Effect of Biodegradable Binder Properties and Operating Conditions on Growth of Urea Particles in a Fluidized Bed Granulator

Abstract

Granulation is an important step during the production of urea granules. Most of the commercial binders used for granulation are toxic and non-biodegradable. In this study, a fully biodegradable and cost-effective starch-based binder is used for urea granulation in a fluidized bed granulator. The effect of binder properties such as viscosity, surface tension, contact angle, penetration time, and liquid bridge bonding force on granulation performance is studied. In addition, the effect of fluidized bed process parameters such as fluidizing air inlet velocity, air temperature, weight of primary urea particles, binder spray rate, and binder concentration is also evaluated using response surface methodology. Based on the results, binder with higher concentration demonstrates higher viscosity and higher penetration time that potentially enhance the granulation performance. The viscous Stokes number for binder with higher concentration is lower than critical Stokes number that increases coalescence rate. Higher viscosity and lower restitution coefficient of urea particles result in elastic losses and subsequent successful coalescence. Statistical analysis indicate that air velocity, air temperature, and weight of primary urea particles have major effects on granulation performance. Higher air velocity increases probability of collision, whereby lower temperature prevents binder to be dried up prior to collision. Findings of this study can be useful for process scale-up and industrial application.

Optimization of fluidized bed agglomeration process for developing a blackberry powder mixture

“…In general, the results obtained show that the agglomeration process improves the rehydration properties for what was found at BPM, suggesting a higher capability to counteract surface tension at the solid-liquid interface, and therefore facilitate that ABPM is wet faster [ 38 ]; on the other hand, there is a synergistic effect with the composition of ABPM, which are mainly made up of carbohydrates and polar molecules such as An, organic acids, vitamins, among others [ 39 ], which favour the dissolution of solid bridges between particles [ 40 ]. The literature does not report investigations in berry-type fruits in agglomerated food products.…”

Revestimentos de materiais por Leito Fluidizado e Leito de Jorro: um estudo comparativo

“…O ar de atomização também facilita a evaporação do revestimento solvente. Tal evaporação aumenta a viscosidade das gotículas e reduz a dispersão e coalescência quando o material do núcleo interage (Zhalehrajabi, et al, 2019 ). A aplicação compreende uma ampla gama de produtos alimentícios de alta qualidade, que incluem ingredientes funcionais e produtos adicionais, conservantes, substâncias fortificantes, compostos aromáticos e especiarias (Chen, et al, 2009).…”

Industrial Verification and Research Development of Lime–Gypsum Fertilizer Granulation Method

“…Such a liquid is most often water [38] or aqueous solutions of substances such as gelatin, polymers, resins, starch, glues, sugars, salts, or molasses [39,40]. This type of process can be carried out in one-stage and two-stage technology and may also apply to products other than agricultural fertilizers [41,42]. There is a known method [43] of agglomeration of dust raised from kilns intended for the firing of cement clinker, fillers, powdery fertilizers, ashes from electrostatic precipitators, and dyes, using drum or disc granulators in which agglomeration by surrounding occurs and which is carried out in two stages.…”