Dumps of a mining-metallurgical complex of post-Soviet Republics have accumulated a huge amount of technogenic waste products. Out of them, Kazakhstan alone has preserved about 20 billion tons. In the field of technogenic waste treatment, there is still no technical solution that leads it to be a profitable process. Recent global trends prompted scientists to focus on developing energy-saving and a highly efficient melting unit that can significantly reduce specific fuel consumption. This paper reports, the development of a new technological method—smelt layer of inversion phase. The introducing method is characterized by a combination of ideal stirring and ideal displacement regimes. Using the method of affine modelling, recalculation of pilot plant’s test results on industrial sample has been obtained. Experiments show that in comparison with bubbling and boiling layers of smelt, the degree of zinc recovery increases in the layer of inversion phase. That indicates the reduction of the possibility of new formation of zinc silicates and ferrites from recombined molecules of ZnO, SiO2, and Fe2O3. Calculations show that in industrial samples of the pilot plant, the consumption of natural gas has reduced approximately by two times in comparison with fuming-furnace. The specific fuel consumption has reduced by approximately four times in comparison with Waelz-kiln.

The production activity of mankind using high-ash fossil fuels for electricity generation is steadily increasing ash waste and carbon dioxide emissions into the environment. The article proposes a variant of wasteless combustion of Ekibastuz coal in a melting reactor installed under the boiler; it is envisaged to obtain, in addition to steam of energy parameters, a melt suitable for the production of building materials, sublimates of zinc, gallium and germanium, to reduce emissions of "CO2" into the atmosphere and return to the process a part of carbon in "CO2". An energy-saving thermal diagram of a power plant boiler has been developed on the basis of the proposed technology for the reduction of "СО2, Н2О" of reactor waste gases with zinc vapor to "СО, Н2". The resulting excessive hydrogen will be used to displace elemental carbon from "CO". The spent reagent, zinc oxide, after recovering into zinc will be used again in the process. In case of implementation, CO2 emissions into the atmosphere will be cut up to 50%, the expected payback period of the proposed system will be 1.0 - 1.5 years.

A new system of processing galena concentrates has been developed using the non-blast method of lead reduction from its sulphides by metallic iron. Excavated slag was used as flux agents to generate the stackable sulfur-containing products, instead of sulfuric acid. Based on this relatively modern technical concept of extreme energy saving, the new system of concentrate processing has been developed. The system includes an iron reduction and zinc sublimation system from excavated slag by soot-hydrogenic mixture, products of pyrolysis of natural gases, lead ousting in crude metal from its sulphides by metallic iron in the autogenous conditions of the rotary mixer, regenerative utilization of thermic wastes of the system, and neutralization of SO 2 gases by reagents obtained aboard (ZnO, Fe). The new system will reduce the effective specific equivalent fuel consumption by a factor of 3.77, and it will also expand the utilization factor of material waste products by a factor of 2.5-3 in comparison with the traditional methods of concentrate processing. INDEX TERMS Inversion phase-rotary kiln, galena concentrate, excavated slag, mineral processing, soothydrogenic mixture.

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In the dumps of power plants of the Republic of Kazakhstan, only from the combustion of Ekibastuz coal, ~ 300 million tons of ash have been accumulated, with an annual release of up to 30 million tons. Up to 200 g/t of gallium, germanium, 1 g/t of gold, 4% of zinc, 1% of lead, 0.3% of cadmium and other elements are lost with ash. The work is aimed at unit creation to obtain hydrogen-enriched water gas from ekibastuz coal with the production of Zn, Ga, Ge sublimates, copper-containing cast iron, slag wool and/or cast stone, when joint processing of iron-zinc-contained slag and ash-cinder wastes of thermal power plants.