(1. 中南大學(xué)冶金科學(xué)與工程學(xué)院，長沙 410083;
2. 湖南工業(yè)大學(xué)冶金工程學(xué)院，株洲 412007)
摘 要: 針對鉛鋅混合硫化精礦燒結(jié)-密閉鼓風(fēng)爐還原熔煉工藝(ISP)熔煉溫度高、能耗大和大氣污染嚴(yán)重等弊端，提出一種低溫熔鹽煉鉛分離鉛鋅的新工藝。采用單因素實驗法研究固硫劑ZnO和碳酸鈉的用量、熔煉溫度及熔煉時間等工藝參數(shù)對鉛的直收率及ZnO固硫率的影響。結(jié)果表明：確定最佳條件為ZnO擴大實驗的結(jié)果良好和精礦的質(zhì)量比為0.36:1，碳酸鈉和精礦的質(zhì)量比為3.2:1，熔煉溫度為880 ℃和熔煉時間為60 min。在此優(yōu)化條件下擴大實驗的結(jié)果良好：鉛直收率為97.15%，粗鉛品位為98.52%，ZnO固硫率為95.42%，水浸渣含Zn 55.80%(質(zhì)量分數(shù))。XRD物相分析表明：硫主要被固定在ZnS中，Na2CO3熔鹽的物相未發(fā)生改變，可循環(huán)使用。
關(guān)鍵字: 硫化精礦；碳酸鈉熔鹽；固硫；熔煉
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China;
2. School of Metallurgy Engineering, Hunan University of Technology, Zhuzhou 412007, China）
Abstract:In view of serious shortcomings, such as high smelting temperature, large energy consumption and atmospheric contamination, existed in the imperial smelting process (ISP), a low-temperature molten salt smelting process to directly produce lead from the lead and zinc mixed sulfide concentrates was proposed. The influencing factors, including the smelting temperature, reaction time and dosage of ZnO and salt, were investigated in detail using single-factor experiments. The results show that the optimum conditions are determined as follows: mass ratio of ZnO and concentrate is 0.36:1, mass ratio of Na2CO3 and concentrate is 3.2:1; smelting temperature is 880 ℃ and smelting time is 60 min. Under above-mentioned optimum conditions, some encouraging results are obtained as follows: the direct recovery rate of lead reaches 97.15%, the grade of crude lead reaches 98.52%, the sulfur-fixing rate for ZnO reaches 95.42%, the mass fraction of zinc in the leaching slag is 55.80% (mass fraction). The XRD results indicate that sulfur is mainly fixed in the form of ZnS, whereas, the Na2CO3 molten salt does not react with other components, serving only as a reaction medium.
Key words: sulfide concentrate; soda molten salt; sulfur-fixing; smelting
