Improvements in and connected with Filter Plant.
Year: 1899

page_text: Date of Application, 31st Oct., 1899-Accepted, 6th Jan., 1900
COMPLETE SPECIFICATION.
Improvements in and connected with Filter Plant.
We, WILLIAM FRASER STEWART, Mechanical Engineer, and AUGUST HERMAN
KOHLMEYER, Filter Manufacturer, both of 1214, Washington Avenue, St. Louis,
in the State of Missouri, United States of America do hereby declare the nature
of this invention and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement:-
Our invention relates to filters and has for its principal objects to secure the
advantages of high pressure filtration in a filter of the low pressure type.
Another object is to enable one portion of the filter to be cleansed, scraped or
repaired without stopping the regular operation of the other portion.
In the accompanying drawings, which form part of this specification, and
wherein like symbols refer to like parts wherever they occur.
Figure 1, is an end elevation of the filter tank.
Figure 2, is a cross section thereof.
Figure 3, is a side elevation thereof with a portion broken away.
Figure 4, is a horizontal detail section showing the arrangement of filter stones,
and
Figure 5, is a diagrammatic representation of the entire system.
The filtering medium consists of filter stones or tubes 1 arranged in groups or
series in a tank 2 of any kind suitable for a low pressure filter system. Each
group or series of stones has a separate manifold or collecting pipe 3 to which all
the stones in that group are connected, and these collecting pipes 3 extend
through the side of the tank and are all connected to a larger manifold 4 com-
municating with the outlet pipe 5 for filtered water. In each of pipes 6 which
connect the group manifolds or collecting pipes 3 with the general manifold 4
is a valve 7, whereby each group can be cut off from the general manifold.
Each of said connecting pipes 6 also has a faucet 8 threaded for a hose coupling,
said faucet being so located as to communicate with the filter tank whether the
valve 7 is open or closed. Each of said connecting pipes 6 is also fitted with a
valved pipe 9 connected through an intermediate pipe 10 to the outlet pipe 11
of the pump 12, said valved pipe 9 being located between the filter and the
valve 7.
:
The outlet pipe 5 for filtered water is connected to the suction side of a pump 12
through which it communicates with a storage tank 13 to which the service
pipe 14 is connected. The form of pump, which we contemplate using, is an
automatic water motor connected to the supply pipe 15 of the system, and driven
by the pressure of water in said supply pipe. Such motors are well known and
require no special description. As the motor is located in the supply pipe, the
water which drives it passes on to the filter tank. In order to economize water,
the piston of the motor cylinder and the piston of the pump driven thereby, are
preferably, of approximately the same area.
In order to make good the loss of water due to the operation of cleansing and
other causes and to keep the water in the tank up to a predetermined level, a
branch pipe 15 leads from the main supply pipe 15 into the tank and in con-

