CN111116298A - Separation method and device for preparing olefin from synthesis gas - Google Patents
Separation method and device for preparing olefin from synthesis gas Download PDFInfo
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- CN111116298A CN111116298A CN201811275715.2A CN201811275715A CN111116298A CN 111116298 A CN111116298 A CN 111116298A CN 201811275715 A CN201811275715 A CN 201811275715A CN 111116298 A CN111116298 A CN 111116298A
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- 238000000926 separation method Methods 0.000 title claims abstract description 114
- 230000015572 biosynthetic process Effects 0.000 title claims abstract description 84
- 238000003786 synthesis reaction Methods 0.000 title claims abstract description 83
- 150000001336 alkenes Chemical class 0.000 title claims abstract description 81
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 title claims abstract description 64
- 239000000463 material Substances 0.000 claims abstract description 135
- 239000007789 gas Substances 0.000 claims abstract description 128
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 122
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 82
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims abstract description 79
- 239000005977 Ethylene Substances 0.000 claims abstract description 79
- 238000011084 recovery Methods 0.000 claims abstract description 69
- 230000002745 absorbent Effects 0.000 claims abstract description 67
- 239000002250 absorbent Substances 0.000 claims abstract description 67
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 61
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 61
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 47
- 239000001257 hydrogen Substances 0.000 claims abstract description 46
- 229910002091 carbon monoxide Inorganic materials 0.000 claims abstract description 45
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 44
- 238000006356 dehydrogenation reaction Methods 0.000 claims abstract description 29
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 24
- 238000005262 decarbonization Methods 0.000 claims abstract description 16
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 claims description 56
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 claims description 56
- 229930195733 hydrocarbon Natural products 0.000 claims description 24
- 238000001179 sorption measurement Methods 0.000 claims description 22
- 150000002431 hydrogen Chemical class 0.000 claims description 18
- 239000004215 Carbon black (E152) Substances 0.000 claims description 17
- -1 olefin hydrocarbon Chemical class 0.000 claims description 11
- 238000002360 preparation method Methods 0.000 claims description 11
- BVKZGUZCCUSVTD-UHFFFAOYSA-M Bicarbonate Chemical compound OC([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-M 0.000 claims description 7
- 238000010521 absorption reaction Methods 0.000 claims description 7
- 239000012528 membrane Substances 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 238000003795 desorption Methods 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 25
- 238000006243 chemical reaction Methods 0.000 abstract description 22
- 238000005265 energy consumption Methods 0.000 abstract description 16
- 238000005516 engineering process Methods 0.000 abstract description 12
- 230000008901 benefit Effects 0.000 abstract description 7
- 238000011027 product recovery Methods 0.000 abstract description 4
- 239000000047 product Substances 0.000 description 134
- 230000000052 comparative effect Effects 0.000 description 34
- 229910052799 carbon Inorganic materials 0.000 description 25
- 150000002430 hydrocarbons Chemical class 0.000 description 22
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 20
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 12
- 238000005261 decarburization Methods 0.000 description 11
- 239000003054 catalyst Substances 0.000 description 9
- CRVGTESFCCXCTH-UHFFFAOYSA-N methyl diethanolamine Chemical compound OCCN(C)CCO CRVGTESFCCXCTH-UHFFFAOYSA-N 0.000 description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 8
- 239000003507 refrigerant Substances 0.000 description 7
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 6
- 239000003245 coal Substances 0.000 description 6
- 239000001294 propane Substances 0.000 description 6
- 238000001816 cooling Methods 0.000 description 5
- 239000003208 petroleum Substances 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 description 4
- 238000005336 cracking Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 4
- 229910000029 sodium carbonate Inorganic materials 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 230000018109 developmental process Effects 0.000 description 3
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 description 3
- 239000003345 natural gas Substances 0.000 description 3
- 238000000746 purification Methods 0.000 description 3
- 239000012264 purified product Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 150000001993 dienes Chemical class 0.000 description 2
- LVTYICIALWPMFW-UHFFFAOYSA-N diisopropanolamine Chemical compound CC(O)CNCC(C)O LVTYICIALWPMFW-UHFFFAOYSA-N 0.000 description 2
- 229940043276 diisopropanolamine Drugs 0.000 description 2
- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910000027 potassium carbonate Inorganic materials 0.000 description 2
- 230000008929 regeneration Effects 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- PVXVWWANJIWJOO-UHFFFAOYSA-N 1-(1,3-benzodioxol-5-yl)-N-ethylpropan-2-amine Chemical compound CCNC(C)CC1=CC=C2OCOC2=C1 PVXVWWANJIWJOO-UHFFFAOYSA-N 0.000 description 1
- QMMZSJPSPRTHGB-UHFFFAOYSA-N MDEA Natural products CC(C)CCCCC=CCC=CC(O)=O QMMZSJPSPRTHGB-UHFFFAOYSA-N 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- VNWKTOKETHGBQD-YPZZEJLDSA-N carbane Chemical compound [10CH4] VNWKTOKETHGBQD-YPZZEJLDSA-N 0.000 description 1
- 239000011203 carbon fibre reinforced carbon Substances 0.000 description 1
- 239000003034 coal gas Substances 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000004230 steam cracking Methods 0.000 description 1
- 125000000383 tetramethylene group Chemical group [H]C([H])([*:1])C([H])([H])C([H])([H])C([H])([H])[*:2] 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/11—Purification; Separation; Use of additives by absorption, i.e. purification or separation of gaseous hydrocarbons with the aid of liquids
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/005—Processes comprising at least two steps in series
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/04—Purification; Separation; Use of additives by distillation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/12—Purification; Separation; Use of additives by adsorption, i.e. purification or separation of hydrocarbons with the aid of solids, e.g. with ion-exchangers
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Water Supply & Treatment (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a separation method and a device for preparing olefin from synthesis gas, which mainly solve the problems that the subsequent separation process is influenced by a large amount of unconverted synthesis gas contained in product gas due to low conversion rate in the reaction process of preparing olefin from synthesis gas, the efficiency of carbon monoxide and hydrogen removing equipment in the prior separation technology is low, and cryogenic separation needs to be adopted in the prior separation technology, and adopts the following steps: separating the product gas stream into a carbon dioxide stream and a decarbonized stream in a decarbonization zone; the decarbonized material flow is separated into a component material flow of C2 and below and a component material flow of C2 and above through a rough separation tower; c2 and the following component flows are separated into a recycle flow mainly containing carbon monoxide and hydrogen and a crude methane flow through a dehydrogenation zone; the crude methane material flow is sent to the lower part of the ethylene recovery tower, the methane material flow is obtained by separating the top of the tower, the rich absorbent material flow rich in ethylene is obtained at the bottom of the tower, and the method can be used for the separation process of preparing olefin products from synthesis gas and has the advantages of high equipment efficiency, high product recovery rate, high product purity and low energy consumption in the separation process.
