U.S. patent application number 10/430170 was filed with the patent office on 2004-11-11 for system and process for removing contaminants from storm water.
Invention is credited to Maresca, Frank R. JR., Markee, John, Peters, John JR., Peters, John W..
Application Number | 20040222159 10/430170 |
Document ID | / |
Family ID | 33416197 |
Filed Date | 2004-11-11 |
United States Patent
Application |
20040222159 |
Kind Code |
A1 |
Peters, John JR. ; et
al. |
November 11, 2004 |
System and process for removing contaminants from storm water
Abstract
A system for treating storm water in situ within a storm water
drainage system includes a process chamber and treatment material
that is contained within the process chamber. Preferably, the
treatment material is a material that is effective in removing
heavy metals from storm water, such as zeolite. A first passageway
is provided for admitting storm water from the storm water drainage
system into the process chamber. A second passageway is provided
for returning storm water from the process chamber back to the
storm water drainage system. Also disclosed is a method of
retrofitting conventional storm water drainage systems so as to
render them capable of effectively removing heavy metals from storm
water passing therethrough.
Inventors: |
Peters, John JR.;
(Manorville, NY) ; Peters, John W.; (Centereach,
NY) ; Markee, John; (Selden, NY) ; Maresca,
Frank R. JR.; (Massapequa, NY) |
Correspondence
Address: |
KNOBLE & YOSHIDA, LLC
Eight Penn Center
Suite 1350
1628 John F. Kennedy Blvd.
Philadelphia
PA
19103
US
|
Family ID: |
33416197 |
Appl. No.: |
10/430170 |
Filed: |
May 5, 2003 |
Current U.S.
Class: |
210/688 ;
210/170.03; 210/287; 210/747.3 |
Current CPC
Class: |
C02F 1/42 20130101; C02F
2101/20 20130101; C02F 2303/24 20130101; C02F 2001/425 20130101;
B01J 39/14 20130101; C02F 2103/001 20130101 |
Class at
Publication: |
210/688 ;
210/747; 210/170; 210/287 |
International
Class: |
C02F 001/42 |
Claims
What is claimed is:
1. A method of removing heavy metals from storm water, comprising:
(a) positioning a treatment system within a drainage space through
which storm water is designed to flow, said treatment system
comprising a process chamber in which a treatment material that is
capable of absorbing heavy metals from storm water is disposed,
said treatment system further comprising a first passageway for
admitting storm water from the drainage space into the process
chamber and a second passageway for permitting treated storm water
to return from the process chamber to the drainage space; and (b)
permitting storm water to flow through the drainage space, whereby
it is at least partially treated by the treatment system.
2. A method of removing heavy metals from storm water according to
claim 1, wherein said treatment material comprises a zeolite
material having an ion exchange capacity.
3. A method of retrofitting a storm water drainage system for the
purpose of reducing heavy metal contamination of storm water that
may flow therethrough, comprising: (a) reconfiguring a storm water
drainage system that has a drainage space through which storm water
is designed to flow by installing a treatment system, the treatment
system comprising a process chamber in which a treatment material
that is capable of absorbing heavy metals from storm water is
disposed, the treatment system further comprising a first
passageway for admitting storm water from the drainage space into
the process chamber and a second passageway for permitting treated
storm water to return from the process chamber to the drainage
space; and (b) permitting storm water to flow through the
retrofitted storm water drainage system.
4. A method of retrofitting a storm water drainage system according
to claim 3, wherein said treatment material comprises a zeolite
material having an ion exchange capacity.
5. A system for treating storm water in situ within a storm water
drainage system, comprising: a process chamber; treatment material
contained within said process chamber, said treatment material
being capable of absorbing heavy metals from storm water; a first
passageway for admitting storm water from the storm water drainage
system into said process chamber; and a second passageway for
permitting treated storm water to return from the process chamber
to the storm water drainage system.
6. A system for treating storm water according to claim 5, wherein
said treatment material comprises a zeolite material having an ion
exchange capacity.
7. A system for treating storm water according to claim 5, wherein
said process chamber comprises a receptacle that is constructed and
arranged to be positioned beneath a storm drain.
8. A system for treating storm water according to claim 7, wherein
said receptacle comprises a bottom surface for supporting said
treatment material and at least one sidewall, and wherein said
second passageway is defined in said sidewall.
9. A system for treating storm water according to claim 7, further
comprising an access opening defined in said receptacle for
permitting said treatment material to be removed and replaced with
new treatment material.
