METHOD OF INHIBITING CORROSION OF CARBON STEEL AND CORROSION INHIBITION LIQUID FOR CARBON STEEL

• Main Authors: ISHIOKA SHINICHI, IWANAMI MASARU, FUJII KAZUMI
• Format: Patent
• Language: English; Japanese
• Published: 05.02.2015
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE

PROBLEM TO BE SOLVED: To considerably inhibit corrosion of a carbon steel contacting a solution containing chloride ion such as seawater in such solution environment.SOLUTION: A method of inhibiting corrosion of a carbon steel is provided in which a corrosion inhibitor-containing solution is prepared by adding NaMoOand NaNOto a chloride ion-containing solution contacting the carbon steel and the corrosion inhibitor-containing solution is deaerated. In the method, NaMoOcontained in the corrosion inhibitor-containing solution is set to be in the range of 50 to 5,000 ppm, and NaNOcontained in the corrosion inhibitor-containing solution is set to be in the range of 50 to 500 ppm. In another embodiment, solution in which NaMoOand NaNOare dissolved in water (corrosion inhibition liquid for carbon steel) is prepared and is injected to the chloride ion-containing solution contacting the carbon steel, and the resultant solution is used. 【課題】海水等の塩化物イオンを含む水溶液環境下で当該水溶液と接する炭素鋼の腐食を大幅に抑制する。【解決手段】炭素鋼と接する塩化物イオンを含む水溶液にＮａ２ＭｏＯ４及びＮａＮＯ３を添加して腐食抑制剤含有液とし、腐食抑制剤含有液に脱気を施す炭素鋼の腐食抑制方法において、腐食抑制剤含有液に含まれるＮａ２ＭｏＯ４は５０〜５０００ｐｐｍの範囲となるようにし、腐食抑制剤含有液に含まれるＮａＮＯ３は５０〜５００ｐｐｍの範囲となるようにする。Ｎａ２ＭｏＯ４及びＮａＮＯ３を水に溶解した溶液（炭素鋼用腐食抑制液）を作製し、炭素鋼と接する塩化物イオンを含む水溶液に注入して用いてもよい。【選択図】図３