Study of Factors Related to Magnetic Treatment of Calcium Carbonate Saturated Water

摘要

Magnetic water treatment to reduce scale formation in industrial equipment has performed inconsistently in field trials. Laboratory studies have also shown mixed results. Recent research shows promising results for effects of magnetic treatment on calcium carbonate crystals and suspensions. Predictive application guidelines are a necessary condition to this technology practical. We used a test system with or without magnetic fields applied to produce supernatants and calcium carbonate crystal samples under controlled conditions of water temperature flow rate, rest duration, calcium carbonate concentration and number of magnetic device attached. XRD of crystals gave relative proportions of calcite and aragonite present and XRF measured transition metals and elements known to substitute for calcium in scale. Zeta potential and site distributions of charged particles were measured for samples of the supernatants. The fraction of calcite in crystals varied slightly relative to the estimated error of the method and correlated poorly with each test parameter, although qualitative effects of magnetic treatment were evident for certain test parameters. With increasing magnetic field, iron content in solid filter residues decreased, surface potential decreased, and particle size distribution showed increased counts at 6-35 micrometers.