Preliminary experimental investigation into scale-up of agglomerative precipitation of calcium carbonate crystals

A scale-up experiments of CaCO₃ precipitation in 0.3, 1.0 and 5.0 dm₃ crystallizers were performed. For small input concentrations an influence of scale on product size and output concentration was observed. However, for large input concentration there was practically no effect detected. Bimodality of Particle Size Distribution (PSD) was once more time confirmed. Influence of the stirrer power input on PSD is most visible in the smallest vessel. A size-dependent aggregation-disruption model was used for extracting kinetic information. An experimental evidence was obtained that by the same stirrer power input (micromixing level) macromixing plays a very important role, deciding for output PSD and concentration.