Apparatus and method for injecting dry particulate material in a fluid flow line

An apparatus and method for injecting dry particulate material into a fluid flow line including a removable material supply unit (18) having an outer rigid container (55) and a sealed flexible bag (54) for the dry particulate material. The removable material supply unit (18) is mounted on a container support (13) above a mixing chamber (12) with a valve member (40) controlling the flow or dispensing of the dry particulate material into the mixing chamber (12). A pump (32) when energized exerts a vacuum in the mixing chamber (12). Water enters the mixing chamber (12) from an elliptical discharge opening (10) tangential to mixing chamber (12) to provide a vortex. Pump (32) exerts a vacuum within the mixing chamber (12) above the level of the water so that any upward migration of moisture from the water in the mixing chamber (12) is prevented by the vacuum when pump (30) is energized. Additional mixing occurs in a dynamic mixing manifold (28) to provide a solution of the dry particulate material within the water for injection of the solution within a pressurized fluid flow line (35) to a suitable facility (S).

FIELD OF THE INVENTION 
This invention relates to an apparatus and method for injecting dry 
particulate material into a pressurized fluid flow line, and more 
particularly to such an apparatus and method in which the dry particulate 
material is first dispensed within a mixing chamber for mixing with the 
fluid and subsequently injected within the flow line. 
DESCRIPTION OF THE PRIOR ART 
One of the problems involved with the injection of dry particulate material 
which includes powdered and granular materials, such as calcium 
hypochlorite or sodium hypochlorite is in maintaining a dry atmosphere for 
the dry particulate material when positioned within the injection system 
as well as storage. This is desired in order to preserve the quality of 
the dry particulate material as well as to prevent the escape of possibly 
contaminating fumes and dust residue from the dry particulate material. 
Thus, exposure to atmosphere of the dry particulate material is not 
desired. 
Another problem involved in the injection of water soluble dry particulate 
material into a liquid flow line is in providing for the complete mixing 
of the water soluble particulate material into solution with the carrier 
liquid prior to injection into the pressurized flow line. It is desirable 
that none of the undissolved particulate material remain suspended within 
the carrier liquid. 
An injection system for injecting dry particulate material into a 
pressurized liquid flow line must also provide means for injecting a 
precisely measured quantity of the dry particulate material into the 
carrier line. The amount of the injected dry particulate material must be 
adjustable as desired. 
Heretofore, various injection systems have been provided for injecting a 
dry particulate material into a liquid carder fluid such as water. For 
example, reference is made to U.S. Pat. No. 3,638,833 dated Feb. 1, 1972 
in which an apparatus is provided for chlorinating a swimming pool. A 
container for the water soluble chlorine powder has a thin plastic cover 
for the discharge opening which is cut upon mounting of the container onto 
the injection apparatus. The chlorine powder flows by gravity from the 
container into a measuring chamber where it flows downward into a mixing 
chamber with water. The mixed chlorine powder and water are discharged by 
gravity from the mixing chamber. 
U.S. Pat. No. 3,456,801 dated Jul. 22, 1969 also shows an apparatus for 
feeding dry particulate material into a swimming pool in which the 
chlorine powder is fed by a screw feeder into a mixing chamber in which 
the level of water is controlled by a float. The water is discharged into 
the mixing chamber from an inlet in the bottom of the mixing chamber for 
agitation of the water in the mixing chamber to minimize any settling of 
insoluble solids when the dry particulate material, such as calcium 
hypochlorite is mixed with the water. 
U.S. Pat. No. 4,878,320 dated Nov. 7, 1989, is directed to an abrasive 
blast cleaning system that utilizes a pressure differential for the 
metering of a dry particulate material into an air flow line. A discharge 
nozzle is connected to the air flow line and water is mixed with the air 
entrained particulate material at the nozzle for discharge against a 
surface to be cleaned. 
SUMMARY OF THE INVENTION 
The present invention is directed particularly to an apparatus and method 
for injecting a dry particulate material in a pressurized fluid flow line. 
