Abstract: Axial mixing of continuous phase in a rotating disk extraction column has been studies by considering the flow characteristics of fluids in the column. Equations were developed to predict the effects of rotation speed of the disks, continuous-phase flow rate and disperse-phase flow rate on the axial mixing of the continuous-phase. For single phase flow, the overall axial mixing can be considered as the combined contribution from eddy diffusion and channeling phenomenon. The axial mixing of continuous-phase in single phase flow can be described by the following equation: For two phase counterflow in the column, the axial mixing of continuous-phase becomes even more complex owing to swarming of drops of disperse-phase. Physical model developed as well as experimental results indicates that axial mixing of continuous-phase could either be enhanced or diminished by the disperse-phase flow as operating conditions vary. The motion of wakes of continuous-phase behind the drops increases thebackmixing of continuous-phase. The backmixing ratio fw, from the wake movement can be represented by The movement of a swarm of drops in a continuous-phase reduces the channeling flow of continuous-phase and thus forward mixing. Decrease of the ratio of forward mixing AW can be correlated by The total contribution of disperse-phase to the axial mixing of continuous-phase is given by (fw-△W). Experimental results of axial mixing of continuous-phase in two phase counter-current flow can be represented satisfactorily by the following equation:

摘要： 根据塔内流体运动规律,分别研究了转盘萃取塔单相流和两相逆流时连续相轴向混合的机理.采用光导纤维测定脉冲示踪的浓度响应,从而得到单相流轴向混合Peclet数和两相逆流时分散相对连续相轴向混合的影响(f_w-△~W)的数学表达式.这些表达式对轴向混合的计算,能从高转盘转速扩展到低转速,并能适用于较广的流速范围.为了分析连续相的轴向混合,对分散相滞留量及分散相液滴直径也作了初步研究,并得出了关联式.