Improvements relating to Filter Beds.
Year: 1891

page_text: Date of Application, 13th Oct., 1891-Accepted, 14th Nov., 1891
COMPLETE SPECIFICATION.
Improvements relating to Filter Beds.
I, REGINALD HADDAN of the firm of Herbert & Co. Patent Agents of
18 Buckingham Street Strand W.C. London Civil Engineer do hereby declare the
nature of this invention a communication to me from abroad by George Otto
Rasch of 18 Grosse Reichenstrasse Hamburg Germany Merchant 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 filter beds for purifying water and it consists principally
in constructing the collecting pipes below the filter bed so that the main collecting
pipe is above the subsidiary or branch pipes or channels. The purpose of this
novel arrangement of the main pipe above instead of below the subsidiary pipes is
to do away with the necessity for a deep foundation for the main pipe below the
others and also to obtain the whole depth of the filter bed for filling with sand since
the under layer of gravel formerly necessary to prevent the pipes and mains from
filling with sand is no longer required the amount of gravel being reduced to a
minimum.
The invention is illustrated in the accompanying drawing in which Fig. 1 is a
section in the direction of the axis of the main and Fig. 2 a similar section at right
angles thereto.
A is the collecting main and m the subsidiary collecting channels which may be
of an inverted U shape or of pipe form. The main A is above the channels mand
the latter communicate with the main by branches E on their upper sides projecting
into sockets on the under side of the main.
No special foundation below the filter bed is required for the main A which is
either supported simply by the branches e or by low walls or supports p resting on
the bottom of the filter bed.
As
In place of requiring a comparatively deep layer of gravel under the sand a very
small amount of gravel is required along the entrances of the branch pipes m.
the water rises slowly from the branches m into the main A the sand is not lifted
into the main. The depth of the filter bed may therefore be made less, or more sand
may be placed in it.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is ;-
1. A filter bed in which the main pipe for collecting the filtered water is above
the branch pipes or channels on the floor of the filter, whereby the filtered water
rises from said branch pipes or channels into said main pipe.
2. A filter bed in which a main pipe for collecting the filtered water is in com-
munication along its under side with branches e of branch pipes or channels m lying
below said main on the floor of the filter whereby the filtered water collected
by said branch pipes or channels rises into the main above said pipes or
channels.
3. In a filter bed the combination of a series of branch pipes or channels m,
a small quantity of gravel about the entrances of said pipes or channels, a collecting
main A above said pipes or channels and communicating therewith and supported

page_text: thereon or upon walls or supports and a bed of sand extending to the floor of the
filter the whole substantially as and for the purpose-set forth.
Dated this 13th day of October 1891.