U.S. patent number 3,870,471 [Application Number 05/437,077] was granted by the patent office on 1975-03-11 for dissolving apparatus.
This patent grant is currently assigned to Olin Corporation. Invention is credited to Arlon G. Sangster, Joseph J. Tepas, Jr..
United States Patent |
3,870,471 |
Tepas, Jr. , et al. |
March 11, 1975 |
DISSOLVING APPARATUS
Abstract
An improved apparatus for dissolving and dispensing soluble
material including a container having an upper and a lower chamber.
The upper chamber is separated into a first and a second
compartment. A rotary receptacle in the first compartment receives
liquid through an inlet in the first compartment and is
periodically emptied, releasing precisely the same amount of liquid
each cycle. The second compartment contains a magazine which holds
soluble solids to be dissolved by the liquid. A control valve
regulates the amount of liquid contact with the solid. The lower
chamber receives the solution from the second compartment and thru
valve means releases the solution into the liquid system to be
treated. The improvement comprises providing means for vertically
adjusting the magazine to control the dissolving of soluble solids.
The novel vertical adjustment means is comprised of a bracket
attached to a wall of the magazine, a cam engaging the bracket and
a wheel engaging the cam. The configuration of the cam is a
continuous non-circular curve of from 0.degree. to about
340.degree.. The cam allows a wide range of solution concentrations
to be produced by controlling the amount of contact between the
liquid and the soluble solid in the magazine.
Inventors: |
Tepas, Jr.; Joseph J. (Easton,
CT), Sangster; Arlon G. (Sterling, MA) |
Assignee: |
Olin Corporation (New Haven,
CT)
|
Family
ID: |
27014543 |
Appl.
No.: |
05/437,077 |
Filed: |
January 28, 1974 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
394007 |
Sep 4, 1973 |
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Current U.S.
Class: |
422/106;
210/167.11; 137/268; 222/71; 248/157; 422/264; 239/310 |
Current CPC
Class: |
B01F
1/0033 (20130101); E04H 4/1281 (20130101); B01F
15/045 (20130101); C02F 2103/42 (20130101); Y10T
137/4891 (20150401) |
Current International
Class: |
B01F
15/04 (20060101); B01F 1/00 (20060101); E04H
4/00 (20060101); E04H 4/12 (20060101); B01d
011/02 (); B01f 001/00 () |
Field of
Search: |
;23/267E,272.7,272.8
;248/161,157,186 ;239/310 ;210/169,167 ;222/71 ;137/268 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Monacell; A. Louis
Assistant Examiner: Emery; S. J.
Attorney, Agent or Firm: Clements; Donald F. O'Day; Thomas
P. Haglind; James B.
Parent Case Text
This is a continuation-in-part of co-pending application Ser. No.
394,007, filed Sept. 4, 1973.
Claims
What is claimed is:
1. In an apparatus for dissolving and dispensing soluble solid
material including in combination a closed container having an
upper chamber and a lower chamber and at least one partition
separating said chambers, said upper chamber having a first and a
second compartment separated by a divider; an inlet for liquid in
the upper part of said first compartment, a rotary receptacle in
said first compartment and attachment means therefore comprising a
pair of trunnions, said receptacle receiving said liquid from said
inlet and upon rotation periodically emptying said receptacle;
first flow control means associated with at least one opening for
controlling liquid flow between said first compartment and said
second compartment; a magazine in said second compartment to hold
soluble solids, said magazine having a pervious lower end
permitting said liquid to contact the lower portion of said solids,
at least one opening for liquid flow between said second
compartment and said lower chamber, an outlet in said lower chamber
and second flow control means for liquid flow through said outlet,
the improvement which comprises said magazine having vertical
adjustment means comprising:
a. a bracket attached to and spaced apart from a wall of said
magazine,
b. a an eccentric cam having the configuration of a continuous
curve housed in said bracket,
c. a rotary member engaging said cam,
d. said cam frictionally engaging said bracket on said wall of said
magazine and upon rotation of said rotary member to control said
dissolving of said soluble solids by adjusting the height of said
magazine in contact with said liquid.
