One or more aerators move below an area of an assembly of immersed filtering membranes to be aerated. The movement can take various forms including the sweep of a pendulum. Positions in the assembly of membranes may be alternately aerated for a period of time and then not aerated for a period of time.

Moving aerator for immersed membranes

The invention generally provides an apparatus that aerates the aquatic environment and agitates the bottom of the aquatic environment. One aspect of the invention provides a variable buoyancy aerator which cycles between an agitation mode and an aeration mode. Another aspect of the invention provides a system for maintaining an aqua-culture environment including one or more variable buoyancy aerators, a power source connected to supply power to activate the aerators and a controller connected to the power source to regulate activation of each aerator. The invention also provides a method for maintaining an aqua-culture environment including positioning one or more variable buoyancy aerators within the aqua-culture environment and regulating activation of each aerator to provide aeration, bottom agitation and controlled circulation to the aquatic environment.

Apparatus for aeration and bottom agitation for aqua-culture systems

A diffuser assembly with a buoyancy vessel and a chamber for buoyantly raising the diffuser assembly for maintenance work. The diffuser assembly has a support structure, diffusers connected to the frame, and a buoyancy vessel positioned on the frame, capable of alternating between a state of buoyancy or ballast.

Diffuser assembly with buoyancy vessel

A counterbalanced, dual submarine-type liquid mixer provides a pair of counterbalanced mixing devices that move at opposing ends of a balance bar (40) suspended above the surface of a liquid (10) to be mixed. The bar (40) is able to pivot so as to vertically move its ends (44, 46) alternately between a raised and a lowered position in such a manner that when one of the mixing devices is in a raised position in the liquid (10), the other of the mixing devices is in a lowered position and each of the two mixing devices tends to counterbalance the other.

Counterbalanced dual submarine-type liquid mixer pairs

The invention relates to a method for stirring and/or aerating fluids, particularly sewage, having the following cyclically repeated steps: aerating the fluid by means of an immersed aerator for a predetermined first period of time (t1) using an aeration device (1) disposed on a carrier (3, 43) designed as a floodable hollow body (2, 42), the hollow body (2, 42) being flooded and air being brought into the fluid by the aeration device, whereby the potential for nitrification is created in the fluid; stirring the fluid by means of the immersed aerator for a predetermined second period of time (t2), the air infeed by the aeration device (1) being throttled or turned off, and the previously flooded hollow body being evacuated in order to fill the hollow body (2, 42) with gas or air, the immersed aerator assuming the function of a mixing device in which fluid rises upward, thus mixing the fluid, wherein the potential for denitrification is created in the fluid; and an immersed aerator.

Method for stirring and/or aerating fluids, particularly sewage, particularly using a floodable aerator

In the submerged diffuser arrangement described in the specification, a plurality of submerged air diffuser arrangements are disposed adjacent to the bottom of in a body of wastewater to be aerated and connected an air supply pipe extending along the surface of the wastewater. Air is supplied from the air supply pipe through downcomers leading to the diffuser arrangements. The diffusers may be suspended from the air pipe above the bottom or they may rest on the bottom. In order to raise the diffuser arrangements to the surface of the wastewater for servicing, inflatable buoyant members are affixed to each diffuser arrangement or to the lower ends of the associated downcomers. The inflatable buoyant members are connected through tubing to valves from which air may be supplied under pressure, either from the air supply pipe or form a portable air compressor or a compressed air container or through an air pressure line leading from a remote air supply located on the shore of the basin.

Daniel E. Loy

Papers

Submerged diffuser lifting arrangement