Traditional processes applied in water softening and lime scale prevention are ion exchange and reverse osmosis. Both methods remove excess hardness salts from water. These are reliable but rather expensive methods. An alternative way to prevent limescale formation is the structural change of hardness salts into modifications that remain in suspension in small particles and do not form hard crystalline deposits. Scale usually consists of calcium carbonate in the calcite modification. However, there is another modification of calcium carbonate – aragonite. Aggregation of aragonite crystals and their adsorption on solid surfaces are substantially lower than those of calcite. Aragonite precipitates in the form of fragile and loose particles and stays in the bulk of the liquid rather than deposit on the walls of pipes and appliances.
Until recently, magnetic descaling of water was the only method based on the aragonite formation. Our fantastic new generation filter called Drinking Filter produces a similar effect. Treatment of hard water with an EcoAgua filter in various geographical regions revealed that the water passed through the saturated filter does not form scale and even more impressive gradually washes away the old scale. This phenomenon referred to as “quasi-softening” of water, was studied in detail. Formation of aragonite structure of hardness salts as a result of water passage through our EcoAgua filter was confirmed experimentally. The structural transformation of the precipitate to form rhombic aragonite crystals is clearly seen through a microscope. As determined by X-ray diffraction, the content of aragonite modification of calcium carbonate in water substantially increases after filtration through EcoAgua filter. Conventional hard water study with Vienna University performed on hard water in Spain, Austria, and Germany, confirmed the “quasi-softening” of the water due to the accumulation of aragonite. On the basis of obtained results, a mechanism of this phenomenon was proposed.
Let us consider transformations of hardness salts during filtration, Hardness salts exist in aqueous solutions in the form of metastable clusters. The sorbent used in the EcoAgua filter has a porous structure of tortuous channels. Constantly increasing pressure produced during the passage of these clusters through narrow sections of such channels (see the figure) shifts the chemical equilibrium towards the formation of carbon dioxide, which is always present in water. Chemical reactivity of eco-polymer in combination with its highly developed porous structure provides recrystallization of calcite into aragonite. At the outlet of the eco-polymer, the pressure increases to the maximum value and then sharply decreases. Liberated carbon dioxide readily escapes from the water. A similar gas escaping effect is observed when we open a bottle of carbonated drink. After the liberation of carbon dioxide the pH of water slightly increases, thus shifting the equilibrium towards carbonate formation. The solution is supersaturated with respect to calcium carbonates and aragonite nuclei are formed. The aragonite solubility decreases with further heating. Supersaturated solutions of aragonite are known to be less stable than those of calcite. Aragonite precipitates very rapidly in the bulk of the solution rather than deposit on the surfaces, which is of practical importance.
In the course of filtration through the EcoAgua filter, calcite is transformed into aragonite with a noticeable change in the mineral composition of water. The “quasi-softening” occurs without any other additional equipment and is due only to the unique properties of the EcoAgua filter material. The fact that aragonite water does not form scale and gradually dissolves old deposits suggests similar behavior of such water in a living organism. It is probable that such water can dissolve nephroliths (kidney stones). The influence of water filtered through the eco-polymer filter on living organisms was studied at the Military Medical Academy. Double blind experiments were conducted with two groups of Wistar rats over a period of 30 days. Animals in the first group were fed with hard tap water. Animals in the other group drank the same water filtered through the filter. Prior to the experiments, the filter was operated for a long time in the hard water in order to ensure its saturation with calcium and magnesium salts. As a result, the hardness of initial and filtered water used in the experiments was similar. This made it possible to conduct the studies with water of the same composition, where the “quasi-softening” the effect was the only variable. The most pronounced differences were found in urine deposits (see fig.1). Urine of animals in the first group contains large crystals capable of forming nephroliths. These crystals are thought to inflict damage to internal tissues of kidneys and urinary tracts. This assumption is confirmed by the presence of proteins and blood in the urine. These micro injuries can contribute to the development of internal infections.
➤ Urine composition of rats fed with (A) tap & (B) filtered water.
Consumption of EcoAgua filtered hard water leads to the decrease of both the size and the number of crystals present in urine.This positive change in the urine composition was observed in the animals fed with calcium-rich water since aragonite is assimilated more easily than calcite. Thus, aragonite water obtained with the filter facilitates calcium assimilability, improves functions of the gastrointestinal tract and liver, decreases kidneys loading, and reduces the chances of nephrolith formation. Water filtered through the EcoAgua filter can be used as a non-medicational prophylactic means against urolithiasis.