2. The apparatus of claim 1 in which said cam has the configuration
of a continuous curve of from 0.degree. to about 340.degree..
3. The apparatus of claim 1 in which said first flow control means
is a cup having a lip of sufficient diameter to encompass said
openings in said first and said second compartment.
4. The apparatus of claim 1 in which said receptacle is a tear drop
shaped vessel haaving at least one opening therein.
5. The apparatus of claim 4 in which said partition separating said
upper and said lower chambers comprises an inclined section, a
substantially vertical section and a substantially horizontal
section.
6. The apparatus of claim 5 in which said opening between said
second compartment and said lower chamber is comprised of a drain
having a liquid retaining dam.
7. The apparatus of claim 6 in which said second flow control means
for controlling said outlet is a float valve.
8. The apparatus of claim 7 in which said magazine is removable
from said compartment.
9. The apparatus of claim 7 in which said pervious end of said
magazine is a grid.
10. The apparatus of claim 8 in which said magazine has a cover
comprising a plate having at least one opening, a handle having at
least two grips, two latching means for securing said cover to said
magazine, one of said latching means being attached to said grips
and passing thru said opening, and only one of said grips having
releasing means to release said latching means from said
magazine.
11. The apparatus of claim 10 in which said handle is attached to
said plate by said latching means.
12. The apparatus of claim 7 in which said inlet has control means
comprising a flow indicator tube attached to valve means.
13. The apparatus of claim 12 in which said magazine is filled with
soluble solids selected from the group consisting of calcium
hypochlorite, dichlorocyanuric acid and alkaline salts thereof,
trichlorocyanuric acid and akaline salts thereof,
tetrachloroglycoluril, 1,3-dichloro-5,5-dimethylhydantoin, and
1-chloro-3-bromo-5,5-dimethylhydantoin.
14. The apparatus of claim 13 in which said soluble solid is
calcium hypochlorite.
15. The apparatus of claim 7 in which said magazine is tapered, the
cross sectional area at the top being slightly smaller than the
cross sectional area at the pervious end.
Description
This invention relates to apparatus for the preparation and
controlled feeding of aqueous solutions of solid particulate
material. More particularly, the apparatus provides means for
preparing aqueous solutions of water-soluble solids and dispensing
said solutions at controlled rates. Still more particularly, this
invention relates to apparatus for supplying solutions containing
available chlorine over a wide range of concentrations from solid
hypochlorite compositions in conveniently handled granular, pressed
or tabletted forms at accurately controlled rates for use in a
variety of chlorination and water treating applications differing
widely in the concentration of the solution required.
In the treatment of water including particularly swimming pools, a
supply of aqueous solution of an available halogen compound,
preferably a hypochlorite, is commonly metered into a flowing body
of the liquid to be treated. Sodium hypochlorite solutions are
available commercially at concentrations not exceeding 15 percent
of available chlorine but such solutions deteriorate rapidly during
shipment and storage. Solid sodium hypochlorite compositions are
not available because they are very unstable. Calcium hypochlorite,
on the other hand, can be shipped as a relatively stable solid
containing up to about 85 percent or more of available chlorine and
can be stored for long periods without appreciable loss of
available chlorine.
In spite of the advantages of solid calcium hypochlorite over other
sources of available halogen for use as a sterilizing agent, there
is a problem in applying the solid continuously and directly to
water in such a manner that only a few parts per million of
available chlorine are ultimately present in the water. In
conventional methods of application in swimming pools, granular
calcium hypochlorite is sometimes added directly to the water in
the pool or tablets are placed in the skimmer or in dissolving
baskets around the pool. Preferably, however, solid calcium
hypochlorite is dissolved in water to form a solution of desired
concentration which is metered into the water in the circulating
system at a rate to maintain residual chlorine concentration
generally from about 0.3 to about 1.5 parts per million in the
pool.
