Abstract:Due to its strong adaptability of raw materials, stable and reliable operation of smelting furnace, high metal recovery rate and high sulfur dioxide concentration in smelting flue gas of oxidation furnace, the process of direct reduction of high liquid lead slag in oxygen-rich blowing bath smelting plays an increasingly important role in lead smelting industry. However, at present, the theoretical basis of the process is relatively weak, and it is urgent to carry out theoretical research on the thermodynamic balance of smelting process, so as to provide theoretical support for the optimization of process. The process mineralogy of metallurgical process materials such as lead concentrate, high lead slag and reduction slag was studied. The influence law of oxygen coefficient in oxidation section, melting temperature and reducing agent dosage in reduction section on Pb distribution rate and content of Pb, S and other elements in smelting slag was studied by FactSage8.1 thermodynamic software calculation. It is calculated that the direct yield of lead in oxygen-rich bath oxidation smelting reaches the highest when the oxygen coefficient is 1.0 and the melting temperature is about 1 200 ℃. The increase of temperature and addition of FeO and CaO are beneficial to the reduction of high lead slag. When the amount of reducing agent is more than 5.7%, the reduction rate of lead can reach 91%.