Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

OP-II-3Taking into account these previous studies on crystallization processes in fluidized bedreactors, this work was involved in the fluoride recovery as solid product CaF 2 with theobjectives of (i) the improvement of process efficiency by means of the reduction of finesformation with multiple feed points of Calcium into the reactor, and (ii) the simulation of thefluidized bed reactor to describe the effect of the distribution of the supersaturation, with theintroduction of the product growth model and the fines formation equation in order to predictthe process efficiencies in terms of fluoride removal and recovery as solid product and.The experimental results of process efficiency at laboratory scale indicated a significantincrease of 20 % when three feed points of Calcium where used in comparison to one point atthe bottom of the reactor, working with fluoride concentration of 500 mg/l at the inlet of thereactor. The process simulation also provided the estimation of the benefits on theconsumption of raw materials and waste disposal, and it is used as an important tool to scaleup the process for its integration into the production lines.AcknowledgmentsThis research is financially supported by the Spanish Ministry of Science and Technology(Project CONSOLIDER CTM2006-00317).References1. Irabien, A., Garea, A., Aldaco, R., Perez, O., Saenz, J.M., Patent number ES2270705, 01/04/2007.2. Aldaco, R., de Luis, P., Irabien, A., Fluidized bed reactor for fluoride removal, Chem. Eng. J., 107, 113-117,2005.3. Aldaco, R., Garea, A., Irabien, A., Calcium fluoride recovery from fluoride wastewater in a fluidized bedreactor, Water Res., 41, 810–818, 2007.4. Garea, A., Aldaco, R., Lopez, E., Irabien, A., Pilot plant operation of a fluidized crystallization process forcalcium fluoride recovery, 5 th European Meeting on Chemical Industry and Environment, Vienna, 2006.5. Aldaco, R., Garea, A., Irabien, A., Modelling of particle growth: application to water treatment in a fluidizedbed reactor. Chem. Eng. J., 134, 66-71, 2007.6. Aldaco, R., Garea, A., Irabien, A., Particle growth kinetics of calcium fluoride in a fluidized bed reactor,Chem. Eng. Sci., 62, 2958-2966, 2007.7. Aldaco, R., Garea, A., Irabien, A., Fluoride recovery in a fluidized bed :crystallization of calcium fluorideon silica sand, Ind. Eng. Chem. Res., 45, 796 –802, 2006.8. Costodes, V.C., Lewin, A.E., Reactive crystallization of nickel hydroxy-carbonate in fluidized-bed reactor:fines production and column design. Chem. Eng. Sci., 61, 1377-1385, 2006.9. Seckler, M.M., Bruinsma, O.S.L., van Rosmalen, G.M., Phosphate removal in a fluidized bed- I.Identification of physical processes. Water Res., 30, 1585-1588, 1996.10. Battistoni, P., Deangelis, A., Pavan, P., Prisclandaro, M., Cecchi, F., Phosphorous removal from a realanaerobic supernatant by struvite crystallization, Water Res., 35, 2167-2178, 2001.80