U.S. patent application number 12/477015 was filed with the patent office on 2010-12-02 for rainwater recovery and treatment system.
This patent application is currently assigned to Waterdogs Water Recovery, LLC. Invention is credited to Timothy Joseph Baldwin, Kevin C. Eberle.
Application Number | 20100300544 12/477015 |
Document ID | / |
Family ID | 43218852 |
Filed Date | 2010-12-02 |
United States Patent
Application |
20100300544 |
Kind Code |
A1 |
Baldwin; Timothy Joseph ; et
al. |
December 2, 2010 |
RAINWATER RECOVERY AND TREATMENT SYSTEM
Abstract
Embodiments of the invention relate to systems and methods for
the harvesting and treatment of rainwater for secondary use within
buildings. Rainwater is harvested utilizing a rainwater capturing
device and stored in a cistern prior to treatment until a demand
for secondary use is made. The rainwater may be combined with
reclaimed water from a water treatment plant. Once a demand for
secondary use is made, the water is subjected to treatment as it
travels to the point of use. Treatment includes neutralizing the pH
of the rainwater, filtering the rainwater to remove particulate
matter, irradiating the rainwater with ultraviolet light, and
introducing a chlorine solution into the rainwater.
Inventors: |
Baldwin; Timothy Joseph;
(Holly Springs, NC) ; Eberle; Kevin C.; (Cary,
NC) |
Correspondence
Address: |
MOORE & VAN ALLEN PLLC
P.O. BOX 13706
Research Triangle Park
NC
27709
US
|
Assignee: |
Waterdogs Water Recovery,
LLC
Charlotte
NC
|
Family ID: |
43218852 |
Appl. No.: |
12/477015 |
Filed: |
June 2, 2009 |
Current U.S.
Class: |
137/1 ;
137/560 |
Current CPC
Class: |
E03B 3/03 20130101; C02F
1/44 20130101; Y02A 20/108 20180101; C02F 2209/006 20130101; C02F
1/66 20130101; Y02A 20/00 20180101; C02F 1/008 20130101; E03B
2001/047 20130101; Y02A 20/106 20180101; C02F 1/32 20130101; E03B
7/074 20130101; C02F 1/76 20130101; Y10T 137/0318 20150401; C02F
9/00 20130101; C02F 2103/001 20130101; E03B 1/04 20130101; Y10T
137/8376 20150401 |
Class at
Publication: |
137/1 ;
137/560 |
International
Class: |
E03C 1/00 20060101
E03C001/00 |
Claims
1. A rainwater recovery and treatment system for secondary use, the
system comprising: a rainwater capturing device configured to
capture falling rainwater; a pump station configured to receive the
rainwater captured by the rainwater capturing device; a pH
adjustment device configured to neutralize the pH of the rainwater;
a filtration device configured to remove particulate matter from
the rainwater; an ultraviolet disinfection device configured to
irradiate the rainwater with ultraviolet light; and a chemical
disinfection device configured to introduce chlorine into the
rainwater.
2. The system of claim 1, further comprising: a rainwater storage
device configured to store water and connected via a first conduit
to the rainwater capturing device and via a second conduit to the
pump station, wherein the rainwater captured by the rainwater
capturing device flows through the first conduit into the rainwater
storage device for storage and then flows through the second
conduit into the pump station.
3. The system of claim 2, wherein the rainwater storage device is a
cistern.
4. The system of claim 2, wherein the rainwater storage device is
buried underground and comprises an impervious liner and stone
fill.
5. The system of claim 2, wherein the rainwater storage device is
integrated into another water management system.
6. The system of claim 1, wherein the rainwater capturing device is
located on the roof of a building.
7. The system of claim 1, wherein the rainwater capturing device
comprises the roof of a building.
8. The system of claim 1, wherein the pump station is configured to
utilize at least one level measuring device and a pump station
control system to maintain the level of water held by the pump
station within a particular range of levels.