Description
Technical Field
The invention relates to a separation method and a separation device for preparing olefin from synthesis gas, in particular to a separation method and a separation device for preparing olefin from synthesis gas by a one-step method.
Technical Field
Olefins, particularly ethylene, propylene and butylene, are important basic chemical raw materials, and the demand for them has been increasing in recent years. Generally, olefins are derived primarily from petroleum processing. With the increasing scarcity of petroleum resources, the cost of producing ethylene and propylene from petroleum resources is increasing, and the development of the technology for producing olefin from non-petroleum resources such as coal or natural gas and the like attracts more and more attention at home and abroad. The method for preparing low-carbon olefin by using coal, natural gas and the like as raw materials generally comprises the steps of converting the coal and the natural gas into synthesis gas and then preparing the low-carbon olefin from the synthesis gas. In the long run, the method has important strategic significance on the adjustment of energy structures in China and the reduction of dependence on petroleum resources.
The current mature technical route for preparing olefin from coal comprises four core technologies of coal gasification, synthesis gas purification, methanol synthesis and preparing olefin from methanol. Firstly, gasifying coal to prepare synthesis gas, then transforming the synthesis gas, purifying the transformed synthesis gas, finally preparing the purified synthesis gas into crude methanol and rectifying to finally produce qualified methanol. The main problems of coal-to-olefin are as follows: long technical route, large equipment quantity, large equipment investment, large raw material and energy consumption and high water consumption.
The direct preparation of olefin from synthesis gas avoids the synthesis and purification procedures of intermediate products, has shorter process route and reduces investment cost and operation cost. However, the process for directly preparing olefin from synthesis gas has not yet realized industrialized operation, and the main research is still focused on the development of the catalyst, but the research on the aspects of the development of the process flow, the design of the product separation scheme and the like is very deficient.
From the patent and literature methods, the direct preparation of olefins from synthesis gas is a Fischer-Tropsch (F-T) synthesis process, the product is distributed in a wide carbon number range, the product gas at the reaction outlet contains a large amount of unconverted synthesis gas, and the selectivity of low-carbon olefins is low, so that the separation difficulty is increased, and the improvement of economic benefit is greatly influenced.
CN 102666441a discloses a supported iron-based catalyst for use in the production of lower olefins from synthesis gas by a process for producing lower olefins from a feed stream comprising carbon monoxide and hydrogen, for example by the Fischer-Tropsch (Fischer-Tropsch) process, at a temperature above 270 ℃ and not above 500 ℃, the iron-containing particles of the catalyst composition having an average particle size below 20m, preferably below 10 nm.
CN 102971277A discloses the production of light olefins such as C from synthesis gas using an iron based catalyst, the step of contacting the synthesis gas with the iron based catalyst at a temperature in the range of 250 to 350 ℃ and a pressure in the range of 10 to 40 bar (bar)2～4A process for producing olefins. H2 of syngas: the molar ratio of CO is in the range of 1.5 to 2.5.
CN 103664447A discloses a catalyst composition for preparing olefin from synthesis gas, which comprises CO and H with a molar ratio of 0.8-2.22The mixed gas is used as a raw material, and the reaction temperature is 250-350 ℃, the reaction pressure is 0.5-2.5 MPa, and the volume space velocity is 1000-4000 hours-1Under the condition of (1), the catalyst is in contact reaction with a catalyst to generate olefin, wherein the catalyst comprises the following components, by weight, 1-20 parts of a shell selected from one of ZSM-5 or β zeolite and 80-99 parts of an inner core.
CN108017481 discloses a separation method of a product gas for directly preparing low-carbon olefin from synthesis gas, which comprises the steps of cooling and drying the product gas of a reaction for directly preparing olefin from synthesis gas, and then feeding the cooled and dried product gas into a product gas purification unit to remove a carbon dioxide component in the product gas, so as to obtain a purified product gas; the purified product gas enters a synthesis gas primary recovery unit, and primary recovery is carried out on unconverted synthesis gas in the synthesis gas primary recovery unit; the product gas after primary recovery enters a synthesis gas secondary recovery unit for secondary recovery; the tower bottom material after secondary recovery enters a carbon dioxide and carbon three and heavy component separation unit to separate a carbon dioxide component from the carbon three and the heavy component; feeding the materials at the top of the tower of the carbon two and carbon three and heavy component separation unit into an ethylene rectification unit to obtain an ethylene product; the tower bottom material enters a carbon three and heavy component separation unit to separate carbon three components from carbon four and heavy components; and the tower top material of the carbon three and heavy component separation unit enters a propylene rectification unit to obtain a propylene product, and the tower bottom material enters a debutaning unit to obtain a carbon four product and a gasoline product. The method sends all the product gas into the carbon dioxide removing area, the dehydrogenation gas area and the carbon monoxide removing area, reduces the efficiency of the separation equipment, and increases the size and the investment of the equipment. In addition, after the high-temperature product gas is cooled, the high-temperature product gas is sent to a carbon dioxide removal area, a dehydrogenation gas area and a carbon monoxide removal area, and then the high-temperature product gas is sequentially separated, so that the energy loss is large. The method also needs to cool the pressure swing adsorption product gas to 125 ℃ below zero for cryogenic separation, needs to adopt ethylene refrigerant or binary refrigerant for cooling, needs to add an expensive set of refrigeration equipment for factories without ethylene steam cracking devices, and is not cost-effective in investment and land occupation.
