材料期刊网

硫酸烧渣是硫铁矿制酸氧化焙烧产物;从硫酸烧渣中选铁的工艺技术指标一直不高,其主要原因是硫铁矿氧化焙烧过程中生成的氧化铁矿物颗粒微细,高温时新生成的氧化铁矿物颗粒会与杂质和脉石矿物颗粒相互包裹、相互黏结、相互污染. 该文将硫酸烧渣选铁改为硫精矿再浮选提纯硫化铁,即通过提纯硫酸原料中硫化铁的质量分数,从而去除原料中的脉石和杂质,使硫酸原料中硫品位达到50 % ~52 %(黄铁矿型原料)以上,硫、铁回收率均达到90 % ~92 %;采用该高纯硫精矿制造硫酸,硫酸烧渣中铁品位达到63 % ~67 %,使硫酸烧渣全部直接成为铁精矿,无需再选矿,达到了有效利用硫酸烧渣中铁的目的. 该工艺能够获得较高技术指标的原因是硫精矿除杂提纯浮选是硫化矿选硫,采用高纯硫精矿制酸,避免了非目的矿物污染硫化铁的氧化焙烧过程以及硫酸烧渣选铁时杂质含量高、铁品位低、选矿技术指标低等问题.

Pyrite cinder is the product of oxidizing roasting of pyrite ores. The technical index in iron recovery from pyrite cinder keeps low. The main reason for it is that fine ferric oxide particles produced in the oxidizing roasting process of pyrite ores will in high temperature interact with impurities and gangue minerals including mutual inclu-ding,sticking and polluting. The paper modifies conventional process of iron recovery from pyrite cinder,and turns to a sulfide concentrates flotation process to concentrate ferric sulfide,that is to increase the mass fraction of ferric sulfide in raw materials of pyrites,so that gangue minerals and impurities are removed from the raw materials,reaching a sul-fur grade over 50 % to 52 % and sulfur and iron grade of 90 % to 92 %. The high grade sulfur concentrates are used to made sulfuric acid. The iron in pyrite cinder reaches 63 % to 67 % making the entire cinder directly become iron concentrates without the need of further beneficiation,which is an effective way to utilize the iron in the cinder. The reason for higher technical index lies in the choice of sulfur flotation for impurity removal. High grade sulfur concen-trates making sulfuric acid avoids unwanted minerals hindering the oxidizing roasting of ferric sulfide and high content of impurities,low iron grade and low ore-dressing technical index in the process of iron recovery from pyrite cinder.