Integrated gas sparger for an immersed membrane
View Patent ↗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. The housing is integrated with the potting head of a module. The conduit passes through the potting head.
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 portion of the conduit 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;
d) the housing is integrated with a potting head of a membrane module;
e) the closed portion of the conduit extends upwards from the low point of the conduit and passes through the potting head;
f) the closed portion of the conduit extends continuously from the first opening to the second opening; and,
wherein the potting head is a block of hardened resin into which membranes of the membrane module are potted.
2. The apparatus of claim 1 wherein the second opening of the conduit is above the first opening.
3. The apparatus of claim 1 further comprising a gas supply conduit integrated with the potting head of the membrane module and having an outlet to discharge gas into the chamber wherein the closed portion of the conduit extends through the gas supply conduit.
4. 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 portion of the conduit 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;
d) the housing is integrated with a potting head of a membrane module; and,
e) the closed portion of the conduit extends upwards from the low point of the conduit and passes through the potting head,
further comprising a cap or diffuser above the potting head and over the second opening of the conduit,
wherein the potting head is a block of hardened resin into which membranes of the membrane module are potted.
5. The apparatus of claim 1 wherein the second opening has an area of 1-10 square cm.
6. 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.
7. The apparatus of claim 1 wherein the membrane module further comprises a permeate cavity below the potting head and the closed portion of the conduit extends through the permeate cavity.