In addition to minerals, the so-called gangue is also a part of mineral raw materials. What it is? Why did they get such a name? The answer to these questions will be briefly given in the article. In addition, it will briefly describe what enrichment is, and its practical significance is described.
Scientific definition
By waste rocks in science and industry we mean rocks that are of no practical value. They usually accompany mineral deposits, and often they are not so easy to separate - this requires special processing processes.
So, waste rock, for example, consists of oxides of aluminum, calcium, magnesium, silicon. The minerals formed by them are called silicates, aluminosilicates.
As the Mountain Encyclopedia explains, waste rocks are extracted from the bowels of the earth along with minerals and sent to dumps - places of placement on the surface of substandard mineral raw materials. By dumping, the so-called overburden works at quarries are usually completed, which open access to minerals and prepare them for excavation. Well-known waste heaps are nothing more than dumps - mountains of waste rock, extracted from mines or (near mining plants) which is an enrichment waste.
What is enrichment
Enrichment is applied if waste rock cannot be completely separated from minerals for any reason. This term refers to the processes of primary processing of mineral raw materials. The goal is the separation of valuable minerals from waste and from each other. Indeed, in iron ore, for example, in addition to the rocks considered by us, other valuable minerals can also be contained - oxides of nickel, molybdenum, vanadium, chromium, manganese, tungsten.
Enrichment involves several stages, in which, in turn, certain operations are carried out. So, the preparatory stage includes the processes of crushing and grinding, screening (separation of rock particles according to size) and classification.
At the main stage, useful components are extracted from raw materials - one or more. To do this, they rely on the differences between waste rocks and minerals and the latter from each other in electrical conductivity, wettability, density, magnetic susceptibility, chemical properties, solubility, etc. The final stage involves the dehydration and drying of the processed products.
Enrichment process result
As a result of enrichment, concentrated rocks are prepared, ready for processing, and so-called dump tailings, consisting mainly of waste rocks. Valuable minerals are practically absent in them or are present in such a concentration that further processing of such raw materials is simply inexpedient. In addition, in the enrichment process, intermediate products can also be obtained, the concentration of useful components in which is higher than in waste, but lower than in the target products.
The enrichment process is carried out at enrichment plants, next to which mountains of waste rock gradually grow.
Waste management
Despite their apparent futility, these rocks can be used in industry and construction. So, they are used in reclamation, in road construction, they fill the mine workings, and ravines fall asleep. Many of the waste rocks, previously considered unnecessary, have found their application in modern industry, for example, the Khibiny nepheline. Previously, when receiving apatite concentrate, nepheline was sent to waste, but now, thanks to scientific research, it is used in a number of industries. Thus, waste rock, despite its telling name, can be successfully applied and bring benefits.