Patent · US Expired

Backwash apparatus for multi element filter unit

US4642188A · kind A · utility

46Cited by
7References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 29, 1985
Grant dateFeb 10, 1987
Priority date
Expiry dateMay 29, 2005

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D2201/0469
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A multi-element filter unit includes backwash apparatus and comprises a filter casing with provision for alternative, oppositely directed process liquid and backwash liquid flows therethrough. A plurality of filter tubes are close spaced within the filter casing. A flange engages the filter tubes and divides the filter casing into first and second chambers. Apparatus for sequentially backwashing the filter tubes during a backwash interval removes collected solids from between the filter tubes by flow of backwash liquid from one filter tube outward toward the exterior of adjacent filter tubes. The backwash apparatus includes poppet units aligned with open ends of the filter tubes and selectively actuable to close the opposed ends of ones of the filter tubes while leaving another open to backwash flow thereinto, such that each filter tube is backwashed in sequence while the others are closed against backwasing liquid flow thereinto, and diffuser structure which apportions, lengthwise of the filter tube, the rate of backwash liquid flow radially out through the wall of each filter tube.

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