A flue pipe filter device for reducing nitrogen oxide (NOx) emission levels from gas fired appliances may include a flue cap with a pipe connection adapter sized to attach to an existing exhaust pipe; a fanned flue cap body with vents operatively attached to a distal end of the pipe connection adapter; and a filter positioned within the fanned flue cap body, the filter designed to convert NOx emissions into reduced NOx emissions. The filter may have an interior honeycomb structure.

Embodiments of the present disclosure include a system, method, and apparatus comprising a large scale direct steam generator operating on an oxidant of air or enriched air configured to generate steam and combustion exhaust constituents. An exhaust constituent separation system and an energy recovery system to reclaim energy and improve the efficiency of the thermodynamic cycle. An optional CO2 separation system and Non Condensable Gas injection system may be included.

An improved method and system for treating flue gases from a natural gas furnace are provided. The method and system include an acidic gas trap (AGT) adsorber which enables the continuous adsorption and storage of SOx, NOx redox, and formic acid/CO/HC/CH.sub.4 oxidation, with a negligible pressure drop. The AGT adsorber includes a catalyst coating having a nanotube structure (e.g., a uniform nanostructure forest coating) or a uniform porous nanostructure of various low-cost oxides through scalable low temperature solution processes, including oxides of Ti, Cu, Ba, Mn, Zr, Zn, Sr, Ca, Li, K, Na, Al, or Ce.

An improved method and system for treating flue gases from a natural gas furnace are provided. The method and system include an acidic gas trap (AGT) adsorber which enables the continuous adsorption and storage of SOx, NOx redox, and formic acid/CO/HC/CH.sub.4 oxidation, with a negligible pressure drop. The AGT adsorber includes a catalyst coating having a nanotube structure (e.g., a uniform nanostructure forest coating) or a uniform porous nanostructure of various low-cost oxides through scalable low temperature solution processes, including oxides of Ti, Cu, Ba, Mn, Zr, Zn, Sr, Ca, Li, K, Na, Al, or Ce.

The present disclosure is directed to the use of elemental or speciated iodine and bromine to control total mercury emissions.

The present disclosure is directed to the use of elemental or speciated iodine and bromine to control total mercury emissions.

A biomass heating system for burning fuel in the form of pellets and/or wood chips is disclosed, the system comprising the following: a boiler with a combustion device, a heat exchanger with a plurality of boiler tubes, wherein the combustion device comprises: a combustion chamber with a rotating grate, with a primary combustion zone and with a secondary combustion zone; wherein the primary combustion zone is enclosed by a plurality of combustion chamber bricks laterally and by the rotating grate from below; wherein a plurality of secondary air nozzles is provided in the combustion chamber bricks; wherein the primary combustion zone and the secondary combustion zone are separated at the level of the secondary air nozzles; wherein the secondary combustion zone of the combustion chamber is fluidically connected to an inlet of the heat exchanger.

The present disclosure is directed to the use of elemental or speciated iodine and bromine to control total mercury emissions.

The present disclosure is directed to the use of elemental or speciated iodine and bromine to control total mercury emissions.

A system is provided with a turbine combustor having a first diffusion fuel nozzle, wherein the first diffusion fuel nozzle is configured to produce a diffusion flame. The system includes a turbine driven by combustion products from the diffusion flame in the turbine combustor. The system also includes an exhaust gas compressor, wherein the exhaust gas compressor is configured to compress and route an exhaust gas from the turbine to the turbine combustor along an exhaust recirculation path. In addition, the system includes a control system configured to control flow rates of at least one oxidant and at least one fuel to the turbine combustor in a stoichiometric control mode and a non-stoichiometric control mode, wherein the stoichiometric control mode is configured to change the flow rates and provide a substantially stoichiometric ratio of the at least one fuel with the at least one oxidant, and the non-stoichiometric control mode is configured to change the flow rates and provide a non-stoichiometric ratio of the at least one fuel with the at least one oxidant.