page_text: trolled by a float valve 16 therein. It is desirable to provide the branch pipe 15ª
with a valve 23 and the branch pipe leading from the main supply pipe to the
pump.v
.with valve 24 as shown. The tank is also provided with an ordinary over-
How pipe 26 for carrying off the excess water.
For the purpose of permitting a general wash of all the stones, the outlet pipe
of the pump is connected to the general manifold by a pipe 27 provided with
any suitable valve 22.
The operation of the foregoing arrangement is as follows. The water enters
the filter tank 2 from any convenient source of supply such as a branch pipe 15"
controlled by a float valve, 16, in said tank. When the valve 24 in the supply
pipe to the water motor is opened the pump in the outlet pipe is set in motion,
and the suction thereof reduces the pressure on the interior of the filter stones
with the same effect as if there was an initial pressure in the tank equal to the
amount of such reduction. Water is thus sucked through the walls of the filter
stones leaving the suspended matter on the outer surface of same. The filtered
water thus drawn through the suction pipe of the pump is forced into, the
storage tank, from which it is drawn as required.
1
During this operation the faucets 8 and valves 21 in the intermediate pipes 10:
between the outlet pipe of the pump and the filter tank remain normally closed.
But in case it is desired to test for a leak, each of the pipes connecting the
group manifolds with the general manifold is successively cut off by manipulating
the valve therein; and then an air pump is applied to the threaded faucet thereof
and the faucet opened. By manipulating the air pump 17 air is forced' back
through the particular group manifold thence into the filter stones. In case any
of said stones are cracked, or any of the joints are leaking, the air will escape
rapidly therethrough and bubble up through the" water and thus indicate the
location of the leak; for the cover of the tank, if it has any, is removed for such
inspection. The faucet is then shut off and the defective stone is unscrewed and
replaced with a new one, merely. by screwing the cap 18 of the new one into
the fitting 19 on the collecting manifold, which may be done without emptying
the tank or interfering with the operation of the other groups of stones. For the
purpose of thus removing and replacing filter stones, each stone is fitted at its
lower end with a metal cap 18 having a hollow threaded stem projecting there-
through; and the group manifolds are provided with threaded sockets or fittings
adapted to receive such stems.
1
In order to cleanse all of the filter stones at once, the valve 22 in the pipe 27
connecting the outlet side of the pump with the general manifold is opened and
the air compressed in the storage tank forces filtered water back through said
manifold and the filter tubes connected thereto. At the same time, the valve
in the waste pipe should be opened to carry off the sediment and muddy water.
In order to cleanse one section of the filter separately, the valve in the water
pipe 27 is closed and at the same time the valve 7 controlling the connection
between one group manifold and the general manifold is closed and the valve 21
controlling the connection between that group manifold and the outlet pipe of the
pump is opened. Then the pump (together with the compressed air in the storage
tank) forces clear water back through the filter stones of that particular group,
while the overflow pipe 26 carries off the excess of water thus forced back into
the tank, without requiring the waste pipe 20 to be opened.
At the same
time, the other groups of stones remain in operation. In the same way, each of
the stones may be brushed or scraped separately without interfering with the
operation of the others because the interior of the tank is accessible during the
operation of filtration.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :
-
1. A filter plant comprising a low pressure filter tank. a filtering medium

page_text: therein arranged in independent sections, a pump in the outlet pipe and means
for reversing the current in each section independently, substantially as described.
2. A filter plant comprising a low pressure filter tank, a filtering medium
therein and a pump connected both on the suction side and on the outlet side to
the outlet pipe for filtered water, and means for controlling such connections,
whereby the current through the filtering medium may be reversed, substantially
as described.
3. A filter plant comprising a low pressure filter tank, groups of filter stones
therein independently connected to the outlet pipe, a pump connected through
intermediate pipes both on its suction side and on its outlet side to the groups
of filter stones, and valves at all of said connections, substantially as described."
4. A filter plant comprising a low pressure filter tank, groups of filter stones
therein independently connected to the outlet pipe, a valve in each of said con-
nections and a faucet between each of said valves and a filter tank adapted to
be coupled to an air pump, substantially as and for the purpose set forth.
5. A filter plant comprising a filter tank, a supply pipe therefor, a water motor
connected to said supply pipe and driven by the water therein, an outlet pipe,
and a pump therein driven by said water motor, substantially as described.
6. A filter plant comprising a filter tank, a supply pipe therefor, an automatic
water motor connected to said supply pipe and driven by the water therein, an
outlet pipe, and a pump therein driven by said water motor, substantially as
described.
7. A filter plant comprising a filter tank, a supply pipe therefor, an automatic
water motor connected to said supply pipe and driven by the water therein, an
outlet pipe, and a pump therein driven by said water motor, the piston of said
motor and the piston of said pump being of approximately the same area, sub-
stantially as described.
Dated this 31st day of October 1899.
For the Applicants,
G. J. LORRAIN, M.I.E.E., M.I. Mech. E.,
Norfolk House, Norfolk Street, London, W.C., Chartered Patent Agent.