PLAQUES-SUPPORTS D'ELEMENTS FILTRANTS POUR FILTRES-PRESSES

FILTER SUPPORT OF PLATES FOR FILTER PRESSES AND FILTERS

Abrégé anglais

ABSTRACT OF THE DISCLOSURE:
A filter support of plates for filter presses and filters
for filtering over a filter wall, for instance over a filter cloth
or filter paper provided with regularly oriented projections, the
upper surfaces which are in contact with the filter wall, provided
with grooves.

Revendications

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. A filter support for a plate for filter presses
and filters for filtering over a filter wall, said support
comprising regularly oriented projections of geometric shape,
said projections having upper surfaces which are in contact
with the filter wall and which are provided with grooves.
2. A filter support for a plate for filter presses
and filters for filtering over a filter wall, said support
comprising: a base; spaced projections upstanding from said base
and terminated by substantially flat upper surfaces adapted to
come in contact with said filter wall, and grooves cut through
said flat surfaces.
3. A support as claimed in claim 1, wherein said pro-
jections and upper surfaces are evenly spaced from one another
in parallel rows and said grooves are inclined with respect the
orientation of said rows.
4. A support as claimed in claim 3, wherein said
grooves are inclined at 45° with respect to said orientation.
5. A support as claimed in claim 3, wherein said
grooves are inclined alternatively at 45° and 135° with respect
to said orientation.
6. A support as claimed in claims 1, 2 or 3, wherein
said surfaces are square and lie in a common plane.

Description

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The present invention relates to a filter support of
plates for filter presses and filters for filtering over a fil-
ter wall, for instance over a filter cloth or filter paper, which
filter support is advantageously made of plastics. The draining
arrangement of the filter support comprises regularly oriented
projections of geometric shapes.
At present, supports for the plates for filter presses
and filters with different types of draining arrangements are
used. As a draining arrangement, a system of projectlons support-
ing the filter wall and a system of channels serving for removal
of filtrates ~etween said projections is employed. A commonly
used draining arrangement uses vertical grooves at both sides
of filter press plates, particularly wooden filter press plates
and plates made of polypropylene. Some filter press plates made
of plastics are also provided with inclined grooves, with cylin-
drical projectlons and projections in the shape of truncated
. pyramids. Another draining arrangement uses truncated pyramids
with channels with two different depths for removal of filtra-
tes.
All of the above-mentioned draining arrangements ha~e
the common drawback that the surface of the projections on which
the filter wall bears is smooth, flat or slightly convex and the
filter wall bears on this surface rather tightly due to the
filter pressure. At places where the filter wall is in contact
with the projections of the draining arrangement, the speed of
filtration is reduced, such reduction being larger, the thinner
the filter wall is and the larger the surface of the projections.
Recently, thinner~ harder and rather denser filter walls are used
which are made of synthetic fibers. These walls are smoothed by
calendering them from one or both sides in order to achieve
anti-adhesive properties to filter cakes. This kind of filter
wall requires a particularly effective draining arrangement.
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It is an object of this invention to provide a support
for the plates of filter presses and filters for flltering over '~
a filter cloth or filter paper, which passes the fil~rate more
uniformly over the whole filtering surface. The filter support
according to this invention is provided with regularly oriented
projections of geometric shapes, for instance cylinders, prisms,
truncated pyramids or conesj the upper surfaces of which are
flat or slightly convex, the upper surfaces of this draining
arrangement, which are in contact with the filter wall, are pro-
vided with grooves.
The filter support according to this invention with ,
grooved upper surfaces of projections of the draining arrange-
ment énables a good removal of the filtrate even from places
where the projections are in contact with the filter wall. The
grooves can extend in one direction or in two directions which
are disposed at an acute or a right angle with respect to each
other. It is possible to have the grooves extended in directions
which differ from the directions of the warp and weft of the
filter cloth so that individual fibers of the filter cloth obtain
~20 a better support.
In accordance with the broad concept of one aspect of
the invention, there is provided and claimed herein a fi-lter
support for a plate for filter presses and filters for filtering
over a filter wall, the support comprising regularly oriented
projections of geometric shape, the projections having upper
surfaces which are in contact with the filter wall and which are
- provided with grooves.
In accordance with the broad concept of a further as-
pect of the invention, there is provided and claimed herein a
filter support for a plate for filter presses and filters for
filtering over a filter wall, the support comprising: a base,
spaced projections upstanding from the base and terminated by
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substantially flat upper surfaces adapted to come in contact
with the filter wall, and grooves cut through the flat surfaces.
Examplary embodiments of a filter support according
to this invention are indicated diagrammatically in the atta-
ched drawing, wherein:
Fig. 1 is a top view of a first embodiment of a
draining arrangement wherein the upper surface is provided with
grooves extending in one direction, a further view below the
top view showing a cross section thereof ;
Fig. 2 is a top view of a second embodiment of a e
draining arrangement, the upper surface of which is provided with
grooves in two directions, a further view below the top view
showing a cross section thereof.
The support for plates of filter presses and filters
according to Fig. 1 is provided with regularly oriented projec-
tions 1, having the shape of truncated pyramids arranged in
parallel rows with channels 3 between the projections 1, the
channels`3 extending at right angles with respect to each other.
The pyramids in each row are disposed at a uniform distance from
each other.- The upper surface of the projections 1 of this
draining arrangement of the filter support is provided with
spaced parallel grooves 2 extending in one direction. The grooves
2 are at an angle of 45 with respect to the same one side of
each pyramid. The projections 1 having the shape of truncated
pyramids have dimensions of 8 x 8 mm, a height of 4 mm, the
grooves 2 are 0,5 mm wide and 0,5 mm deep. The channels 3 have
a depth of 4 mm and width of 6 mm.
The support for the plates of filter presses and
filters according to Fig 2 has also regularly oriented projections
1 with channels 3 between these projections 1, the latter being
disposed as in Fig. 1. The upper surface of the draining arrange-
ment of the filter support, which is in contact with the filter
wall, has two sets of grooves 2, extending in two different direc-
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tions. The graoves 2 extend at angles of 45 and 135 with
respect to the channels 3. The dimensions of grooVes 2 of
channels 3 and projections 1 of the draining arrangement are
the same as in Fig. 1. . .
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