The dry particulate material may be a powdered material or a granular 
material and preferably but not necessarily water soluble. The fluid flow 
line can be open to atmosphere or a pressurized liquid line. The dry 
particulate material is mixed with a liquid, usually water, and normally 
forms a solution that is injected in the pressurized flow line. The dry 
particulate material is sealed within an airtight container which is 
impervious to moisture. The container which is formed of a generally rigid 
material has an inner flexible liner in contact with the dry particulate 
material. The flexible liner is responsive to a vacuum upon the feeding of 
the particulate material from the container and generally follows a 
conduit of dry particulate material during unloading from the container. 
The container seal is punctured when the container is installed within the 
apparatus for a controlled feeding of the dry particulate material into a 
mixing chamber with water positioned below the container. 
The bottom of the mixing chamber receives a continuous flow of fluid. Fluid 
enters the chamber tangent to the outer wall and exits circumferentially 
around the center poppet support tube creating a vortex. The fluid vortex 
evenly dispenses the dry granules throughout a given volume of fluid as it 
passes through the chamber. Vacuum exerted by the flowing stream of water 
across the bottom of the mixing chamber provides a barrier to the upward 
migration of any moisture into the dry particulate material with the 
container. Also, the vacuum exerted in the upper portion of the mixing 
chamber draws the dry particulate material downward into the fast flowing 
stream of the liquid. A supply of water flowing across the mixing chamber 
is restricted by a metering valve having an orifice therein of a 
predetermined size for the desired amount of flow and vacuum. After the 
dry particulate material is drawn into the moving flow stream at the 
bottom of the mixing chamber, the mixture of the liquid and particulate 
material is mixed further within a dynamic mixing chamber which consists 
of a series of coiled tubing and baffles to provide complete blending of 
the granulated material into solution. For water soluble particulate 
material, a solution is obtained with a minimum of any suspended 
particles. The mixing chamber is constructed and arranged to provide an 
adequate volume of liquid in the bottom of the mixing chamber to 
accomplish complete wetting of the particulate material in the liquid 
prior to entering the dynamic mixing chamber. The particulate material is 
typically dissolved before entering the pump for discharge into the 
pressurized main flow line in which the mixture is injected. 
The present invention would have various applications such as for use with 
home and commercial swimming pools, residential and public water wells, 
waste water systems, sprinkler systems, agricultural irrigation systems, 
sprinkler systems that deliver granulated fertilizers, pesticides and 
herbicides and water softening agents, as examples. It is desirable for 
practically all powders or granulated materials to be free of moisture as 
most powders and granulated materials are moisture sensitive. Atmospheric 
moisture and other airborne contaminants may contaminate the dry 
particulate material and the present invention provides a sealed system in 
which the dry particulate material is protected from moisture even after 
the sealed container is opened and while flowing into a moving liquid 
stream for mixing therewith. A vacuum is continuously exerted in the 
mixing chamber when a valve member for dispensing the dry particulate 
material is in an open position thereby preventing migration of any 
moisture from the flowing stream of water at the bottom of the mixing 
chamber into the dry particulate material in the container. In various 
other injection systems utilizing only gravity to propel the granulated 
material from the storage area to the liquid flow, an upward migration of 
moisture usually occurs to contaminate the dry particulate material in the 
container and clog the orifice where the dry particulate material exits 
the storage container, thus rendering the system inoperable. The present 
invention eliminates this problem. 
It is an object of the present invention to provide an apparatus for 
injecting dry particulate material into a pressurized fluid flow line 
while preventing the upward migration of moisture from the liquid flow 
line into a container for the dry particulate material being fed or 
dispensed into the flow line. 
A further object of the present invention is to provide such a system and 
apparatus in which a vacuum is continuously exerted in the mixing chamber 
in which the dry particulate material is dispensed for drawing the dry 
particulate material from the dispensing device in an open position 
downward into the liquid flow line while preventing any upward migration 
of moisture from the liquid in the mixing chamber. 
