Local Installations
LOCAL INSTALLATIONS
FOR POTABLE WATER SUPPLEMENT
B. M. Kats
Physical Research Institute, University of Odessa,
27 Pastera St., Odessa, 65026, Ukraine
The potable water is one of the most valuable products containing mineral and organic substances of different types necessary for a man. However alongside with useful substances it usually contains various poisonous products (chlorine, heavy metal salts, nitrates, pesticides, surfactants and oil products) which makes its consumption quite dangerous for a man.
One of the modern ways of the population supply with the extra-purified potable water is the creation of the water purification installations intended for harmful admixture removal. Since 60s such installations have been used abroad, and they appeared in the USSR in the end of 70s.
Nowadays, industrial accidents more and more often lead to the contamination of the surface and underground water sources. It happens due to sudden throwing of great amounts of different types mineral combinations, including high toxic ones. The technical large water source purification often proves to be impossible. Thus the only way to supply the population with the guaranteed quality potable water is to use the special means, among which the WPIs can be considered the most substantiated ones for the additional potable water purification from harmful admixtures.
This report introduces the experimental results of “Midia-05M” practical work. “Midia-05M” is a third generation local polymodular water purification installation (WPI). It is meant for the mineral composition correction and additional potable water purification from toxic admixtures.
This water purification installation was worked out at the Physical Research Institute, University of Odessa. It was developed on the base of “Midia –05” the well known second generation water purification installation, which has already been used in Odessa for ten years, being a safe means of the Dniester water-line purification from the harmful admixtures. The WPI
“Midia-05M” consists of the mechanical filter, filter-adsorber, bactericide block, ion-exchange filter and device for its regeneration.
The WPI “Midia-05M” is supplied with the set of different ion-exchange filters, some of which are described below.
For the mineral composition correction of the potable water, containing the redundant quantity of hard cations (calcium and magnesium), ion-exchange filter is supplied with sulpfonated styrene divinilbenzene cationite KY-2-8 in sodium form, allowed for usage in the industrial-potable water supply. Washing it with NaCl solution, which can be found in the regenerating device, does the periodic cationite regeneration. The experiments have shown that using of 5-8% NaCl solution perfectly meets the requirements as to water and time consumption. The solution should be taken in the triple redundancy from its stoichiometric quantity, which provides most complete resin capacity restoration (85-90).
It is not always expedient to use sulfur cationite KY-2-8 for the potable water purification from the heavy metals (copper, lead, cadmium) because this cationite possesses rather a high selectivity for the ions of Ni2+, Cd2+, Pb2+, Cu2+, Zn2+ and Fe3+ as well as high adsorptivity of Mg2+ cations and especially Ca2+ cations. That is why ion exchange filter is supplied with polyampholyte ionite of aminocarboxilic type, for which the typical row of selectivity is as follows: Mg2+
Washing polyampholyte with NaHCO3 solution, which can be found in the regenerating device , does the periodic regeneration. The experiments have shown that using 3-5% NaHCO3 solution perfectly meets the requirements as to water and time consumption. The solution should be taken in five-ten redundancy to its stoichiometric quantity, which provides partial resin capacity restoration (30-35 %).
For purification of the potable water from cyanides ion-exchange filter is supplied with strong base anionite AB-17 in OH form, allowed to be used in the industrial-potable water supply. The row of selectivity for this anionite is as follows: OH-
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