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HomeAdvanced Materials ResearchAdvanced Materials Research Vol. 917A Comparison of Co-Current and Counter-Current...

A Comparison of Co-Current and Counter-Current Modes of Operation in Urea Prilling Tower

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Abstract:

In this paper, a model for urea prilling tower with co-current flow of cooling air and urea prills (particles) is presented. The process is modelled by simultaneous solution of the differential equations for hydrodynamics, heat and mass transfer between the air and prills. The process variables such as temperature, absolute and relative humidity of air along the height of the tower were obtained from this model. Temperature and moisture distribution of urea prills and their radial and vertical velocities were also calculated. The results of the present model were compared with the counter-current operation model available in the literature. The simulation results show that heat transfer performance for co-current operation is significantly less than that of the counter-current scenario. This is more pronounced for small prills, i.e. 1.0 mm than that of the large prills. The advantage of the model is that it can be used to investigate influence of operating parameters on efficiency of the co-current process. This also helps us to set the process control strategies for design and quality control purposes of the process.

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The Proceedings of the International Conference on Process Engineering and Advanced Materials 2012 (ICPEAM 2012)

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Periodical:

Advanced Materials Research (Volume 917)

Pages:

199-208

DOI:

https://doi.org/10.4028/www.scientific.net/AMR.917.199

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Online since:

June 2014

Authors:

Nejat Rahmanian*, Marjan Homayoonfard

Keywords:

Co-Current, Counter-Current, Prilling, Spray Cooling, Urea

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© 2014 Trans Tech Publications Ltd. All Rights Reserved

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