CN1183399A - Method for recovering ethene from dilute ethene-contg. gas - Google Patents
Method for recovering ethene from dilute ethene-contg. gas Download PDFInfo
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- CN1183399A CN1183399A CN 95117068 CN95117068A CN1183399A CN 1183399 A CN1183399 A CN 1183399A CN 95117068 CN95117068 CN 95117068 CN 95117068 A CN95117068 A CN 95117068A CN 1183399 A CN1183399 A CN 1183399A
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- gas
- adsorber
- ethylene
- desorption
- ethene
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Abstract
An adsorption apparatus using tube-type adsorber as adsorbing separator features that a temp and pressure changing process is used to recover ethylene (99.5% in purity) from the gas containing less ethylene, which is conventionally used as fuel or vent gas of oil refinery or chemical plant. Its advantages are high yield (more than 85%), simple process, and high automation level.
Description
The invention belongs to mixed gas separation and field of purification, particularly from petrochemical process, selection fractionation by adsorption in contained rare ethylene gas of act as a fuel at present gas or emptying is reclaimed ethene.
Acting as a fuel at present from oil refining apparatus and chemical plant installations as everyone knows, the method for separating and reclaiming ethylene comprises separation by deep refrigeration contained rare ethylene gas of gas or emptying, middle cold oil absorption process, the clathrate separation method, the decompressor method, the transformation adsorption method of separation, method such as solvent extraction process and ARS, the CN92112397.3 patent is with adsorption separating method separating and reclaiming ethylene from catalytic cracked dry gas, this patent is done a lot of work to the research of sorbent material, and the exploitation of process unit flow process has been carried out research and obtained effect preferably.
The objective of the invention is on the basis of CN92112397.3, further provide and reclaim required technical process and the main equipment of ethylene industry device, realize industrialized purpose thereby reach, present method can reach and enlarge the scope that this device is handled unstripped gas simultaneously, improves the purpose that reclaims the ethylene concentration and the rate of recovery.
Adsorption separating method provided by the present invention is to use two kinds of solid adsorbent, adopt the adsorption process of two sections of feed gas preprocessing and ethylene recovery, utilize the method for alternating temperature transformation or alternating temperature, used main equipment one adsorber is the shell and tube adsorber, sees accompanying drawing 2, arranges the tube bank that many pipes are formed in enclosure interior, solid adsorbent is housed in the pipe, it is interior by carrying out fractionation by adsorption from managing to contain rare ethylene gas, and feeding heating medium in housing when heat is taken off feeds heat-eliminating medium in the housing during cooling.Because the present invention has adopted shell and tube adsorber and time variable control, make this processing method realize that industrialization becomes possibility, unstripped gas is the mixed gas that contains 3-45% (volume) ethene that obtains from refinery and chemical plant, other component is C
3, C
4, H
2S, water vapor, CO, CO
2, C
2H
6, C
2H
2, CH
4, N
2, H
2With oxygen of trace etc., these gas mixtures are from catalytic cracked dry gas, catalytic pyrolysis dry gas, thermally splitting dry gas, coking dry gas, the mixed gas that contains rare ethene that discharge in ethylene oxide device tail gas and refinery and chemical plant.
