Content Of Organic Substances Research Articles

Solar pyrolysis tars treatment using oxidation processes – Efficiency and toxicity analysis

This paper presents oxidation and photocatalytic oxidation as the methods for elimination of toxic activity of biomass pyrolysis liquids subjected to the environment – water. With the increasing interest in biomass pyrolysis-derived fuels and chemicals, there is still a need for determining the environmental impact of unwanted leakage of the pyrolysis liquids to the environment via inappropriate handling or containers damage and proposing adequate solutions to solve it. Tars from solar pyrolysis of three biomass types (waste straw – WS, wood chips – WC, and dried sewage sludge – DSS) were treated using selected oxidation processes (ozonation – O3, photolysis – UV, and photocatalysis – UV-TiO2). The decomposition of organic substances present in the tars was investigated by changing the absorbance (Abs), total organic carbon (TOC), and phenol index (PI). Tar solutions before and after treatment were also submitted to an ecotoxicological assessment. It was determined that the tars organic substances content depended on the type of biomass subjected to solar pyrolysis. The highest concentration of organics was denoted in the liquid products from the solar pyrolysis of the sewage sludge. The decomposition of organic substances took place in the process of photocatalysis and ozonation, with higher effectiveness of the latter. The organic compounds present in the solar pyrolysis tar depend on the biomass feedstock. After 60 min of photocatalysis (TiO2 dose 1500 mg/L), phenolic compounds from tars coming from the solar pyrolysis of waste straw and wood chips were completely removed. In turn, the reduction in Abs and TOC was 37 and 19% for WS and 41 and 28% for WC, respectively. Abs in tars from the solar pyrolysis of sewage sludge in the photocatalysis process did not change, and the reduction of TOC and PI was 8 and 86%, respectively. However, the toxicity of post-process solutions requires attention. Tar solutions from the solar pyrolysis of wood chips after the photocatalysis process were non-toxic against bacteria, but tar solutions coming from the solar pyrolysis of waste straw and sewage sludge were low-toxic and toxic. Additionally, tars from the solar pyrolysis of sewage sludge after the photocatalysis process were highly toxic to crustaceans.

Geoecological Assessment of Resources of a Water Body for More Optimal Use

This paper presents a geoecological assessment of resources potentially available in or from shallow water bodies. It describes a case study as an example of how water bodies and coastal areas could be comprehensively analyzed, including microbiological testing, physical and chemical tests, testing water and bottom sediments for heavy metals, gamma spectrometry of soil samples, hydrological and hydroeconomic estimates. Experimental data is used to analyze the status of water bodies. Apparently, microbiological indicators are within the acceptable limits, and so are heavy metals. However, water sampled from Lake Oktyabrskoye has >10 times limit chromaticity and turbidity indicators, 10-11 times the limit chemical oxygen demand (COD). This indicates severe pollution and high concentration of organic substances. The presented approach to resource assessment could be of use when devising measures for nature-friendly restoration of water bodies.

Plant Growth on a Mediterranean Green Roof: A Pilot Study on Influence of Substrate Depth, Substrate Composition, and Type of Green Roof

Green roofs have been proposed as a significant method of “renaturing” the city, mitigating the urban heat island effect and controlling storm water movement. Plant growth on green roofs affects the environmental performance of the roof. Thus, it is important to examine which parameters influence this growth. Green roofs in the Mediterranean region, due to the climatic specificities of the area, have been a challenge. What types of plants are appropriate, how green roofs should be constructed and other related topics have concerned scientists in the recent years. The aim of this pilot study was to explore the growth of five plants—Sedum sediforme, Drosanthemum floribundum and Lampranthus spectabilis, Medicago arborea, and Lavandula angustifolia—on a pilot Mediterranean green roof in relation to substrate depth, organic content of substrate and type of green roof (open and modular). Data were analyzed using multiple regression with Analysis of Variance. The results indicated that substrate depth, type of green roof and substrate organic content are not significantly important parameters affecting the growth of plants and cannot predict plant performance by themselves. A main insight arising from this study is that plant communities and interspecies relations should be examined more closely in future green roof research as they may affect the impact of selected parameters on plant growth on Mediterranean green roofs. Furthermore, although the type of the green roof—open or modular—could not be directly associated with plant performance, it may be worth examining its impact on plant community performance in future studies.

