CN113620839A - Method and device for producing acrylonitrile - Google Patents
Method and device for producing acrylonitrile Download PDFInfo
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- CN113620839A CN113620839A CN202010388160.3A CN202010388160A CN113620839A CN 113620839 A CN113620839 A CN 113620839A CN 202010388160 A CN202010388160 A CN 202010388160A CN 113620839 A CN113620839 A CN 113620839A
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- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 title claims abstract description 85
- 238000000034 method Methods 0.000 title claims abstract description 22
- 238000011084 recovery Methods 0.000 claims abstract description 111
- 238000001704 evaporation Methods 0.000 claims abstract description 91
- 230000008020 evaporation Effects 0.000 claims abstract description 91
- 239000000463 material Substances 0.000 claims abstract description 78
- 239000007789 gas Substances 0.000 claims abstract description 55
- 239000007788 liquid Substances 0.000 claims abstract description 44
- 239000002351 wastewater Substances 0.000 claims abstract description 31
- 238000007255 decyanation reaction Methods 0.000 claims abstract description 14
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000000926 separation method Methods 0.000 claims abstract description 10
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 claims description 74
- 239000000047 product Substances 0.000 claims description 26
- 238000010521 absorption reaction Methods 0.000 claims description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 20
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 18
- 238000004519 manufacturing process Methods 0.000 claims description 12
- 229910021529 ammonia Inorganic materials 0.000 claims description 9
- 239000001257 hydrogen Substances 0.000 claims description 7
- 229910052739 hydrogen Inorganic materials 0.000 claims description 7
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 claims description 6
- 239000007795 chemical reaction product Substances 0.000 claims description 6
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 claims description 6
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 claims description 5
- 238000010791 quenching Methods 0.000 claims description 5
- 230000000171 quenching effect Effects 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 4
- 238000001816 cooling Methods 0.000 claims description 3
- 238000007599 discharging Methods 0.000 claims description 3
- 239000001294 propane Substances 0.000 claims description 3
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 60
- 239000000243 solution Substances 0.000 description 32
- 239000012071 phase Substances 0.000 description 30
- HGINCPLSRVDWNT-UHFFFAOYSA-N Acrolein Chemical compound C=CC=O HGINCPLSRVDWNT-UHFFFAOYSA-N 0.000 description 6
- 238000010992 reflux Methods 0.000 description 5
- 238000002347 injection Methods 0.000 description 4
- 239000007924 injection Substances 0.000 description 4
- 238000007670 refining Methods 0.000 description 4
- 239000002250 absorbent Substances 0.000 description 3
- 230000002745 absorbent Effects 0.000 description 3
- 239000008346 aqueous phase Substances 0.000 description 3
- 229910002091 carbon monoxide Inorganic materials 0.000 description 3
- 239000012043 crude product Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000012074 organic phase Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- AQGDXJQRVOCUQX-UHFFFAOYSA-N N.[S] Chemical compound N.[S] AQGDXJQRVOCUQX-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 2
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 2
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- MWFMGBPGAXYFAR-UHFFFAOYSA-N 2-hydroxy-2-methylpropanenitrile Chemical compound CC(C)(O)C#N MWFMGBPGAXYFAR-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 238000010793 Steam injection (oil industry) Methods 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000012495 reaction gas Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 229920003051 synthetic elastomer Polymers 0.000 description 1
- 239000012209 synthetic fiber Substances 0.000 description 1
- 229920002994 synthetic fiber Polymers 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 239000005061 synthetic rubber Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/32—Separation; Purification; Stabilisation; Use of additives
- C07C253/34—Separation; Purification
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/06—Flash distillation
- B01D3/065—Multiple-effect flash distillation (more than two traps)
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/24—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/24—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons
- C07C253/26—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons containing carbon-to-carbon multiple bonds, e.g. unsaturated aldehydes
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a method and a device for producing acrylonitrile, wherein the method comprises the following steps: (1) carrying out steam stripping separation on the rich liquid containing the acrylonitrile in a recovery tower, obtaining a gas phase material flow containing the acrylonitrile at the top of the recovery tower, and obtaining a high-temperature barren liquid basically not containing the acrylonitrile at the bottom of the recovery tower; (2) and (3) carrying out flash evaporation on the high-temperature barren liquor which is obtained at the bottom of the recovery tower and is basically free of acrylonitrile, and taking steam obtained by flash evaporation as a heat source of a hot end. The method is characterized in that high-temperature barren liquor which is basically free of acrylonitrile and is obtained at the bottom of a recovery tower is subjected to flash evaporation, steam obtained by flash evaporation is pressurized and then is used as a heat source at least at one position of the recovery tower, a waste water evaporator, a decyanation hydrogen hydride tower, a finished product tower and the like, and the method and the device can effectively recover and utilize low-grade heat sources, save energy and reduce consumption.
Description
Technical Field
The invention belongs to the technical field of acrylonitrile, and particularly relates to a method and a device for producing acrylonitrile.
