Treatment of Lead Slag by Reduction Smelting
Lead slag is a waste generated during the refinement of crude lead from lead ore concentrate. It is a heavy, non-toxic, hazardous material that pollutes the environment and causes long-term health hazards. Lead slag can be processed into lead products by reduction smelting.
The reduction smelting of lead slag includes the following steps:
1. Reduction smelting process: The billet of low-grade lead is placed in the roasting furnace, and a certain amount of fuele is added to start the roasting furnace and keep it burning. The fuel used in this process is generally coke and anthracite, and sometimes charcoal is used. During the reduction smelting process, these fuel gases and ash are discharged through the exhaust pipe. Meanwhile, the temperature and oxygen content of the slag reduction furnace are strictly controlled to keep them at the optimal values.
2. Impurities Removal: Slag in the reduction smelting process is also contaminated with many impurities, such as mercury, arsenic, and antimony. To remove these impurities, flotation or liquid-liquid separation technology is often used after reduction smelting. After the impurities in the slag are removed, the lead content of the slag is further improved.
3. Lead Slag Processing: After the lead slag is impurity-removed, it must be cast for further processing; the lead slag is melted, and the molten lead is tapped and formed into ingots or products of various shapes. The lead slag can also be further processed into lead powder.
The reduction smelting process can greatly improve the economic value of waste lead slag and reduce the environmental pollution caused by lead slag. At the same time, this method can recoup some of the costs of lead production and provide a steady source of income.
Although the reduction smelting process is relatively simple and efficient, it should be noted that the temperature in the reduction furnace should be strictly controlled to ensure the quality of the lead slag. In addition, the lead content of the lead slag should be tested to ensure that the lead content meets the requirements of the production process. During the reduction smelting process, regular cleaning of the equipment should be performed to ensure the smooth flow of the production process and reduce the production cost.
