Improvements in the Discharge of Liquids upon Filters.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in the Discharge of Liquids upon Filters.
I, THOMAS CAINK, of Fort Royal Hill, in the City of Worcester, Civil Engineer,
do hereby declare the nature of this invention to be as follows:-
In order to secure the best results in the filtration of water sewage or other
liquids, it is necessary that the liquid should be brought into contact with every
portion of the filtering material, so that every part of the material may have its
proper share of the work that has to be done. It is also usually advantageous
that the atmospheric air should have as free access as possible into the body of the
filter. The common method of causing the liquid to pass along and overflow
channels near the surface of the filter allows the liquid to immediately enter the
filter near the edge of the channel, the consequence is that unless the channels
are placed very near to one another over the entire surface of the filter (which
would be exceedingly costly) a large portion of the filtering material is not utilised
by contact with the liquid unless the outlet from the filter is closed and the liquid
allowed to accumulate in the filter tank or bed. The object of the invention,
which forms the subject of this application for Letters Patent, is to so discharge
the liquid on to the surface of the filter that the whole of the material shall be
utilised by contact with the liquid and at the same time assist in driving air down
with the liquid into the body of the filter, and further to render unnecessary the
accumulation of liquid in the filter whereby for the time being the air is excluded.
In order to accomplish these purposes I discharge the liquid upon the filter from
a travelling perforated pipe or spreader somewhat similar to that attached to the
rear of street watering carts. The spreader may stretch entirely across the filter
bed and be fed from channels on one or both sides thereof. It may be caused to
travel to and fro over the filter upon flanged wheels running upon rails moved
by hand power, machinery through gearing, by electric or other motor or prefer-
ably by the re-action of the liquid itself in issuing from the spreader. I preferably
arrange the spreader that its extremities terminate in syphons the short legs of
which dip into the side or other channels from which it is fed. The spreader is
thus fed by syphoning the liquid from the channels. When the movement of the
spreader is obtained by the reaction of the liquid as above mentioned I divide the
spreader longitudinally into two chambers and provide a row of jets from each
chamber pointing in opposite directions. Each chamber is fed through a separate
valve from the syphon, these valves open and close alternately automatically
so as to reverse the direction of the discharge each time the spreader reaches the
end of its traverse. This causes the spreader to run to and fro delivering the
liquid like rain over every part of the filter so long as the channels in which
the syphon's move are fed with the liquid. Any other method for reversing the
direction of the spreader may be employed. In order better to ensure the restart-
ing of the apparatus when it has reached either end of its traverse I cause it to
strike against spring or other buffers whereby the energy of the momentum is

page_text: for the moment stored and again immediately employed in overcoming the inertia
of the apparatus for restarting it on its return journey. The filter beds may be
made circular and fed by means of rotary spreaders driven by the reaction of the
liquid as in the case of the apparatus known as the Barker's mill.
Dated this 18th day of August 1897
I, THOMAS CAINK, of Fort Royal Hill, in the City of Worcester, Civil Engineer,
do hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:-
In order to secure the best results in the filtration of water, sewage or other
liquids, it is necessary that the liquid should be brought into contact with every
portion of the filtering material, so that every part of the material may have its
proper share of the work that has to be done."
It is also usually advantageous that the atmospheric air should have as free
access as possible into the body of the filter.
The common method of causing the liquid to pass along and overflow channels
near the surface of the filter allows the liquid to immediately enter the filter near
the edge of the channel, the consequence is that unless the channels are placed very
near to one another over the entire surface of the filter (which would be exceed-
ingly costly) a large portion of the filtering material is not utilised by contact with
the liquid, unless the outlet from the filter is closed and the liquid allowed to
accumulate in the filter. The object of this invention is so to discharge the liquid
on to the surface of the filter that the whole of the material shall be utilised by
contact with the liquid and at the same time assist in driving air down with the
liquid into the body of the filter, and further to render unnecessary the accumla-
tion of liquid in the filter whereby for the time being the air is excluded. In
order to accomplish these purposes I discharge the liquid upon the filter from a
travelling perforated pipe or spreader somewhat similar to that attached to the
rear of street watering carts. The spreader may stretch entirely across the filter
bed and be fed from channels on one or both sides thereof.
It may be caused to travel to and fro over the filter upon flanged wheels running
upon rails, moved by hand power, machinery, through gearing by electric or other
motor or preferably by the re-action of the liquid itself in issuing from the spreader.
I preferably arrange the spreader that its extremities terminate in syphons, the
short legs of which dip into the side or other channels from which it is fed.
The spreader is thus fed by syphoning the liquid from the channels.
When the movement of the spreader is obtained by the re-action of the liquid
as above mentioned I divide the spreader longitudinally into two chambers and
provide a row of jets from each chamber pointing in opposite directions. Each
chamber is fed through a separate valve from the syphon, these valves open and
close alternately automatically, by the spindle of lever striking against a buffer
so as to reverse the direction of the discharge each time the spreader reaches the 4
end of its traverse.
This causes the spreader to run to and fro delivering the liquid like rain over
every part of the filter so long as the channels in which the syphons move are fed
with the liquid.

page_text: Any other method for reversing the direction of the spreader may be employed.
In order better to ensure the re-starting of the apparatus when it has reached
either end of its traverse I cause it to strike against spring or other buffers,
whereby the energy of the momentum is for the moment stored and again imme-
diately employed in overcoming the inertia of the apparatus for restarting it on
its return journey.
The filter beds may be made circular and fed by means of rotary spreaders
driven by the re-action of the liquid as in the case of the apparatus known as the
Barker's mill.
Plate 1, shews the apparatus as applied to a rectangular filter. A is the distri-
butor. B, B, the side channels conveying the liquid. C, C, the reversing valves.
D, D, the levers which upon the distributor reaching either end of the filter strike
against the buffers E, E, E, E, closing the valve then open, and opening the valve
then closed.
Plate 2, shews the apparatus applied to a circular or other filter where reversing
valves may be dispensed with. A is the distributor extending from the centre
to the outside of the filter and having a syphon B at the centre for conveying the
liquid from the supply pipe C.
Plate 3 shews another method of conveying the liquid from the supply pipe A
to the distributor by means of annular tank 13 which rotates with the distributing
arms C, C.
If instead of giving motion to the distributor by the reaction of the liquid
issuing therefrom it is intended to drive it by an electric motor, the motor may be
fixed to the distributor and geared to one of the wheels, the current being conveyed
along the rail or otherwise.
By this means the liquid may be taken from the channel or conduits at the same
level as the filters or may be lifted from a lower level if the moveable pipes which
take the liquid from the channel to the distributing limb have a vertical opening
facing the direction in which the distributor is moving.
Having now particularly described & ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. The distribution of liquids over sewage, water or other filters, by movable
distributors substantially, as and for the purpose herein before described.
2. The use or employment in conjunction with movable apparatus for the dis-
tribution of liquids on to filters, of a syphon for conveying the liquid to the
distributing pipe.
3. The employment of the re-action of a liquid flowing from a pipe or vessel to
give motion to apparatus for the distribution of liquids on to filters substantially
as described.
4. The use or employment in conjunction with apparatus for the distribution of
liquids on to filters, of reversing valves substantially as and for the purpose herein-
before described.
5. The use or employment in conjunction with apparatus for the distribution of
iquids on to filters of an annular tank substantially as and for the purpose herein-
before described.