Improvements in Apparatus for the Filtration of the Feed Water of Marine and other Boilers.
Year: 1892

page_text: Date of Application, 22nd Sept., 1892
Complete Specification Left, 22nd June, 1893-Accepted, 5th Aug., 1893
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for the Filtration of the Feed Water of
Marine and other Boilers.
I, ANTHONY HARRIS, of Vulcan Works, Middlesbro', in the County of York,
Engineer, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to provide an apparatus by which the impurities
which contaminate the feed water of steam boilers, more particularly those of
surface condensing engines, may be readily removed or arrested, and it may be
employed either in conjunction with a feed water filter of any description, or may
take the place of, and act as, a filter and the feed water may pass direct from it
into the boiler.
The opening out and cleansing of filters for boilers usually occupy a considerable
time, and to obviate this I arrange the filter in such a manner that it may be
thoroughly cleansed without opening it out at all, except at rare intervals when the
filtering medium becomes worn out or so saturated with unremovable impurity as
to fail to act as required.
With these objects, I employ one or more cylinders (preferably two) with closed
top and bottom and furnished with inlet and outlet valves for the feed water
and means of discharging the sludge or impurity and suitable cleaning doors, and
also a cock or valve for injecting steam or hot water at the required time.
Each cylinder is provided with a piston rod and a suitable number of perforated
or gauze covered pistons or diaphragms, the positions of which are controlled by
guides and springs, the bottom diaphragm resting on a projection provided for
that purpose and the top one preferably secured in position and immovable.
Between the diaphragms, clastic or semi-elastic filtering material (that is, specially
prepared sponge) is provided.
The springs are employed to keep the diaphragms as nearly equidistant as
possible and to prevent the whole mass of sponge or other filtering material being
forced in a plug to the end of the cylinder by the rush of water, as the feed
passes through, the result of which would be that the sponge would be unduly
compressed, and the impurity squeezed. out of it and it would pass away along
with the filtered water, and again contaminate it.
22
Very minute pressure is required to force the soaps of cylinder oils, or fatty acids,
through almost any known filtering medium; preferably, therefore, I employ, in
conjunction with this filter, the "sentinel valve described in my Patent
No. 68011, which, upon the desired pressure being exceeded, passes the feed
water direct to the boilers and, at the same time, informs the attendant that the
filter is foul.
To cleanse the filter, the inlet and outlet valves are closed, the sludge opened,
and the pistons or diaphragms moved by means of the rod till they compress the
springs and squeeze the filtering medium between themselves and the fixed
perforated diaphragms, and, while squeezed, steam or hot water is passed through
the medium by the appliances for that purpose and passes out at the sludge.
The sludge is then shut, the piston rod lowered to its normal position and the
springs expanding replace the diaphragms in their former position, the inlet and
outlet valves open and the filter resumes its duty.
It is obvious that the filter may vary much in shape, that it may be arranged in
combination with, or form an integral part of, a subsidiary filter, that it may be
reversed and work the opposite way, or horizontally, that the diaphragms may be
flat or curved or conical, that various equivalents may be used for the springs or
that the diaphragms may be held apart and moved by right and left handed or
other screws or their equivalents.

