RESUMEN
The concept of anaerobic ammonium oxidation (ANAMMOX) is presently of great interest. The functional bacteria belonging to the Planctomycete phylum and their metabolism are investigated by microbiologists. Meanwhile, the ANAMMOX is equally valuable in treatment of ammonium-rich wastewaters. Related processes including partial nitritation-ANAMMOX and completely autotrophic nitrogen removal over nitrite (CANON) have been developed, and lab-scale experiments proved that both processes were quite feasible in engineering with appropriate control. Successful full-scale practice in the Netherlands will accelerate application of the process in future. This review introduces the microbiology and more focuses on application of the ANAMMOX process.
Asunto(s)
Bacterias Anaerobias , Metabolismo , Reactores Biológicos , Nitritos , Metabolismo , Nitrógeno , Metabolismo , Oxidación-Reducción , Compuestos de Amonio Cuaternario , Metabolismo , Eliminación de Residuos Líquidos , Purificación del Agua , MétodosRESUMEN
The characteristics of gas-liquid mass transfer of three-phase system comprising air, tap water/wastewater, and hollow glass beads were studied in a laboratory-scale inverse turbulent bed reactor. The influence of operational factors and liquid property on volumetric liquid-phase mass transfer coefficient kLa was investigated under the conditions of superficial gas velocity (0.53mm xs(-1) - 10mx s(-1) solid hold-up (0 - 0.3), and superficial liquid velocity (0 - 0.2mm x s(-1)). The results showed that the coefficient value was 0.0456 - 1. 414min -, which increased with superficial gas velocity and liquid velocity. The coefficient attained the maximum value at solid hold-up of 0.05 - 0.08. Compared with the coefficient value in tap water, that in synthetic wastewater and industrial wastewater is decreased by 39.0% and 50.9%, respectively. These data have provided a basis for the process analysis and mathematical simulation of inverse turbulent bed reactor.
Asunto(s)
Algoritmos , Biodegradación Ambiental , Reactores Biológicos , Simulación por Computador , Gases , Química , Metabolismo , Cinética , Modelos Químicos , Reproducibilidad de los Resultados , Temperatura , Eliminación de Residuos Líquidos , Métodos , Agua , Química , Metabolismo , Microbiología del Agua , Contaminantes Químicos del Agua , Química , Metabolismo , Purificación del Agua , MétodosRESUMEN
The effects of operational variables and reactor configurations (e.g. diameter of draft tube and the number of static mixers) on energy loss in modified airlift bioreactor were investigated at the first time. The results showed that improving the structure of draft tube could reduce energy loss in the bioreactor. When the diameter of draft tube and the number of static mixers were 4.0cm and 39, respectively, the total energy loss in the modified bioreactor was the least among all the configurations and 23.6% less than that of the conventional counterpart at the same air flowrate. The energy consumption for aeration was the smallest (43.9% less than that of the conventional counterpart) when the diameter of draft tube and the number of static mixers were 5.5cm and 13, respectively. The highest energy dissipation (70% - 80%) occurred in the riser, the bottom zone (about 20%) took the second place and the separator (less than 10%) took the third place. The energy dissipation in the downcomer was neglectable under the conditions in the research. When the energy loss per unit volume was considered, bottom zone stood the first place. It was implied that the riser was the most important zone to cut down the energy loss of the bioreactor and some attention should also be paid to the bottom zone.