What is kLa oxygen?

What is kLa oxygen?

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 does oxygen availability affect kLa value?

Higher oxygen availability drives kLa increases. Increasing oxygen supply to a bioreactor drives this availability and can be controlled by modifying concentration (air vs O2 enrichment) and volumetric flow.

How is kLa calculated?

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 unit of kLa?

Explanation: In this relation, the volumetric oxygen transfer coefficient, kLa, has the units of mmol, of O2/ml. h. unit concentration gradient. Using the proper concentration units, kLa has the unit of reciprocal of time (i.e., time-1).

What is kLa fermenter?

2.4. Effects of Agitation and Aeration on kLa on Bench Scale. The volumetric oxygen transfer coefficient (kLa) represents the capacity of oxygen supply and transfer in the fermentor, which is related with agitation speed, aeration rate, geometrical characteristic of fermentor and rheological character of medium [16].

What is dissolved oxygen do?

Overview. Dissolved oxygen (DO) is a measure of how much oxygen is dissolved in the water – the amount of oxygen available to living aquatic organisms.

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 the oxygen transfer rate?

Oxygen transfer is often the rate-limiting step in the aerobic bioprocess due to the low solubility of oxygen in the medium. The correct measurement and/or prediction of the volumetric mass transfer coefficient, (k(L)a), is a crucial step in the design, operation and scale-up of bioreactors.

What is dissolved oxygen meter?

Dissolved oxygen meters are designed to measure the amount gaseous oxygen dissolved in water. Dissolved oxygen (DO) is an important indicator of water quality. The amount of dissolved oxygen that water is capable of holding varies from about 8 to 14 mg/L depending upon the temperature of the water.

What is normal dissolved oxygen?

Healthy water should generally have dissolved oxygen concentrations above 6.5-8 mg/L and between about 80-120 %.

What is KLa mass transfer?

How do you calculate oxygen consumption?

The best fitting formula is expressed as: VO2(ass) = (157.3 x BSA + 10.0 x Sex – 10.5 x In Age + 4.8) ml. min-1, where ln Age = the natural logarithm of the age. This formula was validated prospectively in 60 patients.