10. A system for treating storm water according to claim 9, further
comprising a removable cover positioned over said access
opening.
11. A system for treating storm water according to claim 5, wherein
said treatment material is contained within at least one mesh bag
that is positioned within said process chamber.
12. A system for treating storm water according to claim 11,
wherein said mesh bag comprises engagement means for permitting
said bag to be engaged and lifted for deployment and maintenance
purposes.
13. A system for treating storm water according to claim 5, further
comprising bypass means defining a bypass passage, said bypass
passage being capable of handling a bypass flow of at least 5000
gallons per minute.
14. A system for treating storm water according to claim 5, further
comprising filter means positioned in said first passageway for
preventing debris from entering said process chamber.
15. A system for treating storm water according to claim 5, wherein
said process chamber is defined within a vault, said first
passageway being defined within said vault in communication with a
first storm water conduit, said second passageway also being
defined within said vault and being in communication with a second
storm water conduit.
16. A system for treating storm water according to claim 15,
further comprising filter means positioned within said first
passageway for preventing debris from entering said process
chamber.
17. A system for treating storm water according to claim 15,
further comprising treatment material retention means for
preventing said treatment material from escaping into said second
passageway.
18. A system for treating storm water according to claim 17,
wherein said treatment material retention means comprises a screen
that is positioned between said process chamber and said second
passageway.
19. A system for treating storm water according to claim 15,
further comprising a first access opening defined in said vault for
permitting said treatment material in said process chamber to be
removed and replaced with new treatment material.
20. A system for treating storm water according to claim 19,
further comprising a second access opening defined in said vault
for permitting debris to be removed from said first passageway.
21. A system for treating storm water according to claim 19,
further comprising a removable cover that is mounted to removably
cover said first access opening.
22. A system for treating storm water according to claim 15,
further comprising positioning means located in said process
chamber for positioning said treatment material within said process
chamber.
23. A system for treating storm water according to claim 5, wherein
said process chamber is defined within a conduit, said first
passageway comprising an upper portion of said conduit, said second
passageway comprising a lower portion of said conduit that is
constructed and arranged to permit storm water to drain into
surrounding soil.
24. A system for treating storm water according to claim 23,
further comprising filter means positioned within said upper
portion of said conduit for preventing debris from entering said
process chamber.
25. A system for treating storm water according to claim 24,
wherein said filter means comprises a debris basket that is
removably positioned within said upper portion of said conduit,
said debris basket being shaped and sized so as to be removable by
withdrawing said debris basket through said upper portion of said
conduit.
26. A system for treating storm water according to claim 23,
wherein said conduit is positioned so as to be substantially
vertical in orientation.
27. A system for treating storm water according to claim 23,
wherein said lower portion of said conduit is positioned within a
drainage chamber, said lower portion of said conduit having at
least one drainage opening defined therein for permitting storm
water to flow therefrom into said drainage chamber.
28. A method of removing heavy metals from storm water, comprising:
introducing into a storm water drainage system a treatment material
that is capable of absorbing heavy metals from storm water.
29. A method of removing heavy metals from storm water according to
claim 28, wherein said step of introducing into a storm water
drainage system a treatment material that is capable of absorbing
heavy metals from storm water comprises deploying the treatment
material in at least one mesh bag.
30. A method of removing heavy metals from storm water according to
claim 29, wherein said step of deploying the treatment material in
at least one mesh bag comprises utilizing a tool to engage and
lower the mesh bag into the storm water drainage system.
31. A method of removing heavy metals from storm water according to
claim 28, wherein said treatment material comprises a zeolite
material having an ion exchange capacity.
32. A method of removing heavy metals from storm water according to
claim 31, wherein said zeolite material having an ion exchange
capacity is selected from the group consisting of Chabazite and
Clinoptilolite.
33. A method of removing heavy metals from storm water according to
claim 28, further comprising a step of performing a maintenance
operation on the treatment material.
34. A method of removing heavy metals from storm water according to
claim 33, wherein said step of performing a maintenance operation
on the treatment material comprises removing the treatment material
and replacing it with new treatment material.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to systems and processes for
cleansing storm water, such as that which is created by storm
runoff from streets, highways, parking lots and other paved
surfaces into drainage systems in major urban areas.
