Year: 1888

page_text: I, WILLIAM OLIPHANT, residing at Jersey City, in the County of Hudson and
State of New Jersey, one of the United States of America, 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
-
This invention relates to purification of water or other liquid by mechanical
filtration under pressure, and is adaptable also to assisted precipitation of impurities
by coagulants
In practice heretofore, the process of filtration has been periodically interrupted by
reason of the release from pressure in the apparatus and laborious method required
for removing and substituting the fouled portion of the filter bed with fresh material
at intervals which are frequently necessary
The object sought is to economize the time and labor involved in the said practice,
and to render the cleansing of the filtrate more effectual by the greater frequency of
the renewing operation made practicable
The invention, therefore, consists in subjecting the liquid to two or more separate
filtrations, first, through a partly horizontal bed of comparatively coarse material
which arrests the larger percentage of impurities, and which by reason of its
horizontally directed current is made capable of frequent renewing by automatic
means as hereinafter described, without essential interference with the continuous
action of filtration, and second, through a bed or beds of comparatively fine material
in which upward filtration is preferably employed, and which takes up the remaining
impurities, the necessary periods of renewal therein being of less frequent require
ment, and then only involving momentary interruption of filtration withont a release
of pressure, the means of renewal being also automatic, promoting a substantially
constant action of the apparatus
Referring to the Drawings
Figure 1, 'is a longitudinal sectional elevation on the line, x, x, figure 2, of the

page_text: Figure 2, cross-section of the filter, on the line y, y, figure 1
Figure 3, a partial horizontal section on the line, z, z, figure 1
Figure 4, a detail view
Figure 5, is longitudinal sectional elevation of a modified form of construction
of the filter,
ind
Figure 6, a detail view of the cleansing pipes therein
The filtering vessel, A, 1s subdivided into chambers C, and, D, by means of a
partition B, ind perforated or porous diaphragm, E, figures 1, 2, 3 and 5
The sud
diaphragm, E, is preferably of the construction shown, composed of a double
perforated plate or wire netting containing gravel or other like filling, but may be
otherwise constructed if preferied, as in the form of a single perforated plate, wire
netting, or porous mineral or other diaphragm The construction shown in figures 1,
2 and 3, consists of in upper and a lower perforated plate, each having oblong
perforations, a, (figure 3,) braced together by stays, 6, secured to the filter shell
about their margins, and suspended firmly in place by means of brace rods c, to
prevent displacement under the weight of the filtering bed to be sustained thereupon
The filling, d, of gravel or the like, is of a grade of larger size than the orifices of the
plates which are to hold it, and his the function of preventing the passage of the fine
filtering material downward out of the chamber, D, especially during the washing out
and replacing operation applied to said material as hereinafter described
E is an pron of sheet metal for retaining the filtering material of the lower
chamber in place and directing the current throughout the latter before its access to
diaphragm, E
The part, E, in figure 5, is shown as modified in the form of a perforated or wire
cloth diaphragm extending continuously from the lower edge of the partition, B, to
The
the opposite end of the filter, and sustained by the transverse rods, a³
diaphragm, E, in this instance may be constructed of different grades or sizes of
mesh or perforation is for instance, a finer size at, E², gradually increasing to a
courser size at, Es An even distribution of the filtrate is thereby promoted in its
passage from the horizontal portion of the chamber, C, to the suspended bed, D
F', higure 1, is a force pump shown as an illustration of a suitable source of liquid
supply under pressure G, is the suction pipe, and, H, the delivery pipe of sud pump,
the latter pipe entering preferably, at the top of the chamber, C, through nozzle, 1,
and the liquid being thrown against the cylindrical structure, J, is spread laterally,
and the current equally distributed at its point of entrance to the filtering bed in, C,
at the top thereof
J, K, L, are charging funnels on hoppers through which the filtering material is
introduced at times when the apparatus is relieved of pressure for the purpose, and
in sufficient quantities to supply the filter for a considerable length of time
The
caps, e, f, g, of said funnels are removable by means of screw threads, yokes or other
well known devices, whereby, they are pressure tight when adjusted in place
M, is bifurcated inter-prolongation of the filter delivery pipe, N, serving as a
sepuito to insure against particles of matter from the bed in compartment, D, being
carried over into sud delivery pipe The structure of the part, M, is better illustrated
by figures 2 and 4 The same consists of combined semi-tubular sections, h, t, having
in interposed perforated plate, 3, subdiving the interior of said sections The lower
section being perforated on its exterior and filled with gravel or the like, allows the
inflow of the purified liquid there-through and into pipe, N The induction and eduction
liquid pipes, H, and, N, are each provided with suitable valves, O, P, respectively,
adapted to, partly or wholly close and regulate the flowing capacity of said pipes
As a substitute for the outflow pipe, M, a double diaphragm similar to, E,
may be employed as illustrated in figure 5, the same being also filled with gravel
or other granulated filling The space, N', left above is similar in function then
to the upper section in the pipe extension, M, and the granulate of the bed, D,
retained in place, the filtrate separating therefrom before its passage out through
the pipe, N

