In accordance with the flow distribution of combustion gas including an unburned portion, an after-air port (AAP) arranged downstream of the two-stage combustion burner can effectively reduce the unburned portion by dividing as appropriate so as to avoid interaction, and by mixing together, two types of after-air having functions of linearity and spreading. As the configuration of this AAP, a primary nozzle for supplying primary after-air and having a vertical height greater than the horizontal width is provided in the center in the opening of the AAP, a secondary nozzle for supplying secondary after-air is provided in the opening outside of the primary nozzle, and one or more secondary after-air guide vanes having a fixed or variable tilt angle relative to the after-air port center axis are provided at the outlet of the said secondary nozzle to deflect and supply the secondary after-air horizontally to the left or right.

An apparatus for a fired heater is presented. The fired heater is designed with a plurality of process coils inside a shell, and with a positioning of the burners for reducing the size of the fired heater. The shell has a general rectangular prismatic shape with combustion inlets for admitting combustion gases from the burners, and the process coils include at least two inlet ports and at least one outlet port.

An apparatus for a fired heater is presented. The fired heater is designed with a plurality of process coils inside a shell, and with a positioning of the burners for reducing the size of the fired heater. The shell has a general rectangular prismatic shape with combustion inlets for admitting combustion gases from the burners, and the process coils include at least two inlet ports and at least one outlet port.

A regenerative burner including: a combustion chamber; a heat exchange chamber; and a communication passage therebetween, the combustion chamber includes a tip of a fuel nozzle and a flame ejection port, and is configured such that fuel introduced from the fuel nozzle into the combustion chamber can be burned in the combustion chamber using combustion air introduced into the combustion chamber through the communication passage to eject flame from the flame ejection port; the fuel nozzle is configured such that fuel burned in the regenerative burner is introduced into the combustion chamber; and the heat exchange chamber comprises a heat accumulator interposed between the communication passage and an air port, and is configured such that combustion air can pass through the heat accumulator and then be introduced into the combustion chamber such that an exhaust gas passes through the heat accumulator and is discharged from the air port.

An oxy-fuel burner including a central burner element having a central conduit terminating in a central nozzle and an annular conduit terminating in an annular nozzle surrounding the central conduit, the central conduit flowing a first reactant and the annular conduit flowing a second reactant; a first staging conduit spaced apart from a side of the central burner element and terminating in a first staging nozzle; a second staging conduit spaced apart from an opposite side the central burner element and terminating in a second staging nozzle; a first mechanism to apportion a flow of the second reactant into a non-zero primary flow of the second reactant directed to the annular conduit and a non-zero secondary flow of the second reactant; and a second mechanism to selectively apportion the secondary flow of the second reactant between the staging conduits; wherein one reactant is fuel and the other reactant is oxygen.

An oxy-fuel burner including a central burner element having a central conduit terminating in a central nozzle and an annular conduit terminating in an annular nozzle surrounding the central conduit, the central conduit flowing a first reactant and the annular conduit flowing a second reactant; a first staging conduit spaced apart from a side of the central burner element and terminating in a first staging nozzle; a second staging conduit spaced apart from an opposite side the central burner element and terminating in a second staging nozzle; a first mechanism to apportion a flow of the second reactant into a non-zero primary flow of the second reactant directed to the annular conduit and a non-zero secondary flow of the second reactant; and a second mechanism to selectively apportion the secondary flow of the second reactant between the staging conduits; wherein one reactant is fuel and the other reactant is oxygen.

A heater is provided which has a heating chamber divided into a plurality of heating compartments, each operably to provide heat in a respective heating direction. The heater includes a respective heating element for each heating compartment, and the operation of at least one of the heating elements is independently controllable from the operation of at least one other heating element. There is also provided a gas burner assembly the heat and a control system controlling the operation of the heating element.

A fired heater with a film temperature optimizer is presented. The fired heater is for heating a process fluid in process coils within the fired heater. The process coils experience high temperatures at the outlets. The film temperature optimizer includes baffles or means for changing the flow of the fired heating gas around the process coils near the coil outlets. The baffles are positioned near the process coil outlets.

An apparatus for a fired heater is presented. The fired heater is designed with a plurality of process coils inside a shell, and with a positioning of the burners for reducing the size of the fired heater. The shell has a general rectangular prismatic shape with combustion inlets for admitting combustion gases from the burners, and the process coils include at least two inlet ports and at least one outlet port.

A burner combustion method is employed in which at least two burners (2) are disposed opposite each other in a furnace (1) so as to cause combustion, the method comprising: cyclically changing at least one of a flow rate of a fuel fluid and a flow rate of an oxidant fluid supplied to the respective burners (2) while cyclically changing a concentration of oxygen in the oxidant fluid thereby cyclically changing an oxygen ratio obtained by dividing a supply oxygen amount by a theoretically required oxygen amount, whereby, the burners (2) are made to cause combustion in a cyclical oscillation state, wherein with respect to the cyclical change in an oscillation state of the burners (2), a phase difference is provided between a cyclical change in an oscillation state of at least one burner (2) and cyclical changes in oscillation states of other burners (2).