Abstract:
PROBLEM TO BE SOLVED: To provide a detergent and method of cleaning, for conducting cleaning and wastewater treatment on an inner wall part or a hard surface of a drinking water storage tank with especially iron rust-based scale attached and the like at low cost, in a short time, in safety, and easily, and having low environmental load.SOLUTION: There is provided a method of manufacturing an aqueous liquid detergent made by dissolving a mixture containing oxalic acid, sodium chloride, and glycerol into water, adjusting insoluble content to a salt concentration around solubility by manufacturing the aqueous liquid detergent with removing oxalic acid or a sodium salt of oxalic acid crystallized at room temperature.
Abstract:
PROBLEM TO BE SOLVED: To provide an oxide film removing test device which can continuously confirm the change with time in removal of scales (oxidized film) remarkably simply.SOLUTION: The oxide film removing test device 10 is used to examine oxide film removing capability by flowing an acid liquid 3 along the surface of a test piece 1 made of metal having an oxide film formed on the surface. The oxide film removing test device 10 includes flow passages 11 to 16, etc. for flowing an acid liquid 2 along the surface of the test piece 1 and having a viewing window 14 through which the surface of the test piece 1 can be observed.