EURO-ECO 2010 Hanover 2 - 3 Dezember 2010	Environmental, Engineering - Economic and Legal Aspects for Sustainable Living
	European Academy of Natural Sciences, Hanover European Scientific Society, Hanover University of Bremen, Bremen

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The production of primary aluminium is one of the activities of blue chip companies of home industry providing Russia’s modern economic well-being. By these companies the production process is declared to be one of the most safety for people and environments. Nevertheless there is an influence for environments both by aluminium and other metallurgical productions.

Alumina (Al₂O₃) is the raw material for producing primary aluminium. While smelting of aluminium one should use about two tons of alumina; 0,5 ton of carbon anodes; 0,03 ton of aluminium fluoride AlF₃; 0,0015 ton of cryolite Na₃AlF₆ for getting one ton of metal. As a result of smelting aluminium from 0,3 to 0,8 tons of complicated chemical and mineral composition wastes are formed. They are transported into slime reservoirs by hydraulic way. This wastes were found to consist of C (12…85%), F (13…32%), Al (11…33%), Na (3…17%), Fe (0,4…3%), S (0,05…2,5%), Si (0,05…0,5%) and other elements. The emission of wastes pollutes air, rivers, and ground waters.

Alumina is surely the main source of chemical contamination of environments because it forms the largest part in smelting of aluminium. We analyzed four industrial alumina samples produced at the four plants from different ores. The first sample was produced at Achinsk Alumina Combine from nepheline syenite, the second sample was produced at Bogoslovski Aluminium Plant from Ural bauxite, the third sample was produced at Nikolayevski Alumina Plant (Ukraine) from Guinea bauxites, and the fourth sample was produced at Pavlodarski Aluminium Plant (Kazakhstan) from Turgay bauxite.

Chemical elements in all samples were analyzed with chemical and ICP MS methods. Analyses showed that there are from 0,6 to 0,7% of toxic trace elements in industrial alumina (table). Table. Concentration’s Ranks of Chemical Elements in Alumina

Concentration’s Ranks, ppm	Chemical Elements
1 000 000 – 10 000	Al
10 000 – 1 000	Na
1 000 – 100	C; Ca; S; K; Rb; Si; F
100 – 10	Mg; P; Zn; Zr; Ti; Ga; B; As; Ce; Mo; Mn; V; Sr
10 – 1	Cr; Li; Ni; Be; Cu; Sn
<1	Hg

The concentrations of approximately 10 elements exceed their Clarke values (or the average values of a chemical elements in the Earth’s crust). Such dangerous elements as Mo, As, Be, Hg, S are characterized by especially active accumulation in alumina. The highest concentrations of toxic elements are found in alumina from Paleozoic bauxites while the minimum ones are observed in alumina from young Cenozoic ores and from nepheline syenite. Thus, alumina can provide a chemical pollution of environments.

The aluminium production in Russia is not sufficiently supplied with home mineral resources, and about 60% of alumina is imported. And toxic elements are imported together with alumina of course. After alumina processing (aluminium smelting) many toxic trace elements are left in Russia in the form of wastes that pollute home environment. We consider that annually it is about 25-30 thousands metric tons of toxic elements.

 

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