CN111320520B - Extractive distillation tower for butadiene separation and separation method - Google Patents
Extractive distillation tower for butadiene separation and separation method Download PDFInfo
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- CN111320520B CN111320520B CN201811533074.6A CN201811533074A CN111320520B CN 111320520 B CN111320520 B CN 111320520B CN 201811533074 A CN201811533074 A CN 201811533074A CN 111320520 B CN111320520 B CN 111320520B
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- polymerization inhibitor
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- KAKZBPTYRLMSJV-UHFFFAOYSA-N Butadiene Chemical compound C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 title claims abstract description 88
- 238000000926 separation method Methods 0.000 title claims abstract description 19
- 238000000895 extractive distillation Methods 0.000 title claims description 16
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 49
- 239000003112 inhibitor Substances 0.000 claims abstract description 43
- 238000000605 extraction Methods 0.000 claims abstract description 34
- 239000000725 suspension Substances 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims abstract description 13
- 238000011068 loading method Methods 0.000 claims abstract description 6
- 238000010992 reflux Methods 0.000 claims description 30
- 239000000463 material Substances 0.000 claims description 15
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 claims description 12
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 9
- 239000002994 raw material Substances 0.000 claims description 9
- 239000002904 solvent Substances 0.000 claims description 8
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 claims description 7
- 150000003254 radicals Chemical class 0.000 claims description 6
- AVXURJPOCDRRFD-UHFFFAOYSA-N Hydroxylamine Chemical class ON AVXURJPOCDRRFD-UHFFFAOYSA-N 0.000 claims description 5
- 150000002989 phenols Chemical class 0.000 claims description 5
- 150000001412 amines Chemical class 0.000 claims description 4
- KDKYADYSIPSCCQ-UHFFFAOYSA-N but-1-yne Chemical group CCC#C KDKYADYSIPSCCQ-UHFFFAOYSA-N 0.000 claims description 4
- MWWATHDPGQKSAR-UHFFFAOYSA-N propyne Chemical group CC#C MWWATHDPGQKSAR-UHFFFAOYSA-N 0.000 claims description 4
- 229910001220 stainless steel Inorganic materials 0.000 claims description 4
- 239000010935 stainless steel Substances 0.000 claims description 4
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 3
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- KOYGZROXUOTUEE-UHFFFAOYSA-N butane;but-1-ene Chemical compound CCCC.CCC=C KOYGZROXUOTUEE-UHFFFAOYSA-N 0.000 claims description 2
- WFYPICNXBKQZGB-UHFFFAOYSA-N butenyne Chemical group C=CC#C WFYPICNXBKQZGB-UHFFFAOYSA-N 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims description 2
- AQSJGOWTSHOLKH-UHFFFAOYSA-N phosphite(3-) Chemical class [O-]P([O-])[O-] AQSJGOWTSHOLKH-UHFFFAOYSA-N 0.000 claims description 2
- 150000002443 hydroxylamines Chemical class 0.000 claims 1
- 229920000642 polymer Polymers 0.000 abstract description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract description 3
- 230000008859 change Effects 0.000 abstract description 2
- 230000006872 improvement Effects 0.000 abstract description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 229910052799 carbon Inorganic materials 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- -1 piperidine oxygen free radical Chemical class 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 239000000126 substance Substances 0.000 description 4
- RKMGAJGJIURJSJ-UHFFFAOYSA-N 2,2,6,6-Tetramethylpiperidine Substances CC1(C)CCCC(C)(C)N1 RKMGAJGJIURJSJ-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 150000001993 dienes Chemical class 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000002401 inhibitory effect Effects 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- WERYXYBDKMZEQL-UHFFFAOYSA-N butane-1,4-diol Chemical compound OCCCCO WERYXYBDKMZEQL-UHFFFAOYSA-N 0.000 description 2
- KBPLFHHGFOOTCA-UHFFFAOYSA-N caprylic alcohol Natural products CCCCCCCCO KBPLFHHGFOOTCA-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000008676 import Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 150000002978 peroxides Chemical class 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- OJMIONKXNSYLSR-UHFFFAOYSA-N phosphorous acid Chemical compound OP(O)O OJMIONKXNSYLSR-UHFFFAOYSA-N 0.000 description 2
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 description 2
