Control Of Calcium Carbonate Scale Formed on a Pipe with Inducing Magnetic Field and Tartaric Acid in Flowing Water

The polymorphic forms of calcium carbonates precipitatedfrom water flow in a pipe at a rate of 30 ml/min in a crystal growth simulatorwere investigated in the study. Specifically, the calcium carbonates formed under the influence of the electromagnetic field and tartaric acid (0, 5, and 10 ppm) and varying temperatures (30, 40 and 50 OC) were analyzed by XRD, SEM and FTIR methods. As a result, the nucleation time of the first crystal form was longer, while the deposition rate decreased with the increasing tartaric acid additive. Obviously, the presence of tartaric acid at 400C inhibited the calcium carbonate formation and the deposition rate reduced dramatically from 0.402 to 0.211 mg/h. The resulting calcium carbonates were dominated by a high proportion of calcite with the minor vaterite. Conversely,the presence of the induced magnetic field and the tartaric acid provided the high proportion of vaterite. Morphology of the polymorphic forms of calcium carbonate showed rhombohedral calcite and vaterite like a flower structure as confirmed by the SEM method. FTIR analysis confirmed a mixture of calcite and vaterite coexisting in the precipitating solid.