Effect of electromagnetism on the formation of calcium carbonate crystals: presence of calcite and aragonite

Abstract

The formation of scale in systems that work with hot water is a problem that can generate economic losses in domestic and industrial installations. A great variety of techniques soften the water, but modify the chemical composition and generate waste streams. An alternative is the use of the electromagnetic techniques, which prevent scale formation without altering the quality of the water, however, the mechanism is not entirely clear. One of the theories proposed is that the precipitation of calcium carbonate such as aragonite (less encrusting) is favoured compared to calcite (encrusting). In this study, the rapid controlled precipitation test has been used to precipitate calcium carbonate from synthetic waters, which are previously prepared by dissolving calcium carbonate in distilled water, treated with the TK3K equipment (Ecotécnica Energy Systems, S.L.), and bubbling with CO2 until complete dissolution. These studies were compared with others without electromagnetic treatment of the distilled water. The controlled rapid precipitation tests were carried at 600 rpm and the obtained crystals were analysed with a polarized light optical microscope (OPTIKA NP-400T). Untreated samples were found to be calcite (rhombohedral), with no other mineral phases and the treated samples had presence of aragonite (orthorhombic), together with calcite.