page_text: The means I employ for automatic replacement of the fouled portions of the
filtering beds, consists in the application thereto of hydraulic force throngh the
several series of washing pipes, k, l m and n, connected through manifolds, ¹, l, n¹,
and pipe, Q, to suitable source of hydraulic pressure, or connected directly to
the pump delivery pipe, H, if desired, as in figure 5 The water thus forced into
the lower or fouled portions of the filter beds, or through the gravel filling of the
diaphragm, E, at such points as are for instance indicited, is permitted to escape
through the discharge or blow-off pipes, o, p, q, located as indicated, or elsewhere
if desirable, and adapted to convey with the outgoing current the lowermost
portions of the filtering mass Such various inflow and outflow pipes are suitably
provided with separate regulating valves and cocks as will be understood by in
inspection of the figure<
In figures 5 and 6, additional washing or cleansing pipes are shown as, t, for
cleansing the gravel filling in, E³, and, n³, for cleansing the vertical portion of
the filter-bed, C The branches of the washing pipes may be constructed of
various lengths to produce currents at various portions of the filter beds, and the
more thoroughly permeate them, but not create an uneven displacement of any
one portion This feature is shown in figure 6, which is a plan view of part
of the pipe branches from, h, alternating in lengths, the remainder of the
cleansing pipes being similarly varied in lengths is indicated at the various
points, a
Suitablo manholes or handholes as, R, R, R¹, R³, ire provided at various parts of
the shell as may afford necessary access to the interior for cleansing or other
obvious purposes
The inholes R', R¹, figure 5, permit the extraction or replacement of the filling
between the diaphragms, E, E', or the repurs of the same conveniently
S, T, are accumulators for receiving and automatically discharging such portions
of air as may rise to the top of the chambers They are provided either with witei
gauges, and hand valves, s, or with automatic balanced discharge vilves, t,
controlled by a float, u, or both The valve, t, shown for illustration, consists of i
piston having a circumferential grooved port, v, adapted to coincide with the port, w,
in the valve casing when the flont is depressed below its normal position, and thereby
open communication between the chamber and the exterioi ur
The
U, is a vessel contuning the congulating agent as sulphate of alumina, the sime
being suspended upon perfor ited sheet, a, within the pressure tight tank
tank, U, is connected at its lower portion beneath said perforated sheet by a tube, 6',
with the suction side of the pump, and at its upper portion by a tube, c', with the
pump delivery pipe, H, through branch, d', or to the filter delivery pipe, N, through
branch, e', thus promoting circulation from the pressure side of sud pump to the
top of the tank, U, and downward through the coagulant, thence to the point of
filtrate supply,
The tubes, b, d, e, are controlled by suitable cochs, f¹, ², h¹
9
The tube, b¹, 15
provided with an indicating drip tube, a¹, of glass, through which the amount of liquid
charged with coagulant may be observed and regulated by cock, f, or by an adjusting
valve, ', the cock, ³, being hept closed
The operation of filtration is as follows The compartments, C, and, D, of the
apparatus being filled nearly to the top with the different grades of filtering material
as specified, said in iterial consisting of sand, pulverized cohe, charcoal, or other well
known filtering substance, through the funnels or hoppers, J, K, L, and said hoppers
closed, the filter is charged with the water or other liquid to be filtered at the desired
working pressure by means of the pump, F The impurities are mechanically
separated in part, uniformly through the courser bed, C, passing first downward, then
horizontally and around the apron or the perforated diaphragm, E', are forced upward
through the diaphragm, E, into and through the finer bed, D, the extreme lower
portion of the latter adjacent to the diaphragm, E, taking up the remaining impurities
Thence the liquid is conveyed out of the filter through the gravel or other sand