Background
Acrylonitrile is one of three major derivatives of propylene, and plays an important role in the field of materials such as synthetic resins, synthetic fibers, synthetic rubbers and the like. In industry, acrylonitrile is produced by a propylene ammoxidation method, and a production device comprises a reaction unit, a recovery unit, a refining unit and a wastewater treatment unit. Propylene, ammonia and air are fed into a fluidized bed reactor in proportion, and are reacted to generate acrylonitrile under the action of a catalyst, and byproducts such as acetonitrile, water, acrolein, hydrogen cyanide, acrylic acid and the like are generated; cooling the reacted gas phase, removing heavy components and waste catalyst, neutralizing unreacted ammonia with sulfuric acid, and sending the ammonia-sulfur solution to a ammonia-sulfur recovery device; the gas after ammonia removal is sent to an absorption section, and water is used as an absorbent to absorb acrylonitrile, acetonitrile, hydrogen cyanide and other organic matters in the gas, namely CO and CO which are not absorbed2、N2、O2And unreacted hydrocarbon is treated by a tail gas treatment system, and the absorption liquid enters a refining section. In the refining section, acetonitrile in the absorption liquid is separated by a recovery tower and sent to an acetonitrile device, hydrogen cyanide separated by a decyanation hydrogen tower is sent to an acetone cyanohydrin device, finally, crude acrylonitrile enters a finished product tower for refining, the bottom liquid part of the recovery tower is sent to a waste water evaporator for pretreatment and then sent to sewage treatment, and the rest part is cooled and then returned to the absorption tower as absorbent barren liquid for reuse. Because the solubility of acrylonitrile in water is limited, the concentration of acrylonitrile in absorbent (water) rich solution generated after reaction gas is absorbed by water is about 4-5 wt%, each ton of acrylonitrile needs more than 20 tons of water for absorption, and low-temperature absorption and high-temperature desorption recovery lead the absorption tower and the recovery tower to become the energy-consuming concentrated area of acrylonitrile device.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a method and a device for producing acrylonitrile, wherein the method comprises the steps of carrying out flash evaporation on high-temperature barren liquor which is obtained at the bottom of a recovery tower and is basically free of acrylonitrile, and pressurizing steam obtained by flash evaporation to be used as a heat source of a heat-requiring end (such as at least one position of the recovery tower, a waste water evaporator, a decyanation hydrogen tower and a finished product tower).
The purpose of the invention is realized by the following technical scheme:
a process for the production of acrylonitrile, said process comprising the steps of:
(1) carrying out steam stripping separation on the rich liquid containing the acrylonitrile in a recovery tower, obtaining a gas phase material flow containing the acrylonitrile at the top of the recovery tower, and obtaining a high-temperature barren liquid basically not containing the acrylonitrile at the bottom of the recovery tower;
(2) and (3) carrying out flash evaporation on the high-temperature barren liquor which is obtained at the bottom of the recovery tower and is basically free of acrylonitrile, and taking steam obtained by flash evaporation as a heat source of a hot end.
According to the invention, the hot end comprises at least one of a recovery tower, a waste water evaporator, a decyanation hydrogen chloride tower, a finished product tower and the like.
When the hot end required is the recovery tower, steam obtained by flash evaporation can enter the bottom of the recovery tower to directly supply heat, and/or enter a reboiler at the bottom of the recovery tower to indirectly supply heat as a heat source.
The waste water evaporator is used for distilling and dehydrating the discharged barren liquor to obtain condensate water and concentrated waste water, the condensate water is recycled, and the concentrated waste water is further treated, wherein the discharged barren liquor is from liquid after flash evaporation or from bottom liquid of a recovery tower.
Wherein, the hydrogen cyanide removal tower is used for separating the top of the recovery tower to obtain a gas phase material flow containing acrylonitrile and obtain crude hydrogen cyanide and acrylonitrile, and the hot end required is, for example, a reboiler at the bottom of the hydrogen cyanide removal tower.
The finished product tower is used for separating acrylonitrile crude products to prepare acrylonitrile products, and the hot end required is, for example, a reboiler at the bottom of the finished product tower.
According to the invention, in the step (1), the rich liquid containing acrylonitrile is obtained by the following method:
cooling the gas phase material flow of the reaction product obtained by propylene and/or propane ammoxidation, sending the cooled gas phase material flow into a quenching and ammonia removal section, contacting the gas phase material flow of the reaction product subjected to quenching and ammonia removal treatment with water in an absorption tower, and obtaining the pregnant solution containing acrylonitrile at the bottom of the absorption tower.
Wherein the contact temperature is 20-50 ℃, and the contact pressure is 100-150 kPa.
Wherein the gas phase material of the reaction product comprises acrylonitrile, hydrogen cyanide, acetonitrile, propylene, propane, acrolein, carbon monoxide, carbon dioxide, ammonia, oxygen, nitrogen, argon and the like.
Wherein the temperature of the reaction product gas phase material flow after the quenching and ammonia removal treatment is 30-70 ℃, and the pressure is 120-150 kPa.
In the step (1), the content of acrylonitrile in the rich liquid containing acrylonitrile is 2 to 10 wt%, such as 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%.
In step (1), the recovery column is a recovery column known in the art.