Many devices have been devised to control dissolution of soluble
materials but which are not satisfactory for use with calcium
hypochlorite or other substances having similar solubility and
solution characteristics.
U.S. Pat. No. 1,216,051 shows a dispensing device having a
solute-containing magazine covered at one end by a perforated disk
and supported at a fixed elevation in the total stream of flowing
water to be treated. The flow of the total stream promotes
turbulence in the region of the perforated end of the magazine and
extensive wetting of undissolved solute. Contact between solute and
liquid and hence the degree of liquid treatment is dependent on
liquid pressure.
U.S. Pat. No. 2,971,825 shows a dispenser for dissolving and
dispensing solutes by passing a variably controlled portion of the
inflowing fluid into and out of a mixing chamber which contains the
solute and which is partially covered by a screen. Turbulent flow
in the region of the perforated end and extensive wetting and
mixing of solvent and undissolved solute are encouraged by the
structure of the device of this patent. The range of concentrations
for treated solutions is limited by the extent stream deflection is
permitted by the controls. The uniformity of concentrations of
treated solutions is dependent on liquid pressure.
The dispensing device of U.S. Pat. No. 3,107,156 comprises a solute
containing magazine suspended into a container into which a
constant flow of water enters. The magazine has a water soluble
plastic film at the lower end which dissolves in contact with water
and exposes the solute to the dissolving action of water. The
extent of contact of solute with water is adjusted by raising or
lowering the magazine. A siphon tube determines the upper and lower
liquid levels in the container and periodically releases a quantity
of treated water.
In contrast to the above dispensers, a recently developed
dispensing apparatus provides for accurately controlled
concentrations of treated solutions which are substantially
independent of changes in the pressure conditions in the system
being treated. The dispenser provides controlled tubulence in the
area of liquid-solute contact and prevents undesired contact
between the liquid and the soluble material. Continuous immersion
of the soluble material in the liquid is avoided by the dispensing
apparatus. Periodic release of a controlled quantity of liquid from
the receptacle permits liquid-solute contact which is essentially
unaffected by changes in liquid flow rates. The dispensing
apparatus permits a zero feed rate of soluble material while
maintaining a continuous flow of liquid through the apparatus under
normal operating conditions.
This recently developed dispenser, disclosed in U.S. application
Ser. No. 368,899, filed June 11, 1973, by Joseph J. Tepas, Jr.,
includes a closed container having an upper chamber and a lower
chamber and at least one partition separating the two chambers. The
upper chamber is separated into a first and a second compartment by
a divider. The first compartment contains an inlet for liquid in
its upper part and a rotary receptacle for receiving the liquid
from the inlet. When filled, the receptacle rotates and discharges
the liquid and returns to its original position to receive
additional liquid. A channel in the divider between the first and
second compartments permits the liquid to flow into the second
compartment, the flow being regulated by a valve. A magazine in the
second compartment for holding soluble solid materials has a grid
at the lower end. Liquid flowing into the second compartment, rises
up thru the grid and contacts of soluble solid, forming a solution.
The concentration of the solution is controlled by the valve
setting regulating liquid flow rate. The solution formed passes
thru an opening between the second compartment and the lower
chamber. A valve in the lower chamber regulates the flow of
solution from the dispenser to the body of liquid to be
treated.
U.S. application Ser. No. 394,007, filed Sept. 4, 1973, by the
present Applicants, discloses an improved means to control liquid
flow from the first compartment to the second or dissolving
compartment. This flow control means is a rotary member having a
cup and an aperture permitting a variable portion of the liquid
from the rotary receptacle to pass directly to the lower chamber
without passing thru the dissolving compartment.
