Water and water purification technologies

Scientific and technical news

THE NEW TEST OBJECT FOR EVALUATING THE QUALITY OF DISINFECTED WATER

UDC 628.166 + 582.288

O. S. Bolgova, M. N. Saprykina, V. V. Goncharuk

Dumansky Institute of colloid chemistry and water chemistry of NAS of Ukraine, Kiev, Ukraine

e-mail: saprikinam@yandex.ua

Monitoring of water sources and tap water in Kiev was conducted. It was found that the fungi of Candida genus are ubiquitous. It is shown that these microscopic fungi are more resistant to various disinfectants compared to sanitary indicative microorganism Escherichia coli. A new test object for evaluating the quality of purified water is proposed.

Keywords: water, monitoring, disinfection methods, test object for evaluating the quality of disinfected water.

Cite this article as: Bolgova, O.S., Saprykina, M.N., Goncharuk, V.V. WPT STN (2016) 20:3. | Download (PDF)

04.04.2017 at 8:34 pm

CHARACTERIZATION OF SORPTION MATERIALS CONTAINING OXIDES OF MULTIVALENT METALS FOR USE IN PROCESSES OF LITHIUM EXTRACTION FROM SALT SOLUTIONS

UDC 544.726.3

M. A. Chaban1, A. V. Pal’chik1, L. M. Rozhdestvenskaya1, S. L. Vasilyuk1, V. M. Linkov2

1Vernadsky Institute of general and inorganic chemistry of the Ukrainian National Academy of Sciences, Kiev, Ukraine
2University of the Western Cape, Bellville, South Africa

e-mail: mary.chaban@gmail.com

Since lithium is one of the most popular materials for the electronics industry, it is of interest to consider alternative sources of its receipt. The article analyzes the main sources of lithium production, global stocks and the dynamics of its production. We have considered the possibility of obtaining lithium from sea water by sorption method. The comparative characteristic of sorption materials based on the multivalent metal oxides was conducted, their structure parameters were determined. By method of X-ray analysis structure of the sorbents was studied. It is shown that the titanium-manganese sorbent is composite material consisting of particles of TiO2, rutile coated with amorphous MnO2. By electron paramagnetic resonance method valence states of manganese component in the sorbent structure were set. Adsorption isotherms from lithium solutions simulating sea water were obtained. The effect of modification of sorption materials by ion application was studied. It is shown that the highest sorption capacity to Li+ ions corresponds to titanium-manganese sorbent.

Keywords: lithium, composite materials, titanium dioxide, titanium-manganese sorbent, ion application.

Cite this article as: Chaban, M.A., Pal’chik, A.V., Rozhdestvenskaya, L.M., Vasilyuk, S.L., Linkov, V.M. WPT STN (2016) 20:8. | Download (PDF)

04.04.2017 at 8:18 pm

BARBOTINE ACTIVATING SOLUTIONS AND THE ROLE OF THIS PHENOMENON IN NATURAL AND TECHNOLOGICAL PROCESSES

UDC 544.353:544.7:550.461

S. V. Kushnir, M. V. Kost

Institute of Geology and Geochemistry of Combustible Minerals, Lviv, Ukraine

e-mail: M_Kost_2007@ukr.net

The possible molecular mechanisms of water structuring and between the surfaces of gas/water in the solutions are considered. It was shown that barbotage activation (BA) occurs by increasing the structural temperature of water and causes increasing of chemical activity of H2O and dissolved oxygen. It is established that BA has quasi equilibrium character. Therefore external influences on the lines of changes of pH and Eh characteristic peaks or steps appear that can be used to investigate the interaction of solutions with different solid materials. The proposed model of structural transformation may explain why negatively charged bubbles of gas form positively charged droplets of sea spray.

Keywords: salt solutions, barbotage of passive gases, structural temperature of water, structural activation, structural quasi equilibrium, chemical resistance of metals.

