Slag component analysis method, slag basicity analysis method, and molten iron refining method

A slag component analysis method comprising:

• irradiating a surface of slag to be analyzed with a pulse laser a plurality of times to turn part of the slag into plasma;
• dispersing excitation light obtained from the slag turned into plasma and acquiring an emission spectrum of elements contained in the slag once for every pulse laser irradiation or once for every a plurality of pulse laser irradiations;
• and
• deriving a concentration or component amount ratio of a target component among the elements from acquired emission spectra,
• wherein the slag to be analyzed is slag generated in a converter-type refining furnace, and
• the irradiating the surface of slag to be analyzed is done from a side direction of the converter-type refining furnace tilted to remove the slag generated in the converter-type refining furnace, the side direction being a direction in which an angle between a straight line parallel to a rotation axis of the converter-type refining furnace and an optical path of the pulse laser is 45° or less with respect to the rotation axis of the converter-type refining furnace.