Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The trac...Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The tracer used is a gel particle which resembles typical immobilized biocatalyst.The tracer trajectory is analyzed to extract relevant information for design purposes.The solid velocity field,turbulence parameters,dispersion coefficients,mixing times and flow transitions are determined and compared.The presence of foam significantly affects many quantified parameters,especially within the heterogeneous flow regime.The hydrodynamic stresses are reduced in the presence of foam,especially close to the disengagement.The dispersion coefficients also decrease,and the solid mixing time is only slightly affected by the presence of foam.Gas holdup,inferred both from RPT experiments and from gamma ray scanning,is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values.展开更多
Liquid-solid fluidized beds(LSFB)modeling validation is crucial for establishing design rules and monitor-ing tools.However,it generally relies on comparing global variables,which overlook dynamic features that influe...Liquid-solid fluidized beds(LSFB)modeling validation is crucial for establishing design rules and monitor-ing tools.However,it generally relies on comparing global variables,which overlook dynamic features that influence reaction outputs.This work aims to implement time series analysis tools to compare Radioactive Particle Tracking data with a simulation consisting of Computational Fluid Dynamics cou-pled with Discrete-Element Method.Experiments have been performed in a pilot-scale LSFB of calcium alginate spheres fluidized with a calcium chloride solution.The Diks'test indicates that the simulation can capture the LSFB behavior.It also allows diagnosing flow regime transitions from the simulation.Trends of solid dispersion coefficients and mixing times predicted by the simulation are in good agreement with the experiments.展开更多
基金Supported by the FONCyT(PICT2014-0704)CONICET(PIP1122015-0100902CO)Universidad de Buenos Aires(UBACyT 20020130100544BA)
文摘Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The tracer used is a gel particle which resembles typical immobilized biocatalyst.The tracer trajectory is analyzed to extract relevant information for design purposes.The solid velocity field,turbulence parameters,dispersion coefficients,mixing times and flow transitions are determined and compared.The presence of foam significantly affects many quantified parameters,especially within the heterogeneous flow regime.The hydrodynamic stresses are reduced in the presence of foam,especially close to the disengagement.The dispersion coefficients also decrease,and the solid mixing time is only slightly affected by the presence of foam.Gas holdup,inferred both from RPT experiments and from gamma ray scanning,is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values.
基金Financial support from Hogskolestiftelsen iÖster-botten(2804720/28600122)the Harry Schaumans Foundation(2804720/28002257)+2 种基金Suomen Kulttuurirahasto(00210970)CON-ICET(PIP1122015-0100902CO)Universidad de Buenos Aires(UBACyT 20020130100544BA)is gratefully acknowledged.
文摘Liquid-solid fluidized beds(LSFB)modeling validation is crucial for establishing design rules and monitor-ing tools.However,it generally relies on comparing global variables,which overlook dynamic features that influence reaction outputs.This work aims to implement time series analysis tools to compare Radioactive Particle Tracking data with a simulation consisting of Computational Fluid Dynamics cou-pled with Discrete-Element Method.Experiments have been performed in a pilot-scale LSFB of calcium alginate spheres fluidized with a calcium chloride solution.The Diks'test indicates that the simulation can capture the LSFB behavior.It also allows diagnosing flow regime transitions from the simulation.Trends of solid dispersion coefficients and mixing times predicted by the simulation are in good agreement with the experiments.
