Reactive crystallization of calcium carbonate by gas‐liquid and liquid‐liquid reactions

Abstract

Crystallization of calcium carbonate by gas-liquid and liquid-liquid reactions in a continuous MSMPR crystallizer was conducted over a wide range of suspension densities. The effects of operating factors and reaction mechanism o n the cyrstallization kinetics were investigated.The crystallization kinetics for both reaction systems are correlated by the power law model and these correlations depend on the suspension density regions. The kinetic orders in the power law model are correlated with carbonate alkalinity irrespective of the reaction mechanism and the suspension density.On a effectue la cristallisation de carbonate de calcium par des reactions gaz-liquide et liquide-liquide dans un cristalliseur MSMPR continu pour une large gamme de densites de suspensions. Les effets des facteurs de fonctionnement et du mecanisme de reaction sur les cinktiques de cristallisation ont ete ttudies.Les cinktiques de cristallisation pour les deux systtnies de reaction sont corrilies par le modele de loi de puissance et ces corrdations dependent des regions de densite de suspensions. Les ordres de cinktique dans le modele de loi de puissance sont corrtlts avec I'alcaliniti. du carbonate sans tenir compte du mecanisme de reaction et de la densite de suspensions.

A Novel Indirect Wollastonite Carbonation Route for CO2 Sequestration

“…7b), c) and d)). The observed aggregation phenomena, similar to the results obtained by other research groups [13], are due to the high supersaturation in the aqueous solution. The conversion of the carbonation reaction is relatively fast in the initial time (e.g.…”

Simulation of CaCO3 Crystal Growth in Multiphase Reaction

“…The usefulness of this model for the calcium carbonate precipitation (both an explicit integration and finite element method gave almost the same results) has been checked successfully by (Kangwook et al, 2002) but is necessary to remember, that the assumption of negligible agglomeration and breakage (limits of the model) can be applied only for the reactor where the particle density is maintained on the low level (Kataki & Tsuge, 1990). For the calcium carbonate precipitation in the batch reactor, breakage can be treated as a negligible phenomenon but the agglomeration is usually significant according to the high particle density in the reactor (Collier & Hounslow, 1999).…”

CO2 Absorption and Magnesium Carbonate Precipitation in MgCl2–NH3–NH4Cl Solutions: Implications for Carbon Capture and Storage

“…Soluble barium salt was used to absorb CO 2 via reactive crystallization [28][29][30], but was limited by the low natural abundance and toxicity. Ca(OH) 2 was also a possible absorbent [31,32], but Ca(OH) 2 solid is usually produced from CaCO 3 with CO 2 as a byproduct, negating its sequestering function. Reactive absorption of CO 2 in alkaline MgCl 2 solutions [33] or Mg(OH) 2 slurries successfully precipitated nesquehonite (MgCO 3 ·3H 2 O), a common mineral, at Earth's surface conditions [34,35].…”