Processing method of the present invention is divided into feed gas preprocessing part and ethylene recovery part, and preprocessing part adopts acticarbon to select absorption C
3Or C
3Above hydro carbons and sulfide are removed these components from mixing raw material gas, ethene, ethane etc. are separated with them than light constituent; Ethylene recovery partly adopts copper-loaded and silver metal ionic adsorbent of molecular sieve, and optionally ethylene adsorption is separated ethene from the mixed gas of compositions such as ethane, methane, hydrogen, carbon monoxide and carbonic acid gas, thereby reaches the purpose that reclaims ethene.Two or more shell and tube adsorbers that acticarbon is housed of feed gas preprocessing part, when one of them adsorber adsorbs, other adsorber is in the different operating stage of release, desorption, blast-cold, preceding absorption and string absorption, the mutual blocked operation of a plurality of beds during to next operational cycle, each adsorber all experiences each above-mentioned stage, the action of valve is controlled by program controller all according to preset time; Auto-switch, two or more shell and tube adsorbers that adsorbent of molecular sieve is housed of ethylene recovery part, when one of them adsorber adsorbs, other adsorber is in release, flushing, heat is taken off, vacuumize, each stage of blast-cold and pressurising, the mutual blocked operation of a plurality of beds during to next operational cycle, each adsorber all experiences each above-mentioned stage, just stagger in time, the action of valve is all according to preset time, by sequence controller control auto-switch, the ethylene concentration that is reclaimed reaches more than 99.5% (V), the ethylene recovery rate reaches more than 85% (V), and the operational condition of feed gas preprocessing part is: adsorption temp is a room temperature to 60 ℃ during absorption; Adsorptive pressure is 0.1-3.0MPa (absolute pressure); When volume space velocity is 50-2000
-1During desorption: desorption temperature is 70-300 ℃; Desorption pressure is normal pressure and purges with nitrogen or absorption tail gas; Or vacuumize; The operational condition of ethylene recovery part is: when volume space velocity is 50-2000 in the adsorption process
-1Adsorptive pressure is 0.1-3.0MPa (absolute pressure); Adsorption temp is a room temperature to 60 ℃; Desorption pressure is that normal pressure is to 0.005MPa in the desorption process; Desorption temperature is 70-200 ℃; Desorption method is used and is heated, or vacuumizes and add the method for heat integration; Processing method of the present invention is referring to accompanying drawing 1, when unstripped gas enters the pre-treatment adsorber D that gac is housed and adsorbs, adsorber E is in the different steps of release, desorption, blast-cold, preceding absorption, string absorption, two mutual blocked operations of adsorber during to next operational cycle, the action of valve is controlled by program controller, now with regard to an adsorber D in a loop cycle the content of program representation present method of process: feed gas preprocessing partly comprises D, E, F ... a plurality of shell and tube adsorbers, the unstripped gas that contains rare ethene passes through valve D under adsorptive pressure
1Enter adsorber D, inhale residual air then by valve D
4Enter the ethylene recovery part, in the D adsorber, C
3And C
3Above hydro carbons and sulfide are attracted on the acticarbon, when sorbent material when saturated, close D
1, D
4, open D
2, D bed release this moment, beginning heat is taken off after the release, opens D
8, D
9Feed heating medium, open D simultaneously
5, D
2Utilize the suction residual air of ethylene recovery part to purge bed, after reaching desorption temperature, close D
8And D
9Valve takes off in heat and the D bed to be carried out the blast-cold stage after finishing, and opens D
10And D
11Valve leads to water coolant, in order to accelerate the adsorption bed speed of cooling, still utilizes the suction residual air of ethylene recovery part the D bed to be purged D
5And D
2Valve is still opened, and when the D bed tempertaure was reduced to normal temperature, purging finished, and closed water intaking valve D
10, open D
1And D
3Feed unstripped gas and begin preceding absorption, when not containing ethene in the gas that comes out, then put into flare system or gas holder, when just having contained ethene in the gas that comes out, then finished preceding absorbing process process, close D
1And D
3Valve, this moment, the E bed proceeded to the final stage of absorption, in order to prevent C
3Enter the ethylene recovery part, the gas after the absorption of E bed enters the ethylene recovery part again behind the D bed, enters the string absorption phase this moment.Close E
4, open D
6And D
4After string absorption finished, the D bed began the operation of next cycle again.The ethylene recovery part comprises that also a plurality of shell and tube adsorbers are A, B, and C ..., when an adsorber carried out adsorption operations, other adsorber was in then that release, flushing, heat are taken off, vacuumized, each stage of blast-cold, pressurising.Under adsorptive pressure and temperature, enter the A bed through pretreated unstripped gas, open A this moment by the bottom
1And A
6, ethene is attracted on the A bed, and the component that is not adsorbed is promptly inhaled residual air and as blast-cold gas the B bed is carried out blast-cold, B
3And B
5Open, the suction residual air behind the B bed after the absorption of A bed is finished, is closed A as the sweep gas of preprocessing part
1, A
6Still open, promptly enter the release stage, make A bed pressure reduce to normal pressure.After release is finished, utilize the ethene among the product jar F that the A bed is washed, open A
2, purge gas is still through the B bed, makes ethylene absorption in the purge gas on the B bed, unloads to calm the anger and purge gas is put into flare system or gas holder behind the B bed, and purge gas is called the flushing ratio with the ratio that purge gas adds product gas, and the purity of product is high more, washes higher than more.The flushing of A bed finishes, and closes A
2And A
6, begin heat this moment takes off, and opens A
8And A
9Feed heating medium, open A
4The A bed is vacuumized, after the A bed is heated to certain temperature, close A
8And A
9, the A bed still vacuumizes, and when reaching certain vacuum tightness, closes A
4, to finish heat this moment and take off and vacuumize, the ethene on A bed desorption basically gets off, and opens A
10And A
11Feed water coolant, the A bed is cooled off, utilize the suction residual air of C bed to carry out blast-cold simultaneously, when bed temperature was reduced to normal temperature, blast-cold was finished, and closed A
10, entering next stage carries out pressurising, A to bed
3And A
7Open, unloading of C bed calmed the anger, and purge gas is through A
3Enter the A bed, by A
7Put into flare system or gas holder, the release of C bed is after flushing is finished, the pressurising process of A bed also finishes, promptly finished the absorption of A bed, the operating process of desorption and blast-cold, at this moment, the A bed is circulated to next cycle again and carries out adsorption operations, remaining a plurality of bed will experience said process too, just will stagger in time, and all valves are according to the given time, by sequence controller control, valve open and close whole automatizations.
