Kinetics of Reaction-Crystallization of Struvite in the Continuous Draft Tube Magma Type CrystallizersmInfluence of Different Internal Hydrodynamics

从 Mg 2+, NH 4+ 和 PO 43− 离子的冲淡的水答案的鸟粪石合成的一个实验室规模反应结晶化过程被学习。研究用暂停的内部循环盖住连续喷气泵草稿试管岩浆(DTM ) 类型 crystallizers 的二原来的构造的测试(向上 / 向下) 。在之间的相互作用构造上，水动力学和运动因素被建立并且讨论。成核和鸟粪石晶体的线性生长率根据人口密度分发被计算。理想化的混合暂停的运动模型就尺寸依赖者生长机制而言的混合产品移动(MSMPR ) crystallizer 被使用(Rojkowski 夸张方程) 。为比较目的，运动数据对应于与推进器煽动者装备的更简单的、连续草稿试管类型 crystallizer 被分析。更大的尺寸的水晶产品在一个混合房间从暂停的下降流动的喷气泵 DTM crystallizer 被撤退，这被结束。

A laboratory-scale reaction-crystallization process of struvite synthesis from diluted water solution of Mg^2＋, NH^＋ 4 and PO3- ions was studied. The research covered the tests of two original constructions of continuous jet-pump Draft Tube Magma （DTM）-type crystallizers with internal circulation of suspension （upward/downward）. Interactions between constructional, hydrodynamic and kinetic factors were established and discussed. Nucleation and linear growth rates of struvite crystals were calculated on the basis of population density distribution. Kinetic model of idealized Mixed Suspension Mixed Product Removal （MSMPR） crystallizer considering the size-dependent growth mechanism was applied （Rojkowski hyperbolic equation）. For comparison purposes the kinetic data corre- sponded to a simpler, continuous draft tube-type crystallizer equipped with propeller agitator were analyzed. It was concluded that crystal product of larger size was withdrawn from the jet-pump DTM crystallizer of the descending flow of suspension in a mixing chamber.