English to Polish Law/Patents Chemistry; Chem Sci/Eng stopy aluminium

One more question from the aluminium alloy patent.

The sentence is: "At this time, a stirring time may be different according to the state of an input powder and melt temperature, and it is preferable to stir the melt sufficiently until the added Ca-based additive is, if possible, completely exhausted in the melt."
or
"Herein, the exhaustion means that decomposition of the Ca-based additive is substantially completed."

Basically I've got a problem to describe in Polish what does actually happen with the additive there. Does it mean the it completely dissolves in the melt or completely reacts turning into another compound? If I say "usunięty" will it be ok? Or "rozłożony" or ?