中文摘要：

通过焙烧实验探讨了含铊硫铁矿生产硫酸过程中铊的排放特性.结果表明,硫铁矿焙烧过程中,铊排放与焙烧温度、停留时间、焙烧气氛、硫铁矿的粒度等因素有关.不同的温度条件下,铊排放率不同,这主要是与矿石中铊的赋存形态有关;实验条件下,550℃—950℃是Tl排放的主要阶段,Tl排放量约占硫铁矿中总Tl的33.9%.Tl的排放率随停留时间的增加呈现增大的趋势,Tl在10 min的停留时间内急剧排放,此阶段为Tl排放的主要阶段,其排放率达到30.6%.焙烧气氛对铊的排放存在促进或阻滞的影响,氧气流量小于100 mL.min-1时,铊排放率随氧气流量的增加而增加,而氧气流量高于100 mL.min-1时,铊排放率随氧气流量的增加而减小.此外,硫铁矿的粒度对Tl的排放也存在一定的影响,随着硫铁矿粒度的增加,在相同的时间内Tl排放率有降低的趋势.

英文摘要：

In this paper,the characteristics of thallium emission during sulfuric acid production with Tl-containing pyrite roasting were investigated by roasting experiments in tube furnace.Results indicate that thallium emission was dependent on roasting temperature,retention time,roasting atmosphere and particle size of pyrite during pyrite roasting.Emission rates of thallium were different at different roasting temperatures,which were determined by the speciation of thallium present in the pyrite.Under the experimental condition,the main period of thallium emission,which was about 33.9% of total thallium content in the pyrite,was in the temperature range between 550 ℃ and 950 ℃.Thallium emission rates were enhanced gradually with retention time.Thallium was rapidly emitted within the first 10 minutes,with an emission rate of 30.6%.Roasting atmosphere might accelerate or block the emission of thallium.When the flow rate of oxygen was below 100 mL · min-1,thallium emission rates increased with the flow of oxygen,and vice versa.Furthermore,particle size of pyrite also had some effect on thallium emission,with greater particle size of pyrite yielding decreased thallium emission rates.