US4369803A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control of fuel gas blending
Assignee: Applied Automation Inc
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Filing: 1981-01-28
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Granted: 1983-01-25
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Expires: 2001-01-28
Abstract
Abstract In a process in which a fuel gas stream having a high BTU content is mixed with a fuel gas stream having a low BTU content to form a mixed fuel gas stream, the flow rate of the high BTU content fuel gas stream is manipulated to maintain a desired BTU content for the mixed fuel gas stream unless such control based on the desired BTU content for the mixed fuel gas stream would result in condensation in the mixed fuel gas stream. If condensation would occur, then the flow rate of the high BTU content fuel gas stream is manipulated so as to maintain the actual dew point temperature of the mixed fuel gas stream below the actual temperature of the mixed fuel gas stream to prevent condensation.
Inventors
- 👤 Danny L. Furr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:29
CPC Classifications
F; F23; F23K; F23K5/00; F23K5/002; C; C10; C10K; C10K3/00; C10K3/06; C10L; C10L3/00; F17; F17D; F17D1/00; F17D1/02; F17D1/04; G; G05; G05D; G05D22/00; G05D22/02; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0324; Y10T137/0329; Y10T137/0346; Y10T137/2496; Y10T137/2499
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
334 words
Apparatus comprising: a burner means; means for combining a first fuel gas stream with a second fuel gas stream to form a mixed fuel gas stream, wherein said first fuel gas stream has a higher BTU content than said second fuel gas stream; means for supplying said mixed fuel gas stream to said burner means; means for establishing a first signal reprsentative of the actual BTU content of said mixed fuel gas stream; means for establishing a second signal representative of the desired BTU content of said mixed fuel gas stream; means for comparing said first signal and said second signal and for establishing a third signal responsive to the difference between said first signal and said second signal, wherein said third signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the actual BTU content of said mixed fuel gas stream substantially equal to the desired BTU content for said mixed fuel gas stream; means for establishing a fourth signal representative of the actual dew point temperature for said mixed fuel gas stream; means for establishing a fifth signal representative of the actual temperature of said mixed fuel gas stream; means for establishing a sixth signal representative of a desired difference between said fourth signal and said fifth signal; means for subtracting said sixth signal from said fifth signal to establish a seventh signal; means for comparing said fourth signal and said seventh signal and for establishing an eighth signal responsive to the difference between said fourth signal and said seventh signal, wherein said eighth signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the desired difference between said fourth signal and said fifth signal; means for establishing a ninth signal representative of the lower of said third and eighth signals; and means for manipulating the flow rate of said first fuel gas stream in response to said ninth signal.
Claim 2
Dependent Claim
334 words
Apparatus comprising: a burner means; means for combining a first fuel gas stream with a second fuel gas stream to form a mixed fuel gas stream, wherein said first fuel gas stream has a higher BTU content than said second fuel gas stream; means for supplying said mixed fuel gas stream to said burner means; means for establishing a first signal reprsentative of the actual BTU content of said mixed fuel gas stream; means for establishing a second signal representative of the desired BTU content of said mixed fuel gas stream; means for comparing said first signal and said second signal and for establishing a third signal responsive to the difference between said first signal and said second signal, wherein said third signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the actual BTU content of said mixed fuel gas stream substantially equal to the desired BTU content for said mixed fuel gas stream; means for establishing a fourth signal representative of the actual dew point temperature for said mixed fuel gas stream; means for establishing a fifth signal representative of the actual temperature of said mixed fuel gas stream; means for establishing a sixth signal representative of a desired difference between said fourth signal and said fifth signal; means for subtracting said sixth signal from said fifth signal to establish a seventh signal; means for comparing said fourth signal and said seventh signal and for establishing an eighth signal responsive to the difference between said fourth signal and said seventh signal, wherein said eighth signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the desired difference between said fourth signal and said fifth signal; means for establishing a ninth signal representative of the lower of said third and eighth signals; and means for manipulating the flow rate of said first fuel gas stream in response to said ninth signal.
Claim 3
Dependent Claim
106 words
Apparatus in accordance with claim 1 wherein said means for establishing said fourth signal comprises: means for establishing a tenth signal representative of the actual pressure of said mixed fuel gas stream; means for establishing a plurality of eleventh signals which are each respectively representative of the concentration of a component of said mixed fuel gas stream; means for establishing a plurality of twelfth signals which are each respectively representative of the relative volatility of a particular component in said mixed fuel gas stream; and means for establishing said fourth signal in response to said tenth, said plurality of eleventh, and said plurality of twelfth signals.
