Disclosed is a process for treating wastewaters including at least one step of aerobic biological treatment of the wastewaters in a biological reactor (3), as well as a step of ozonation during which ozone is injected into one or more circuits (1, 6) arranged to transport a respective fluid into the biological reactor (3). Also disclosed is a device relating thereto.

A tank suited for use as a septic tank or for otherwise holding or treating water has a top hatchway large enough to enable an adult person to enter the tank. The hatchway is closed by a lid which has a port with a removable cover, where the port that is large enough to enable through-passage of a suction line for cleaning the tank, but small enough to prevent a child from entering the tank. Preferably the port area is less than 6 percent of the effective area of the lid and the centerline of the port lies at a location which is between 20 to 80 percent of the radius of the lid.

An apparatus for converting the septic tank into an aerobic treatment system has a clarifier with a collapsible wall which allows the clarifier to fold in order to pass through the opening of the septic tank and to unfold upon entry into the septic tank, an aerator having a size suitable for passing through the opening of the septic tank in position between the wall of the clarifier and a wall of the septic tank, and an air pump connected to the aerator so as to pass air to the aerator. The clarifier has an opening at a bottom thereof having a diameter no greater than a diameter of the top of the clarifier. The effluent outlet pipe is received in an aperture formed in a wall of the clarifier.

A reactor for treating water, the reactor comprising a buoyant structure for supporting at least one cell for suspension in a body of water in use, wherein each cell is removeably attachable to the buoyant structure and is arranged to house biomedia. A water treatment system comprising the reactor in a body of water. A method of treating water comprising passing water to be treated through the reactor in a body of water.

Described herein are attached growth reactor systems which increase nitrifying bacteria biomass through a variety of means during warm weather. As a consequence, the attached growth reactor system contains sufficient nitrifying bacteria biomass to remove ammonia from wastewater in cold to moderate climates. In one example, there are two attached growth reactors into which wastewater is distributed discontinuously. Specifically, wastewater is transferred to the first attached growth reactor for a first period of time and then is transferred to the second attached growth reactor for a second period of time during warm weather which effectively doubles the nitrifying bacteria biomass in the system. During cold weather, approximately half of the wastewater is applied to each reactor simultaneously.

Aerobic wastewater treatment systems may include a treatment tank having a tank interior. An aeration chamber may be provided in the tank interior. A wastewater inlet conduit may be disposed in fluid communication with the aeration chamber. An air inlet conduit may be disposed in fluid communication with the aeration chamber. A diffuser may be provided in the aeration chamber. The diffuser may be disposed in pneumatic communication with the air inlet conduit. A clarifier in the tank interior may include a vertical outside clarifier wall portion. An inside clarifier wall portion may be disposed at an acute angle to the outside clarifier wall portion. A clarifier interior may be formed by and between the outside clarifier wall portion and the inside clarifier wall portion. A clarifier inlet may establish fluid communication between the aeration chamber and the clarifier interior. An effluent outlet conduit may be disposed in fluid communication with the clarifier interior. Aerobic wastewater treatment system fabrication methods are also disclosed.

Disclosed is an apparatus for treating wastewater that includes a tank having a wall, defining an inner surface, and a floor; a clarifier having an outer surface selectably fixed relative to said tank; and a diffuser; wherein the inner surface, the outer surface and the diffuser are configured to compel wastewater in the tank to define a flow along a direction up the outer surface and down the inner surface. A method of treating wastewater also is disclosed.

A water treatment system comprising a first reactor and a second reactor arranged to be placed in series in a body of water, the first and/or second reactor comprising at least one cell for housing biomedia. A mid-settling zone is provided between the first and second reactors for separating solids in the water. A method of treating water, the method comprising passing water to be treated through a first reactor and then a second reactor arranged in series in a body of water, the first and/or second reactors comprising at least one cell for housing biomedia, wherein the water is passed through a mid-settling zone between the first and second reactors before passing through the second reactor.

Described herein are attached growth reactor systems which increase nitrifying bacteria biomass through a variety of means during warm weather. As a consequence, the attached growth reactor system contains sufficient nitrifying bacteria biomass to remove ammonia from wastewater in cold to moderate climates. In one example, there are two attached growth reactors into which wastewater is distributed discontinuously. Specifically, wastewater is transferred to the first attached growth reactor for a first period of time and then is transferred to the second attached growth reactor for a second period of time during warm weather which effectively doubles the nitrifying bacteria biomass in the system. During cold weather, approximately half of the wastewater is applied to each reactor simultaneously.

A round meander septic tank includes an elongate baffle that divides the interior space of the tank into two semicircular chambers. Untreated wastewater is introduced to the first chamber through an inlet located near the first end of the baffle. The wastewater flows through the first chamber to a portal at the second end of the baffle and passes through the portal into the second chamber. A wastewater outlet from the tank is located in the second chamber near the first end of the baffle. Wastewater passing through the portal flows through the second chamber to the outlet and out of the tank. The baffle and the shape of the septic tank increase the distance that the wastewater must flow from the inlet to the outlet as compared to a rectangular meander tank with a single baffle.