Cite this article as: Kushnir, S.V., Kost, M.V. WPT STN (2016) 20:22. | Download (PDF)

04.04.2017 at 7:48 pm

BARBOTAGE CHEMICAL EFFECTS: THEIR TYPES, MECHANISMS OF OCCURRENCE AND GEOCHEMICAL MANIFESTATIONS

UDC 550.4:541.183

S. V. Kushnir, M. V. Kost, R. P. Kozak

Institute of Geology and Geochemistry of Combustible Minerals, Lviv, Ukraine

e-mail: M_Kost_2007@ukr.net

The changes of pH and Eh in water and aqueous NaCl – solutions at 20 °C during the transmission of pure gases (N2, O2, air, CO22) in different modes of barbotage are experimentally investigated. The results are analyzed taking into account modern notions of the structure of liquid water and its surface (interface). Generally, the barbotage process consists of two stages: I – the first 10 minutes with the rapid increasing in pH and decreasing in Eh due to leaching of dissolved CO2 and O2; II – up to 2-3 hours when Eh continues to decrease slowly, but pH can increase (alkaline BCE) or decrease (acid BCE), indicating the acidic nature of gas/water surface and aerosols produced during barbotage. Special experiments on the magnetic stirrer showed that noticeable changes in pH and Eh begin only after the transition from laminar regime of mixing to turbulent, which leads to a significant increasing of the structural temperature of water and a corresponding reduction in the solubility of oxygen and Eh values. This is the main reason for the changes at the first step of barbotage, which can be called as the turbulent BCE. We must highlight the differentiation of ions during barbotage in mixed salt solutions. To explain this phenomenon of ion BCE, the hypothesis of neutral ion pairs has been proposed and substantiated, which satisfactorily explains the genesis and properties of marine aerosols.

Keywords: water, solutions, barbotage chemical effects (BCE), mechanisms of BCE, structural temperature of water, marine aerosols.

Cite this article as: Kushnir, S.V., Kost, M.V., Kozak, R.P. WPT STN (2016) 20:30. | Download (PDF)

04.04.2017 at 7:30 pm

THE PROTECTION OF NATURAL RESERVOIRS FROM POWER PLANT ACCIDENTAL POLLUTIONBY COPPER IONS

UDC 628.33: 628.5432(088.8)

G. G. Trohymenko1, M. D. Gomelya2

1Admiral Makarov National University of Shipbuilding, Mykolaiv, Ukraine
2National Technical University of Ukraine, Kiev Polytechnic Institute, Kiev, Ukraine

e-mail: gomelya@users.ntu-kpi.kiev.ua

The results of the water stabilization treatment studies to feed the cooling water circulation systems by ion exchange method are reported. The processes of the water softener on strongly and weakly acidic cation resins in the presence of copper ions are studied. The relation of the water purification efficiency from copper and its softening depending on the form of the ion-exchanger and water consumption was determined. It is shown that the use of weakly acidic cation resin in the acid form provides nearly complete decarbonization of water by partial acidification. The use of ion exchangers in salt form allowsto neutralize the waterwith effective mitigation and clean-up of the copper ions. The processes of cation resin regeneration by acidic and saline solutions were analyzed. It is shown that the make-up cooling systems by softened water will introduce stagnant circulation cooling system that will provide reliable protection of waters from pollution by power plan wastewater copper ions.

Keywords: cation resin, heavy metals, ion exchange,ion-exchanger regeneration, water circulating systems.

Cite this article as: Trohymenko, G.G., Gomelya, M.D. WPT STN (2016) 20:48. | Download (PDF)

04.04.2017 at 7:07 pm

WATER TREATMENT BIOTECHNOLOGY FOR BREEDING OF SHARPTOOTH CATFISH IN THE RAS

UDC 628-35

S. V. Konontcev

National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kiev, Ukraine

e-mail: akula13@ukr.net

The aim of this work is to study the features of contaminated water formation in the recirculation aquaculture systems (RAS) plants for breeding of sharptooth catfish (Clarias gariepinus, Burchell 1820) and to develop the effective biotechnology for water quality recovering to allow water reuse. Disadvantages of classical water treatment technology from dissolved nitrogen compounds by using the nitrification with following denitrification lead to significant slowdown in the fish growth and increase the cost of products. On the basis of the analysis of pollutants concentrations in the catfish farm, which is working on the RAS-principle, the features of contaminated water formation and the reasons of low efficiency of facilities for mechanical and biological treatment were determined. The biotechnology that provides effective removal of dissolved nitrogen and phosphorus compounds by using phytoreactor with floating aquatic plants was proposed. Expediency of using molluscs in the processes of transformation of undissolved organic compounds in RAS water was proved. A comprehensive scheme of biological water treatment in RAS-plants for breeding of catfish was developed.

Keywords: water treatment, nitrogen removal, RAS, biotechnology.

Cite this article as: Konontcev, S.V. WPT STN (2016) 20:57. | Download (PDF)

04.04.2017 at 6:38 pm