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Learn about creating artificial geochemical barriers with natural sorption materials, like zeolites and serpentines, to protect water bodies from radioactive nuclides. Discover innovative technologies for purifying water contaminated with heavy metals, arsenic, and toxins, providing clean water solutions for emergencies. Explore the development of new sorption materials and technologies and the global issue of arsenic pollution in drinking water.
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Aftermath of Fukushimaproviding solutions for the localities by clean water for the period of large-scale emergencies
Joint Stock Company, Scientific and Technical Enterprise “Radiy” , Moscow, Russia V. I. Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow Ralph T. Niemeyer, Director Int’l. Dept. Chasovaya ul.,28, 125057, Moscow, Russia Tel. +7(495)151-15-21, Fax. +7(495)152-69-14 E-mail: niemeyer@radiy-niod.ru
1. The development of artificial geochemical barriers to protect water bodies from contamination by radio-nuclides
One of the waysfor solving the problem of migration of nuclides and toxic elements may be the creation of artificial geochemical barriers (permeable barriers)around the contaminated sites (barriers - deep ditches filled with granulatefiltering material, permable to water and non-toxic components) The main conditionfor ensuring the possibility of creating the barriers is the presence of widely available and cheap filtering and sorption materialswith two basic properties: - high selectivity to removable toxic components; - no contaminating effects in the material itself.These requirements are largely met by some of the natural sorption materials, in particular, zeolite-containing rocks and modified zeolites.
Nano - Composites. Chemically Modified Natural Zeolites Cr 8 Cu 7 U 6 5 4 lg K 3 2 1 0 0 2 4 6 8 10 pH • Before modification • Cation-exchanging properties. Selectivity to Sr and Cs • After the modification • cation- and anion-exchanging properties. Additional Selectivity to U and other heavy radio-nuclides • Options: magnetic properties (for using powders), bactericidal properties. Concentration coefficients for Cr, Cu and UO2(CO3)4-dependently on рН
Protection of the Prypyat River Fourth Block of Chernobyl NPP in1986. Industrial Working Place More than 10 barriers each with 2 000 – 4 000 tons of zeolite have been constructed
Elaboration and computation of the artificial geochemistry barrier Craton-3 in Yakutia(the place has been contaminated after the underground nuclear explosion in 1970ies)
Protection Times of the Barrier at Different Conditions L=200 cmc/c0=0.1
2.New sorption materials and technologies for water treatment Natural sorption materials and chemically modified natural materials and nano-materials: aluminosilicates (zeolites), magnesium and iron silicates (serpentines)
Automated Stand for Testing Sorption Materials in Column Regimes
Natural sorption nano-materials Serpentine minerals (Mg,Fe)6[Si4O10](OH)6with the impurities of Fe3O4, Cr2O3, NiO, MnO, CoO, СаО, Al2O3 Elementary fibers of the serpentine are hollow: Internal diameter 13 nm and external 25nm.(J. Girard, Principles of Environmental Chemistry, Jones & Bartlett Publ., 2005.)
12 Scanning the serpentine surface (specially prepared ) with Atomic Force Microscope Scan area: horizontal - 160 x 160 nm; vertical - 10 nm; black - "depression“; white - "top“.
Chemically activated serpentinites New Sorption Materials «SKOV» Patent of Russian Federation: 2316479. European Patent Application (WiPO) : WO/2007/111531 The Enterprise “Radiy” has a license for exploitation of the deposit of 50 million tons One of the best known in the world of materials for removal of iron. Simultaneous purification from iron, manganese, heavy metals, arsenic, fluorine and boron, removing turbidity and color. Independent tests conducted in different countries. Bactericidal Properties
Removal of iron from brackish well water in cyclic processes: sorption-back washing. Initial Fe -content: 6.1 mg/l, TDS=4.9 g/l (Total mineralization). Sorption material - granulated SKOV, 1-1.5 mm of grain sizes Column bed: L = 350 mm, S= 2950 mm2 , BV = 1 liter. Independent tests performed by the "ECOSOFT" JSC, Kiev, Ukraine The sensitivity of the purification process to flow rate was checked. During the continuous passing initial water trough the sorption bed, the flow rate was kept 10 l/h, then, elevated two times, up to 20 l/h, and then, reduced back.
Decontamination of drinking water from arsenics Mounting spring water fro the North Caucasus region Initial As -content: 0.064 mg/l (64 g/l), TDS=0.43 g/l .
ARSENICS PROBLEM IN THE WORLD Natural arsenic pollution is a global phenomenon for 70 countries on all continents, except Antarctica,. In recent decades about 140 million people worldwide have been exposed to drinking water containing more than 10 μg/L of arsenic.” WHO's activities on arsenic In 1963 the standard was estimated to be 0.05 mg/L. In 1984, this was maintained as WHO's "Guideline Value"; and many countries have kept this as the national standard or as an interim target. According to the last edition of the WHO Guidelines for Drinking-Water Quality (1993): Inorganic arsenic is a documented human carcinogen. 0.01 mg/L was established as a provisional guideline value for arsenic. Based on health criteria, the guideline value for arsenic in drinking-water would be less than 0.01mg/L.
Water preparing for cottages (1-2 cub.m/|day) Typical nit with capacity 240 cub. m/day for Childcare Water Purifying Units of Different Scales
INDUSTRIAL SCALE UNIT FOR WATER PURIFICATION 2000 м3/day (from underground water enriched with iron, fluoride and boron)