Improvements in the Process of and Apparatus for Softening Waters and Purifying Waste Liquors.
Year: 1894

page_text: Date of Application, 6th Oct., 1894-Accepted, 24th Nov., 1894.
Improvements in the Process of and Apparatus for Softening Waters
and Purifying Waste Liquors..
We, HENRY LEWIS DOULTON, Potter, and ALFRED WILLIAM MANGER,
Engineer, both of Lambeth Potteries, in the County of Surrey, 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:―
Our invention relates to certain improvements in the process of softening waters
and purifying waste liquors, and in apparatus therefor, which may with advantage
be used in connection with apparatus such as is set forth in the Specification of
Letters Patent previously granted to us and numbered 15169, A.D. 1893.
The object of our present improvements is to obtain a clearer and purer saturated
solution of such re-agents as are used for the precipitation of the carbonates in hard
waters, and for the treatment of the various impurities met with in sundry waste
liquors, and to provide for a continuous and automatic and thoroughly efficient
process of softening or purifying.
Our invention comprises chiefly the provision of a quiescent tank, in connection
with the agitating tank for reagents, an improved arrangement of reagent and
settling tanks, of water regulators, and of the final manganous carbon filter, and
other appliances in connection therewith.
These we will fully describe in reference to the accompanying drawing, in
which Fig. 1 is a general plan; Fig. 2 a side elevation partly in section; Fig. 3
illustrates in section the reagent receiving and mixing tank and the quiescent of
clear solution tank connected therewith.
The drawing represents what we term a horizontal arrangement of our apparatus
for use where the ground area is not limited, (though the height may so be,) but it
is to be understood that where ground area is limited and height not so we can
arrange the apparatus in a vertical manner to suit individual circumstances without
departing from the nature of our invention. 'Similar reference letters indicate the
same parts in all the figures.
Our improved process consists in the passing of the saturated solution of lime for
water-carbonates, (or of other reagents for other purposes) from the mixing tank,
in which by mechanical agitation all the useful elements of such reagent are
abstracted, to and through a second tank containing or not as may be required a
screen and filter and thence through interposed regulators and a funnel over a weir
into a second funnel wherein it meets and mingles with a saturatel solution of soda
for water sulphates (or of other reagent for other purposes) flowing from a separate
and automatically controlled tank. The combined product then flows into the main
settling tank and thence by an adjustable outlet into a suitable filter adapted for
variable compression, whence it passes on in a softened or purified condition to
storage tanks or for immediate use.
We have found that water treated with suitable re-agent and passed through
the first mixing and the second or quiescent filtering tank (and prior to the addition
of the soda solution) is eminently fitted for sundry delicate processes, such for
example as the reduction of proof spirits without clouding same.
The apparatus we use for effecting the above process or any part thereof is as
follows:
S is the supply tank fed with water or liquor to be treated, and fitted with ball
cock on the sunnly nine the sunnly nine discharges on to a water wheel of