page_text: retuning separator in pipe extension M, or through its equivalent device, ď,
figure 5
I find it preferable to employ an upward current in the filtering process, allowing
the current to strike the heavier portion of the bed first, and in the washing out
method which I employ I apply the expelling force to the fouled material, therefore,
at the lower portion of the bed, D, adjacent to the diaphragm, E, through the series
of washing out pipes, The valve, P, may be closed during this operation and the
blow off pipe of pipes, o, are opened, so that said fouled material is horizontally
discharged through pipe, o, allowing the mass of fresh material above to remain
comparatively undisturbed by reason of the great force of horizontal flow from pipes, l,
(figure 1,) and to subsequently settle as the washing operation ceases upon the
diaphragm, E This operation occupies but a brief period and is of rare require-
ment, owing to the preceding filtration which has sepirated the bulk of impurities in
the chamber, C, which, owing to the horizontal current therein, may be subjected to
frequent blowing out of its lower portion by me ins of the series of washing pipes, n,
and blow-off pipe or pipes, p, without miteriilly interrupting the flow of filtrate
through the upper section of its horizontal portion In performing the renewing
operation of the bed, C, it is found preferible to partly close the valve, P, in the filter
discharge pipe and utilize a portion of the filtrate to issist in eliminating the arrested
impurities from the upper is well as the lower portion of said bed, C, and also in
driving down the upper or comparatively new material thereof to replace the
lower
A blow-off pipe, q, is provided at the point shown, intermediate between the point
of washing discharge, p, and the induction point, I, to afford a more direct blow-
curient if desired to cleanse the upper portion of said bed, C
The gravel diaphragm, E, has also like means of washing out by the pipes, m,
(figure 1) or pipes, 1, (figure 5,) entering between the perforated sheets or wire
netting and discharging such impurities as may accumulite through the blow-off
pipe, p
The washing pipes, h, e designed more particularly to disturb and make over the
entire body of the bed, D, when occasioned by the tendency of the water or other
liquid to gradually form channels therein This evil however, is caused largely by an
excess of charged air intro'aced with the liquid, and the function of the accumu-
lators, S, T, is to remove ti > surplus air, the same being occasionally ejected by the
cock, s, or automatic valve, t, as hereinbefore described
A feature of modification consists in that illustrated in figure 5, of intercepting the
inlet cleansing pipe Q, and the outlet cleansing pipes, p, and, 9, with automatic
valves, Q, and p² respectively Both valves open downward and ire counterbalanced
by suitable weighted levers is shown Their function is to utomatically clear the
fouled portions of filtering material when the pressure under which the filtrate 19
passed becomes excessive
Under high pressure, the filtrate current becomes rapid and the beds therefore
foul more rapidly, requiring frequent cleansing An increase of back pressure
resulting from accumulation of separated material will open both valves, Q¹, and, p¹
An upward or counter current is thereby effected through the bed, C, from the
pipe, ³, to the outlet cleansing pipe, Horizontal cleansing currents are effected
through the pipe, n, and such other pipes, k, l, m, &c, as may be desired, according as
their conti olling cocks are left open or closed, and the discharge is effected through
the pipes, g, and, p, by the valve, p¹
For purification in the instance of water, from clay or peaty matters, by means of
sulphate of alumina, or from magnesia salts, by the use of lume, the coagulant 15
placed in the tank, U, figure, 1, as described, and by force of the current admitted
thereto by the tubes, d', or, h', is carried in solution in regulated quantities through
the drip tube, ', to the suction side of the pump F By this means of introduction
the coagulant is thoroughly diffused through the liquid by the churning action of the
pump, prior to its delivery to the filter, giving thereby, its maximum effect of

page_text: precipitation J, K and L, fig 5 are laterally arranged charging hoppers _or
funnels
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 The herein described method of purifying liquid consisting in subjecting the
same to filtration through bed of one grade of material, and subsequently through
another bed of different grade of material, said material being subjected to cross
cleansing currents, substantially as described
2 The method described of discharging and renewing the fouled portion of an up-
current filter-bed, the same consisting in forcing a hydraulic counter current
horizontally through the lower portion thereof and replacing the portion so discharged
by gravitation of the remaining portion, substantially as and for the purposes set
forth
3 A filtering vessel composed of a horizontal cylindric body, and comprising two
separate filter bed containing compartments, said compartments separated by a vertical
partition terminating at its lower portion with an approximately horizontal apron
extending partly across said vessel, beneath one of said compartments, the litter
compartment provided at or near its lower portion with perforated or porous bed
suspending diaphragm, substantially as and for the purposes set forth
4 The herein described filtering vessel embodying two separate filter bed compart-
ments, the one adapted for downward and horizontal filtrate current, the other for
upward filtrate current, each of said compartments hiving inlet and outlet washing
pipes, located at or near their lower section, on opposite sides thereof, adapted to give
a horizontal vashing or cleansing current as and for the purposes set forth
5 In a filtering ipparatus, the combination of two or more filter bed compartments,
the first, or a portion thereof, extending horizontally and terminating at its point of
delivery beneath the second bed or bed, and having a series of washing pipes and a
blow-off pipe or pipes located as described to produce a current through the lower
section of its horizontal portion in a direction common to the filtrate current, whereby
the latter has uninterrupted access to the said second bed or beds for the purposes set
forth
6 In a filtering apparatus the combination of a coarsely pulverized filter bed
containing chamber, adapted to receive a constant filtrate current irrespective of the
herein described intermittent washing current with a finely pulverized filter bed
containing chimber located as shown, to receive the upward filtrate discharge of the
said coarsely pulverized bed, and having washing and blow-off pipes adapted to force
a horizontal current above and adjacent to said diaphragm for the purposes set
forth
7 The combination with a filter bed chamber of the series of herein described
cylindric charging funnels located to impart even distribution of the filtering material
and provided with removable pressure-tight caps as specified
8 The combination with a filter bed chainber of the herein described hltrate
eduction pipe having an extension within suid chamber composed of semi-cylindrical
sections and interposud diaphragm, said diaphragm and one of said sections being
perforated and adapted to receive and ret un a granulate filling for the purposes set
forth
11
1
T
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