What is oxygen transfer coefficient?
What is oxygen transfer coefficient?
The kLa (Volumetric Mass Transfer Coefficient) and the OTR (Oxygen Transfer Rate) detail how efficient oxygen is transferred from the gas bubbles into the bioreactor medium, i.e. how much oxygen is available for the cultivated biomass.
What is volumetric oxygen transfer coefficient in bioreactor?
transfer coefficient in a bioreactor system and provide. estimates of the volumetric microbial oxygen uptake rate. and the average oxygen saturation concentration at the. gas-liquid interface. The errors on these parameters are.
What are the factors that affect oxygen transfer in a bioreactor?
Key variables that impact kLa values
- Gas bubble size. When gas bubble size decreases, surface area and gas residency time increases, causing bubbles to stay in the culture longer.
- Mixing.
- Air flow rate.
- Properties of the liquid or medium.
What are the different methods of the measurement of the oxygen transfer coefficients in a bioreactor system?
There are many techniques for measuring oxygen concentration and OTR in bioreactors. Zirconia, electrochemical, infrared, ultrasonic and laser cells are used to measure oxygen concentration in the liquid medium. Optical sensors are better alternatives to measure oxygen concentration in small bioreactors.
How do you measure kLa in a bioreactor?
If we assume steady state and no accumulation of oxygen inside the bioreactor, under such conditions OTR=OUR. So, kLa*(C*-CL)=OUR. So, kLa=OUR/(C*-CL) and OUR is generally calculated as OUR=qO2*Cx. Therefore, kLa=qO2*Cx/(C*-CL), where qO2 is the specific oxygen uptake rate of oxygen and Cx is the biomass concentration.
What is the importance of kLa?
A constant kLa ensures equal oxygen transfer independent of physical differences between each scale. kLa is influenced by factors such as bioreactor geometry, gas flow, superficial gas velocity, impeller type and speed, and power input for mixing per unit reaction volume.
What is the unit of volumetric oxygen transfer coefficient?
ADVERTISEMENTS: Read this article to learn about Volumetric Oxygen Transfer Coefficient (KLa)! where a is the amount of surface area per unit volume. In this relation, the volumetric oxygen transfer coefficient, KLa, has the units of m mol, of O2/ml.
What does kLa depend on?
The values of kLa are affected by many factors, such as geometrical and operating characteristics of the reactor (type of impeller, the geometry of the bioreactor, the agitation speed and the air flow rate), media composition and properties, concentration and microorganism’s morphology and biocatalyst’s properties [3].
What is kLa in bioreactor?
kLa is a gas transfer coefficient, a measurement of the capacity of the bioreactor to transfer oxygen into the cultures. kLa is influenced by factors such as bioreactor geometry, gas flow, superficial gas velocity, impeller type and speed, and power input for mixing per unit reaction volume.
How do you calculate kLa?
So, kLa=OUR/(C*-CL) and OUR is generally calculated as OUR=qO2*Cx. Therefore, kLa=qO2*Cx/(C*-CL), where qO2 is the specific oxygen uptake rate of oxygen and Cx is the biomass concentration.
