Locally backwashing portions of filter media allows a simple and effective design of intake and pretreatment units, as well as their integration. An enclosure is used to limit portions of filter media and backwash them locally by suction, utilizing filtered water from adjacent filter media as the back wash water. Wastewater is produced at small amounts that allows efficient sludge treatment. This design enables water pretreatment at the intake unit, simplifying overall plant design and preventing damage to organisms living outside the intake unit.

A filtration apparatus whose interior is divided into a filtrate zone and a filtering zone. The filtering zone is adapted to receive a stream of raw-water and a lower portion of its volume is filled with filtering grains, and the filtrate zone is adapted to receive a filtrate obtained from passage of said stream of raw-water via the filtering grains and a perforated member. The apparatus further includes a pressure reducing device in fluid communication with the lower portion of the filtering zone and with an upper portion thereof. The pressure reducing device is adapted to receive a stream of water and responsively to continuously remove filtering grains from said filtering zone and separate filtration residues therefrom by the reduction of pressure conditions thereinside, and direct a stream comprising the stream of water and the separated filtering grains and filtration residues to the upper portion of said filtering zone.

Bio-filter unit (1) intended for a fish farming system, said bio-filter unit (1) comprising a container (2) with a filter media (3) and an inner architecture, said inner architecture comprising at least one vertical tube (5) having an open input end (6) and an open output end (7), wherein the bio-filter unit (1) is connected to a pump (8) enabling pumping liquid and filter media (3) from a bottom (9) of the container (2) against a top (10) of the container (2) through said at least one vertical tube (5), wherein an upper plate (15) is arranged inclined downwards from and around the open output end (7) of the at least one vertical tube (5) and ends at a distance from a wall (13) of the container, wherein the upper plate (15) Is perforated and wherein a regeneration water outflow (16) is arranged under the upper plate (15).

An upflow continuous backwash deep bed sand filter (UCBF) having a recycle line for returning carbonaceous denitrifying bacteria attached to biomass to the influent of the UCBF. The recycle line returns the biomass to the treatment process at a location upstream of the upflow continuous backwash filter. Further, a liquid level control unit is provided that reduces fluctuations and significant drop in the liquid level upstream of the upflow continuous backwash filter, thereby avoiding or minimizing flow turbulences, air induction, and undesirable wastewater aeration resulting in the need to dose excessive carbon source to remove dissolved oxygen in the aerated wastewater.

The present technology relates to control systems for use with fluid treatment systems. In one embodiment, for example, a fluid treatment system includes a vessel configured to receive a fluid having one or more constituents and to separate one or more constituents from the fluid. The system can also include a tube extending along at least a portion of the vessel and a sensor. The tube can be in fluid communication with a pressurized air source, and the sensor can be configured to obtain a measurement of an operating parameter. The system can also include a controller in communication with the sensor and pressurized air source. The controller can execute one or more algorithms to determine a filter parameter based on the measurement of the operating parameter, compare the filter parameter to a threshold, and, based on the comparison, activate or deactivate the pressurized air source.

A filtration apparatus includes a filtration tank; a layer of filtration media that filters supplied raw water by passing the raw water therethrough within the interior of the filtration tank; and a screw cleansing mechanism having a cylindrical outer cylinder which is provided within the filtration tank in a vertical orientation, a spiral shaped screw which is provided such that the long axis thereof extends in the longitudinal direction of the outer cylinder, and a screw driving member for rotating the screw, that scrubs and cleans filtration media by rotating the screw. The screw is in the shape of a coil spring.

Bio-filter unit (1) intended for a fish farming system, said bio-filter unit (1) comprising a container (2) with a filter media (3) and an inner architecture, said inner architecture comprising at least one vertical tube (5) having an open input end (6) and an open output end (7), wherein the bio-filter unit (1) is connected to a pump (8) enabling pumping liquid and filter media (3) from a bottom (9) of the container (2) against a top (10) of the container (2) through said at least one vertical tube (5), wherein an upper plate (15) is arranged inclined downwards from and around the open output end (7) of the at least one vertical tube (5) and ends at a distance from a wall (13) of the container, wherein the upper plate (15) Is perforated and wherein a regeneration water outflow (16) is arranged under the upper plate (15).

Provided is a process comprising receiving overflow of wastewater influent from a clarifier basin in a clarifier effluent collection trough; receiving inflow of wastewater influent from the clarifier effluent collection trough in a filter influent flow inlet distribution channel; maintaining substantially constant liquid level in the filter influent inlet distribution channel; applying hydrostatic pressure to push wastewater influent from the filter influent flow inlet distribution channel into an upflow backwash filter contusing denitrifying biomass or deammonification biomass; backwashing the backwash filter with a gas lift backwash flow; returning filter reject backwash wastewater from rejection compartment of the filter through denitrifying bacteria or deammonification biomass recycle return line to a location upstream of the filter; and recycling denitrifying bacteria or deammonification biomass from denitrifying bacteria or deammonification biomass recycle return line to at least one of the clarifier effluent collection trough, filter influent flocculation tank, or filter influent flow distribution channel.

Locally backwashing portions of filter media allows a simple and effective design of intake and pretreatment units, as well as their integration. An enclosure is used to limit portions of filter media and backwash them locally by suction, utilizing filtered water from adjacent filter media as the back wash water. Wastewater is produced at small amounts that allows efficient sludge treatment. This design enables water pretreatment at the intake unit, simplifying overall plant design and preventing damage to organisms living outside the intake unit.

A filtration apparatus includes a filtration tank; a layer of filtration media that filters supplied raw water by passing the raw water therethrough within the interior of the filtration tank; and a screw cleansing mechanism having a cylindrical outer cylinder which is provided within the filtration tank in a vertical orientation, a spiral shaped screw which is provided such that the long axis thereof extends in the longitudinal direction of the outer cylinder, and a screw driving member for rotating the screw, that scrubs and cleans filtration media by rotating the screw. The screw is in the shape of a coil spring.