Abstract: An improved water seal drum for gas comprising a vessel containing seal water, a gas introducing pipe extending downward from the upper part of the vessel, the lower end of the pipe opening beneath the water level, and a gas discharging pipe at the top of the vessel; characterized in that the gas introducing pipe is equipped with gas dispersing pipes having multiple nozzles for releasing the gas at a location above the lower end of the gas introducing pipe but beneath the water level. The drum enables stable water seaing of gas in a wide range of gas flow rates, and is particularly useful as a water seal drum for inflammable waste gases to be burned in a flare stack.

Abstract: Stable burning of waste combustible gases is assured even in a strong wind by using an improved ground flare stack. The stack, which is a cylinder containing burner nozzles therein, is provided with a fence surrounding the lower part of the stack, a roof extending outwardly from the stack above the fence, a louver at the opening between the fence and the roof for directing the air stream to the roof, and a circumferential baffle installed at the circumference of the bottom part of the stack. A preferable shape of the baffle is a truncated cone. Preferably, the stack has a fluidic diode, at the inside top thereof.

Abstract: A ground flare stack is described having a plurality of stages for combustion to accommodate various quantities of combustible waste gas, the stack having a dished base of gravel with a central combustion chamber with an enlarged opening at the bottom for entrance of air to support combustion, the central combustion chamber having an enlargement at its upper end with a converging discharge, a plurality of stages of combustion being provided within the chamber, the central combustion chamber being surrounded by a stack in spaced relation with a converging portion disposed around the combustion chamber enlargement and a cylindrical stack thereabove, with a diode to prevent downflow through the cylindrical stack, an acoustical and wind shielding fence being around the bottom of the stack permitting air to be supplied to the bottom of the stack and of the combustion chamber, additional stages of combustion being provided outwardly of the upper end of the central combustion chamber.