In summary, in order to accelerate the industrialization process of directly preparing olefin from syngas, it is very necessary to provide a separation method with convenient operation and simple process, which can smoothly complete the separation of each component in the product gas at the outlet of the reaction for directly preparing olefin from syngas. Meanwhile, the composition distribution characteristics of each component in the product gas are considered, and a proper separation technology is selected to ensure the quality of the low-carbon olefin product.
The invention provides a separation method for preparing olefin from synthesis gas, which aims to solve the problems in a targeted manner.
Disclosure of Invention
The invention relates to a separation method for preparing olefin from synthesis gas, which mainly solves the problems that the subsequent separation process is influenced by a large amount of unconverted synthesis gas contained in product gas due to low conversion rate in the reaction process of preparing olefin from synthesis gas, the efficiency of carbon monoxide and hydrogen removing equipment in the prior separation technology is low, and cryogenic separation is needed in the prior separation technology.
In order to solve the problems, the technical scheme adopted by the invention is as follows:
a) separating the product gas stream into a carbon dioxide stream comprising primarily carbon dioxide components and a decarbonated stream in a decarbonation zone;
b) separating the decarbonized material flow into a C2 material flow mainly containing carbon monoxide, hydrogen, ethylene and methane and a component material flow below the C2 material flow and a component material flow above the C2 material flow through a rough separation tower;
c) c2 and the following component flows are separated into a recycle flow mainly containing carbon monoxide and hydrogen and a crude methane flow through a dehydrogenation zone;
d) feeding the crude methane material flow into the lower part of an ethylene recovery tower, feeding the crude methane material flow into an absorbent material flow from the upper part of the ethylene recovery tower to be contacted in the tower, separating the tower top to obtain a methane material flow, obtaining a rich absorbent material flow rich in ethylene from the tower bottom, and feeding the rich absorbent material flow and the C2 and the above component material flow into a product separation area to be used as feeding materials.
In the technical scheme of the invention, at least part of the product gas stream comes from a synthesis gas olefin preparation reactor; optionally, at least part of the recycle stream obtained in step c) is returned to the synthesis gas to olefins reactor.
In the technical scheme of the invention, the product separation zone separates to obtain an olefin product and a C4 and above component stream.
In the technical scheme of the invention, the C4 and above component material flows are separated in an absorbent tower to obtain an absorbent material flow and a gasoline product material flow.
In the technical scheme of the invention, the absorbent material flow is sent to the upper part of the ethylene recovery tower.
In the technical scheme of the invention, the carbon dioxide is separated from the decarbonization zone by an absorption and desorption method.
In the technical scheme of the invention, the decarbonization area generates bicarbonate ions.
In the technical scheme of the invention, carbon monoxide or/and hydrogen is separated from the dehydrogenation zone by adopting one or at least one of a pressure swing adsorption separation method, a temperature swing adsorption separation method and a membrane separation method.
In the technical scheme of the invention, the temperature of the decarbonized material flow is lower than or equal to minus 15 ℃, preferably lower than or equal to minus 17 ℃.
In the technical scheme of the invention, the pressure of the decarbonized material flow is more than or equal to 2.4MPaG, and preferably more than or equal to 2.5 MPaG.
A separation unit for producing olefins from synthesis gas, comprising:
a decarbonization zone; configured to receive a product gas stream, emit a carbon dioxide stream and a decarbonated stream;
roughly dividing the tower; configured to receive the decarbonized stream, an overhead discharge of a stream of components C2 and below, and a kettle discharge of a stream of components C2 and above;
a dehydrogenation zone; configured to receive said C2 and component streams therefrom, to discharge a recycle stream and a crude methane stream;
an ethylene recovery column; configured to receive the crude methane stream at a lower portion, an absorbent stream at an upper portion, a methane stream at an overhead portion, and a rich absorbent stream at a bottom portion of the column.
In the technical scheme of the invention, the separation device also comprises a product separation area; configured to receive the stream of C2 and above components and the rich absorbent stream and discharge an olefin product and a stream of C4 and above components.
In the technical scheme of the invention, the separation device also comprises an absorbent tower; configured to receive the C4 and above component streams, an overhead absorbent stream, and a bottoms gasoline product stream.
In the technical scheme of the invention, the decarbonization zone comprises an absorption tower and a resolving tower.
In the technical scheme of the invention, the dehydrogenation zone comprises one or at least one of a pressure swing adsorption device, a temperature swing adsorption device and a membrane separation device.
In the technical scheme of the invention, the product separation zone comprises a deethanizer, an ethylene rectifying tower, a depropanizer and a propylene rectifying tower.
In the technical scheme of the invention, the product separation zone is preferably separated according to a sequential separation process to obtain an olefin product, namely the C2 and above component material flow and rich absorbent material flow are firstly sent into a deethanizer, the C2 component material flow obtained at the tower top is sent into an ethylene rectifying tower, the C3 and above component material flow obtained at the tower bottom is sent into a depropanizer, the C3 component material flow obtained at the tower top is sent into a propylene rectifying tower, the C4 and above component material flow obtained at the tower bottom is sent into an absorbent tower, and the ethylene product material flow and the propylene product material flow are respectively obtained at the ethylene rectifying tower and the propylene rectifying tower.
In the technical scheme of the invention, C4 component material flow is obtained at the top of the absorbent tower, C5 and above component material flow is obtained at the bottom of the tower and is used as gasoline product material flow, and at least part of C4 component material flow is used as absorbent material flow and is sent to the upper part of an ethylene recovery tower.
In another technical scheme of the invention, a C4-C5 mixed material flow is obtained at the tower top of the absorbent tower, a material flow of C6 and above is obtained at the tower bottom and is used as a gasoline product material flow, and at least part of the C4-C5 mixed material flow is used as an absorbent material flow and is sent to the upper part of the ethylene recovery tower.
In another technical scheme of the invention, a C4-C6 mixed material flow is obtained at the tower top of the absorbent tower, a material flow of C7 and above is obtained at the tower bottom and is used as a gasoline product material flow, and at least part of the C4-C6 mixed material flow is used as an absorbent material flow and is sent to the upper part of the ethylene recovery tower.
In the technical scheme of the invention, the C4 component material flow is sent to the olefin cracking device to crack the olefin component into the crude propylene material flow mainly containing ethylene and propylene, and the crude propylene material flow is sent to the depropanizing tower to be used as a feed.