- RRKODOZNUZCUBN-CCAGOZQPSA-N (1z,3z)-cycloocta-1,3-diene Chemical compound C1CC\C=C/C=C\C1 RRKODOZNUZCUBN-CCAGOZQPSA-N 0.000 description 1
- UFBJCMHMOXMLKC-UHFFFAOYSA-N 2,4-dinitrophenol Chemical compound OC1=CC=C([N+]([O-])=O)C=C1[N+]([O-])=O UFBJCMHMOXMLKC-UHFFFAOYSA-N 0.000 description 1
- HOYRZHJJAHRMLL-UHFFFAOYSA-N 2,6-dinitro-p-cresol Chemical compound CC1=CC([N+]([O-])=O)=C(O)C([N+]([O-])=O)=C1 HOYRZHJJAHRMLL-UHFFFAOYSA-N 0.000 description 1
- IQUPABOKLQSFBK-UHFFFAOYSA-N 2-nitrophenol Chemical compound OC1=CC=CC=C1[N+]([O-])=O IQUPABOKLQSFBK-UHFFFAOYSA-N 0.000 description 1
- JIGUICYYOYEXFS-UHFFFAOYSA-N 3-tert-butylbenzene-1,2-diol Chemical compound CC(C)(C)C1=CC=CC(O)=C1O JIGUICYYOYEXFS-UHFFFAOYSA-N 0.000 description 1
- UWDMKTDPDJCJOP-UHFFFAOYSA-N 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-ium-4-carboxylate Chemical compound CC1(C)CC(O)(C(O)=O)CC(C)(C)N1 UWDMKTDPDJCJOP-UHFFFAOYSA-N 0.000 description 1
- 229920001174 Diethylhydroxylamine Polymers 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 239000005062 Polybutadiene Substances 0.000 description 1
- AZFNGPAYDKGCRB-XCPIVNJJSA-M [(1s,2s)-2-amino-1,2-diphenylethyl]-(4-methylphenyl)sulfonylazanide;chlororuthenium(1+);1-methyl-4-propan-2-ylbenzene Chemical compound [Ru+]Cl.CC(C)C1=CC=C(C)C=C1.C1=CC(C)=CC=C1S(=O)(=O)[N-][C@@H](C=1C=CC=CC=1)[C@@H](N)C1=CC=CC=C1 AZFNGPAYDKGCRB-XCPIVNJJSA-M 0.000 description 1
- PBCJIPOGFJYBJE-UHFFFAOYSA-N acetonitrile;hydrate Chemical compound O.CC#N PBCJIPOGFJYBJE-UHFFFAOYSA-N 0.000 description 1
- BTGRAWJCKBQKAO-UHFFFAOYSA-N adiponitrile Chemical compound N#CCCCCC#N BTGRAWJCKBQKAO-UHFFFAOYSA-N 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- KVNRLNFWIYMESJ-UHFFFAOYSA-N butyronitrile Chemical compound CCCC#N KVNRLNFWIYMESJ-UHFFFAOYSA-N 0.000 description 1
- 150000001728 carbonyl compounds Chemical class 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 238000004939 coking Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- ZOLLIQAKMYWTBR-RYMQXAEESA-N cyclododecatriene Chemical compound C/1C\C=C\CC\C=C/CC\C=C\1 ZOLLIQAKMYWTBR-RYMQXAEESA-N 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- FVCOIAYSJZGECG-UHFFFAOYSA-N diethylhydroxylamine Chemical compound CCN(O)CC FVCOIAYSJZGECG-UHFFFAOYSA-N 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 238000005194 fractionation Methods 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- ACCCMOQWYVYDOT-UHFFFAOYSA-N hexane-1,1-diol Chemical compound CCCCCC(O)O ACCCMOQWYVYDOT-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- VMESOKCXSYNAKD-UHFFFAOYSA-N n,n-dimethylhydroxylamine Chemical compound CN(C)O VMESOKCXSYNAKD-UHFFFAOYSA-N 0.000 description 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N n-Octanol Natural products CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- RRUADNNEIGVWSQ-UHFFFAOYSA-N n-ethyl-n-methylhydroxylamine Chemical compound CCN(C)O RRUADNNEIGVWSQ-UHFFFAOYSA-N 0.000 description 1
- 229920001084 poly(chloroprene) Polymers 0.000 description 1
- 229920002857 polybutadiene Polymers 0.000 description 1
- 235000010289 potassium nitrite Nutrition 0.000 description 1
- 239000004304 potassium nitrite Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 235000010288 sodium nitrite Nutrition 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- HXJUTPCZVOIRIF-UHFFFAOYSA-N sulfolane Chemical compound O=S1(=O)CCCC1 HXJUTPCZVOIRIF-UHFFFAOYSA-N 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 229920003051 synthetic elastomer Polymers 0.000 description 1
- 239000005061 synthetic rubber Substances 0.000 description 1
Classifications
-
- 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
-
- 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
- B01D3/34—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping with one or more auxiliary substances
- B01D3/40—Extractive distillation
-
- 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
- C07C7/05—Purification; Separation; Use of additives by distillation with the aid of auxiliary compounds
- C07C7/08—Purification; Separation; Use of additives by distillation with the aid of auxiliary compounds by extractive distillation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Abstract