In the step (1), the pressure of the stripping separation is 100-250kPa, and the temperature is 70-140 ℃.
In the step (1), the content of acrylonitrile in the gas phase material flow containing acrylonitrile obtained from the top of the recovery tower is 70-80 wt%; the content of acrylonitrile in the high-temperature barren solution which is basically not containing acrylonitrile and is obtained at the bottom of the recovery tower is less than 100 ppm.
In the step (1), the temperature of the gas phase material flow containing the acrylonitrile obtained at the top of the recovery tower is 50-90 ℃, and the pressure is 110-120 kPa; the temperature of the high-temperature barren solution which is basically free of acrylonitrile and is obtained at the bottom of the recovery tower is 90-130 ℃, and the pressure is 110-350 kPa.
According to the invention, in step (2), the flashing is carried out at least at one pressure level, preferably at least at two pressure levels, for example at one, two, three, four or more pressure levels.
In the step (2), the gas-phase stream obtained by each stage of flash evaporation is pressurized, for example, the gas-phase stream obtained by each stage of flash evaporation is respectively pressurized and then is used as a heat source of the heat-required end.
For example, the flash grade is 1 grade, and the gas phase stream after the first-stage flash is used as a heat source of the hot end after being pressurized.
For example, the flash evaporation grade is N grade, N is more than or equal to 2, except the Nth grade, each grade of flash evaporation pressurized is used as a heat source of a heat end needing to be heated; or the pressurized stream is mixed with the gas phase material flow to be pressurized in the next stage of flash evaporation, and the mixture is pressurized together; and pressurizing the gas-phase material flow obtained from the Nth stage and then taking the gas-phase material flow as a heat source of the heat end required. Illustratively, when N is 2, the gas phase material flow obtained by the first stage flash evaporation is pressurized and then mixed with the gas phase material flow obtained by the second stage flash evaporation, and the mixture is pressurized together and serves as a heat source of the hot end.
In the step (2), the barren solution obtained after flash evaporation is discharged outside and/or returned to an absorption tower for reuse.
For example, the flash grade is 1 grade, and the barren solution obtained by the first-stage flash is discharged outside and/or returned to an absorption tower for reuse.
For example, the flash grade is N grade, N is more than or equal to 2, and besides the Nth grade, the barren solution obtained by the flash evaporation of the previous stage is used as the feed of the flash evaporation of the next stage; and discharging the lean liquid obtained by the N-stage flash evaporation and/or returning the lean liquid to an absorption tower for reuse. Illustratively, when N is 2, the lean liquid obtained from the first-stage flash evaporation is used as the feed of the second-stage flash evaporation, and the lean liquid obtained from the second-stage flash evaporation is discharged outside and/or returned to the absorption tower for reuse.
In the step (2), performing primary flash evaporation on the high-temperature barren solution which is obtained at the bottom of the recovery tower and does not contain acrylonitrile basically, wherein a gas phase material flow obtained by the primary flash evaporation is used as a heat source of a heat end needing; and (3) discharging the lean solution obtained by the first-stage flash evaporation and/or returning the lean solution to an absorption tower for reuse.
In the step (2), performing primary flash evaporation and secondary flash evaporation on the high-temperature barren solution which is obtained at the bottom of the recovery tower and does not contain acrylonitrile basically, wherein gas-phase material flow obtained by the primary flash evaporation is mixed with gas-phase material flow obtained by the secondary flash evaporation after being pressurized, and the mixture is used as a heat source of a heat end to be heated after being pressurized together; and the barren solution obtained by the first-stage flash evaporation is used as the feeding material of the second-stage flash evaporation, and the barren solution obtained by the second-stage flash evaporation is discharged outside and/or returned to the absorption tower for reuse.
In the step (2), the gas phase material flow obtained after flash evaporation can be pressurized by a centrifugal compressor, a screw compressor, a reciprocating compressor, a Roots blower and a steam ejector.
Wherein the compression ratio of the compressor is 1.1-5.0.
The present invention also provides an apparatus for producing acrylonitrile, comprising: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash evaporation unit is connected with the bottom of the recovery tower; one end of the pressurizing unit is connected with a gas outlet of the flash evaporation unit, and the other end of the pressurizing unit is connected with the hot end to be heated;
the flash unit comprises at least one flash vessel and the pressure boosting unit comprises at least one pressure boosting device.
Preferably, the flash unit comprises at least two flash vessels.
Preferably, the pressurizing unit comprises at least two pressurizing means.
Preferably, the number of flash vessels is the same or different, preferably the same, as the number of pressure boosting devices.
According to the invention, the flash unit comprises at least two flash vessels, which are connected in series. Specifically, except the last stage of flash evaporator, a liquid outlet of the previous stage of flash evaporator is connected with a material inlet of the next stage of flash evaporator; the liquid outlet of the last stage flash evaporator is connected with an external pipeline.
According to the invention, the supercharging unit comprises at least two supercharging devices, except the last stage of supercharging device, a supercharging material flow outlet of the previous stage of supercharging device is connected with the heat end to be heated, or is connected with a material inlet of the next stage of supercharging device; and a pressurized material flow outlet of the last stage of pressurizing device is connected with the hot end.