When a highly concentrated solution is to be dispensed, a large
portion of the liquid contacts the soluble solid. When dispensing a
solution of low concentration, a small portion of the liquid
contacts the soluble solid. This small portion, however, must
dissolve sufficient solid to form a relatively concentrated
solution in the dissolving compartment. This concentrated solution
is then diluted to the desired concentration in the lower chamber
and dispensed to the body of liquid to be treated. Improved
operation is attained by allowing a large portion or all of the
dissolving liquid to pass thru the dissolving compartment to
provide better mixing in the dissolving compartment.
It is desirable therefore to provide a dispensing apparatus which
permits a large portion or all of the liquid to pass thru the
dissolving compartment while maintaining the concentration of the
solution dispensed at the desired level.
It is an object of the present invention to provide a novel control
means for providing a less concentrated solution in the dissolving
compartment while maintaining the desired concentration of solution
dispensed.
An additional object of the invention is an improved cover for the
dispenser magazine.
It is another object of this invention to provide an improved
apparatus for dissolving solid material to form a solution and
dispensing the resulting solution into a liquid to be treated.
A further object of the invention is to provide an improved
apparatus for feeding active chlorine solutions to swimming pool
water.
These and other objects of the invention will be apparent from the
following detailed description of the invention.
It has now been discovered that the foregoing objects are
accomplished in a novel control means which vertically adjusts the
magazine to control the dissolving of the soluble solid. In a
preferred embodiment of the invention the control means comprises a
bracket attached to said magazine, a cam engaging the bracket, and
a rotary member engaging the cam.
This novel control mens is especially useful in an apparatus for
dissolving and dispensing soluble material to form an improved
novel dispensing apparatus which includes in combination a closed
container having an upper chamber and a lower chamber and at least
one partition separating the chambers. The upper chamber is
separated into a first and a second compartment by a divider. An
inlet in the upper part of the first compartment introduces liquid
from an external source into a rotary receptacle housed in the
first compartment. The receptacle is located below the inlet and is
attached to the sidewalls of the first compartment by a pair of
trunnions. Means are provided for periodically emptying liquid from
the receptacle. Liquid flow is regulated by a first flow control
means associated with at least one opening for controlling liquid
flow between the first compartment and the second compartment. A
magazine in the second compartment for holding soluble solids has a
pervious lower end permitting liquid from the receptacle to contact
the solids. At least one opening is provided in the second
compartment permitting liquid to flow between the second
compartment and the lower chamber. An outlet in the lower chamber
is equipped with a second flow control means which permits the
regulation of liquid flow thru the outlet.
FIGS. 1-5 show various embodiments of the novel dispenser of this
invention. Corresponding parts have the same identifying numbers in
FIGS. 1-5. FIG. 6 shows a diagram utilizing the dispenser of this
invention in a swimming pool installation.
FIG. 1 is a partial vertical cross section of one embodiment of the
apparatus of the present invention.
FIG. 2 is a front view of the embodiment of FIG. 1.
FIG. 3 is a front view of one embodiment of the cam employed in
FIGS. 1 and 2.
FIG. 4 is a side view of one embodiment of the cover of the
magazine employed in FIG. 1.
FIG. 5 is a top view of the embodiment of FIG. 4.
FIG. 6 is a diagrammatic plan of a swimming pool filtering system
incorporating the dispensing apparatus of the present
invention.
The dispensing apparatus of this invention, as shown in FIG. 1, is
divided into upper chamber 1 and lower chamber 2 by partition 3.
Upper chamber 1 is separated into first compartment 4 and second
compartment 5 by divider 6. Liquid from an external source enters
the apparatus by way of tube 7 passing thru flow indicator 8 and
inflow valve 9 into inlet 10 attached to the upper part of wall 14
of first compartment 4 and below cover 61. Deflector 70 is inserted
at the discharge end of inlet 10 to deflect the liquid into rotary
receptacle 11, which is attached to the side walls of first
compartment 4 by means of a pair of trunnions 12. Receptacle 11
empties itself when the liquid volume reaches a predetermined level
by pivoting on trunnions 12 stopping when the front edge of
receptacle 11 contacts protuberance 71. Baffle 48 reduces splashing
when liquid is released from receptacle 11.
