Effect of Particle Size Distribution on Ammonium Sulphate Dried in a Rotary Dryer

Susianto Susianto, Ali Altway, Kuswandi Kuswandi, Margono Margono


The aim of this work is to study theoretically, by mathematical model development, the effect of particle size distribution on the performance of rotary dryer to dry ammonium sulphate fertilizer assuming plug flow with axial dispersion pattern (PFDA model) for solid particle flow. The mathematical model development was carried out by combining the drying processes model with particle size distribution model. Particle size distribution models used are Rosin-Rommler model and Gamma distribution model. For simplicity, the model of drying processes of solid particles in the rotary dryer was developed by assuming of uniform air conditions (temperature and humidity) along the rotary dryer as in the entry conditions. The resulting differential equations were solved analytically under Matlab 6.1 facility.Since this model, solid hold up, and axial dispersion number were obtained from empirical correlations in the literatures. The drying rate of ammonium sulphate fertilizer in rotary dryer was estimated using isothermal diffusion model with effective diffusivity of moisture in the particle obtained from previous study [2]. Using Gamma function distribution, this research showed that for the value of the coefficient of variance (CV) less than 0.5, particle size distribution does not have significant effect on dryer performance. For the value of CV greater than 0.5, the dryer performance increase (or outlet solid moisture content decrease) with increasing the value of CV. The application of Rosin-Rammler model gives lower prediction of outlet solid moisture content compared to the application of Gamma function model.


Particle size distribution; coefficient of variation; moisture content; analytical solution

Full Text:



E. K. Akpinar, I. Dincer, 2005, “Application of moisture transfer models to solid drying”, Proceeding of the Institution of Mechanical Engineers, 219, A3.

R. Caesaryanto, S. AlRasyid, Margono, K. Budikarjono, Susianto, A. Altway, 2009, ”Eksperimen dan simulasi karakteristik pengeringan pupuk ammonium sulfat”, Proceeding Seminar Aptecs.

L. T. Fan, Ahn, and Yong-Kee, 1961, “Axial dispersion of solids flow systems”, Applied Scientific Research, vol.10, no.1, pp. 465-470.

N. J. Fernandes, C. H. Ataide, and M. A. S. Barrozo, 2009, ”Modeling and experimental study of hydrodynamic and drying characteristics of an industrial rotary dryer”, Brazilian Journal of Chemical Engineering, Volume 26, No 2, pp. 331-341

S. J. Friedman, W. R. Jr. Marshall, 1949a, “Studies in rotary drying - Part 1. Hold up and dusting”, Chem Eng Progress, vol.45, no. 8, pp. 482-493.

S. J. Friedman, W. R. Jr. Marshall, 1949b,” Studies in rotary drying - Part 2. Heat and mass Transfer”, Chem Eng Progress , vol.45, no. 9, pp. 573-588.

C. J. Geankoplis, 2003, Transport Processes and Separation Process Principles (Including Unit Operations, 4th ed., Pearson Prentice Hall.

A. K. Haghi, F. Z. Angiz, 2007, “Heat and mass transfer in thermal drying of wool: a Theoretical Approach”. The Proceeding of The 5th Asia-Pacific Drying Conference, vol.1.

A. K. Haghi, 2001 , “Simultaneous moisture and heat transfer in porous system”, Journal of Computational and Applied Mechanics, 2(2), 195-243.

A. K. Haghi, 2003, “Diffusion of heat and moisture through textiles”, Int. Journal of Applied Mechanics and Engineering, 8(2), 233-243

J. J. Kelly, 1995, “Rotary drying” In: Mujumdar A S (ed), Handbook of Industrial Drying, Marcel Dekker, Inc., New York, vol.1, pp. 161-183.

I. C. Kemp, 2004, “Comparison of particle motion correlation for cascading rotary dryers”, Proceeding of the 14th International drying symposium, Brazil, Vol.B, pp. 790-797.

C. T. Kiranoudis, Z. B. Maroulis and Marinos-Kouris

,”Modeling and optimization of fluidized bed and rotary dryers”, Drying Technology, pp. 735-763.

Liang-Tseng F, Ahn, and Yong-Kee, 1961, “Axial dispersion of solids flow systems”, Applied Scientific Research, Vol. 10, no.1, pp. 465-470.

M. H. Lisboa, A. B. Alves, D. S. Vitorino, W. B. Delaiba, J. R. D. Finzer, and M. A. S. Barrozo, 2002, “A study about particle motion in rotary dryers”, 2nd Mercosur Congress on Chemical Engineering.

A. S. Mujumdar, and W. Zhonghua, 2007, “Thermal drying technologies: New developments and future R & D potential”, The Proceeding of The 5th Asia- Pacific Drying Conference, Vol. 1.

N. V. Menshutina, H. Leuenberger, A. Y. Troyankin and M. N. Puchkov, 2007, “Mathematical modeling as approach to design of drying process”, The Proceeding of The 5th Asia-Pacific Drying Conference, Vol. 2.

J. P. Pan, T. J. Wang, J. J. Yao and Y. Jin, 2006, “Granule transport and mean residence time in horizontal drum with inclined flights”, Powder Technology, 16, pp. 50 – 58.

R. F. Pacheco, and S. S. Stella, 1998, “Calculating capacity trend in rotary dryer”, Brazilian Journal of Chemical Engineering, Vol 15, No 3.

R. H. Perry, and C. H. Chilton, 1973, Perry’s Chemical Engineers Handbook, 5th ed., McGraw-Hill

H. Purutyan, J. W. Carson, and T. G. Troxel, 2004, “Improve solids handling during thermal drying” Chemical Engineering Progress, 100, 11.

F. R. Schofield, and P. G. Glikin, 1962, “Rotary dryers and coolers for granular fertilizers”, Trans. I Chem.E. Vol. 40, pp. 183-190.

C. Strumillo, and T. Kudra, 1986, Drying: Principles,

Applications and Design, Gordon and Breach Science

Publishers, Montreaux, pp. 71.

N. C. Tsourveloudis, and L. Kiralakis, 2003, “Rotary drying of olive stones Fuzzy modeling and controle”, University Campus, Chania GREECE, {nikost,kyralakis}@dpem.tuc.gr

F. Y. Wang, I.T. Cameron, J.D. Litster, and P.L. Douglas, 1993, “A Distributed parameter approach to the dynamics of rotary drying processes”, Drying Technolog, Vol. 11, no. 7, pp. 1641-1656.

L. Yliniemi, 1999, “Advanced control of a rotary dryer’, PhD Thesis, Department of Process Engineering, University of Oulu, Finland.

DOI: http://dx.doi.org/10.12962/j20882033.v21i3.37


  • There are currently no refbacks.

Creative Commons License

IPTEK Journal of Science and Technology by Lembaga Penelitian dan Pengabdian kepada Masyarakat, ITS is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Based on a work at https://iptek.its.ac.id/index.php/jts.