Abstract The understanding of hydrodynamic characteristics and particle size distribution (PSD) of solid–liquid disengagement is crucial to design a continuous thickener for the reconversion step of nuclear fuel reprocessing. Disengagement of dispersed cerium oxalate from nitric-oxalic acid medium in a batch settler is experimentally investigated to find out solid volume fraction and PSD with different overall solid fraction followed by simulations to determine the position of active interface (AI). Eulerian-Eulerian simulations of the disengagement process were performed and the predicted solid phase volume fraction at different heights of the settler was verified using the experimental data. The predicted AI followed a good trend for different overall solid fraction. Owing to the constant particle size considered in the simulation, a difference between the predicted and measured solid phase volume fraction was observed. The predicted AI, measured solid volume fraction and PSD could aid the design of continuous thickener for nuclear fuel reconversion.

中文翻译：

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在间歇沉降器中从硝酸-草酸介质中分离分散的草酸铈：测量和 CFD 模拟

摘要 了解固液分离的流体动力学特性和粒度分布 (PSD) 对于设计用于核燃料后处理再转化步骤的连续增稠器至关重要。实验研究了分散的草酸铈从分批沉降器中的硝酸-草酸介质中的脱离，以找出具有不同总固体分数的固体体积分数和 PSD，然后进行模拟以确定活性界面 (AI) 的位置。对脱离过程进行了欧拉-欧拉模拟，并使用实验数据验证了沉降器不同高度的预测固相体积分数。对于不同的整体固体分数，预测的 AI 遵循良好的趋势。由于在模拟中考虑了恒定的粒径，观察到预测的和测量的固相体积分数之间存在差异。预测的 AI、测量的固体体积分数和 PSD 可以帮助设计用于核燃料再转化的连续浓缩器。