Methods and combustion devices for reducing NOx formation upon combusting oxidant with fuel to form products of combustion are provided. Such methods and device may involve mixing at least first portions of at least two fluids selected from the group of oxidant, fuel and recirculated products of combustion in at least one first conduit to form a first mixture. The first mixture is subsequently supplied to a plurality of second conduits each in direct fluid communication with the first conduit. Motive energy is utilized to aspirate at least second portions of one or more fluids selected from the group of oxidant, fuel and recirculated products of combustion in at least one second conduit to form a combustible mixture that can be subsequently burned. In one embodiment, the motive energy may be provided or result from the first mixture.

A furnace including a combustion chamber for burning fuel can have increased fuel burning efficiency, increased heating efficiency, and decreased harmful emissions of combustion byproducts. A combustion air delivery system delivers primary and secondary combustion air to the combustion chamber. Primary and secondary combustion air may be delivered at amounts that increase burning efficiency. An amount of secondary combustion air can be controlled by a valve system. A heat transfer device efficiently transfers heat from products of combustion for heating an enclosed space.

The present disclosure provides for improving flame propagation in a combustor, particularly in a combustor for use in a power production system and method. At least one stream being passed into the combustor (e.g., a fuel, an oxidant, a diluent, a coolant, a working fluid, water, or steam) can be independently heated to a temperature that is about the autoignition temperature of the fuel or greater. Further, flame stabilization, including promoting ignition, can be improved as described herein through controlled addition of one or more NOx species into the combustor or combustion chamber.

The present disclosure provides for improving flame propagation in a combustor, particularly in a combustor for use in a power production system and method. At least one stream being passed into the combustor (e.g., a fuel, an oxidant, a diluent, a coolant, a working fluid, water, or steam) can be independently heated to a temperature that is about the autoignition temperature of the fuel or greater. Further, flame stabilization, including promoting ignition, can be improved as described herein through controlled addition of one or more NOx species into the combustor or combustion chamber.

At a center portion of a ceiling wall of a furnace body having a lateral wall between the ceiling wall and a bottom wall, there is a burner that combusts downwards. A reforming reaction tube is provided in a circumference of the burner to carry out a steam reforming treatment on a source gas. A discharging portion is an opening at an upper side portion of the lateral wall for discharging combustion gas of the burner. A cylindrical outer wall is disposed at an outer side portion of the lateral wall. In an outside space formed between the lateral wall and the outer wall, there is a steam generating heat exchanger generating steam or a mixture gas of a source gas and steam. At a lower side portion of the outer wall, there is outside discharging opening discharging the combustion gas which flows through the outside space.

At a center portion of a ceiling wall of a furnace body having a lateral wall between the ceiling wall and a bottom wall, there is a burner that combusts downwards. A reforming reaction tube is provided in a circumference of the burner to carry out a steam reforming treatment on a source gas. A discharging portion is an opening at an upper side portion of the lateral wall for discharging combustion gas of the burner. A cylindrical outer wall is disposed at an outer side portion of the lateral wall. In an outside space formed between the lateral wall and the outer wall, there is a steam generating heat exchanger generating steam or a mixture gas of a source gas and steam. At a lower side portion of the outer wall, there is outside discharging opening discharging the combustion gas which flows through the outside space.

A plurality of independently flow rate-controlled flows of oxidant may be preheated at a heat exchanger (or both oxidant and fuel at separate heat exchangers) by heat exchange with a hot shell-side (heat transfer) fluid. The separate flows of hot oxidant are directed to associated separate burners where they combust with flows of fuel to produce hot combustion gases. The hot combustion gases are used to preheat the hot shell-side fluid at a recuperator or regenerator.

A plurality of independently flow rate-controlled flows of oxidant may be preheated at a heat exchanger (or both oxidant and fuel at separate heat exchangers) by heat exchange with a hot shell-side (heat transfer) fluid. The separate flows of hot oxidant are directed to associated separate burners where they combust with flows of fuel to produce hot combustion gases. The hot combustion gases are used to preheat the hot shell-side fluid at a recuperator or regenerator.

The present invention relates to a combustion apparatus capable of reducing the combustion load of a burner and improving the combustion efficiency thereof. The combustion apparatus includes: a premixing chamber for premixing external air, introduced through an air supply inlet, with a combustion gas; a blower for supplying a mixed air premixed in the premixing chamber toward a burner; a combustion chamber for burning the mixed air by ignition of the burner; a heat exchanger for heat exchange with room heating water by using the combustion heat of the combustion chamber; an exhaust gas discharging part for discharging an exhaust gas having passed through the heat exchanger; and a duct through which the exhaust gas having passed through the exhaust gas discharging part is discharged outside, wherein the combustion apparatus includes an air intake preheater for heat exchange between the exhaust gas discharged to the duct through the exhaust gas discharging part and the air supplied to the premixing chamber through the air supply inlet, the air intake preheater including a channel-forming member in which a plurality of unit plates are stacked with a predetermined interval therebetween to form an exhaust gas channel and an air intake channel therein that are separated from each other, are adjacent to each other, and are alternately arranged.

The present invention relates to a combustion apparatus capable of reducing the combustion load of a burner and improving the combustion efficiency thereof. The combustion apparatus includes: a premixing chamber for premixing external air, introduced through an air supply inlet, with a combustion gas; a blower for supplying a mixed air premixed in the premixing chamber toward a burner; a combustion chamber for burning the mixed air by ignition of the burner; a heat exchanger for heat exchange with room heating water by using the combustion heat of the combustion chamber; an exhaust gas discharging part for discharging an exhaust gas having passed through the heat exchanger; and a duct through which the exhaust gas having passed through the exhaust gas discharging part is discharged outside, wherein the combustion apparatus includes an air intake preheater for heat exchange between the exhaust gas discharged to the duct through the exhaust gas discharging part and the air supplied to the premixing chamber through the air supply inlet, the air intake preheater including a channel-forming member in which a plurality of unit plates are stacked with a predetermined interval therebetween to form an exhaust gas channel and an air intake channel therein that are separated from each other, are adjacent to each other, and are alternately arranged.