Title : Physical and chemical basis of new process recovery of valuable elements from waste of solid fossil fuels
In fossil coals many fields there is a set of valuable elements, which allows cost-effective to extract them when the content is even lower than in industrial ores. In this regard, very relevant is the problem of scientific justification of process of associated recovery of precious metals and other valuable elements from coals and products of their combustion. Since coal, even with increased content of valuable metals, will not be considered as raw material to produce metals and energy as the raw material from which, after the full use of its energy potential, it is possible to extract valuable elements, noble metals (gold, silver, platinum group metals) and rare earths (lanthanum, yttrium, ytterbium).
To improve the efficiency of extraction of valuable components - noble, platinum group metals, rare earth elements, waste from the combustion of brown coal Kansk-Achinsk basin was studied the process for preparation of the waste to leaching. Based on the analysis of the elements content and distribution in the organic and mineral phases of waste the combustion of brown coal Kansk-Achinsk basin, the data on reactive mode of processing and composition of leach solution the proposed scheme and the initial data for the development of bases of technology of processing of ash and slag waste. The scheme includes crushing, flotation separation of organic part (underburning) and then extraction of the leaching of valuable elements from concentrate and flotation tailings. For the selective leaching of valuable elements from the cakes primary acid treatment is first applied the reagent on the based on phosphinates. Defined reagent modes for these operations.
At the same time of the implementation of the technology of extraction of valuable elements from waste coal combustion is simultaneously prevented the emission of large quantities of hazardous substances (lead, copper, zinc, arsenic, selenium, etc.) in the surrounding space.