Patent · US Expired

Air drying apparatus and method

US6719825B2 · kind B2 · utility

17Cited by
34References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 7, 2002
Grant dateApr 13, 2004
Priority date
Expiry dateMay 7, 2022

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D53/268
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Apparatus and methods are disclosed for using membranes to reduce the relative humidity of a compressed air stream. Air dryers employing membranes consist of a permeable membrane capable of blocking the passage of nitrogen and oxygen molecules, but allowing water vapor molecules to pass through. A membrane filter may be adapted to receive process flow of contaminated air. A sweep chamber may be positioned adjacent to filtration media to pass a portion of dried air back into contact with a portion of the membrane. A flow metering device may be positioned downstream from the membrane filter to adjust a portion of the air process flow as sweep air. The amount of process flow air diverted as sweep air may be proportional to the pressure and flow of the process flow. In some applications, an optional minimum pressure valve may be employed downstream of the sweep chamber to maintain a minimum threshold pressure of process air flow.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.