9. The system of claim 1, further comprising: a pressurizing device
configured to pressurize the rainwater prior to it passing through
any of the pH adjustment device, the filtration device, the
ultraviolet disinfection device, or the chemical disinfection
device.
10. The system of claim 9, wherein the pressurizing device
comprises at least one hydro-pneumatic tank.
11. The system of claim 1, wherein the pH adjustment device
comprises at least one calcite filter.
12. The system of claim 1, wherein the filtration device comprises
at least one of the following: a disc filter, a cartridge filter,
or a membrane filter.
13. The system of claim 1, wherein the chemical disinfection device
comprises an on-site hypochlorite generating system or a tablet
chlorinator.
14. The system of claim 1, further comprising a chlorine sensor
configured to measure the level of chlorine present in water and a
master control system configured to receive transmissions from the
chlorine sensor and interface with the chemical disinfection
device, wherein the master control system is configured to cause
the chemical disinfection device to adjust the amount of chlorine
introduced into the water based on a transmission from the chlorine
sensor.
15. A water recovery and treatment system for secondary use, the
system comprising: a rainwater storage device configured to store
rainwater; a pump station configured to receive rainwater from the
rainwater storage device and reclaimed water, wherein the pump
station is further configured to receive reclaimed water only in
the event the pump station is unsuccessful in receiving a
predetermined volume of rainwater from the rainwater storage
device; and a water treatment system.
16. The system of claim 15, wherein the rainwater storage device is
a cistern.
17. The system of claim 15, wherein the rainwater storage device is
buried underground and is comprised of an impervious liner and
stone fill.
18. The system of claim 15, wherein the rainwater storage device is
integrated into another water management system.
19. The system of claim 15, wherein the pump station is configured
to utilize a level measuring device and a pump station control
system to maintain the level of water held by the pump station
within a particular range of levels.
20. The system of claim 19, wherein the pump station control system
is configured to receive signals from the level measuring device
that cause the pump station to receive rainwater from the rainwater
storage device.
21. The system of claim 20, wherein the pump station control system
is configured to cause the pump station to receive reclaimed water
in the event the pump station is unsuccessful in obtaining a
predetermined volume of rainwater from the rainwater storage
device.
22. The system of claim 15, wherein the water treatment system
comprises a pH adjustment device configured to neutralize the pH of
water; a filtration device configured to remove particulate matter
from water; an ultraviolet disinfection device configured to
irradiate water with ultraviolet light; and a chemical disinfection
device configured to introduce a chlorine into water.
23. The system of claim 22, further comprising: a pressurizing
device configured to pressurize water prior to it passing through
any of the pH adjustment device, the filtration device, the
ultraviolet disinfection device, or the chemical disinfection
device.
24. The system of claim 23, wherein the pressurizing device
comprises at least one hydro-pneumatic pump.
25. The system of claim 22, wherein the pH adjustment device
comprises at least one calcite filter.
26. The system of claim 22, wherein the filtration device comprises
at least one of the following: a disc filter, a cartridge filter,
or a membrane filter.
27. The system of claim 22, wherein the chemical disinfection
device comprises an on-site hypochlorite generating system or a
tablet chlorinator.
28. The system of claim 22, further comprising a chlorine sensor
configured to measure the level of chlorine present in water and a
master control system configured to receive signals from the
chlorine sensor and interface with the chemical disinfection
device, wherein the master control system is configured to cause
the chemical disinfection device to adjust the amount of chlorine
introduced into the water based on a signal from the chlorine
sensor.
29. A method of recovering and treating rainwater for secondary use
within a building, the method comprising: capturing rainwater
utilizing a rainwater capturing device; storing the rainwater in a
rainwater storage device; neutralizing the pH of the rainwater;
filtering the rainwater to remove particulate matter; irradiating
the rainwater with ultraviolet light; and introducing a chlorine
solution into the rainwater.