An additional object of the invention is to provide a container or 
dispenser for the dry particulate material which as the dry particulate 
material sealed in a membrane in the container with the membrane 
collapsing upon dispensing for the dry particulate material into the 
mixing chamber, thus eliminating contamination of the environment and 
contact with humans of potentially dangerous chemicals. 
Other objects, features, and advantages of the invention will become more 
apparent after referring to the following specifications and drawings.

DESCRIPTION OF THE INVENTION 
Referring now particularly to FIG. 1, a system for injecting a dry 
particulate material into a pressurized fluid is illustrated schematically 
for a water treatment facility or plant in which a dry particulate 
chlorinating agent such as calcium hypochlorite is injected into a 
pressurized water line leading to the water treatment facility. While a 
water treatment facility is illustrated as an example of an application of 
the present invention, it is to be understood that the present invention 
has various other uses, such as swimming pools, various water supply 
systems, waste water systems, and sprinkler systems injecting fertilizers 
and pesticides as well as food processing injecting various granulated 
materials. Also, while water is illustrated as the carrier fluid for 
mixing with the dry particulate material, other liquids may be utilized 
with the present system, such as food processing syrups, milk and fuels. 
A water tank or reservoir shown at 4 is supplied with water from a suitable 
source by pipe 1. A float 3 connected to pipe 1 stops the flow of water 
into tank 4 when the water shown at 5 reaches a predetermined level shown 
6 as well known. Water is supplied from tank 4 through line 7 to a 
metering valve generally indicated at 8 and having an adjustable orifice 
therein to restrict or control the supply of water from metering valve 8 
through inlet line 9 to a mixing chamber generally indicated at 12. Inlet 
line 9 has an elliptical outlet opening 10 which is directed tangentially 
to the inner circumference of mixing chamber 12 to provide a swirling 
action as the water enters chamber 12 for creating a vortex. An outlet 
line 27 leads from mixing chamber 12 to a dynamic mixing manifold 28 
comprised of coiled tubing 30 and mixing baffles 29 in which the water and 
water soluble dry particulate material is completely mixed to form a 
solution for discharge into pressurized line 35. Pressurized line 35 has a 
filter F and leads to a facility such as a water treatment plant S at 
which it is desired to add or inject the solution containing the dissolved 
particulate material. A pump 32 is connected by line 31 to dynamic mixing 
chamber 28. A line check valve 34 in delivery line 33 to line 35 prevents 
fluid from entering the system from the pressurized line 35. 
Pump 32 may comprise a positive displacement diaphragm pump or other 
positive displacement pump for a relatively small system, while a larger 
system may utilize a high volume centrifugal pump. It should be noted that 
in the event the present invention is utilized with a swimming pool, a 
separate external pump is not required for operation. The system may be 
installed on the suction side of an existing recirculating pump for the 
swimming pool, thereby eliminating the need for a separate pump. Thus, the 
vacuum exerted by a particular system may vary depending on the type of 
pump and volumetric capacity of the various system components. 
Inlet line 9 and outlet line 27 connected to mixing chamber 12 are arranged 
so as to create a vortex as fluid enters and exits the chamber. A base 20 
for mixing chamber 12 has a lower frusto-conical inner surface 21 and an 
upper cylindrical surface 22. The elliptical outlet opening 10 from inlet 
line 9 enters base 20 in a tangential direction relative to the inner 
cylindrical surface 22 of base 20 above frusto-conical inner surface 21. 
An outlet port 19 in base 20 below frusto-conical surface 21 leads to 
outlet line 27. A bottom opening 23 in base 20 receives a vertically 
movable valve control rod or stem 16. An annulus 17 is formed about stem 
16 adjacent port 19. A transparent cylindrical sleeve 15 is supported on 
base 20 for defining mixing chamber 12 along with base 20. 