[0003] 2. Description of the Related Technology
[0004] Storm water that is created by storm runoff in heavily
developed areas is typically channeled into storm drainage systems
that eventually drain into nearby streams, creeks, rivers or other
bodies of water. Unfortunately, paved surfaces that bear automobile
traffic typically become coated with significant pollutants such as
heavy metals and volatile organic compounds, both under normal
traffic conditions and in particular when motor vehicle accidents
occur. When normal rain or snowfall occurs, these pollutants tend
to be swept away with the runoff storm water and eventually lead to
contamination of the bodies of water that eventually receive them.
Such contamination has become a significant environmental issue in
many areas. In addition, a significant amount of debris such as
bottles and cans tends to be swept away by storm water runoff.
[0005] Systems exist for filtering storm water runoff that are
effective in removing debris from storm water and in removing
certain other pollutants, such as hydrocarbons. For example, U.S.
Pat. No. 6,080,307 discloses a storm drain insert that contains one
basket for the collection of debris as well as a canister that
contains a hydrophobic, compliant, oil-absorbent copolymer material
that is said to be effective in removing oil from the storm
water.
[0006] Unfortunately, prior to this invention no system or process
has been developed that is capable of removing heavy metals from
storm water in situ within a storm water drainage system.
Technology exists for removing heavy metals from storm water within
complex storm water treatment facilities, but not locally within
storm water drainage systems where such treatment facilities are
not present.
[0007] A need exists for an improved system and process for
processing storm water that is effective in removing heavy metals,
as well as hydrocarbons and other volatile organic compounds, from
the storm water in situ within a storm water drainage system.
SUMMARY OF THE INVENTION
[0008] Accordingly, it is an object of the invention to provide an
improved system and process for processing storm water that is
effective in removing heavy metals, as well as hydrocarbons and
other volatile organic compounds, from the storm water in situ
within a storm water drainage system.
[0009] In order to achieve the above and other objects of the
invention, a method of removing heavy metals from storm water
according to a first aspect of the invention comprises steps of
positioning a treatment system within a drainage space through
which storm water is designed to flow, the treatment system
comprising a process chamber in which a treatment material that is
capable of absorbing heavy metals from storm water is disposed, the
treatment system further comprising a first passageway for
admitting storm water from the drainage space into the process
chamber and a second passageway for permitting treated storm water
to return from the process chamber to the drainage space; and
permitting storm water to flow through the drainage space, whereby
it is at least partially treated by the treatment system.
[0010] According to a second aspect of the invention, a method of
retrofitting a storm water drainage system for the purpose of
reducing heavy metal contamination of storm water that may flow
therethrough, includes steps of reconfiguring a storm water
drainage system that has a drainage space through which storm water
is designed to flow by installing a treatment system, the treatment
system comprising a process chamber in which a treatment material
that is capable of absorbing heavy metals from storm water is
disposed, the treatment system further comprising a first
passageway for admitting storm water from the drainage space into
the process chamber and a second passageway for permitting treated
storm water to return from the process chamber to the drainage
space; and permitting storm water to flow through the retrofitted
storm water drainage system.
[0011] According to a third aspect of the invention, a system for
treating storm water in situ within a storm water drainage system
includes a process chamber; treatment material contained within the
process chamber, the treatment material being capable of absorbing
heavy metals from storm water; a first passageway for admitting
storm water from the storm water drainage system into the process
chamber; and a second passageway for permitting treated storm water
to return from the process chamber to the storm water drainage
system.
[0012] A method of removing heavy metals from storm water according
to a fourth aspect of the invention includes a step of introducing
into a storm water drainage system a treatment material that is
capable of absorbing heavy metals from storm water.
[0013] These and various other advantages and features of novelty
that characterize the invention are pointed out with particularity
in the claims annexed hereto and forming a part hereof. However,
for a better understanding of the invention, its advantages, and
the objects obtained by its use, reference should be made to the
drawings which form a further part hereof, and to the accompanying
descriptive matter, in which there is illustrated and described a
preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a diagrammatic view depicting a system according
to a first embodiment of the invention;
[0015] FIG. 2 is a front elevational view of one portion of the
system that is depicted in FIG. 1;
[0016] FIG. 3 is a top plan view of the portion of the system that
is depicted in FIG. 2;
[0017] FIG. 4 is a side elevational view of the portion of the
system that is shown in FIGS. 2 and 3;
[0018] FIG. 5 is a first diagrammatical view of a system that is
constructed according to a second embodiment of the invention;
[0019] FIG. 6 is a second diagrammatical view of the system that is
shown in FIG. 5;
[0020] FIG. 7 is a diagrammatical view of a system that is
constructed according to a third embodiment of the invention;
[0021] FIG. 8 is a diagrammatical view depicting an alternative
construction of one component of the system that is shown in FIG.
