US4139339A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flare gas stack with purge control
Assignee: Combustion Unlimited Inc
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Filing: 1977-02-17
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Granted: 1979-02-13
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Expires: 1997-02-17
Abstract
Abstract A purge control system for flare gas stacks is described in which provisions are made for start up, steady state or transient purge gas control, and for failure of the purge gas supply, and also takes into account variable windspeed at or near the top of the stack, flow or non-flow of purge gas and waste gas in the stack, ambient temperature and temperature of the advancing gaseous medium in the stack, oxygen content of the gas at a predetermined location in the stack, the system including provisions for pilot burner gas supply and ignition with protection against pilot burner operation under undesired conditions, an indicating panel being employed to advise the operator of the prevailing operating conditions so that, if desired, appropriate action can be taken by the operator.
Inventors
- 👤 John F. Straitz, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:10
CPC Classifications
F; F23; F23N; F23N1/00; F23N1/002; F23G; F23G5/00; F23G5/50; F23G7/00; F23G7/06; F23G7/08; F23G7/085; F23N5/00; F23N5/18
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
111 words
Control apparatus for a flare gas stack which comprises in combination with a flare gas stack a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas for controlled delivery of purge gas to said stack, a gas pilot burner for igniting of gas at the discharge end of the stack, and means for controlling the operation of said pilot burner, said means including a flow sensor for said stack for preventing activation of said pilot burner when no gas flow in said stack is sensed by said flow sensor.
Claim 2
Dependent Claim
111 words
Control apparatus for a flare gas stack which comprises in combination with a flare gas stack a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas for controlled delivery of purge gas to said stack, a gas pilot burner for igniting of gas at the discharge end of the stack, and means for controlling the operation of said pilot burner, said means including a flow sensor for said stack for preventing activation of said pilot burner when no gas flow in said stack is sensed by said flow sensor.
Claim 3
Dependent Claim
23 words
Control apparatus as defined in claim 1 in which said flow sensor is responsive to flow of waste combustible gas to said stack.
Claim 4
Dependent Claim
21 words
Control apparatus as defined in claim 1 which said flow sensor is responsive to flow of purge gas to said stack.
Claim 5
Dependent Claim
100 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas, a gas pilot burner for ignition of gas at the discharge end of the stack, and a windspeed indicator contiguous to said stack having a windspeed signal transmitter operated thereby, and means for controlling the operation of said pilot burner, said means being controlled by a signal from said windspeed signal transmitter.
Claim 6
Dependent Claim
100 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas, a gas pilot burner for ignition of gas at the discharge end of the stack, and a windspeed indicator contiguous to said stack having a windspeed signal transmitter operated thereby, and means for controlling the operation of said pilot burner, said means being controlled by a signal from said windspeed signal transmitter.
Claim 7
Dependent Claim
24 words
Control apparatus as defined in claim 4 in which said means also includes members for controlling the supply of purge gas to said stack.
Claim 8
Dependent Claim
33 words
Control apparatus as defined in claim 4 in which said means also includes members responsive to the temperature differential interiorly and exteriorly of said stack for controlling the activation of said pilot burner.
Claim 9
Dependent Claim
47 words
Control apparatus as defined in claim 4 in which a gas flow sensor is provided for said stack, said means also includes members responsive to a signal from said gas flow sensor for preventing activation of said pilot burner when no gas is flowing in said stack.
Claim 10
Dependent Claim
17 words
Control apparatus as defined in claim 4 in which indicating means is provided for said windspeed signal.
Claim 11
Dependent Claim
27 words
Control apparatus as defined in claim 4 in which a purge monitoring indicator is provided responsive to said windspeed signal, purge gas flow and waste gas flow.
Claim 12
Dependent Claim
37 words
Control apparatus as defined in claim 9 in which temperature sensors are provided for the temperature inside the stack and the ambient temperature, and said purge monitoring indicator is also responsive to the differential of said temperatures.
Claim 13
Dependent Claim
104 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas for controlled delivery of purge gas to said stack, a gas pilot burner for ignition of gas at the discharge end of the stack, and means for visually monitoring the conditions in said stack, said means including a visual indicator controlled by waste gas flow, purge gas flow and temperature conditions inside and outside the stack.
Claim 14
Dependent Claim
104 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas for controlled delivery of purge gas to said stack, a gas pilot burner for ignition of gas at the discharge end of the stack, and means for visually monitoring the conditions in said stack, said means including a visual indicator controlled by waste gas flow, purge gas flow and temperature conditions inside and outside the stack.