For providing a supply of dry particulate material for mixing chamber 12, a 
separate transportable material supply unit 18 has an inner flexible bag 
54 of dry particulate material positioned within an outer rigid container 
55. Material supply unit 18 is removably mounted on dispensing device 25. 
The dry particulate material from bag 54 flows into a hopper defined by 
dispensing device 25 and is metered or dispensed form dispensing device 25 
into mixing chamber 12 as will be explained further below. FIGS. 1 and 2 
show the apparatus in an inoperable position while FIGS. 4 and 5 show the 
apparatus in an operable position with dry particulate material being 
metered into mixing chamber 12. A vacuum is continuously exerted by pump 
32 within mixing chamber 12 while the dry particulate material is being 
dispensed or fed from bag 54 into the mixing chamber 12. The continuous 
exertion of a vacuum within mixing chamber 12 while the dry particulate 
material is being dispensed as shown in FIG. 4 prevents the migration of 
moisture from the surface 11A of the swirling water in mixing chamber 12 
into the particulate material within the supply unit 18. A rate of water 
flow sufficient to create a vortex, such as five (5) gallons per minute, 
and a vacuum two (2) and four (4) inches of water column has been found to 
be satisfactory for the dispensing of calcium hypochlofite into a mixing 
chamber having a diameter of eight (8) inches, for example. The fluid 
level in mixing chamber 12 when the system is in operation is determined 
primarily by the velocity of liquid being drawn through the system. As the 
velocity or volume of water increases in mixing chamber 12, the resulting 
vortex generated forces water to rise higher on the outer interior walls 
of the vacuum mixing chamber 12. 
Referring to FIG. 2, an enlarged view of material supply unit 18 and mixing 
chamber 12 is shown in an inoperable position in which dispensing device 
25 is positioned between mixing chamber 12 and supply unit 18 for 
controlling the flow of particulate material from supply unit 18 to mixing 
chamber 12. Dispensing device 25 includes a container support or 
receptacle generally indicated at 13 which supports supply unit 18 for the 
particulate material being dispensed. Container support 13 includes a 
generally cylindrical housing supported on the upper end of cylindrical 
sleeve 15 and having a central bore 14 which defines a hopper to receive 
the dry particulate material from flexible bag 54. Central bore 14 is 
defined by a lower frusto-conical surface 24 and a reduced diameter lower 
bore portion forming a lower discharge opening 26 for the particulate 
material. An enlarged upper bore portion 36 above frusto-conical surface 
24 is defined by central bore 14. A pair of arcuate piercing blades or 
knives 37 are secured to lower surface 24 and extend vertically therefrom. 
Knives 37 have sharp outer edges 38 thereon which converge at an upper 
apex 39. 
Valve control rod or stem 16 controls the flow of particulate material from 
lower discharge opening 26 and has a valve member or poppet generally 
designated at 40 on its upper end. Poppet 40 has a fluted end defining 
four grooves between partitions 42 for the downward passage of particulate 
material through the grooves in a lowered retracted position of poppet 40 
as shown in FIG. 5. The grooves terminate at a reduced diameter portion 44 
of stem 16 and an elastomeric annular seal 46 extends about reduced 
diameter stem portion 44. Annular seal 46 seats against a lower annular 
seat or shoulder 49 on housing 13 about lower discharge opening 26 in the 
raised closed positions of poppet 40. 
The four partitions 42 or un-routed portions of poppet 40 are the same 
diameter as reduced diameter stem portion 44 to provide alignment for stem 
16 and poppet 40 as poppet 40 moves up and down within lower discharge 
opening 26. Seal 46 in the closed projected position of poppet 40 shown in 
FIG. 3 is spaced vertically from the fluted grooves of poppet 40 by the 
length of reduced diameter stem portion 44. Upon the upward movement of 
poppet 40 from the lower retracted position as shown in FIG. 4, flow of 
particulate material through discharge opening 26 stops when the upper end 
of reduced diameter stem portion 44 reaches seat 49 prior to contact of 
seal 46 with seat 49. This stoppage of flow prior to seal contact greatly 
reduces any accumulation of granulated material between seal 46 and seat 
49. 
