Axial dispersion in the three-dimensional mixing of particles in a rotating drum reactor

Horizontal drum reactors are widely used in industry for the processing of granular material. They are ideally suited for chemical processes that require high temperatures at near-atmospheric pressure. However, the complexities of these reactors have resulted in empirical design procedures that lead to very conservative and costly reactors. This study first reviews critically the extensive literature on experimental results obtained on rotary kilns (without flights) and proposes new design equations for the axial-dispersion coefficient in terms of rotational speed, degree of fill, drum diameter, and particle diameter. A total of 179 data points from the literature, encompassing both the batch and the continuous operational modes, yielded design correlations for slumping, rolling/cascading and cataracting bed behaviours. Additionally, new measurements were made on a pilot-scale rotary drum by tracking a single radioactive particle (emitting gamma-rays) using a battery of nine scintillation counters; these data confirmed the correctness of the proposed design correlations.

[1]  J. K. Brimacombe,et al.  Experimental study of transverse bed motion in rotary kilns , 1983 .

[2]  Douglas W. Fuerstenau,et al.  Material transport in a continuous rotary drum. Effect of discharge plate geometry , 1977 .

[3]  Jpk Seville,et al.  Positron emission particle tracking studies of spherical particle motion in rotating drums , 1997 .

[4]  Dan Luss,et al.  Axial dispersion of solid particles in a continuous rotary kiln , 1995 .

[5]  J. K. Brimacombe,et al.  The modeling of transverse solids motion in rotary kilns , 1983 .

[6]  A. D. Damodaran,et al.  Residence time distribution and material flow studies in a rotary kiln , 1990 .

[7]  S. H. Tscheng,et al.  Convective heat transfer in a rotary kiln , 1979 .

[8]  Leonard G. Austin,et al.  Axial mixing of particles in batch ball mills , 1973 .

[9]  J. Chaouki,et al.  3‐D mapping of solids flow fields in multiphase reactors with RPT , 1995 .

[10]  Douglas W. Fuerstenau,et al.  The mixing of trace quantities into particulate solids , 1969 .

[11]  Denis Ablitzer,et al.  Experimental study of residence time, particle movement and bed depth profile in rotary kilns , 1995 .

[12]  Robin P. Gardner,et al.  A Monte Carlo method for simulating dispersion and transport through horizontal rotating cylinders , 1979 .

[13]  Karl Schügerl,et al.  Longitudinal mixing in horizontal rotary drum reactors , 1978 .

[14]  Baumann,et al.  Surface properties and the flow of granular material in a two-dimensional rotating-drum model. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[15]  Masami Nakagawa,et al.  Steady particulate flows in a horizontal rotating cylinder , 1998 .

[16]  Douglas W. Fuerstenau,et al.  Simulation of diffusional mixing of particulate solids by Monte Carlo techniques , 1967 .

[17]  G. A. Kohring Studies of diffusional mixing in rotating drums via computer simulations , 1995 .

[18]  Julio M. Ottino,et al.  Particle dynamics simulation: a hybrid technique applied to granular mixing , 1998 .

[19]  Fernando J. Muzzio,et al.  Mixing of granular material in a drum mixer undergoing rotational and rocking motions I. Uniform particles , 1998 .

[20]  Jennifer May Black Particle motion and heat transfer in rotary drums , 1988 .

[21]  Douglas W. Fuerstenau,et al.  Diffusional mixing in an ideal system , 1966 .

[22]  K. S. Hatzilyberis,et al.  AN RTD STUDY FOR THE FLOW OF LIGNITE PARTICLES THROUGH A PILOT ROTARY DRYER. PART II : FLIGHTED DRUM CASE , 1999 .

[23]  A.A.H. Drinkenburg,et al.  SOLIDS MIXING AND RESIDENCE TIME DISTRIBUTION IN A HORIZONTAL ROTARY DRUM REACTOR , 1976 .

[24]  Jochen Mellmann,et al.  The transverse motion of solids in rotating cylinders—forms of motion and transition behavior , 2001 .

[25]  Jamal Chaouki,et al.  Experimental characterization of the solid phase chaotic dynamics in three-phase fluidization , 1995 .

[26]  Jacob Mu,et al.  The mixing of Granular solids in a rotary cylinder , 1980 .

[27]  J. Chaouki,et al.  A γ-ray detection system for 3-D particle tracking in multiphase reactors , 1994 .

[28]  R. Rutgers,et al.  Longitudinal mixing of granular material flowing through a rotating cylinder: Part II. Experimental , 1965 .

[29]  M. B. Donald,et al.  The mixing of solids in tumbling mixers—I , 1962 .

[30]  Suresh K. Bhatia,et al.  Axial transport of granular solids in rotating cylinders. Part 2: Experiments in a non-flow system , 1991 .

[31]  Volkhard Buchholtz,et al.  Simulation of rotating drum experiments using non-circular particles , 1995, cond-mat/0203589.

[32]  Douglas W. Fuerstenau,et al.  The influence of operating variables on the residence time distribution for material transport in a continuous rotary drum , 1974 .