矿石浓度是什么意思?
金属在矿石中与其他元素形成络合物。从矿石中去除金属的过程称为金属提取。从矿石中提取金属并将其精炼的方法称为冶金。所有的金属都不能用一个单一的过程来提取。根据金属的不同,使用的工艺也会有所不同。从矿石中提取金属的最关键阶段之一是矿石浓缩,也称为矿石富集。
什么是矿石?
Ore is defined as a solid substance (such as a rock) that includes minerals or a combination of minerals, from which metal can be recovered by a series of procedures such as ore concentration, metal isolation, and metal refining. Ores are broadly categorized into four types:
- 原生矿石:这些是非反应性矿石,包括处于游离状态的金属。例子包括银、金和铂。
- 氧化矿石:这些含有氧化物或含氧盐,即金属碳酸盐、磷酸盐和硅酸盐。氧化物矿石(Fe 2 O 3 )和碳酸盐矿石是两个例子(CaCO 3 )。
- 硫化矿石:这些含有金属硫化物,如铁和铅。示例包括 FeS 2 (黄铁矿)、PbS(方铅矿)和 HgS(朱砂)。
- 卤化物矿石:金属卤化物存在于其中。氯化物矿石:AgCl(角银)、CaF 2 (萤石)等。
什么是浓度?
Concentrating ore is a method of removing gangue particles and other impurities. Alternative names for ore concentration include ore-dressing and benefaction. The procedure of ore concentration is a critical stage in obtaining pure metal from ore. Separating ore from gangue particles is required for metal extraction.
在土壤中发现的矿石中含有沙子、砂砾、鹅卵石等多种杂质,统称为“脉石”。金属提取的第一步是选矿。有几种形式的矿石,例如天然矿石、氧化矿石、硫化矿石和卤化矿石,可以使用各种物理和化学过程进行浓缩。
矿石选矿方法
由于矿石位于地球表面,因此它含有不受欢迎的土质成分,例如巨石、沙子、淤泥和各种其他通俗称为脉石的杂质。专注是将有用的事物与无价值的事物分开。因此,我们可以通过从这些污染物中浓缩矿石来回收和提炼金属。为了从脉石基质中浓缩或提取矿石,使用了各种物理和化学程序。
选矿的物理方法
选矿的物理方法包括人工采摘、水洗、磁选和泡沫浮选。
手工采摘
这是传统的用手直接选矿的方法。在这种技术中,使用锤子从矿石中去除脉石或粘附的固体基质。脉石分离和识别是基于颜色或块状的区别。
液压清洗
它也被称为“重力分离”或“Levigation”。这个过程通过使矿石通过向上的水流来浓缩矿石,将较轻的脉石颗粒与较重的金属矿石分离。这是一种重力分离。
磁选
这包括使用矿石或脉石的磁性特征分离矿石和脉石。矿石首先被粉碎成细颗粒,然后通过磁辊传送到传送带上。磁性矿石留在皮带上,而脉石则脱落。
泡沫浮选法
该技术主要用于从硫化矿石中提取脉石。矿石被粉碎,形成在水中的悬浮液。这辅以收集器和泡沫稳定剂。捕收剂(松油、脂肪酸等)增加矿石金属成分的非润湿性并使其形成泡沫。甲酚、苯胺和其他泡沫稳定剂将泡沫保持在原位。金属靠油润滑,脉石靠水润滑。泡沫是通过用桨和空气不断搅拌悬浮液产生的。泡沫金属从顶部撇去并干燥以回收金属。以下是浮选阶段:
- 浮选的初始阶段是粗选。在此操作期间提取的有用材料最多。在粗加工之前,有时会使用预浮选程序。这样做是为了去除有机碳等污染物。
- 清洁是浮选过程的下一步。在此过程中删除不需要的内容。此步骤的输出称为清洁剂浓缩物。
- 浮选过程的最后阶段是扫气。这样做是为了回收在粗加工期间未收集的关键材料。
Chemicals of flotation process
- Anionic Sulphur ligands serve as collectors. For instance, xanthate salts. Fatty acids and fatty amines are also utilised as collectors.