Upon emptying, receptacle 11 returns to its original position,
stopping when protuberance 72 on receptacle 11 contacts the edge of
opening 73. Opening 73 allows liquid to flow directly between first
compartment 4 and lower chamber 2 in the event of a build-up of
liquid in first compartment 4. Liquid from receptacle 11 flows down
partition 3 thru opening 74 in partition 3. Cup 76, attached to
partition 3, directs the flow of liquid from first compartment 4
down through opening 74 into cup 76 and from cup 76 up thru opening
79 in partition 3, the liquid passing thru channel 80 and into
second compartment 5.
Magazine 18 is housed in second compartment 5 having removable
cover 60. Magazine 18 has a lower pervious end comprising grid 19
which supports a liquid soluble particulate material (not
shown).
Yoke 30 is attached to wall 31 of magazine 18. Dial 32 is engaged
by cam 33 thru opening 35 in wall 34 of compartment 5. Cam 33
engages yoke 30 thru an opening (not shown) in the plate 36 of yoke
30. The rotation of dial 32 turns cam 33 which moves yoke 30 and
thus magazine 18 vertically. Soluble solid particulate materials
are introduced into magazine 18 thru removable cover 38. Dial
control settings (not shown) are indicated along the circumference
of dial 32. From second compartment 5 the solution formed passes
down thru drain 21 into lower chamber 2.
FIG. 2 illustrates a frontal view of the novel vertical adjustment
means of FIG. 1. Yoke 30 is comprised of plate 36 attached to and
spaced apart from wall 31. Cam 33 is inserted between wall 31 and
plate 36. Cam 33 engages dial 32 thru opening 37 in plate 36 and
opening 35 (not shown) in wall 34 of compartment 5.
FIG. 3 represents one embodiment of cam 33 employed in the present
invention.
FIGS. 4 and 5 depict a side view and front view respectively of an
embodiment of cover 38 of magazine 18. Cover plate 39, having
opening 40 and 42 at each end and opening 41 at the center, rests
on the top of magazine 18. Handle 43 has grips 44, 45 and 46 and
latches 47, 48 and 49, respectively. Latch 47, attached to grip 44,
is inserted thru opening 40 and secured to a wall of magazine 18.
Latch 48 is attached to grip 45 and is inserted thru opening 42 and
secured to cover plate 39. Latch 49 is attached to grip 46 and
inserted thru opening 42 and is secured to a wall of magazine 18.
Of the three grips, only grip 46 has sufficient flexibility to bend
enough to release latch 49 and permit latch 47 to be released and
inner cover 38 to be removed. A lifting force applied to either of
grips 44 or 45 will not remove inner cover 38 but will instead
remove magazine 18 from compartment 5.
FIG. 6 illustrates the use of the present invention in supplying
chlorinated water to a swimming pool system including swimming pool
50, a pump 51 with its low pressure or suction side connected by
conduit 52 to pool 50 and with its high pressure or outlet side by
conduit 53 to filter 54. A portion of the water discharged from
filter 54 through conduit 55 passes through conduit 56 into
dispenser apparatus 57. For example, when magazine 18 of the
dispenser of this invention contains calcium hypochlorite and pool
water is contacted with the calcium hypochlorite contained therein,
the resulting chlorine-containing solution formed by dispenser
apparatus 57 is discharged through outlet 24 (not shown) to conduit
58 to pump 51, through conduit 53 to filter 54 and through conduit
55 to pool 50.
The dispensing apparatus of this invention is suitable fabricated
of metal or plastic depending on the solute and liquid with with it
is to be used. When solid hypochlorites, for example, calcium
hypochlorite, or solutions of hypochlorites are employed, the
materials of construction are preferably those resistant to its
action. Particularly suitable for this purpose are a considerable
number of plastic compositions, for example, Lucite which has the
additional advantage of transparency. The apparatus may also be
constructed of other resins, for example,
acrylonitrile-butadiene-styrene, Bakelite, nylon, polyethylene,
polyvinyl chloride, and polystyrene and of suitable metals
including copper, brass, stainless steels, and titanium.
