Combustion system for Flare Gas

Claim 2

A stack combustion tip for burning flare gas comprising: a. an enclosure at the top of the stack forming an open-end combustion chamber for receiving flare gas rising through the stack, b. the combustion chamber having an enlarged cross-section with respect to the cross-section of the stack and having at its lower peripHery openings to ambient air, c. and an oxygen-fuel burner mounted substantially centrally within the stack for projecting hot, turbulent elongated oxygen-fuel flames into the combustion chamber, said burner having a barrel portion defining an elongated burner chamber substantially centrally positioned within said stack and parallel to the longitudinal axis of said stack, a plurality of fuel passages for supplying streams of fuel, a plurality of oxygen passages for supplying streams of substantially pure oxygen, and means for cooling said burner chamber which chamber is positioned to receive said streams of fuel and oxygen supplied thereto from said fuel and oxygen passages, respectively, such that said fuel and oxygen streams are mixed and ignited in said burner chamber to produce said hot, turbulent elongated oxygen-fuel flame.

Claim 3

A stack combustion tip as specified in claim 1 wherein the oxygen-fuel burner is mounted coaxially of the stack and directly beneath the combustion chamber for projecting the flames vertically into the center of the chamber.

Claim 4

A stack combustion tip as specified in claim 2 wherein the oxygen-fuel burner projects the flames at greater velocity than that of the rising flare gas.

Claim 5

A stack combustion tip as specified in claim 1 wherein the enclosure is a frusto-conical section mounted at its small-diameter end on the stack, and the lower periphery of the section has said openings for admitting ambient air to the chamber.

Claim 6

A stack combustion tip as specified in claim 4 wherein the frusto-conical section is joined to and forms an extension of the stack, and the openings are peripherally spaced apertures in the section wall.

Claim 7

A stack combustion tip as specified in claim 1 wherein the enclosure is an open-end cylindrical member, and the lower end of the member is annularly spaced from the stack end to form peripheral openings to ambient air.

Claim 8

A stack combustion tip as specified in claim 6 wherein the cylindrical member also has wall openings laterally spaced around the cylindrical periphery opening to ambient air.

Claim 9

In a system for burning flare gas including an oxygen-fuel burner mounted substantially centrally within a cylindrical stack through which a flare gas flows to a combustion chamber of an enlarged cross-section with respect to the cross-section of the stack, said combustion chamber having openings in its lower periphery to ambient air and said oxygen fuel burner having a plurality of fuel passages for supplying streams of fuel, a plurality of oxygen passages for supplying streams of substantially pure oxygen, a barrel portion defining an elongated burner chamber positioned substantially centrally and parallel to the longitudinal axis of said stack and means for cooling said barrel portion which portion is positioned to receive said supplied streams of fuel and oxygen, the method which comprises: a. discharging into the combustion chamber from the stack a turbulent flame of burning fuel gas and oxygen at a velocity higher than that of the flare gas, b. causing flame-induced flow of ambient air into the combustion chamber from the lower periphery thereof and along the combustion chamber sides for mixing with the rising flare gas, and c. directing the flame vertically and centrally of the combustion chamber for optimum mixing and interaction of the mixed gases with the flame.

Claim 10

In a system for burning flare gas including an oxygen-fuel burner mounted substantially centrally within a cylindrical stack through which a flare gas flows to a combustion chamber of an enlarged cross-section with respect to the cross-section of the stack, said combustion chamber having openings in its lower periphery to ambient air and said oxygen fuel burner having a plurality of fuel passages for supplying streams of fuel, a plurality of oxygen passages for supplying streams of substantially pure oxygen, a barrel portion defining an elongated burner chamber positioned substantially centrally and parallel to the longitudinal axis of said stack and means for cooling said barrel portion which portion is positioned to receive said supplied streams of fuel and oxygen, the method which comprises: a. discharging into the combustion chamber from the stack a turbulent flame of burning fuel gas and oxygen at a velocity higher than that of the flare gas, b. causing flame-induced flow of ambient air into the combustion chamber from the lower periphery thereof and along the combustion chamber sides for mixing with the rising flare gas, and c. directing the flame vertically and centrally of the combustion chamber for optimum mixing and interaction of the mixed gases with the flame.

Claim 11

The method as specified in claim 8 wherein the induced air is caused to flow into the lower peripheral part of the combustion chamber for upward flow in diverging directions.

Claim 12

The method as specified in claim 8 wherein the oxygen-fuel flame is projected turbulently in concentric relation to the rising flare gas from the stack and the inducted air respectively for interacting relationship in the combustion chamber.

Claim 13

The method as specified in claim 8 wherein the rate of flow of flare gas in the stack is sensed, and the supply of fuel gas and oxygen for the flame is adjusted according to the sensed flow rate.