【摘要】 在总结流场条件影响吸附传质过程的同时,提出了流场分布影响液膜扩散传质的物理模型,指出不同的流场分布,液膜厚度变化不同,传质阻力也就不同,从而导致传质效果的不同.通过对传质方程中流速的物理意义进行重新定义,同时引入流场效应系数(Z),对传统的液膜扩散控制传质模型进行了修正,使模型中参数的物理意义更明确,并用13X沸石对Ca2+的吸附实验验证了该模型的合理性.结果表明,13X沸石对Ca2+的吸附传质效率与搅拌转速和叶片大小成正比,即与流场分布密切相关,其中流场分布比较规则的二次流场吸附传质效率最高;此外初始ρ(Ca2+)越高,传质越快,吸附效果越好,但流场分布影响越小,归结原因是此时传质动力的影响占据主导作用,超过了液膜阻力的影响,进而掩盖了流场分布对传质的影响.更多还原

【Abstract】 The physical model of liquid film diffusion was proposed on the basis of the influence of fluid field condition on liquid film diffusion.Different fluid fields and different liquid film thicknesses may lead to different mass transfer resistance,thus influencing the mass transfer effectiveness.Besides,liquid film diffusing control equation was modified by introducing fluid field effect coefficient Z and the new definition of fluid speed.In addition,the rationality of the modified model was proved by the adsorption experiment of calcium ion on 13X zeolite.The result showed that,the adsorption efficiency has relation with fluid field distribution.With the increasing of the concentration of Ca²⁺, the mass transfer speed become rapid,and the influence of fluid field distribution become little.This may attribute to the influence of mass transfer drive force which becomes much more important than liquid film resistance.更多还原