| abstract |
PURPOSE: To dissolve and remove the scale adhered to apparatus, etc., safely, effectively, and quickly by bringing an aqueous solution containing both specific anion and aluminium ion into contact with the scale contg. calcium oxalate adhered to the surface of the base material of an apparatus, etc. n CONSTITUTION: An aqueous solution containing both an anion (A): selected from hydrochloric acid, nitric acid, sulfamic acid, formic acid, acetic acid, glycolic acid, oxalic acid, lactic acid, malonic acid, malic acid, tartaric acid, citric acid, and gluconic acid; and aluminum ion (B) is brought into contact with the scale contg. calcium oxalate adhered to the surface of a base material of an apparatus, etc. The preferred proportion of the component (A) to the component (B) is almost 1:1 in equivalent, and also the preferred contacting temperature between the aqueous solution and the scale is 50W70°C. n COPYRIGHT: (C)1981,JPO&Japio |