The invention discloses an extraction rectifying tower and a separating method for butadiene separation. The invention overcomes the defect of unstable and unbalanced concentration of the polymerization inhibitor in the system when the polymerization inhibitor is added into the system intermittently or along with the extractant by changing the adding mode of the polymerization inhibitor, so as to ensure the stability and balance of the concentration of the polymerization inhibitor in the system. The suspension covers for loading the polymerization inhibitor are arranged in the extraction rectifying tower and on the top return pipeline, so that the polymerization inhibitor is released into the system according to a certain rate after being completely dissolved in the extractant, the concentration of the polymerization inhibitor at each position of the rectifying tower is ensured to be basically consistent, the change of the polymerization inhibitor with time is small, the formation of polymers and the blockage of equipment are greatly reduced, and the long-period stable operation of the device and the improvement of the production efficiency are facilitated.
Description
Technical Field
The invention belongs to the field of chemical industry, relates to separation equipment and a separation method, and particularly relates to an extraction rectifying tower and a separation method for effectively inhibiting butadiene polymerization in the process of separating butadiene from petroleum carbon four fractions through extraction rectification.
Background
Butadiene is mainly used for synthesizing butadiene benzene, polybutadiene, butyronitrile, chloroprene rubber, ABS, BS, SBS, MBS and other resins, and is also a fine chemical raw material with wide application range, and is used for producing sulfolane, 1, 4-butanediol, n-octanol, hexanediol, adiponitrile, cyclooctadiene, 1,5, 9-cyclododecatriene and other organic chemical products. In the synthetic rubber produced at present, more than 80% of butadiene is used as a main raw material. Butadiene is mainly derived from ethylene cracking carbon four and mainly adopts an extractive distillation method. Depending on the solvent used, dimethylformamide, acetonitrile, methylpyrrolidone, and the like can be classified. However, regardless of the He Chongding diene extraction process, trace amounts of oxygen, water and other impurities are present in the extraction device, and these factors often promote butadiene formation into end polymers, peroxides and the like, and the carbonyl compounds and carbon five dienes present in the feedstock produce gum-like polymers. In addition, solvents and added chemicals also produce gums during the manufacturing process. Therefore, in the extraction column, fractionation column, reboiler, etc., scale is often formed by polymerization of butadiene, etc., and equipment is blocked. The production of the polymer not only consumes butadiene and affects the yield, but also seriously affects the long-period stable operation of the butadiene extraction device and even needs to be stopped and overhauled due to the blockage of equipment such as a tower, a tank, a heat exchanger, a pipeline and the like. Therefore, the generation of coking and scaling substances in the butadiene extraction device is inhibited, and the method is very important for long-period stable operation of the device, prolonging of the service life of equipment, energy saving and consumption reduction.
The injection of polymerization inhibitor into butadiene extraction device is an effective means for inhibiting coke formation in the device, in the prior art and production system, the widely used polymerization inhibitor system in butadiene separation process is mainly nitrite, and polymerization inhibitor components such as piperidine oxygen free radical, phenols, hydroxylamine, phosphite, nitro or amine are added in an auxiliary way. They can combine with oxygen in the system and the free radical of the polymer to deactivate it, thus achieving the purpose of inhibiting the production of peroxide and elastic polymer. The polymerization inhibitor such as nitrite is added intermittently or along with the extraction solvent in the two-stage extraction and rectification process, the intermittent mode causes the concentration of the polymerization inhibitor in the system to be too high when the polymerization inhibitor is just added, and then the polymerization inhibitor is attenuated gradually, so that excessive polymerization inhibitor is often required to be added for ensuring the later polymerization inhibition effect; and when the extraction solvent is added, the polymerization inhibitor is unevenly distributed in the tower, the local polymer deposition blocks the equipment pipeline, the operation period and the production efficiency are seriously affected, and potential safety hazards are caused.
