What happens when sand mixed with the steel metal?

Melting point of sand is considerbly lesser than that of steel(sheet metal).

So during the extraction of steel, silica gel(sand) gets collected in the form of slug and is removed as an impurity.

And I do not feel that sand is needed to be included in steel as a mixture except you want to churn the sand in which case, steel balls will be used instead of sheet metal.

slags will flow at the top 

there will be sand inclussion/slag