7;
[0022] FIG. 9 is a side elevational view of a mesh bag that is used
to deploy treatment material according to the preferred embodiment
of the invention; and
[0023] FIG. 10 is a side elevational view of a tool that is
preferably used according to the invention in order to deploy and
retrieve the mesh bag depicted in FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0024] Referring now to the drawings, wherein like reference
numerals designate corresponding structure throughout the views,
and referring in particular to FIG. 1, a system 10 according to a
first embodiment of the invention for treating storm water in situ
within a storm water drainage system that includes a storm grate 12
set within a frame rim 14 is constructed and arranged to process
inflowing storm water 16, as is shown diagrammatically in FIG. 1.
System 10 is further constructed so that during heavy storm water
flow conditions any excess flow 18 of storm water that is incapable
of being processed by the system 10 will be permitted to flow
through an overflow or bypass opening 40 into the storm water
drainage system, as will be described in greater detail below.
Bypass opening 40 is capable of handling a flow of at least 5000
gallons per minute. Storm water 20 that is processed by the system
10 will also flow into the storm water drainage system through a
pair of exit openings 38, as will also be described in greater
detail below.
[0025] As is further shown in FIG. 1, a process chamber 21 is
defined within a receptacle 22 that has a bottom surface 24 and a
plurality of side surfaces 26. Receptacle 22 is integral with a
metallic tray 30 that is mounted so as to depend downwardly from
the storm grate 12 and the connected frame rim 14. An upper portion
of tray 30 is shaped as a funnel 34 so as to ensure that storm
water passing through the storm grate 12 will be directed into the
tray 30. In order to avoid having standing water within the tray 30
for extended periods of time, a number of drain openings 31 may be
provided in a lower surface of the tray 30 to provide slow
drainage. The drain openings 31 may be covered by a spongelike
material to ensure that only a very slow flow of liquid is
permitted to pass therethrough.
[0026] As may be seen in FIGS. 1 and 4, a pair of openings 32 are
defined in oppositely facing side surfaces 26 of the receptacle 22
for permitting storm water 28 that is collected in a lower portion
of the tray 30 to enter into the process chamber 21, where it will
interact with treatment material 36 that is contained within the
process chamber 21. Treatment material 36 is preferably material
that is capable of absorbing heavy metals from storm water.
[0027] With respect to all of the embodiments of the invention that
will be described herein, the preferred active ingredient within
treatment material 36 is a zeolite that has an ion exchange
capacity. Zeolite is a porous crystal material composed mainly an
aluminum and silicon with other minerals such as potassium, calcium
and sodium, which are used as exchangeable cations. The individual
crystals bond together in long chains creating a lattice type
network of interconnected cavities, pores and open spaces which
provide sites for cation exchange and adsorption. As a filtering
media, zeolite will draw liquid runoff into its crystal structure
where it is adsorbed onto the large surface areas. Suspended solids
are effectively removed, and become physically entrapped or
encapsulated within these cavities and pores. The zeolite
effectively may function as a filter bed as well as a process
material for cation exchange and adsorption. Toxic metal ions in
the liquid displace the calcium, sodium or potassium cations in the
passageways and become strongly bonded to the numerous exchange
sites. The extreme molecular complexity also significantly reduces
the external surface area, which further limits the potential
mobility of the contaminants to leach back into the
environment.
[0028] Each zeolite mineral has a distinct ion exchange selectivity
and capacity. This process occurs when water molecules can pass
through the channels and pores allowing cations present in the
solution to be exchanged for cations in the structure. Several
factors must be considered in this process. These include solution
strength, pH, temperature and the presence of other competing
cations in the solution. These factors can affect both the ion
exchange selectivity and capacity of the specific zeolite mineral.
Chabazite and Clinoptilolite are two of the minerals in the zeolite
group that possess superior ion exchange capability. Chabazite is
the preferred zeolite material for use in the preferred embodiment
of the invention. However, the invention may be practiced using any
treatment material, zeolite or otherwise, that is capable of
absorbing heavy metals from storm water. This includes zeolites or
other materials that have been chemically enhanced to increase
their cation exchange capacity.
