Filter backwashing system using moveable member responsive to closing of filter outlet
OwnerJohn Reipur, Hans Olseninventors
Life of this patent
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Abstract
A method and apparatus for filtering a fluid flowing from a fluid supply duct in a first direction through a filtering medium in which separate solid particles or concentrate are released from the filtering medium by a back-flush. The method and apparatus has a moving means, such as a diaphragm, which receives the pressure of the fluid at both the inlet and outlet of the filter. In response to a changing pressure, such as by opening of an outlet valve, the moving means operates, e.g., the diaphragm changes its position, and operates to send a supply of the fluid through the filter medium in a second direction which is opposite to the normal first direction of fluid flow.
Claims23
A method of filtering a fluid flowing from a fluid supply duct in a first direction through a filtering medium into a fluid discharge duct, said method comprising the steps of:
- providing a member which is movable as a result of fluid pressure in both the fluid supply duct and the fluid discharge duct,
- selectively starting and stopping the fluid flow through the filtering medium by opening and closing the fluid discharge duct, and
- creating from said member a back-flush movement of the fluid in relation to the filtering medium in a second direction opposite to said first direction as a result of a change in fluid pressure acting on such member caused by at least one of the opening and closing of the fluid discharge duct.
A filtering apparatus for filtering a fluid comprising
- a filtering chamber having filter, fluid containing, inlet and outlet spaces,
- a fluid-penetrable filtering medium arranged within the filtering chamber so as to separate the fluid inlet and outlet spaces,
- means defining fluid inlet and outlet openings communicating with the filter inlet and outlet spaces to direct fluid to be filtered in a first direction from the inlet opening through the filtering medium to the outlet opening the outlet opening being selectively openable and closeable, and
- moving means responsive to the pressure of both the fluid int he inlet opening and the fluid in the outlet opening and responsive to a change in the fluid pressures caused by at least one of selectively opening and closing of the fluid outlet opening for moving fluid adjacent to the filter medium in relation to the filtering medium in a second direction opposite to said first direction to back-flush the filtering medium.
A method of filtering a fluid flowing from a fluid supply duct in a first direction through a filtering medium and into a fluid discharge duct, said method comprising:
- selectively starting and stopping the fluid flow through the filtering medium by opening and closing the fluid discharge duct, and
- causing a change in relative pressures between the fluid supply duct and a filter chamber in which the filtering medium is arranged by means of a movable, substantially fluid impervious chamber wall part, the wall part responding to a change in the fluid pressures caused by at least one of the opening and closing of the fluid discharge duct to create a back-flush movement of the fluid in relation to the filtering medium in a second direction opposite to said first direction.
A method of filtering a fluid flowing from a fluid supply duct in a first direction through a filtering medium into a fluid discharge duct, said method comprising:
- selectively starting and stopping the fluid flow through the filtering medium by opening and closing the fluid discharge duct, and
- moving the filtering medium in said first direction in relation tot he flush adjacent thereto when the fluid discharge duct is opened and creating a back fluid movement of the fluid in relation to the filtering medium in a second direction opposite to said first direction by a change in pressure conditions across a movable member caused by at least one of the opening and closing of the fluid discharge duct.
Dependencies are inferred from the claim text.