Oxygen exit rate

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. 

Fluorescence quantum-yield and lifetime measurements have established that oxygen penetrates micelles (Geiger and Turro, 1975). Entrance- and exit-rate constants have been determined for a cationic (CTAB) and an anionic (SLS) micelle system using I, S-dimethylnaphthalene as the fluorescing species (Hautala et al., 1973). Of general importance is that the solubility of oxygen is higher in the micelle than in the aqueous phase. 

Table 9.9. Oxygen entry rate (k ), exit rate (k ) and migration rate (x) determined on - ...

Consider the PCM furnace module of Appendix E. Assume that oxygen exit concentration C02 is the CV, air flow rate AF is the MV, and fuel gas purity FG is the D V. 

Oxygen is suppHed quite routinely to patients suffering impaired respiratory function as weU as in other situations where oxygen is deemed to be useflil. The pure oxygen, with humidification, is deHvered via a simple double tube (cannula) to a point just inside the nostrils where the 99.5% gas blends with the room air (21% O2), and is inhaled. The concentration of oxygen that reaches the lungs thus depends on the rate and volume of air inhaled and on the exit flow of oxygen from the cannula, usually one to six L/min. 

The common indices of the physical environment are temperature, pressure, shaft power input, impeller speed, foam level, gas flow rate, liquid feed rates, broth viscosity, turbidity, pH, oxidation-reduction potential, dissolved oxygen, and exit gas concentrations. A wide variety of chemical assays can be performed product concentration, nutrient concentration, and product precursor concentration are important. Indices of respiration were mentioned with regard to oxygen transfer and are particularly useful in tracking fermentation behavior. Computer control schemes for fermentation can focus on high productiv-... 

---