A staged-air burner for use in furnaces such as in steam cracking. The burner
includes
a burner tube including (i) a downstream end, (ii) an upstream end for receiving
fuel and air, flue gas or mixtures thereof from a primary air chamber, and (iii)
a burner tip mounted on the downstream end of said burner tube and directed to
the first flame opening in the furnace, so that combustion of the fuel takes place
downstream of said burner tip; a secondary air chamber for supplying a second portion
of combustion air, said secondary air chamber in fluid communication with at least
one air port; and a wall peripherally surrounding said burner tip to provide a
barrier between a base of a flame at said burner tip and said at least one air port.