A spring 48 continuously urges poppet stem 16 and poppet 40 to a seated 
closed position within lower discharge opening 26 as shown in FIGS. 2 and 
3. A bellows type seal 52 is mounted about poppet stem 16 to provide a 
seal for bottom opening 23 to prevent leakage from atmosphere to chamber 
12. An electromagnet is shown at 50 connected to poppet stem 16 for 
opening of poppet 40. An adjustable timer 51 is connected to electromagnet 
50 to permit energizing of electromagnet 50 at predetermined time 
intervals for opening and closing of poppet 40 for the desired flow of dry 
particulate material from container 18. Spring 48 acting against 
electromagnet 50 continuously urges poppet 40 to a closed position 
relative to lower discharge opening 26. Although an electromagnet 50 is 
used in this illustration as a means to operate poppet stem 16, other 
means may be employed such as an pneumatic cylinder or electromechanical 
lever, for example. 
As shown in FIG. 1, the water level 11 of the water in mixing chamber 12 is 
shown at the level 6 of the water within tank 4 when pump 32 is inoperable 
and a vacuum is not being exerted within chamber 12. When pump 32 is 
energized, a vacuum is exerted from pump 32 through line 27 to mixing 
chamber 12 and water is discharged from outlet line 33 to permit flow of 
water within chamber 12 from opening 10. Upon the exertion of a vacuum in 
chamber 12, water within chamber 12 is lowered an amount dependent on the 
water velocity and amount of vacuum, and a swirling action is created from 
the tangential flow of water from opening 10. Arrows shown in FIG. 4 
indicate the fluid vortex generated within chamber 12 as a result of the 
tangential entrance of liquid at inlet opening 10 in combination with the 
lower frusto-conical surface 21 of mixing chamber 12. The fluid vortex 
aids in rinsing the internal surface of mixing chamber 12 as well as 
providing an even distribution of the particulate material into the liquid 
as it passes through mixing chamber 12. Upon de-energizing of pump 32, the 
water level in mixing chamber 12 returns to the same level as tank 4 as 
indicated in FIG. 1. 
Referring particularly to FIG. 4, the metering and injecting of the 
particulate material into mixing chamber 12 is illustrated with the 
particulate material being dispensed into the swirling fluid vortex. With 
poppet 40 in a lowered open position, the particulate material passes 
through discharge opening 26 into chamber 12 where it enters a swirling 
fluid vortex and is gradually carried down and out of chamber 12 by outlet 
port 19 and outlet line 27 into dynamic mixing chamber 28. The particulate 
material is gradually dissolved or reduced to a complete solution in 
mixing chamber 28 before entering pump 32 for delivery to pressurized line 
35 which forms a treated solution line to water treatment plant S as shown 
in FIG. 1. When pump 32 is energized, a continuous vacuum is exerted 
within chamber 12. Cylindrical sleeve 15 is formed of a transparent or 
translucent material to provide for visual observation of the injection 
process. Other means for observing the process could include an 
observation port with a translucent window, for example. The provision to 
observe the injection process may be helpful, but is not necessary to the 
operation of the system. 
The particulate material prior to dispensing should be in a sealed 
container so that contamination, particularly from moisture, is prevented. 
