To investigate the hydrodynamic behaviour of industrial scale bubbling fluidised bed reactors, a 3D Discrete Bubble Model (DBM) has been developed. In the DBM, an Euler-Lagrange model, the bubbles are treated as discrete elements and the bubble trajectories are tracked individually, while the emulsion phase is considered as a continuum and is described with the continuity and Navier-Stokes equa...

One approach to reduce nutrient losses from livestock farms is to apply biological waste treatment systems such as biological nitrogen (N) removal or enhanced biological phosphorus (P) removal (EBPR) to reduce the nutrient content of land-applied waste. The EBPR process takes advantage of the ability of P-accumulating organisms (PAOs) to sequester excess P as polyphosphate granules in their cyt...

The effect of impeller speed on the air flow in a selfaerated Denver laboratory flotation cell was investigated using computational modelling. Air is induced into the slurry by the impeller’s rotating action. The rate of air flow is determined by the suction pressure created by the impeller, the hydrostatic head of the slurry and the frictional losses along the delivery shaft from the inlet val...

Many industrial processes, particularly in the food industry, produce slurriesor wastewaters containing high concentrations of biodegradable organicmaterials. Before these contaminated wastewaters can be dischargedthe concentration of these pollutants must be reduced. A method which has beenextensively employed to remove biodegradable organic matter is biologicaltreatment. In this process the w...

Abstrati-An experimental study of the catalytic hydrogenation of 2,4_dinitrotoluene (DNT) in a miniinstallation with a continuously operated stirred three-phase slurry reactor and an evaporating solvent is discussed_ Some characteristic properties of the reactor system and the influence of the operating parameters on the performance of the reactor are illustrated. The experimental results are c...

In order to elucidate and quantify nitrogen transformations occurring during aerobic treatment of pig slurry, two laboratory experiments were carried out with contrasting levels of aeration, high level (experiment 1) and low level (experiment 2) of aeration. During these experiments, after reaching steadystate conditions, a single pulse of NO3 -N tracer was added directly to the reactor. When n...

Swarm Optimisation and Genetic Algorithms applied to a Three-Phase Slurry Catalytic Reactor Mylene C. A. F. Rezende, Caliane B. B. Costa, Delba N. C. Melo, Adriano P. Mariano, Eduardo C. Vasco de Toledo, Rubens Maciel Filho School of Chemical Engineering University of Campinas, UNICAMP P.O. Box 6066, Zip Code 13083-970, Campinas-SP, Brazil E-mail address: [email protected] Petrobras S...

In recent years, there has been a growing interest in bioreactors, which utilise immobilised enzymes and cells in order to improve the bioprocess productivity. In fact, there are many specific advantages of the immobilised systems in comparison with the more conventional systems, in which the bio-agents are suspended freely (cells) or dissolved in a bulk aqueous medium (enzymes): • high cell de...