The Influence of Organic and Conventional Cultivation Patterns on Physicochemical Property, Enzyme Activity and Microbial Community Characteristics of Paddy Soil

Cultivation patterns can cause soil structure alteration. However, few studies have clarified the influence of cultivation pattern and soil depth on soil. The purpose of this experiment was to study the community characteristics of soil microorganisms in the 0–10 cm and 10–20 cm layers beneath paddy fields under organic and conventional cultivation patterns, and reveal the response mechanism of microbial community to cultivation patterns through the correlation analysis of soil nutrient content, enzyme activity and microbial dominant phyla, so as to provide a theoretical basis for high-yield rice cultivation from the perspective of microorganisms. In this study, four types of soil organic cultivation topsoil (OF_S), organic cultivation undersoil (OF_X), conventional cultivation topsoil (CF_S) and conventional cultivation undersoil (CF_X) in paddy fields were collected for nutrient and enzyme activity determination, and composition spectrum analysis of soil microbial community diversity was performed using a high-throughput sequencing platform. The results revealed that organic cultivation increased the contents of alkali-hydrolyzable nitrogen, available phosphorus, available potassium and organic substances in both topsoil and undersoil as well as sucrase and urease activity in the undersoil. α diversity indicated that bacterial abundance in both topsoil and undersoil was organic > conventional cultivation; the microbial diversity index in the undersoil under organic cultivation technique was greater than that of conventional cultivation. A Venn diagram revealed that there was considerable difference in species between topsoil and undersoil under organic and conventional cultivation patterns. The composition of the community structure indicated that Proteobacteria, Acidobacteria, Chloroflexi and Bacteroidetes were the dominant phyla of bacterial communities in paddy fields. Ascomycota and Basidiomycota were the dominant phyla of the fungal community. Cluster analysis results indicated that soil depth of both patterns produced apparent clustering effects on microorganisms. Correlation analysis revealed that contents of various soil nutrients and enzyme activities affected the relative abundance of the dominant bacteria and fungi in varying degrees. Alkali-hydrolyzable nitrogen, available potassium and organic matters were significant factors affecting the dominant phyla of soil. The present study demonstrated that compared with conventional cultivation, organic cultivation improved soil physicochemical property, enhanced soil enzyme activity, and altered soil microbial diversity and bacterial abundance. Soil nutrients, enzyme activity and the microbial community of paddy fields interacted with each other and affected the soil structure together.

Development of soil-less substrates capable of degrading organic nitrogen into nitrate as in natural soils

Soil-less substrates are unable to catalyse nitrification because the addition of a high concentration of organic substances suppresses nitrification. We used a previously developed multiple parallel mineralization method, which enables the use of organic fertilizers in hydroponics, to support nitrification in soil-less substrates. In this method, microorganisms immobilized on porous substrates produced inorganic nitrate from organic substances, as in a natural soil. Phosphate and potassium ions were also released. Microorganisms produced nitrate from organic substances when immobilized on polyurethane resin, rockwool, vermiculite, oyster shell lime, and rice husk charcoal. The optimal amount of organic substance added daily to 100 mL of substrate held 6 mg of organic N. The optimal incubation temperature ranged from 25 to 42 °C. A high relative humidity (51% or higher) was more suitable than drier conditions (20%). The optimal amount of fish fertilizer added to the substrate was 6 mg organic N. The lower the C/N ratio of the organic substance, the better the result. Vegetable plants grew well on inoculated substrates but not on uninoculated substrates. These results show that soil-less substrates can be used to create artificial soils in which plants can be grown with the addition of organic fertilizer, as in a natural soil.

Flushing of Soils Highly Contaminated with Cd Using Various Washing Agents Derived from Sewage Sludge

The suitability of sewage-sludge derived washing agents (SS_WAs) (dissolved organic matter DOM; humic-like substances HLS; soluble humic substances SHS), was assessed for removing Cd from highly contaminated (300 mg/kg) sandy clay loam and clay. The soils were remediated via column flushing at two flow rates, 0.5 and 1.0 mL/min. The stability of the flow velocity (FV) depended on the type of SS_WA and decreased in the following order: DOM > HLS > SHS. Cd was most effectively removed during the first hours of flushing, and the process proceeded with a first-order kinetics. The overall process efficiency was higher at flow rate of 1.0 mL/min than at 0.5 mL/min and ranged from 65.7 (SHS) to 75.5% (DOM) for the sandy clay loam and from 64.7% (SHS) to 67.8% (DOM) for the clay. However, all SS_WAs at both flow rates removed the most mobile Cd fraction (F1) with an efficiency above 90%. Flushing improved soil characteristics in terms of the content of organic matter, humic substances and nutrients. Among all SS_WAs, DOM was the most suitable for remediation of highly Cd-contaminated soils due to high efficiency of Cd removal, the high stability of its FV during flushing and the simple manner of DOM recovery from sewage sludge.

