Improvements in Apparatus for Filtering Polluted Waters and other such Liquids.
Year: 1891

page_text: Date of Application, 30th Sept., 1891
Complete Specification Left, 30th June, 1892-Accepted, 3rd Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Filtering Polluted Waters and
other such Liquids.
I, FRANK PULLEN CANDY of 56 Nightingale Lane Balham in the County of
Surrey Sanitary Engineer do hereby declare the nature of this invention to be as
follows:-
My invention consists in an apparatus, preferably a cylinder provided with a
medium through which the liquid filters, and with one or more inlets and outlets
for the liquid, for filtering purposes and cleaning the filter, and with an arrange-
ment for stirring up and agitating the filtering medium in the operation of cleaning.
The filtering medium I use is one having a light specific gravity such as sawdust,
so that when the agitating arrangement is at work the medium shall, by its action
and the aid of a reverse current of the liquid be suspended and agitated in the
liquid whereby the filter can be easily and effectually cleansed from the impurities
retained in the operation of filtering. When I provide a cover for keeping the
filtering medium in position I arrange to have it capable of being raised, in order
to enable the cleansing operation before mentioned to take place. This cover also
serves to regulate the amount of compression of the filtering medium.
Dated this 28th. day of Sentember 1891.
F. PULLEN CANDY.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Filtering Polluted Waters and
other such Liquids.
I, FRANK PULLEN CANDY of 56 Nightingale Lane Balham in the County of
Surrey Sanitary 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:-
My invention has for its object the manufacture of a filtering apparatus for the
removal of matter from polluted waters or other such liquids, the said apparatus
being provided with a novel means whereby it can be easily efficiently and
economically cleansed of the matter retained in the filtering material during the
operation of filtering.
In order that my invention be more easily understood I have attached hereunto
one sheet of drawings.
Referring to the drawing,
Fig. 1 shows the filtering tank A, which is preferably a cylinder, B is a
perforated plate or plates forming the bottom support for the filtering material, the
said plate being supported on the block B' and the radial blocks B2 shown by
dotted lines. U is a vertical shaft carrying the agitating blades C', C® are
stationary baffling arms fixed on the sides of the filter A, C is a bevel wheel on
the shaft C by means of which and bevel wheel C³ and the shaft C' and cranked
handle C³, the vertical shaft C together with the agitating blades C' is revolved
during the operation of cleansing the filter. D is a support for carrying the
revolving apparatus. E is a perforated plate which forms the cover for the filtering
material, the plate E is attached to the hollow shaft E, and the hollow shaft E
together with the perforated cover E can be raised and lowered at will by means of
the cog wheel E which engages in the cogged plate E, the said cogged plate Es
being attached to the hollow shaft E', the shaft E' and the cranked handle E

