A wet desulfurization apparatus which removes sulfur oxides in flue gas from a boiler 11 includes a mist collection/agglomeration apparatus which is provided on a downstream side of the desulfurization apparatus and forms agglomerated SO.sub.3 mist by causing particles of SO.sub.3 mist contained in flue gas 12B from the wet desulfurization apparatus to be bonded together and have bloated particle sizes; a CO.sub.2 recovery apparatus constituted by a CO.sub.2 absorption tower having a CO.sub.2 absorption unit which removes CO.sub.2 contained in flue gas by being brought into contact with a CO.sub.2 absorbent and an absorbent regeneration tower which recovers CO.sub.2 by releasing CO.sub.2 from the CO.sub.2 absorbent having absorbed CO.sub.2 and regenerates the CO.sub.2 absorbent; and a mist collection unit which collects CO.sub.2 absorbent bloated mist bloated by the CO.sub.2 absorbent being absorbed by the agglomerated SO.sub.3 mist in the CO.sub.2 absorption unit.

A method for isolating substantially pure carbon dioxide from flue gas is provided. The method can include combusting carbon based fuel to form flue gas; cooling the flue gas to provide substantially dry flue gas; removing N.sub.2 from the dry flue gas to provide substantially N.sub.2 free flue gas CO.sub.2; and liquifying the substantially N.sub.2 free flue gas CO.sub.2 to form substantially pure carbon dioxide.

A CO2 capture system includes an intake for CO2-rich exhaust gas to a compressor and one or more outlets for compressed, first CO2-rich gas to a manifold to a shell enclosing parts of a combustion chamber. The combustion chamber has burners to burn fuel and compressed air from a fuel line and an air supply pipe, to form a second, CO2 rich gas.

The wall in the combustion chamber has slits to let in the compressed CO2-rich gas to mix with and cool the other CO2-rich gas formed in the combustion chamber of a third CO2-rich exhaust gas. A heat exchanger operates under high pressure and heat exchanges the third, hot CO2-rich exhaust gas from the combustion chamber with returning CO2-poor exhaust gas from a CO2 extraction plant. The returned, heated CO2-poor exhaust gas is led back to an expander driving the compressor and the CO2 extraction plant.

Sorbent components containing halogen, calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents such as calcium bromide are added to the coal ahead of combustion and other components are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

A thermal power plant exhaust purification device, the device including a cooling substance flow channel and an exhaust flow channel; the device also includes a spacing member for spacing and exchanging heat between the cooling substance flow channel and the exhaust flow channel, the spacing member having an exhaust contact surface for collecting dust and/or mist contained in the exhaust; the cooling substance flows in the cooling substance flow channel, such that the condensate precipitated from hot exhaust uniformly adheres on the exhaust contact surface, thus forming a uniform and stable water film; on one hand, formation of the concentrated H.sub.2SO.sub.4 on a dust collecting plate is prevented, and a liquid film flows downwards under gravity, thereby cleaning the H.sub.2SO.sub.4 adhered on the dust collecting plate timely; on the other hand, the water film is very effective in intercepting droplets and capturing the dust.

A thermal power plant exhaust purification device, the device including a cooling substance flow channel and an exhaust flow channel; the device also includes a spacing member for spacing and exchanging heat between the cooling substance flow channel and the exhaust flow channel, the spacing member having an exhaust contact surface for collecting dust and/or mist contained in the exhaust; the cooling substance flows in the cooling substance flow channel, such that the condensate precipitated from hot exhaust uniformly adheres on the exhaust contact surface, thus forming a uniform and stable water film; on one hand, formation of the concentrated H.sub.2SO.sub.4 on a dust collecting plate is prevented, and a liquid film flows downwards under gravity, thereby cleaning the H.sub.2SO.sub.4 adhered on the dust collecting plate timely; on the other hand, the water film is very effective in intercepting droplets and capturing the dust.

Boiler systems and associated control systems, methods for operating same, are described herein. In one example embodiment, a boiler system includes a furnace, an exhaust passage, an air passage, a FGR passage, a flue gas valve that is adjustable by way of a first actuator, a NO.sub.X gas sensor, an oxygen gas sensor, and an additional valve that is adjustable by way of a second actuator. Further, the boiler system includes at least one processing device coupled to the NO.sub.X gas sensor, the oxygen gas sensor, the first actuator and the second actuator. The at least one processing device is configured to generate control signals that are provided to the first actuator and second actuator, and also configured to generate correction factors by way of a calibration process and to utilize one or more of the correction factors in determining one or more of the control signals.

Boiler systems and associated control systems, methods for operating same, are described herein. In one example embodiment, a boiler system includes a furnace, an exhaust passage, an air passage, a FGR passage, a flue gas valve that is adjustable by way of a first actuator, a NO.sub.X gas sensor, an oxygen gas sensor, and an additional valve that is adjustable by way of a second actuator. Further, the boiler system includes at least one processing device coupled to the NO.sub.X gas sensor, the oxygen gas sensor, the first actuator and the second actuator. The at least one processing device is configured to generate control signals that are provided to the first actuator and second actuator, and also configured to generate correction factors by way of a calibration process and to utilize one or more of the correction factors in determining one or more of the control signals.

A method for the control of nitrogen oxides content in the combustion fumes of a thermal power plant is disclosed; the method comprises the on-site production of ammonia by the steps of: electrolysis of water as a source of hydrogen; separation of air as a source of nitrogen, formation of a make-up gas and synthesis of ammonia in a suitable synthesis loop; said on-site produced ammonia, or a solution thereof, is used for a process of reduction of nitrogen oxides in the combustion fumes.

A combustion-support-gas bypass line is provided to cause combustion support gas to bypass a preheater. A combustion-support-gas flow control damper is provided in the combustion-support-gas bypass line. An inlet temperature of a deduster is measured by a temperature sensor and the inlet temperature measured by the temperature sensor is inputted to a controller and is compared with a set temperature more than an acid dew-point preliminarily set in the controller. On the basis of a comparison result, an opening-degree control signal is outputted from the controller to the combustion-support-gas flow control damper so as to make the inlet temperature to a set temperature more than an acid dew-point.