page_text: source.
any suitable kind mounted in bearings; its spindle w carries a worm or bevel whee
driving a corresponding gear the spindle of which passes down the reagent
mixing tank R; or obviously we may dispense with a supply tank and fix the
wheel W in the top of the reagent tank R and discharge the supply from & direct
upon it. In any case the water wheel drives the mixer M and an Archimedian
screw m, Fig. 3. The former is arranged in the coned base r of the tank R and the
latter in a vertical pipe extension therefrom. The reagent is fed into the tank R
through pipe Afitted preferably with funnel a' containing a screen a². The water
is introduced through valved pipe Pinto pipe r about the screw m which effects
the clearing of the feed pipe and prevents corrosion therein and in the waste pipe
connection H. The reagent may be introduced at the top of tank R and a screen
or sieve a² as shown in Figs. 1 and 3 is provided for restraining all foreign
substances in the reagent. In the tank R the turbid liquor rises up and overflows
down pipe Pl to the lower part of a second cylinder Q which is a quiescent settling
tank in which may be fitted a perforated cone C covered with asbestos sheet, cloth,
flannel, or any material of a fine texture e; through this the solution passes through
overflow pipe p' fitted with cock c to the funnel F of the settling tank B. To the
same funnel we provide in case of shortness of supply a direct connection S³
from the supply tank S which also has an interposed water regulator T¹ and cock c'.
D is a third and separate cylinder for containing a second kind of reagent such as
soda for water; in this tank an agitator (not shown in the drawings) driven by
hand or suitable power is or may be fitted for commingling the soda or reagent
with the water introduced thereto by pipe d from supply tank S or from any other
The soda tank D is connected through pipes d¹, regulator Tand pipe.d
with ball cock d³ and regulator d to a second funnel F', a supplemental ball cock d
being fitted in such manner as to automatically shut off the soda water should the
water level in the settling tank B fall below normal, and thus no waste of soda can
occur. The first reagent solution passes down the funnel as indicated by the
arrows in Fig. 2. and rises in the adjoining separated compartment G overflowing a
"weir" ginto the second funnel F. Herein it meets the soda or second reagent
solution from tank D´ as described and the combined liquid passes down the
funnel F into the lower part of the settling tank B. In this we employ no baffles
or partitions as in our previous Patent before recited because we have found
from experience that deposits of lime are carried forward and are apt to choke the
water ways and clog the filter. From the settling tank B through outlet pipe 0
with stop valve o the so far softened water or purified liquor flows into the filter N
below perforated plate a above which is arranged the manganous carbon J or other
medium. The said outlet pipe O is made telescopic or otherwise adjustable in
height so as to control the volume in the tank before overflow. From the filter N
the softened or purified water flows to its destination through outlet pipe Z. Our
improvements in the filter consist in the addition of an upper perforated plate n²
fitted with a compression screw V working in a cross bearing bar v and fitted with
a hand wheel V by means of which any required degree of pressure can be applied
to the manganous carbon J or other filtering material. We also fix a gauge glass j
by which the water level can always be ascertained by inspection. Also for
thoroughly washing and cleansing the filter when required we provide on one side
the flushing pipes Y Y having a connection m' to the main water supply and fitted
with stop valves y y, and on the opposite side the discharge pipe with valve y¹
and connected to the waste pipe connection H, so that by closing valve o and
admitting pressure from the main at the whole filter can be thoroughly washed
out at any time. Each tank R, Q, D, B, J, is also connected to the said waste
pipe H by connections H fitted with the usual stop cocks as shown. The tanks
are carried by suitable girders, supported in any convenient manner according to
circumstances. Owing to the adoption of the second reagent tank Qwe find that a
much clearer saturated solution can be produced than hitherto and also by constant
circulation therein waste of reagents is prevented, so that the process can be carried
out with less material and cost of maintenance. The arrangement of the water

page_text: regulators too is of importance as producing uniformity of feed independently of
pressure due to head. The new arrangement of the filter improves filtration and
facilitates thorough cleaning which is of essential value.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:-
1. In softening water as above set forth the process of obtaining a clear
Baturated solution which consists in passing the saturated solution of lime (or other
reagent) from the first tank R in which it is agitated and mixed into a second or
quiescent tank Q prior to its passage into the settling tank D, substantially as and
for the purpose set forth.
2. The improved process of softening water or purifying waste liquors as a whole
and effected step by step substantially in the manner and for the respective
purposes above set forth.
3. In the apparatus for effecting the process above referred to or a part of same
the combination with the reagent tank R with water inlet and outlet pipes,
mechanical mixer M, and screw m, and means for introducing the reagent or
reagents, of the quiescent tank with or without the perforated screened filter C,
all substantially as and for the purposes described.
4. The combination of reagent mixing tank R, quiescent tank Q, second reagent
tank D, water regulators T', T", settling tank B without partitions, with
funnels F, F, and weir g, and final filter N, all connected and adapted to operate
substantially in the manner and for the respective purposes above set forth.
5. The arrangement in the filter N of the adjustable compression device
above described, and the means of flushing and cleansing same when required,
substantially as above described and illustrated.
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