Water neutralizer

An improved water neutralization apparatus is disclosed comprising an elongated vertical cylindrical tank having an upper inlet and lower outlet openings. Water distributors are assembled to the tank at its upper and lower openings. A dual-seal valve is used to automatically shift water flow from normal to backflush flow paths upon actuation of a controller, comprising a timer-operated valve in a drain line connected to the dual-stem valve. In the preferred embodiment, the neutralizing mineral is 98% pure calcium carbonate.

BACKGROUND OF THE INVENTION 
(1) Field of the Invention 
This invention relates to an improved water neutralizer for raising the pH 
of household drinking water. 
(2) Related Art 
It is well-known that excess acids in drinking water can lead to 
deleterious effects. Such acids can appear in a drinking water system due 
to a variety of sources. A common source of acids in individually drilled 
wells is acid leached from rotting leaves and other vegetation into the 
groundwater system. Typically, these sources of acid can lead to a pH in 
the water of between about 5.8 and about 6.5. pH levels in this range tend 
to lead to blue-green stains in water system elements due to reaction of 
the acid in the water with copper piping and solder. 
One method of neutralizing such acid in water which is generally known in 
the art is to expose the water to a neutralizing mineral, for example 
calcium carbonate (CaCO.sub.3), for a period of time. Typically, all water 
entering a dwelling is caused to reside in a tank containing a quantity of 
this or an equivalent mineral for a period of time. The carbonates are 
leached into the dwelling water supply, and neutralize the acid. The most 
common carbonate tanks are elongated cylindrical tanks standing in a 
vertical position. The neutralizing mineral is disposed in the tank. Water 
enters the upper end of the tank, passes downwardly through the mineral, 
and drains through the lower end of the tank. 
A common practice is to form the tank of a fiber reinforced plastic 
("fiberglass") material. Such tanks have either top-mounted or 
side-mounted water inlet fittings. As the typical fiberglass tank is 
relatively thin-walled, it is difficult to provide a seal of integrity 
between a sidemounted water inlet port fitting and the tank. For this 
reason, mounting of the water inlet fitting in the end of the tank, where 
the fiberglass is thicker, is preferred. Suitable fittings are 
commercially available. Furthermore, from time to time the carbonate 
supply in the tank must be replenished. This necessitates that a mineral 
replacement port be provided in the carbonate tank. End-mounting fittings 
which provide a water inlet connection and a mineral replacement port are 
commercially available. 
It is desirable that the neutralizing mineral in the tank be backflushed at 
intervals to "fluff" it, that is, to ensure its continued efficiency, 
remove debris, etc. Automatic controllers for reversing the flow of water 
for backflushing the mineral for a short period of time, for example, ten 
minutes, at regular service intervals, for example, once per week, are 
known. Typically, these controllers and the associated valves are provided 
near the water inlet fitting. Where the water inlet fitting is affixed to 
the side of the tank, a leakage problem is commonly presented, as noted 
above. According to known methods of mounting the backflush control 
apparatus and associated valves at the end of the tank, complete 
disassembly of the control and the associated valving may be necessary in 
order that mineral replenishment can be performed. Since mineral 
replenishment typically is required at intervals of a year or less, this 
can present a significant inconvenience and expense to the homeowner. 
Another problem of conventional neutralizers is that the neutralizing 
minerals commonly used are relatively inferior. One type of mineral which 
is commonly used comprises approximately 74% calcium carbonate, the 
remainder being silicates and manganese and magnesium minerals and the 
like. The inventor's understanding is that in typical use, such minerals 
require replenishment at intervals of no more than about one year. 
Replenishment at such an interval is inconvenient, as it requires a visit 
by a plumber. 
Another deficiency of conventional neutralizers involves their method of 
assembly, and adds to their cost. It is common to employ a mixture of 
metal and plastic tubing and fittings. The plastic is ordinarily 
polyvinylchloride and the metal either copper or brass. Such mixed 
materials are usually sealed to one another at joints using a "Teflon" 
tape. (Teflon is a trademark of E. I. DuPont de Nemours and Company, 
Wilmington, Del.) More recently, Teflon pipe sealing compounds have become 
available, in which the Teflon is disposed in a thick, gluey vehicle. The 
sealing compound is applied to the threads of the male member of the joint 
using a brush. 