In another technical scheme of the invention, the mixed material flow of C4-C5 is sent to an olefin cracking device to crack olefin components into a crude propylene material flow mainly containing ethylene and propylene, and the crude propylene material flow is sent to a depropanizing tower to be used as a feed.
In another technical scheme of the invention, the mixed material flow of C4-C6 is sent to an olefin cracking device to crack olefin components into a crude propylene material flow mainly containing ethylene and propylene, and the crude propylene material flow is sent to a depropanizing tower to be used as a feed.
In the above technical solution, the product gas stream comprises carbon dioxide, carbon monoxide, hydrogen and mixed hydrocarbons.
In the above technical solution, preferably, the product gas stream contains, by weight, 10% to 40% of carbon dioxide, 1% to 5% of hydrogen, 30% to 70% of carbon monoxide, and 10% to 40% of mixed hydrocarbons.
In the above technical solution, preferably, the product gas stream contains 15% to 35% of carbon dioxide by weight percentage.
In the above technical solution, preferably, the mixed hydrocarbon stream contains at least 60% by weight of C2-C4 hydrocarbons.
In the above technical solution, more preferably, the mixed hydrocarbon stream contains at least 70% by weight of C2-C4 hydrocarbons.
In the above technical solution, most preferably, the mixed hydrocarbon stream contains at least 75% by weight of C2-C4 hydrocarbons.
In the technical scheme of the invention, at least 70% of the circulating stream is returned to the synthesis gas olefin preparation reactor.
In the technical scheme of the invention, preferably, at least 90% of the circulating stream is returned to the synthesis gas olefin preparation reactor.
In the technical scheme of the invention, more preferably, all the recycle stream is returned to the synthesis gas olefin preparation reactor.
In the technical scheme of the invention, the decarbonized material flow mainly contains carbon monoxide, hydrogen, methane, ethylene, ethane, propylene, propane, C4 and above hydrocarbons.
According to the technical scheme, when the carbon dioxide absorbent in the decarbonization region adopts potassium carbonate and sodium carbonate of the same series as the potassium carbonate as the absorbent, carbon dioxide is firstly hydrolyzed to generate hydrogen ions and bicarbonate ions, the hydrogen ions and the carbonate ions react to generate the bicarbonate ions, namely, carbon dioxide, water and carbonate react to generate bicarbonate, so that the effect of absorbing the carbon dioxide is achieved.
In another technical scheme of the invention, when the carbon dioxide absorbent in the decarbonization region adopts methyldiethanolamine and the ethanolamine, diethanolamine and diisopropanolamine which are the same series as the methyldiethanolamine as the absorbent, carbon dioxide is firstly hydrolyzed to generate hydrogen ions and bicarbonate ions, the hydrogen ions react with alcohol amine substances to generate protonated alcohol amine, namely, the carbon dioxide, water and the alcohol amine react to generate the bicarbonate ions and the protonated alcohol amine, so that the effect of absorbing the carbon dioxide is achieved.
The inventor considers that the energy is saved when the methyldiethanolamine and the ethanolamine, diethanolamine and diisopropanolamine in the same series are used as the absorbent through screening and simulation of the carbon dioxide absorbent in the decarbonization zone.
In the technical scheme of the invention, the temperature of the decarbonized material flow needs to meet the condition of being lower than minus 15 ℃, the process requirements can be met only by adopting common propylene refrigerant, and the deep cooling by adopting ethylene refrigerant is not needed, so that the investment is saved, the requirements on equipment materials are reduced on the other hand, and the safety is improved.
According to the technical scheme, after carbon dioxide is removed from product gas, the obtained decarbonized material flow is subjected to primary separation in a rough separation tower after being cooled slightly (lower than 15 ℃) to obtain C2 and the following component material flows at the tower top, the C2 and the following component material flows are sent to a dehydrogenation area to remove a circulating material flow containing carbon monoxide and hydrogen, the circulating material flow is sent to an ethylene recovery tower, at least one part of C4-C6 mixed material flow is used as an absorbent, a methane material flow is obtained at the tower top of the ethylene recovery tower, and a rich absorbent material flow obtained at the tower bottom and the C2 and the above component material flows are sent to a product separation area for subsequent. The resulting recycle stream containing carbon monoxide and hydrogen is at least partially returned to the synthesis gas to olefins reactor. In the separation process of the technical scheme, only a part of product gas (C2 and the following component streams) is sent to the dehydrogenation zone, so that the utilization efficiency of equipment in the dehydrogenation zone can be improved, the size of the equipment is reduced, and the investment cost is reduced; the recycle stream is returned to the reactor for preparing olefin from synthesis gas, so that the product yield is improved, the unit consumption of the device is reduced, and the device benefit is increased.
In the technical scheme of the invention, the temperature of the decarbonized material flow needs to meet the condition of being lower than or equal to minus 15 ℃, the process requirements can be met only by adopting common propylene refrigerant, and ethylene refrigerant is not needed for deep cooling, so that on one hand, the investment is saved, on the other hand, the requirement on equipment materials is reduced, and the safety is improved.
According to the technical scheme, through the separation process of preferentially selecting the synthesis gas to prepare the olefin, carbon dioxide is removed, then the material flow containing C2 and the following components is separated from the material flow containing C2 and the above components, and the separation is gradually carried out according to a reasonable sequence by preferentially selecting the process conditions of a decarbonization area and a dehydrogenation area, so that the unreacted raw materials are fully utilized, more diene products are obtained under the conditions of only adopting propylene refrigerant, low energy consumption, low investment and high efficiency, and a good technical effect is achieved; when the absorbent is preferred, the energy consumption can be further reduced, and a better technical effect can be achieved.
The technical scheme adopted by the invention is applied to the separation process for preparing olefin from synthesis gas, particularly the technology for preparing olefin from synthesis gas by a one-step method, has greater advantages in the aspects of yield of diolefin, material consumption, energy consumption, wastewater yield and investment progression compared with the existing coal chemical technology, and particularly has more obvious advantages in the preferred scheme of the technical scheme.
