in this research, a cold model of internally circulating fluidized bed is investigated. the aim is to find the effects of some of the operating parameters on the performance of the reactor. experiments were carried out in a glass column (30 mm i.d. and 25 cm height) with a centrally located draft tube (11 mm i.d. and 5 or 7 cm height). the bed was loaded with white silica particles (dp = 0.15 -...

Spectral method based on POD are an effective approach for model reduction but variable boundary conditions are often a problem, since basis functions must satisfy boundary conditions at all times. In this work we introduce weak imposition of boundary conditions by means of a penalty method and apply the method to develop reduced order models of two different chemical reactors. A quantitative a...

−− The typical microbiological groups reported in literature under the experienced environmental conditions are present in the biofilm structure investigated on sand particles. This is concluded based on microorganism morphology analyzed by scanning electron microscopy. Methanosarcina sp. (acetate consumers) and filamentous microorganisms with morphology similar to Methanospirillum sp. (H2-util...

This paper focuses on the determination of the solid circulation of a CFB gasification system with a dual fluidized bed concept and the distribution of the solid hold up at different fluidization conditions. A mathematical model of the riser was designed and implemented in a model of a dual fluidized bed system. This model contains routines for calculation of each section of the dual fluidized ...

Kinetic study for different start up conditions of the anaerobic digestion of wastewater derived from the sago processing from tubers of tapioca (Mannihot utillisema) is discussed. The experiment is carried out with synthetic waste water using a tapered fluidized bed reactor. Mesoporous granulated activated carbon is used as a bacterial support. The kinetic model follows half order kinetics for...

The effect of hydraulic retention time (HRT) and organic loading rate (OLR) on biological hydrogen production was assessed using an anaerobic fluidized bed reactor fed with cassava wastewater. The HRT of this reactor ranged from 8 to 1 h (28 to 161 kg COD/m-d). The inoculum was obtained from a facultative pond sludge derived from swine wastewater treatment. The effluent pH was approximately 5.0...

A favorable microenvironment for biofilm growth on GAC particles was shown using green fluorescent protein (GFP) as a marker for a phenol degrading bacterium, Pseudomonas putida F1. The dispersion of P. putida F1 in a biofilm covering granulated activated carbon (GAC) particles was monitored and compared to a biofilm on non-activated granular carbon particles. Laser scanning confocal microscopy...

in a novel dual bed reactor fischer-tropsch synthesis was studied by using two diffrent cobalt catalysts. an alkali-promoted cobalt catalyst was used in the first bed of a fixed-bed reactor followed by a rutenuim promoted cobalt catalyst in the second bed. the activity, product selectivity and accelerated deactivation of the system were assessed and compared with a conventional single bed react...

Pretreatment of corncobs using torrefaction was conducted in an auger reactor at 250-300 °C and residence times of 10-60 min. The torrefied corncobs were fast pyrolyzed in a bubbling fluidized bed reactor at 470 °C to obtain high-quality bio-oil. The heating value and pH of the bio-oil improved when the torrefaction as pretreatment was applied; however, increasing bio-oil yield penalties were o...

Simulation of fluidized bed reactor (FBR) was accomplished for treating wastewater using Fenton reaction, which is an advanced oxidation process (AOP). The simulation was performed to determine characteristics of FBR performance, concentration profile of the contaminants, and various prominent hydrodynamic properties (e.g., Reynolds number, velocity, and pressure) in the reactor. Simulation was...