Use of the Teflon tape can cause a problem in that a tradeoff is made 
between the amount of the tape used and the torque applied to the joint to 
obtain a leak-free connection. If one uses a large and hence relatively 
costly amount of tape, the joint need not be tightened extremely tight to 
be leakproof; if a lesser amount of tape is used, the joint must be made 
so tight that plastic fittings tend to rupture. Use of the tape is also 
relatively time-consuming and requires some little skill on the part of 
the installer. Brush application of the Teflon-based sealing compound is 
messy, time-consuming, and is also not foolproof. 
Finally, certain known water neutralizers do not provide suitable means for 
directing water flow within the mineral bed both in normal use and upon 
backflush, so that the mineral bed is not used to its maximum advantage. 
SUMMARY OF THE INVENTION 
The invention is an improved water neutralizer which comprises an elongated 
vertical cylindrical tank having fittings in its upper and lower ends. A 
quantity of a neutralizing mineral is disposed in a bed in the tank. Water 
enters the tank by means of an inlet distributor assembly comprising a 
housing having a water inlet port and a mineral replenishment port. In 
normal use the mineral replenishment port is plugged. A water distributor 
assembly is provided to ensure that water is distributed evenly over the 
mineral bed in the tank. An outlet distributor assembly is mounted in the 
lower end of the tank, and comprises a screen for resisting passage of the 
neutralizing mineral out of the tank. A quantity of gravel is disposed in 
the bottom of the tank. A dual-seal valve, in which the two seals of the 
valve are connected by a single valve stem for simultaneous actuation, is 
provided to control flow of the water between the normal flow pattern and 
a backflush flow pattern. The dual-seal valve is operated by a controller 
which controls the opening of a control valve in a drain line. When the 
control valve in the drain line is opened, the two seals of the valve move 
simultaneously, converting the water flow pattern from normal to 
backflush. When the control valve in the drain line closes, that is, after 
expiration of a period of time sufficient for adequate backflush, the dual 
seal valve reconverts the water flow path to the normal pattern. 
In the preferred embodiment, the neutralizing mineral used is 98% calcium 
carbonate, which is much more efficient and longer lived than the 74% 
calcium carbonate material used in most known devices. Preferably the 
mineral is of larger particle size and is denser than that typically used. 
A further improvement is made by automatic dispensing of a fixed quantity 
of the Teflon joint sealing compound onto the threads of mating pipe 
fittings during assembly of the unit, whereby its assembly is more 
efficient and economical while being substantially leak-proof in service.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In the preferred embodiment of the neutralizer of the invention, it 
comprises a fiber-reinforced plastic (fiberglass) tank 10 which is 
generally cylindrical, and which extends vertically from a support member 
12 mounted to its lower end 10a to an upper end 10b. A lower water 
distributor assembly 14 fits into an orifice in the lower end 10a of the 
tank. A corresponding upper water distributor assembly 16 fits into an 
orifice at the upper end 10b of the tank. No other connections are made to 
the tank 10. In this way, the leakage problems inherent in side-mounting 
of distributors or other fittings into fiberglass tanks are avoided. 
As shown, the upper water distributor 16 is connected by an ordinary pipe 
nipple 18 to a flow controlling valve unit 20. Valve unit 20 may be a 
dual-seal valve such as the Aquamatic No. 662-A, available from 
Aqua-matic, Inc., of Rockford, Ill. This valve, as shown in Aqua-matic 
literature "Sheet 559-b," dated 5-16-62, incorporated herein by reference, 
comprises a housing member in which slide two seals 19a and 19b connected 
by a shaft. The two seals 19a and 19b move together upon variation of 
hydraulic characteristics in a drain line also connected to the valve. 
When this occurs, the normal service water flow pattern is altered to a 
backflush flow pattern. These matters are discussed in detail below and in 
connection with FIGS. 2 and 3. 
