Staged gas injection system

A staged gas injection system for a flare tip that can discharge waste gas into a combustion zone downstream from the flare tip, comprising:

• a stage gas source;
• a first gas injection assembly, said first gas injection assembly being configured to inject a stage gas at a high flow rate and a high pressure into the combustion zone via a first discharge port and including a first gas injection nozzle fluidly connected to said stage gas source from which said stage gas is received by the first gas injection nozzle;
• and
• a second gas injection assembly, said second gas injection assembly configured to inject said stage gas at a low flow rate and a high pressure into the combustion zone via a second discharge port and including a second gas injection nozzle fluidly connected to said stage gas source from which said stage gas is received by the second gas injection nozzle,
• wherein said first gas injection assembly and said second gas injection assembly are spaced apart from each other and oriented in the same direction, a first central axis extending through the first discharge port offset from and extending parallel to a second central axis extending through the second discharge port, wherein said first discharge port and said second discharge port eject gas parallel to one another such that both said first discharge port and said second discharge port discretely inject gas into an inner tubular member such that the gases from the first gas injection nozzle and the second gas injection nozzle are mixed prior to injection into the combustion zone, and wherein the low flow rate means the first gas injection assembly and second gas injection assembly are configured such that, on a per nozzle basis, the low flow rate is one-half or less than the high flow rate.

A staged gas injection system for a flare tip that can discharge waste gas into a combustion zone, comprising:

• a first gas injection assembly, said first gas injection assembly being configured to inject gas at a high flow rate and a high pressure into the combustion zone via a first discharge port, and
• a second gas injection assembly, said second gas injection assembly configured to inject gas at a low flow rate and a high pressure into the combustion zone via a second discharge port,
• a third gas injection assembly, said third gas injection assembly configured to inject gas at a low flow rate and a high pressure into the combustion zone via a third discharge port, and
• wherein said first gas injection assembly, said second gas injection assembly and said third gas injection assembly are spaced apart from each other and oriented in the same direction, a first central axis extending through the first discharge port offset from and extending parallel to a second central axis extending through the second discharge port, wherein said first discharge port and said second discharge port eject gas parallel to one another such that said first discharge port, second discharge port and third discharge port discretely inject gas into an inner tubular member such that the gases from the first gas injection assembly, the second gas injection assembly, and third gas injection assembly are mixed prior to injection into the combustion zone.