30. The method of claim 28, further comprising, obtaining reclaimed
water; and combining the reclaimed water with the rainwater.
31. The method of claim 29, wherein the reclaimed water is obtained
from a water treatment plant.
32. The method of claim 29, wherein the reclaimed water is combined
with the rainwater prior to said neutralizing, filtering,
irradiating, and introducing steps.
33. The method of claim 31, wherein the reclaimed water and the
rainwater are combined in a pump station.
34. The method of claim 28, wherein the rainwater capturing device
comprises a roof of a building.
35. The method of claim 28, wherein the rainwater storage device is
buried underground, and comprises an impervious liner and stone
fill.
36. A product comprising water produced by a method comprising:
capturing rainwater utilizing a rainwater capturing device; storing
the rainwater in a rainwater storage device; neutralizing the pH of
the rainwater; filtering the rainwater to remove particulate
matter; irradiating the rainwater with ultraviolet light; and
introducing a chlorine solution into the rainwater.
37. A system for the supply of water for secondary use, the system
comprising: a building comprising a rainwater capturing device and
a rainwater treatment unit; a water storage device comprising a
cistern and a pump station, wherein the water storage device is
configured to receive rainwater from the rainwater capturing device
and reclaimed water, combine the rainwater and the reclaimed water,
and transfer the combined rainwater and reclaimed water to the
building for treatment by the water treatment system.
38. The system of claim 36, wherein the water treatment system
comprises: a pH adjustment device configured to neutralize the pH
of acidic water; a filtration device configured to remove
particulate matter; an ultraviolet disinfection device configured
to irradiate water with ultraviolet light; and a chemical
disinfection device configured to introduce a chlorine solution
into water.
Description
FIELD
[0001] In general, embodiments of the invention relate to systems
and methods for the harvesting and treatment of rainwater.
BACKGROUND
[0002] In today's world, water is voraciously consumed with little
thought to the devastating effects that result from such
uncontrolled consumption. The excessive and inefficient use of
water by the world's population does not reflect an adequate
understanding of the fact that the amount of fresh water in this
world is limited. No longer problems exclusively belonging to third
world countries, lack of water supply and flawed water
infrastructure plague communities across the globe. It is
anticipated that these challenges will only become worse as the
world's population grows. Increased demand for water places
additional stress on water supplies and distribution systems,
threatening both human health and the environment. Indeed, lower
water levels due to depleting reservoirs and groundwater can
contribute to higher concentrations of natural or human pollutants.
Furthermore, it takes a considerable amount of energy to deliver
and treat the water that we use everyday.
[0003] By using water more efficiently, individuals and communities
can preserve water supplies for future generations, minimize the
effects of droughts, save money, and protect the environment.
Indeed, reducing the consumption of water from public water
supplies reduces the energy required to supply and treat the water,
which counters climate change and other threats to our environment.
Moreover, consumers can save significant amounts of money that
would otherwise be spent on water obtained from public water
supplies. However, despite the fact that many are aware of the
downfalls of excessive consumption of water and the benefits
provided by adopting efficient behaviors with regard to water use,
water conserving techniques are generally not implemented in favor
of continuing to use outdated systems and methodologies that
needlessly waste fresh water from our supplies and reservoirs. For
example, substantial amounts of potable water are consumed in the
course of uses that do not, in fact, require potable water, such as
flushing toilets. In sum, the consumption of water from public
supplies needs to be drastically reduced, and realistic and
economical solutions that serve this goal are required.
SUMMARY OF EMBODIMENTS OF THE INVENTION
[0004] Embodiments of the present invention relate to systems and
methods for the harvesting and treatment of rainwater for secondary
use. More particularly some embodiments of the invention provide a
rainwater recovery and treatment system for secondary use
comprising the following elements: a rainwater capturing device
configured to capture falling rainwater, a pump station configured
to receive the rainwater captured by the rainwater capturing
device, a pH adjustment device configured to neutralize the pH of
the rainwater, a filtration device configured to remove particulate
matter from the rainwater, an ultraviolet disinfection device
configured to irradiate the rainwater with ultraviolet light, and a
chemical disinfection device configured to introduce chlorine into
the rainwater.