According to the invention, the gas outlet of the first-stage flash evaporator is connected with the material inlet of the last-stage supercharging device, the gas outlet of the second-stage flash evaporator is connected with the material inlet of the penultimate supercharging device, and so on, and the gas outlet of the last-stage flash evaporator is connected with the material inlet of the first-stage supercharging device.
According to the present invention, the apparatus for producing acrylonitrile comprises: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash evaporation unit comprises a first-stage flash evaporator and a second-stage flash evaporator, and the pressurization unit comprises a first-stage compressor and a second-stage compressor;
the tower bottom of the recovery tower is connected with a material inlet of a first-stage flash evaporator, a liquid outlet of the first-stage flash evaporator is connected with a material inlet of a second-stage flash evaporator, and a liquid outlet of the second-stage flash evaporator is connected with an external pipeline;
the gas outlet of the first-stage flash evaporator is connected with the material inlet of the second-stage compressor, the gas outlet of the second-stage flash evaporator is connected with the material inlet of the first-stage compressor, the pressurized material flow outlet of the first-stage compressor is connected with the hot end required or connected with the material inlet of the second-stage compressor, and the pressurized material flow outlet of the second-stage compressor is connected with the hot end required.
According to the present invention, the apparatus for producing acrylonitrile comprises: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash evaporation unit comprises a primary flash evaporator, and the pressurization unit comprises a primary compressor;
the bottom of the recovery tower is connected with a material inlet of a primary flash evaporator, and a liquid outlet of the primary flash evaporator is connected with an external pipeline;
and a gas outlet of the primary flash evaporator is connected with a material inlet of the primary compressor, and a pressurized material flow outlet of the primary compressor is connected with a hot end.
According to the present invention, the apparatus for producing acrylonitrile comprises: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash unit comprises a primary flash vessel, and the pressure increasing unit comprises a steam ejector;
the bottom of the recovery tower is connected with a material inlet of a primary flash evaporator, and a liquid outlet of the primary flash evaporator is connected with an external pipeline;
and a gas outlet of the primary flash evaporator is connected with a material inlet of the steam ejector, and a material flow outlet of the steam ejector is connected with a hot end.
According to the invention, the hot end comprises at least one of a recovery tower, a waste water evaporator, a decyanation hydrogen chloride tower, a finished product tower and the like.
When the hot end required is the recovery tower, the pressurized flash steam can enter the bottom of the recovery tower to directly supply heat and/or enter a reboiler at the bottom of the recovery tower to indirectly supply heat as a heat source. That is, the recovery column is connected to a pressurizing unit, for example, the bottom of the recovery column is connected to the pressurizing unit, or the reboiler at the bottom of the recovery column is connected to the pressurizing unit.
The waste water evaporator is connected with the pressurizing unit and used for distilling and dehydrating the discharged barren solution to obtain condensate water and concentrated waste water, the condensate water is recycled, and the concentrated waste water is further treated. When the hot end to be heated is a waste water evaporator, the pressurized flash steam can enter the waste water evaporator for heat supply; namely, the waste water evaporator is connected with the pressurizing unit.
The hydrogen cyanide removing tower is connected with the top of the recovery tower and is used for separating the top of the recovery tower to obtain a gas phase material flow containing acrylonitrile so as to obtain hydrogen cyanide and an acrylonitrile crude product. When the hot end required is a hydrogen cyanide removal tower, pressurized flash steam enters a reboiler at the bottom of the hydrogen cyanide removal tower to be used as a heat source for indirect heat supply; namely, the reboiler at the bottom of the hydrogen cyanide removal tower is connected with the pressurizing unit.
Wherein, the finished product tower is connected with the hydrogen cyanide removal tower and is used for separating acrylonitrile crude products and preparing acrylonitrile products. When the hot end required is a finished product tower, the pressurized flash steam enters a reboiler at the bottom of the finished product tower to be used as a heat source for indirect heat supply; namely, the reboiler at the bottom of the finished product tower is connected with the pressurizing unit.
The invention has the beneficial effects that:
the invention provides a method and a device for producing acrylonitrile, wherein the method comprises the steps of carrying out flash evaporation on high-temperature barren liquor which is obtained at the bottom of a recovery tower and does not contain acrylonitrile basically, and pressurizing steam obtained by flash evaporation to be used as a heat source at least at one position of the recovery tower, a waste water evaporator, a decyanation hydrogen hydride tower, a finished product tower and the like.
Drawings
FIG. 1 is a process flow diagram of a two-stage flash pressurization process of example 1 of the present invention;
FIG. 2 is a process flow diagram of the pressurization of the flash injection pump of example 2 of the present invention;
FIG. 3 is a process flow diagram of a single stage flash pressure boost of example 3 of the present invention.
