Table 1. Overview of blower types for aeration of wastewater (USEPA, 2010)
Table 2. Typical efficiencies (USEPA, 2010)
| Blower Type | Nominal Blower Efficiency (%) | Nominal Turndown (% of rated flow) |
| Positive displacement (variable speed) | 40-65 | 50 |
| Multi-stage centrifugal (inlet throttled) | 50-70 | 60 |
| Multi-stage centrifugal (variable speed) | 60-70 | 50 |
| Single-stage centrifugal, integrally geared (with inlet guide vanes and variable diffuser vanes) | 70-80 | 45 |
| Single-stage centrifugal, gearless (high speed turbo) | 79-80 | 50 |
Note: values may vary depending on the application
© Seong Hoon Yoon