page_text: In small filters, only one moving diaphragm may be used.
In some cases, the inlet and outlet valves may be provided with self-closing
valves or grates so that the pistons may move the entire length of the cylinder in
cleansing, and, in this case, the piston or diaphragm may be formed without
perforations or provided with valves like air pump buckets.
Dated this 20th day of September 1892.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for the Filtration of the Feed Water of
Marine and other Boilers.
I, ANTHONY HARRIS of Vulcan Works, Middlesbro' in the County of York,
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:-
The object of this invention is an apparatus by which the impurities which
contaminate the feed water of steam boilers especially those of surface condensing
engines may be readily removed, arrested or separated, and one that may be
employed either in conjunction with a feed water filter of any other description or,
may take the place of and act as a filter, and the feed water may pass direct from
it into the boiler. The opening out and cleansing of filters for boilers usually
occupy a considerable time and it is very difficult to attend to this work especially
when at sea in bad weather. My present invention is designed to arrange a filter
in such a manner that it may be thoroughly cleansed without being opened at all
except at rare intervals when the filtering medium becomes worn out or so saturated
with unremovable impurities as to fail to act as required.
The invention is best described by aid of the accompanying drawing which
shows 2 vertical sections of a filter; Figure 1 in its ordinary condition for filtering,
Figure 2 when compressed for cleansing purposes. 1 is a cylinder (preferably I
employ two of these). It is closed at top and bottom with cylinder lids in the
ordinary manner. 2 and 3 are delivery and inlet valves. 4 sludge valve,
5 cleansing doors, 6 an opening into the cylinder from a steam pipe from the boiler
for injecting steam or hot water. This steam pipe is supplied with a stop cock and
is used as required. 7 is a piston rod, and 71 7², etcetera, a series of pistons fitting
the cylinder; 88 a series of springs surrounding the piston and separated from
each other by partitions 9 joined in the case of the central piston 73 direct to the
piston so that the piston and partition form a single disc. but in other cases the
partition is joined to the disc by sleeves 10. These sleeves 10 are long enough as
regards the two connected with the pistons on opposite sides of the central piston to
contain one of the springs closely compressed, or, if there be an even number of
pistons, then the two central sleeves unitedly contain a sufficient space to hold one
spring. The two sleeves beyond these each contain besides this space an additional
space nearly sufficient to accommodate another spring and so on. This will be seen
more clearly in Figure 2 where the springs are all tightly compressed. Each
piston or diaphragm is perforated throughout its area and is covered with metallic
gauze or other coarse filtering material in such manner that the gauze only lies
against the piston at sundry points or lines, the space below being hollowed and
connected with the perforations or as shown in the sketch cut away altogether.
Between the various pistons and sometimes between the top and bottom ones and
the top and bottom of the cylinder, I loosely pack the spaces with sponge or other
compressible filtering material.
The mode of action is as follows-
The filter being built up as set forth in Figure 1, the lid is fixed in place and the
water passed through it circulating preferably unwando form the males

page_text: valve 2. It will be noticed that valve 3 does not enter into the filter itself but
about the middle of a sludge chamber below the filter, this sludge chamber being
separated from the filter by the bottom piston. This sludge chamber is usually.
kept emptied and not filled with filtering material; sludge can therefore settle in it.
When the filter begins to clog, the piston rod 7 is drawn up in the manner set forth
in Figure 2, the delivery and inlet valves having previously been closed. The
water being unable to escape from between the filters in any other manner passes
downwards to the sludge chamber, the great pressure caused by the compression
forcing out the dirt to a great extent with the water; this water is run off by the
sludge valve. In order to further assist this action, steam or hot water from the
boiler or both, hereafter spoken of under the simple word steam, is led in at 6, and
the top chamber which is preferably kept clear of filtering material gets filled
with steam under high pressure and this steam forcing its way through the
diaphragms 71 72, etcetera, forces the dirty water and dirt down into the sludge
chamber; water being now passed through the valve 2 downwards for a short time
and the sludge which has accumulated is passed out at the sludge cock; the pistons
are now let down into the position shown in Figure 1, the sludge cock closed and
the valves opened. The doors 5 are sometimes used for cleaning out the top
and the bottom chamber. In connection with this filter I prefer to use the sentinel
valve described in my British Patent No. 6801" this having the advantage that,
when the desired pressure on the filtering medium is exceeded, the feed water
passes direct to the boiler and at the same time the attendant is informed by the
call actuated by the sentinel valve that the filter is foul. It is obvious that the
filter may vary much in shape and that it may be and in fact usually is, combined
with other filters when the water is desired to be very pure. It may be reversed
so as to work the opposite way or be horizontal or inclined. The diaphragms may
be flat, dished or conical, and heavy weights can take the place of the springs, or
the diaphragms may be held apart and brought up to each other by right and left
handed screws or equivalent mechanism. Further, the number of diaphragms is
immaterial, for very small filters one only is requisite. This one can be screwed
up tight for cleaning purposes to one or to each end of the cylinder alternately.
The inlet and outlet valves may be provided with self closing valves or grates so
that the pistons may move the entire length of the cylinder in cleansing instead of
only as far as set forth in Figure 2.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a filter, the combination of a chamber, a series of one or more movable
perforated diaphragms in that chamber, a packing of loosely packed filtering
material and means whereby the diaphragm or diaphragms can be brought up with
strong pressure against a partition or wall whereby, when such pressure is applied,
the dirt and water are squeezed out into the other end of the chamber.
2. A filter formed of a chamber or chambers containing compressible filtering
material, for instance, sponge, through which the water to be filtered is passed, and
apparatus connected therewith whereby, without opening the filter, the filtering
material may be compressed or squeezed and the exuding liquid or mud drained or
run off.
3. The apparatus for alternately compressing the filtering mechanism and for
permitting it to expand substantially as described and illustrated.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.