Evaluation of organic load-related efficacy changes in antiseptic solutions used in hospitals.

In this study, it was aimed to evaluate the change in antimicrobial efficacy related to the presence of the organic load of four different antiseptic solutions that are frequently used in hospitals. Solutions of hydrogen peroxide, povidone-iodine, chlorhexidine digluconate, and ethyl alcohol were prepared, tested in terms of antimicrobial efficacy changes in the presence of organic substances, and evaluated according to EN 13727 and EN 13624 standards. Among the investigated solutions ethanol 70% solution showed the best results by providing a 5-log reduction on all test organisms without affecting by the type and concentration of organic substances. Solutions of hydrogen peroxide 3%, povidone-iodine 7.5%, and chlorhexidine digluconate 0.2% performed lower antimicrobial efficacy depending on the concentration of organic load. It is concluded that the antimicrobial efficacy of antiseptic solutions is significantly affected by the organic substances and thus the proper use of antiseptics has become important to achieve successful disinfection and prevention of antibacterial resistance.

ТЕНДЕНЦИИ ИЗМЕНЧИВОСТИ ХИМИЧЕСКОГО СОСТАВА И КАЧЕСТВА ВОДЫ ПРИТОКОВ НИЖНЕЙ ВОЛГИ С УЧЕТОМ АНТРОПОГЕННОГО ВОЗДЕЙСТВИЯ И КЛИМАТИЧЕСКИХ ИЗМЕНЕНИЙ

The regional features of transformation in the chemical composition of water in the Lower Volga tributaries and its main trends under anthropogenic impact and climatic variations are presented. Most trends for the principle ions (sulfates, carbonates, calcium and magnesium ions) are increasing, which may be a consequence of ongoing climate change. Moderate decreasing trends prevail in the concentrations of nutrients and organic substances in water. It was found that the trends in metal concentrations are multidirectional. All revealed statistically significant trends for iron and copper compounds are decreasing, and those for manganese are increasing. Based on the analysis of the identified trends in the chemical composition, the river ecosystems of the Lower Volga tributaries are classified into two categories: stable (“healthy”) and transformed (“transitioning”).

Еколого-геохімічна характеристика природних вод у межах впливу Добрівлянського газоконденсатного родовища (Передкарпаття)

A study of natural waters within the influence of the Dobrivlyany gas condensate field, located in the Dobryany and Dobrivlyany area village councils of the Stryi district of the Lviv Region of Ukraine, was conducted. The purpose of the work is to evaluate the geochemical indicators of natural waters based on our own research, to find out the role of natural and man-made factors in the formation of the chemical composition of waters. The objects of the research are surface waters and groundwaters within the influence of the Dobrivlyany gas condensate field. Research results. In the research area, as well as in the Bilche-Volytsia zone in general, there are unfavorable conditions for active water exchange and the formation of fresh infiltration waters, since the upper part of the geological section is characterized by clayey Neogene deposits. The depth of penetration of fresh hydrocarbonate-calcium waters here does not exceed 70 m. The small thickness of the zone of active water exchange is one of the indicators of difficult water exchange in the subsoil, therefore, favourable conditions for the preservation of hydrocarbon deposits. As a result of exploratory work, the Dobrivlyany gas condensate field was opened in 2016. During 2016–2019, 7 boreholes were drilled, and industrial gas inflows were received from horizons LD-9, LD-12, and N1kr+K2. In tectonic terms, the deposit is confined to the northwestern part of the Kosiv-Ugersko subzone of the Bilche-Volytsia zone of the Carpathian Foredeep. Observation of the macro component composition of groundwater from the wells of the Dobrivlyany gas condensate field indicates the stability of the hydrodynamic conditions of the deposit and, accordingly, the low variability of their geochemical characteristics. Direct hydrogeochemical zonation is clearly manifested in the increase in water mineralization with depth: for the LD-9 horizon at depths of 800–840 m, it varies within the range of 34.74–48.55 g/dm3, for LD-12 at depths of 995–1010 m – 33.82–73.70 g/dm3 and for N1kr+K2 at 1131–1158 m – 67.49–100.31 g/dm3. The content of Br and J doubles with depth. All waters are of the chloride-calcium type (according to Sulin), and genetic indicators vary within narrow limits (rNa/rCl – 0.82–0.91; Cl/Br – 216–315; rSO4 ∙ 100/rCl – 0.003–0.5) and indicate their thalassogenic sedimentogenic origin. The analysis of research results showed that underground waters belong to a single hydrodynamic system, and are characterized by the same type of water according to their chemical composition. According to the qualitative characteristics of groundwater from an ecological borehole and a well in the Dobrivlyany village remain clean and meets regulatory requirements for drinking water. At the same time, water from a well in Vivnya village is characterized by a high content of nitrates (2.28 maximum permissible concentration), which is caused by the location of the pig complex “Halychyna-Zakhid” LLC on the outskirts. Increased content of organic substances in the waters of two wells of the Railiv village was also established, in which the permanganate oxidizability reaches 1.08–1.24 maximum permissible concentration, and, according to Hygienic requirements for drinking water intended for human consumption, is unfit for consumption. The waters of the Kolodnytsia River are chloride-hydrocarbonate sodium-calcium (calcium-sodium) in composition, while the waters of the Stryi River and the Zhizhava River are calcium bicarbonate.