Claim 15
Dependent Claim
21 words
Control apparatus as defined in claim 11 in which said visual indicator is also controlled by the windspeed adjacent said stack.
Claim 16
Dependent Claim
43 words
Control apparatus as defined in claim 11 in which said portion has a part indicating unsafe conditions for pilot burner activation and a part indicating safe conditions for pilot burner activation, the pilot burner being locked against activation in said unsafe indicating part.
Claim 17
Dependent Claim
37 words
Control apparatus as defined in claim 11 in which oxygen content sensing apparatus is provided in communication with the interior of said stack, and said panel has oxygen content indicating means activated by said oxygen sensing apparatus.
Claim 18
Dependent Claim
37 words
Control apparatus as defined in claim 11 in which a windspeed indicator contiguous to said stack has a signal transmitter operated thereby, and said monitoring panel has a windspeed indicator responsive to the signal from said transmitter.
Claim 19
Dependent Claim
117 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas, and waste gas flow sensing and signaling members, means for controlling the supply of purge gas to said stack, said means including valve members for controlling purge gas delivery, members responsive to non-flow of waste gas for permitting purge gas flow, and windspeed sensing and signaling members, control members for said valve members controlled by said windspeed sensing and signaling members for controlling said purge gas delivery valve members.
Claim 20
Dependent Claim
117 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas, and waste gas flow sensing and signaling members, means for controlling the supply of purge gas to said stack, said means including valve members for controlling purge gas delivery, members responsive to non-flow of waste gas for permitting purge gas flow, and windspeed sensing and signaling members, control members for said valve members controlled by said windspeed sensing and signaling members for controlling said purge gas delivery valve members.
Claim 21
Dependent Claim
40 words
Control apparatus as defined in claim 13 in which temperature sensors are provided for the temperature inside the stack and the ambient temperature, and said control members for said valve members are also controlled by the difference between said temperatures.
Claim 22
Dependent Claim
98 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas, and means for controlling the supply of purge gas to said stack, said means including valve members for controlling purge gas delivery, windspeed sensing and signaling members, and control members for said valve members controlled by said windspeed sensing and signaling members for controlling said purge gas delivery valve members.
Claim 23
Dependent Claim
98 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, a connection to said stack from a supply of purge gas, and means for controlling the supply of purge gas to said stack, said means including valve members for controlling purge gas delivery, windspeed sensing and signaling members, and control members for said valve members controlled by said windspeed sensing and signaling members for controlling said purge gas delivery valve members.
Claim 24
Dependent Claim
117 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, waste gas flow sensing members, a connection to said stack from a supply of purge gas for controlled delivery of purge gas to said stack, purge gas flow sensing members, a gas pilot burner for ignition of gas at the discharge end of the stack, and a monitoring panel for indicating conditions in said stack, said panel having waste gas and purge gas flow indicating members, and means for indicating the relative location of the gas/air interface in said stack.
Claim 25
Dependent Claim
117 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, waste gas flow sensing members, a connection to said stack from a supply of purge gas for controlled delivery of purge gas to said stack, purge gas flow sensing members, a gas pilot burner for ignition of gas at the discharge end of the stack, and a monitoring panel for indicating conditions in said stack, said panel having waste gas and purge gas flow indicating members, and means for indicating the relative location of the gas/air interface in said stack.
Claim 26
Dependent Claim
96 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, temperature sensing means in said stack, a connection to said stack for supplying transient purge gas to said stack controlled by said temperature sensing means, a connection to said stack for supplying steady state purge gas to said stack, purge gas flow sensors for each of said purge gas connections, and means for indicating the delivery of purge gas.
Claim 27
Dependent Claim
96 words
Control apparatus for a flare gas stack which comprises, in combination with a flare gas stack, a connection to said stack from a supply of waste combustible gas for combustion at the discharge end of the stack, temperature sensing means in said stack, a connection to said stack for supplying transient purge gas to said stack controlled by said temperature sensing means, a connection to said stack for supplying steady state purge gas to said stack, purge gas flow sensors for each of said purge gas connections, and means for indicating the delivery of purge gas.
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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) | 1982-02-12 | 1982-08-14 | 1983-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-12 | 1986-08-14 | 1987-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-12 | 1990-08-14 | 1991-02-13 | $7700.00 | Window Closed / Lapsed |