The dual-seal valve 20 is controlled by a control unit 22 which operates a 
control valve 24 in a drain line connected to the valve 20. In the 
preferred embodiment, the control unit 22 and valve 24 may each be 
comprised by a "300 series" programming control valve sold by Autotrol 
Corporation of Milwaukee, Wis., and described in Autotrol documents R202 
dated 6-84 and R210 dated 4-82, both incorporated herein by reference. The 
Autotrol unit 22 comprises a timer which can be set to open the control 
valve 24 for a predetermined period of time, for example, ten minutes, at 
predetermined intervals, for example, once per week. At these times the 
neutralizing mineral is automatically backflushed to ensure its continued 
efficacy. 
As shown schematically in FIG. 1, in use the mineral tank 10 preferably has 
in it a lowest layer 30 which may be of gravel material, for example, that 
referred to generally as "No. 20 red flint gravel." An amount 30 of this 
gravel sufficient to cover the lower distributor assembly 14 may typically 
be provided with the unit at time of shipment. Upon installation of the 
neutralizer according to the invention, a quantity 32 of the neutralizing 
mineral is added to the tank. In the preferred embodiment, this 
neutralizing mineral is 98% calcium carbonate particles of sizes generally 
greater than 20 mesh, that is, 0.145 mm mesh. This material is available 
from Hydroflo, Inc., Timonium, Md., assignee of the present application, 
as "Hydroflo Calcite." Typically about 1.5 cubic feet of this material is 
employed; this amount weighs about 165-170 pounds. In the preferred 
embodiment, the tank 10 employed is a Model 1054 fiberglass tank from 
Structural Fibers Division of ESSEF Corporation of Chardon, Ohio. The 
internal volume of this tank is sufficient that a freeboard 34 of 
approximately 18 inches remains in the tank when the neutralizing mineral 
32 and gravel 30 as described above have settled in use. This amount of 
freeboard is sufficient to ensure proper distribution of water during use. 
In normal use, the water flow pattern extends from an inlet port 34 of 
valve 20, around the valve stem 20a, through the nipple 18 and into the 
upper water distributor assembly 16, which is detailed in connection with 
FIG. 4. In normal use, the freeboard space 34 is full of water. When water 
is withdrawn, water in the freeboard space 34 flows downwardly through the 
neutralizing mineral 32 and the gravel 30. Water then flows out through 
the lower water distributor 14, through an ell 36, a nipple 38, a tee 
fitting 40, and a length of pipe 42. The neutralized water then flows into 
a service tee fitting 44 and out to household service as indicated. 
Use of the neutralizing mineral typically will add some "hardness," that 
is, dissolved minerals, to the water, so that in many cases it will be 
desirable to then treat the water in a water softener unit prior to actual 
use, as indicated generally at 46. 
FIGS. 2 and 3 show water flow in the normal mode, that is, in use, and in 
the backflush mode, respectively. As shown in FIG. 2, normal flow is from 
an inlet port 34, through the valve 20 and into the upper diverter 16. 
Water then flows generally downwardly through the tank, that is, through 
the neutralizing mineral 32 and the gravel 30, out through the lower 
distributor assembly 14, and to service, as indicated. 
In the backflush mode shown in FIG. 3, the valve 20 changes position such 
that water flow from the inlet is instead downwardly, past the service 
connection and upwardly through the lower distributor 14. The lower 
distributor 44 serves to spread water flow out into the gravel and through 
the neutralizing mineral such that the mineral tends to be "fluffed up," 
that is, lifted from any position into which it may have settled, such 
that new mineral surfaces are caused to be presented to the subsequently 
downwardly flowing water. Water then passes out through the upper 
distributor 16, around the valve stem 20a and out through a drain line. 
The control valve 24 is depicted with an X in it in FIG. 2, to indicate 
that it is closed during normal flow, and without the X in FIG. 3, to show 
that it is open for backflow. As discussed above, control valve 24 is 
operated by controller unit 22. 