Chinese patent CN200680002630.6 discloses a polymerization inhibitor for 1, 3-butadiene extractive distillation system, wherein a composite polymerization inhibitor is introduced from the top of the distillation column, and the polymerization inhibitor is prepared by dissolving hydroxylamine and phenols in a solvent, and can effectively prevent polymerization in gas-liquid two phases. Chinese patent CN200910088178.5 discloses a polymerization inhibitor for 1, 3-butadiene extraction device, which comprises phenols, amines, phosphites, and the polymerization inhibitor is injected into the feed line of extraction solvent and the return line of the second extraction tower by electromagnetic metering pump, and the injection concentration is 1-2000 ppm, preferably 1-1000 ppm, based on the amount of four feeds of cracked carbon.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides an extraction rectifying tower and a separation method for separating butadiene from petroleum carbon four fractions, and a suspension cover for loading polymerization inhibitor is added at a plurality of positions in the extraction rectifying tower, so that quantitative nitrite and other components of the polymerization inhibitor are fully dissolved and then released into a system according to a certain rate, and the stability and balance of the concentration of the polymerization inhibitor in the system are ensured.
The following is a specific technical scheme of the invention:
the utility model provides an extraction rectifying column for butadiene separation, including the rectifying column body, the middle part of rectifying column body is equipped with the feed inlet, the position that is close to the top of the tower on the rectifying column body is equipped with the solvent inlet, the tower bottom of rectifying column body is equipped with the tower bottom pipeline, be connected with cauldron liquid pump and reboiler on the tower bottom pipeline, the top of rectifying column body is equipped with the reflux liquid import, the top of rectifying column body passes through the pipe connection reflux pump, the reflux pump liquid outlet is connected with reflux liquid import and product jar respectively, be equipped with a plurality of suspension covers that are used for loading the polymerization inhibitor in the rectifying column body and on the top reflux pipeline, the suspension cover comprises 10 ~ 80 mesh screen cloth cladding stainless steel support.
Preferably, in the extractive distillation column, the suspension cover is uniformly arranged at the top of the column, below the feed inlet, on the column body and on the column bottom.
The invention also provides a method for separating butadiene by using the separation equipment, which comprises the following steps:
1) And (3) feeding the raw material rich in butadiene into a first extraction rectifying tower to obtain a tower kettle material rich in butadiene, and separating butane butene from the tower top. Wherein, the weight ratio of the raw materials to the extractant is 1: (4-20), the operating pressure is normal pressure, the temperature of the tower bottom of the rectifying tower is 70-150 ℃, and the reflux ratio is 0.8-20;
2) And (2) feeding the tower kettle material obtained in the step (1) into a first stripping tower, and separating butadiene from an extracting agent to obtain a tower top material containing butadiene, ethyl acetylene, vinyl acetylene and methyl acetylene. Wherein the operating pressure is normal pressure, the temperature of the bottom of the stripping tower is 60-200 ℃, and the reflux ratio is 1-6;
3) And (3) feeding the tower top material obtained in the step (2) into a second extraction rectifying tower to obtain a tower top material rich in butadiene. Wherein the feeding weight ratio of butadiene to extractant is 1: (4-20), the operating pressure is normal pressure, the temperature of the tower bottom of the rectifying tower is 60-150 ℃, and the reflux ratio is 1-10;
4) And 3) feeding the tower top material obtained in the step 3) into a second stripping tower, removing heavy components in the material at the tower bottom, removing trace propyne at the tower top, and distilling the polymerization-grade pure butadiene product from the side line of the stripping tower. Wherein the operating pressure is normal pressure, the reflux ratio is 1-6, and the temperature of the bottom of the stripping tower is 40-100 ℃;
in the first extraction rectifying tower and the second extraction rectifying tower in the step 1) and the step 3), the polymerization inhibitor loaded in the suspension cover is mainly nitrite, and one or a combination of more of nitroxide free radicals, phenols, hydroxylamine, phosphite, nitro and amine is added in an auxiliary way. The nitrite may be sodium nitrite or potassium nitrite. An auxiliary component is used for preparing the auxiliary component, can be 4-hydroxy-2, 6-tetramethyl piperidine oxygen free radical, 2, 6-tetramethyl piperidine oxygen free radical, 4-oxo-2, 6-tetramethyl piperidine oxygen free radical, 2, 4-dinitrophenol, 2, 6-dinitro-p-cresol tert-butyl catechol, o-nitrophenol, diethyl hydroxylamine, dimethyl hydroxylamine, methyl ethyl hydroxylamine, dipiperidine nitroxide hydrogen phosphite, tripiperidine nitroxide phosphite, phosphorous triesters and phosphorous acid diesters.
