Studies in Engineering and Technology Vol. 2, No. 1; August 2015 ISSN 2330-2038 E-ISSN 2330-2046 Published by Redfame Publishing URL: http://set.redfame.com 33 Conical Fluidized Bed with Arc Design for Improved Performance of Gas Distributor Ihsan Hamawand 1 , W. P. da Silva 2 , Ali H. Jawad 3 1 National Centre for Engineering in Agriculture, University of Southern Queensland, QLD 4350, Australia 2 Federal University of Campina Grande, Paraíba, Brazil 3 Material Engineering, University of Technology, IRAQ Corresponding: Ihsan Hamawand, NCEA, University of Southern Queensland, Building P9, West Street, 4350 Toowoomba, QLD, phone: +61-7-4631 2531, Australia Received: April 3, 2015 Accepted: April 18, 2015 Online Published: May 21, 2015 doi:10.11114/set.v2i1.836 URL: http://dx.doi.org/10.11114/set.v2i1.836 Abstract Particles distributions along a conical fluidized bed were predicted by an alternative arrangement of the minimum fluidization velocity equation. The proposed approach introduces two new equations which present the particle diameter in the bed as function of: height in the bed (Z), angle of inclination of the fluidized bed wall (θ), input flow rate (Q o ), and gas distributor diameter (D o , 2r o ). A novel arc-shaped design of the gas distributor was suggested, which provides enhanced distribution of the gas and enables greater control on the direction of the gas inlet. The model showed that the inclination of the fluidized bed wall should not exceed a critical angle, which can be determined with the set of equations specially developed for this purpose, to prevent inhomogeneous fluidization across the bed and accumulation of particles along the walls. By applying the Box Wilson Method, theoretical data were obtained for constant column diameter at the base (0.05 m), and varying bed height, Z, (range: 0.5 to 1.5 m), velocity of gas inlet, U, (range 0.25 to 1 m s -1 ), and balance factor, a, (range: 0.5 to 1, a new factor), respectively. The angle of inclination of the wall was first predicted based on the above parameters, and subsequently, the particle size distribution along the column was determined. Theoretically the novel arc-shaped distributor design has shown the potential of generating homogeneous fluidization regimes along the bed. Keywords: conical distributor design, fluidized bed, particle distribution, particle size, particle trajectory 1. Introduction Fluidized bed (FB) has been under research for a long time, and it has been used for various industries because of the high mixing and contact surface area between the particles and the fluidization fluid, which lead to high mass and heat transfer (Janvijitsakul & Kuprianov, 2008). The variety of fluidized beds encountered in commercial operation is enormous and includes powders having mean sizes as small as 15μm and large as 6mm, bed diameters from 0.1 to 10m, bed depths from a few centimeters to 10m and gas velocities from 0.01 to 3m/s or even as high as 10m/s for recirculating high velocity beds. The behavior of particulate solid in fluidized beds depends largely on a combination of their mean particle size and density, and it has become increasingly common to discuss fluidized systems in relation to the so-called Geldart fluidization (Ihsan Hamawand, 2004, Ihsan Hamawand, 2009). The minimum fluidization velocity is very important parameter in a fluidized bed process; it depends directly to the weight of the particle, where it increases with increase in particle weight. When gas is passed upwards through a packed bed unrestrained at its upper surface, the pressure drop increases with gas velocity until, on the microscopic scale, the drag on an individual particle exceeds the force exerted by gravity or, on the macroscopic scale, the pressure drop across the bed equals the weight of the bed per unit area (Ihsan Hamawand, 2004). One of the FB design is the conical fluidized bed, introduced in industries like combustion of biomass to produce energy (Janvijitsakul and Kuprianov, 2008; Kuprianov et al., 2006; Kuprianov et al., 2005; Permchart and Kuprianov, 2004), and agglomeration of particles in pharmaceutical application to modify their physical properties, size, shape, density and porosity (Jimenez et al., 2006; Wormsbecker et al., 2005, 2009; Chaplin et al., 2005). Conelike bunks have been connected broadly in different procedures, for example, the covering, drying and granulation of particulate materials and immobilized wastewater treatment and microorganism forms. In a cone shaped couch, where the cross area increment with the cot tallness, higher speed is kept up at the lower piece of the segment, making it conceivable to