On January 26, the largest tin smelting project in the world - Yunxi tin smelting and returning to the city and entering the park for relocation and transformation project was completed and put into operation in Mengzi economic and Technological Development Zone. The project has invested more than 3 billion yuan, with an annual output of 70000 tons of refined tin, and the annual output of refined tin with full load will account for more than 20% of the global output. As the first non-ferrous mining and smelting project to retreat from the city and enter the park in Yunnan Province, it has a positive effect on the improvement of the ecological environment and human settlements environment in the old cities, which is called "the tin capital".

In the field of tin industry in the world, the project has created many new records, such as the largest scale of production capacity, first-class process facilities, first-class smelting technology, first-class green environmental protection, safety, energy saving, first-class intelligent automation, first-class information management and so on. It represents the first-class technology and equipment level of tin smelting in the world, and will effectively promote the high-end, intelligent and green process of tin smelting.

During the construction of the project, more than 90 patents have been applied, and 90% of the production equipment used is domestically produced, including nearly 40% of the local production equipment in Yunnan. Yunnan's own technology is used in refining tin. The core equipment of the project is vacuum refining furnace developed by Kunming University of science and technology, and the other core equipment is fully automatic electrothermal mechanical crystallizer jointly developed by Kunming University of science and technology and Yunnan Tin Group.

The project is also a green smelting project. It is the only tin smelting project in the world that uses oxygen enriched intensified furnace technology for smelting fuming volatilization and pretreatment of tin concentrate. It is the world's first low concentration sulfur dioxide resource utilization and the first dust denitration tin smelting project. It will produce 33000 tons of industrial sulfuric acid every year, turning harm into treasure while realizing green production, Increase production efficiency.

In addition, the project uses waste heat power generation technology, which can turn waste heat in tin smelting process into more than 58 million kilowatt hours of electricity every year, meeting one third of production power consumption.