gas 15 and / or at least a portion of the hydrogen-enriched syngas 16 into the methanol reactor 200 to produce methanol. In such an embodiment, the M ratio of the hydrogen-enriched syngas 16 can be equal to or greater than about 1.8, and the H2 / CO molar ratio of the hydrogen-enriched syngas 16 can be greater than about 2.0. In such an embodiment, the second hydrocarbon can include ethane, the cracking zone 600 can include an ethane cracker, and the olefin can include ethylene.

[0143] In one embodiment, the process for producing synthesis gas and olefins disclosed herein can advantageously exhibit improvements in one or more process characteristics compared to an otherwise similar process without integrating the CPO reaction zone with the cracking zone. The process disclosed herein can advantageously utilize the H2 stream 73 separated from the cracking zone product 63 to increase the H2 content of the CPO reaction zone effluent synthesis gas 15.

[0144] As will be appreciated by those skilled in the art, and with the aid of the present disclosure, because the CPO reaction is exothermic, very little heat supply in the form of fuel combustion (e.g., for preheating reactants in the reaction mixture supplied to the syngas generation portion) is required compared to conventional steam reforming. Therefore, the method for producing syngas disclosed herein can advantageously produce less CO2 through fuel combustion compared to steam reforming. In addition, the method disclosed herein utilizes at least a portion of the process heat from the CPO reaction zone 100 to heat the cracking zone 600, thereby preventing runaway temperatures in the CPO reaction zone 100 (e.g., in the CPO catalyst bed), which can cause catalyst deactivation. As will be appreciated by those skilled in the art, and with the aid of the present disclosure, operating the CPO reaction zone 100 at a relatively low C / O ratio (e.g., less than about 2:1) can result in runaway temperatures, and therefore removing heat from the CPO reaction zone 100 can advantageously enable the CPO reaction zone to be operated at a relatively low C / O ratio.

[0145] In one embodiment, at least a portion of the cracking zone product stream 63, the HC stream 74 and / or the unreacted hydrocarbon stream 82 can be advantageously mixed into the CPO reactant mixture 10 so that the H2 content of the resulting CPO reactant mixture 10 is less than about 20 mol%, or less than about 14 mol%, which allows the hydrocarbons therein to be used in the CPO reaction.

[0146] In one embodiment, an H2 separation unit (e.g., first H2 recovery unit 500) or a second H2 recovery unit 700 present in the methanol loop may be used to separate an H2 stream 73 from the cracking zone product stream 63. The H2 streams (51, 73) recovered from the H2 separation units 500, 700 may be advantageously recycled (51a, 73) to the methanol loop inlet, and unconverted hydrocarbons (e.g., in the residual gas stream 52, the HC stream 74, and / or the unreacted hydrocarbon stream 82) may be advantageously recycled (e.g., via line 52a, a line fluidly connecting the HC stream 74 to the CPO reaction zone 100, a line fluidly connecting the unreacted hydrocarbon stream 82 to the CPO reaction zone 100) to the CPO reaction zone 100.

[0147] In one embodiment, the method for producing synthesis gas and olefins disclosed herein may advantageously include introducing at least a portion 63b of the compressed cracking zone product stream 63 into the first H2 recovery unit 500 of the methanol loop. In such an embodiment, the method for producing synthesis gas and olefins disclosed herein may advantageously include introducing at least a portion 52a of the residual gas stream 52 of a portion of the purified stream from the first H2 recovery unit 500 into the CPO reaction zone 100 through the CPO reactant mixture 10. In such an embodiment, the hydrocarbons in the cracking zone product stream 63 will accumulate less or not in the methanol loop, thereby reducing the size of the methanol loop equipment. In such an embodiment, the hydrocarbons in the cracking zone product stream 63 can be advantageously converted into synthesis gas in the CPO reaction zone 100. In such an embodiment, the second H2 recovery unit (e.g., the second H2 recovery unit 700) can be advantageously eliminated. By reading this disclosure, those skilled in the art can clearly understand other advantages of the method for producing synthesis gas, olefins and / or methanol disclosed herein.

[0148] Example

[0149] Having generally described the subject matter, the following examples are given as specific embodiments of the present disclosure and are used to demonstrate its practice and advantages. It should be understood that the examples are given by way of illustration and are not intended to limit the description of the claims in any way.

[0150] Example 1

[0151] Table 1 shows the yields of cracking light hydrocarbon feedstocks by conventional cracking processes (eg, gas cracking processes).

[0152]

[0153] Although preferred embodiments of the present invention have been shown and described, those skilled in the art may modify them without departing from the teachings of the present disclosure. The embodiments described herein are exemplary only and are not intended to be limiting. Various modifications and variations of the invention disclosed herein are possible and are within the scope of the present invention.

