Chinese
Lead and zinc metals, due to their uniqueness, have an irreplaceable position in industrial development. Lead and zinc metals have a wide range of uses, mainly in the electrical industry, mechanical industry, military industry, metallurgical industry, chemical industry, light industry and pharmaceutical industry. In addition, lead metal is also widely used in the nuclear industry, the petroleum industry and other sectors. This thus promoted the development of the lead-zinc mining industry.
Ii. Process Flow of Lead-Zinc Ore Crushing and Grinding:
The crushing and grinding process flow of the currently operational lead-zinc concentrator is as follows;
Two-stage - closed-circuit crushing - single-stage ball milling
2. Three-stage open-circuit crushing - single-stage ball milling
3. Three-stage open-circuit crushing - rod mill, ball mill
4. Three-stage closed-circuit crushing - single-stage ball milling
5. Three-stage - closed-circuit crushing - two-stage ball milling
6. New three-stage - closed circuit crushing (or four-stage - closed circuit crushing) - two-stage ball milling
Among the above-mentioned several crushing processes, the two-stage - closed-circuit crushing - single-stage ball milling process is more commonly seen in small-scale lead-zinc concentrators with a daily ore processing capacity of less than 500 tons. Three-stage crushing is currently the most widely adopted grinding process in large and medium-sized concentrators. The crushed product has a fine particle size, generally reaching less than 15mm, thus improving the grinding efficiency to a certain extent.
The so-called new three-stage closed-circuit crushing - ball milling process refers to the crushing and grinding process composed of cone crushers and heavy-duty vibrating screens. This process can achieve a crushing particle size of about 6mm, realizing "crushing instead of grinding", reducing the energy consumption of the grinding system, enhancing the processing capacity of the mill, and improving the economic benefits of the beneficiation plant.
Lead-zinc flotation process flow
1. Priority flotation process: This process is mostly used for lead-zinc-sulfur type ores. In principle, lead, zinc and sulfur should be floated in sequence. The process has strong adaptability to changes in ore grade and high flexibility, and is particularly suitable for primary sulfide ores with higher raw ore grades.
2. Fully mixed flotation process: This process is suitable for treating ores with a low total content of sulfide minerals, close symbiotic relationships among minerals, complex structures, and fine particle sizes. The process feature is that it is conducive to energy conservation in grinding. However, the problem of de-dosing in mixed concentrates has not been well solved.
3. Partial mixed flotation process: When the grade of copper or lead in the raw ore is relatively low, this type of process is often more economical.
4. Equal-floatable flotation process: When there are both easily floatable and difficult-to-float sphalerites in the ore, adopting an equal-floatable flotation process mainly composed of lead or copper-lead can achieve better separation results. This process not only retains the advantages of full flotation, where the useful minerals float up without being affected by inhibitors and can float fully, but also overcomes the defect in the full flotation process that the addition of copper sulfate to activate sphalerite makes the separation of lead and zinc difficult.
5. Branching and speed-splitting process: For mines with relatively poor raw ore grades, this process has many advantages. Specifically, it is reflected that the grade of the raw ore can be improved by oneself. The refractory fine particles in one pulp can be floated by using the coarse-grained and easily floating product (foam) with a fast floating speed from the previous pulp as a carrier, or the remaining chemicals in the foam product of the previous pulp can be used to reduce the dosage of the chemicals in the next pulp. All the rough-selected foam products can be concentrated in the next batch for selective processing or by scraping foam at different speeds, etc.
Iv. Flotation collectors: including butyl xanthate, ethyl xanthate, butylamine black medicine, 25# black medicine and 31# black medicine. Secondly, there are ethyl sulfide nitrogen, aniline black medicine and sodium butyl black medicine, etc. The foaming agent is mainly 2# oil, but turpentine oil, concentrated 70# oil, cresol and glycerin oil, etc. can also be selected.
The beneficiation process indicators are as follows: The grade of zinc concentrate is 35%-38%, with some cases reaching 40%. The average recovery rate is around 68%, and the maximum can reach 73%. The dosage of reagents is 10-12kg/t, with the maximum reaching 20kg/t of raw ore.
Equipment power consumption: Approximately 600kw of power per day for processing 500 tons
The daily processing capacity of 1,000 tons of power is approximately 1,200 kW
The daily processing capacity of 2,000 tons of power is approximately 2,300 kW
A daily processing capacity of 3,000 tons generates approximately 3,400 kW of power
The daily processing capacity of 5,000 tons of power is approximately 4,500 kW
The entire system can adopt stepped electricity usage to save energy and reduce consumption. The specific method should be determined according to the actual process.