Influence of variety of soil-ground conditions of sandy soils (by the example of the Ust-Donetsk sandy massif) on the quality of the grape vine

The paper reveals the influence exerted on the development of post vitro grape mother plants and various microzones found on the Ust-Donetsk sand massif. The differences in the microzones were in the fertility level and a number of soil properties. The considerable influence provided by the growing conditions not only on the development of plants but also on the survival rate and life expectancy of mother bushes observed during the use of mother plants for 17 years has been noted. To ensure effective land management, a detailed site study and, depending on the differences identified, the use of precision farming techniques is required before laying out the parent plants. The reason for this is that sandy soils, in general, have a high degree of heterogeneity due to physical and chemical characteristics such as flowability, susceptibility to wind transport, low organic substance content, and cation exchange capacity.

Three-Stage Membrane Treatment of Wastewater from Biodiesel Production-Preliminary Research.

As biodiesel production as renewable fuel increases, so does the amount of wastewater resulting from this technology. Wastewater is generated during the so-called biodiesel washing, i.e., washing out glycerol and methanol with water. The purified biodiesel must meet international standards, such as EN 14214 or the American ASTM D6751 standard. To fully say that biodiesel technology is environmentally friendly, the amount of wastewater should be minimized. It is also desirable that the purified water can be recycled to the technology. For this purpose, wastewater pre-treated by flotation, during which mainly oils are removed, was subjected to three-stage membrane separation. For each of the stages, the membrane was selected and characterized in terms of its separation capacity and stream stability. Starting with microfiltration, which was mainly aimed at reducing turbidity, affects the permeate flux in the following steps. Then, ultrafiltration and nanofiltration membranes were selected. These membranes were aimed at reducing the concentration of inorganic and organic substances. Consequently the cascade was composed of: MF-0.45 µm, UF-150 kDa, and NF-characterized by an 80% degree of desalination. The final permeate has a salt concentration of less than 0.15 g/L and can be reused in biodiesel technology.

Response of marine microalgae Phaeodactylum tricornutum, Prorocentrum cordatum and Gyrodinium fissum to complex pollution of Sevastopol bays (Black Sea)

For the degrees of toxicity assessment within the Black Sea surface coastal waters near Sevastopol, laboratory experiments were performed on three marine microalgae species culture’s growth in water sampled on the three stations of the region from May to December 2020. The study has indicated, that in the majority of cases, insignificant inhibiting influences of the waters to diatom Phaeodactylum tricornutum Bohlin and insignificant stimulated effect to dinoflagellates Prorocentrum сordatum (Ostenfeld) J.D.Dodge and Gyrodinium fissum (Levander) Kofoid & Swezy were observed. Rarely this effect was characterized as chronic or subacute. The concentration levels of both stable and unstable forms of organic substances in the studied waters were estimated. The results of the testing of the water to determine its contamination using microalgae and analysis of the organic substances concentration levels in them, allowed the conclusion that the studied area should be classified as episodically polluted. Justification for the necessity to use several microalgae species of different taxonomic affiliation when performing marine water biotesting is provided in this study.

