US4241230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for the selective hydrogenation of acetylene present in ethylene product streams
Assignee: Mobil Oil AS
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Filing: 1979-11-19
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Granted: 1980-12-23
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Expires: 1999-11-19
Abstract
Abstract Acetylene contained in an ethylene product stream in minor amounts is selectively hydrogenated to ethylene in the presence of suitable catalysts in a two stage converter having a primary reactor stage providing hydrogenation of a portion of the acetylene present in the stream in series with a secondary reactor stage providing hydrogenation of substantially all of the remaining unreacted acetylene. Overall process control is achieved by adjusting the molar ratio of hydrogen to acetylene in the feed stream for the primary reactor stage in response to feedforward information from an analyzer for the primary stage feed stream and feedback information from an analyzer for the primary stage effluent stream to provide a primary stage effluent of substantially constant acetylene content. The substantially constant acetylene content of the primary reactor stage effluent allows operation of the secondary reactor stage to be optimized to provide for maximum ethylene recovery and a secondary stage stream effluent having a level of acetylene therein within desired process specifications.
Inventors
- 👤 B. M. Drinkard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:41
CPC Classifications
B; B01; B01J; B01J19/00; B01J19/0006; B01J19/0033; B01J8/00; B01J8/001; C; C07; C07C; C07C5/00; C07C5/02; C07C5/08; C07C5/09
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
105 words
A method of operating an acetylene converter for an ethylene plant by hydrogenating the acetylene in a two-stage reactor, having primary and secondary stages, each having therein a hydrogenation catalyst, comprising: (a) substantially optimizing the operation of the secondary stage of the reactor to produce a relatively low concentration of acetylene in its output effluent by maintaining the concentration of acetylene in the feed stream to the secondary stage substantially constant; and (b) operating the primary stage of the reactor to provide an output effluent having a substantially constant acetylene content, which is then directed as an input to the secondary stage of the reactor.
Claim 2
Independent Claim
105 words
A method of operating an acetylene converter for an ethylene plant by hydrogenating the acetylene in a two-stage reactor, having primary and secondary stages, each having therein a hydrogenation catalyst, comprising: (a) substantially optimizing the operation of the secondary stage of the reactor to produce a relatively low concentration of acetylene in its output effluent by maintaining the concentration of acetylene in the feed stream to the secondary stage substantially constant; and (b) operating the primary stage of the reactor to provide an output effluent having a substantially constant acetylene content, which is then directed as an input to the secondary stage of the reactor.
Claim 3
Dependent Claim
40 words
A method of operating an acetylene converter as claimed in claim 1, wherein the step of operating the primary stage of the reactor includes the step of adjusting the molar ratio of hydrogen to acetylene in the feed stream thereto.
Claim 4
Dependent Claim
42 words
A method of operating an acetylene converter as claimed in claim 2, wherein the step of operating the primary reactor stage includes the step of controllably adding hydrogen to the primary reactor stage feed stream through a control feed stream coupled thereto.
Claim 5
Dependent Claim
77 words
A method of operating an acetylene converter as claimed in claim 3, wherein the step of adjusting the molar ratio of hydrogen to acetylene in the feed stream to the primary reactor stage is controlled in response to feedback information from an analyzer for the primary stage effluent stream which indicates the concentration of acetylene therein and feedforward information from an analyzer for the primary stage feed stream which indicates the concentrations of hydrogen and acetylene therein.
Claim 6
Independent Claim
36 words
A method of operating an acetylene converter as claimed in claims 1 or 4, including controlling operation of the secondary reactor stage by adjusting the molar ratio of hydrogen to acetylene in the feed stream thereto.
Claim 7
Dependent Claim
39 words
A method of operating an acetylene converter as claimed in claim 5, including the step of controlling the operation of the secondary reactor stage by selectively adding hydrogen to its feed stream through a control feed stream coupled thereto.
Claim 8
Dependent Claim
71 words
A method of operating an acetylene converter as claimed in claim 6, wherein the concentration of hydrogen in the feed stream to the secondary reactor stage is controlled in response to feedback information from an analyzer for the secondary stage effluent stream which indicates the concentration therein of acetylene, and feedforward information from an analyzer for the secondary reactor stage feed stream which indicates the concentrations of hydrogen and acetylene therein.
Claim 9
Dependent Claim
81 words
A method of operating an acetylene converter as claimed in claim 1, including the steps of sensing the temperatures of the feed stream to the primary reactor stage, the feed stream to the secondary reactor stage, and the effluent stream of the secondary reactor stage, whereby both the primary and secondary reactor stages may be monitored to detect the temperature differentials thereacross and the potential onset of a thermal runaway in either stage caused by excessive conversion of ethylene to ethane.
Claim 10
Dependent Claim
79 words
A method of operating an acetylene converter as claimed in claim 3, including the steps of measuring the concentration of carbon monoxide being directed to the primary reactor stage feed stream through the control feed stream coupled thereto, and selectively adding carbon monoxide to the primary stage control feed stream in response to said carbon monoxide measurement therein to maintain the concentration of carbon monoxide in the primary stage feed stream to provide for maximum selectivity of the catalyst.
