A burner sub-system, a furnace comprising the same, a fuel combustion process and steam cracking process carried out in the furnace. The burner sub-system comprises a barrier wall segment between the burner tip and the flue-gas recirculation (FGR) duct, effectively blocking direct gas flow between the burner tip and the FGR duct opening, but without encircling the whole burner tip. The presence of the partial barrier wall has the advantage of preventing the temperature inside the FGR duct from becoming too high, while achieving low NOx emissions from the combustion process without overheating the burner tip because of reduced amount of heat reflection to the burner tip compared to an annular barrier wall. The invention is particularly useful in furnaces where hydrogen-rich fuel gas is combusted.

A burner including a first pulverized coal entrained fluid flow conduit; an inner hydrogen conduit; and a hydrogen oxidant conduit positioned between the first pulverized coal entrained fluid flow conduit and the inner hydrogen conduit; an outlet of the inner hydrogen conduit positioned a first distance from an outlet of the hydrogen oxidant conduit such that hydrogen output from the outlet of the inner hydrogen conduit passes through a portion of the hydrogen oxidant conduit to the outlet of the hydrogen oxidant conduit; and the outlet of the hydrogen oxidant conduit being a second distance from an outlet of the first pulverized coal entrained fluid flow conduit such that the hydrogen and the hydrogen oxidant output from the outlet of the hydrogen oxidant conduit passes through a portion of the first pulverized coal entrained fluid flow conduit for being output from the burner.

A fuel-fired burner includes a combustion air inlet for receiving combustion air coupled to a combustion air nozzle at an input to a second chamber within a burner housing spaced apart from a third chamber within the second chamber. The combustion air nozzle directs the combustion air into the third chamber. A fuel inlet coupled to a burner nozzle secured to a burner mounting plate has a recycle port for receiving hot exhaust gas provided to an exhaust gas path. A jet pump located entirely inside the burner housing is configured to receive the hot exhaust gas from the exhaust gas path. The jet pump operates by flowing the combustion air through the combustion air nozzle which suctions in the hot exhaust gas through the recycle port into the exhaust gas path then into a gas mixing zone for mixing the hot exhaust gas and the combustion air.

A combustor includes a combustion tube having a cylindrical shape with a combustion space where fuel is combusted and including an inlet through which the fuel is introduced, an outlet through which a gas generated when the fuel is combusted is discharged, and a protrusion protruding inward from a wall surface between the inlet and the outlet; an injection unit configured to inject fuel into the combustion tube through the inlet of the combustion tube; and an additional injection unit located on the protrusion of the combustion tube and configured to inject fuel into the combustion tube.

A combustion system includes a fuel distributor configured to output a fuel, an oxidant source configured to output an oxidant, and a mixing tube defining a mixing volume aligned to receive the fuel and oxidant. The mixing tube is shaped to convey the fuel and the oxidant through the mixing volume at a bulk velocity higher than a flame propagation speed. The combustion system includes a flame holder aligned to receive the mixed fuel and oxidant and to support a combustion reaction of the fuel and the oxidant.

A combustion system includes a fuel distributor configured to output a fuel, an oxidant source configured to output an oxidant, and a mixing tube defining a mixing volume aligned to receive the fuel and oxidant. The mixing tube is shaped to convey the fuel and the oxidant through the mixing volume at a bulk velocity higher than a flame propagation speed. The combustion system includes a flame holder aligned to receive the mixed fuel and oxidant and to support a combustion reaction of the fuel and the oxidant.

A ground supported single drum power boiler is described combining a refractory lined and insulated V-Cell floor; refractory lined and insulated combustion chamber; integrated fuel chutes configured to pre-dry wet solid fuel; top mounted fuel bin; internal chamber walls; configurable combustion air systems; and a back pass with after-burner ports and cross flow superheaters. The boiler can be configured in pre-assembled modules to minimize the field construction time and cost. An alternative embodiment is adaptable as a gasifier.

A ground supported single drum power boiler is described combining a refractory lined and insulated V-Cell floor; refractory lined and insulated combustion chamber; integrated fuel chutes configured to pre-dry wet solid fuel; top mounted fuel bin; internal chamber walls; configurable combustion air systems; and a back pass with after-burner ports and cross flow superheaters. The boiler can be configured in pre-assembled modules to minimize the field construction time and cost. An alternative embodiment is adaptable as a gasifier.

A burner sub-system, a furnace comprising the same, a fuel combustion process and steam cracking process carried out in the furnace. The burner sub-system comprises a barrier wall segment between the burner tip and the flue-gas recirculation (FGR) duct, effectively blocking direct gas flow between the burner tip and the FGR duct opening, but without encircling the whole burner tip. The presence of the partial barrier wall has the advantage of preventing the temperature inside the FGR duct from becoming too high, while achieving low NOx emissions from the combustion process without overheating the burner tip because of reduced amount of heat reflection to the burner tip compared to an annular barrier wall. The invention is particularly useful in furnaces where hydrogen-rich fuel gas is combusted.

A flue gas recirculation combustor includes a combustor chamber configured such that fuel and combustion gas are injected therein to cause combustion and having a nozzle-side end and a combustor outlet, a nozzle can connected to the nozzle-side end of the combustor chamber, a plurality of nozzles disposed in the nozzle can and configured such that an injection direction thereof is directed to a side of the combustor chamber, and a sleeve disposed in a premixing space defined between the nozzle can and the nozzle-side end of the combustor chamber, the sleeve including a recirculation pathway to recirculate combustion air from the combustor chamber to the premixing space.