[0005] The system may further comprise a rainwater storage device
configured to store water and connected via a first conduit to the
rainwater capturing device and via a second conduit to the pump
station, wherein the rainwater captured by the rainwater capturing
device flows through the first conduit into the rainwater storage
device for storage and then flows through the second conduit into
the pump station.
[0006] In some embodiments, the rainwater storage device is a
cistern. According to one embodiment, the rainwater storage device
is buried underground and comprises an impervious liner and stone
fill. In one embodiment, the rainwater storage device is integrated
into another water management system. With regard to the rainwater
capturing device, it may be located on the roof of a building, or
even comprise the roof of a building.
[0007] In some embodiments, the pump station is configured to
utilize at least one level measuring device and a pump station
control system to maintain the level of water held by the pump
station within a particular range of levels.
[0008] The system may also include a pressurizing device configured
to pressurize the rainwater prior to it passing through any of the
pH adjustment device, the filtration device, the ultraviolet
disinfection device, or the chemical disinfection device. The
pressurizing device may comprise a hydro-pneumatic tank. The pH
adjustment device may comprise at least one calcite filter. In some
embodiments, the filtration device comprises at least one of the
following: a disc filter, a cartridge filter, or a membrane filter.
According to some embodiments, the chemical disinfection device
comprises an on-site hypochlorite generating system or a tablet
chlorinator.
[0009] The system may further comprise a chlorine sensor configured
to measure the level of chlorine present in water and a master
control system configured to receive transmissions from the
chlorine sensor and interface with the chemical disinfection
device, wherein the master control system is configured to cause
the chemical disinfection device to adjust the amount of chlorine
introduced into the water based on a transmission from the chlorine
sensor.
[0010] According to other embodiments of the invention, a water
recovery and treatment system for secondary use is provided, the
system comprising a rainwater storage device configured to store
rainwater, a pump station configured to receive rainwater from the
rainwater storage device and reclaimed water, wherein the pump
station is further configured to receive reclaimed water only in
the event the pump station is unsuccessful in receiving a
predetermined volume of rainwater from the rainwater storage
device, and a water treatment system.
[0011] In some embodiments, the rainwater storage device is a
cistern. According to some embodiments, the rainwater storage
device is buried underground and is comprised of an impervious
liner and stone fill. The rainwater storage device may be
integrated into another water management system.
[0012] According to some embodiments, the pump station is
configured to utilize a level measuring device and a pump station
control system to maintain the level of water held by the pump
station within a particular range of levels. In some embodiments,
the pump station control system is configured to receive signals
from the level measuring device that cause the pump station to
receive rainwater from the rainwater storage device. Indeed, the
pump station control system may be configured to cause the pump
station to receive reclaimed water in the event the pump station is
unsuccessful in obtaining a predetermined volume of rainwater from
the rainwater storage device.
[0013] In some embodiments, the water treatment system comprises a
pH adjustment device configured to neutralize the pH of water, a
filtration device configured to remove particulate matter from
water, an ultraviolet disinfection device configured to irradiate
water with ultraviolet light, and a chemical disinfection device
configured to introduce a chlorine into water. The system may
further include a pressurizing device configured to pressurize
water prior to it passing through any of the pH adjustment device,
the filtration device, the ultraviolet disinfection device, or the
chemical disinfection device. In some embodiments, the pressurizing
device comprises at least one hydro-pneumatic pump. In some
embodiments, the pH adjustment device comprises at least one
calcite filter. According to some embodiments, the filtration
device comprises at least one of the following: a disc filter, a
cartridge filter, or a membrane filter. In some embodiments, the
chemical disinfection device comprises an on-site hypochlorite
generating system or a tablet chlorinator.
