Kinetic Studies on the Rate of Reaction Between Molten Slag and Metal With Gas-Injection Stirring

Kinetic studies have been made on the rate of reaction between molten slag and metal with gas--injection stirring. The reaction considered is the oxidation of Si in molten Cu by FeO in a Li sub 2 O--SiO sub 2 --Al sub 2 O sub 3 --FeO slag taking place under the condition of rate-controlling by Si transport in the metal phase. Kinetic experiments were done at 1250 deg C. The slag--metal bath was stirred by Ar gas injected through a nozzle located at the crucible bottom. The apparent metal-side mass-transfer coefficients of Si, k sub Si ', are calculated from the kinetic data. Relations between k sub Si ' and experimental conditions (gas flow-rate, V sub g ; metal depth, h sub M ; slag depth, h sub sl ; crucible diameter, d sub c ) were investigated. k sub Si ' was found to increase generally with increasing V sub g . The dependence of k sub Si ' on the gas flow-rate varies at certain gas flow-rates denoted by V sub g * and V sub g