A combustion system such as a furnace or boiler includes a perforated reaction holder configured to hold a combustion reaction that produces very low oxides of nitrogen (NOx).

Combustion systems and associated methods are disclosed herein. In some embodiments, a combustion system comprises a first combustion zone, a second combustion zone downstream of the first combustion zone, and a heat module thermally coupled to the first combustion zone and/or second combustion zone. The first combustion zone is configured to (i) receive and combust preheated air and a first fuel and (ii) generate a first exhaust gas, and the second combustion zone is configured to (i) receive and combust the first exhaust gas and a second fuel and (ii) generate a second exhaust gas. The first exhaust gas can have a first excess air and the second exhaust gas can have a second excess air less than the first excess air. The heat module can comprise a thermionic converter or another heat-to-electricity converter able to generate a power output.

A process plant and a process for production of sulfur from a feedstock gas including from 15% to 100 vol % H.sub.2S and a stream of sulfuric acid, the process including a) providing a Claus reaction furnace feed stream with a substoichiometric amount of oxygen, b) directing to a Claus reaction furnace operating at elevated temperature, c) cooling to provide a cooled Claus converter feed gas, d) directing to contact a material catalytically active in the Claus reaction, e) withdrawing a Claus tail gas and elementary sulfur, f) directing a stream comprising said Claus tail gas to a Claus tail gas treatment, wherein sulfuric acid directed to said Claus reaction furnace is in the form of droplets with 90% of the mass of the droplets having a diameter below 500 μm, with the associated benefit of such a process efficiently converting all liquid H.sub.2SO.sub.4 to gaseous H.sub.2SO.sub.4 and further to SO.sub.2.

A method and device heat an object to be heated by a flame which is produced by supplying a fuel fluid and a combustion supporting gas to a burner as a heat, source. A temperature rising rate is increased by gradually increasing an oxygen concentration in the combustion supporting gas supplied to the burner and a device for heating an object to be heated including a burner for heating the object to be heated. A flow rate control unit controls a flow rate of a fuel fluid and a combustion supporting gas. A calculation unit transmits combustion information of the burner to the flow rate control unit, and the flow rate control unit increases a temperature rising rate of the object to be heated by increasing the oxygen concentration in the combustion supporting gas supplied to the burner.

A revamp process for modifying a sulfur abatement plant including a Claus process plant, the Claus process plant including a Claus reaction furnace and one or more Claus conversion stages, each Claus conversion stage including a conversion reactor and a means for elemental sulfur condensation, and a means of Claus tail gas oxidation configured for receiving a Claus tail gas from said Claus process plant and configured for providing an oxidized Claus tail gas, the process revamp including: a) providing a sulfuric acid producing tail gas treatment plant producing sulfuric acid, and b) providing a means for transferring an amount or all of the sulfuric acid produced in said sulfuric acid producing tail gas treatment plant to said Claus reaction furnace, wherein the moles of sulfur in the transferred sulfuric acid relative to the moles of elemental sulfur withdrawn from the Claus process plant is from 3% to 25%.

Combined combustion and post-combustion method whereby flue gas is generated by combustion in a main combustion zone, the flue gas being evacuated from the main combustion zone and introduced into a post-combustion zone where the flue gas is subjected to post-combustion and post-combusted gas is obtained which is evacuated from the post-combustion zone, whereby a first level of one or more combustible substances in the flue gas evacuated from the main combustion zone and/or a second level of one or more combustible substances in the post-combusted gas evacuated from the post-combustion zone is/are monitored, whereby a control signal is generated on the basis of the monitored level(s) and whereby the post-combustion oxidant injection rate or the stoichiometric excess of post-combustion-oxidant with respect to post-combustion fuel is regulated in function of said control signal.

A method is disclosed for controlling fuel injection in a reheat combustor of a gas turbine combustor assembly including a combustor casing defining a gas flow channel and a plurality of injection nozzles distributed in or around the gas flow channel; the method includes the step of distributing fuel among the injection nozzles according to a non-uniform distribution pattern.

An improved chemical looping combustion (CLC) process and system includes a hopper containing oxygen carrier particles, e.g., metal oxides, that are gravity fed at a controlled rate of flow from the hopper into (a) a generally vertical downflow reactor where they are mixed with all of the hydrocarbon fuel feed to the system and (b) into one or more standpipes that are in communication with a plurality of staged fluidized reactor beds, the amount of the oxygen carrier particles introduced into the system being stoichiometrically predetermined to produce a syngas mixture of H.sub.2 and CO.sub.2; or to complete combustion of the fuel to CO.sub.2 and water vapor, thereby permitting capture of a majority of the CO.sub.2 produced in an essentially pure form.

Embodiments of the present invention include high-temperature staged recirculating burners and radiant tube burner assemblies that provide high efficiency, low NOx and CO emissions, and uniform temperature characteristics. One such staged recirculating burner includes a combustion tube having inside and outside helical fins forming opposing spiral pathways for combustion gases and products of combustion, a combustion nozzle coupled to the combustion tube, a gas tube running axially into the combustion tube, and a staging gas nozzle coupled to the gas tube, where the staging gas nozzle includes radial exit holes into the combustion tube and an axial gas staging tube extending into the combustion nozzle to stage combustion.

A process plant and a process for production of sulfur from a feedstock gas including from 15% to 100 vol % H.sub.2S and a stream of sulfuric acid, the process including a) providing a Claus reaction furnace feed stream with a substoichiometric amount of oxygen, b) directing to a Claus reaction furnace operating at elevated temperature, c) cooling to provide a cooled Claus converter feed gas, d) directing to contact a material catalytically active in the Claus reaction, e) withdrawing a Claus tail gas and elementary sulfur, f) directing a stream comprising said Claus tail gas to a Claus tail gas treatment, wherein sulfuric acid directed to said Claus reaction furnace is in the form of droplets with 90% of the mass of the droplets having a diameter below 500 μm, with the associated benefit of such a process efficiently converting all liquid H.sub.2SO.sub.4 to gaseous H.sub.2SO.sub.4 and further to SO.sub.2.