Apparatus and method for diffused aeration
US7398963B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Jun 21, 2005 |
| Grant date | Jul 15, 2008 |
| Priority date | — |
| Expiry date | Sep 12, 2025 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01F2215/0422
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An apparatus for mixing gas and liquid is disclosed. The apparatus includes a draft tube having a gas inlet, a liquid inlet, a gas-liquid outlet, and an impeller rotatably mounted within the draft tube. The gas can be entrained into the liquid by rotation of an impeller having a low pitch ratio, such as less than 1:1. The impeller can have a diameter than is greater than the axial length of the impeller and includes at least one blade extending at least 30° around an axis of rotation of the impeller. Liquid turning vanes can also be positioned external to the draft tube to rotate liquid entering the draft tube in a direction opposite the direction of rotation of the impeller. The impeller can be constructed to create a reduced pressure zone, which directs gas axially downward within the draft tube upon rotation of the impeller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.