Evidence suggests that blast furnaces, that convert raw iron ore into pig iron, which can be remelted in a cupola furnace to produce cast iron by means of a cold blast and hot blast, were operational in China by the late Spring and Autumn period (722–481 BC). The bloomery was nonexistent in ancient China; however, the Han-era Chinese produced wrought iron by injecting excess oxygen into a furnace and causing decarburization. Cast iron and pig iron could be converted into wrought iron and steel using a fining process. COUNT 5
QSN1 What type of furnace was functional in China in 722 BC? ANS1 blast QSN2 What element was used in the production of wrought iron? ANS2 oxygen QSN3 What type of iron could pig iron be converted into? ANS3 wrought QSN4 What type of process was used to convert various metals into steel? ANS4 fining QSN5 What can iron ore be converted into in a blast furnace? ANS5 pig iron