[0014] The system may further comprise a chlorine sensor configured
to measure the level of chlorine present in water and a master
control system configured to receive signals from the chlorine
sensor and interface with the chemical disinfection device, wherein
the master control system is configured to cause the chemical
disinfection device to adjust the amount of chlorine introduced
into the water based on a signal from the chlorine sensor.
[0015] According to other embodiments of the present invention, a
method of recovering and treating rainwater for secondary use
within a building is provided, the method comprising: capturing
rainwater utilizing a rainwater capturing device, storing the
rainwater in a rainwater storage device, neutralizing the pH of the
rainwater, filtering the rainwater to remove particulate matter,
irradiating the rainwater with ultraviolet light, and introducing a
chlorine solution into the rainwater. The method may further
include obtaining reclaimed water and combining the reclaimed water
with the rainwater. In some embodiments, the reclaimed water is
obtained from a water treatment plant. According to some
embodiments, the reclaimed water is combined with the rainwater
prior to said neutralizing, filtering, irradiating, and introducing
steps. In some embodiments, the reclaimed water and the rainwater
are combined in a pump station.
[0016] According to some embodiments, the rainwater capturing
device comprises a roof of a building. With regard to the rainwater
storage device, it may be buried underground, and comprised of an
impervious liner and stone fill.
[0017] Certain embodiments of the present invention provide a
product comprising water produced by a method comprising: capturing
rainwater utilizing a rainwater capturing device, storing the
rainwater in a rainwater storage device, neutralizing the pH of the
rainwater, filtering the rainwater to remove particulate matter,
irradiating the rainwater with ultraviolet light, and introducing a
chlorine solution into the rainwater.
[0018] Still other embodiments of the present invention provide a
system for the supply of water for secondary use, the system
comprising: a building comprising a rainwater capturing device and
a rainwater treatment unit, a water storage device comprising a
cistern and a pump station, wherein the water storage device is
configured to receive rainwater from the rainwater capturing device
and reclaimed water, combine the rainwater and the reclaimed water,
and transfer the combined rainwater and reclaimed water to the
building for treatment by the water treatment system. In some
embodiments, the water treatment system comprises: a pH adjustment
device configured to neutralize the pH of acidic water, a
filtration device configured to remove particulate matter, an
ultraviolet disinfection device configured to irradiate water with
ultraviolet light, and a chemical disinfection device configured to
introduce a chlorine solution into water.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Having thus described embodiments of the invention in
general terms, reference will now be made to the accompanying
drawings:
[0020] FIG. 1 is a diagram illustrating a rainwater recovery system
according to one embodiment of the present invention;
[0021] FIG. 2 is a diagram illustrating a rainwater treatment
system according to one embodiment of the present invention;
[0022] FIG. 3 is a diagram illustrating a cistern system according
to one embodiment of the present invention;
[0023] FIG. 4 is a flow chart illustrating an exemplary method of
recovering and managing rainwater in anticipation of secondary use
in buildings, according to one embodiment of the invention; and
[0024] FIG. 5 is a flow chart illustrating an exemplary method of
treating rainwater for secondary use in buildings, according to one
embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0025] As discussed above, there is a need to reduce the
consumption of fresh water from public water supplies. To be
certain, this goal may be achieved by an overall reduction in water
use. On the other hand, and as reflected by the present invention,
this goal may also be achieved without reducing water use, but by
utilizing recovered rainwater or a combination of rainwater and
treated reclaimed water as a substitute for water that would
otherwise come from the public supplies. As used herein, the term
"reclaimed water" means water treated to reuse/reclaimed water
standards (i.e. reclaimed water from a wastewater treatment plant
that produces effluent that may be classified as reclaimed or reuse
water). The present invention reduces a building's consumption of
water from public water supplies by eradicating the use of that
water for secondary uses within the building, instead utilizing
rainwater or a combination of rainwater and reclaimed water for
such secondary uses. As used herein, the term "secondary use" means
any use for which potable water is not required, such as toilet
flushing, use in air conditioning systems, fire suppression etc.