The embodiment and the comparative example show that the technical scheme adopted by the invention is applied to the separation process for preparing olefin from synthesis gas, compared with the comparative example technology, the separation process has the advantages of high carbon dioxide removal rate, high carbon monoxide and hydrogen recovery rate, high yield and high recovery rate of ethylene products and propylene products, solves the problems that the subsequent separation process is influenced by a large amount of unconverted synthesis gas contained in product gas due to low conversion rate in the reaction process for preparing olefin from synthesis gas, and the equipment efficiency of carbon dioxide, carbon monoxide and hydrogen removal in the existing cryogenic separation technology is low, and has the advantages of high equipment efficiency, high product recovery rate, high product purity and low energy consumption in the separation process.
All publications, patent applications, patents, and other references mentioned in this specification are herein incorporated by reference in their entirety. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present specification, including definitions, will control.
When the specification concludes with claims with the heading "known to those skilled in the art", "prior art", or the like, to derive materials, substances, methods, procedures, devices, or components, etc., it is intended that the subject matter derived from the heading encompass those conventionally used in the art at the time of filing this application, but also include those that are not currently in use, but would become known in the art to be suitable for a similar purpose.
In the context of the present specification, anything or things which are not mentioned, except where explicitly stated, are directly applicable to those known in the art without any changes. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or concepts resulting therefrom are considered part of the original disclosure or original disclosure of the invention, and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such a combination to be clearly unreasonable.
The present invention will be further illustrated by the following examples, but is not limited to these examples.
Drawings
FIG. 1 provides a separation method for preparing olefin from synthesis gas.
FIG. 2 is a schematic view of the overall process of the separation method according to the present invention.
FIG. 3 is a schematic flow diagram of a separation process described in a comparative example.
FIG. 1 depicts the following:
101 product gas stream
102 is a carbon dioxide stream
103 is a decarbonated stream
104 is C2 and the following component streams
105 is a stream of components C2 and above
106 is a recycle stream
107 is a crude methane stream
108 is a methane stream
109 is a rich absorbent stream
120 is an absorbent stream
11 is a decarburization zone
12 is a rough separation tower
13 is a dehydrogenation zone
14 is an ethylene recovery column
In FIG. 1, a product gas stream 101 is separated in a decarbonization zone 11 into a carbon dioxide stream 102 comprising mainly carbon dioxide components and a decarbonized stream 103; the decarbonized material flow 103 is separated into a C2 material flow mainly containing carbon monoxide, hydrogen, ethylene and methane and a lower component material flow 104 and a C2 and higher component material flow 105 through a rough separation tower 12; c2 and the following component stream 104 are separated in dehydrogenation zone 13 into a recycle stream 106 comprising primarily carbon monoxide and hydrogen and a crude methane stream 107; the crude methane stream is sent to the lower part of an ethylene recovery tower 14 and is contacted with an absorbent stream 120 sent to the upper part in the tower, the methane stream 108 is obtained by separating at the top of the tower, a rich absorbent stream 109 rich in ethylene is obtained at the bottom of the tower, and the rich absorbent stream 109 and a C2 and the above component stream 105 are sent to a product separation zone to be used as feed materials
Fig. 2 is a schematic diagram of a full-flow process of the separation method provided by the invention, and for comparison with a comparative example, the separation method in fig. 1 is further expanded to obtain a full-flow separation method of an ethylene product and a propylene product.
FIG. 2 depicts the following:
101 product gas stream
102 is a carbon dioxide stream
103 is a decarbonated stream
104 is C2 and the following component streams
105 is a stream of components C2 and above
106 is a recycle stream
107 is a crude methane stream
108 is a methane stream
109 is a rich absorbent stream
110 is a C2 component stream
111C 3 and higher component stream
112 is an ethylene product stream
113 is an ethane stream
114 is a C3 component stream
115 is a stream of components C4 and above
116 is a propylene product stream
117 is a propane stream
118 is an absorbent stream (C4 component stream)
119 is a gasoline product stream (C5 and above component stream)
120 is an absorbent stream
11 is a decarburization zone
12 is a rough separation tower
13 is a dehydrogenation zone
14 is an ethylene recovery column
15 is a deethanizer
16 is an ethylene separation column
17 is a depropanizer
18 is a propylene separating column
19 is an absorbent tower (debutanizer)
In FIG. 2, a product gas stream 101 is separated in a decarbonization zone 11 into a carbon dioxide stream 102 comprising mainly carbon dioxide components and a decarbonized stream 103; the decarbonized material flow 103 is separated into a C2 material flow mainly containing carbon monoxide, hydrogen, ethylene and methane and a lower component material flow 104 and a C2 and higher component material flow 105 through a rough separation tower 12; c2 and the following component stream 104 are separated in dehydrogenation zone 13 into a recycle stream 106 comprising primarily carbon monoxide and hydrogen and a crude methane stream 107; at least a portion of the recycle stream 106 is returned to the syngas to olefins reactor; feeding the crude methane stream 107 into the lower part of the ethylene recovery tower 14, contacting the crude methane stream with the absorbent stream 120 fed into the upper part in the tower, separating the top of the tower to obtain a methane stream 108, obtaining an ethylene-rich absorbent stream 109 at the bottom of the tower, and feeding the absorbent stream 109, the C2 and the component stream 105 to a deethanizer 15 as a feed; the deethanizer 15 separates to obtain a C2 component stream 110 and a C3 and above component stream 111, the C2 component stream 110 further separates to obtain an ethylene product stream 112 and an ethane stream 113 in the ethylene separation tower 16, the C3 and above component stream 111 is sent to the depropanizer 17 to separate to obtain a C3 component stream 114 and a C4 and above component stream 115, the C3 component stream 114 further separates to obtain a propylene product stream 116 and a propane stream 117 in the propylene separation tower 18; c4 and above component stream 115 is sent to a debutanizer 19 to be separated into a C4 component stream 118 and a C5 and above component stream 119, and the C4 component is at least partially sent to the upper part of an ethylene recovery tower 14 as an absorbent stream 120 to recover the ethylene component in the crude methane stream 107.
FIG. 3 illustrates in labeled form:
201 is product gas
202 is decarbonized product gas
203 is carbon dioxide
204 is unconverted synthesis gas
205 is pressure swing adsorption product gas
206 is the first unconverted synthesis gas and methane
207 is a second unconverted synthesis gas and methane
208 is an ethylene product
209 is an ethane product
210 is a propylene product
211 is a propane product
212 is a carbon four product
213 is a gasoline product.
