Water and water purification technologies

Scientific and technical news

PLASMA ARC WATER TREATMENT

S. V. Petrov1, Masato Homma2, D. I. Rubets1, O. N. Tereshchenko3, S. G. Bondarenko3

1 – The Gas Institute of NAS ofUkraine,Kiev, 2 – Global Energy Trade Co. Ltd,Tokyo,

3 –NationalTechnicalUniversityofUkraine”KPI”,Kiev

e-mail: vizana@voliacable.com

In the article we consider the plasma-chemical method for cleaning water of radionuclides and organic compounds after hydroseparation.    We analyze the main fields of use of electric-discharge technology for cleaning and decontamination of water. We define the main factors of plasma originating from electric discharge in bubble medium, and analyze their impact on the process of cleaning and decontamination of water. Therein we provide the description of plasma arc water treatment facility.    We consider hydroseparation method for restoration of soils contaminated with radionuclides.

We set forward the idea of combined methods, the main of which is plasma synthesis of finely-divided selective sorbent with simultaneous sorption and codeposition of radionuclides.

Whereby the chemical composition and morphology of nanoparticles (sorbents) are modified by electrode material. We present information on basic oxidizers synthesized in plasma, and analyze conditions of oxidation reactions taking place in the course of water treatment.

In this work, for the purpose of decontamination of liquid radioactive waste of caesium radionuclides, we used finely-divided ferrocyanide compositional sorbents produced via precipitation of ferrocyanide of the corresponding metal in the presence of finely-divided calcium carbonate and strontium synthesized in the zone of plasma treatment. We conducted tests on plasma codeposition of the radionuclides Cs-137 and Sr-90, as well as on purifying waters of organic compounds after hydroseparation of soils. The results proved high work efficiency of plasma-chemical treatment facility.

Key words: water treatment, plasma-chemical method, hydroseparation, active compounds.

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06.04.2016 at 7:00 pm

WATER DEFERRIZATION BY AXISYMMETRIC FOCUSED MAGNETIC FIELD

O.Terentiev, A.Vorfolomeiev

NationalTechnicalUniversityofUkraine”Kyiv Polytechnical Institute”

e-mail: o.terentiev@kpi.ua, a.vorfolomeiev@kpi.ua

The research considers the influence of permanent axisymmetric focused magnetic field on iron impurities in the water. The key attention is provided to determining (from experimental results) of mathematical model of water deferrization process by magnetic device. The deferrization efficiency has been chosen as the parameter of optimization, and the water flow rate and the part of waste – as the main factors of the experiment for research of water purification by axisymmetric focused magnetic field. During the experiment the total iron in water was reduced from 1.10 to   0.28 mg/dm3 and from 0.62 to 0.23 mg/dm3, turbidity – from 5.91 to 0.88 mg/dm3. Determined regression model of efficiency of water deferrization by focused axisymmetric magnetic field is adequate to Fisher’s F-test at the flow rate 0,14-0,40 m/s and the part of waste 0,10-0,35. The difference between regression curves and the experimental points is 2.57 %. To calculate the maximal effectiveness of water deferrization the regression model was reduced to canonical form, and additionally the regression equation was solved by iteration. Thus the maximal efficiency of water deferrization by magnetic device was 0.777 at the flow rate 0.31 m/s and the part of         waste 0.10.

Keywords: water deferrization, magnetic field, efficiency of purification, model.

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06.04.2016 at 6:34 pm

MODERN MICROBIOLOGICAL TESTS AS A BASIS FOR ENVIRONMENTAL SAFETY AND RESOURCE SAVING IN WATER DISINFECTION TECHNOLOGIES

S.L. Vasilenko, I.V. Korinko, E.E. Maximova

Municipal enterprise “Kharkovvodokanal”, Kharkove, Ukraine

e-mail: texvater@rambler.ru, korinko@aqua.kharkov.ua, emaximova@list.ru

This paper provides analysis of drinking water chlorination before its supply to water lines. It shows that representative system of microbiological water quality control at pumping stations and water columns enables maintenance of allowed percent of nonstandard samples at the rated level with reduction of chlorine application. This greatly reduces economic effect and provides environmental safety of municipal water supply systems and drinking water quality as of microbiological indices. This approach is applied at disinfection of drinking water of Kharkiv city (Ukraine).

Key words: drinking water, disinfection, chlorine, resource-saving.

