Electromagnetic field influence on the calcium carbonate crystallization in the iron ions Fe²⁺ presence in mineralized aqueous media

The influence of electromagnetic field (EMF), created in the frequency range from 100 to 200 kHz, on the calcium carbonate crystallization from supersaturated aqueous solutions on the model system CaCl₂ - NaHC O₃ - FeSO₄ at 80°C at a molar ratio of CaCl₂:FeSO₄ (100:1), on the steel surface and in bulk was studied. It was found out that iron ions reduce the poorly soluble scales formed total mass (mainly CaCO₃) by ∼12%, both adhered to the steel surface and in the solution volume. Under the EMF influence, the adhered crystals amount on the steel surface in the Fe²⁺ ions presence decreases by 40% and in the absence by 14%. In volume, under the EMF influence, on the contrary, the crystals' number increased by 15% in the iron ions' presence, in the iron ions absence it decreased by ∼ 6%. In the Fe²⁺ ions presence and under the EMF influence, a decrease in the aragonite formation was noted while the calcite and vaterite content increased.