The effect of ultrasonic field on calcium carbonate scale formation

A retardation effect (62-76%) was observed on the crystallization of calciu m carbonate in the presence of an ultrasonic applied field (0.56 w/cm(2)). The apparent order of crystal growth of calcite was found to be n= 2 +/- 0. 2 for the seeded growth experiments and n= 6.7 +/- 0.2, n= 5.3 +/- 0.1 for the spontaneously precipitated vaterite in the absence and presence of the ultrasonic field, respectively. The mechanism, the nature, the morphology a nd the size of the crystals formed was not influenced by the applied ultras onic field, which may possibly affect the dehydration step of the growth un its or the migration step of the dehydrated growth units to the active grow th sites. (C) 2001 Elsevier Science B.V. All rights reserved.