A power generating system includes a condensing steam turbine fed with steam from a boiler, wherein the air supply for the boiler combustion process is preheated by means of a heat pump system comprising at least one heat pump with at least one compressor, before entry to the boiler. A method for generating power using the power generating system is also described. A method and apparatus for extracting heat from the gases of a combustion process are also described.

A power generating system includes a condensing steam turbine fed with steam from a boiler, wherein the air supply for the boiler combustion process is preheated by means of a heat pump system comprising at least one heat pump with at least one compressor, before entry to the boiler. A method for generating power using the power generating system is also described. A method and apparatus for extracting heat from the gases of a combustion process are also described.

Aqueous working fluid (WF) steam generation system including: pressure vessel containing heat exchanger; enclosed combustion air (CA) chamber; burner; another heat exchanger outside pressure vessel; and WF conduit. Heat exchanger includes first: enclosed WF chamber having WF input and output apertures (IOA); and enclosed CA passageway communicating with CAIOA and passing through enclosed WF chamber. Enclosed CA chamber includes second: enclosed WF chamber having WFIOA; and enclosed CA passageway communicating with CAIOA. Burner is connected to second CA input aperture. Another heat exchanger includes third: enclosed WF chamber having WFIOA; and enclosed CA passageway communicating with CAIOA. WF conduit connects third WF output aperture to second WF input aperture. Second WF output aperture is connected to first WF input aperture; and second CA output aperture is connected to first CA input aperture; and first CA output aperture is connected to third CA input aperture.

Aqueous working fluid (WF) steam generation system including: pressure vessel containing heat exchanger; enclosed combustion air (CA) chamber; burner; another heat exchanger outside pressure vessel; and WF conduit. Heat exchanger includes first: enclosed WF chamber having WF input and output apertures (IOA); and enclosed CA passageway communicating with CAIOA and passing through enclosed WF chamber. Enclosed CA chamber includes second: enclosed WF chamber having WFIOA; and enclosed CA passageway communicating with CAIOA. Burner is connected to second CA input aperture. Another heat exchanger includes third: enclosed WF chamber having WFIOA; and enclosed CA passageway communicating with CAIOA. WF conduit connects third WF output aperture to second WF input aperture. Second WF output aperture is connected to first WF input aperture; and second CA output aperture is connected to first CA input aperture; and first CA output aperture is connected to third CA input aperture.

In a clean boiler with steam conversion and hydrogen/oxygen pre-blending, the clean boiler comprises two identical boiler bodies integrated to form a single entity. The clean boiler comprises two slim cavities, four water-containing chambers and four combustors, which is heated at wide faces and generates steams rapidly. The boiler comprises an integrate body containing two independent boiler bodies (1), and each of the independent boiler bodies (1) contains an independent boiler chamber (19). A steam conversion and transformation system is simultaneously provided for introducing a part of steam into the independent boiler chamber (19). High temperature of the boiler chamber (19) is utilized to promote a decomposition of the steam into H.sub.2 and O.sub.2. Water formed by H.sub.2 and O.sub.2 is utilized as a fuel to provide a self-sustaining combustion and heating, thus reducing a dependence on a primary energy source, reducing carbon emissions and protecting the environment.

A gas-fired atmospheric pressure steam humidifier having high efficiency and ultra-low NOx(3) emissions is disclosed. In some examples, the gas-fired humidifier can have an efficiency of greater than 90 percent and a NOx(3) output of less than 20 parts per million (ppm). In one aspect, the humidifier includes a secondary heat exchanger having a first heat exchange section for pre-heating combustion air and a separate second heat exchange section for pre-heating make-up water, wherein the first and second heat exchange sections are in heat transfer communication with exhaust gases generated by the gas-fired burner and combustion blower assembly. In some examples, the first heat exchange section includes orifices for enabling flue gas recirculation.

A gas-fired atmospheric pressure steam humidifier having high efficiency and ultra-low NOx(3) emissions is disclosed. In some examples, the gas-fired humidifier can have an efficiency of greater than 90 percent and a NOx(3) output of less than 20 parts per million (ppm). In one aspect, the humidifier includes a secondary heat exchanger having a first heat exchange section for pre-heating combustion air and a separate second heat exchange section for pre-heating make-up water, wherein the first and second heat exchange sections are in heat transfer communication with exhaust gases generated by the gas-fired burner and combustion blower assembly. In some examples, the first heat exchange section includes orifices for enabling flue gas recirculation.

A heat transfer element comprising an inlet, an outlet, vertical heat exchanger tubes, a lower collector and an upper distributor. A vertical riser pipe is arranged between the inlet and the upper distributor. This minimizes thermal stress in the heat exchanger element in the application.

A heat transfer element comprising an inlet, an outlet, vertical heat exchanger tubes, a lower collector and an upper distributor. A vertical riser pipe is arranged between the inlet and the upper distributor. This minimizes thermal stress in the heat exchanger element in the application.

A device with a heat exchanger with a feed pipe for a medium leading from a medium inlet to the heat exchanger entrance and with a discharge pipe leading away from the heat exchanger exit is characterized in that it has a first bypass from the medium inlet to the discharge pipe and a second bypass from the feed pipe to the medium outlet and valves, so that the medium can also flow from the heat exchanger exit to the heat exchanger entrance.