[0154] Once the above disclosure is fully understood, many other modifications, equivalents and alternatives will become apparent to those skilled in the art. Where applicable, the following claims are intended to be interpreted as including all such modifications, equivalents and alternatives. Therefore, the scope of protection is not limited by the above description, but only by the appended claims, which include all equivalents of the claimed subject matter. Each claim is incorporated into the description as an embodiment of the present invention. Therefore, the claims are further descriptions and are a supplement to the detailed description of the present invention. The disclosures of all patents, patent applications and publications cited herein are incorporated herein by reference.

Claims

1. A method for producing synthesis gas and olefins, the method comprising: (a) feeding a catalytic partial oxidation (CPO) reactant mixture to a CPO reaction zone; wherein the CPO reactant mixture comprises oxygen, a first hydrocarbon, and optionally steam; wherein at least a portion of the CPO reactant mixture reacts in a CPO reaction zone via an exothermic CPO reaction to produce synthesis gas; wherein the CPO reaction zone comprises a CPO catalyst; wherein the synthesis gas comprises hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water, and unreacted first hydrocarbon, and wherein the synthesis gas is characterized by an M ratio of the synthesis gas, wherein the M ratio is a molar ratio defined as (H2-CO2) / (CO+CO2); (b) feeding a cracking zone feed to a cracking zone, wherein the cracking zone feed comprises a second hydrocarbon; wherein at least a portion of the second hydrocarbon undergoes an endothermic cracking reaction in the cracking zone to produce a cracking zone product stream; wherein the first hydrocarbon and the second hydrocarbon are the same or different; wherein the cracking zone product stream comprises olefins, hydrogen, and unreacted second hydrocarbon; and (c) cooling the CPO reaction zone; wherein cooling the CPO reaction zone comprises heating the cracking zone while cooling the CPO reaction zone by heat transfer between the CPO reaction zone and the cracking zone, wherein the process further comprises the steps of: (1) separating at least a portion of the cracking zone product stream into a hydrogen stream and a hydrocarbon stream, wherein the hydrocarbon stream comprises olefins and unreacted hydrocarbons; (2) contacting at least a portion of the hydrogen feed stream with at least a portion of the synthesis gas to produce a hydrogen-enriched syngas, wherein the hydrogen-enriched syngas is characterized by an M ratio that is greater than the M ratio of the synthesis gas, and wherein the M ratio of the hydrogen-enriched syngas is equal to or greater than 1.7; (3) introducing at least a portion of the synthesis gas and at least a portion of the hydrogen-enriched syngas into a methanol reactor to produce methanol.

2. The process of claim 1 wherein a common housing comprises both the CPO reaction zone and the cracking zone.

3. The method of claim 2, wherein the common enclosure further comprises a furnace zone; wherein the fuel stream is combusted in the furnace zone to provide additional heat for the endothermic cracking reaction.

4. The method of claim 2, wherein the common housing further comprises a cracking reactor disposed therein, wherein the cracking reactor is characterized by a cracking reactor outer surface and a cracking reactor inner surface, and wherein the cracking reactor inner surface defines a cracking zone.

5. The method of claim 4, wherein heating the cracking zone comprises heating the feed to the cracking zone in a cracking reactor disposed within a common housing.

6. The method of claim 4, wherein the cracking reactor comprises one or more tubes disposed within a common shell; wherein heating the cracking zone comprises heating the second hydrocarbon within one or more tubes disposed within the common shell; wherein the CPO catalyst is disposed within the common shell; and wherein the CPO catalyst is located above the one or more tubes, below the one or more tubes, around the one or more tubes, on the one or more tubes, or a combination thereof.

7. The method according to claim 4: wherein the outer surface of the cracking reactor does not contact the CPO catalyst; wherein the CPO reaction zone and the cracking zone are adjacent to each other, and wherein the CPO reaction zone and the cracking zone do not spatially overlap; wherein at least a portion of the outer surface of the cracking reactor contacts the CPO catalyst; wherein the common housing comprises a CPO catalyst bed disposed therein, wherein the CPO catalyst bed comprises a CPO catalyst, and wherein at least a portion of the cracking reactor is disposed within the CPO catalyst bed; and / or The CPO catalyst layer coats at least a portion of the outer surface of the cracking reactor.

8. The method of claim 4, wherein the second hydrocarbon comprises ethane, propane, butane, naphtha, optionally methane, or a combination thereof; and wherein the olefin comprises ethylene.

9. The method of claim 1, wherein the CPO reaction zone is characterized by at least one CPO operating parameter selected from the group consisting of: a CPO feed temperature of 25°C to 600°C; a CPO effluent temperature of 300°C to 1600°C; a CPO pressure of 1 bar to 90 bar; a CPO contact time of 0.001 milliseconds (ms) to 5 seconds (s); a carbon to oxygen (C / O) molar ratio in the CPO reactant mixture of 0.5:1 to 3:1, wherein the C / O molar ratio refers to the total number of moles of hydrocarbon carbon (C) in the reactant mixture divided by the total number of moles of oxygen (O2) in the reactant mixture; a steam to carbon (S / C) molar ratio in the CPO reactant mixture of 0.01:1 to less than 2.4:1, wherein the S / C molar ratio refers to the total number of moles of water (H2O) in the reactant mixture divided by the total number of moles of hydrocarbon carbon (C) in the reactant mixture; and combinations thereof.