The dispensing apparatus is designed to operate with liquid
supplied at suitable pressures and may be operated without
controlling means for liquid flow rates. In systems with highly
variable liquid flow rates, it may be desirable, however, to equip
the inlet with means to regulate liquid flow. In the case of
treating swimming pool water, for example, control means combining
a visual flow indicator and a valve member are useful in indicating
a pressure build-up in the filter or at the hair and lint screen
and to provide visible check valve function when the filter pump
stops. An example of a suitable inlet liquid flow control means is
a combination of a ball flow indicator and a tee valve.
The receptacle for the liquid is self-emptying and provides for the
release of liquid on a periodic basis, controlled, for example, by
a predetermined volume or weight of liquid. It can, for example, be
shaped generally cylindrical, ellipsoidal or circular, having at
least one opening for liquid to enter and be discharged. In one
embodiment, a tear drop shaped receptacle is attached to the walls
of the container, for example, by a pair of trunnions or pivot pins
and is carefully balanced so that upon emptying the liquid it
returns by gravity to its original position. A stopping mans for
maintaining the receptacle at a suitable position for filling may
be provided by the appropriate length of the inlet tube or by
appropriately located protuberance as shown in FIG. 1.
One or more openings can be provided in the first compartment to
permit flow of liquid directly to the lower chamber. A suitable
example is an opening or overflow tube which prevents the build-up
of liquid in the first compartment.
The novel vertical adjustment apparatus for controlling the height
of the tabled magazine permits a wide range of solution
concentrations to be dispensed. The cam may have any suitable
configuration which permits the desired change in the height of the
magazine in the dissolving compartment. It is preferred that the
configuration of the cam permit change in the height of the
magazine over any selected distance. In one embodiment the
configuration of the cam is a non-circular continuous curve
increasing in slope from 0.degree. to about 340.degree.. Its design
therefore permits a continuous altering of the magazine height and
thus the amount of contact with the soluble solid. The
concentration of the solution to be dispensed can be varied by any
degree and is not limited to specific intervals of change. The
bracket attached to the magazine may be of any design which
provides suitable means of engagement with the cam. In one
embodiment, the bracket is a yoke which houses the cam and
frictionally engages the cam along a face of a plate of the yoke.
It will be readily understood that the vertical adjustment of the
magazine cam also be made by any engagement of the cam with a wall
of the magazine.
The novel vertical adjustment apparatus of the present invention
can be used in combination with the first flow control means of
U.S. application Ser. Nos. 368,899 and 394,007. Where this is done,
it is preferred that the first flow control means permit a large
volume of liquid to flow into the second compartment. In a
preferred embodiment, the first flow control means is a
nonrotatable cup permitting all of the liquid to flow into the
second compartment.
By permitting a large portion or all of the liquid to flow from the
first compartment thru the second or dissolving compartment, the
desired concentration of solution is obtained while providing for
adequate mixing. The concentration of solution formed in the
dissolving compartment does not need to be inordinately high as the
concentration of the solution in the lower chamber of the dispenser
is close to or the same as that formed in the dissolving
compartment.
The supply magazine has the form, for example, of a hollow
rectangular or cylindrical solid having a pervious lower end. The
magazine is insertable into the second compartment of the upper
chamber and stop means are provided to establish the level of the
pervious lower end of the magazine at an appropriate distance above
the bottom of the compartment. The pervious lower end can be, for
example, a grid of suitable mesh attached to the magazine and made
integral therewith. The magazine can be removable from or made
integral with the second compartment.