ANALYSIS AND TREATMENT OF WASTE WATER FROM FISH PROCESSING ENTERPRISES

A distinctive feature of waste water of fi sh processing enterprises is the high content of organic substances: COD - 620-3500 mg/L, BOD-220-2860 mg/L. The ratio of BOD:COD=0.68-0.83 in the waste water of fi sh processing enterprises shows a high potential for the use of biological treatment methods. Further study requires the removal of biogenic elements, because, for example, for a fi sh cannery, the ratio of BOD:N:P=100:3.79:1.08 and 100:4.77:0.57. This article presents the experience of design, construction, start-up and adjustment of sewage treatment facilities of a fi sh processing enterprise. For wastewater treatment, the following scheme was developed and manufactured by the ECOLOS company: a receiving well with a basket, a drum grate, a horizontal grease trap, an homogenizer, a reagent pressure fl otation unit, a membrane bioreactor, and ultraviolet disinfection. The quality of waste water at the outlet of the treatment facilities meets the requirements of the Normative- permissible discharge provided by LLC «Russkaya Treska».

Nutritive capability of anaerobically digested black water increases productivity of Tetradesmus obliquus: Domestic wastewater as an alternative nutrient resource

Domestic wastewater represents a potential source of nutrients, water and energy. In this study, Tetradesmus obliquus was grown in anaerobically digested black water (BW) to observe growth limitation factors and physiological performances of the algal cells. Supplementing BW with Fe2+, Mg2+, and Mn2+ allowed maximal growth and a significantly higher productivity (0.357 g DW L−1 d−1, compared to the control medium (CM) with 0.302 g DW L−1 d−1) (ANOVA F = 992, d.f. 4,10, p ≤ 0.05) was observed. Interestingly, compared to the CM, only 10% of chlorophyll a concentration was observed at such higher productivity but a two times higher number of resting spore cells (which showed accumulation of lipid and starch granules) were found. The existence of an about 1000 times higher concentration of organic substance in BW than in CM may facilitates a mixotrophic mode and became advantageous for the growth of T. obliquus.

Investigation of factors of the appearance of odor in river water at the water intake of Rostov-On-Don

The paper presents a study of quality of natural waters and water in a centralized water supply system during the period of an increase in the “Smell” indicator in the spring of 2021. The chemical and physical properties of water, the results of quality and quantity of studying the variety I phytoplankton in the most difficult period of deterioration in quality of river water. Low water and exceeding MPC concentrations of organic substances in river water. The Don River causes altered form odorant substance as evidenced by the results of determination in water 1,2,3- t rihlorbenzol and geosmin, hexachloroethane and aniline shown in operation. Barrier function of reagent treatment methods used at water treatment plants in the lower reaches of the river. The Don River, even when combined with carbonated water, is deficient in odor-producing substances.

Innovative desalination of geothermal wastewater supported by electricity generated from low-enthalpy geothermal resources

The integration of renewable energy generation with water treatment techniques, based on geothermal water and energy resources, represents a new and interesting research direction. This paper presents a model study aimed at evaluating the twofold utilisation of geothermal water potential: as an energy resource necessary for the desalination process and as a source of wastewater used in the desalination process. The key objective of this work is to critically evaluate the feasibility of integrating electricity generation and technological processes based on membrane techniques solely on the basis of the potential of low-enthalpy geothermal waters. The results of the use of two steps of BWRO on a semi-production scale showed a high quality of permeate in accordance with physical, chemical, microbiological, potential organic and toxic substance contents and also its radiological characteristics. With respect to the feasibility of implementing the organic Rankine cycle or the Kalina cycle, an analysis was carried out that focused on using geothermal water extracted in the temperature range of 80–95 °C. The mass flow rate of geothermal water directed to the power plant was assumed to be in the range 10–150 kg/s. The mineral content of the geothermal water used in the model was 3 g/L.

Bioindication of mercury pollution of the Amur River during the ice-covered period

The results of the layer-by-layer research of a river ice cores by using spectral and microbiological methods were presented. The impact of the mercury on sulfate-reducing bacteria activity from different layers of ice that had been sampled in March 2016 in the lower Amur River in Khabarovsk city was found. It was found that mercury concentration range of 0.0005-0.001 mg/l stimulated the sulfate-reducing bacteria activity, which were into the ice throughout the study area of the Amur River. To a large extent, this effect was typical for the ice that was sampled in the right bank of the Amur River near Khabarovsk city, where mercury pollution of the aquatic environment had been detected repeatedly. The activity of biogeochemical processes into the ice determined by high concentrations of organic substances, by the pollution of the aquatic environment with mercury during the ice cover formation, and by the abundance of cultivated heterotrophic and sulfate-reducing bacteria. During the ice drift and ice melting, the secondary pollution with toxic substances of various genesis of the aquatic environment occurs, which can have a negative impact on a hydrobionts.