The extractant in the step 1) and the step 3) is any one of dimethylformamide, N-methylpyrrolidone, acetonitrile or acetonitrile water solution with the water content of 5-15 wt%.
The weight ratio of the raw materials to the extractant in the step 1) is preferably 1: (7-9), the temperature of the tower bottom of the rectifying tower is preferably 70-140 ℃, and the reflux ratio is preferably 0.8-4.
The temperature of the bottom of the stripping tower in the step 2) is preferably 60-150 ℃, and the reflux ratio is preferably 1-3.
The feed weight ratio of butadiene to extractant described in step 3) above is preferably 1: (4-8), the temperature of the tower bottom of the rectifying tower is preferably 70-140 ℃, and the reflux ratio is preferably 1-3.
The reflux ratio in the step 4) is preferably 1-3, and the temperature of the stripping tower kettle is preferably 40-65 ℃.
The essence of the invention is that the adding mode of the polymerization inhibitor is changed by arranging a plurality of suspension covers for loading the polymerization inhibitor in the extraction rectifying tower. Butadiene is a diene with high activity, and under the condition of insufficient polymerization inhibitor quantity, cross-linking polymerization is easy to occur, and the boiling point is low, polymerization burst can occur even in a reflux tank and a reflux pipeline, so that suspension covers are uniformly and densely arranged at all parts of a tower and in a reflux loop, and the polymerization inhibitor can be uniformly distributed in the tower. In the embodiment provided by the invention, the polymerization inhibitor is placed in the suspension cover, and the suspension cover is uniformly placed on each position in the tower and the top return pipeline, wherein each position in the tower comprises the tower top, the lower part of the feed inlet, the tower bottom and the tower body. The inventor makes the extractant fully dissolve the polymerization inhibitor in the butadiene separation process through the structure of the suspension cover and the design of distribution, and the polymerization inhibitor is released into the system according to a certain rate. The suspension covers are distributed and fixedly arranged in the tower body at intervals of 8-10 meters
Compared with the prior art, the invention has the beneficial effects that:
1. the concentration of the polymerization inhibitor at each position of the extraction rectifying tower is basically consistent, the change of the polymerization inhibitor along with time is not great, and the defect of unstable and unbalanced concentration of the polymerization inhibitor in the system when the polymerization inhibitor is added into the system in a batch or extractant-following mode is overcome;
2. the polymerization inhibitor containing nitrite is completely dissolved in the extractant and then slowly released into the system, excessive salt is not present in the system, and the polymerization center is not formed by crystallization in the extractive distillation tower, so that the formation of polymer and the blockage of equipment are greatly reduced, and the long-period stable operation of the device and the improvement of production efficiency are facilitated.
Drawings
FIG. 1 is a process flow diagram of examples 1 to 10. FIG. 2 is a schematic view of an extractive distillation column in the invention, wherein a plurality of suspension covers for loading polymerization inhibitor are arranged in the extractive distillation column, and the suspension covers are formed by stainless steel brackets coated by screens with the number of 10-80 meshes.
Symbol description:
in FIG. 1, 1-first extractive distillation column, 2-first stripping column, 3-second extractive distillation column, 4-second stripping column, W1-butadiene rich feedstock, W2-polymeric grade pure butadiene product.
In FIG. 2, 5-suspension hood, 6-top reflux line, W1-butadiene rich feedstock, W3-extractant.
Detailed Description
The invention is described in further detail below with reference to the drawings and the specific examples. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be regarded as being isolated, and they may be combined with each other to achieve a better technical effect. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values.