Therefore, according to some embodiments, once the invention is
implemented, the water that runs in the sinks of the building is
fresh water supplied by the city or other customary water source,
while the water that runs in the toilets is rainwater or a
combination of rainwater and reclaimed water that is treated and
supplied by the systems of the present invention.
[0026] The present invention operates under the assumption that
secondary uses do not require water having the highest level of
purification, as is required for primary uses. By continually
expending potable water for secondary uses, for example, in the
process of flushing toilets, buildings and communities are wasting
an opportunity to cut costs and decrease their carbon footprint.
The present invention seeks to alter the status quo and capitalize
on this opportunity by dividing the uses of water within a building
into primary or secondary uses, and causing the supply of water of
varying purification levels from distinct sources depending upon
the use. Specifically, potable water from the building's
traditional water source is supplied to the points of use
corresponding to primary uses, while water from the recovery and
treatment system of the present invention is supplied to the points
of use corresponding to secondary use (i.e. toilets).
[0027] This bifurcation of the water infrastructure of a building
advantageously allows the building to consume substantially less
water from its conventional source, which is in many cases the
public fresh water supply. Indeed, by eliminating a significant
source of demand for water from public supplies (the demand for
secondary uses), the present invention conserves potable water that
would otherwise be needlessly consumed by secondary uses. This
benefits the environment by preserving limited water resources and
decreasing the amount of energy that must be expended to treat and
deliver water from the public supply. Moreover, it reduces the
financial expenses associated with the acquisition of water from
the public supply.
[0028] With regard to how the present invention operates in
practice, the present invention provides for the harvesting and
storage of rainwater, the optional combination of this rainwater
with reclaimed water, and the treatment of the combined water in
anticipation of secondary use in a building. These processes and
the systems utilized to effectuate these processes will be
discussed in detail below. It should be noted that the use of
rainwater is preferred to the use of reclaimed water, inasmuch as
using rainwater is not only free, but also a more environmentally
friendly practice. Indeed, reclaimed water is more environmentally
friendly than fresh water because it is recycled, since it must be
treated at a plant and delivered to the building, it has a number
of the same energy costs as fresh water from public supplies. It
should also be noted that the systems and methods of the present
invention may be implemented on any scale, from single family
houses to large commercial buildings to entire communities. The
only requirement is that the plumbing of the house, building,
community, etc. be configured such that points of use corresponding
to secondary uses are connected directly or indirectly to the
system of the present invention, rather than connected to the
traditional water supply. Thus, when a demand for water is made for
secondary use, the treated rainwater or the treated combination of
rainwater and reclaimed water of the present invention is supplied,
rather than the fresh water from the public water supply.
[0029] Embodiments of the present invention now will be described
more fully hereinafter with reference to the accompanying drawings,
in which some, but not all, embodiments of the invention are shown.
Indeed, the invention may be embodied in many different forms and
should not be construed as limited to the embodiments set forth
herein; rather, these embodiments are provided so that this
disclosure will satisfy applicable legal requirements. Like numbers
refer to like elements throughout.
[0030] FIG. 1 is a diagram that illustrates a rainwater recovery
system 100 according to a preferred embodiment of the present
invention. FIG. 2 is a diagram that illustrates a rainwater
treatment system 200 according to a preferred embodiment of the
present invention. Together, FIGS. 1 and 2 illustrate a rainwater
recovery and treatment system in accordance with a preferred
embodiment of the invention. The rainwater recovery system 100 and
rainwater treatment system 200 are illustrated in separate figures
for purposes of clarity and convenience only, and it should be
understood that the subject matter presented in each figure may be
combined to provide a complete rainwater recovery and treatment
system according to some embodiments of the invention.
