Abstract: A method for decontaminating the nickel-based alloy includes oxidization of an oxide film accumulating radioactive nuclides with a first oxidizing agent to elute nickel into a solvent and thus to transform into a low-nickel film (S13 to S15). Elution amounts of Nickel, Chromium, and iron in the solvent are measured in the step S15 of the first oxidation step. Based on the elution amount, a second oxidizing agent is selected in the step S16. With the second oxidizing agent, the low-nickel film is oxidized to elute Chromium and thus to transform into an iron-concentrated film (S17 to S19). The iron-concentrated film is reduced with a reducing agent after the second oxidizing step including the steps of S13 to S19 to be dissolved and thus to be removed (S22).

Abstract: A chemical solution injection system 30 of an embodiment includes: a chemical solution reservoir 31 that stores a chemical solution containing a depositing substance to deposit to a member in contact with cooling water for absorbing heat in a plant; a pipe 32 through which the chemical solution passes; a first heat exchanger and a second heat exchanger that exchange heat between the cooling water and the chemical solution; a cooling water pipe 49 which connects the heat exchangers in series and in which the cooling water passes; and a pump 34 that conveys the chemical solution. The temperature of the chemical solution in the chemical solution reservoir 31 is lower than that of the cooling water. The pipe 32 sequentially connects the chemical solution reservoir 31, the first heat exchanger, the second heat exchanger and the plant. The cooling water guided from the inside of the plant passes through the second heat exchanger and subsequently passes through the first heat exchanger.

Abstract: The present invention provides a corrosion-resistant structure for a high-temperature water system comprising: a structural material 1; and a corrosion-resistant film 3 formed from a substance containing at least one of La and Y deposited on a surface in a side that comes in contact with a cooling water 4, of the structural material 1 which constitutes the high-temperature water system that passes a cooling water 4 of high temperature therein. Due to above construction, there can be provided the corrosion-resistant structure and a corrosion-preventing method capable of operating a plant without conducting a water chemistry control of cooling water by injecting chemicals.

Abstract: A straightening device for welding wire is provided with two sets of roll groups, having a plurality of straightening rolls with which bends in a welding wire are straightened by passing the welding wire through the two sets of roll groups. The plurality of straightening rolls configuring the roll groups, are arranged at a predetermined arrangement interval along a passing direction of the welding wire in such a way as to face with each other across a straightening path along which the welding wire passes, and the two sets of roll groups, are arranged so that the directions in which they face across the straightening path are different from each other. By configuring the straightening rolls by small-diameter rollers, adverse effects on the welding wire are suppressed, and the welding wire is straightened finely.

Abstract: A photocatalyst injection system including: a reactor primary system coolant collection section collecting a reactor primary system coolant containing a noble metal or noble metal ion from a reactor primary system; a photocatalyst addition section adding a photocatalyst to the collected reactor primary system coolant; an ultraviolet irradiation section irradiating, with ultraviolet rays, the coolant to which the photocatalyst has been added for producing, in the coolant, a noble metal-carrying photocatalyst in which the noble metal is carried on a surface of the photocatalyst; and a noble metal-carrying photocatalyst injection section injecting the coolant containing the noble metal-carrying photocatalyst into the reactor primary system.

Abstract: The present invention provides a corrosion-resistant structure for a high-temperature water system comprising: a structural material 1; and a corrosion-resistant film 3 formed from a substance containing at least one of La and Y deposited on a surface in a side that comes in contact with a cooling water 4, of the structural material 1 which constitutes the high-temperature water system that passes a cooling water 4 of high temperature therein. Due to above construction, there can be provided the corrosion-resistant structure and a corrosion-preventing method capable of operating a plant without conducting a water chemistry control of cooling water by injecting chemicals.

Abstract: A chemical solution injection system 30 of an embodiment includes: a chemical solution reservoir 31 that stores a chemical solution containing a depositing substance to deposit to a member in contact with cooling water for absorbing heat in a plant; a pipe 32 through which the chemical solution passes; a first heat exchanger and a second heat exchanger that exchange heat between the cooling water and the chemical solution; a cooling water pipe 49 which connects the heat exchangers in series and in which the cooling water passes; and a pump 34 that conveys the chemical solution. The temperature of the chemical solution in the chemical solution reservoir 31 is lower than that of the cooling water. The pipe 32 sequentially connects the chemical solution reservoir 31, the first heat exchanger, the second heat exchanger and the plant. The cooling water guided from the inside of the plant passes through the second heat exchanger and subsequently passes through the first heat exchanger.

Abstract: A straightening device for welding wire is provided with two sets of roll groups, having a plurality of straightening rolls with which bends in a welding wire are straightened by passing the welding wire through the two sets of roll groups. The plurality of straightening rolls configuring the roll groups, are arranged at a predetermined arrangement interval along a passing direction of the welding wire in such a way as to face with each other across a straightening path along which the welding wire passes, and the two sets of roll groups, are arranged so that the directions in which they face across the straightening path are different from each other. By configuring the straightening rolls by small-diameter rollers, adverse effects on the welding wire are suppressed, and the welding wire is straightened finely.

