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What is oxygen transfer rate in bioreactor?

What is oxygen transfer rate in bioreactor?

The efficiency of mass transfer increases with increasing surface area available for transfer. The oxygen transfer rate (OTR) through an interface is calculated as the multiplicative product of the mass transfer coefficient, the specific transfer area, and the concentration driving force.

What is Standard oxygen Transfer rate?

The Standard Oxygen Transfer Rate (SOTR) is the rate at which the SOR is transferred in tap water at 20°C and zero DO. The Actual Oxygen Transfer Rate (AOTR or OTRf) is the rate at which AOR is transferred under field conditions.

How is kLa calculated?

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.

How do you calculate Standard oxygen Transfer Efficiency?

The standard oxygen transfer rate (SOTR, g/m3 · s) is shown to be related to EI through a second-degree equation: SOTR = −11.5 EI2 + 2.27 EI (r2 = 0.951). The model applies over a wide range of diffuser types, diffuser densities, tank dimensions, and specific air flows.

How do you calculate the amount of oxygen needed?

Oxygen requirements vs F:M ratio. Where nitrification is to be carried out, 4.3 kg/day of oxygen per kg ammonia oxidized shall be added to the figure calculated by equation 14.5….Oxygen requirements.

Aeration System Oxygenation Efficiency (kg/kWh)
Horizontal mechanical surface aerator 1.2–2.4

What are the factors affecting the oxygen transfer rate?

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.

How do you increase oxygen transfer rate in bioreactors?

For a successful aerobic cultivation, a good oxygen transfer is vital. It can be increased by: Creating a bigger surface of gas bubbles (kLa) by increasing gas flow and stirrer speed and by adding baffles. Creating a higher O2 concentration gradient by adding O2 to gasmix and increasing the pressure.

What is KLa oxygen?

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 KLa requirement is pure O2 is used in the gas and the DO is maintained at 50% air saturation?

Here, the theoretical KLa required is 4.67 h-1. This value is given for DO set-point at 50% with a gas flow of 30 mL/min Air and 200 mL/min O2. To get this KLa in the bioreactor, use the relationship between the KLa and the liquid flow rate through the fixed-bed (Figure 3).

How do you calculate the actual oxygen requirement for an aeration tank?

Hence O2 required 350/0.20 =1750 kg/day. one more point to be consider the Depth of aeration Tank, suppose it is 4 metre depth select 0.5 or 0.6 kg/cm² in blower side.

How do you calculate oxygen requirements for an aeration tank?

In general the Standard Oxygen Requirement (SOR) is in between 1.5 2.5 times the AOR. The quantity of the biomass required depends strongly on the load and the effluent quality to be met. Once the quantity of the biomass is known, the oxygen command (OC) can be determined and the aeration tank can be designed.