Reference numerals: A. a recovery tower, B, a reboiler at the bottom of the recovery tower, D, a steam ejector, E1, a first-stage compressor, E2, a second-stage compressor, V, a flash evaporator, V1, the first-stage flash evaporator, V2, the second-stage flash evaporator, 1, an acrylonitrile-containing rich liquid, 2, a reflux liquid, 3, a gas-phase stream at the top of the recovery tower, 4, a high-temperature barren liquid at the bottom of the recovery tower, 5, a barren liquid after the first-stage flash evaporation, 6, first-stage flash steam, 7, a barren liquid after the second-stage flash evaporation, 8, second-stage flash steam, 9, an inlet of the first-stage compressor, 10, an inlet of the second-stage compressor, 11, an outlet of the first-stage compressor, 13, pressurized flash steam, 14, a withdrawal, 15, a bottom liquid of the recovery tower, 16, additional steam, 17, flash steam going to a side-injection pump, 18, single-stage flash steam going to the compressor, 19, pressurized flash steam after injection, 20, and a vapor going to the side-compressor, And (3) spraying pump outlet steam, 21, and carrying out single-stage flash evaporation on the lean solution.
Detailed Description
The present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.
In the description of the present invention, it should be noted that the terms "first", "second", etc. are used for descriptive purposes only and do not indicate or imply relative importance.
Example 1
The recovery column a is used for the separation of acrylonitrile, hydrogen cyanide and acetonitrile as described in figure 1. The gas phase material flow 3 at the top of the recovery tower contains acrylonitrile, hydrogen cyanide and water, the condensed and layered organic phase (crude acrylonitrile) is sent to a hydrogen cyanide removal tower to remove the hydrogen cyanide, and the acrylonitrile is obtained by separation in a finished product tower. Reflux 2 is an aqueous phase at about 45 ℃, which may be a cooled lean liquor. And a reboiler B at the bottom of the recovery tower controls the temperature at the bottom of the recovery tower. 14, extracting a fraction containing acetonitrile, water and a small amount of hydrogen cyanide from a side line of a recovery tower, and removing the fraction to an acetonitrile tower to prepare crude acetonitrile. The bottom liquid 15 of the recovery tower is extracted and sent to a waste water evaporator for treatment. Feeding the high-temperature barren solution 4 at the bottom of the recovery tower into a first-stage flash evaporator V1 for flash evaporation to obtain first-stage flash evaporation steam 6 and first-stage flash evaporated barren solution 5, feeding the first-stage flash evaporated barren solution 5 into a first-stage flash evaporator V2 for flash evaporation to obtain second-stage flash evaporation steam 8 and second-stage flash evaporated barren solution 7; the second-stage flash steam 8 enters from a first-stage compressor inlet 9, is discharged from a first-stage compressor outlet 11 after being pressurized and is combined with the first-stage flash steam 6 to enter a second-stage compressor inlet 10, and the flash steam 13 discharged from the second-stage compressor outlet after being pressurized can be used as a heat source at least at one position of a recovery tower, a waste water evaporator, a decyanation hydrogen-sulfide tower, a finished product tower and the like.
Example 2
The recovery column a is used for the separation of acrylonitrile, hydrogen cyanide and acetonitrile as described in figure 2. The gas phase material flow 3 at the top of the recovery tower contains acrylonitrile, hydrogen cyanide and water, the condensed and layered organic phase (crude acrylonitrile) is sent to a hydrogen cyanide removal tower to remove the hydrogen cyanide, and the acrylonitrile is obtained by separation in a finished product tower. Reflux 2 is an aqueous phase at about 45 ℃, which may be a cooled lean liquor. And a reboiler B at the bottom of the recovery tower controls the temperature at the bottom of the recovery tower. 14, extracting a fraction containing acetonitrile, water and a small amount of hydrogen cyanide from a side line of a recovery tower, and removing the fraction to an acetonitrile tower to prepare crude acetonitrile. The bottom liquid 15 of the recovery tower is extracted and sent to a waste water evaporator for treatment. The high-temperature barren liquor 4 at the bottom of the recovery tower enters a flash evaporator V for flash evaporation, additional steam 16 passes through an ejector D, flash steam 17 removed from the ejector is sucked by the ejector, and steam 20 at the outlet of the ejector can be used as a heat source of at least one position of the recovery tower, a waste water evaporator, a decyanation hydrogen-hydride tower, a finished product tower and the like.
Example 3
The recovery column a is used for the separation of acrylonitrile, hydrogen cyanide and acetonitrile as described in figure 3. The gas phase material flow 3 at the top of the recovery tower contains acrylonitrile, hydrogen cyanide and water, the condensed and layered organic phase (crude acrylonitrile) is sent to a hydrogen cyanide removal tower to remove the hydrogen cyanide, and the acrylonitrile is obtained by separation in a finished product tower. Reflux 2 is an aqueous phase at about 45 ℃, which may be a cooled lean liquor. And a reboiler B at the bottom of the recovery tower controls the temperature at the bottom of the recovery tower. 14, extracting a fraction containing acetonitrile, water and a small amount of hydrogen cyanide from a side line of a recovery tower, and removing the fraction to an acetonitrile tower to prepare crude acetonitrile. The bottom liquid 15 of the recovery tower is extracted and sent to a waste water evaporator for treatment. The high-temperature barren liquor 4 at the bottom of the recovery tower enters a flash evaporator V for flash evaporation to obtain flash evaporation steam 18 from a compressor and barren liquor 21 after flash evaporation, and the flash evaporation steam 18 from the compressor is compressed by a compressor E to obtain pressurized flash evaporation steam 13 which can be used as a heat source at least at one position of the recovery tower, a waste water evaporator, a decyanation hydrogen sulfide tower, a finished product tower and the like.
