| 摘要 |
<p>PURPOSE:To calcine CaCO3 at lance outlet and supply CaO to a converter without requiring lime furnace, by blowing CaO as flux in shape of CaCO3 together with coal fines and oxygen by lance at melting steel scrap or manufacturing molten pig iron in a top blown converter. CONSTITUTION:At melting steel scrap or manufacturing molten pig or steel in the top blown converter 3, CaO is added as flux. Since CaO is manufactured by calcining CaCO3 in a lime furnace, it becomes expensive while requiring the equipment, fuel for calcining and labor cost. In this case, CaCO3 8 and coal fines 7 crushed to <100 mesh are supplied with gaseous N2 to a top blowing lance 1 and jetted as a jetting flow 6 together with an oxygen 9 from lance top end. The fines 7 are burnt by O2 at lance top end and CaCO3 is calcined to CaO by the heat and it is blasted as CaO powder to form a refining flag 5.</p> |
