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2023-12
Lime Hydration Mechanism Quicklime mixed with water produces calcium hydroxide. The mixing reaction produces Ca2+ and OH–, from which solid phase calcium hydroxide crystallizes. The lime hydration reaction mechanism is as follows: CaO +H2O →Ca(OH)2 Ca(OH)2 → Ca2+ +2OH–(solid surface) Ca2+ +2OH– → Ca(OH)2 (crystal) At the beginning of the reaction, under low agitating intensity, the entire hydration process is mainly controlled by the main liquid phase diffusion process of Ca+ or OH– on the CaO solid surface. As the agitation intensity increases, the influence of the chemical reaction begins to increase, driven by both diffusion and reaction. Because as the agitation rate increases, the diffusion liquid film on the solid surface becomes thinner, speeding up the diffusion rate of the reaction product, causing the apparent hydration rate of lime to increase accordingly, and the hydration process begins to be dominated by both diffusion and reaction. It is well known that the main factors affecting the hydration rate are agitation, quicklime particle size and hydration water temperature. 1.)The impact of agitation on the lime hydration process: Agitation intensity is a critical value. It must not only fully mix quicklime and water to prevent lime from agglomerating, but also reduce the heat loss of...