Example 4
Take a recovery column of an acrylonitrile plant of 4 ten thousand tons/year as an example.
The process flow shown in fig. 1 was used.
102700kg/h of pregnant solution from an absorption tower, the temperature after heat exchange is 66 ℃, wherein the pregnant solution contains 5.3 wt% of acrylonitrile, 0.2 wt% of acetonitrile, 0.6 wt% of hydrogen cyanide and 0.4 wt% of acrolein, the pregnant solution enters from the middle upper part of a recovery tower, and a reboiler controls the temperature of the recovery tower by taking 0.4MPa steam as a heat source. The gas phase at the top of the recovery tower has the temperature of 69 ℃, the pressure of 110kPa, the flow rate of 7340kg/h, and the gas phase contains 80 wt% of acrylonitrile, 8.3 wt% of hydrogen cyanide and 11.7 wt% of water, and is used for separating the hydrogen cyanide and the acrylonitrile in the next step. The reflux at the top of the column was 47000kg/h of lean solution at 48 ℃. The side stream of the recovery tower is extracted to be 110 ℃, and the gas phase fraction containing 8.5 wt% of acetonitrile, 0.3 wt% of hydrogen cyanide and 91.2 wt% of water is removed to the acetonitrile tower. The waste water extracted from the tower bottom liquid at 115 ℃, 300kPa, 8600kg/h is treated by a waste water evaporator. 134300kg/h of high-temperature barren solution at the tower bottom at 115 ℃ enters a first-stage flash evaporator for flash evaporation to obtain 120kPa, 2780kg/h of flash evaporation steam at 105 ℃, the high-temperature barren solution after primary flash evaporation enters a second-stage flash evaporator for secondary flash evaporation to obtain 85kPa, 2630kg/h of secondary flash evaporation steam at 95 ℃, the secondary flash evaporation steam enters an inlet of the first-stage compressor for compression, 120kPa compressed gas is discharged from an outlet of the first-stage compressor and mixed with the primary flash evaporation steam and then enters an inlet of the second-stage compressor, pressurized flash evaporation steam is discharged from an outlet of the second-stage compressor at 5410kg/h, the pressure is 310kPa, the temperature is 255 ℃, and the high-temperature barren solution can be used as a heat source at least one position of a recovery tower, a waste water evaporator, a decyanation hydrogen tower, a finished product tower and the like.
The steam is saved by 5410kg/h, and the steam cost is saved by 811 yuan/h; the power of the compressor is increased by 475kW, and the electric charge is increased by 308 yuan/h; the cost is saved: 811-308 equals 503 yuan/h.
Example 5
The recovery column feed and column pressure and temperature were the same as in example 4. The difference is that the flow of the figure 2 is used as the treatment mode of the high-temperature barren solution, 4000kg/h of additional steam with the pressure of 500kPa is injected into an injection pump D, 134300kg/h of the high-temperature barren solution enters a flash evaporator V, the flash steam is brought into an injector by the vacuum generated by a steam injection pump, the steam at the outlet of the steam injector is 6100kg/h of 300kPa, and the high-temperature barren solution can be used as a heat source at least at one position of a recovery tower, a waste water evaporator, a decyanation hydrogen tower, a finished product tower and the like.
Saving 2100kg/h (6100kg/h-4000kg/h) of steam, saving steam cost: 315 yuan/h.
Example 6
The recovery column feed and column pressure and temperature were the same as in example 4. The difference is that the flow of the figure 3 is used as the treatment mode of the high-temperature barren solution, 134300kg/h barren solution enters a flash evaporator V, the obtained 0.085MPa flash steam with the temperature of 95 ℃ is 5420kg/h, the flash steam enters a compressor to be pressurized to 310kPa, and the pressurized steam can be used as a heat source at least at one position of a recovery tower, a waste water evaporator, a decyanation hydrogen tower, a finished product tower and the like.
The steam is saved by 5420kg/h, and the steam cost is saved by 813 yuan/h; the power of the compressor is increased by 550kW, and the electric charge is increased by 357 Yuan/h; the cost is saved: 813 ═ 357 is 456/h.
The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A process for the production of acrylonitrile, wherein the process comprises the steps of:
(1) carrying out steam stripping separation on the rich liquid containing the acrylonitrile in a recovery tower, obtaining a gas phase material flow containing the acrylonitrile at the top of the recovery tower, and obtaining a high-temperature barren liquid basically not containing the acrylonitrile at the bottom of the recovery tower;
(2) and (3) carrying out flash evaporation on the high-temperature barren liquor which is obtained at the bottom of the recovery tower and is basically free of acrylonitrile, and taking steam obtained by flash evaporation as a heat source of a hot end.