[0029] Referring again to FIG. 1, it will be seen that the space
defined by the tray 30 and the openings 32 together define a first
passageway for admitting storm water from the storm water drainage
system into the process chamber 21. Exit openings 38 that are
defined in an upper portion of the receptacle 22 define a second
passageway for permitting treated storm water to return from the
process chamber 21 to the storm water drainage system. Looking now
to FIG. 3, which is a top plan view of the system 10, it will be
seen that receptacle 22 includes a top cover 42 in which is defined
an access opening 46 through which the treatment material 36 may be
removed and replaced with new treatment material periodically. A
removable media access cover 44 is removably mounted on the top
cover 42 to prevent debris from entering the process chamber 21
during normal operating conditions. Referring briefly to FIGS. 9
and 10, preferably for all embodiments of the invention the
treatment material 36 is provided within one or more mesh bags 130
that are fabricated from a mesh material 132 so that the treatment
material 36 may be conveniently positioned within the process
chamber 21 and later removed. As FIG. 9 shows, engagement structure
134 is preferably provided on each of the mesh bags 130 for
permitting retrieval and lifting of the mesh bags 130 during
deployment and retrieval. In the illustrated embodiment, engagement
structure 134 is styled as a loop 136. Alternatively, engagement
structure 134 may be anyone of a number of possible configurations,
such as a hook, a magnet, a steel plate, a hole, or any other
structure that may be engaged by a remote tool. FIG. 10 depicts a
tool 138 that is used in the preferred embodiment of the invention
to deploy and retrieve the mesh bag 130 during installation and
maintenance of the system. Tool 138 includes a handle 140 and a
hook 142 that is constructed and arranged to be compatible with the
engagement structure 134. Specifically, hook 142 is size and shaped
so as to be able to conveniently fit within the loop 136 that is
attached to the mesh bag 130.
[0030] Alternatively, the treatment material 36 may be deployed
loosely within the process chamber 21 where it may be removed
periodically using vacuum technology.
[0031] Referring now to FIGS. 5 and 6, a system 50 for treating
storm water in situ within a storm water drainage system according
to a second embodiment of the invention includes a process chamber
60 that is defined within a vault 56. A first passageway 58 for
admitting storm water from the storm water drainage system into the
process chamber 60 is in this embodiment in communication with a
first storm water conduit 52, while a second passageway 62 for
permitting treated storm water to return from the process chamber
60 to the storm water drainage system is in communication with a
second storm water conduit 54. As is best shown in FIG. 6, a filter
64 that is preferably constructed of a metallic screen or mesh
material is positioned within the first passageway 58 for
permitting debris from entering the process chamber 60. First
passageway 58 is separated from the process chamber 60 by a first
baffle 72 that extends downwardly from a top wall 73 of the vault
56, terminating at the filter 64. As is shown diagrammatically in
FIGS. 5 and 6, debris 66 is kept within the first passageway 58 by
the filter 64, with sediment material 68 such as sand tending to
collect at the bottom of the vault 56 within the first passageway
58 while oily material and other material that will tend to float
will collect in an upper portion of the first passageway 58 that is
elevated with respect to the downwardmost terminus of the first
baffle 72. This will help ensure that oily material that might
otherwise pass through the filter 64 will remain collected within
the first passageway 58 instead of being driven into the process
chamber 60.
[0032] To provide a bypass capable of handling 5000 gallons per
minute in the event of heavy flow conditions, a window 77 is
defined in an upper portion of the first baffle 72. This provides a
bypass route through the upper portion of the process chamber 60
and for the through the bypass 78 into the second passageway 62.
Additionally, at least one slow drain port 75 is defined in the
bottom wall of the vault 56 to prevent water from standing within
the vault 56 for a prolonged period of time.
[0033] As is shown in FIG. 6, the treatment material 74, which is
preferably contained within mesh bags as described above with
regard to the previously described embodiment, is kept positioned
within the process chamber 60 by a number of positioning baffles
82. In addition, a baffle 80 is provided in order to separate the
process chamber 60 from the second passageway 62. As is best shown
in FIG. 6, baffle 80 terminates at its lower end a predetermined
distance from the bottom of the vault 56 so as to define the space
for the process storm water to escape from the process chamber 60
into the second passageway 62 during normal operating conditions. A
retention screen 76 is preferably provided within this space for
preventing the treatment material 74 from escaping into the second
passageway 62. During extreme operating conditions, when the flow
of storm water through the conduit 52, 54 exceeds the capacity of
the system 50 to process the storm water, excess storm water within
the process chamber 60 will be permitted to escape into the second
passageway 62 through a bypass opening 78 that is defined between
the top edge of the baffle 80 and the top wall 73 of the vault
56.
