Manganese pollution of drinking water extracted from the terrace of Vacha River

The presented study is aimed towards determining the reasons for manganese pollution of drinking water extracted from the terrace of Vacha River. The results show that this is due to the seepage of from the artificial lake, formed after the construction of a small hydropower plant. Another possible reason is the natural accumulation in the upper parts of the river terrace of poorly soluble in water manganese compounds that turn into soluble ones as a result of changes in the redox environment, which take place in the conditions of very intensive groundwater extraction.

Estimation of the effectiveness of ozone use in the purification of heavily contaminated water supply sources

Источники питьевого водоснабжения (реки Великая, Волга, Вычегда, Которосль, Лименда, Солда, Северная Двина, Томь и Тура) характеризуются повышенным содержанием органических соединений природного и антропогенного происхождения. Традиционная технология двухступенчатого осветления воды коагулированием в данном случае по своей эффективности не соответствует качеству воды источника, в результате по некоторым показателям питьевая вода периодически не отвечает современным требованиям стандарта. Особенно сложно обеспечивать в питьевой воде предельно допустимые концентрации органических веществ, а также соединений железа, марганца и остаточного алюминия. Для очистки такой воды были изучены дополнительные методы окисления и сорбции. Результаты исследований показали, что предварительное озонирование речной воды и (или) постозонирование воды после фильтров станции водоподготовки повышают эффективность очистки по цветности, мутности, удалению соединений железа и марганца, уменьшают концентрацию остаточного алюминия, улучшают органолептические показатели. Сорбционная очистка с озонированием существенно улучшает качество очищенной воды и позволяет обеспечить допустимый уровень содержания органических загрязнителей в питьевой воде. Sources of drinking water supply (the Velikaia, Volga, Vychegda, Kotorosl’, Limenda, Solda, Severnaia Dvina, Tom’ and Tura rivers) are characterized by increased concentrations of organic compounds of natural and anthropogenic origin. The traditional technology of two-stage water clarification by coagulation in terms of the efficiency, in this case, is not applicable to the quality of the source water; as a result, by some indicators, drinking water periodically does not meet the current standard requirements. It is especially difficult to ensure the permissible maximum concentrations of organic substances in drinking water, as well as of compounds of iron, manganese and residual aluminum. To provide for the purification of such water, additional oxidation and sorption methods have been studied. The research results showed that preliminary ozonation of river water and (or) post-ozonation of water after filtration at a water treatment plant provide for increasing the efficiency of purification in terms of color, turbidity, removal of iron and manganese compounds; for reducing the concentration of residual aluminum, and improving the organoleptic characteristics. Sorption with ozonation significantly improves the quality of treated water and allows to ensure the permissible level of organic pollutants in drinking water.

Justification of modernization of groundwater treatment station

The main contaminants of groundwater are iron and manganese compounds, increased hardness, which are removed at groundwater conditioning stations. The article reviews the existing station that was built according to a conventional design and uses the method of simplified aeration with the following filtration through high-silica sand. Assessment of the technical condition of the station showed that the elements of the building are limited to work The filters are in poor condition, some of the filters are out of service, there are concrete corrosion, destruction of finishing layers in filters’ building, internal and external corrosion of metallic pipelines and valves, which depend on he quality of transported water. Wear of the technological pipelines is over 80%. Analysis of the efficiency of the station showed that it operates at 50% capacity and at the same time does not provide standards for the hardness of drinking water. Water consumption for the station’s own needs is 1.5 times higher than it was designed. There are no processing and reusing facilities for flushing water. Results of the technical and technological inspection of the station showed that there is a need for immediate modernization of the station including the improvement of the groundwater purification technology and bringing he quality to the standards for drinking water.

PECULIARITIES OF ABSORPTION OF SULFUR DIOXIDE AND NITROGEN OXIDE IN SUSPENSIONS AND SOLUTIONS OF MANGANESE COMPOUNDS

It is proposed to use manganese compounds to reduce emissions of sulfur and nitrogen oxides, large deposits of which are in Ukraine. The results of experimental studies of the binding of sulfur dioxide and potassium permanganate of nitric oxide in water by manganese oxide are presented. In the experiments, the model gas in the form of small bubbles was passed through the reactor with liquid. Heat and mass transfer processes between the gas and liquid phases occurred on the bubble surface. The gas-liquid contact time is the bubble rise time. The absorption reactions take place in the liquid phase. Complete absorption of sulfur dioxide takes place in an acidic environment, provided that the molar ratio MnO2 / SO2 is not less than 2. The reaction product is manganese sulfate, which is a useful product. The maximum absorption of nitrogen oxide is achieved at a molar ratio of KMnO4 / NO not less than 5. The reaction forms a precipitate of manganese oxide, which can later be used in the desulfurization process. Bibl. 12, fig. 6, tab. 3.

The effect of manganese(II) excess on growth and antioxidant status of barley seedlings

Manganese belongs to the group of heavy metals, which at high concentrations can have a negative effect on plant development. Typical soils of the Kirov region are acid podzolic and sod-podzolic soils, which are characterized by high content of manganese compounds available for plants. Studied was the effect of manganese(II) ions at the concentrations of 30.0, 60.0 and 90.0 mg/l on the growth and antioxidant activity (AOA) of the superoxide dismutase enzyme (SOD) in the organs of 7 and 14-day-old barley plants grown in aquatic culture. Varieties and forms of barley 346-09, 29-11, Farmer 198-12, Forward and Bionik, resistant to acidic soils (Al3 +, H+) served as objects for the research; Belgorodskij 100 variety was used as standard. When manganese was added to the solution for growing, a decrease in root length and an increase in AOA of SOD in plant roots were noted. It was concluded that increased concentrations of manganese had an effect on the morphometric parameters and on AOA SOD of barley seedlings. It has been established that increasing the dose of manganese in the solution for growing leads to a decrease in the length of the roots. AOA SOD varied in different organs of plants of some varieties, and its more significant change in the experiment compared with the control was revealed in the roots. Judging by morphometric indicators, the Belgorodskij 100 variety was the least resistant to Mn2+ ionic toxicity, the root length of which in the control was 15.7±0.4 cm, and in the experiment 13.2±0.3; 12.2±0.1; 11.5±0.3 cm in accordance with the dose of manganese 30, 60 and 90 mg / l. According to the level of AOA SOD, the most sensitive variety was Farmer 198-12, its change of AOA SOD in the roots (% of control) was 158.8; 167.2 and 169.4% in accordance with the dose of manganese 30.0; 60.0 and 90.0 mg / l (AOA SOD in the control was 52.4±0.4%; in the experiment 83.2±2.2; 87.6±2.0 and 88.7±0.6, respectively), and in the shoots ˗ 121.0; 128.3 and 125.6 %, respectively (66.7±7.9 % in the control and 80.7±0.5; 85.6±1.4; 83.8±0.6 % in the experiment in accordance with the dose of Mn 2+).