Patent ID: 7108250

Claim:
An apparatus for creating microbubbles of gas in a liquid, comprising: a containment vessel adapted to be positioned vertically and adapted to contain a volume of gas in an upper portion thereof under a second pressure exceeding ambient by at least 10 psi; elongate, hollow pipe means for providing said liquid to an interior of said vessel, having a longitudinal axis and of uniform wall thickness and having an interior cross-sectional area A i , said pipe means situate in said containment vessel and proximate said upper portion of said containment vessel and extending substantially vertically downwardly within said vessel, adapted for supplying a liquid under a first pressure greater than said second pressure to an interior of said vessel, said pipe means comprising a substantially rectangular pipe member of substantially rectangular exterior and interior dimensions, having a major exterior side length D 1 and a minor exterior side length D 2 and a major interior side length D 3 and a minor interior side length D 4 further having plug means situate at a distal end thereof for preventing egress of liquid vertically downward from said distal end; at least two apertures situate in said rectangular pipe member and disposed substantially perpendicular to a longitudinal axis of said pipe means extending from an interior of said pipe means to an exterior of said pipe means, each adapted to direct said liquid substantially horizontally outwardly from said pipe means, of combined cross-sectional exit area A c ; and said exit area A c of said apertures defined as a function of widths D 1 , D 2 , D 3 , and D 4 and said cross-sectional area A i of said pipe means, wherein A c is no greater than: A i ×[D 3 +D 4 ]/[D 1 +D 2 ].