For this purpose the particulate material may be stored initially in a 
sealed plastic bag 54 formed, for example, of polyethylene having an 
optimum thickness between two (2) to five (5) inches. The open end of bag 
54 is heat sealed after being filled with the particulate material. It is 
desirable that flexible bag 54 be positioned within the generally rigid 
container 55 prior to filling. Rigid container 55 has a generally 
cylindrical body with a removable upper lid or cover 56 and a removable 
bottom cover 57. A circular band of adhesive 58 is applied to the inner 
peripheral surface of container 55 and an air tight seal is formed between 
bag 54 and the band of adhesive 58 when bag 54 is filled with particulate 
material after being positioned within container 55 with upper cover 56 
removed. Bag 54 is first positioned within container 55 and then filled 
with particulate material. The upper end of bag 54 is then heat sealed at 
60 with the adhesive from circular adhesive band 58 engaging the outer 
periphery of bag 54 in a sealing relation. The material supply unit 18 
including container 55 with filled bag 54 as shown in FIG. 5 may be easily 
transported to the material dispensing device 25 for insertion. As an 
example of a container 55 and bag 54 which has been found to be 
satisfactory for calcium hypochlorite or sodium hypochlorite, a 
polyethylene bag having a thickness of five (5) mils is placed within 
container 55 which may be formed of a polyvinylchloride (PVC) material 
having a non-porous surface. Container 55 may, for example, have a 
diameter of eight (8) inches with bag 54 being filled with the particulate 
material at a weight of around twenty five (25) pounds. The upper end of 
bag 54 is then heat sealed. Circular adhesive band 58 provides a 
continuous circular air tight seal between bag 54 and container 18. 
Prior to insertion of container 55 and filled bag 54 within container 
support 13, bottom cover 57 is removed from container 55 exposing bag 54. 
Surface friction between bag 54 and the inner peripheral surface of 
container 55, in combination with adhesive band 58 adheres bag 54 to 
container 55 for maintaining an air tight seal between bag 54 and 
container 55. When container 55 and bag 54 are inserted into enlarged 
diameter bore 36 which forms a hopper for container support 13 as shown in 
FIG. 4, the smooth exterior surface of container 55 first contacts an 
upper annular seal 62. As container 55 moves further downwardly, seal 63 
is engaged by container 55 and the exposed bottom of bag 54 is pierced by 
edges 38 of piercing knives 37 allowing the particulate material to flow 
from bag 54 down into the hopper and a holding area defined by 
frusto-conical surface 24 above poppet 40. The additional capacity from 
the holding area allows an installed material supply unit 18 to be 
removed, and a new material supply unit 18 to be installed before the 
system has completely exhausted the supply of particulate material 
remaining from the previous material supply unit 18. 
When container 55 is pressed downwardly to its maximum depth against a 
shoulder in bore 36, the second lower external seal 63 further assures the 
air tight seal between container 18 and upper container support 13. As bag 
54 is evacuated, the empty portion of bag 54 collapses as shown in broken 
lines in FIG. 4 towards the bottom of the container under the influence of 
the vacuum from chamber 12, as air leakage from atmosphere past upper 
cover 56 urges bag 54 against its contents. When it is desired to replace 
an emptied or partially emptied bag 54, upper cover 56 of the used 
container 55 is removed to permit visual inspection of the level of 
particulate material within container 18. 
Since seals 62, 63 seal the exterior of material supply unit 18, and the 
circular adhesive band 58 seals the bag 54 against the inner surface of 
cylindrical body 55, the contents of bag 54 are effectively isolated from 
the environment even though bag 54 has been punctured by knives 37. Since 
the interior of bag 54 is exposed to the vacuum from chamber 12 in the 
open position of poppet 40, the upper portion of bag 54 exposed to 
atmosphere follows the level of particulate material remaining in bag 54 
until the contents of bag 54 are completely emptied. 
