Improvements in Apparatus for Softening and Purifying Water.
Year: 1896

page_text: Date of Application, 29th May, 1896-Accepted, 4th July, 1896
COMPLETE SPECIFICATION.
Improvements in Apparatus for Softening and Purifying Water.
I, OSCAR GUTTMANN, of 12 Mark Lane, in the City of London, Civil 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 purification and softening of water, for domestic and industrial purposes, by
chemical treatment, has hitherto been effected by various complicated and costly
apparatus. The object of my present invention is to provide efficient and simple
means for effecting such purification and softening.
The reagent used for softening the water (for example lime water or sodium
carbonate) is either (for instance in using lime water) prepared in a separate
mixing tank (or tanks) and admitted to a feed tank or it is (in the case for example
of sodium carbonate) mixed in the feed tank itself. The feed tank may be any
convenient vessel which is placed above a softening tank of any desired shape and
construction, for instance a galvanized iron tank. In order to regulate the quantity.
of solution of the chemical reagent, and the quantity of water to be treated, various
means can be used, for example both the feed tank and the water inlet to the
softening tank can have simple cocks, or cocks, by means of which a measure of
the quantity can be read off on a dial connected with the plugs of the cocks. Or
an intermediate closed vessel (a Mariotte's vessel for instance) with a tube connected
to the outer air can be provided between the feed tank and the softening tank, in
such a manner, that the distance of the tube from the bottom and thereby the rate
of flow of the reagent can be varied. Or intermediate measuring vessels can be
employed having syphons fixed to them, which rapidly discharge when the liquid
reaches the top level of the syphon. Or an oscillating vessel with two compart-
ments can be used, one of the latter, when full, causing the vessel to tip over,
whereby the other compartment is got ready for filling, and so on alternately.
The water arrives at the bottom of the softening tank together with the chemical
reagent in quantities proportionate to the chemical composition of the water, and
therein they are allowed to react.
If the water has to be used for boiler, or laundry purposes, it can be heated by
either inserting a steam pipe, or preferably by means of a silent water heater, such
as Körting's heater for instance, which without noise, heats the water and thoroughly,
agitates it.
In the case of water for domestic purposes agitation by hand, machinery, or
compressed air, may be employed for promoting the reaction.
Alter the reaction has taken place the water runs into a filter by means of an
overflow pipe, so that a large body of water is constantly kept in the softening
tank, whereby sufficient time for the reaction is given without interrupting the
continuity of the treatment and supply of purified and softened water.
The filter is a long and narrow trough-shaped channel with a horizontal top and
an inclined bottom, so as to give a slow ruu to the water, and may be made of any
suitable material for instance wood, or galvanized iron, and it is divided by partitions
into a number of compartments. The said partitions, at the top and the bottom,
are alternately either perforated or shorter, so that the liquid alternately ascends
and descends from one compartment into the other. The compartments are filled
with wood-wool (fibrous wood-shavings) which is held down by means of perforated
boards, or lattice work, or the equivalent, and can be compressed to any degree by

page_text: weighting the perforated boards, lattice work, or the like. The last compartment
is not filled with wood-wool, but a frame, or frames, covered with cocoa matting,
or cloth, or similar material, is or are vertically placed therein, in order to retain
fine particles of mud or impurity. The overflow from the last compartment is
carried to a storage tank, or pipes carrying the water away can be fixed
immediately on to it. By this filter the water to be filtered alternately descends
and ascends through the wood-wool and the impurities are not only retained by
the wood-wool, but the current being a slow one, the said impurities can settle
down by gravitation, whereby the efficiency of the filter is enormously increased.
Should the efficiency of the filter become impaired by prolonged use the wood-
wool can be taken out from each compartment, without interrupting the working
of the filter and the said wood-wool can be washed in still, or running water, and
put back again into the filter for further service.
The filter can be made in one single channel, or where space is limited several
channels can be arranged, side by side, with the inclination of the bottom alter-
Dately reversed in such a manner, that the overflow of the last compartment of one
filter runs into the first compartment of the next one.
The accompanying drawing illustrates a plant suitable for the softening and
purification of water for boiler and laundry purposes according to my invention.
Figures 1 and 2 are elevations of the apparatus at right angles to each other
and partly in section and Figure 3 is a plan of the filter. A is the feed tank,
a the measuring vessel for the solution of the reagent and provided with a
syphon a, b is the measuring vessel for the impure water provided with a
syphon b, C is the softening tank provided with a silent water heater c and with
an overflow pipe leading to the filter D.
The filter in the example shewn consists of two channels 'D' and D' arranged side
by side having compartments d formed by the partitions which are shorter, or
perforated at d³. The compartments, except the last, are filled with wood-wool,
and this is held down by the lattice covers d'. In the last compartment are
frames d³ covered with cocoa matting, or cloth. The overflow channel E serves
to connect the discharge pipes F.
Having now particularly described and ascertained the nature of my inven
tion and in what manner the same is to be performed I declare that what I
claim is-
1st. In apparatus for the softening and purification of water by chemical
treatment an automatic arrangement for the feeding of the water to be treated
and the chemical reagent into a softening tank and for the filtering of the same
substantially as herein before described.
2nd. A filter for purifying water the said filter consisting of a trough shaped
channel or trough shaped channels having an inclined bottom and divided into
compartments with alternate communications at top and bottom and filled with
wood-wool held down by perforated covers or lattice work or the like the last
compartment having a frame or frames covered with cocoa matting or cloth
substantially as hereinbefore described.
3rd. An apparatus for softening and purifying water consisting of the arrange-
ment and combination of parts substantially as and for the purposes hereinbefore
described and illustrated in the accompanying drawings.
Dated this 29th day of Mar 1896
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.