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PUUUVUEIETAVUHIE _ PRRUSSUESTLELITT
WATER PURIFICATION
BY LIQUID CHLORINE
FOR SMALL COMMUNITIES
WUE CO EC TTT
SUAS AUNT
ST aT ea a OT a coc
WALLACE & TIERNAN CO., INc.
137 CENTRE STREET, NEW YORK
TECHNICAL PUBLICATION NO. 3
Fourth Edition
1917
DONUT as Se OTTO HT
UU OT VT CO eT I
UTC RE CCC RECT
VEU ll
2900965
WATER PURIFICATION BY
LIQUID CHLORINE FOR
SMALL COMMUNITIES
HERE are three general processes of water
purification: first, sedimentation or storage;
second, filtration; and third, sterilization.
Large impounding reservoirs or settling basins
typify the first process, extensive and elaborate fil-
tration works the second, while the third process is
represented in its highest state of development by
the Wallace & Tiernan chlorine control apparatus.
Some waters require all these processes for proper
purification, some only two. But all water supplies
at times require sterilization in order to make their
potable use entirely safe.
Sedimentation and filtration, when properly oper-
ated, remove color and turbidity and also a large
proportion of the bacteria or germ life. Sterilization
destroys all germ life and is thus a necessary adjunct
to the settling basin or filter. In cases where re-
moval of turbidity or color is not required, steriliza-
tion is the only treatment needed to ensure a safe
water supply.
Practically every source of water is subject to
pollution. The pollution may be continuous or only
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WATER PURI PICATION BY BDO
occasional, but at some timeor other nearly every
water supply is polluted. If the pollution is from
human beings and the germ life entering the water is
not destroyed the consumers are subject to the
potential danger of intestinal diseases such as
typhoid fever or dysentery. The surest, safest, and
cheapest way to destroy this germ life is by the
process of sterilization.
It is generally acknowledged by scientific men
that the most satisfactory method of sterilization is
by the process of chlorination—that is, by adding
to the water to be treated minute quantities of
chlorine or its compounds. The process is a develop-
ment of comparatively recent date, the first recorded
attempt to sterilize water by chlorination in this
country being made in 1906. Since then extension
has been rapid.
The chlorine compound used at first was calcium
hypochlorite or ‘chloride of lime’ but its utilization
was so disagreeable and its uniform application so
difficult that the use of pure chlorine in liquid state
was inaugurated, and the requisite control apparatus
devised.
Some of the specific advantages of liquid chlorine
over chloride of lime may be briefly discussed.
In the first place liquid chlorine is an absolutely
pure chemical. It is usually placed on the market in
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CHLORINE FOR SMALL COMMUNITIES
small cylinders which require very little space for
storing, while chloride of lime is very bulky.
The disagreeable odors and corrosive effects of
chloride of lime are absent in the use of liquid
chlorine, when controlled by efficient apparatus.
Chloride of lime deteriorates rapidly, whereas
liquid chlorine retains its full efficiency indefinitely.
This is one of the greatest advantages to be derived
from the use of liquid chlorine, especially for small
installations.
Under working conditions, due to necessary waste
of bleach, one pound of liquid chlorine is equal in
sterilizing value to eight pounds of chloride of lime.
The sterilization is also more uniform.
Water treated with liquid chlorine is less liable to
taste or odor, due to the more accurate control
possible.
The liquid chlorine apparatus is far more compact
than the installation for chloride of lime.
The liquid chlorine process is applicable under any
conditions and all pressures. It is adapted to remote
control. The gas can be controlled by automatic
feed.
With liquid chlorine the freezing ' difficulties
encountered in the use of chloride of lime are
entirely obviated.
As between the two sterilizing agents, the costs of
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WATER PURIFICATION BY GIieCvis
chemicals are about the same, but the costs of instal-
lation and* operation are greatly in favor of liquid
chlorine.
The application of liquid chlorine to the water to
be purified is, however, ordinarily fraught with
difficulties arising from the very activity of the gas
itself. Though very real, these difficulties are en-
tirely overcome in the design and construction of the
control apparatus manufactured by Wallace &
Tiernan—the only appliances on the market at the
present time adequate to meet all the requirements
of handling chlorine in the liquid or gaseous state for
the purification of water.
MANUAL CONTROL CHLORINATOR
There is set forth in this booklet a description of
the Wallace & Tiernan manual control chlorinator,
solution Feed, Type A, one of the ten types of appa-
ratus manufactured by this company. This type is
particularly suitable for small daily flows of water
and will be of interest to superintendents, chemists,
and managers of waterworks in the smaller munici-
palities.
Messrs. Wallace & Tiernan especially invite con-
sideration, by engineers and others interested in
water purification, of the details of design and the
perfection of mechanical construction.
