This paper presents the numerical investigation of the effects of the general bed characteristics such as superficial gas velocities, bed temperature, bed heights and particle size, on the direct synthesis in a 3D fluidized bed reactor. A 3D model for the gas flow, heat transfer, and mass transfer was coupled to the direct synthesis reaction mechanism verified in the literature. The model was v...

A mathematical model for the fluidization of polydisperse suspensions is developed. The stationary concentration configurations for a given fluidizing velocity are analyzed and a mixing condition for bed inversion is derived. A central finite difference scheme is applied to the simulation of the fluidization of a bidisperse suspension. The numerical simulations agree with the experimentally rep...

The aim of this work is to study coal steam gasification with various methods in-core treatment in FB using a newly developed thermodynamic calculation method. A calculational subbituminous non-catalytic was carried out four different single-vessel multisectional fluidized-bed gasifiers. semi-empirical model based on the entropy maximization method and “restricted equilibria” previously obtaine...

T he concept of chromatography in Expanded Bed Adsorption (EBA) was first proposed in early 90s. The initial advantage of the idea was to be able to directly process particulate containing biological feedstocks for target products, while still maintaining sufficiently high separation efficiency that is usually enjoyed only by the traditional chromatography columns. EBA could potentially replace...

P.Ragothaman,[email protected] Dr.N.V.Mahalakshmi,[email protected] Institute for Energy Studies, Anna University, Chennai-25,Tamilnadu, India. P.sudhakar,[email protected] Abstract Circulating fluidized bed reactors are widely applied in industry for power generation in boilers and gasifier. Computational Fluid dynamics modeling of hydrodynamics and heat transfer can be an effe...

Fluidized beds can be used to gasify biomass in the production of producer gas, a flammable gas that can replace natural gas in process heating. Modeling these reactors with computational fluid dynamics (CFD) simulations is advantageous when performing parametric studies for design and scale-up. From a computational resource point of view, two-dimensional simulations are easier to perform than ...

In this paper, water content from celery, corn, and sour cherry were removed through tunnel, fluidized bed, and fluidized bed with microwave dryers. One day before performing the experiments, the fruits were put into a refrigerator and were ground into slices with average dimensions of 5×8×8 mm. For each experiment, 40 g of the samples were inserted in dryers. Moisture content in the samples wa...

Low-temperature gasification of black liquor is a new alternative to the conventional Tomlinson recovery boiler for recovering pulping chemicals and energy from black liquor in pulp and paper mills. This process can be carried out in a fluidized bed based on steam reforming at 600 C using indirect heat supplied via heat exchangers built into the fluid bed. As black liquor is injected into the b...

There is increasing interest in CO2 looping cycles that involve the repeated calcination and carbonation of the sorbent as a way to capture CO2 from flue gases during the carbonation step and the generation of a pure stream of CO2 in the oxyfired calcination step. In particular, attrition of the material in these interconnected fluidized bed reactors is a problem of general concern. Attrition o...