In a preferred embodiment, the magazine is tapered, the cross
sectional area at the top being slightly smaller than the cross
sectional area at the bottom, or pervious end. Such tapering is
particularly desirable when tabletted materials are employed in the
magazine. The tapering enhances the downward movement of unwetted
tablets to replace wetted tablets being dissolved by the liquid and
prevents bridging of the tablets when they are first contacted by
the liquid.
The novel removable cover permits the magazine to be filled with
soluble material in a form which is suitable for dissolving in the
liquid being supplied to the apparatus of the invention. Its
construction however prevents the cover from being readily removed
and access gained to the soluble solid, for example, by young
children. While a magazine is a preferred emobodiment for
containing the soluble solids it will be recognized that other
supports or holders having suitable openings for liquid may be
used.
The novel cover of the magazine is comprised of a plate which
contacts the magazine and a handle. The handle has at least two
grips for grasping the cover. At least one of these grips has
latching means attached. Where the plate is separate from the
handle, the plate has at least two openings to permit entry of at
least two latching means to secure the cover to the magazine, for
example, by attaching to the walls of the magazine. If desired, the
plate may be attached to the handle, for example, by the same
latching means used to attach the handle to the magazine. Where
this is the case, one of the latching means may be directly
attached to the plate and the other to a grip on the handle. Of the
grips on the handle, only one is able to release a latching means
and permit the cover to be removed. In a preferred embodiment, one
of the grips has sufficient flexibility to flex or bend when raised
to release the latching means and permit the handle to be moved
releasing any other latching means and free the cover from the
magazine.
The lower portion of the magazine is periodically submerged in
liquid, with the volume of the submerged portion usually being no
greater than about 5 percent of the total volume of the magazine.
The extent of contact is regulated by the magazine's vertical
adjustment means.
The vertical adjustment apparatus of the present invention is able
to vary the height of the magazine's grid above the partition
separating the second compartment from the lower chamber. The grids
height can be adjusted over any suitable range. The desired grid
height being determined by the nature of the soluble solid
employed, the liquid used as the solvent, and the size of the
apparatus.
As soluble material dissolves at the pervious end of the magazine
and is removed, the soluble material originally in the air space
above and not wetted by liquid, gradually descends to the pervious
end to replace that dissolved. Only soluble material about to be
dissolved is contacted by liquid flowing across the pervious end of
the magazine.
At least one opening, is provided to permit the flow of solution
between the second compartment and the lower chamber. This may
comprise, for example, a drain with a suitable dam to maintain
liquid level nearr the grid at its lowest position. In addition,
drain means suitably notched to minimize plugging by non-dissolved
particles can be employed. If desired, drain means with a variable
size orifice can be advantageously used especially where
particulate materials of differing degrees of solubility are
employed with a common solvent.
Release of solution from the lower chamber through outlet 24 to the
liquid to be treated is controlled by a second flow control means,
a float valve, for example, so arranged that air is prevented from
being drawn into the pump suction line causing undesired
introduction of air into the recirculating system.
The dispenser is designed to operate with liquid supplied at
suitable pressure and to discharge the solution at or below
atmospheric pressure into the liquid to be treated.
The rotary receptacle accumulates a volume of liquid and
periodically instantaneously releases this liquid to a dissolving
zone wherein the liquid contacts a soluble material in the lower
end of the magazine to form a solution containing a carefully
controlled amount of the soluble material. By releasing precisely
the same amount of liquid during each cycle, accurately controlled
solution concentrations are consistently obtained for a particular
setting of the dial control. A wide range of concentrations are
provided by the apparatus of this invention. For example, when
dissolving solid calcium hypochlorite, available chlorine in
amounts of from 0 to greater than about 4,000 grams per day can be
supplied. In contrast, most currently available erosion type
dispensing devices for chlorinating swimming pools cannot provide a
zero feed rate of available chlorine while operating, nor can they
feed more than approximately 300 grams of available chlorine per
day when dissolving the prescribed available chlorine-containing
compound.