[0034] Referring again to FIG. 6, it will be seen that a first
access opening 84 is defined in the top wall 73 of the vault 56 for
permitting access to the process chamber 60 in order to position
treatment material 74 within the process chamber 60 and to
subsequently remove the treatment material 74 and replace it with
new treatment material 74. A removable cover 85 is removably
mounted on the first access opening 84. Similarly, a second access
opening 86 is defined in the top wall 73 of the vault 56 for
permitting debris 66 to be removed from the first passageway 58. A
cover 87 is removably mounted to the top wall 73 in order to
selectively cover and expose the second access opening 86.
[0035] A system 90 for treating storm water according to a third
embodiment of the invention is depicted in FIG. 7. In this
embodiment, the system 90 is mounted within a drainage chamber 92
that is constructed and arranged to induce storm water to be
absorbed into the surrounding soil 94. Storm water enters the
drainage chamber 92 via an opening 96 that is covered by a grate
98. Storm water flowing through the opening 96 is directed into a
vertical conduit 100 by a funnel structure 101 that is positioned a
predetermined distance beneath the opening 96. Stabilizer arms 103
are provided to ensure that the vertical conduit 100 stays properly
positioned during use. The predetermined difference between the
funnel structure 101 and the vertical conduit 100 provides for a
bypass opening directly into the drainage chamber 92 that is
capable of handling at least 5000 gallons per minute. An upper
portion of the conduit 100 defines a first passageway for admitting
storm water from the storm water drainage system into a process
chamber 110 that is defined within a lower portion 104 of the
vertical conduit 100. As is further shown in FIG. 7, a plurality of
drainage openings 106 are defined in the lowermost end of the
vertical conduit 100 for permitting treated storm water to flow
from the process chamber 110 into the drainage chamber 92, where
the storm water can be absorbed into the environment. Preferably,
the treatment material 111 is positioned loosely within the lower
portion 104 of the vertical conduit 100 and is of a size and
granularity so that the individual granules of the treatment
material 111 will not pass through the drainage openings 106. In
order to maximize the surface area of the treatment material 111
that is present within the process chamber 110, larger granules of
treatment material 111 may be deposited at the bottom of the
vertical conduit 100 nearby to the drainage openings 106, while
smaller particles or granules of treatment material 111 may be
positioned above this layer of larger particles or granules.
[0036] An oil separation tube 105 provides an exit for storm water
that collects during flood conditions high enough within the
vertical conduit 100 to flow into the oil separation tube and out
of the vertical conduit 100. As is shown in FIG. 7, oil separation
tube 105 enters the upper portion of the vertical conduit 100 in a
radial direction and bends downwardly within the vertical conduit
100. During flood conditions, organic elements such as oil will
tend to float on top of the water and will thus tend to be retained
within the vertical conduit 100 for processing.
[0037] Filter structure is preferably provided for preventing
debris from entering the process chamber 110 from the upper portion
102 of the vertical conduit 100. In the preferred embodiment, this
filter structure is embodied as a debris basket 108 that is
accessible and removable by a long pole that may be extended
downwardly into the upper portion 102 of the vertical conduit 100
via the opening 96 after the grate 98 has been removed. In an
alternative embodiment, shown in FIG. 8, a filter arrangement 120
is provided wherein a separate debris exit 124 is defined in the
conduit 100, and a debris grill 122 is positioned within the
vertical conduit 100 at an angle with respect to the longitudinal
axis of the conduit 100 in order to direct debris out of the
vertical conduit 100 into the debris exit 124 while permitting
storm water to flow downwardly into the process chamber 110. The
advantage of this embodiment of the invention is that it is self
maintaining, obviating the need to periodically service the system
90 to remove collected debris.
[0038] A system for treating storm water according to any of the
previously described embodiment may be installed as original
equipment on a storm water drainage system or, must advantageously,
may be retrofitted onto an existing storm water drainage system in
order to mitigate the environmental effects of contaminated storm
water. Within the scope of the invention, as an alternative
embodiment, the treatment material may be introduced directly into
the system with minimal or no containment. For example, the
treatment material may be simply contained within the mesh bag 130
and deployed in a drainage system that has no process chamber or in
a drainage system that has a space that is designed for purposes
other than the present invention.
[0039] It is to be understood, however, that even though numerous
characteristics and advantages of the present invention have been
set forth in the foregoing description, together with details of
the structure and function of the invention, the disclosure is
illustrative only, and changes may be made in detail, especially in
matters of shape, size and arrangement of parts within the
principles of the invention to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *