Abstract: Apparatus for treating water has a generally rectangular container for containing the water, the container having a clarification zone and a settling zone. An entry conduit extends along the container and receives water from a water inlet. Water outlet ports are distributed along the length of the conduit for directing water from the conduit into the settling zone. A water exit trough spaced across the container from the entry conduit and extending along the container receives clarified water flowing from the settling zone through the clarification zone. The top of the settling zone is open to allow access down through the settling zone to a sludge collection zone in the bottom of the container.

Abstract: Apparatus for treating water has a container having a clarification zone, a water entry arrangement for flowing water into the clarification zone, and skimmer elements mounted to the container for partial immersion in the water in the clarification zone. Each skimmer element has a transfer channel for transferring a flow of clarified water from a layer of the water to a predetermined depth in the clarification zone and to direct the received clarified water to a water exit arrangement. A height adjustment mechanism is used for differentially adjusting the heights of the skimmer elements and their transfer channels relative to the container so as to compensate for the clarifier being installed on sloping ground.

Abstract: A method and apparatus for cleaning a membrane bioreactor having a stack of generally vertically oriented membrane filter plates mounted in a filtration chamber containing wastewater. In a first cleaning phase, air is supplied to a first discharge zone under the stack to discharge gas bubbles into the wastewater at the bottom of the stack so that the gas bubbles rise upwardly through passages between the filter plates to scour surfaces of the membranes bounding the passages. In a second cleaning phase, gas is supplied to a second discharge zone at the bottom of the stack and surrounding it to cause air lift induced circulation of the wastewater up around the sides of the stack and downwardly through the passages between the filter plates to eject accumulated fibrous material from the passages and to scour surfaces of the membranes bounding the passages.