×

Sewage treatment system

  • US 4,021,347 A
  • Filed: 01/09/1976
  • Issued: 05/03/1977
  • Est. Priority Date: 01/09/1976
  • Status: Expired due to Term
First Claim
Patent Images

1. A sewage treatment system comprising in combination:

  • (a) an enclosed, horizontally elongated tank of substantially uniform cross section between two end walls having an inlet opening in one end wall and an outlet opening in the opposite end wall;

    (b) an internal wall extending across the interior of said tank from the bottom thereof to an upper edge slightly below the level of the lowest edge of said inlet opening, dividing said tank into first and second compartments;

    (c) a first filter screen extending partially across the interior of said tank on the side of said internal wall nearest said opposite end wall;

    (d) a second filter screen arranged in substantially parallel, spaced relation to said first screen on the side thereof nearest said opposite end wall;

    (e) both of said filter screens having upper edges higher than the level of the lowest edge of said outlet opening, lower edges substantially higher than the bottom of said tank and lower than said outlet opening and coplanar side edges;

    (f) a pair of solid side walls extending from said opposite end wall to the side edges of both of said first and second screens, and a bottom wall extending from said opposite end wall only to the lower edge of said second screen whereby said side and bottom walls, said second screen and said opposite end wall define a third compartment;

    (g) said side walls having openings in the portions thereof between the side edges of said first and second screens, the area of said openings being sufficiently small that normal flow is essentially longitudinal, through said first screen, and sufficiently large to permit essentially unobstructed lateral flow to the space between said first and second screens in the event of blockage of said first screen; and

    (h) means within said first compartment for aerating liquid contents thereof, whereby sewage flowing through said tank from said inlet to said outlet openings is aerated in said first compartment, partially purified by gravity settling of a portion of the solids in said second compartment, and further purified by filtration through said screens in passing from said second to said third compartment.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×