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06.04.2016 at 6:28 pm

THE ESTIMATION OF WATER QUALITY DNIPER AND DESNA IN LARGE WATER SUPPLY POINTS

І.S. Yezlovetska, I.N. Lavrenchuk

A.V. Dumansky Institute of Colloid Chemistry and Water Chemistry of NAS ofUkraine,

PAO «АК «Кyivvоdоkаnаl»,Kyiv,Ukraine

The modern of our country classification conception and standardization of water sources quality for drinking water supply are tested by example of Kyiv areas of Dniper and Desna. This conception is based on three approaches: ecological, hygienic and technological. The specific character of water quality formation is considered in summer-autumn low water for middle by water content of hydrological period. The enumeration of index, which are certain necessary for the water quality estimation, is defined. It includes the blocks of organoleptic, general sanitary chemical, hydrobiological, microbiological, parasitological, radiation safety and toxicological indexes. First the estimation of water quality of chosen drinking water surface source for Dnieper and Desna water supply point near Kyiv is done according to hygienic and ecological criteria. The list of priority indexes of water quality, which requires the immediate attention under water treatment, is established. It is defined that the coloration, content of organic and biogenic substances, dissolved oxygen, рН, abundance and biomass of phytoplankton, microbiological and some of toxicological indexes refer to the same.

Results of carried out studies concerning estimation of Dnieper and Desna water quality in the district of water supply point of Kyiv can be used for development of measures concerning increase of technological operation efficiency on working constructions of Dnieper and Desna water supply stations.

Keywords: drinking water supply, water source quality, hygienic and ecological criteria, priority indexes.

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06.04.2016 at 6:19 pm

ELECTRICAL CONDUCTIVITY OF AQUEOUS SOLUTIONS AND ELECTROLYTIC DISSOCIATION

A. Zapolskii

ZhytomyrNationalAgroecologicalUniversity

е-mail: zak-38@ukr.net

A new theory of electrolytic dissociation and proton-electron conductivity of aqueous solutions was proposed. It supposed to be alternative to the theory of electrolytic dissociation S. Arrhenius and ionic conductivity. In liquid state molecules of water are associated into the clusters, forming fractal cluster-clathrate structures. Number of water molecules in the cluster is not precisely determined. Obviously, their number in the cluster is variable, which depends on the temperature of the aqueous system and other factors that determine the state of the aqueous system.

Electrical conductivity and ionization of the water system components are determined by the proton-electron interaction of water clusters with each other and with dissolved and/or suspended solids in the water system. Also this parameters are strongly affected by various physical-mechanical, physical and physicochemical effects, such as change of the hydrodynamic regime of moving water, mechanical and physical factors: pressure, temperature change, sound, magnetic and electric fields, UV radiation, dissolved and suspended substances (silicates, aluminum silicates, dissolved oxygen, carbon oxide (IV), bicarbonates, calcium, magnesium, iron, etc).

The dissociation of the electrolytes in the aqueous solution not occurs spontaneously. It is carried out under the influence of chemical reactions. Therefore, in an aqueous solution free ions (cations and anions) do not exist.

Keywords: electrical conductivity, electrolytic dissociation, fractal cluster-clathrate structures.

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06.04.2016 at 6:10 pm

THE EFFECT OF THE pH ON THE ABSORPTION OF HEXAVALENT CHROMIUM IONS BY HYBRID ADSORBENTS BASED ON TITANIUM OXYHYDRATE AND ORGANIC ANIONITE

T.V. Maltseva 1, A.V. Palchik 1, T.V. Yatsenko 1, S.L. Vasilyuk 1, V.O. Shablovski 2

1 – Vernadsky Institute of general and inorganic chemistry NAS Ukraine,Kiev,Ukraine

2 – Research Institute for Physical-Chemical Problems of theBelarusianStateUniversity,

Minsk, Belarus

e-mail: maltseva@ionc.kiev.ua

Studied the absorption of hexavalent chromium ions by hybrid ion exchange materials synthesized from 0.1-1.0 mM K2Cr2O7 solution without changing the acidity of solutions and with adding a solution of nitric acid to the initial pH = 2.4-2.7.For hybrid materials containing ~ 7, 24 and 36% by weight of titanium hydroxide, changing absorption capacity of components relative to hexavalent chromium ions, in particular, the distribution coefficient is according to the rule of additivity.With the addition of nitric acid pH = 2.4 in the initial solutions K2Cr2O7 for a hybrid sorbent containing ~ 36% by weight of titanium hydroxide, found a non-additive increase in the value of the distribution coefficient of hexavalent chromium ions. The degree of non-additivity of absorption capacity the ion exchange material increases significantly as the concentration of the solution.

Keywords: hybrid materials, titanium hydroxide, chromium ions, distribution coefficient, additivity.

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06.04.2016 at 6:04 pm