A boiler system is provided including: a boiler that burns fuel containing sulfur content, chlorine content, and water content to generate a combustion gas; a bagfilter that removes sulfur oxide; a denitration section that removes nitrogen oxide; a desulfurizing absorbent supply section that mixes a desulfurizing absorbent into the combustion gas on an upstream side of the bagfilter; and a reformer that mixes a denitrating reagent into the combustion gas on an upstream side of the denitration section, wherein the bagfilter performs dry desulfurization, and a temperature of the combustion gas passing through the bagfilter and flowing into the denitration section is higher than 200° C. and 350° C. or lower, and the combustion gas from which the sulfur oxide has been removed by the bagfilter flows into the denitration section without being heated on the upstream side of the denitration section.

A boiler system is provided including: a boiler that burns fuel containing sulfur content, chlorine content, and water content to generate a combustion gas; a bagfilter that removes sulfur oxide; a denitration section that removes nitrogen oxide; a desulfurizing absorbent supply section that mixes a desulfurizing absorbent into the combustion gas on an upstream side of the bagfilter; and a reformer that mixes a denitrating reagent into the combustion gas on an upstream side of the denitration section, wherein the bagfilter performs dry desulfurization, and a temperature of the combustion gas passing through the bagfilter and flowing into the denitration section is higher than 200° C. and 350° C. or lower, and the combustion gas from which the sulfur oxide has been removed by the bagfilter flows into the denitration section without being heated on the upstream side of the denitration section.

A heat exchanger tube block is stacked on another heat exchanger tube block in an upper-lower direction and connected to the another heat exchanger tube block. The heat exchanger tube block includes: a duct casing wherein exhaust gas containing dust flows in the upper-lower direction; a heat exchanger tube in the duct casing extends horizontally; an inlet header connects to the heat exchanger tube inlet; an outlet header connected to an outlet of the heat exchanger tube; and a vibration transmitting member transmitting vibration, applied to an upper end part of the vibration transmitting member, to the heat exchanger tube to make the dust accumulating on the heat exchanger tube fall. A lower end of the duct casing is formed horizontally. The inlet header is located higher than the lower end of the duct casing. The outlet header is located higher than the lower end of the duct casing.

A heat exchanger tube block is stacked on another heat exchanger tube block in an upper-lower direction and connected to the another heat exchanger tube block. The heat exchanger tube block includes: a duct casing wherein exhaust gas containing dust flows in the upper-lower direction; a heat exchanger tube in the duct casing extends horizontally; an inlet header connects to the heat exchanger tube inlet; an outlet header connected to an outlet of the heat exchanger tube; and a vibration transmitting member transmitting vibration, applied to an upper end part of the vibration transmitting member, to the heat exchanger tube to make the dust accumulating on the heat exchanger tube fall. A lower end of the duct casing is formed horizontally. The inlet header is located higher than the lower end of the duct casing. The outlet header is located higher than the lower end of the duct casing.

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 very low pressure steam stream may be employed as a first regeneration stream for the temperature swing adsorptive gas separator where the very low pressure steam stream may optionally be recovered from, a very low pressure steam turbine or an auxiliary boiler. 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 optionally be recovered from an electrostatic precipitator, an oxidant preheater, or 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 very low pressure steam stream may be employed as a first regeneration stream for the temperature swing adsorptive gas separator where the very low pressure steam stream may optionally be recovered from, a very low pressure steam turbine or an auxiliary boiler. 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 optionally be recovered from an electrostatic precipitator, an oxidant preheater, or an auxiliary heater.

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 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.