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Extracellular polymeric substances (EPS) are efficient and environmentally friendly bioflocculants in wastewater pollution that are free from the shortcomings typical of traditional coagulants and flocculants which can pose direct threat to human health and life as well as to the environment. In this paper, the authors have investigated the possibilities of extracting EPS from excess activated sludge and subsequent use of the obtained fractions as reagents for wastewater treatment. The study analyzes the existing methods for extracting EPS, with further selection and implementation of four biopolymer extraction methods. As part of the work, soluble, loosely bound and tightly bound activated sludge EPS fractions were generated using each method. The study of EPS chemical composition demonstrated a significant difference in the obtained fractions from each other; moreover, all the fractions showed the prevailing content of EPS protein components over polysaccharides and humic acids. The most efficient method for extracting proteins from the excess activated sludge biomass is the NH4OH/EDTA method; the one for extracting polysaccharides – the HCHO/NaOH method, and the one for extraction of humic acids – the CH3NO/EDTA method. The study of efficiency of wastewater treatment with the use of obtained fractions has shown that EPS extraction method has an impact not only on the extraction performance, but also on the feasibility of using extracted biopolymers for wastewater treatment. The efficiency of wastewater treatment ranged from 0.2 to 62.6%, depending on the EPS fraction used as a reagent.

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Possibility was examined of using spent solutions of sulfur dioxide gas sorbents, together with sodium sulfi te and pyrosulfi te, for conversion of iron hydrate wastes produced by copper-nickel industries to red iron oxide pigment.Effl uent gases from nonferrous metallurgy plants and exhaust gases of sulfuric acid shops are most frequently purifi ed to remove sulfur(IV) oxide by alkaline purifi cation methods and, in particular, by the sodium sulfi te-bisulfi te technique employing soda ash or its mixture with sodium bicarbonate as SO 2 absorbent. Spent chemisorbents have the form of a dry mixture or a solution of sulfi tes and are wastes that should be buried or utilized [1].In absorption of sulfur(IV) oxide by a soda ash solution, the following processes occur [2]:

On the basis of many years of fi eld ethnographic materials, the authors of the collective monograph made an attempt to reveal the diversity of identities of the ethnocultural groups of Russian old-timers of Siberia and Altai (Chaldons, Siberians, Old Believers), as well as Belarusian and Ukrainian settlers of the 19th – early 20th centuries. For the fi rst time, the task was set to analyze the connection between specifi c phenomena of the sign-semantic space of traditional culture and the identity of the Russian and other East Slavic peoples of Siberia, taking into account their diversity in the 19th – the fi rst third of the 20th century, when the foundations of regional and ethno-cultural self-awareness were laid. The issue of the existence of a common Siberian identity (meaning that unites all Siberian administrative units, regions and territories) and the features of its formation, as well as options for visualizing the image of Siberia and “Siberianness” in the process of searching for one’s own identity, is comprehensively considered. For ethnographers, anthropologists, historians, culturologists, local historians, students and everyone who is interested in the culture and way of life of Russian and other East Slavic peoples living in Siberia.