The model of a traditional vortex apparatus in a program complex is constructed and constructive changes of such apparatuses are proposed. The adequacy of the constructed model in comparison with the existing traditional vortex apparatus is evaluated. The conclusion about the important influence of the design solution on the efficiency of dust collection is made. It is revealed that due to insignificant changes in the angle of inclination of the gas stream inlet, there is an increase in the fractional efficiency, approximately by 4–7 %.

The conditions for increasing the energy efficiency of the process of obtaining the dispersed gas phase in electroflotators by optimizing the parameters of the electrode unit operation are studied. As an efficiency criterion, the specific gas yield representing the volumetric flow rate of emitted gases per unit of current strength is taken. Studies on the model of electroflotation cell with a capacity of 5 dm³ were carried out. The influence on the specific gas yield of the ratio of densities of anodic and cathodic currents in the range of 52–2500 A/m² was analyzed. It is established that the basis of gas release is represented by the cathodic process of molecular hydrogen formation, while the anodic process of oxygen formation can be complicated by electrochemical reactions with anions included in the composition of wastewater. It is revealed that the highest specific gas yield, which is up to 95 % of the theoretically possible, is achieved at the ratio of active surfaces of anodes and cathodes equal to 2:1, respectively, in the range of anodic current density from 150 to 250 A/m² with cathodic current density from 300 to 500 A/m². It is concluded that the application of the research results allows increasing the energy efficiency of the process of gas dispersion generation, reducing the dimensions of the electrode block, optimizing the structural solutions in the design of electroflotators.

The possibilities of using activated carbons (ACs) from vegetable biomass as electrode materials of supercapacitors based on organic electrolytes and ionic liquids are considered. It is noted that the ACs used in supercapacitors should have a number of characteristics, the most fundamental of which are textural: specific surface area by BET not less than ~1500 m²/g and the presence of a high proportion of mesopores. Studies on the use of two types of vegetable wastes (rice husk and pine nut shell), as well as two methods of chemical activation (alkaline/carbonate and phosphoric acid) have been carried out, as a result of which ACs with the required textural characteristics were obtained.

Comprehensive studies on agrochemical, toxicological and microbiological evaluation of composts from solid municipal waste (SMW) (organomineral fraction less than 10 mm) produced at the Novy Svet-EKO landfill (Leningrad region) were carried out. The potential agronomic value of composts as fertile soil for plant growth in terms of the content of basic nutrients and acid-base properties was established. The degree of organic matter stabilization and readiness of composts for safe use were determined by the dynamics of their microbial respiration, indicators of nitrogen cycle processes and toxicity. The conclusion about the favorable agrochemical properties of SMW composts and the increased content of basic elements of plant nutrition (N, P, K) in them was made. Toxicological indicators of composts were studied, which allowed to assign them to IV–V classes of hazard (low-hazard and practically non-hazardous) in accordance with the MNR Order No. 536.

Comprehensive studies of physicochemical properties, including textural and morphological, of iron-containing waste from the landfill of the Zavolzhsky Chemical Plant (Ivanovo region, Russia) were carried out. The data on changes in elemental and phase composition of red mud depending on the depth of occurrence and time of storage at the landfill were obtained. Methods of primary treatment of iron-containing wastes of Zavolzhsky Chemical Plant to obtain iron-containing intermediates for synthesis of catalysts were proposed. Morphology and distribution of elements on the surface of red mud after its thermal treatment at different temperatures, as well as porosity of iron-containing wastes after their thermal treatment in air oxygen environment were studied. The use of iron-containing wastes from Zavolzhsky Chemical Plant as a semi-product of iron-containing catalysts and chemisorbents for deep processing of process gases is recommended.

The results of the study of the content of heavy metals and as in the soils of the dump of the Gorlovskoye anthracite deposit, depending on the main chemical and physical properties are presented. Soil acidity, granulometric composition, as well as the content of nitrogen and carbon were studied. The dependence of metal content in the analyzed embryozem on the pH value and the amount of organic carbon was established. It is concluded that the content of heavy metals and their mobile forms in soils is below the maximum permissible values and corresponds to background levels, except for As, whose gross concentration exceeds the MAC and background value.

Recommendations for the establishment of standards for the content of petroleum products in the soils of the region have been developed. Experiments have been carried out to determine the permissible residual content of oil and its transformation products in soils for podzolic, predominantly deep podzolic soil, sod-podzolic soil, predominantly shallow and shallow podzolic soil, sod-podzolic illuvial-iron soil, chernozem podzolized soil and floodplain soil. Chronic phytotoxicity was assessed by the reaction of four species of terrestrial plants: soft wheat, cress, hybrid spruce and common pine. An aqueous extract of petroleum contaminated soils was tested using test subjects Chlorella Vulgaris and Daphnia Crustacea. Quantitative indicators of permissible concentration of hydrocarbons in soils after reclamation for agricultural and forest lands in Perm Krai were obtained.

The use of sodium ferrate as a disinfectant for industrial wastewater from such groups of pathogenic microorganisms as generalized coliform bacteria (GCB), bacteria of the genus Salmonella, Enterococcaceae and Staphylococcaceae is considered. Several types of wastewater were studied to investigate in more depth the possibility of using sodium ferrate for disinfection. It is shown that the use of sodium ferrate with the addition of 2, 3.5 and 5 vol. % of the current volume of the investigated wastewater samples has a high inactivation of the investigated pathogenic microflora. The most effective concentration for almost complete disinfection of real wastewater from the meat industry for all four microbiological indicators was identified: 5 vol. %.

The current state of affairs with handling and disposal of solid municipal wastes (SMW) in Russia is considered. It is shown that the greatest environmental danger is posed by toxic leachate and so-called landfill gas formed at landfills and dump sites as a result of natural decomposition of organic components of waste. The negative impact of landfill gas on the environment was emphasized. It is recommended to create a highly effective system of degassing of SMW landfills and dump sites in accordance with environmental legislation. The most productive measures on degassing of SMW landfills and dump sites are noticed, consisting in introduction of technology of extraction, preparation and energy use of landfill gas.

On the basis of a detailed comparison of the boundaries of disturbed areas with the boundaries of land allotments for infrastructure facilities, the share of exceeding the permissible mechanical impact on the soil and vegetation cover for a representative sample of oil and gas fields located in the natural conditions of the northern taiga was estimated. It was found that the total share of land withdrawal averages 7.2 %, while the median share of exceeding the limits of regulated impact relative to the land withdrawal area is 9.3 %. The retrospective analysis of vegetation dynamics within the disturbed areas was carried out, which showed that in 9-11 years of industrial development of deposits the values of vegetation index NDVI decrease by 40 %, but in 24–26 years NDVI starts to increase steadily, which confirms a clear tendency of natural vegetation recovery in conditions of reduced intensity of anthropogenic impact. It is concluded that it is necessary to carry out regular remote monitoring of land use in the conditions of oil and gas infrastructure expansion in the north of Western Siberia.

The possibility of using the parameter of test-crop germination to determine soil contamination by petroleum hydrocarbons in areas with low anthropogenic load is shown. The significance of the choice of a test-crop sensitive to hydrocarbon pollution and quality control of seed material is noted. The possibility of using the parameter of oat germination to determine soil pollution by petroleum hydrocarbons in the course of a model experiment consisting in germination of test-crop seeds in soils with given concentrations of pollutants has been evaluated. It is concluded that the parameter of test-crop germination can be used to establish low levels of soil contamination with hydrocarbons.