As described in the Aqua-matic document incorporated by reference above, 
and as shown in FIG. 1, the dual-seal valve 20 comprises a housing 20c 
receiving a control element, in this case a bobber 20b, carried by the 
valve stem 20a. Housing 20c defines a drain port 20d connected to 
controller 22, as well as ports for the other connections shown in FIG. 1. 
In ordinary use (FIG. 2), the bobber 20b, the valve stem 20a and the two 
seals 19a and 19b are in a down position. When control valve 24 is opened, 
water flows past the upper seal 19b. This alteration of the fluid flow 
pattern causes the bobber 20b and hence the seals 19a and 19b to move 
upwardly into the backflush position shown in FIG. 3. In this case the 
normal water flow path from the inlet around the valve stem and into the 
upper distributor 16 ceases. Instead water flows downwardly past the 
service connection at service tee 44 and upwardly through the lower 
distributor 14. Backflushing in this manner "fluffs up" the gravel and the 
neutralizing mineral, ensuring that the mineral is fully used for its 
intended purpose. Water exiting the tank 10 via the upper diverter during 
backflow is passed to a drain by way of a line connected to the control 
valve 24. 
FIG. 1 shows that a tee fitting 40 connects nipple 38 to pipe 42, thus 
connecting the lower distributor assembly 14 to the service connection via 
service tee 44. The lower leg 40a of tee 40 may be employed for a drain 
connection, being plugged in ordinary use, or may have an additional valve 
41 connected to it. Valve 41 may be used to connect the household water 
supply to the system for backflush during installation by way of a hose or 
the like. Otherwise, a normal backflush operation may be carried out upon 
installation. In either case, during this initial backflush process, water 
passes through the lower distributor 14, up through the tank 10, and out 
the drain connection. This has the effect of removing any fines or other 
undesirable material from the neutralizing mineral in bed 32. 
The tee fitting 40 may in a preferred embodiment be the Model 373 
"distributor elbow" available from the Clack Corporation of Windsor, Wis. 
This fitting 40 is configured for convenient connection of either a plug 
or a valve 41 and for connection to the nipple 38 by way of a coupling 50. 
The Model 373 fitting also contains a compression fitting at its upper end 
40b, which enables convenient use of a section of copper or brass tubing 
as pipe 42 without the necessity of soldering, threading, or other complex 
assembly techniques. 
FIG. 4 shows a cross-sectional view of the upper water distributor assembly 
16. In the preferred embodiment, this may be a Model 498 distributor 
assembly available from the Clack Corporation. The distributor assembly 16 
comprises a housing 52, which is provided with a threaded water inlet port 
52a for mating with the nipple 18. The housing 52 is also formed to 
comprise a mineral replenishment port 52b, which is adapted to receive a 
plug 54 and be sealed thereto by an O-ring 56. Plug 54 may be threaded to 
receive a stem 58 which carries a distributor screen assembly 60. Screen 
assembly 60 comprises a threaded fitting 62 into which stem 58 is 
threaded, a cap 64 and a plurality of distributor disks 66, which may be 
separated by spacers 68. Spacers 68 are preferably molded integrally with 
distributor disks 66. The screen assembly 60 is held together by a 
plurality of screws 70 threaded into the fitting 62. 
As shown in FIG. 4, the distributor assembly 16 is sealed to the tank 10 by 
means of a further O-ring 72 which provides a convenient and leak-proof 
assembly. 
Use of the distributor assembly 16 shown in FIG. 4 has several advantages. 
Chief among these is that simply by unscrewing and removing the plug 54, 
the water distributor screen assembly 60 is simultaneously removed by way 
of the stem 58. This permits ready replenishment of the neutralizing 
mineral 32 as needed. In the inventor's experience, when the 98% calcium 
carbonate material described above is used, replenishment is required at 
intervals of approximately two years under ordinary circumstances. At the 
same time, location of the control unit 22, control valve 24 and dualseal 
valve 20 to one side of the tank 10, as shown in FIG. 1, simplifies the 
replenishment procedure, while allowing use of the top-mounted fitting, 
preventing leakage. By comparison, disposition of the control unit 
directly above the tank 10 would necessitate its complete removal for 
mineral replenishment or other service. 
