A combustion system and process of operating the combustion system incorporating an electrostatic precipitator, an optional flue gas desulfurizer, and a temperature swing adsorptive gas separator, for post-combustion emission abatement is provided. A steam stream may be employed as a first regeneration stream for the temperature swing adsorptive gas separator. A fluid stream at a suitable temperature for regeneration of at least one adsorbent material in the temperature swing adsorptive gas separator may be employed as a second regeneration stream where the fluid stream may be recovered from an auxiliary heater.

A combustion system and process of operating the combustion system incorporating an electrostatic precipitator, an optional flue gas desulfurizer, and a temperature swing adsorptive gas separator, for post-combustion emission abatement is provided. A steam stream may be employed as a first regeneration stream for the temperature swing adsorptive gas separator. A fluid stream at a suitable temperature for regeneration of at least one adsorbent material in the temperature swing adsorptive gas separator may be employed as a second regeneration stream where the fluid stream may be recovered from an auxiliary heater.

The present invention provides an economizer 70 including a plurality of cylindrical heat transfer tubes 71a-71d extending along a crossing direction crossing a flowing direction of combustion gas and disposed at a predetermined disposition interval P along the flowing direction, the combustion gas and fluid flowing in the plurality of heat transfer tubes performing heat exchange, and a swirl preventing section 75 disposed in contact with a downstream side outer circumferential surface 71Aa-71Ad in the flowing direction of each of the plurality of heat transfer tubes 71a-71d and configured to prevent a swirl of the combustion gas from occurring near the downstream side outer circumferential surface 71Aa-71Ad.

A flash boiler has a water jacket and a vertically oriented interior passage which includes water tubes or superheating tubes, or both. The interior passage is a hyperboloid surface to induce draft. Water tubes and superheating tubes can be staggered so as to create a helical path for flue gas passing through the boiler. Water tubes and superheating tubes may include, internally or externally or both, heat transfer aids such as pins, fins or vanes, which may also be helices.

A flash boiler has a water jacket and a vertically oriented interior passage which includes water tubes or superheating tubes, or both. The interior passage is a hyperboloid surface to induce draft. Water tubes and superheating tubes can be staggered so as to create a helical path for flue gas passing through the boiler. Water tubes and superheating tubes may include, internally or externally or both, heat transfer aids such as pins, fins or vanes, which may also be helices.

A method of operating a furnace having a firing system is disclosed. The method includes providing a solid fuel to a sieve; separating the fuel into a portion and a second portion; providing a first portion of a flue gas to a first fuel dryer comprising a first duct; providing the first portion of fuel to the first duct, and drying the first portion of fuel therein; conveying the first portion of fuel through the first duct to the furnace; burning the first portion of fuel with firing system; conveying the second portion of fuel and a second portion of the flue gas to a second fuel dryer in a lower portion of the furnace, providing the second portion of fuel to a mill; pulverizing the second portion of fuel with the mill; conveying the second portion of fuel to the furnace; and burning the second portion of fuel.

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.

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.