Question: what is tuyeres in blast furnace?
Answer: A tuyere or tuyère (French pronunciation: ​[tɥijɛʁ]; English: /twiːˈjɛər/) is a tube, nozzle or pipe through which air is blown into a furnace or hearth. Air or oxygen is injected into a hearth under pressure from bellows or a blowing engine or other devices.