The calculation formula for butadiene yield in each example is as follows:
the process flows of examples 1 to 10 are shown in FIG. 1, schematic diagrams of a first extraction rectifying tower and a second extraction rectifying tower are shown in FIG. 2, suspension covers are arranged at a plurality of positions of the extraction rectifying towers, stainless steel supports are coated by the suspension covers through screens with a certain mesh number, polymerization inhibitors are loaded in the suspension covers, and the mesh number of the suspension covers is shown in Table 5. In the examples, the raw materials are materials rich in butadiene, and the process operating conditions of the first extractive distillation column, the first stripping column, the second extractive distillation column and the second stripping column are shown in table 1, table 2, table 3 and table 4 respectively, and the operating pressures of the first extractive distillation column, the first stripping column, the second extractive distillation column and the second stripping column are normal pressures. The component contents were measured by gas chromatography, and the results are shown in Table 6.
TABLE 1
TABLE 2
Table 3.
TABLE 4 Table 4
TABLE 5
TABLE 6
Claims (8)
1. A method for separating butadiene by using an extractive distillation column, comprising the steps of:
(1) Feeding the raw material rich in butadiene into a first extraction rectifying tower to obtain a tower kettle material rich in butadiene, and separating butane butene from the tower top; wherein, the weight ratio of the raw materials to the extractant is 1: (4-20), the operating pressure is normal pressure, the temperature of the tower bottom of the rectifying tower is 70-150 ℃, and the reflux ratio is 0.8-20;
(2) Feeding the tower kettle material obtained in the step 1) into a first stripping tower, and separating butadiene from an extracting agent to obtain tower top material containing butadiene, ethyl acetylene, vinyl acetylene and methyl acetylene; wherein the operating pressure is normal pressure, the temperature of the bottom of the stripping tower is 60-200 ℃, and the reflux ratio is 1-6;
(3) The tower top material obtained in the step 2) enters a second extraction rectifying tower to obtain a tower top material rich in butadiene; wherein the feeding weight ratio of butadiene to extractant is 1: (4-20), the operating pressure is normal pressure, the temperature of the tower bottom of the rectifying tower is 60-150 ℃, and the reflux ratio is 1-10;
(4) Feeding the tower top material obtained in the step 3) into a second stripping tower, removing heavy components in the material at the tower bottom, removing trace propyne at the tower top, and distilling a polymerization-grade pure butadiene product from the side line of the stripping tower; wherein the operating pressure is normal pressure, the reflux ratio is 1-6, and the temperature of the bottom of the stripping tower is 40-100 ℃;
the extraction rectifying column comprises a rectifying column body, wherein a feed inlet is formed in the middle of the rectifying column body, a solvent inlet is formed in a position, close to the top of the rectifying column body, a column bottom pipeline is arranged at the bottom of the rectifying column body, a kettle liquid pump and a heater are connected to the column bottom pipeline, a reflux liquid inlet is formed in the top of the rectifying column body, the top of the rectifying column body is sequentially connected with a reflux pump through a pipeline, a liquid outlet of the reflux pump is respectively connected with a reflux liquid inlet and a product tank, and the extraction rectifying column is characterized in that a plurality of suspension covers for loading polymerization inhibitors are arranged in the rectifying column body and on top reflux pipelines and are composed of 10-80 mesh screens coated stainless steel supports.
2. The method for separating butadiene by using an extractive distillation column according to claim 1, wherein a suspension cover is uniformly arranged at the top of the column, below the feed inlet, on the column body and on the column bottom.
3. The separation method according to claim 1, wherein in the step (1) and the step (3), the polymerization inhibitor loaded in the suspension cover is mainly nitrite, and one or more of nitroxide free radicals, phenols, hydroxylamines, phosphites, nitro groups and amines are added in an auxiliary manner in the first extraction rectifying tower and the second extraction rectifying tower.
4. The separation method according to claim 1, wherein in the step (1) and the step (3), the extractant is any one of dimethylformamide, N-methylpyrrolidone, acetonitrile, and an aqueous acetonitrile solution having a water content of 5 to 15 wt%.
5. The separation method according to claim 1, wherein in the step (1), the feed weight ratio of the raw material to the extractant is 1: (7-9), the temperature of the tower bottom of the rectifying tower is 70-140 ℃ and the reflux ratio is 0.8-4.
