Mass transfer studies are carried out in a bubble column with an internal diameter of 14 cm and various static liquid heights. The mass transfer coefficient is evaluated by using an oxygen sorption method. A model considering the gas holdup flushing and the sensor response is used. The interfacial mass transfer area is determined according to the measured bubble size distribution. The liquid-si...

Surface transfer and bubble transfer both contribute significantly to oxygen transfer in a diffused aeration system. In the present study, liquid-film-forming apparatus is successfully developed on a laboratory scale to improve considerably the surface transfer via the unique liquid film transfer technique. The experimental results show that the volumetric mass transfer coefficient for liquid-f...

An upflow microbial fuel cell (UMFC) system with a U-shaped cathode inside the anode chamber was developed and produced a maximum volumetric power of 29.2 W/m3 at a volumetric loading rate of 3.40 kg COD/(m3 day) and an operating temperature of 35 degrees C while feeding sucrose continuously. The Coulombic efficiency decreased from 51.0% to 10.6% with the increase in the volumetric loading rate...

this paper presents theoretical and numerical state-of-the-art information in the field of hygro-thermo-mechanical deformation simulation in structural concrete. the aspects discussed include coupled hygro-thermo-mechanical performance of porous materials including concrete, multi-scale simulation of concrete properties especially the volumetric and structural deformation performance, and the m...

a model describing the main processes occurring in the uasb reactor was developed; in orderto maintain simplicity and applicability of the model, only the fundamental aspects were considered. in themodel, the reactor is divided in several well-stirred reactors coupled in series and it comprises substratedegradation, biomass growth and the reactions that take place within the granules. the impor...

Shell and Tube heat exchangers are the heat exchangers that are most widely used in industries and for other commercial purposes. There are many techniques that have been utilized to enhance the heat transfer performance of the shell and tube heat exchangers. Air bubble injection is one of the promising and inexpensive techniques that can create turbulence in the fluids resulting in to enhancem...

Membrane contactor using amine based absorbents is an efficient technology for CO2 separation from gaseous mixtures. A novel porous polysulfone (PSF) flat membrane was prepared via non-solvent phase inversion method. The PSF membrane was modified by adding polyvinyl pyrrolidone (PVP) to the dope solution. The fabricated membrane was used in the serpentine flow field contactor module for CO2 abs...

A population balance model is considered for the description of mass transfer in liquidliquid dispersions in a mechanically agitated vessel operated continuously. The dispersions considered are of low dispersed phase fraction in which coalescence processes may be assumed to be negligible. The model incorporates the dynamic nature of breakage processes among the droplet population together with ...

The performance of a forced-liquid Vertical Tubular Loop Bioreactor (VTLB), a forced-liquid Horizontal Tubular Loop Bioreactor (HTLB) and a gas-induced External Airlift Loop Bioreactor (EALB) were compared for production of biomass from natural gas. Hydrodynamic characteristics and mass transfer coefficients were determined as functions of design parameters, physical properties of gases as ...