| Titre : | Kinetics of CO2 stripping and its effect on the saturation state of CaCO3 upon aeration of a CaCO3 – CO 2 – H2O system : application to scaling in the papermaking process (2012) |
| Auteurs : | Patrick Huber, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Industrial & engineering chemistry research (Vol. 50 N° 24, Décembre 2011) |
| Article en page(s) : | pp. 13655–13661 |
| Note générale : | Chimie industrielle |
| Langues : | Anglais |
| Tags : | Kinetics Papermaking process |
| Résumé : | Calcium carbonate scaling is a critical problem in papermills. It often has been observed that scaling occurs in aerated sections of the process, where CO2 stripping from the solution is responsible for the saturation increase with respect to CaCO3. To better cope with scaling problems, it is important to be able to predict both supersaturation levels after aeration and the rate at which the system becomes supersaturated. In this study, trials are performed on a bubble column. Air is bubbled to strip out the dissolved CO2 from a CaCO3–CO2–H2O system. The saturation kinetics with respect to CaCO3 are followed by recording pH, and analyzed by speciation calculations. Aeration conditions are determined through gas hold-up and bubble size measurements. A general kinetic model is proposed to estimate how fast a solution will become saturated with respect to calcium carbonate during aeration. The model is applied to water quality and aeration conditions typically encountered in some unit operations of the papermaking process. Knowing the rate of change of calcium carbonate saturation will help papermakers to better estimate scaling risk in their process, and will help equipment suppliers to either minimize scaling problems in aerated sections of the process or design aeration units for calcium carbonate removal by controlled precipitation. |
| DEWEY : | 660 |
| ISSN : | 0888-5885 |
| En ligne : | http://pubs.acs.org/doi/abs/10.1021/ie200956z |