FIG. 5 shows a cross-sectional view of the lower water distributor assembly 
14. In the preferred embodiment, the lower distributor assembly 14 is a 
Clack Corporation model 211KSPPE distributor. As in the case of the upper 
distributor 16 in FIG. 4, the lower distributor 14 comprises a screen 
assembly 71 made up of a stack of distributor disks 74 spaced by spacers 
76, which may be integrally molded with the disks 74. The disks 74 and a 
cap 78 are assembled to a threaded fitting 80, which is threaded into the 
tank 10 and sealed thereto by an O-ring 82. A number of screws 84 threaded 
into the threaded fitting 80 hold screen assembly 71 together. A further 
fitting 86 is received in a recess in the threaded member 80 and is 
internally threaded to receive a standard pipe-threaded ell 36. Ell 36 is 
sealed to fitting 80 by way of an O-ring 92. Ell 36 provides a connection 
between the lower water distributor assembly 14, nipple 38, tee fitting 
40, piping 42 connected to further tee fitting 44. 
The use of the O-rings 72 and 82, to seal the upper and lower distributor 
assemblies 16 and 14 respectively to the tank 10, and the use of O-rings 
92 to seal ell 36 to fitting 80 provides an advantage in that this 
simplifies parallel alignment of the members receiving nipples 18 and 38, 
that is, of inlet port 52a and ell 36. Such O-ring sealed assemblies are 
somewhat less critical concerning the amount of torque which must be 
exerted to effect a good seal than are joints sealed only by sealing 
compounds or Teflon tape, which must be tightened at least to a minimum 
torque. Use of the O-rings 72 and 92 allows use of an assembly sequence as 
follows. The O-rings are lubricated with a non-petroleum based lubricant. 
The inlet distributor assembly 16 is threaded into the tank 10 and 
tightened. A hole 12a aligned with the water inlet port 52a in the inlet 
distributor assembly (FIG. 4) is drilled in base 12. The lower water 
distributor assembly 14 is threaded into the base of the tank 10 and 
tightened until the ell 36 is aligned with the hole 12 a. (Alternatively, 
the lower distributor assembly 14 can be assembled and hole 12a drilled 
prior to assembly of the inlet distributor assembly 16.) By comparison, 
assembly of the unit of the invention using thread-sealing tapes or 
compounds, that is, on the threads of the distributor assemblies 14 and 16 
which mate with the threads of the tank 10 and/or the threads of ell 36 
mating with fitting 80 would necessitate that these assemblies be 
tightened with a certain minimum torque in order that secure seals could 
be effected. In many cases the inlet port 52a and ell 36 would not be 
aligned. This would necessitate more complex external piping connecting 
ell 36 and service tee 44. 
In a preferred assembly technique, after assembly and alignment of the 
upper and lower water distributors as described, the nipple 38, tee 40, 
pipe 42, service tee 44, and dual-seal valve 20 are assembled. The entire 
assembly is may be placed into the tank 10 prior to shipment. Upon 
installation, the controller 22 and control valve 24 are added, the system 
is plumbed to the household inlet and service lines, an initial charge of 
the neutralizing mineral 32 is placed in the tank, and the system is 
initially backflushed as described bove. 
A further improvement according to the invention involves use of a 
particular assembly technique. This involves application of metered 
amounts of a Teflon-based sealing compound to the threads of the male 
members assembled by threads which are not sealed by O-rings. The 
application is preferably made using a particular applicator machine, a 
model 998400 "Dial-a-Seal" applicator sold by the Loctite Corporation of 
Newington, Conn. The preferred sealant is Permatex "Thread Sealant with 
Teflon," Part 14d, also sold by Loctite. The inventor finds that use of 
this material, particularly when applied by this applicator, provides a 
reliable, economical and leak-proof joint. 
While a preferred embodiment of the invention has been discussed in detail, 
it will be realized by those of skill in the art that numerous 
modifications and improvements can be made thereto without departure from 
spirit and scope of the invention, which is therefore not to be limited by 
the above exemplary embodiment, but only by the following claims.