The main advantage of a fluidized bed is its capability in excellent gas-fuel mixing. However, due to the lacks of gas radial momentum, its lateral mixing of gas-solid is not adequate. Therefore, this research is focused on fluidized bed hydrodynamics enhancement using the modified gas distributor plate design. For getting an optimum fluidized bed hydrodynamics prediction, three different class...

Effect of scale on the hydrodynamics of gas-solid fluidized beds was investigated in two fluidized beds of 152 mm and 78 mm in diameter.  Air at room temperature was used as the fluidizing gas in the bed of sand particles. The Radioactive Particle Tracking (RPT) technique was employed to obtain the instantaneous positions of the particles at every 20 ms of the experiments. These data were u...

effect of scale on the hydrodynamics of gas-solid fluidized beds was investigated in two fluidized beds of 152 mm and 78 mm in diameter.  air at room temperature was used as the fluidizing gas in the bed of sand particles. the radioactive particle tracking (rpt) technique was employed to obtain the instantaneous positions of the particles at every 20 ms of the experiments. these data were used ...

Fixed fluidized bed reactor is widely used to evaluate the crackability of heavy oils and the activity of catalysts. To understand the hydrodynamics, reaction kinetics and thermodynamics in conventional and modified fixed fluidized bed reactors, the computational fluid dynamics method, energy-minimization multi-scale-based two-fluid model coupled with a six-lump kinetic model was used to invest...

The design of furnaces and boilers for solid fuels is supported increasingly by powerful softwares and ever faster computers. A round-robin over the most important CFD (computational fluid mechanics) models and softwares currently available shows, however, that numerical procedures for particle/turbulence interactions are not (yet) very advanced. Particle/fluid interphase slip is considered, bu...

the mixing behavior of the gas-liquid phase in three loop bioreactors was investigated. a gas-induced external airlift loop bioreactor (ealb), a forced-liquid vertical tubular loop bioreactor (vtlb) and a forced-liquid horizontal tubular loop bioreactor (htlb) were used for mixing studies as well as biomass production from natural gas. the effect of design parameters, riser to downcomer cross s...

An experimental study is performed on air-liquid-particle mixing, resulting from an air-particle mixture injected into a liquid flowing through a slender ladle. Flow visualization combined with image processing is employed to investigate the bubble and particle behavior at the nozzle outlet. Effort is directed to particle discrimination in both the liquid and the bubbles to determine particle d...

The mixing behavior of the gas-liquid phase in three loop bioreactors was investigated. A gas-induced External Airlift Loop Bioreactor (EALB), a forced-liquid Vertical Tubular Loop Bioreactor (VTLB) and a forced-liquid Horizontal Tubular Loop Bioreactor (HTLB) were used for mixing studies as well as biomass production from natural gas. The effect of design parameters, riser to downcomer cro...

CFB reactors are increasingly used for both gas catalytic and gas/solid reactions. Gas flow patterns in the riser are important in their design and subject of the present research. A literature review on the gas mixing in the riser highlights the contradictory results of previous investigations for CFB risers: some investigators neglected back-mixing of gas, whereas others report a considerable...