page_text: ماء:
to
serving to revolve the cog wheel E². F is a support which serves
guide E. N is a flange attached to the filter tank A in order to prevent a scour of
water down or up the sides of A, and P-is a flange against which the cover E can be
raised. I employ the flange P against which the circumference of the perforated
plate or plates E is raised, in order to prevent the filtering material being carried
away between the circumference of E and the side of the filter A by the upward
flow of water. R is a ratchet wheel. The filter as shown is constructed to filter
in a downward vertical direction and when being cleaned the water is reversed to
an upward vertical flow. H is the inlet for the unfiltered water which, the
valves K' and M! being closed, passes down through the filtering material, the said
filtering material being placed between the perforated plates E. and B, after
percolating through the filtering material the water flows away through the pipe L.
To clean the filter the valves Hand L' are closed and the valves K' and M' are
opened, at the same time the cover E is raised up to the flange P, and the shaft C
together with the blades C' are set in motion, the result being that the special
filtering material of light specific gravity as hereafter described, is suspended in the
water within the increased space B to P, and being swirled round by the blades C¹
each particle of the filtering material is rubbed one against the other, the retained
suspended matter being thereby detached and at once free to escape and be carried
by the flow of water through the perforated plate or plates E and away through
the outlet pipe M, the water entering the filter through the pipe K. When the
water issues from the pipe M in a clear condition the cleansing is complete. The
blades C are ceased from being revolved, and the valves K' and M¹ are closed, the
valve L¹ is opened and the cover Eis lowered to the level the filtering material
assumes when the filter contains no water, the filtering material may if required:
be compressed by forcing the cover E down upon it, the valve H' is then
opened and filtering proceeds as before, when the filter has again slowed to
such an extent as to make it desirable to clean the filter, the filter is again
cleansed, and so on.
Sometimes instead of filtering the water downwards and cleaning the filter by
reversing the flow to an upward one, I filter the water upwards and clean with a
downward flow, in which latter case the water to be filtered would enter through the
pipe K and leave through the pipe M, the reverse current for cleaning the filter
would enter at H, the dirty water flowing out at L, the pipe L would be raised by
means of a bend to the level of the flange P so as to keep the filter full of water
up to the flange P (that is to the highest position of the cover) when it is being
cleaned. I sometimes clean the filter without reversing the flow of water and
provide a separate outlet for the dirty water or have the same outlet for the dirty
water as for the filtered water and provide a junction in the discharge pipe so that
I may turn the filtered and dirty water to different points.
4
The filtering material I use is one having about the same specific gravity as
water, I preferably employ one having a lighter specific gravity than water, such
as cork granules, when I use a filtering material having an equally light or a
lighter specific gravity than water I employ a cover as shown at E to keep the said
filtering material in position, but when I use a filtering material having a slightly 4
greater specific gravity than water such as sawdust granules, which become sodden
with water and therefore of a slightly greater specific gravity than the water, I
sometimes do not use a cover and place a perforated plate over the outlet for the
dirty water, preferably increasing the size of the outlet or using a number of
outlets, in other respects the cleaning arrangement must be as before described,
that is to say there must be an agitating apparatus and sufficient height and space
in the filter for the agitating apparatus when in motion to stir up and suspend the
filtering material to a higher level in the water than it occupies when the machine
is filtering.
It will be evident that instead of agitating the filtering material and raising and 5
lowering the cover by manual labour I can arrange for the work to be performed
by motive power such as a steam or gas engine. When I am filtering a liquid of a

page_text: different specific gravity to water the specific gravity of such liquid is to be the
standard to which the specific gravity of the filtering material is to be compared.
When I require a still greater degree of purification than is obtained by this filter
I afterwards pass the filtered water through an oxidizing medium.
I would have it understood that I do not limit myself to the exact form of filter
described and shown, as it will be evident that many different mechanical forms
of apparatus may be devised to arrive at the same results, but 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 filtering apparatus substantially as described and shown.
2. In a filtering apparatus, a cover that can be raised and lowered for the
purpose of enabling the filtering material to be suspended in the liquid when the
filter is being cleaned combined with a. filtering material of about the saine specific
gravity as the liquid to be filtered and an apparatus for agitating the said
filtering material and one or more inlets and outlets for the liquid.
3. In a filtering apparatus a cover that can be raised and lowered for the
purpose of enabling the filtering material to be suspended in the liquid when the
filter is being cleaned combined with a filtering material of no greater specific
gravity than the liquid to be filtered and an apparatus for agitating the said
filtering material, and one or more inlets and outlets for the liquid.
4. In a filtering apparatus a cover that can be raised and lowered for the purpose
of enabling the filtering material to be suspended in the liquid when the filter is
being cleaned combined with a filtering material of about the same specific gravity
as the liquid to be filtered and an apparatus for agitating the said filtering
material.
5. In a filtering apparatus a cover that can be raised and lowered, for the
purpose of enabling the filtering material to be suspended in the liquid when the
filter is being cleaned combined with a filtering material of no greater specific
gravity than the liquid to be filtered and an apparatus for agitating the said
filtering material.
6. In a filtering apparatus, a filtering material which when in use shall be of an
equal or slightly greater specific gravity than the liquid to be filtered, combined
with an apparatus for agitating the filtering material whereby in the operation of
cleaning the filter the filtering material shall be suspended in the liquid.
7. In a filtering apparatus, a filtering material which when in use shall be of an
equal or slightly greater specific gravity than the liquid to be filtered combined
with an apparatus for agitating the filtering material whereby in the operation of
cleaning the filter, the filtering material shall be suspended in the liquid, and one or
more inlets and outlets for the liquid.
8. In a filtering apparatus, a filtering material and an apparatus for agitating
the filtering material, whereby in the operation of cleaning the filter, the filtering
material shall be suspended in the liquid.
9. In a filtering apparatus, & filtering material of an equal or less specific
gravity than the liquid to be filtered and means for agitating and suspending the
filtering material in the liquid.
10. In a filtering apparatus a filtering material of organic origin of about the
same specific gravity as the liquid to be filtered, and means for agitating and
suspending the filtering material in the liquid.
Dated him noth dow of I 1900
F. PULLEN CANDY.