The effect that the present invention reached is owing to adopted the main equipment of shell and tube adsorber as fractionation by adsorption ethene from contain rare ethylene gas, thereby present refinery and chemical plant generally can be acted as a fuel burn or the mixed gas that contains 3-45% (volume) ethene of emptying in ethene recycled, ethylene product purity can reach more than 99.5% (wt), yield of ethene can reach more than 85% (V), technical process of the present invention is simple, equipment used is easy to make, equipment material is a carbon steel, three-waste free pollution, it is big to reclaim the ethylene unit turndown ratio, the level of automation height is easy to realize industrialization.
Accompanying drawing and explanation thereof:
Accompanying drawing 1 is the schematic flow sheet that reclaims ethene from contain rare ethylene gas.
In the accompanying drawing 1:
Preprocessing part:
1. when unstripped gas adsorbed, valve 1,4 left
2. active-carbon bed release, during heat degassing release, valve 2 leaves
3. when active-carbon bed initial stage suction residual air heat was taken off, valve 2,5 left
4.PU-2 unloading of adsorbent bed calmed the anger, during the blast-cold of flushing tail gas, valve 2,5 leaves
5. when adsorbing before the product ethene, valve 1,3 leaves
During string absorption, valve 4,6 leaves
Recovery part: pre-treatment and recovery part:
During absorption, during valve 1,6 Kai Retuo, valve 8,9 leaves
During release, when blast-cold left by valve 6, valve 10,11 left
During flushing, A left by valve 2,6, B, C ethylene recovery adsorber
Heat is taken off when finding time, and D left by valve 4, E pre-treatment adsorber
During blast-cold, F product jar left by valve 3,5
During pressurising, the J vacuum compressor left by valve 3,7
Accompanying drawing 2 is shell and tube adsorber synoptic diagram
The 1-charging bole
2, the 6-gas inlet and outlet
The 4-tubulation
Import of 3-thermal medium and cold media outlet
Cold medium import of 5-and thermal medium outlet
Embodiment 1
Adopt the shell and tube adsorber in the device shown in the accompanying drawing 1, utilize alternating temperature, voltage-transforming method to produce high concentration ethylene from contain rare ethylene gas, the raw material composition sees Table-1.
Table-1
| Gas composition | ??N 2 | ???O 2 | ??H 2S | ??H 2O | ??CO | CO 2 | ??H 2 | ??G 1 | ???C 2 | ???C 2 | ??C 3 | ??C 3 | ?∑C 4 |
| ?V％ | ?27.00 | ?1.700 | ?0.002 | ??0.05 | ?0.40 | 1.20 | ?40.00 | ?24.00 | ??2.30 | ??3.00 | ?0.078 | ?0.12 | ??0.15 |
Unstripped gas is removed C after pre-treatment
3And C
3Above component, the preprocessing part operational condition is as follows: adsorption temp is a room temperature, adsorptive pressure is 3.0MPa; The charging air speed is 2000 o'clock
-1, C in pretreated gas
3And C
3Above component is reduced to 20ppm, and see Table 2 concrete the composition.