6. The separation method according to claim 1, wherein in the step (2), the temperature of the bottom of the stripping column is 60-150 ℃ and the reflux ratio is 1-3.
7. The separation process of claim 1 wherein in step (3) the feed weight ratio of butadiene to extractant is 1: (4-8), the temperature of the tower bottom of the rectifying tower is 70-140 ℃ and the reflux ratio is 1-3.
8. A separation process according to claim 3, wherein in step (4), the stripper bottoms temperature is 40-65 ℃ and the reflux ratio is 1-3.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3851010A (en) * | 1972-01-28 | 1974-11-26 | Snam Progetti | Process for the separation of isoprene |
| US3860496A (en) * | 1970-12-29 | 1975-01-14 | Snam Progetti | Process for the recovery of isoprene from mixtures containing the same |
| CN1160034A (en) * | 1996-03-20 | 1997-09-24 | 中国石油化工总公司 | Method for separation of cracking C5 fraction |
| JP2004331599A (en) * | 2003-05-09 | 2004-11-25 | Nippon Shokubai Co Ltd | Method for distilling (meth)acrylic acid and/or its ester |
| JP2005220093A (en) * | 2004-02-06 | 2005-08-18 | Daiyanitorikkusu Kk | Distillation column for acrylonitrile production |
| CN101423450A (en) * | 2007-10-31 | 2009-05-06 | 中国石油化工股份有限公司 | Method for separating carbon 5 fraction by NMP method and one-stage extraction and rectification |
| CN101805631A (en) * | 2010-05-07 | 2010-08-18 | 天津大学 | Variable pressure steam stripping method of C5 fraction extraction solvent |
| CN102452889A (en) * | 2010-10-22 | 2012-05-16 | 中国石油化工股份有限公司 | Method for extracting butadiene from dimethylfomamide and mixture thereof |
| CN107304078A (en) * | 2016-04-20 | 2017-10-31 | 武汉理工大学 | A kind of environmentally friendly delayed release polymeric thing antisludging agent and preparation method thereof |
| CN107879881A (en) * | 2016-09-29 | 2018-04-06 | 中国石油化工股份有限公司 | A kind of separation method of polymerization grade isoprene |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8076526B2 (en) * | 2009-03-30 | 2011-12-13 | Lyondell Chemical Technology | Extractive distillation of conjugated diene |
-
2018
- 2018-12-14 CN CN201811533074.6A patent/CN111320520B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3860496A (en) * | 1970-12-29 | 1975-01-14 | Snam Progetti | Process for the recovery of isoprene from mixtures containing the same |
| US3851010A (en) * | 1972-01-28 | 1974-11-26 | Snam Progetti | Process for the separation of isoprene |
| CN1160034A (en) * | 1996-03-20 | 1997-09-24 | 中国石油化工总公司 | Method for separation of cracking C5 fraction |
| JP2004331599A (en) * | 2003-05-09 | 2004-11-25 | Nippon Shokubai Co Ltd | Method for distilling (meth)acrylic acid and/or its ester |
| JP2005220093A (en) * | 2004-02-06 | 2005-08-18 | Daiyanitorikkusu Kk | Distillation column for acrylonitrile production |
| CN101423450A (en) * | 2007-10-31 | 2009-05-06 | 中国石油化工股份有限公司 | Method for separating carbon 5 fraction by NMP method and one-stage extraction and rectification |
| CN101805631A (en) * | 2010-05-07 | 2010-08-18 | 天津大学 | Variable pressure steam stripping method of C5 fraction extraction solvent |
| CN102452889A (en) * | 2010-10-22 | 2012-05-16 | 中国石油化工股份有限公司 | Method for extracting butadiene from dimethylfomamide and mixture thereof |
| CN107304078A (en) * | 2016-04-20 | 2017-10-31 | 武汉理工大学 | A kind of environmentally friendly delayed release polymeric thing antisludging agent and preparation method thereof |
| CN107879881A (en) * | 2016-09-29 | 2018-04-06 | 中国石油化工股份有限公司 | A kind of separation method of polymerization grade isoprene |
Non-Patent Citations (2)
| Title |
|---|
| 丁二烯萃取精馏塔的优化;魏肖玲;石化技术与应用(第01期);第43-45页 * |
| 丁二烯装置萃取系统运行周期缩短原因及措施;郑建桥;;广州化工(第19期);第151-152，转195页 * |
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