Abstract: A method for injecting a corrosion inhibitor injecting an oxidant and an anticorrosive agent-pH adjusting agent complex including an anticorrosive agent and a pH adjusting agent adsorbed on a surface of the anticorrosive agent into high temperature water in contact with a surface of a metal structural material and irradiating the high temperature water with a radioactive ray or an ultraviolet ray, wherein the anticorrosive agent of the anticorrosive agent-pH adjusting agent complex has, on the surface of the anticorrosive agent, an active site where the pH adjusting agent reacts with the oxidant, and the pH adjusting agent present on the surface of the anticorrosive agent of the anticorrosive agent-pH adjusting agent complex and/or in the high temperature water is oxidized with the oxidant by the irradiation with the radioactive ray or the ultraviolet ray to change pH adjusting ability of the pH adjusting agent and shift a pH of the high temperature water to a neutral side, and thereby deposition of the antic

Abstract: The present invention provides a corrosion-resistant structure for a high-temperature water system comprising: a structural material 1; and a corrosion-resistant film 3 formed from a substance containing at least one of La and Y deposited on a surface in a side that comes in contact with a cooling water 4, of the structural material 1 which constitutes the high-temperature water system that passes a cooling water 4 of high temperature therein. Due to above construction, there can be provided the corrosion-resistant structure and a corrosion-preventing method capable of operating a plant without conducting a water chemistry control of cooling water by injecting chemicals.

Abstract: The present invention provides a corrosion-resistant structure for a high-temperature water system comprising: a structural material 1; and a corrosion-resistant film 3 formed from a substance containing at least one of La and Y deposited on a surface in a side that comes in contact with a cooling water 4, of the structural material 1 which constitutes the high-temperature water system that passes a cooling water 4 of high temperature therein. Due to above construction, there can be provided the corrosion-resistant structure and a corrosion-preventing method capable of operating a plant without conducting a water chemistry control of cooling water by injecting chemicals.

Abstract: A photocatalyst injection system including: a reactor primary system coolant collection section collecting a reactor primary system coolant containing a noble metal or noble metal ion from a reactor primary system; a photocatalyst addition section adding a photocatalyst to the collected reactor primary system coolant; an ultraviolet irradiation section irradiating, with ultraviolet rays, the coolant to which the photocatalyst has been added for producing, in the coolant, a noble metal-carrying photocatalyst in which the noble metal is carried on a surface of the photocatalyst; and a noble metal-carrying photocatalyst injection section injecting the coolant containing the noble metal-carrying photocatalyst into the reactor primary system.

Abstract: The present invention provides a corrosion-resistant structure for a high-temperature water system comprising: a structural material 1; and a corrosion-resistant film 3 formed from a substance containing at least one of La and Y deposited on a surface in a side that comes in contact with a cooling water 4, of the structural material 1 which constitutes the high-temperature water system that passes a cooling water 4 of high temperature therein. Due to above construction, there can be provided the corrosion-resistant structure and a corrosion-preventing method capable of operating a plant without conducting a water chemistry control of cooling water by injecting chemicals.

Abstract: Provided is a method for monitoring corrosion in a power plant, including: forming a film with a composition of M1FeO3 (M1 is a trivalent or tetravalent metal) or M2Fe2O4 (M2 is a divalent metal) on the inner wall surface of an apparatus of the power plant; and maintaining the film stably by controlling the amount of introduction of oxygen into the apparatus commensurate with a temperature in the apparatus.

Abstract: A method for injecting a corrosion inhibitor injecting an oxidant and an anticorrosive agent-pH adjusting agent complex including an anticorrosive agent and a pH adjusting agent adsorbed on a surface of the anticorrosive agent into high temperature water in contact with a surface of a metal structural material and irradiating the high temperature water with a radioactive ray or an ultraviolet ray, wherein the anticorrosive agent of the anticorrosive agent-pH adjusting agent complex has, on the surface of the anticorrosive agent, an active site where the pH adjusting agent reacts with the oxidant, and the pH adjusting agent present on the surface of the anticorrosive agent of the anticorrosive agent-pH adjusting agent complex and/or in the high temperature water is oxidized with the oxidant by the irradiation with the radioactive ray or the ultraviolet ray to change pH adjusting ability of the pH adjusting agent and shift a pH of the high temperature water to a neutral side, and thereby deposition of the antic

Abstract: The present invention provides a corrosion-resistant structure for a high-temperature water system comprising: a structural material 1; and a corrosion-resistant film 3 formed from a substance containing at least one of La and Y deposited on a surface in a side that comes in contact with a cooling water 4, of the structural material 1 which constitutes the high-temperature water system that passes a cooling water 4 of high temperature therein. Due to above construction, there can be provided the corrosion-resistant structure and a corrosion-preventing method capable of operating a plant without conducting a water chemistry control of cooling water by injecting chemicals.

Abstract: According to one embodiment, there is provided a method for monitoring corrosion in a power plant, including: forming a film with a composition of M1FeO3 (M1: trivalent or tetravalent metal) or M2Fe2O4 (M2: divalent metal) on an inner wall surface of each of apparatuses of the power plant; and maintaining the film stably by controlling an amount of introduction of oxygen into each of apparatuses commensurate with a temperature in each of the apparatuses.