Table-2
| Gas composition | ???N 2 | ??O 2 | ????H 2S | ??H 2O | ??CO | ??CO 2 | ??H 2 | ??C 1 | ?C 2 | ??C 2 | ?C 3And ∑ C 4 |
| ?V％ | ?27.20 | ?1.70 | ??0.001 | ?0.007 | ?0.40 | ?1.25 | ?40.1 | ?24.0 | ?2.30 | ?3.04 | ???0.002 |
Gas in the table 2 enters the ethylene recovery part, is room temperature at adsorption temp; Adsorptive pressure is 2.9MPa; The charging air speed is 2000 o'clock
-1Desorption temperature is 150 ℃; Desorption pressure is-0.089MPa; Flushing is than being under 80% the operational condition, and recovery ethene purity reaches 99.5% (V), more than the yield 85% (V).
Embodiment 2
Adopt the shell and tube adsorber in the device shown in the accompanying drawing 1, utilize alternating temperature, voltage-transforming method to carry out the technological process of fractionation by adsorption, produce high concentration ethylene from contain rare ethylene gas, the raw material composition sees Table-3.
Table-3
| Gas composition | ????N 2 | ????O 2 | ??H 2S | ??H 2O | ??CO | CO 2 | ??H 2 | ??C 1 | ??C 2 | ???C 2 | ??C 3 | ???C 3 | ??∑C 4 |
| ?V％ | ??15.12 | ???0.67 | ?0.002 | ?0.05 | ?0.47 | ?0.23 | ?43.11 | 17.63 | ??10.12 | ??11.45 | ?0.11 | ???0.58 | ??0.46 |
Unstripped gas is removed C after pre-treatment
3And C
3Above component, the preprocessing part operational condition is as follows: adsorption temp is 45 ℃; Adsorptive pressure is 0.7MPa; The charging air speed is 275 o'clock
-1, C in pretreated gas
3And C
3Above component is less than 20ppm, and see Table-4 concrete the composition.
Table-4
| Gas composition | ????N 2 | ??O 2 | ?H 2O | ??CO | ?CO 2 | ??H 2 | ??C 1 | ??C 2 | ??C 2 |
| ??V％ | ??15.31 | ??0.69 | 0.002 | ?0.49 | ?0.24 | ?43.64 | 17.86 | 10.25 | 11.50 |
Gas in the table-4 enters the ethylene recovery part, is 45 ℃ at adsorption temp; Adsorptive pressure is 0.68MPa; The charging air speed is 275 o'clock
-1Desorption temperature is 148 ℃; Desorption pressure is-0.08MPa; Flushing is than being under 56% the operational condition, and recovery ethene purity reaches 99.5% (V); More than the yield 85.6% (V).
Adopt the shell and tube adsorber in the device shown in the accompanying drawing 1, utilize alternating temperature, voltage-transforming method to carry out the adsorptive separation technology process, produce high concentration ethylene from contain rare ethylene gas, the raw material composition sees Table-5.
Table-5
| Gas composition | ??N 2 | ??O 2 | H 2S | ??H 2O | ?CO | ??CO 2 | ??H 2 | ??C 1 | ??C 2 | ??C 2 | ??∑C 4 |
| ??V％ | 13.08 | ?0.008 | 0.002 | ?0.005 | ?0.40 | ?1.15 | ?1.09 | ?19.00 | ?20.10 | ?45.10 | ?0.02 |
Unstripped gas is removed C after pre-treatment
3And C
3Above component, the preprocessing part operational condition is as follows: adsorption temp is 60 ℃, adsorptive pressure is 1.5MPa; The charging air speed is 50 o'clock
-1, C in pretreated gas
3And C
3Above component is less than 20ppm, and see Table-6 concrete the composition.
Table-6
| Gas composition | ??N 2 | ??O 2 | H 2S | H 2O | ??CO | ??CO 2 | ??H 2 | ?????C 1 | ???C 2 | ??C 2 |
| ??V％ | 13.08 | ?0.008 | ?0.41 | ?1.20 | ?0.002 | ????1.10 | ??20.10 | ??44.89 |
Gas in the table-6 enters the ethylene recovery part, is 60 ℃ at adsorption temp; Adsorptive pressure is 0.2MPa; The charging air speed is 50 o'clock
-1Desorption temperature is 120 ℃; Desorption pressure is-0.08MPa; Flushing is than being under 40% the operational condition, and the recovery ethylene concentration reaches 99.6% (V), more than the total recovery 85% (V).
