What is volumetric mass transfer coefficient?
The volumetric mass transfer coefficient (kLa) is a parameter that determines the rate at which a gaseous compound (e.g. O2 or CO2) can transfer between the gas phase and the liquid phase.
What is liquid mass transfer coefficient?
Liquid mass transfer or convection coefficient is a flow dependent parameter, which is evaluated by use of empirical and semiempirical correlations. One of the most well-known correlations for use in water treatment situations is the following (Chern and Chien, 2002):
What is volumetric oxygen transfer coefficient?
And the amount of bubble transfer area in a bioreactor or fermenter, an engineering parameter known as volumetric oxygen transfer coefficient, expressed by KLa, has been used to represent volumetric oxygen transfer coefficient as: where a is the amount of surface area per unit volume.
What do you mean by kLa?
unit concentration gradient. Using the proper concentration units, kLa has the unit of reciprocal of time (i.e., time-1).
What is gas liquid mass transfer?
In biological multiphase systems, mass transfer takes place between two liquid phases, between a liquid and a solid phase, or between a gas and a liquid phase.
What is diffusion coefficient in mass transfer?
The diffusion coefficient (or diffusivity) is a proportionality constant between the molar flux due to molecular diffusion and the gradient in the concentration of the species (or the driving force for diffusion).
Which of the following is are true about mass transfer coefficient of liquid?
9. Which of the following is true for mass transfer across liquid-liquid interface? Explanation: For mass transfer across liquid-liquid interface 1/Kx(2) = 1/KAkx(1) + 1/kx(2) holds true.
How is Schmidt number calculated?
The Schmidt number (Sc) is the ratio of the kinematic viscosity to the molecular diffusion coefficient, i.e., Sc= v/Dm.
How do you calculate oxygen transfer?
Oxygen Uptake Rate (OUR) Calculation d [O2] / d t (= OTR, oxygen transfer rate) is used to calculate the current oxygen consumption during a certain time period. So in order to calculate the OUR of the cells / microorganisms the kLa has to be known, estimated, or determined.
What is KLa mass transfer?
Mass transfer coefficient kL: describes the transport of oxygen and gas into the liquid phase. a: Gas-liquid exchange area per unit of liquid volume.
What is Henry’s law used for?
In physical chemistry, Henry’s law is a gas law that states that the amount of dissolved gas in a liquid is proportional to its partial pressure above the liquid. The proportionality factor is called Henry’s law constant.
Which of the following is true about rate of mass transfer in liquid?
Which of the following is true for mass transfer across liquid-liquid interface? Explanation: For mass transfer across liquid-liquid interface 1/Kx(2) = 1/KAkx(1) + 1/kx(2) holds true.
Is mass transfer coefficient the same as diffusion coefficient?
The main difference between mass transfer and diffusion is that mass transfer may or may not involve a concentration gradient whereas diffusion does involve the movement of a solute down a concentration gradient.
What is Schmidt number in mass transfer?
The Schmidt number is the ratio of the shear component for diffusivity viscosity/density to the diffusivity for mass transfer D. It physically relates the relative thickness of the hydrodynamic layer and mass-transfer boundary layer.
What is the volumetric mass transfer coefficient used for?
The volumetric mass transfer coefficient obtained from the empirical formula is used to estimate the enhancement factor due to chemical reaction. James R. Fair, Henry Z. Kister, in Encyclopedia of Physical Science and Technology (Third Edition), 2003 Enthalpy, Btu/lb mole (kJ/kmol) ( Fig. 12 and Eq. (33) only)
How do you calculate the mass transfer coefficient of a gas?
The combined mass transfer coefficients in Eqs. (10.30) and (10.31) can be used to define overall mass transfer coefficients. The overall gas-phase mass transfer coefficient KG is defined by the equation: (10.32)1 KGa = 1 kGa + m kLa. and the overall liquid-phase mass transfer coefficient KL is defined as:
What is convection coefficient in liquid mass transfer?
Liquid mass transfer or convection coefficient is a flow dependent parameter, which is evaluated by use of empirical and semiempirical correlations. One of the most well-known correlations for use in water treatment situations is the following (Chern and Chien, 2002 ):
What does kg MeAN in mass transfer coefficient?
where kG is the gas-phase mass transfer coefficient and kL is the liquid-phase mass transfer coefficient. To eliminate CAGi and CALi, we must manipulate the equations as discussed in Section 10.4.2.