Patent · US Expired

Multiple screen filter and method

US5114595A · kind A · utility

13Cited by
11References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 19, 1991
Grant dateMay 19, 1992
Priority date
Expiry dateFeb 19, 2011

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D24/4631
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method and apparatus for filtering a fluid through a particulate filter medium and for periodically scrubbing the particulate filter medium of accumulated contaminating material. During the filtration cycle, the particulate filter medium is retained with a filtration vessel by a bottom screen. During the scrubbing cycle, the particulate filter medium is retained within the filtration vessel by the bottom screen and a top screen. The combined surface area of the bottom screen and the top screen is substantially greater than the surface area of the bottom screen alone. During the scrubbing cycle, the particulate filter medium is fluidized with a scrubbing fluid and violently circulated to remove accumulated contaminating material from the filter medium, thereby suspending the contaminating material in the fluidized mixture. Meanwhile, the level of suspended contaminating material in the fluidized mixture is diluted by circulating a scrubbing fluid through the fluidized filter medium so that the contaminating material is removed through both the bottom screen and the top screen but the particulate filter medium is retained within the filtration vessel by the bottom screen and the to…

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