Referring now to FIG. 8, a modification of the present invention is 
illustrated in which a hopper generally indicated at 70A is mounted on 
hopper support 13A and has a body 72A with an upper removable cover or lid 
74A. Body 72A and cover 74A have mating flanges 76A which have elastomeric 
seals 78A thereon. To fill hopper 70A with dry particulate material, cover 
74A is removed and the dry particulate material shown at 80A fills hopper 
70A up to flanges 76A. Then, a flexible plastic cover shown at 82A is 
positioned over the particulate material with a marginal portion 84A of 
cover 82A positioned over lower flange 76A. Cover 74A is then positioned 
over body 72A with mating flanges 76A contacting flexible cover 82A. Next, 
swing brackets 76A pivotally mounted on body 72A are swung over flanges 
76A and toggle handles 87A are actuated for clamping flanges 76A in air 
tight relation against flexible cover 82A. Upon metering or feeding of the 
dry particulate material into the mixing chamber upon actuation of poppet 
stem 16A and poppet 40A a vacuum is exerted against the particulate 
material within hopper 70A and flexible cover 82A follows the upper 
contour of the particulate material as the contents are unloaded from 
hopper 70A. As the inner surface of flexible cover 82A is sealed from 
atmosphere by elastomeric seals 78A, atmospheric pressure on the outer 
surface of flexible cover 82A urges cover 82A downwardly into contact with 
the upper surface of dry particulate material 80A. An opening 88A in cover 
74A provides a vent to atmosphere. Flexible cover 82A may be formed of 
polyethylene, for example. The remainder of the apparatus (not shown) is 
similar to the apparatus shown in FIGS. 1-7. Thus, in the embodiment of 
FIG. 8, a separate transportable container for the dry particulate 
material is eliminated, which may be desirable under certain conditions of 
use. It is apparent that other various means for supplying the dry 
particulate material to the dispensing means may be provided within the 
scope of the present invention. 
The amount of granulated material to be mixed with water for injecting into 
the main flow line, such as pressurized line 35, is predetermined, and 
this amount may be varied by selected adjustment of both the duration and 
frequency of the opening and closing cycles of the fluted poppet 40 by 
timer 51. The flow rate of water passing through the system remains 
constant but the volume of particulate material is varied thus regulating 
or controlling the concentration of additive or particulate material in 
the solution. 
Referring to FIG. 1, the height of water level 11 in mixing chamber 12 in 
the inoperable position of the apparatus is determined by the position of 
the adjustable float 3 in water tank 4. A substantial distance such as at 
least four (4) inches is provided between the water level 11 in mixing 
chamber 12 and the air tight seal 46 provided by poppet 40 in the closed 
position of poppet 40. This distance in combination with seal 46 prevents 
migration of moisture past seal 46 and into the particulate material above 
opening 26 when the system is not operating. When in operation, the vacuum 
exerted by pump 32 within container 12 draws the water level downwardly 
and prevents migration of moisture from water surface 11A past lower 
discharge opening 26. 
The mixing of particulate material into solution is only partially 
completed within mixing chamber 12. The primary purpose of mixing chamber 
12 is to entrain the particulate material into the flowing solution 
stream. As the partially dissolved solution leaves mixing chamber 12 and 
enters dynamic mixing chamber 28, the solution passes through a series of 
baffles 29 and coiled tubing 30 where mixing is completed prior to 
entering pump 32. Pump 32 then pushes the mixed solution into delivery 
line 33, passing through an in-line check valve 34 prior to entering the 
flowing product stream 35 that is to be treated. Depending on the 
solubility of the particulate or granulated material, additional dynamic 
mixing chambers similar to chamber 28 for example, can be added on the 
discharge side of pump 32 in order to effect complete mixing of the 
particulate material into solution. 
While pressurized line 35 is illustrated in FIG. 1 as leading to a water 
treatment plant for injection of calcium hypochlorite, it is apparent that 
pressurized line 35 which normally includes a predetermined particulate 
material in solution with water, could also be connected, for example, to 
a swimming pool, irrigation system, a cooling tower treatment facility, or 
a waste water treatment facility. 
While the present invention is particularly adapted for utilization with 
water soluble dry particulate material, it is to be understood that the 
present invention may be utilized with dry particulate material which is 
not water soluble or only partially water soluble, such as various 
fertilizers, pesticides, or herbicides, which may be injected into various 
sprinkler systems such as golf course greens or any sprinkler or liquid 
delivery system that would have application for granulated fertilizers, 
pesticides, or herbicides. It is apparent that various types of valving 
means can be provided to control the flow of dry particulate material into 
the mixing chamber. The present invention includes a dispensing means 
which has been found to function satisfactorily. 
Since certain changes or modifications may be made in the disclosed 
embodiment without departing from the inventive concepts involved, it is 
the aim of the appended claims to cover all such changes and modifications 
falling within the true spirit and scope of the present invention.