The invention relates to a device for metering an additive into a fluid, containing a valve body, a fluid inlet, and a fluid outlet. A first channel system extends between the fluid inlet and the fluid outlet in the valve body, and a second channel system extends between the fluid inlet and the fluid outlet in the valve body such that in the operating state fluid can flow from the fluid inlet to the fluid outlet either through the first channel system or through the second channel system. The valve body contains a docking element which is configured for docking a cartridge for the additive. A switchover device is provided which can be switched if the cartridge is docked such that the second channel system is fluidically connected to the cartridge when the cartridge is connected to the docking element.

The invention relates to a method for removing a chemical substance from human excreta, such as faeces and urine, comprising the following steps of: providing a toilet for a person from whose excreta the chemical substance must be removed; releasably connecting a filtering device to the toilet, wherein the filtering device comprises at least one removable cartridge with a filter; transporting the excreta by means of a transport screw from the toilet toward the filter in the cartridge, wherein pressure is exerted on the excreta by means of a plunger; filtering the chemical substance out of the excreta in situ using the filtering device; periodically replacing the at least one cartridge; and processing the replaced cartridge. The invention also relates to a filtering device for application in this method, and a cartridge for use in such a filtering device.

The present invention relates to modification to permeate channels and permeate materials in a cross-flow filtration system to improve performance in counter current filtration having both retentate channels and permeate channels wherein a solution is pumped through one of the channels and drawn through a membrane to one of the other channels to assist in positive pressure driven filtration by using the osmotic pressure, concentration, or preferential solubility difference between the retentate and permeate flow streams thereby increasing or altering the flux through the membrane separating the flow streams.

A water filter cartridge is provided for gravity-feed water filtration applications, and includes a granular filter media made from a mixture of titanium dioxide particles interspersed with granular activated charcoal. The granular filter media is placed in a filter housing having an upper inlet opening and a lower outlet opening. A seal may be disposed around an outer periphery of the housing at its upper region, and may include a flange region that flexes upwardly upon insertion of the sidewall into a filter cartridge opening.

A sanitation device for cleaning a body of water in an immersion pool of a mikvah has a housing, a driving member and a bypass passageway. The housing includes an inlet, an outlet and internal liquid passages that communicate between the inlet and outlet. The driving member is arranged to urge flow of liquid through the internal liquid passages by exerting thrust upon liquid flowing through the driving member, wherein at least part of the liquid flowing through the liquid passages bypasses flowing through the driving member by flowing through the bypass passageway towards the device's outlet.

A filter medium of the present invention includes a porous carbon material having a value of a specific surface area by a nitrogen BET method of 1×10.sup.2 m.sup.2/g or more, a volume of fine pores by a BJH method of 0.3 cm.sup.3/g or more, and a particle size of 75 μm or more, alternatively, a porous carbon material having a value of a specific surface area by a nitrogen BET method of 1×10.sup.2 m.sup.2/g or more, a total of volumes of fine pores having a diameter of from 1×10.sup.−9 m to 5×10.sup.−7 m, obtained by a non-localized density functional theory method, of 1.0 cm.sup.3/g or more, and a particle size of 75 μm or more.

A filter assembly for filtering water in spas, swimming pools, hot tubs and whirlpools, having a first or outer filter element, a second or inner filter element removably installed within the outer filter element, a first coupling member associated with the outer filter element, a second coupling member associated with the inner filter element, the first and second coupling members engaging one another to connect the inner filter element with the outer filter element, and a releasable detent arrangement resisting disengagement of the first and second coupling members from one another. The outer filter element includes a filter medium for mechanically removing particulates from a fluid to be treated and the inner filter element includes a filter medium containing fluid purifying particles.

A water purifier structure includes a container assembly and a buffer unit mounted in the container assembly. The container assembly includes a housing and a cap unit. The housing has a first receiving section and a second receiving section. The second receiving section of the housing is provided with a retaining portion. The buffer unit is mounted in the second receiving section of the housing and includes a positioning ring secured in the retaining portion of the housing, and a cushioning member mounted in the positioning ring. The cushioning member is elastically movable in the positioning ring. When the cushioning member is compressed by a force, the cushioning member is contracted and elastically deformed toward the second receiving section of the housing, to form a buffering force.

A filter device for filtering water. The device includes a housing, for submersion in a water reservoir, that includes an intake aperture for intake of water from the reservoir and a return aperture for returning water to the reservoir. The housing extends along an axis. The device includes a pump, housed in the housing, arranged on the axis to direct fluid from the intake aperture to the return aperture. The device includes a filter arrangement, housed in the housing, arranged along the axis from the pump in a fluid path between the intake aperture and the return aperture.

A filter medium for removing contaminants from water includes a matrix including a plurality of fibers having an electrostatic charge such that the matrix is configured to remove contaminants from water by electrostatic attraction. The filter medium further includes a filler material including a ceramic substrate containing a mineral. The filler material is embedded in the matrix. When water flows through the filter medium, the mineral at least partially dissolves in the water such that a cavity is formed in the matrix in a location of the at least partially dissolved mineral.