【作者】 王苹；

【导师】 董风芝；

【作者基本信息】 山东理工大学 ， 矿物加工工程， 2011， 硕士

【摘要】 硫铁矿烧渣是以硫铁矿为原料生产硫酸过程中排放出的废渣。硫铁矿烧渣中一般含铁30%-60%。利用硫铁矿烧渣选出铁精粉可以使硫铁矿烧渣作为我国铁资源的-种补充。我国硫铁矿烧渣中硫杂质含量普遍较高,一般1%-4.8%左右。硫会造成钢的热脆性,使其延展性及韧性降低,特别是冲击值或冲击韧性降低。部分硫铁矿烧渣砷含量较高,一般0.2%-0.65%左右。砷作为一种有害元素,它能使钢铁产品产生冷脆,影响铸铁的显微组织,导致铸铁力学性能降低,还会造成一系列的工艺问题和环境问题。要综合利用硫铁矿烧渣,脱硫除砷成为研究的热点。本论文先分别对国内外硫铁矿烧渣的利用现状、硫铁矿的选铁和除硫现状以及某些矿石的除砷现状做了相关的分析。针对武汉某化工公司的硫铁矿烧渣进行研究,分析了烧渣中主要矿物形态、赋存状态等。根据工艺矿物学,分析了用重选、磁选、浮选等一系列工艺的可行性,选择用弱磁选回收烧渣中的铁。为了进一步提高精矿中铁品位和脱除精矿中的硫、砷杂质,对弱磁选的精矿分别进行浮选试验和化学浸出试验。试验结果表明,浮选除杂效果不明显,选用化学浸出进行除杂提品位。通过对各种影响因素进行单因素试验,确定了弱磁选和化学浸出试验的最佳工艺参数。最佳工艺条件为：磨矿细度为-0.038mm粒级占80%,磁选给矿浓度为40%,磁场强度0.2 T；用盐酸做浸出药剂,矿浆浓度调成40%,酸固比为1：25,搅拌强度为150 r/min,浸出时间40 min,废酸滤除后精矿用水洗涤三次。硫铁矿烧渣中TFe含量为51.06%,硫含量为1.51%,砷含量为0.51%,经弱磁选-化学浸出,最终能够制备出铁品位为63.35%,硫含量为0.325%,砷含量为0.083%的合格铁精粉。该研究可利用硫铁矿烧渣制备合格的铁精粉,对降低炼铁成本、缓解铁矿资源紧张状况、提高资源的综合利用率、保护环境等方面都具有重要的现实意义。更多还原

【Abstract】 Pyrite cinder is the waste of the process of the acid production which using the pyrite as the raw material. The content of the iron in pyrite cinder is 30%-60% in general. Using the pyrite cinder to produce iron concentrate can make the pyrite cinder to be complement to our iron resources in some degree. The content of sulfur in pyrite cinder is higher in China, and it is about 1-4.8%. Sulfur can cause the steel to be thermal brittleness, which can reduce the ductility and toughness, particularly, the impact value and toughness. Some pyrite cinder has high level arsenic, which is about 0.2-0.65%. Arsenic can make steel cold crisp, influence the microstructure of the steel and reduce the mechanical properties. Arsenic can also cause a series of technological problems and environmental issues as a harmful element. Removing the sulfur and arsenic in comprehensive utilization of pyrite cinders is the research focus.In this thesis, the status of the utilization of the pyrite cinder, the status of iron recovery and desulfurizing, and the status of removing the arsenic for some ore are summarized respectively. This thesis researches on the pyrite cinder of a chemical company in Wuhan and analyzes the mineral forms and occurrence of the cinders. It also analyzes the feasibility of the gravity concentration, magnetic separation and froth separation based on the process mineralogy. Low intensity magnetic separation is used to recover the iron, while froth flotation and chemical leaching are used to remove sulfur and arsenic respectively. The result proves that the removal of impurities by froth flotation is not obvious, so chemical leaching is used to removing impurities and improving the iron grade. The optimal parameters of low intensity magnetic and chemical leaching are determined by single factor tests. The optimal conditions are displayed as followed. The grinding fineness is that the size fraction less than 0.038 mm occupies 80%. The concentration of the magnetic separation is 40%, and the magnetic intensity is 0.2 T. Using the hydrochloride as the leaching reagent, making the concentration 40%, setting the ratio of acid and solid at 1:25, the pyrite cinder are leached in 40 minutes when the stirring speed is 150r/min. The concentrate is cleaned for three times with water. Through the low intensity magnetic separation and chemical leaching, qualified iron concentrate can be got, in which the grade of iron is 63.35%, the content of sulfur is 0.325%, and the content of arsenic is 0.083%.This research is used to prepare the qualified iron concentrate from pyrite cinders, which have important significance in reducing the iron cost, relieving the tension of iron resources, improving the comprehensive utilization of the resources and protecting the environment.更多还原