This work is aimed at modeling the heat transfer mechanism in a fluidized bed of grass seeds (Brachiaria brizantha) for supporting further works on simulating the drying of these seeds in such a bed. The three-phase heat transfer model, developed by Vitor et al. (2004), is the one used for this proposal. This model is modified to uncouple one of the four adjusted model parameters from the gas t...

Simple transport models predict that the distance organisms drift downstream in rivers is determined by their settling velocity (ws), the release height (zr), and the stream velocity (U). Unfortunately, empirical evidence is lacking on whether and how factors such as ws affect mussel larvae dispersion in rivers under natural turbulent conditions. The main goal of this study was to examine how U...

Expanded bed adsorption chromatography (EBAC) is a single pass operation that has been used as primary capture step in various protein purifications. The most common problem in EBAC is often associated with successful formation of a stable fluidized bed during the absorption stage, which is critically dependent on parameters such as liquid velocity, bed height, particle (adsorbent) size and den...

Rigid chromatography resins, such as controlled pore glass based adsorbents, offer the advantage of high permeability and a linear pressure-flow relationship irrespective of column diameter which improves process time and maximizes productivity. However, the rigidity and irregularly shaped nature of these resins often present challenges in achieving consistent and uniform packed beds as formati...

This article describes the bed expansion characteristics of a down-flow anaerobic fluidized bed reactor treating a synthetic wastewater. Experiments were carried out in a 0.08 m diameter and 1 m length PVC column. The carrier used was ground perlite (an expanded volcanic rock). Particles characteristics were 0.968 mm in diameter, specific density of 213 kg x m-3 and Umf (minimal fluidization ve...

bubble column reactors are used in a wide variety of applications such as multiphase bioreactors, catalytic slurry reactors, and absorption processes. the superficial gas velocity-gas holdup relationship and transition point are two important parameters for characterizing the hydrodynamics of a bubble column reactor. in this study, systematic investigation of a nitrogen - water - glass beads bu...

the used activated carbon was derived from pine-cone and was used for the removal of acid black 1(ab1) and acid blue 113(ab113) dyes. a batch sorption study was carried out in order to obtain optimum isotherm model. the study showed the best fit of the adsorption isotherm data was obtained using the langmuir model for both dyes. the monolayer maximum saturation capacities of ab1 and ab113 dyes ...

Introduction: A major concern of human being is accumulation and toxicity of heavy metals in their body. Copper is a heavy metal ion that in concentration of 2 mg/l can cause numerous complications. Different treatment methods have been proposed for removing metals from contaminated water by researchers. Among these methods, sorption seems a better method with high removal efficiency. In this s...

Packed open-cell foams are proposed as an alternative to standard packed bed configuration commonly adopted for the adsorption columns of a temperature swing process. In this contribution, heat transfer in column with foam is investigated by experimental and modeling analysis, comparison bed. The introduction allows more rapid transitions substantial reduction gradients within impact enhancemen...

The phenomenon of dispersion (transverse and longitudinal) in packed beds is summarized and reviewed for a great deal of information from the literature. Dispersion plays an important part, for example, in contaminant transport in ground water flows, in miscible displacement of oil and gas and in reactant and product transport in packed bed reactors. There are several variables that must be con...