Assertion: oxygen | /r/ObjectUse | used in second step of iron processing
Facets:
value: in the bessemer converter
type: LOCATION
value: in basic oxygen process method
type: OTHER
value: in open hearth
type: LOCATION
Source sentences:
text: Oxygen is then used in a second step of iron processing in the Bessemer converter, open hearth, or basic oxygen process method of converting "pig iron" to steel.