21 is a dryer
22 is an absorption tower
23 is a regeneration tower
24 is a pressure swing adsorption device
25 is a carbon-separating tank
26 is a demethanizer
27 is a deethanizer
28 is an ethylene rectifying tower
29 is a depropanizer
30 is a propylene rectifying tower
31 is a debutanizer.
In fig. 3, a product gas 201 enters a dryer 21 to remove a small amount of moisture, then enters an absorption tower 22 to perform mass transfer and heat transfer with an MDEA solvent, a carbon dioxide component in the gas is absorbed, then a carbon dioxide material stream 203 is released from the top of a regeneration tower 23, a purified product gas, namely a decarbonized product gas 202, is led out from the top of the absorption tower 22 and sent to a pressure swing adsorption device 24, the content of H2 and CO components in the product gas subjected to pressure swing adsorption is greatly reduced, the pressure swing adsorption product gas 205 is subjected to cryogenic cooling and then sent to a carbon-first separation tank 25 and a demethanizer 26 to separate unconverted synthesis gas and methane, and the remaining mixed hydrocarbons enter a deethanizer 27 to complete the separation of carbon dioxide, carbon three and heavy components. The materials at the top of the deethanizer 27 mainly comprise ethylene and a small amount of ethane, the materials are rectified and separated by the ethylene rectifying tower 28, a polymer-grade ethylene product 208 is obtained at the top of the tower, an ethane material flow is obtained at the bottom of the tower, the materials at the bottom of the deethanizer 27 mainly comprise carbon three and heavy components, the separation of the carbon three and the heavy components is completed by the depropanizer 29, the materials at the top of the depropanizer 29 mainly comprise propylene and a small amount of propane, the materials are rectified and separated by the propylene rectifying tower 30, a polymer-grade propylene product 210 is obtained at the top of the tower, and a propane material flow is obtained at the bottom of the tower; the tower bottom material composition of the depropanizing tower 29 is mainly carbon four and heavy components, and the separation of the carbon four and the heavy component gasoline is completed through the debutanizing tower 31 to obtain a carbon four product 212 and a gasoline product 213.
Detailed Description
By taking a product gas stream with the flow rate of 800000 kgh as a reference and adopting the technical scheme of the technology and the technical scheme of the comparative example, the mixed hydrocarbon material is cooled to below 15 ℃ below zero in the heat exchange zone of the technical scheme of the invention, and the product gas is cooled to below 100 ℃ below zero in the technical scheme of the comparative example, so that the carbon dioxide removal rate, the carbon monoxide and hydrogen recovery rate, the yield and recovery rate of the ethylene product and the propylene product, and the energy consumption are compared.
[ example 1 ]
The product stream obtained from the reaction zone comprises: 25.00 percent of carbon dioxide, 3.40 percent of hydrogen, 46.40 percent of carbon monoxide and 15.70 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, adopting methyldiethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning 76.5 percent of circulating material flow to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was cooled to 29 ℃ at zero temperature and a pressure of 2.51 MPaG.
The carbon dioxide removal rate is 98.64 percent, the carbon monoxide recovery rate is 99.00 percent, the hydrogen recovery rate is 98.20 percent, the ethylene product yield is 2.63 percent higher than that of the technical scheme of the comparative example, the recovery rate is 97.29 percent, the propylene product yield is 2.68 percent higher than that of the technical scheme of the comparative example, the recovery rate is 99.84 percent, and the energy consumption is 1.90 percent less than that of the technical scheme of the comparative example.
[ example 2 ]
The product stream obtained from the reaction zone comprises: 25.00 percent of carbon dioxide, 3.40 percent of hydrogen, 46.40 percent of carbon monoxide and 15.70 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, adopting methyldiethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning 86.5 percent of circulating material flow to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonized stream was at a temperature of 26 ℃ below zero and a pressure of 2.60 MPaG.
The carbon dioxide removal rate is 98.63%, the carbon monoxide recovery rate is 98.99%, the hydrogen recovery rate is 98.19%, the ethylene product yield is 2.97% higher than that of the technical scheme of the comparative example, the recovery rate is 97.39%, the propylene product yield is 3.03% higher than that of the technical scheme of the comparative example, the recovery rate is 99.87%, and the energy consumption is 1.89% lower than that of the technical scheme of the comparative example.
[ example 3 ]
The product stream obtained from the reaction zone comprises: 25.00 percent of carbon dioxide, 3.40 percent of hydrogen, 46.40 percent of carbon monoxide and 15.70 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, adopting methyldiethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning 96.5 percent of circulating material flow to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was at a temperature of 23 ℃ C. and a pressure of 2.70 MPaG.
The carbon dioxide removal rate is 98.62 percent, the carbon monoxide recovery rate is 98.98 percent, the hydrogen recovery rate is 98.19 percent, the ethylene product yield is 3.32 percent higher than that of the technical scheme of the comparative example, the recovery rate is 97.49 percent, the propylene product yield is 3.38 percent higher than that of the technical scheme of the comparative example, the recovery rate is 99.90 percent, and the energy consumption is 1.88 percent less than that of the technical scheme of the comparative example.
[ example 4 ]
The product stream obtained from the reaction zone comprises: 25.00 percent of carbon dioxide, 3.40 percent of hydrogen, 46.40 percent of carbon monoxide and 15.70 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, adopting methyldiethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning all circulating material flows to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was cooled to 20 ℃ at zero and a pressure of 2.8 MPaG.
The carbon dioxide removal rate is 98.60%, the carbon monoxide recovery rate is 98.97%, the hydrogen recovery rate is 98.17%, the ethylene product yield is 3.46% higher than that of the technical scheme of the comparative example, the recovery rate is 97.59%, the propylene product yield is 3.53% higher than that of the technical scheme of the comparative example, the recovery rate is 99.93%, and the energy consumption is 1.87% lower than that of the technical scheme of the comparative example.
[ example 5 ]
The product stream obtained from the reaction zone comprises: 20.00 percent of carbon dioxide, 3.05 percent of hydrogen, 40.35 percent of carbon monoxide and 27.1 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 1, adopting methyldiethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning all circulating material flows to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was at a temperature of 17.5 ℃ C. and a pressure of 2.9 MPaG.
