Apparatus for filtering liquids
AssigneeIngenjorsfirman R. Frykhult AB
InventorRune Frykhult
Life of this patent
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Abstract
An apparatus for filtering liquids, especially for recovering fibers from white water, includes rotatable filter discs at least partially immersed in the liquid to be filtered, and a shaft wall connected to the discs forming a circular cylindrical filtrate chamber, which extends centrally through the discs. A rigid stationary partition wall extends in the filtrate chamber dividing the latter into at least two axial channels. The partition wall is spaced from the shaft wall and arranged such that all of said axial channels receive various fractions of filtrate, respectively. Filtrate discharge means is provided for discharging said fractions of filtrate respectively from the respective axial channels, such that the pressure prevailing in the filtrate of each channel is at least substantially as high as atmospheric pressure.
Claims8
An apparatus for filtering liquids, such as fiber pulp suspensions, comprising:
- at least one annular hollow filter disc with side walls covered with filter material adapted to be at least partly immersed in a body of a liquid to be filtered and arranged substantially transverse to a horizontal axis extending centrally through the filter disc;
- means for rotating the annular hollow disc about the horizontal axis;
- shaft wall means connected to the filter disc and forming a circular cylindrical chamber, which extends centrally through the hollow filter disc coaxial with the axis and which communicates with the interior of the hollow filter disc;
- means for creating a pressure difference between the body of liquid to be filtered and the interior of the hollow filter disc, such that a filtrate of the liquid is forced through the filter material into the hollow filter disc and passed therefrom into the cylindrical chamber;
- spray nozzle means for cleaning the filter material;
- rigid stationary partition wall means extending axially in the cylindrical chamber and dividing the latter into at least first and second adjacent axial channels, which are partly defined by the shaft wall means, wherein during operation, the second axial channel of the first and second adjacent axial channels, as seen in the direction of rotation of the filter disc, receives a purer filtrate fraction than that of the first axial channel of the two adjacent channels;
- the partition wall means being radially spaced from the shaft wall means and arranged, such that all of the axial channels receive various fractions of filtrate, respectively, during operation;
- filtrate discharge means adapted to discharge the fractions of filtrate separately from the respective axial channels, such that the pressure prevailing in the filtrate of each channel is at least substantially as high as atmospheric pressure;
- the filtrate discharge means being adapted to maintain the axial channels at least partly filled with air;
- and
- pressure control means for keeping the pressure in the purer filtrate fraction in the second channel somewhat higher than the pressure in the less pure filtrate fraction in the first channel, where communication between the adjacent channels takes place.
An apparatus for filtering liquids, such as fiber pulp suspensions, comprising:
- at least one annular hollow filter disc with side walls covered with filter material adapted to be at least partly immersed in a body of a liquid to be filtered and arranged substantially transverse to a horizontal axis extending centrally through the filter disc;
- means for rotating the annular hollow disc about the horizontal axis;
- shaft wall means connected to the filter disc and forming a circular cylindrical chamber, which extends centrally through the hollow filter disc coaxial with the axis and which communicates with the interior of the hollow filter disc;
- means for creating a pressure difference between the body of liquid to be filtered and the interior of the hollow filter disc, such that a filtrate of the liquid is forced through the filter material into the hollow filter disc and passed therefrom into the cylindrical chamber;
- spray nozzle means for cleaning the filter material;
- rigid stationary partition wall means extending axially in the cylindrical chamber and dividing the latter into at least two axial channels, which are partly defined by the shaft wall means;
- the partition wall means being radially spaced from the shaft wall means and arranged, such that all of the axial channels receive various fractions of filtrate, respectively, during operation;
- and
- filtrate discharge means adapted to discharge the fractions of filtrate separately from the respective axial channels, such that the pressure prevailing in the filtrate of each channel is at least substantially as high as atmospheric pressure.
Dependencies are inferred from the claim text.