GAS SPARGER FOR AN IMMERSED MEMBRANE

• US 20110049047A1
• Filed: 09/03/2009
• Published: 03/03/2011
• Est. Priority Date: 09/03/2009
• Status: Active Grant

• Current Assignee: BL Technologies Inc. (Ashland Global Holdings, Inc.)
• Original Assignee: General Electric Company
• Inventors: Hong, Youngseck, Bayly, Reid, Cumin, Jeff, Behmann, Henry
• Granted Patent: US 9,358,505 B2
• Time in Patent Office: Days
• US Class Current: 210/636
• CPC Class Codes: B01D 2313/26 Specific gas distributors or gas intakes
• CPC Class Codes: B01D 2315/06 Submerged-type; Immersion type
• CPC Class Codes: B01D 2321/185 Aeration
• CPC Class Codes: B01D 2321/26 By suction
• CPC Class Codes: B01D 61/12 Controlling or regulating
• CPC Class Codes: B01D 61/18 Apparatus therefor
• CPC Class Codes: B01D 61/22 Controlling or regulating
• CPC Class Codes: B01D 65/00 Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
• CPC Class Codes: B01D 65/02 Membrane cleaning or sterilisation ; Membrane regeneration
• CPC Class Codes: B01D 65/08 Prevention of membrane fouling or of concentration polarisation
• CPC Class Codes: B01F 23/2312 Diffusers
• CPC Class Codes: B01F 23/23123 consisting of rigid porous or perforated material
• CPC Class Codes: B01F 23/231242 in the form of slits or cut-out openings
• CPC Class Codes: B01F 23/231244 Dissolving, hollow fiber membranes
• CPC Class Codes: B01F 23/231263 having dome-, cap- or inversed cone-shape
• CPC Class Codes: B01F 23/231265 being tubes, tubular elements, cylindrical elements or set of tubes
• CPC Class Codes: Y02W 10/10 Biological treatment of water, waste water, or sewage

Abstract

A gas sparger produces an intermittent flow of bubbles even if provided with a continuous gas flow. The sparger has a housing to collect a pocket of gas and a conduit to release some of the gas from the pocket when the pocket reaches a sufficient size. Optionally, a cover over an outlet from the conduit may break up or distribute the released gas. A large sparger for use with a commercial membrane module can comprise a plurality of smaller units.

Claims

1. An apparatus for providing gas bubbles in a liquid comprising,

a) a housing defining a chamber and having an opening below the chamber allowing communication between the inside of the chamber and the outside of the chamber;

and,

b) a conduit, the conduit having a first opening inside of the chamber and a second opening in communication with the outside of the chamber, and defining a closed channel having a portion that extends downwards to a low point of the conduit in a direction from the first opening to the second opening,

wherein,

c) the chamber is adapted to hold a pocket of the gas above an interface between the gas pocket and the liquid, the interface having a variable elevation ranging from at least a lower boundary of the first opening in the conduit to an upper boundary of the low point of the conduit.

2. The apparatus of claim 1 wherein the second opening of the conduit is above the low point of the conduit.

3. The apparatus of claim 2 wherein the second opening of the conduit is at or above the first opening.

4. The apparatus of claim 1 further comprising a gas supply pipe having an outlet to discharge gas into the chamber above the first opening of the conduit.

5. The apparatus of claim 1 further comprising a gas supply pipe having an outlet to discharge gas into the chamber below the upper bound of the low point of the conduit.

6. The apparatus of claim 1 further comprising a cover with a plurality of holes over the second opening of the conduit.

7. The apparatus of claim 1 wherein the second opening has an area of 1-10 square cm.

8. The apparatus of claim 1 wherein the cross-sectional area of the second opening of the conduit is less than the horizontal cross-sectional area of the associated chamber by a factor of at least 10.

9. An assembly comprising an immersed membrane module, the immersed membrane module having a lower potting head, and one or more apparatus according claim 1 located below, beside or in combination with the lower potting head.

10. The assembly of claim 9 having a plurality of apparatus according to claim 1 located below, beside or in combination with the lower potting head.

11. The assembly of claim 10 having a gas supply pipe having or connected to an outlet for discharging gas into each of the chambers.

12. A sparger for an immersed membrane module comprising,

a) an elongated housing having walls extending downwards from an upper part of the housing, the housing defining a plenum with an open bottom;

b) a plurality of conduits generally located within and spaced along the length of the housing, each of the conduits having a first opening in communication with the interior of the housing, a second opening through an upper part of the housing and a low point between the first and second openings.

13. The gas sparger of claim 12 further comprising a cover with holes over the second openings of the tubes.

14. The gas sparger of claim 12 having dividers within the housing between the tubes.

15. The gas sparger of claim 13 having dividers within the cover between the second openings.

16. The gas sparger of claim 12 further comprising a gas distribution pipe along the length of the housing for discharging gas into the chambers.

17. A process for gas sparging a membrane module immersed in a liquid, the process comprising the steps of,

a) immersing a sparger in the liquid, the sparger having a conduit with an outlet from the sparger and an inlet, the inlet in communication with a chamber defined by the sparger and adapted to hold a pocket of gas in the liquid, the conduit having a low point between the inlet and outlet;

and,

b) feeding gas into the sparger at a rate sufficient to cause bubbles to emerge from the outlet at least once every 30 seconds.

18. The process of claim 17 further comprises a step of diffusing or distributing the bubbles after they emerge from the outlet.

19. The process of claim 17 further comprising a step of locating the sparger below, beside or in combination with the module.

20. The process of claim 17 wherein gas is fed into the sparger at a rate such that bubbles emerge from the outlet in a burst once every 2 to 20 seconds.