The present invention relates to a multistage fiber filtering apparatus capable of selectively filtering depending on turbidity of raw water, in which a first filtration mode where the raw water passes through a fiber ball medium, a second filtration mode where the raw water passes through a fiber yarn medium, or a third filtration mode where the raw water passes through both of the fiber yarn medium and the fiber ball medium may be selectively operated.

The present invention relates to a multistage fiber filtering apparatus capable of selectively filtering depending on turbidity of raw water, in which a first filtration mode where the raw water passes through a fiber ball medium, a second filtration mode where the raw water passes through a fiber yarn medium, or a third filtration mode where the raw water passes through both of the fiber yarn medium and the fiber ball medium may be selectively operated.

Embodiments of the present disclosure describe filter agitators, filtration units comprising the filter agitators, methods of using the filter agitators, and the like. In certain embodiments, the filter agitators comprise a plurality of first fins extending outwardly from a central vertical axis and arranged in a plane oriented substantially perpendicular to the central vertical axis, wherein the plurality of first fins is configured to promote laminar flow of a fluid flowing in a first direction and induce turbulent flow of a fluid flowing in a second direction; and optionally a plurality of second fins positioned above the plurality of first fins and extending outwardly from the central vertical axis, wherein the plurality of second fins is configured to induce or further induce turbulent flow.

Embodiments of the present disclosure describe filter agitators, filtration units comprising the filter agitators, methods of using the filter agitators, and the like. In certain embodiments, the filter agitators comprise a plurality of first fins extending outwardly from a central vertical axis and arranged in a plane oriented substantially perpendicular to the central vertical axis, wherein the plurality of first fins is configured to promote laminar flow of a fluid flowing in a first direction and induce turbulent flow of a fluid flowing in a second direction; and optionally a plurality of second fins positioned above the plurality of first fins and extending outwardly from the central vertical axis, wherein the plurality of second fins is configured to induce or further induce turbulent flow.

The present invention relates to a multistage fiber filtering apparatus capable of selectively filtering depending on turbidity of raw water, in which a first filtration mode where the raw water passes through a fiber ball medium, a second filtration mode where the raw water passes through a fiber yarn medium, or a third filtration mode where the raw water passes through both of the fiber yarn medium and the fiber ball medium may be selectively operated.

The present invention relates to a multistage fiber filtering apparatus capable of selectively filtering depending on turbidity of raw water, in which a first filtration mode where the raw water passes through a fiber ball medium, a second filtration mode where the raw water passes through a fiber yarn medium, or a third filtration mode where the raw water passes through both of the fiber yarn medium and the fiber ball medium may be selectively operated.

A method and an apparatus for treating a liquid containing impurities may include a filtering chamber configured to permit granular media to interact with liquid containing impurities, thereby removing impurities from the liquid to produce filtrate; a filtrate section for receiving the filtrate; a gas supplying system for delivering gas to the granular media in the filtering chamber for transport of a portion of the granular media to a granular media washer; a reject section in fluid communication with the granular media washer for receiving a reject mixture comprising liquid and impurities from the granular media washer; and a control unit that is configured to determine whether the portion of the granular media is being transported properly based on an amount of reject mixture in the reject section.

Systems and methods for treating wastewater are disclosed. Zero valent iron media may be used in a moving packed bed reactor. A media recovery system may return media to the reactor.

A system and method for recycling gas in a backwash process is provided. The backwash process removes contaminants from a bed of filtration media. The method includes generating a mixed liquid-gas stream from the backwash process, withdrawing the mixed liquid-gas stream from the backwash process, separating the mixed liquid-gas stream into a liquid and a gas, and recycling at least a portion of the separated gas to the backwash process.