The carbon dioxide removal rate is 98.60%, the carbon monoxide recovery rate is 98.98%, the hydrogen recovery rate is 98.18%, the ethylene product yield is 5.97% higher than that of the technical scheme of the comparative example, the recovery rate is 97.59%, the propylene product yield is 6.09% higher than that of the technical scheme of the comparative example, the recovery rate is 99.93%, and the energy consumption is 1.91% lower than that of the technical scheme of the comparative example.
[ example 6 ]
The product stream obtained from the reaction zone comprises: 20.00 percent of carbon dioxide, 3.05 percent of hydrogen, 40.35 percent of carbon monoxide and 27.1 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 1, adopting diethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning all circulating material flows to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was at a temperature of 17.5 ℃ C. and a pressure of 2.9 MPaG.
The carbon dioxide removal rate is 98.60%, the carbon monoxide recovery rate is 98.98%, the hydrogen recovery rate is 98.18%, the ethylene product yield is 5.97% higher than that of the technical scheme of the comparative example, the recovery rate is 97.59%, the propylene product yield is 6.09% higher than that of the technical scheme of the comparative example, the recovery rate is 99.93%, and the energy consumption is 1.91% lower than that of the technical scheme of the comparative example.
[ example 7 ]
The product stream obtained from the reaction zone comprises: 20.00 percent of carbon dioxide, 3.05 percent of hydrogen, 40.35 percent of carbon monoxide and 27.1 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 1, adopting sodium carbonate as an absorbent in a decarburization area, adopting a temperature swing adsorption separation method in a dehydrogenation area, returning all circulating material flows to a synthesis gas olefin preparation reactor, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was at a temperature of 17.5 ℃ C. and a pressure of 2.9 MPaG.
The carbon dioxide removal rate is 98.58%, the carbon monoxide recovery rate is 98.98%, the hydrogen recovery rate is 98.18%, the ethylene product yield is 5.97% higher than that of the technical scheme of the comparative example, the recovery rate is 97.59%, the propylene product yield is 6.09% higher than that of the technical scheme of the comparative example, the recovery rate is 99.93%, and the energy consumption is 1.89% lower than that of the technical scheme of the comparative example.
[ example 8 ]
The product stream obtained from the reaction zone comprises: 20.00 percent of carbon dioxide, 3.05 percent of hydrogen, 40.35 percent of carbon monoxide and 27.1 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, adopting sodium carbonate as an absorbent in a decarburization area, adopting a membrane separation method in a dehydrogenation area, returning all the circulating material flow to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The decarbonated stream was at a temperature of 17.5 ℃ C. and a pressure of 2.9 MPaG.
The carbon dioxide removal rate is 98.58%, the carbon monoxide recovery rate is 98.99%, the hydrogen recovery rate is 98.17%, the ethylene product yield is 5.97% higher than that of the technical scheme of the comparative example, the recovery rate is 97.59%, the propylene product yield is 6.09% higher than that of the technical scheme of the comparative example, the recovery rate is 99.93%, and the energy consumption is 1.90% lower than that of the technical scheme of the comparative example.
[ example 9 ]
The product stream obtained from the reaction zone comprises: 20.00 percent of carbon dioxide, 3.05 percent of hydrogen, 40.35 percent of carbon monoxide and 27.1 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, and the difference is that C4 and above component material flows are sent into an absorbent tower to be separated to obtain absorbent material flows containing four to six carbon components at the tower top, gasoline product material flows containing seven or above carbon components at the tower bottom, the absorbent material flows can be sent into an olefin cracking device to crack olefin components into crude propylene material flows mainly containing ethylene and propylene, the crude propylene material flows are sent into a deethanizer as feed, meanwhile, part of the mixed carbon four material flows are sent into an ethylene recovery tower, and the obtained rich absorbent material flows are sent into a deethanizer as feed. The decarbonization zone adopts sodium carbonate as an absorbent, the dehydrogenation zone adopts a membrane separation method, all the circulating material flow returns to a synthesis gas olefin preparation reactor, and ethylene products and propylene products are obtained through separation.
The decarbonated stream was at a temperature of 17.5 ℃ C. and a pressure of 2.9 MPaG.
The carbon dioxide removal rate is 98.59 percent, the carbon monoxide recovery rate is 98.99 percent, the hydrogen recovery rate is 98.17 percent, the ethylene product yield is 9.88 percent higher than that of the technical scheme of the comparative example, the recovery rate is 97.59 percent, the propylene product yield is 10.02 percent higher than that of the technical scheme of the comparative example, the recovery rate is 99.93 percent, and the energy consumption is 2.58 percent less than that of the technical scheme of the comparative example.
[ COMPARATIVE EXAMPLE 1 ]
The product stream obtained from the reaction zone comprises: 25.00 percent of carbon dioxide, 3.40 percent of hydrogen, 46.40 percent of carbon monoxide and 15.70 percent of mixed hydrocarbon, adopting the technical scheme shown in figure 2, adopting methyldiethanolamine as an absorbent in a decarburization area, adopting a pressure swing adsorption separation method in a dehydrogenation area, returning all circulating material flows to a reactor for preparing olefin from synthesis gas, and separating to obtain an ethylene product and a propylene product.
The low temperature mixed hydrocarbon stream was 125 deg.C below zero and at a pressure of 3.5 MPaG.
The carbon dioxide removal rate is 98.40%, the carbon monoxide recovery rate is 98.60%, the hydrogen recovery rate is 98.00%, the ethylene product recovery rate is 97.2%, and the propylene product recovery rate is 99.80%.
Claims (16)
1. A separation method for preparing olefin by synthesis gas comprises the following steps:
a) separating the product gas stream into a carbon dioxide stream comprising primarily carbon dioxide components and a decarbonated stream in a decarbonation zone;
b) separating the decarbonized material flow into a C2 material flow mainly containing carbon monoxide, hydrogen, ethylene and methane and a component material flow below the C2 material flow and a component material flow above the C2 material flow through a rough separation tower;
c) c2 and the following component flows are separated into a recycle flow mainly containing carbon monoxide and hydrogen and a crude methane flow through a dehydrogenation zone;
d) feeding the crude methane material flow into the lower part of an ethylene recovery tower, feeding the crude methane material flow into an absorbent material flow from the upper part of the ethylene recovery tower to be contacted in the tower, separating the tower top to obtain a methane material flow, obtaining a rich absorbent material flow rich in ethylene from the tower bottom, and feeding the rich absorbent material flow and the C2 and the above component material flow into a product separation area to be used as feeding materials.