10. The method of claim 1, wherein heat transfer between the CPO reaction zone and the cracking zone provides near-isothermal conditions in the CPO reaction zone, wherein the near-isothermal conditions include a temperature variation of less than ±100°C throughout the CPO reaction zone and / or its catalyst bed, and wherein the catalyst bed comprises a CPO catalyst.

11. The method of claim 1, wherein the first hydrocarbon and / or the second hydrocarbon comprises methane, ethane, propane, butane, naphtha, natural gas, natural gas liquids, associated gas, wellhead gas, enriched gas, paraffin, shale gas, shale liquids, fluid catalytic cracking (FCC) tail gas, refinery process gas, flue gas, fuel gas from a fuel gas header, or a combination thereof.

12. The method of claim 1, further comprising: (4) separating at least a portion of the hydrocarbon stream into an olefin stream and an unreacted hydrocarbon stream, wherein the olefin stream comprises at least a portion of the olefins in the hydrocarbon stream, and wherein the unreacted hydrocarbon stream comprises at least a portion of the unreacted hydrocarbons in the hydrocarbon stream; and (5) optionally recycling at least a portion of the hydrocarbon stream and / or at least a portion of the unreacted hydrocarbon stream to the cracking zone in step (b) and / or the CPO reaction zone in step (a).

13. A method for producing methanol and ethylene, the method comprising: (a) feeding a catalytic partial oxidation (CPO) reactant mixture to a CPO reaction zone; wherein the CPO reactant mixture comprises oxygen, a hydrocarbon, and optionally steam; wherein the CPO reaction zone comprises a CPO catalyst; wherein at least a portion of the CPO reactant mixture reacts in the CPO reaction zone under near-isothermal conditions via an exothermic CPO reaction to produce synthesis gas; wherein the near-isothermal conditions include a temperature variation of less than ±100° C. throughout the CPO reaction zone and / or on its catalyst bed, and wherein the catalyst bed comprises a CPO catalyst; wherein the synthesis gas comprises hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water, and unreacted hydrocarbons, and wherein the synthesis gas is characterized by an M ratio of the synthesis gas, wherein the M ratio is a molar ratio defined as (H2-CO2) / (CO+CO2); (b) feeding a cracking zone feed to a cracking zone, wherein the cracking zone feed comprises ethane; wherein at least a portion of the ethane undergoes an endothermic cracking reaction in the cracking zone to produce a cracking zone product stream; wherein the cracking zone product stream comprises ethylene, hydrogen, and unreacted ethane; (c) cooling the CPO reaction zone; wherein cooling the CPO reaction zone comprises heating the cracking zone while cooling the CPO reaction zone by heat transfer between the CPO reaction zone and the cracking zone; and wherein the heat transfer between the CPO reaction zone and the cracking zone provides near isothermal conditions in the CPO reaction zone; (d) separating at least a portion of the cracking zone product stream into an ethylene stream, a hydrogen stream, and an unreacted ethane stream in a separation unit; (e) contacting at least a portion of the hydrogen stream with at least a portion of the syngas to produce a hydrogen enriched syngas, wherein the hydrogen enriched syngas is characterized by an M ratio greater than the M ratio of the syngas, and wherein the M ratio of the hydrogen enriched syngas is equal to or greater than 1.7; (f) optionally recycling at least a portion of the unreacted ethane stream to the cracking zone in step (b); and (g) introducing at least a portion of the synthesis gas and at least a portion of the hydrogen-enriched synthesis gas into a methanol reactor to produce methanol.

14. The method of claim 13, wherein the common housing comprises both a CPO reaction zone and a cracking zone; wherein the common housing further comprises a furnace zone; wherein a fuel stream is optionally combusted in the furnace zone to provide additional heat for the endothermic cracking reaction; wherein the housing further comprises a cracking reactor disposed therein, wherein the cracking reactor is characterized by a cracking reactor outer surface and a cracking reactor inner surface, and wherein the cracking reactor inner surface defines the cracking zone.

15. The method of claim 14, wherein the cracking reactor comprises one or more tubes disposed within a common shell; wherein heating the cracking zone comprises heating ethane within one or more tubes disposed within the common shell; wherein the CPO catalyst is disposed within the common shell; and wherein the CPO catalyst is located above the one or more tubes, below the one or more tubes, around the one or more tubes, on the one or more tubes, or a combination thereof.

16. The method of claim 13, wherein the separation unit comprises a pressure swing adsorption (PSA) unit, a membrane separation unit, a cryogenic separation unit, an oil scrubber separation unit, a size exclusion unit, or a combination thereof.

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