Claim 4
Dependent Claim
147 words
Apparatus in accordance with claim 1 wherein said means for manipulating the flow rate of said first fuel gas stream in response to said ninth signal comprises: means for establishing a tenth signal representative of the actual flow rate of said first fuel gas stream; means for comparing said ninth signal and said tenth signal and for establishing an eleventh signal responsive to the difference between said ninth signal and said tenth signal, wherein said eleventh signal is scaled so as to be representative of a valve position which will provide an actual flow rate of said first fuel gas streams substantially equal to the desired flow rate represented by said ninth signal; a control valve means operably located so as to control the flow rate of said first fuel gas stream; and means for providing said eleventh signal as a control signal to said control means.
Claim 5
Independent Claim
305 words
A method for controlling the mixing of a first fuel gas stream with a second fuel gas stream to form a mixed fuel gas stream, wherein said first fuel gas stream has a higher BTU content than said second fuel gas stream, said method comprising the steps of: establishing a first signal representative of the actual BTU content of said mixed fuel gas stream; establishing a second signal representative of the desired BTU content of said mixed fuel gas stream; comparing said first signal and said second signal and establishing a third signal responsive to the difference between said first signal and said second signal, wherein said third signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the actual BTU content of said mixed fuel gas stream substantially equal to the desired BTU content for said mixed fuel gas stream; establishing a fourth signal representative of the actual dew point temperature for said mixed fuel gas stream; establishing a fifth signal representative of the actual temperature of said mixed fuel gas stream; establishing a sixth signal representative of a desired difference between said fourth signal and said fifth signal; subtracting said sixth signal from said fifth signal to establish a seventh signal; comparing said fourth signal and said seventh signal and establishing an eighth signal responsive to the difference between said fourth signal and said seventh signal, wherein said eighth signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the desired difference between said fourth signal and said fifth signal; establishing a ninth signal representative of the lower of said third and eighth signals; and manipulating the flow rate of said first fuel gas stream in response to said ninth signal.
Claim 6
Independent Claim
305 words
A method for controlling the mixing of a first fuel gas stream with a second fuel gas stream to form a mixed fuel gas stream, wherein said first fuel gas stream has a higher BTU content than said second fuel gas stream, said method comprising the steps of: establishing a first signal representative of the actual BTU content of said mixed fuel gas stream; establishing a second signal representative of the desired BTU content of said mixed fuel gas stream; comparing said first signal and said second signal and establishing a third signal responsive to the difference between said first signal and said second signal, wherein said third signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the actual BTU content of said mixed fuel gas stream substantially equal to the desired BTU content for said mixed fuel gas stream; establishing a fourth signal representative of the actual dew point temperature for said mixed fuel gas stream; establishing a fifth signal representative of the actual temperature of said mixed fuel gas stream; establishing a sixth signal representative of a desired difference between said fourth signal and said fifth signal; subtracting said sixth signal from said fifth signal to establish a seventh signal; comparing said fourth signal and said seventh signal and establishing an eighth signal responsive to the difference between said fourth signal and said seventh signal, wherein said eighth signal is scaled so as to be representative of the flow rate of said first fuel gas stream required to maintain the desired difference between said fourth signal and said fifth signal; establishing a ninth signal representative of the lower of said third and eighth signals; and manipulating the flow rate of said first fuel gas stream in response to said ninth signal.
Claim 7
Dependent Claim
99 words
A method in accordance with claim 4 wherein said step of establishing said fourth signal comprises: establishing a tenth signal representative of the actual pressure of said mixed fuel gas stream; establishing a plurality of eleventh signals which are each respectively representative of the concentration of a component of said mixed fuel gas stream; establishing a plurality of twelfth signals which are each respectively representative of the relative volatility of a particular component in said mixed fuel gas stream; and establishing said fourth signal in response to said tenth, said plurality of eleventh, and said plurality of twelfth signals.
Claim 8
Dependent Claim
138 words
A method in accordance with claim 4 wherein said step of manipulating the flow rate of said first fuel gas stream in response to said ninth signal comprises: establishing a tenth signal representative of the actual flow rate of said first fuel gas stream; comparing said ninth signal and said tenth signal and establishing an eleventh signal responsive to the difference between said ninth signal and said tenth signal, wherein said eleventh signal is scaled so as to be representative of a valve position which will provide an actual flow rate of said first fuel gas streams substantially equal to the desired flow rate represented by said ninth signal; and providing said eleventh signal as a control signal to a control valve means operably located so as to control the flow rate of said first fuel gas stream.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-24 | 1986-07-26 | 1987-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-24 | 1990-07-26 | 1991-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-24 | 1994-07-26 | 1995-01-25 | $7700.00 | Window Closed / Lapsed |