A simplified approach to the model development and scale-up of a packed bubble column reactor from pilot semi-batch mode to continuous commercial operation has been presented. This is illustrated by choosing the reaction of ethynylation of formaldehyde to 1,4-butynediol for which correct reaction mechanism is difficult to postulate in the compelling safety limitations. The apparent reaction kin...

Abstract The gas-liquid-solid mixing characteristics in slurry bubble column were studied using the CFD-PBM model under different cross section coverage ratios of tubes. research shows that with increase proportion area vertical tube, flow field tends to be stable, liquid phase rate becomes faster, and large-scale circulation strengthens, resulting decrease gas holdup. As increases, distributio...

Computer simulations of bubble oscillations in water have revealed that characteristics of bubbles depend on types of sonochemical reactors. When the acoustic amplitude is large at 20 kHz, the bubble content when a bubble collapses is mostly water vapor and the temperature inside a bubble at the collapse is relatively low. On the other hand, when the acoustic amplitude is relatively low, the bu...

Mercaptans are commonly present in petroleum products. Their foul odor and highly corrosive nature make them the most undesirable sulfur compounds so they should be removed because of environmental issues. Merox process is used for oxidation of mercaptans to disulfide using air in the presence of alkaline solution and Merox catalyst. In this paper, due to lack of information about the kinet...

mercaptans are commonly present in petroleum products. their foul odor and highly corrosive nature make them the most undesirable sulfur compounds so they should be removed because of environmental issues. merox process is used for oxidation of mercaptans to disulfide using air in the presence of alkaline solution and merox catalyst. in this paper, due to lack of information about the kinetic o...

Gas holdup and bubble size are important parameters for simulation and designing in bubble column reactors. Because based on these parameters, the available gas-liquid interfacial area is defined for mass transfer. In this paper, the results of applying magnetic fields on the velocity field and volume fraction of gas holdup are reported. Hydrodynamics of the bubble column in the reactors is inv...

biodegradation kinetics of 4-nitrophenol (pnp) in aqueous solution by a gram negative soil bacterium, ralstoniaeutropha was firstly studied in a small scale batch reactor. the degradation of pnp was evaluated at initial pnp concentrations ranging from 3 mg/l to 14 mg/l. the rate of pnp consumption by the bacterium culture was modeled using monod and contois kinetics in batch condition. pnp degr...

In this paper, a CFD model of syngas flow in slurry bubble column was developed. The model is based on an Eulerian-Eulerian approach and includes three phases: slurry of solid particles suspended in paraffin oil and syngas bubbles. Numerical calculations carried out for catalyst particles, bubble coalescence and breakup included bubble-fluid drag force and interfacial area effects. Also, the ef...