Claims (3)
1. method that from contain rare ethylene gas, reclaims ethene, it is characterized in that comprising feed gas preprocessing and ethylene recovery two portions, two or more shell and tube adsorbers that acticarbon is housed of feed gas preprocessing part, when one of them adsorber adsorbs, other adsorber is in release, desorption, blast-cold, the different operating stage of preceding absorption and string absorption, the mutual blocked operation of a plurality of adsorption bed during to next operational cycle, each adsorber all experiences each above-mentioned stage, the action of valve is controlled by program controller, auto-switch; Two or more shell and tube adsorbers that the adsorbent of molecular sieve that carries steel and silver is housed of ethylene recovery part, when one of them adsorber adsorbs, other adsorber is in release, flushing, heat is taken off, vacuumize, each stage of blast-cold and pressurising, the mutual blocked operation of a plurality of beds during to next operational cycle, each adsorber all experiences each above-mentioned stage, just stagger in time, the action of valve is all according to preset time, switch by the sequence controller by-pass valve control carries out automated operation, the ethylene concentration that reclaims with this method reaches more than 99.5% (V), the rate of recovery reaches more than 85% (V), the shell and tube adsorber is by arranging the tube bank that multitube is formed in the housing, solid adsorbent is housed in the pipe, when taking off, heat feeds heating medium in the housing, feed heat-eliminating medium during cooling in the housing, the magnetic ball is housed in the lower cover on the shell and tube adsorber.
2. the method that reclaims ethene from contain rare ethylene gas according to claim 1 is characterized in that the operational condition of feed gas preprocessing part is: the temperature during absorption is a room temperature to 60 ℃; Adsorptive pressure is 0.1-3.OMPa (absolute pressure); When volume space velocity is 50-2000
-1During desorption: desorption temperature is 70-300 ℃; Desorption pressure is normal pressure and purges with nitrogen or absorption tail gas; Or vacuumize; The operational condition that reclaims ethylene moiety is: the temperature during absorption is a room temperature to 60 ℃; Adsorptive pressure is 0.1-3.0MPa (absolute pressure); When volume space velocity is 50-2000
-1Desorption temperature is 70-200 ℃ in the desorption process; Desorption pressure is that normal pressure is to 0.005MPa (absolute pressure); During desorption with heating or vacuumize and add the method for heat integration.
3. method according to claim 1, it is characterized in that containing rare ethylene gas and comprise catalytic cracked dry gas, catalytic pyrolysis dry gas, thermally splitting dry gas, the coking dry gas, the mixed gas that contains 3-45% (V) ethene of ethylene oxide device tail gas and refinery and the emptying of chemical plant institute.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95117068A CN1048010C (en) | 1995-10-24 | 1995-10-24 | Method for recovering ethene from dilute ethene-contg. gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95117068A CN1048010C (en) | 1995-10-24 | 1995-10-24 | Method for recovering ethene from dilute ethene-contg. gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1183399A true CN1183399A (en) | 1998-06-03 |
| CN1048010C CN1048010C (en) | 2000-01-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95117068A Expired - Lifetime CN1048010C (en) | 1995-10-24 | 1995-10-24 | Method for recovering ethene from dilute ethene-contg. gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1048010C (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110184085A (en) * | 2019-06-11 | 2019-08-30 | 杨皓 | A kind of technique obtaining highly concentrated unsaturated hydrocarbons component from oven gas |
| CN113906001A (en) * | 2019-08-23 | 2022-01-07 | 昭和电工株式会社 | Process for recovery of olefins |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2044526U (en) * | 1988-05-24 | 1989-09-20 | 西北工业大学1008教研室 | Gds-type high-speed electric spark apparatus for processing deep hole |
| CA2092604A1 (en) * | 1992-11-12 | 1994-05-13 | Richard Swee-Chye Yeo | Hydrophilic, multicomponent polymeric strands and nonwoven fabrics made therewith |
| US5402692A (en) * | 1993-08-10 | 1995-04-04 | Bennett; Edward D. | Method of making blanking dies and punches having rounded edges |
| NO309487B1 (en) * | 1993-11-29 | 2001-02-05 | Boc Group Inc | Procedure for recycling the alkene |
-
1995
- 1995-10-24 CN CN95117068A patent/CN1048010C/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110184085A (en) * | 2019-06-11 | 2019-08-30 | 杨皓 | A kind of technique obtaining highly concentrated unsaturated hydrocarbons component from oven gas |
| CN113906001A (en) * | 2019-08-23 | 2022-01-07 | 昭和电工株式会社 | Process for recovery of olefins |
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| Publication number | Publication date |
|---|---|
| CN1048010C (en) | 2000-01-05 |
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