Table I.
Typical DO transfer properties of various scale culture systems from process development to production.
| Class | Volume range | kLa range (h-1) | Refs. |
|---|---|---|---|
| Microwell plates (384) | 20–125 µL | Up to 140 | Duetz and Witholt (2004) |
| Microwell plates (96) | 100 µL to 2 mL | 20–250 | Islam et al. (2008) |
| Shaker flasks | 25 mL to 2 L | 10–180 | Maier and Büchs (2001) |
| Bench-scale STR | 100 mL to 1 L | Up to 400 | Gill et al. (2008) |
| 1–30 L | 60–360 | Özbek and Gayik (2001) | |
| Pilot scale STR | 30–2,000 L | 170–740 | Junker (2004) |
| 14,000–20,000 L | 340–380 | Junker (2004) | |
| Production scale STR | >20,000 L | Up to 1,800 | Nielsen et al. (2003) |
kLa values were chosen to reflect the ranges generally reported in the literature for culture of microbes.
Higher values may be possible, especially for bench-scale STRs. References were chosen that either measured kLa directly or offered a comprehensive review. Production scale systems may be more likely to offer the kLa range reported by Junker (2004) for large pilot plant STRs, with very high kLa’s only available in exceptional circumstances (Charles and Wilson, 2002).