The device of the present invention is used particularly
advantageously when it is desired to dispense solutions of soluble
solid materials supplied in a suitable form at accurately
controlled rates. These rates are varied by controlling the volume
of liquid in contact with the soluble material. The dispenser of
this invention is particularly useful in the application of solid
hypochlorites, for example, calcium hypochlorite, to bodies of
water, for example, in treating water in swimming pools, water
plants in small municipalities, bottling plants, dairies and
cooling systems where the addition of a sterilizing agent or other
chemical is desirable. The device also can be advantageously used
in the treatment of industrial wastes to destroy color, odor and
toxic constituents, and for odor and bacterial control in sewage
effluents. Pressed tablets of calcium hypochlorite are especially
suitable in the present apparatus, but granular shapes and sizes of
particles are also suitable. The apparatus can be used for
dissolving and feeding other chemcials, for example, sodium
fluoride in minor amounts for water supplies, polyphosphates and
compositions containing them for water softening, soda ash
furnished as briquettes or fused soda ash for adjusting the
alkalinity of aqueous bodies, sodium chloride, alum and available
chlorine compounds other than hypochlorite include, for example,
dichlorocyanuric acid and alkaline salts thereof, trichlorocyanuric
acid and alkaline salts thereof, tetrachloroglycoluril,
1,2-dichloro-5,5-dimethylhydantoin and
1-chloro-3-bromo-5,3-dimethylhydantoin.
The following examples are presented to illustrate the invention
more fully. All parts and percentages are by weight unless
otherwise specified.
EXAMPLE I
A dispensing apparatus, substantially as shwon in FIGS. 1, 2 and 3,
was fabricated substantially of acrylo nitrile-butadiene-styrene
resin. Tear drop shaped receptacle 11 had a capacity of
approximately one quart of liquid. Magazine 18 had a grid forming
the previous end and was filled with calcium hypochlorite
briquettes containing 70 percent Ca(OCl).sub.2. Magazine height
control wheel 32, which controls the amount of contact between the
liquid entering the second compartment and the soluble solid on
grid 19, was set at 2. At this setting, the grid was at a height of
about 1.8 inches above the partition forming the bottom of the
second compartment.
The dispensing apparatus was connected to a test stand simulating a
swimming pool installation to test uniformity in maintaining
available chlorine levels.
The test stand included a stirred tank having a capacitty of 150
gallons of water.
Fresh water at a temperature of 85.degree.F. was added to the
dispensing apparatus at the rate of 15 gallons per hour.
At a control setting of 2, the dispensing apparatus was operated
for a period of 3.25 hours. Analyses of the treated solution, taken
at intervals of 1, 2 and 3.25 hours after starting liquid flow to
the dispensing apparatus, showed an average available chlorine
concentration of 71 parts per million, with the highest reading
being 75 parts per million and the lowest reading 67 parts per
million.
The example shows the accurate control of concentration of
available chlorine in an aqueous solution attained during operation
of the improved dispensing apparatus utilizing the improved
vertical adjustment means of the present invention.
EXAMPLE II
Using the apparatus of Example I, fresh water at a temperature of
85.degree.F. was added to the dispensing apparatus at the rate of
15 gallons per hour. The magazine was filled with tableted calcium
hypochlorite containing 70 percent Ca(OCl).sub.2. At a control
setting of 4, the grid height was about 1.63 inches. The dispensing
apparatus was operated for a period of about 5 hours. Four analyses
of the treated solution taken at intervals during the period of
operation showed an available chlorine concentration from 196 to
256 parts per million was maintained, the average being 242 parts
per million.
EXAMLE III
Using the apparatus of Example I, fresh water at a temperature of
85.degree.F. was fed to the dispensing device at a rate of 7.5
gallons per hour. At a control setting of 6, the grid height was
about 1.4 inches. The dispenser was operated for a period of about
4.5 hours. Four analyses of the treated solution taken at intervals
during the period of operation showed an available chlorine
concentration ranging from 477 to 505 parts per million.
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