The design of multi-stage open-loop hollow fiber membrane contactor and its application in ammonia capture from hydrolyzed human urine

Hollow fiber membrane contactor (HFMC) is a promising technology for removing or recovering wastewaters' volatile components. Developing a rational design method is very important for guiding its further application. In this study, we proposed a method to design the multi-stage open-loop hollow fiber membrane contactor (HFMC) employing shell-side influent. In addition, a three-stage HFMC was designed to capture ammonia from real hydrolyzed human urine. A continuous 1344 h performance was conducted. The results showed that the experimental effluent total ammonium nitrogen (TAN) concentration and ammonia mass transfer coefficient matched the predicted results well, which indicated that the design method was feasible and accurate. The three-stage HFMC showed excellent ammonia capture capacity with a TAN recovery efficiency of 93.29%, and the final effluent TAN concentration was 30.98±14.70 mg/L which met our design requirement (lower than 50 mg/L). More than 98.92% of the inorganic ions and 96.85% of the organic matter were retained in the effluent. The stripping solution after ammonia capture was the high-purity ammonium sulfate solution with low concentration of small molecular weight hydrophilic organic substances. The inorganic and organic membrane fouling was mild and randomly distributed. The inorganic membrane fouling was attributed to the deposition of calcium-, magnesium-, phosphate-related inorganic compounds, while the organic membrane fouling was mainly protein and carbohydrate. After the ammonia capture process, the surface hydrophobicity and pore properties of the membranes had no significant changes. These results demonstrated that the multi-stage open-loop HFMC could be a potential alternative for ammonia recovery from the high concentration of ammonium nitrogen wastewater.

Correlation between chemical composition and 90Sr concentrations in groundwater of the Chornobyl NPP industrial site

The volumetric activity of the divalent 90Sr ion in groundwater at the Chornobyl NPP industrial site ranges from 1 to 2 to 400–3800 Bq/l. The increase in groundwater radionuclides concentrations is associated with the reduced sorption properties of local sediments, which affect the migration capacity of radionuclides in the environment. The decrease of the 90Sr sorption properties of sediments is caused by changes in the chemical composition of groundwater. A new statistical method has been performed. Method based on the Monte Carlo method in order to evaluate the correlations between the 90Sr volumetric activity and the groundwater chemical composition components. Simulation results using this method suggest a correlation between the volumetric activity of 90Sr, the concentrations cations, the pH, and the oxidation index (organic contents). A direct correlation was established between the volumetric activity of 90Sr, Ca2+ concentrations and the pH of groundwater in the range from 7 to 12.4. It was revealed that the concentrations of Na+ and K+ do not affect the conditions of 90Sr migration with groundwater. There is an inverse correlation between the concentration of 90Sr and the oxidation index, which is an indirect indicator of the organic substances content in water. Thus, the presence of organic substances in the groundwater effectively promotes sorption of 90Sr. The proposed method of geochemical statistics enables a quantitative assessment of groundwater monitoring results.

CYCLES OF SOLAR ACTIVITY AS A BASIS FOR FORECASTING THE QUALITY OF DNIEPER WATER

One of the main features of the quality of the Dnieper water is the content of natural organic substances which determine the water oxidizability and color indexes. A special problem is that organic substances are poorly removed by water treatment plants. A significant problem in the operation of water treatment plants is the unpredictability of annual changes in the quality of Dnieper water, which complicates logistics management, for example, the supply of reagents. Many years of experience related to the Dnieper water supply station in Kyiv (DnWS) have led to the hypothesis that these changes are in some way related to the cycles of solar activity.
 The purpose of this work is to test this hypothesis to substantiate the possibility of predicting the quality of Dnieper water depending on the action of such a global factor as solar activity. The work was performed by statistical methods using 60-year results of Dnieper water analyzes provided by the DnWS laboratory, as well as Wolf numbers (Sunspot Numbers) provided for free use by the Royal Observatory of Belgium. The influence of solar activity on the quality indicators of Dnieper water, especially in its peak and post-peak periods, has been statistically confirmed. The interaction of biological and physicochemical parameters as factors influencing water quality is shown.
 Conclusions. As a result of the construction of six reservoirs in 1931-1976, the Dnieper from the river actually turned into a network of water bodies. Now these reservoirs are a kind of reactors in which water is treated by electromagnetic solar radiation, which leads to the cyclic transformation of phytoplankton and natural organic matter. Taking into account the cycles of solar activity, the logistical planning of the operation of water treatment facilities receives an independent "base", changes in which can be predicted with some reliability for years to come.