Gas-liquid venturi mixer
AssigneeRhone-Poulenc Inc.
InventorBlair Howard Hills
Life of this patent
Estimating the term…
Abstract
An apparatus and method are provided for mixing gas and liquid. An impeller is rotatably mounted inside a draft tube having a constricted section. Rotation of the impeller draws liquid down through the constricted portion of the draft tube. A gas delivery system introduces gas under the surface of the liquid downstream from the constricted portion of the draft tube to entrain the gas in the liquid by a venturi effect. The impeller creates a turbulent gas-liquid mixing zone and also projects liquid radially into the gas as it enters the draft tube. The gas-liquid venturi mixer is particularly suitable for treating industrial and municipal waste water, as well as various other liquids. Gases such as air, oxygen, hydrogen, and the like are efficiently dissolved in such liquids during operation of the gas-liquid venturi mixer.
Claims39
An apparatus for mixing gas and liquid comprising:
- a draft tube having a liquid inlet end, a liquid outlet end and a constricted portion between the liquid inlet end and the liquid outlet end, wherein the constricted portion projects within the confines of the draft tube;
- at least one impeller rotatably mounted at least partially inside the draft tube;
- and
- a gas delivery system having at least one gas outlet end downstream from the constricted portion in flow communication with the liquid inlet end of the draft tube adjacent a periphery of the draft tube.
An apparatus for mixing gas and liquid comprising:
- a draft tube;
- impeller means at least partially inside the draft tube for drawing liquid through the draft tube;
- gas delivery means for delivering gas to the draft tube under the surface of the liquid;
- and
- venturi means for entraining the gas in the liquid as the liquid is drawn through the draft tube by the impeller means and after the liquid passes a constricted portion of the draft tube, wherein the constricted portion projects within the confines of the draft tube.
An apparatus for mixing gas and liquid comprising:
- a draft tube;
- a constricted portion of the draft tube, wherein the constricted portion projects within the confines of the draft tube;
- gas delivery means for delivering gas to the draft tube;
- and
- impeller means at least partially inside the draft tube for drawing liquid through the draft tube, wherein a zone of low gas pressure is created behind a swept volume of the impeller, and wherein at least a portion of the gas is contacted with the liquid as the gas enters the draft tube adjacent to the low gas pressure zone.
A method of mixing gas and liquid, the method comprising:
- providing a draft tube;
- providing a constricted portion of the draft tube, wherein the constricted portion projects within the confines of the draft tube;
- mounting an impeller at least partially inside the draft tube;
- providing a supply of gas to the draft tube;
- submerging the draft tube in a liquid;
- and
- rotating the impeller to draw the liquid through the draft tube, creating a zone of low gas pressure behind a swept volume of the impeller, and contacting at least a portion of the gas with the liquid as the gas enters the draft tube adjacent to the low gas pressure zone.
Dependencies are inferred from the claim text.