2. The production method according to claim 1, wherein the hot end-in-need comprises at least one of a recovery column, a waste water evaporator, a decyanation hydrogen column, and a finishing column.
3. The production process according to claim 1 or 2, wherein in the step (1), the rich liquid containing acrylonitrile is obtained by:
cooling the gas phase material flow of the reaction product obtained by propylene and/or propane ammoxidation, sending the cooled gas phase material flow into a quenching and ammonia removal section, contacting the gas phase material flow of the reaction product subjected to quenching and ammonia removal treatment with water in an absorption tower, and obtaining the pregnant solution containing acrylonitrile at the bottom of the absorption tower.
4. The production process according to any one of claims 1 to 3, wherein in the step (1), the content of acrylonitrile in the rich liquid containing acrylonitrile is 2 to 10% by weight.
Preferably, in the step (1), the temperature of the gas phase material flow containing the acrylonitrile obtained at the top of the recovery tower is 50-90 ℃, and the pressure is 110-120 kPa; the temperature of the high-temperature barren solution which is basically free of acrylonitrile and is obtained at the bottom of the recovery tower is 90-130 ℃, and the pressure is 110-350 kPa.
5. The production process according to any one of claims 1 to 4, wherein in step (2), the flashing is carried out at least at one pressure level, preferably the flashing is carried out at least at two pressure levels.
Preferably, in step (2), the vapor stream obtained from each stage of flashing is pressurized.
Preferably, in the step (2), the gas phase stream obtained by each stage of flash evaporation is respectively pressurized and then used as a heat source of the hot end.
Preferably, the flash evaporation grade is 1 grade, and the gas phase material flow after the first-stage flash evaporation is used as a heat source of the hot end.
Preferably, the flash evaporation grade is N grade, N is more than or equal to 2, except the Nth grade, each grade of flash evaporation pressurized is used as a heat source of the heat end needing; or the pressurized stream is mixed with the gas phase material flow to be pressurized in the next stage of flash evaporation, and the mixture is pressurized together; and pressurizing the gas-phase material flow obtained from the Nth stage and then taking the gas-phase material flow as a heat source of the heat end required.
Preferably, N is 2, the gas phase material flow obtained by the first stage flash evaporation is pressurized, then is mixed with the gas phase material flow obtained by the second stage flash evaporation, and is pressurized together to be used as a heat source of the hot end.
Preferably, in the step (2), the lean solution obtained after flashing is discharged outside and/or returned to the absorption tower for reuse.
Preferably, the flash grade is 1 grade, and the barren solution obtained by the first-stage flash is discharged outside and/or returned to the absorption tower for reuse.
Preferably, the flash grade is N grade, N is more than or equal to 2, and besides the Nth grade, barren solution obtained by the flash evaporation of the previous grade is used as the feeding material of the flash evaporation of the next grade; and discharging the lean liquid obtained by the N-stage flash evaporation and/or returning the lean liquid to an absorption tower for reuse.
Preferably, N is 2, the barren solution obtained from the first stage flash evaporation is used as the feed of the second stage flash evaporation, and the barren solution obtained from the second stage flash evaporation is discharged outside and/or returned to the absorption tower for reuse.
6. The production method according to any one of claims 1 to 5, wherein in the step (2), the gas phase stream obtained after the flash evaporation is pressurized by a centrifugal compressor, a screw compressor, a reciprocating compressor, a Roots blower and a steam ejector.
7. An apparatus for producing acrylonitrile, the apparatus comprising: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash evaporation unit is connected with the bottom of the recovery tower; one end of the pressurizing unit is connected with a gas outlet of the flash evaporation unit, and the other end of the pressurizing unit is connected with the hot end to be heated;
the flash unit comprises at least one flash vessel and the pressure boosting unit comprises at least one pressure boosting device.
8. The production plant of claim 7 wherein the flash unit comprises at least two flash vessels connected in series.
Preferably, the pressurizing unit comprises at least two pressurizing means.
Preferably, the flash unit comprises at least two flash vessels, the two or more flash vessels being connected in series.
Preferably, except the last stage of flash evaporator, the liquid outlet of the previous stage of flash evaporator is connected with the material inlet of the next stage of flash evaporator; the liquid outlet of the last stage flash evaporator is connected with an external pipeline.
Preferably, the pressurizing unit comprises at least two pressurizing devices, except the last stage of pressurizing device, a pressurized material flow outlet of the previous stage of pressurizing device is connected with the hot end to be heated, or is connected with a material inlet of the next stage of pressurizing device; and a pressurized material flow outlet of the last stage of pressurizing device is connected with the hot end.
Preferably, the gas outlet of the first-stage flash evaporator is connected with the material inlet of the last-stage supercharging device, the gas outlet of the second-stage flash evaporator is connected with the material inlet of the penultimate supercharging device, and so on, and the gas outlet of the last-stage flash evaporator is connected with the material inlet of the first-stage supercharging device.