Claim 11
Dependent Claim
77 words
A method of operating an acetylene converter as claimed in claim 1, including the steps of measuring the concentration of carbon monoxide being directed to the secondary reactor stage feed stream through the secondary control feed stream, and selectively adding carbon monoxide to the secondary stage feed stream in response to said carbon monoxide measurement therein to maintain the concentration of carbon monoxide in the secondary stage feed stream to provide for maximum selectivity of the catalyst.
Claim 12
Dependent Claim
34 words
A method of operating an acetylene converter as claimed in claim 1, including the step of passing the feed stream to the primary reactor stage through a heat exchanger to selectively control its temperature.
Claim 13
Dependent Claim
34 words
A method of operating an acetylene converter as claimed in claim 1, including the step of passing the feed stream to the secondary reactor stage through a heat exchanger to selectively control its temperature.
Claim 14
Independent Claim
158 words
A system for operating an acetylene converter for an ethylene plant in which excessive acetylene in the ethylene plant output is hydrogenated to ethylene, comprising: (a) a primary reactor stage, having therein a hydrogenation catalyst, for partially hydrogenating acetylene in the ethylene plant output to ethylene; (b) a secondary reactor stage, coupled to receive the effluent from the primary reactor stage, for substantially completing the hydrogenation of acetylene to bring the acetylene concentration in the stream to within process specifications; (c) a control means for the primary reactor stage for operating the primary reactor stage in a manner to maintain the concentration of acetylene in its effluent stream relatively constant; and (d) a control means for the secondary reactor stage for substantially optimizing the operation of the secondary reactor stage on its feed stream having said relatively constant concentration of acetylene to produce a relatively low concentration of acetylene in the output effluent of the secondary reactor stage.
Claim 15
Independent Claim
158 words
A system for operating an acetylene converter for an ethylene plant in which excessive acetylene in the ethylene plant output is hydrogenated to ethylene, comprising: (a) a primary reactor stage, having therein a hydrogenation catalyst, for partially hydrogenating acetylene in the ethylene plant output to ethylene; (b) a secondary reactor stage, coupled to receive the effluent from the primary reactor stage, for substantially completing the hydrogenation of acetylene to bring the acetylene concentration in the stream to within process specifications; (c) a control means for the primary reactor stage for operating the primary reactor stage in a manner to maintain the concentration of acetylene in its effluent stream relatively constant; and (d) a control means for the secondary reactor stage for substantially optimizing the operation of the secondary reactor stage on its feed stream having said relatively constant concentration of acetylene to produce a relatively low concentration of acetylene in the output effluent of the secondary reactor stage.
Claim 16
Dependent Claim
82 words
A system for operating an acetylene converter as claimed in claim 13, including: (a) an analyzer means for the feed stream for the primary reactor stage for measuring the concentrations therein of hydrogen, acetylene and ethylene; (b) an analyzer means for the feed stream for the secondary reactor stage for measuring the concentrations therein of hydrogen, acetylene and ethylene; and (c) an analyzer means for the effluent stream of the secondary reactor stage for analyzing the concentrations therein of acetylene and ethylene.
Claim 17
Dependent Claim
92 words
A system for operating an acetylene converter as claimed in claim 14, wherein: (a) said control means for the primary reactor stage is responsive to feedforward information from a rate-of-flow transducer for the feed stream for the primary reactor stage and also the primary stage feed stream analyzer indicating the concentrations of hydrogen and acetylene therein, and feedback information from the analyzer for the feed stream of the secondary reactor stage indicating the concentration therein of acetylene to adjust the amount of hydrogen in the feed stream of the primary reactor stage.
Claim 18
Dependent Claim
72 words
A system for operating an acetylene converter for an ethylene plant as claimed in claim 15, including a carbon monoxide analyzer for measuring the concentration of carbon monoxide in the feed stream for the primary reactor stage, and said control means for the primary reactor stage includes means, responsive to the output of said carbon monoxide analyzer, to selectively add carbon monoxide to the control feed stream for the primary reactor stage.
Claim 19
Independent Claim
94 words
A system for operating an acetylene converter as claimed in claims 14 or 15, wherein: (a) said control means for the secondary reactor stage is responsive to feedforward information from a rate-of-flow transducer for the feed stream for the primary reactor stage and also the secondary stage feed stream analyzer indicating the concentrations of hydrogen and acetylene therein, and feedback information from the analyzer for the effluent stream of the secondary reactor stage indicating the concentration therein of acetylene to adjust the amount of hydrogen in the feed stream of the secondary reactor stage.
Claim 20
Dependent Claim
73 words
A system for operating an acetylene converter for an ethylene plant as claimed in claim 17, including a carbon monoxide analyzer for measuring the concentration of carbon monoxide in the feed stream for the secondary reactor stage, and said control means for the secondary reactor stage includes means, responsive to the output of said secondary feed stream analyzer, to selectively add carbon monoxide to the control feed stream for the secondary reactor stage.
References Cited (Backward Citations)
US2802889A
Cited
US2814653A
Cited
US3113980A
Cited
US3153679A
Cited
US3471582A
Cited
US3656911A
Cited
US3972804A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-23 | 1984-06-23 | 1984-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-23 | 1988-06-23 | 1988-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-23 | 1992-06-23 | 1992-12-23 | $7700.00 | Window Closed / Lapsed |