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SCHLORINE FOR SMALL COMMUNITIES
METHOD AND APPARATUS
Chlorine gas, compressed to liquid state in steel
cylinders holding a hundred pounds, is controlled
and measured by fhe apparatus and introduced into
the water in the proper proportion to effect sterili-
zation.
The extremely small amounts of chlorine required
to destroy the germ life do not alter in the slightest
degree the chemical or physical characteristics of the
water. The germ life is destroyed—otherwise the
water remains the same.
ADVANTAGES IN CONSTRUCTION
There are many advantages in the construction
and design of all Wallace & Tiernan apparatus to
which especial attention is directed.
Simplicity in Design. There are no moving parts
to get out of order or adjustment.
Compactness. Shipment by express is easy and
inexpensive. The apparatus can be sent completely
assembled, ready for operation. Installation is a
matter of hours and minutes—not of weeks and days.
The apparatus may be installed at any convenient
point on the premises and the chlorine piped to point
of application.
Portability. The weight of the apparatus is less
than one hundred pounds.
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WATER PURIFICATION BY. rre
Meters Hydraulic in Principle. All chlorine meters
operate on the hydraulic principle. There are no
moving mechanical parts to cause friction, wear, or
strain. If the meter indicates at all, it indicates
correctly.
Empirical Calibration. The chlorine meter on
every apparatus is empirically calibrated, and then
checked during the efficiency test.
Visibility. All chlorine flow meters and orifices
are entirely visible, making it possible to actually
see at all times that the meter is working perfectly
in every detail, and is clean and free from deposit.
This point cannot be over-emphasized.
Dry Control Parts. All control parts of the appa-
ratus are kept perfectly dry, thus avoiding corro-
sion—for it is only in the presence of moisture that
chlorine is so extremely corrosive.
Constant Drop in Pressure. Each type of appa-
ratus has a differential pressure reducing valve which
maintains a constant drop in pressure across the
chlorine control valve. This produces a constant
flow of chlorine for any setting of the control valve
regardless of varying pressures in the chlorine cylin-
ders or of varying back pressures from the water
being treated. A change in static head in either the
system of chlorine apparatus or water in no way
affects this predetermined drop across the control
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CHLORINE FOR SMALL COMMUNITIES
valve. This drop being about a pound allows a con-
siderable opening of the control valve for compara-
tively low flows of chlorine. Thus, dangers of
stoppage are minimized.
Special Materials. Special metals and materials,
such as platinum, glass, silver, tungsten, and alloys
particularly adapted for chlorine control work are
used where best suited to the needs in question.
Finish. Parts are finished in silver plate and
black enamel.
Interchangeable Parts. The apparatus is built on
the unit system and all parts are perfectly inter-
changeable.
Workmanship. The highest class of workmanship
is employed in making all parts of the apparatus.
Each apparatus, before shipment, is given an actual
chlorine run by experts who have actually installed
and operated chlorine plants on water and sewage
treatment.
Guarantee. All apparatus is guaranteed against
inherent mechanical defects for a period of one year.
LF
WATER PURIFICATION BY 2-203) Th
DESCRIPTION OF APPARATUS
Chlorine gas from the chlorine tank, regulated by
the chlorine control valve, is introduced through the
chlorine check valve and meter into the chlorine
solution jar, and water is at the same time introduced
through the solution jar head. The resulting solu-
tion is piped through the chlorine solution line to
the point of application. When the chlorine solution
is introduced into a suction line under negative head,
a water seal is provided to prevent air being drawn
into the suction line.
The function of the pressure compensator is to
take care of varying pressures in the chlorine tank
and also to maintain a constant drop in pressure
across the chlorine control valve.
CHLORINE FOR SMALL COMMUNITIES
Chlorine Check Valve ~__
Solution Jar Head.
Jet Orifice Cleaner ~
Feed Water Gage - -{
Strainer — —-~
Water Pressure *
Reducing Valvg +-~
Union
Feed Water .
Supply Line’
Feed Water Valve
Solution Jar- ~~
Pulsating Meter
Solution Outlet Tube --—
Water Seal ---~
Water Seal Waste...
Water Seal Line .. =)
Solution Outlet Bracket. |
Solution Line-~-.._.
Tank Valve—.
Valve Yoke ~~...
Chlorine Tank
7 -+-Hi Tank Pressure Gage
orine Control Valve
ompensator Cap
+ fi Pressure
Compensator
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Flexible Tank
Connection
/_- Auxiliary Tank Valve
WATER PURIFICATION BY LIQUID
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CHLORINE FOR SMALL COMMUNITIES
In the treatment of watera chlorine flow meter, to
be reliable, must give a constant rate—not per day,
nor per hour, nor per minute—but even less than
per second, for the obvious reason that the water is
flowing constantly and must receive its chlorine con-
stantly and not intermittently.