9. The production apparatus according to claim 7, wherein the production apparatus for acrylonitrile comprises: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash evaporation unit comprises a first-stage flash evaporator and a second-stage flash evaporator, and the pressurization unit comprises a first-stage compressor and a second-stage compressor;
the tower bottom of the recovery tower is connected with a material inlet of a first-stage flash evaporator, a liquid outlet of the first-stage flash evaporator is connected with a material inlet of a second-stage flash evaporator, and a liquid outlet of the second-stage flash evaporator is connected with an external pipeline;
the gas outlet of the first-stage flash evaporator is connected with the material inlet of the second-stage compressor, the gas outlet of the second-stage flash evaporator is connected with the material inlet of the first-stage compressor, the pressurized material flow outlet of the first-stage compressor is connected with the hot end required or connected with the material inlet of the second-stage compressor, and the pressurized material flow outlet of the second-stage compressor is connected with the hot end required;
alternatively, the first and second electrodes may be,
the apparatus for producing acrylonitrile comprises: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash evaporation unit comprises a primary flash evaporator, and the pressurization unit comprises a primary compressor;
the bottom of the recovery tower is connected with a material inlet of a primary flash evaporator, and a liquid outlet of the primary flash evaporator is connected with an external pipeline;
a gas outlet of the primary flash evaporator is connected with a material inlet of a primary compressor, and a pressurized material flow outlet of the primary compressor is connected with a hot end to be heated;
in the further alternative,
the apparatus for producing acrylonitrile comprises: the system comprises a recovery tower, a flash evaporation unit and a pressurization unit; the flash unit comprises a primary flash vessel, and the pressure increasing unit comprises a steam ejector;
the bottom of the recovery tower is connected with a material inlet of a primary flash evaporator, and a liquid outlet of the primary flash evaporator is connected with an external pipeline;
and a gas outlet of the primary flash evaporator is connected with a material inlet of the steam ejector, and a material flow outlet of the steam ejector is connected with a hot end.
10. The production device of any one of claims 7 to 9, wherein the hot end comprises at least one of a recovery column, a waste water evaporator, a decyanation hydrogen column, and a finishing column.
Preferably, when the hot end is a recovery tower, the recovery tower is connected with a pressurizing unit, for example, the bottom of the recovery tower is connected with the pressurizing unit, or a reboiler at the bottom of the recovery tower is connected with the pressurizing unit.
Preferably, when the hot end needing heat is a waste water evaporator, the pressurized flash steam can enter the waste water evaporator for supplying heat; namely, the waste water evaporator is connected with the pressurizing unit.
Preferably, the hydrogen cyanide removal tower is connected with the top of the recovery tower, and when the hot end required is the hydrogen cyanide removal tower, pressurized flash steam enters a reboiler at the bottom of the hydrogen cyanide removal tower and is used as a heat source for indirectly supplying heat; namely, the reboiler at the bottom of the hydrogen cyanide removal tower is connected with the pressurizing unit.
Preferably, the finished product tower is connected with the hydrogen cyanide removal tower, and when the hot end required is the finished product tower, the pressurized flash steam enters a reboiler at the bottom of the finished product tower and is used as a heat source for indirect heat supply; namely, the reboiler at the bottom of the finished product tower is connected with the pressurizing unit.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001121138A (en) * | 1999-10-28 | 2001-05-08 | Asahi Kasei Corp | Method for treating waste water |
| CN107473294A (en) * | 2017-08-31 | 2017-12-15 | 上海晟兰石化工程技术有限公司 | A kind of handling process and processing system of acrylonitrile recovery tower tower bottoms |
| CN108136321A (en) * | 2015-09-08 | 2018-06-08 | 卡普索-Eop股份公司 | For CO2The method and apparatus of trapping |
| CN113559540A (en) * | 2020-04-29 | 2021-10-29 | 北京诺维新材科技有限公司 | Stripping method and stripping device for ethylene oxide |
| CN113620909A (en) * | 2020-05-07 | 2021-11-09 | 北京诺维新材科技有限公司 | Saponification method and saponification device |
-
2020
- 2020-05-09 CN CN202010388160.3A patent/CN113620839A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001121138A (en) * | 1999-10-28 | 2001-05-08 | Asahi Kasei Corp | Method for treating waste water |
| CN108136321A (en) * | 2015-09-08 | 2018-06-08 | 卡普索-Eop股份公司 | For CO2The method and apparatus of trapping |
| CN107473294A (en) * | 2017-08-31 | 2017-12-15 | 上海晟兰石化工程技术有限公司 | A kind of handling process and processing system of acrylonitrile recovery tower tower bottoms |
| CN113559540A (en) * | 2020-04-29 | 2021-10-29 | 北京诺维新材科技有限公司 | Stripping method and stripping device for ethylene oxide |
| CN113620909A (en) * | 2020-05-07 | 2021-11-09 | 北京诺维新材科技有限公司 | Saponification method and saponification device |
Non-Patent Citations (1)
| Title |
|---|
| 李凯: "机械式蒸汽再压缩技术处理丙烯腈精制废水的研究", 《中国优秀硕士学位论文全文数据库 工程科技I辑》, no. 4, pages 2 - 1 * |
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