Patent · US Expired

Apparatus for supercritical cleaning

US5355901A · kind A · utility

64Cited by
23References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 27, 1992
Grant dateOct 18, 1994
Priority date
Expiry dateOct 27, 2012

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB08B7/0021
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An apparatus for precision cleaning with carbon dioxide includes a pressure vessel having a removable cleaning drum with a sanitized work zone, a separator for regenerating spent carbon dioxide, and pressure and temperature monitoring and control devices to maintain the carbon dioxide in a supercritical state while it is circulated in contact with a part to be cleaned. The sanitized work zone is defined by an impermeable drum body having removable entry and exit filters to ensure that circulating cleaning fluid does not redeposit contaminants on the parts. The separator includes distillation means. The pressure vessel and separator form part of an overall system, including a storage vessel for carbon dioxide, a pump, a preheater, a let-down valve in communication with the pressure vessel outlet, a condenser and a bypass. The carbon dioxide is maintained in liquid form in the storage vessel, raised above its critical temperature by the preheater, pumped into the pressure vessel to achieve critical pressure, circulated through the work zone for a predetermined period of time, and removed through the let-down valve. The separator regenerates the carbon dioxide and carbon dioxide gas i…

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