The present invention provides a depth filter which contains fine particles and coarse particles, and which exhibits excellent filtration precision with respect to a high concentration fluid and/or a high viscosity fluid. This depth filter enables filtration for a long period of time, while maintaining a low filtration pressure.

The present invention is a depth filter which is obtained by winding a fiber sheet into a cylinder, and which comprises a pre-filtration layer and a microfiltration layer; the pre-filtration layer and the microfiltration layer are formed of a fiber sheet; the fiber sheet is composed of a nonwoven fabric or a web; the average fiber diameter of the fiber sheet continuously decreases from the pre-filtration layer toward the microfiltration layer; and the average weight per square meter of the fiber sheet continuously decreases from the pre-filtration layer toward the microfiltration layer.

A filtration system using lightweight fibrous media (LFM) that are pre-compressed either 1) manually; or 2) in-situ using hydraulic flow; and where the LFM are forced to separate and relax for cleaning either: 1) manually, 2) in-situ in their filter housing, or 3) in an auto-clean system using separate devices in order to enact a particularly aggressive cleaning process. A plurality of lightweight fibrous media balls are pre-compressed and used to form a single mass that can filter water as the media are compressed by pre-compression before installation, or by water flow pushing on a pre-compression plate during filtration thereby forming a single mass providing multitudes of tortuous paths through which water can flow and the media can capture small particulate matter.

A reverse osmosis prefilter system includes a recirculation chamber for accommodating one or more prefilter cartridges. The recirculation chamber is communicably interconnected to an inline water source and an RO filtration membrane. The recirculation chamber has a recirculation outlet and inlet which are communicably interconnected by an offline pump that recirculates prefiltered water repeatedly through the recirculation chamber and prefilter cartridges to remove particulates from the source water prior to delivery to the reverse osmosis filter membrane.

A gradient density filter element, and associated method, and an associated apparatus are provided. The gradient density filter element includes a gradient density filter media formed via compression during winding of a layer of filter media into a cylindrical roll.

A nutrient concentration and water recovery system includes a first suspended solids settling tank configured to receive a flow stream that includes a waste stream with a sludge stream. A first centrifugal pump is coupled to the first suspended solids settling tank. The first centrifugal pump having corrosion resistant wetted parts and variable speed drives to transfer or pressurize process flow streams. A first level transmitter coupled to the first centrifugal pump that provides output signals in response to a level of a process material within the first suspended solids settling tank. The first level transmitter is mounted in the first suspended solids settling tank. A first flow transmitter coupled to the first level transmitter is configured to measure a specific volume of material transferred out of the first suspended solids settling tank. A first pump is coupled to the first flow meter and configured to transfer a flush water that includes suspended solids and inorganics. A vibrating screen is coupled to the first pump. A process tank is coupled to the submersible pump. A sedimentation removal system and a removal device coupled to the sedimentation removal system are provided and configured to remove inorganizes out of a suspension.

An oil filtration unit having an inlet adapted to receive contaminated oil from the surroundings and to release the contaminated oil to an inner opening of the unit, and an outlet adapted to release filtered oil to the surroundings. The inner opening has therein an oil filter for filtering the contaminated oil. The oil filter has a filter inlet defined by an outer surface of the oil filter, an inner filter volume adapted to receive filtered oil, and a filter that provides fluid/liquid communication between the inner filter volume and the outlet of the unit in order to release filtered oil from the inner filter volume. The oil filter has a top and a bottom end surface, where the top end surface of the oil filter has an aperture for providing fluid/liquid communication between the inner opening of the unit and the inner filter volume.

To provide a filter capable of efficiently removing metal ions in a treatment liquid, and capable of easily obtaining a solution having an extremely low metal ion content. A depth filter includes a porous molded article. The porous molded article is a sintered material of mixed powder or a swollen material of the sintered material. The mixed powder contains dried gel powder and thermoplastic resin powder. The dried gel powder contains an ion exchange resin including a sulfonic acid group, and a nitrogen-containing chelating resin.

In a method and a system for purification of contaminated oil, the contaminated oil and a liquid separation aid are provided in a mixing tank and then mixed into a mixture. Thereafter, the mixture is filtered.

Depth filters with optimized head space are provided, as well as methods of optimizing the head space in depth filters, and methods of filtration with depth filters having optimized head space, including clarification of flocculated feed streams where pretreatment may include any of lowering cell culture pH, addition of polymers (uncharged or charged), or addition of salts to precipitate out solubilized impurities resulting in high insoluble biomass.

A reverse osmosis prefilter system includes a recirculation chamber for accommodating one or more prefilter cartridges. The recirculation chamber is communicably interconnected to an inline water source and an RO filtration membrane. The recirculation chamber has a recirculation outlet and inlet which are communicably interconnected by an offline pump that recirculates prefiltered water repeatedly through the recirculation chamber and prefilter cartridges to remove particulates from the source water prior to delivery to the reverse osmosis filter membrane.