The specific method belongs to patented technology and I can't tell you.
Hard zinc is a by-product of pyrometallurgy of crude zinc, which contains about 90% zinc and rare and precious metals such as germanium, indium and silver. A new technology and process for extracting zinc by vacuum distillation and enriching germanium, indium and silver are adopted to treat hard zinc. While zinc volatilizes to produce crude zinc, rare and precious metals such as germanium, indium and silver are enriched in distillation residue.
The developed technology is the first at home and abroad, with the patent number ZL98 107600.9. In June 2003, it won the second prize of national technological invention and the first prize of Guangdong Science and Technology Progress in June 2003. No "three wastes" pollution, belonging to "green metallurgy" new technology. Compared with the traditional flame-proof furnace-electric furnace process, this process has the characteristics of short process, simple equipment, small floor space, less investment, low energy consumption, less pollution, high metal recovery rate and good working conditions, and has remarkable economic and social benefits. At present, 4 sets use 8 sets, the cumulative output value has exceeded 654.38+0 billion yuan, and the new profits and taxes have exceeded 300 million yuan.
The main economic indicators are as follows:
(1) power consumption: ~ 1800 degrees/ton of hard zinc;
(2) smelting time:16h/furnace;
(3) Production capacity: 2.5 tons of hard zinc per furnace;
(4) The produced crude zinc contains zinc: > 99%;
(5) The direct yield (%): zinc ~90, germanium 96. 14, indium 98.38, with almost no loss of silver;
(6) Enrichment multiple: germanium, indium and silver are all 10 times;
(7) Infrastructure investment: ~ 600,000 yuan/set;
(8) Unit cost: ~ 1200 yuan/ton of hard zinc.
Implementation conditions: Pyrolysis Zinc Plant is used to treat hard zinc, with workshop area of150m2 and capacity of 415kW. The workshop needs to be equipped with a 2-ton crane with a lifting height of 8 meters. The total investment for building a furnace with a loading capacity of 2.5 tons is 600,000 yuan.
Benefit analysis: the economic benefit of treating hard zinc per ton is about 2000 yuan, and a large number of pyrometallurgical zinc plants at home and abroad need this technology and equipment.