The chlorine solution jar and pulsating meter
are made of special annealed glass. They are con-
sequently absolutely unattacked by the chlorine
solution. Furthermore, the flow of chlorine can be
actually seen no matter how small. A flow of one
pound of chlorine per twenty-four hours (which
amount will treat 300,000 gals. of water) is a flow
of .000694 Ibs. per minute or .oooo115 lbs. per second.
This quantity is entirely too minute to measure by
any method but a volumetric one.
The type meter used will indicate accurately from
1/10 lb. of chlorine per 24 hours (.00000115 lbs. per
second) up to 12 lbs.
One pulsation of the meter gives 100 milligrams or
1/4534 lbs. (.00022 Ibs.). By simply timing the num-
ber of pulsations per minute, and using the chart of
operation furnished with the apparatus, the desired
flow of chlorine can be easily and accurately set.
The operation of this meter is fully described and
illustrated on pages 12-13.
A small meter operating on the same general
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WATERR PURIFICATION 2 Y4L10 37D
principle which will indicate accurately flows as low
as 1/100 lb. chlorine per 24 hours (.o00000115 |b.
per second) can be furnished on request, thus making
the apparatus suitable for the smallest water sup-
plies.
A ready solubility of chlorine is secured by the
action of a water jet which thoroughly churns upthe
chlorine and water in the jar.
DESCRIPTION. OF PULSATING METER
The meter A in the chlorine absorption chamber
is shown in detail and principle in the drawing on
the opposite page. View X shows the water level
2 in the meter at the beginning of the pulsation, and
view Y shows the water level 2 just before the siphon
C-G breaks at D, which completes one pulsation of
the meter.
Its operation is as follows. When the downward
flowing gas in A reaches the point D, it will rush up
through the tube G of the siphon, and the bell or
compartment B will refill with water up to the upper
end of C. This completes one pulsation or measure
of the meter, and the amount of gas delivered by
this one pulsation is, of course, the capacity of the
compartment B between the points F and D.
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CELORINE FOR SMALL COMMUNITIES
This is a volumetric
meter, hydraulic in
principle, and if it op-
eratesat all it must
. operate correctly. Its
reading is accurate
from a minimum of
1/10 lb. toa maximum
of 12 lbs. per 24 hours.
All the openings are
large so that there is
no danger of stoppage.
All parts are of glass,
which is in no way
affected by the chlor-
ine solution. Further-
more, this plan of con-
struction enables the
attendant to actually see the chlorine flowing, no
matter how small the amount. This point is essen-
tial in reliable chlorine control work.
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WATER PWRLFIGATION BY LPO cre
COST .OF QGPERATION
It has been our experience, with nearly one
thousand installations of our apparatus in cities and
towns in the United States, Cuba, Canada, and
Mexico, that with a water low in turbidity and color
a dose of 2/10 parts of chlorine per million is ample to
secure satisfactory destruction of germ life. This
dose is equivalent to 1.66 lb. chlorine per million
gallons of water treated.
A fair average pre-war figure for the price of liquid
chlorine throughout the United States, under nor-
mal conditions, is tex cents per pound on the job.
On this basis, it is evident that with a water low in
turbidity and color the germ life can be destroyed for
less than 17 cents a million gallons. Surely this is a
good investment for any community and offers the
cheapest and surest form of insurance against all
danger of water-borne disease epidemics.
In cases where the water to be treated has a high
turbidity or color, the amount of chlorine required is
somewhat higher, but it is very rarely that the cost
of treatment exceeds 45 or 50 cents per million
gallons.
There is no labor charge involved in operating the
apparatus other than that of removing an empty
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CHLORINE FOR SMALL COMMUNITIES
chlorine cylinder and attaching a full cylinder. As
this work can be done in two or three minutes and is
necessary only at rare intervals the cost is so slight
as to be negligible.
The apparatus described can be erected by any
capable mechanic without difficulty in one or two
hours. The apparatus with necessary connections is
shipped complete, and full directions for installation
and operation accompany shipment.
If you are interested in making the water supply
of your community absolutely safe, we will gladly
quote you prices on this apparatus upon receipt of
detailed information concerning your conditions.
The data can conveniently be given on the accom-
panying blank.
Upon request we will gladly send our complete
treatise, Chlorine Control Apparatus for Water and
Sewage Purification.
WALLACE & TIERNAN CO., INC.,
137 CENTRE STREET NEW YORK
DOUGLAS C. MCMURTRIE NEW YORK