The problems associated with the testing of equipment for treating surface runoff contaminated with heavy metals are assessed. The specifics of the heavy metals present in it and the features of processing were considered. The article presents the design of the developed full-scale bench for testing filter cartridges (in particular, FOPS^® filters), as well as the technique for modeling waste and natural waters contaminated with heavy metals on it. The study results reflecting the operational features of FOPS^® filters were presented.

The results of experimental studies on carbon nanomaterials production in the plasma of an arc discharge initiated in an open air were presented. The possibility of using waste carbide tools as a catalyst for obtaining quasi-two-dimensional carbon nanostructures by the proposed non-vacuum electric arc method was revealed. It was concluded that the process of synthesis of carbon nanostructures and electric arc processing of waste based on tungsten and cobalt are compatible.

The scientific results of the optimization of raw materials mixtures for the production of cement clinker with the involvement as a secondary raw material – technogenic waste of the enrichment of non-ferrous metal ores, which by their chemical composition are of interest as an iron-aluminum-silicate raw material component. It has been established that the use of non-ferrous metal ore enrichment waste in the raw material mixture in the form of secondary technogenic raw materials contributes to its utilization, reducing the specific fuel consumption during clinker firing by 5.76%, reducing the firing temperature by 50 °C and obtaining cement clinker that meets the requirements for chemical and mineralogical compositions according to GOST 31108-2016.

The problems of noise reduction arising during the operation of volumetric compressors are considered. A new noise suppressor is presented – a pulsation suppressor for volumetric compressors, which allows to effectively reduce noise and pressure pulsations at the output of a volumetric compressor both in a wide range of frequencies and at discrete frequencies in combination with a minimum pressure drop. A design model and an equivalent circuit of a noise suppressor – a pulsation suppressor are presented, and the design of its prototype is described. The results of tests of a noise suppressor – a pulsation suppressor for various structural designs are given. It is concluded that the use of a prototype noise suppressor – pulsation suppressor gives a high effect of reducing noise and gas pressure pulsations.

Comparative analysis performed on morphometric parameters of Galleria mellonella larvae grown on natural nutrient media with the addition of LDPE (low density polyethylene), HDPE (high density polyethylene) in various ratios 50/50, 60/40, 70/30, 80/20, 90/10. Levelling of different ratios of polymers was revealed while maintaining the viability of larvae. The content of LDPE microparticles in roughages of the digestive tract of larvae was identified by Fourier transform infrared spectroscopy showing partial digestion of synthetic polymers.

Instrumental methods of analysis were used to study sewage sludge formed during its processing by the enzyme-cavitation method for further water reuse. It was revealed that sewage sludge samples are multiphase porous aggregates containing both amorphous and crystalline components in their structure. X-ray phase analysis helped to determine the mineralogical composition, as well as the presence of fertilizing properties. Transmission electron microscopy showed that the studied sewage sludge has several scale structural levels of porosity from 5 nm to 6 μm. The sorption properties of sewage sludge, as well as the ability to absorb and retain water, were revealed.

It was emphasized that the assessment of water quality by comparing its characteristics with reference values inevitably leads to the analysis of the area of ambiguity by methods of mathematical statistics. The study results of the aquatic environment are correct if presented in a standard form with indication of confidence intervals and figures. To do this, it was proposed to build a non-parametric tolerance interval that takes into account both the margin and normalized errors of the assessed water quality indicators. Examples of analysis of water quality in natural water bodies of industrial region were provided. The article describes four options for a decisive function in assessing water quality (strict acceptance, strict rejection, non-strict acceptance, non-strict rejection), the choice of which in practice should be made by the water user or contracting parties on the basis of technical features and ecological situation.

A methodological approach has been developed to assess the level of environmental safety of the functioning of river water ecosystems in an urbanized area, taking into account the real problems characteristic of watercourses and hydraulically connected hydraulic structures. It is concluded that the application of this methodology will make it possible to conduct a comprehensive assessment of the current situation and develop an optimal list of measures aimed at improving the sustainability of river natural and technical systems located on the territory of cities.

The spatial variability of the content of heavy metals in the surface waters of the right tributaries of the river is presented Ural. The data of the calculation of the index of water pollution are presented, which make it possible to assess the water quality of the studied rivers by categories of pollution. The results of biotesting of water pollution using the seeds of cress Lepidium sativum L. and radish Raphanus sativus as a test objects are discussed.

The analysis of the qualitative composition of the waste water of the coal mining enterprise was carried out. As a result of monitoring studies, data on the composition of pollutants discharged into the water of small rivers were obtained. It is established that the feature of quarry waters is an increased content of suspended solids (inorganic dust) from drilling, blasting, overburden and mining operations; petroleum products from oil and fuel spills; nitrites and nitrates formed when using explosives; iron formed as a result of the oxidation of pyrite (often found in the host rocks), metal structures and parts of equipment and sulfates. The applied technology of wastewater treatment at a coal mine is considered, and its effectiveness is justified. It is shown that the main problem in the field of water resources protection is the lack of adapted technologies for deep wastewater treatment in relation to a specific enterprise. The ways of improving the technological level and quality of treatment of quarry wastewater are determined.

The results of monitoring studies of natural-anthropogenic and agricultural urban landscapes of the impact zones of the Tulachermet combine and the Kosogorsky Metallurgical Plant are presented. A survey of aerotechnogenic precipitation, soil and vegetation cover was carried out. It is shown that in the impact zones of metallurgical complexes, the predominant part of heavy metals enters the Earth's surface in solid-phase precipitation.