2. The separation process for synthesis gas to olefins according to claim 1, characterized in that the product gas stream is at least partially derived from a synthesis gas to olefins reactor; optionally, at least part of the recycle stream obtained in step c) is returned to the synthesis gas to olefins reactor.
3. The separation method for preparing olefin by synthesis gas according to claim 1, characterized in that the product separation zone separates the olefin product and the component stream of C4 and above.
4. The separation method for preparing olefin hydrocarbon from synthesis gas according to claim 3, characterized in that the absorbent material flow obtained by separating the component material flow of C4 and above and the gasoline product material flow are separated in an absorbent tower.
5. The separation process for olefins from synthesis gas according to claim 3, characterized in that the absorbent stream is sent to the upper part of the ethylene recovery column.
6. The separation method for preparing olefin hydrocarbon from synthesis gas according to claim 1, characterized in that the carbon dioxide is separated from the decarbonization zone by absorption and desorption.
7. A separation process for olefins from synthesis gas according to claim 4, characterized in that the decarbonization zone has the formation of bicarbonate ions.
8. The separation method for preparing olefin from synthesis gas according to claim 1, characterized in that carbon monoxide or/and hydrogen is separated in the dehydrogenation zone by one or at least one of a pressure swing adsorption separation method, a temperature swing adsorption separation method and a membrane separation method.
9. The separation process for the preparation of olefins from synthesis gas according to claim 1, characterized in that the decarbonated stream temperature is lower than or equal to-15 ℃, preferably lower than or equal to-17 ℃.
10. The separation process for the production of olefins from synthesis gas according to claim 1, characterized in that the pressure of the decarbonated stream is greater than or equal to 2.4MPaG, preferably greater than or equal to 2.5 MPaG.
11. A separation unit for producing olefins from synthesis gas, comprising:
1) a decarbonization zone; configured to receive a product gas stream, emit a carbon dioxide stream and a decarbonated stream;
2) roughly dividing the tower; configured to receive the decarbonized stream, an overhead discharge of a stream of components C2 and below, and a kettle discharge of a stream of components C2 and above;
3) a dehydrogenation zone; configured to receive said C2 and component streams therefrom, to discharge a recycle stream and a crude methane stream;
4) an ethylene recovery column; configured to receive the crude methane stream at a lower portion, an absorbent stream at an upper portion, a methane stream at an overhead portion, and a rich absorbent stream at a bottom portion of the column.
12. The separation device for the production of olefins from synthesis gas according to claim 11, characterized in that the separation device further comprises a product separation zone; configured to receive the stream of C2 and above components and the rich absorbent stream and discharge an olefin product and a stream of C4 and above components.
13. The separation unit for the production of olefins from synthesis gas according to claim 11, characterized in that the separation unit further comprises an absorbent column; configured to receive the C4 and above component streams, an overhead absorbent stream, and a bottoms gasoline product stream.
14. The separation plant for the preparation of olefins from synthesis gas according to claim 11, characterized in that the decarbonization section comprises an absorption column and a stripper column.
15. The separation device for producing olefin from synthesis gas according to claim 11, wherein the dehydrogenation zone comprises one or at least one of a pressure swing adsorption device, a temperature swing adsorption device, and a membrane separation device.
16. The separation plant for the preparation of olefins from synthesis gas according to claim 11, characterized in that the product separation zone comprises a deethanizer, an ethylene rectifier, a depropanizer and a propylene rectifier.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101559320A (en) * | 2009-04-15 | 2009-10-21 | 上海惠生化工工程有限公司 | Separation method of Fischer-Tropsch synthesis gas by combining rectification and solvent absorption |
| CN102304010A (en) * | 2011-07-11 | 2012-01-04 | 中国天辰工程有限公司 | Method for separating low carbon olefin mixed gas by rectifying and absorbing |
| CN103242123A (en) * | 2012-02-10 | 2013-08-14 | 中国石油化工股份有限公司 | Method for separating low-carbon olefin gas |
| CN103626898A (en) * | 2012-08-24 | 2014-03-12 | 中国石油化工集团公司 | Method of recovering light hydrocarbon from byproduct gas of Fischer-Tropsch synthesis |
| US20140128486A1 (en) * | 2012-06-25 | 2014-05-08 | Saudi Basic Industries Corporation | Process for Producing Ethylene and Propylene from Syngas |
| CN106588526A (en) * | 2015-10-20 | 2017-04-26 | 中国石油化工股份有限公司 | System for preparing olefin by taking coal and refinery dry gas as raw materials and method for preparing olefin |
-
2018
- 2018-10-30 CN CN201811275715.2A patent/CN111116298A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101559320A (en) * | 2009-04-15 | 2009-10-21 | 上海惠生化工工程有限公司 | Separation method of Fischer-Tropsch synthesis gas by combining rectification and solvent absorption |
| CN102304010A (en) * | 2011-07-11 | 2012-01-04 | 中国天辰工程有限公司 | Method for separating low carbon olefin mixed gas by rectifying and absorbing |
| CN103242123A (en) * | 2012-02-10 | 2013-08-14 | 中国石油化工股份有限公司 | Method for separating low-carbon olefin gas |
| US20140128486A1 (en) * | 2012-06-25 | 2014-05-08 | Saudi Basic Industries Corporation | Process for Producing Ethylene and Propylene from Syngas |
| CN103626898A (en) * | 2012-08-24 | 2014-03-12 | 中国石油化工集团公司 | Method of recovering light hydrocarbon from byproduct gas of Fischer-Tropsch synthesis |
| CN106588526A (en) * | 2015-10-20 | 2017-04-26 | 中国石油化工股份有限公司 | System for preparing olefin by taking coal and refinery dry gas as raw materials and method for preparing olefin |
Non-Patent Citations (1)
| Title |
|---|
| 杨学萍等: "合成气直接制低碳烯烃技术进展与经济性分析", 《化工进展》 * |
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