Processing of the zinc-lead-bearing flotation middlings by sulfidizing roasting with pyrrhotites production by predicted properties

Abstract

The accumulated amount of lead-zinc ore flotation tailings in the dumps of concentrating plants today can be considered as independent man-made deposits. In addition to their resource value as sources of lead and zinc, as well as associated gold, silver, cadmium, selenium and other metals, tailings are an environmentally hazardous source of heavy metal pollution of ground and surface waters. The environmental hazard of stale tailings is exacerbated by the fact that they occupy large areas that cannot be used for agricultural or other purposes of the national economy. Wastes of flotation enrichment of lead-zinc ores significantly differ from the source material not only in the content of minerals, but also in the degree of oxidation of their surface, fractional composition, and the presence of a significant amount of mineral intergrowths. In view of this, the use of existing flotation technologies is ineffective for obtaining standard lead and zinc concentrates from enrichment tailings. This paper describes the technology that has been developed for processing of zinc and lead-bearing enrichment wastes by sulfidizing roasting followed by magnetic and flotation concentration of cinders. It was found that, as a result of the sulfidizing-pyrrhotizing roasting process, the flotation ability increases for lead compounds and decreases for iron compounds, while the magnetic susceptibility of lower iron sulfides formed during roasting increases. It has been established that sulfidizing takes place with sufficient completeness, and during subsequent flotation, it is possible to extract up to 95% of zinc and up to 80% of lead into sulfide concentrate. These results have a technological advantage in contrast to the other methods that have been used. It was found that at roasting temperatures of 700-800 °C, pyrrhotites have a maximum magnetic susceptibility of 3.75, 5.43 and 2.18 SI units for Fe 0.855 S, Fe 0.888 S and Fe 0.909 S, respectively. Technological recommendations are acceptable for similar raw materials.

Mechanism and technological results of sulfidation roasting of oxidized lead compounds

“…The results of previous studies [ [11], [12], [13], [14], [15], [16], [17], [18]] and the study of the characteristics of roasting products showed that sulfides of non-ferrous metals obtained by sulfidation of oxides and carbonates have high hydrophobic properties, and pyrrhotite, a product of pyrite decomposition, has a significant magnetic susceptibility. All this predetermines further methods for processing sulfidation products.…”

Improvement of the transitional technology from open pit to underground mining of magnetite quartzite

“…One of the most important issues is the monitoring of rock displacements in the areas of open pit fields disturbed by underground mining. Expedient solutions to such problems include analytical methods of studying the geomechanical state of the rock massif, [24,25]. Undoubtedly, the existing technologies of open pit mining of magnetite quartzite when transiting to integrated open pit-underground and subsequent underground mining of iron ore raw materials can be potential sources of man-made disasters.…”

Substantiation the safety open pit wall parameters in the conditions of a reduced protective zone near State critical infrastructure

“…Clay is one of the main minerals for construction, used to produce bricks and other building materials [15,16]. The technology and main indicators of the development of these deposits are influenced by several factors: a) spatial dimensions of the deposits (length, width).…”