Oxygen uptake rate

A plot of the specific respiration rate ( 02 versus the specific growth rate coefficient [L is linear, with the intercept on the ordinate equal to the oxygen uptake rate for cell maintenance. A formulation of this is ... 

A useful index of process performance is the oxygen uptake rate, OUR, that is calculated from the difference in oxygen concentration of the inlet air and the exiting gas. Also important is the respiration ratio defined as the carbon dioxide evolved divided by the oxygen consumed. 

Livingston, A.G., Gikas, P., Viability of immobilised cells use of specific ATP levels and oxygen uptake rates.. Immobilised Cells Basics and Applications, Ed. Wijfells, R.H., Buitelaar, R.M., Bucke, C., Tramper, J., Progess in Biotech. 11, pp.264-271, 1996. 

Oxygen uptake rate (OUR) The actual rate at which oxygen utilization takes place and is given by ( o/Yo2) C, , where p is specific growth... 

Oxygen uptake Rate of oxygen transfer from air resident in the pulmonary... 

In biochemical engineering processes, measurement of dissolved oxygen (DO) is essential. The production of SCP may reach a steady-state condition by keeping the DO level constant, while the viable protein is continuously harvested. The concentration of protein is proportional to oxygen uptake rate. Control of DO would lead us to achieve steady SCP production. Variation of DO may affect retention time and other process variables such as substrate and product concentrations, retention time, dilution rate and aeration rate. Microbial activities are monitored by the oxygen uptake rate from the supplied ah or oxygen. 

A strain of Azotobacter vinelandii was cultured in a 15 m3 stirred fermenter for the production of alginate. Under current conditions the mass transfer coefficient, kLa, is 0.18 s. Oxygen solubility in the fermentation broth is approximately 8 X 10 3 kgm-3.9 The specific oxygen uptake rate is 12.5 mmol g 1 h. What is the maximum cell density in the broth If copper sulphate is accidentally added to the fermentation broth, which may reduce the oxygen uptake rate to 3 mmol g 1 h 1 and inhibit the microbial cell growth, what would be the maximum cell density in this condition ... 

Let us assume the solubility of oxygen does not affect on C or kLa, the factor affected on the oxygen uptake rate that is 12.5/3 = 4.167, then xmm is ... 

Gas holdup Inducers Specific oxygen uptake rate... 

Wang et al.2 and Najafpour et al.3A worked with immobilised microbial cells of Nitrobacer agilis, Saccharomyces cerevisiae and Pseudomonas aeruginosa in gel beads, respectively. They found separately that the cells retained more than 90% of their activity after immobilisation by using specific oxygen uptake rate (SOUR) [mg 02g 1 (dry biomass) h 11 as the biomass activity indicator. Such differences in immobilised biomass and activity between free and immobilised biomass activities depend strongly on the particular characteristics of the microbial systems and their interaction with the support matrix. 

If you aerate a bioreactor, power consumption is much less than a non-aerated bioreactor. Oxygen transfer rate, OTR 6 X 10 3 kgm-3 Oxygen uptake rate, OUR 0.65 mmol 02 kg 1 cell Specific growth rate, umax 0.5 h 1... 

Equation 17.7 suggests that the oxygen uptake rate (q02xv) can be obtained by simple linear regression of Co2(t) versus time. This is shown in Figure 17.5 where the oxygen uptake rate has been estimated to be 0.0813 nig/L-min. 

Figure 17.5 PULSAR Determination of Oxygen Uptake Rate by Simple Linear Least Squares During the Gassing-out Period...

The microbial activity of wastewater under anoxic conditions is lower compared with aerobic conditions (Abdul-Talib et al., 2001). This is important to consider, because a low nitrate uptake rate (NUR) compared with the oxygen uptake rate (OUR) in units of electron equivalents means a reduced transformation rate of the most biodegradable fractions of the organic matter. As mentioned under the point on injection of air, this may have implications in terms of treatment. Furthermore, a relatively low NUR value also has operational advantages because of a reduced demand for nitrate to suppress sulfide formation. 

Oxygen Uptake Rate Measurements of Bulk Water... 

A bulk water oxygen uptake rate (OUR) measurement is performed as a laboratory study. It will be separately dealt with because of its fundamental importance for sewer process studies. 

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