- Frothers are employed to keep the froth stable. For example, pine oil, alcohols, and so on.
- To optimise the separation process, modifiers are utilised. Lime (CaO), Caustic soda (NaOH), and other pH adjusters are available. Phosphates, silicates, and carbonates are examples of anionic modifiers. Organic modifiers include thickeners such as dextrin, starch, glue, and others.
浸出
当矿石可溶于溶剂时,进行浸出。粉状矿石溶解在化学物质中,通常是强 NaOH 溶液。矿石中的金属被化学溶液溶解,通过化学溶液的萃取,可以将其从脉石中回收分离。该方法用于从铝土矿中提取金属铝。
选矿的化学方法
为了提高浓度,使用了煅烧、焙烧和浸出等化学工艺。
煅烧
煅烧是通过快速加热将矿石转化为氧化物的过程。在没有空气或供应受限的情况下,矿石被加热到其熔点以下。该过程经常用于将碳酸盐和氢氧化物转化为其相应的氧化物。在煅烧过程中也消除了水分和挥发性污染物。煅烧是一种热过程,用于通过加热分解矿石和其他固体材料来转化它们。煅烧中的反应大部分时间发生在热分解温度或以上。因此,煅烧主要用于将石灰石(碳酸钙)转化为石灰(氧化钙)和二氧化碳。
CaCO 3 ⇢ CaO + CO 2
烘烤
这是一种冶金过程,在该过程中,通过在存在额外空气的情况下将矿石加热到其熔点以下,将其转化为氧化物。虽然煅烧通常用于碳酸盐氧化,但焙烧是一种转化硫化矿的过程。水分和非金属污染物在烘烤过程中作为挥发性气体排放。氧化、还原、硫酸化、氯化和热解等固气热过程构成了焙烧过程。然而,硫化物焙烧是空气污染的主要来源,这种方法的主要缺点是会排放大量影响环境的金属、有毒和酸性物质。
2ZnS + 3O 2 ⇢ 2ZnO + 2SO 2
浸出
这是一个化学过程,其中矿石用适当的试剂处理以溶解它。将可溶性矿石或矿物与不溶性脉石分离是可能的。矿石分离后,可以使用多种化学技术进行回收。
示例问题
问题一:什么是精选?
回答:
It was the old way of directly concentrating ore with the hands. With the use of a hammer, the gangue or adhering solid matrix is removed from the ore in this procedure. The separation and identification of gangue is based on colour or lump form differences.
问题2:什么是浸出?
回答:
It is a chemical process in which the ore is treated with the appropriate reagent to make it soluble. Separating the soluble ore or mineral from the insoluble gangue is possible. Several chemical processes can be used to recover ore once it has been separated.
问题3:浮选的三个阶段是什么?
回答:
- Roughing is the initial step in the flotation process. The largest amount of useful material is extracted during this operation. Before roughing, the pre-flotation phase is sometimes used. This is done to get rid of contaminants like organic carbon.
- The next phase in flotation is cleaning. Unwanted content is deleted during this process. Cleaner concentration is the end result of this stage.
- The final phase in the flotation process is scavenging. This is done to recover essential materials that were not recovered during the roughing process.Scavenging is the last step of the flotation process. This is done to recover essential materials that were not recovered during the roughing process.
问题4:什么是矿石?
回答:
Ore is a solid substance (like a rock) that includes minerals or a combination of minerals from which metal can be recovered using a variety of procedures such as ore concentration, metal isolation, and metal refining.
问题5:什么是磁选?
回答:
Magnetic properties of either the ore or the gangue are utilised to separate the ore and gangue. The ore is first finely processed before being conveyed on a conveyor belt that passes past a magnetic roller. The magnetic ore stays on the belt, while the gangue slides off.