基于区位氧势硫势梯度变化下铜富氧底吹熔池熔炼非稳态多相平衡过程

摘要

The multiphase equilibrium state and oxygen-sulfur potential distribution rule of oxygen-enriched bottom blowing smelting (BBS) process were investigated by mechanism model of BBS and oxygen−sulfur potential diagram for Cu-Fe-S-O-SiO2 system. The results show that BBS is at the state of dynamic non-steady approximate multiphase equilibrium of gas−slag−matte three phases coexistence system which is far from equilibrium with continuous feeding, injecting oxygen, slagoff and ejecting matte. And the value of oxygen and sulfur potential changes gradually in different locations of furnace. Oxygen potential decreases and sulfur potential increases gradually from bottom to up in reaction region, separation transition region and liquid phase clarification region, and oxygen and sulfur transfers faster in reaction region with larger oxygen−sulfur potential gradient. The capacity of BBS can be improved by reasonably regulating process parameters to control the value in different layers and regions.%结合富氧底吹熔池熔炼机理模型和 Cu-Fe-S-O-SiO2系氧势−硫势热力学优势图，研究底吹熔炼过程中的多相平衡状态及炉内不同空间位点的氧势−硫势分布规律。结果表明：铜富氧底吹熔池熔炼是烟气−炉渣−铜锍三相共存体系，随着连续加料、连续鼓氧及放渣和放锍操作的进行，体系远未达到平衡，而是处于动态的非稳态近似多相平衡状态，炉内不同空间位点的氧势−硫势不同，存在着梯度变化。反应区、分离过渡区及液相澄清区由下到上氧势逐渐降低，而硫势逐渐升高，其中反应区的氧势−硫势差梯度较大，氧和硫的传质较快。通过调节熔炼过程工艺参数，使炉内不同空间位点的氧势−硫势控制在更为合理的范围，可提高底吹熔炼能力。