A nuclear power plant comprising a primary coolant circuit, a steam-water circuit separated from the primary coolant circuit and a steam generator connected to the primary coolant circuit and the steam-water circuit to transfer heat from the primary coolant circuit into the steam-water circuit has at least one dosing point in the steam-water circuit to inject a reducing agent into the steam-water circuit, wherein the reducing agent is an organic compound consisting of carbon, hydrogen and oxygen. Furthermore, a method for operating said nuclear power plant and the use of the method for downtime preservation of the secondary side of a steam generator of a nuclear power plant are provided.

The present disclosure describes methods of controlling corrosion in aqueous heat transfer systems, such as boiler systems. The methods add a morpholine generating agent to the aqueous heat transfer system. The methods form morpholine in situ by the partial decomposition of the morpholine generating agent in the aqueous heat transfer system.

Disclosed is a heat exchange tube of waste heat boiler, which includes a tube body. The outer surface of the tube body is sprayed with a layer of anti-corrosion coating. The components of the anti-corrosion coating are Al.sub.2O.sub.3, CaAl.sub.2O.sub.4 and Ca.sub.3(PO.sub.4).sub.2. On the surface of nano anti-corrosion coating, HF reacts with Al.sub.2O.sub.3, CaAl.sub.2O.sub.4 and Ca.sub.3(PO.sub.4).sub.2 to form AlF.sub.3 and Ca.sub.5(PO.sub.4).sub.3F, which are tightly wrapped on the surface of the coating, thereby effectively preventing HF from corroding the interior of the coating and the heat exchange tube. Meanwhile, due to the anti-corrosion coating with the specific composition of the present disclosure, the heat exchange tube of the present disclosure can be resistant to fluorine corrosion at a high temperature of 600° C. or more, and can be used at a rather high temperature of 1000° C. or more.

In a seawater leakage detection device in a feedwater system, a method for detecting seawater leakage in a feedwater system, and a steam turbine plant, an ammonia addition device configured to add ammonia as a pH adjusting agent to feedwater at an upstream side of a high-pressure drum in a feedwater line, an acid electrical conductivity meter configured to measure an acid electrical conductivity of drum water in the high-pressure drum, and a control device configured to control the ammonia addition device such that a pH value of drum water in the heat recovery steam generator expresses alkalinity equal to or greater than a preset predetermined value, calculate a chlorine ion concentration of drum water on the basis of the acid electrical conductivity measured by the acid electrical conductivity meter, and determine whether leakage of seawater is detected are provided.

A system for producing steam includes a steam generator with steam output; a membrane filtration system in fluid communication with the steam output and including a membrane filter with a permeate side and an opposing retentate side. The membrane filter includes a separation membrane constructed to reject organic molecules. The system may be used for removing organic compounds, such as anti-corrosion agents or contaminants, from steam.

Disclosed is a heat exchange tube of waste heat boiler, which includes a tube body. The outer surface of the tube body is sprayed with a layer of anti-corrosion coating. The components of the anti-corrosion coating are Al.sub.2O.sub.3, CaAl.sub.2O.sub.4 and Ca.sub.3(PO.sub.4).sub.2. On the surface of nano anti-corrosion coating, HF reacts with Al.sub.2O.sub.3, CaAl.sub.2O.sub.4 and Ca.sub.3(PO.sub.4).sub.2 to form AlF.sub.3 and Ca.sub.5(PO.sub.4).sub.3F, which are tightly wrapped on the surface of the coating, thereby effectively preventing HF from corroding the interior of the coating and the heat exchange tube. Meanwhile, due to the anti-corrosion coating with the specific composition of the present disclosure, the heat exchange tube of the present disclosure can be resistant to fluorine corrosion at a high temperature of 600° C. or more, and can be used at a rather high temperature of 1000° C. or more.

A method for improving effectiveness of a steam generator system includes providing a steam generator system including a steam generator vessel, an air supply system and an air preheater. The air supply system is in communication with the steam generator vessel through the air preheater and the steam generator vessel is in communication with the air preheater. The air supply system provides a first amount of air to the air preheater. At least a portion of the first amount of air is provided to the steam generator vessel. A flue gas mixture is discharged from the steam generator vessel. At least a portion of the flue gas mixture flows into the air preheater. SO.sub.3 in the flue gas mixture is mitigated before the flue gas mixture enters the air preheater.

A system for producing steam includes a steam generator with steam output; a membrane filtration system in fluid communication with the steam output and including a membrane filter with a permeate side and an opposing retentate side. The membrane filter includes a separation membrane constructed to reject organic molecules. The system may be used for removing organic compounds, such as anti-corrosion agents or contaminants, from steam.

A combined cycle power plant and a method for operating a combined cycle power plant are presented. The combined cycle power plant includes a condensate recirculation pump to recirculate flow medium from downstream of a condensate preheater system to upstream of the condensate preheater system. An adequate flow temperature at the upstream of the condensate preheater system may be maintained to prevent acid gas dew point corrosion. The condensate recirculation pump may use a venturi effect to convert a high pressure of a condensate supplied by a condensate extraction pump to a suction pressure for the recirculation.

A method for improving effectiveness of a steam generator system includes providing air to an air preheater at a mass flow such that the air preheater has a cold end outlet temperature defined by the improved air preheater operating with increased heat recovery (HR) of at least 1% calculated according to the equation: HR=100%((TgiTgoAdvX)/(TgiTgoSTD)1). The method requires either reducing the amount of heat that flows into the air preheater from the flue gas and/or increasing the amount of heat extracted from the flue gas. The method includes mitigating SO.sub.3 in the flue gas which is discharged directly from the air preheater to a particulate removal system and then directly into a flue gas desulfurization system. The method includes extracting heat from the Flue gas to create equipment preheat and/or flue gas stack reheat air with the latter being fed to heat the flue gas prior to entering a discharge stack to raise the temperature of the flue gas to mitigate visible plume exiting and to mitigate corrosion in, the discharge stack.