[0031] As shown in FIG. 1, at least one rainwater capturing device
110 is provided. In some embodiments, the rainwater capturing
devices 110 is placed on or incorporated into the roof of a
building in which the water treated by the rainwater treatment
system 200 will be used. The roof itself may be the rainwater
capturing device 110. In other embodiments, the rainwater capturing
device 110 may be located on the roofs of other buildings and in
other locations in addition to or instead of the roof of a building
in which the water treated by the rainwater system 200 will be
used. In different embodiments, the rainwater capturing device 110
is an open top tank, a sloped sheet made of metal, concrete or
other material, a membrane or liner configured to collect
rainwater, a gutter, or any combination of the foregoing. The
rainwater capturing device 110, according to some embodiments, is
configured such that rainwater captured thereby may be transferred
to a rainwater storage device, such as the cistern 120 shown in
FIG. 1, that is configured to store the rainwater until there is a
demand for it. It should be understood that such a rainwater
storage device is optional.
[0032] In some embodiments, and as illustrated in FIG. 1, the
cistern 120 is located in a remote location in relation to the
rainwater capturing device 110. In such embodiments, storage
conduits 112 such as downspouts and pipes connect the rainwater
capturing device 110 and the cistern 120 such that the rainwater
captured by the rainwater capturing device 110 may travel to the
cistern 120 through the storage conduits 112. In other embodiments,
the cistern 120 may be directly attached to the rainwater capturing
device 110. In still other embodiments, the cistern 120 and the
rainwater capturing device 110 may be one and the same. Depending
on the configuration of the rainwater capturing device 110 and the
cistern 120, especially with regard to the elevation drop from the
rainwater capturing device 110 to the cistern 120, a pressurizing
device such as a pump may be provided to instigate the flow of
rainwater from the rainwater capturing device 110 to the cistern
120. Alternatively, the rainwater capturing device 110 and the
cistern 120 may be configured such that there is a sufficient
elevation drop between them to allow hydrostatic pressure to cause
the flow of rainwater from the rainwater capturing device 110 to
the cistern 120. According to some embodiments of the present
invention, the cistern 120 may be integrated into other water
management systems separate from the rainwater recovery and
treatment system that is the subject of embodiments of the present
invention. For example, and as illustrated in FIG. 3, the cistern
120 may be integrated into a stormwater management system.
[0033] FIG. 3 provides a schematic drawing of an exemplary cistern
120 integrated with a stormwater management system according to
some embodiments of the present invention. As shown in FIG. 3,
concrete box culverts 310 are provided for detaining stormwater
other than rainfall, for example, surface runoff. In some
embodiments, the culverts 310 are buried beneath the ground and are
encapsulated by a bed of washed stone fill 320. The empty volume
within the bed of washed stone fill 320 (created by the space
between stones) may be filled with the rainwater captured by the
rainwater capturing device 110 such that the bed of washed stone
fill 320 is the cistern 120 that stores the rainwater. An
impervious liner 312 separates the bed of washed stone fill 320
from the surrounding ground to contain the rainwater and prevent
exposure of the rainwater to contaminants that could be introduced
by the surrounding ground. According to some embodiments, attached
to the bed of washed stone fill 320 are two conduits--an incoming
conduit 322 for carrying rainwater captured by the rainwater
capturing apparatus 110 into the bed of washed stone fill 320 and
an outgoing conduit 324 for carrying the rainwater stored in the
bed of washed stone fill 320 out of the bed of washed stone fill
320 in anticipation of treatment and, ultimately, use. In some
embodiments, the incoming conduit 322 and the outgoing conduit 324
are one and the same.
[0034] The foregoing example of a cistern 120 in accordance with
some embodiments of the invention should not be construed to limit
the type of cistern that may be utilized in embodiments of the
present invention. Indeed, those skilled in the art will be capable
of designing and implementing the cistern 120 in countless ways
within the scope of the present invention, depending upon the
particular environment in which the rainwater recovery and
treatment system is being installed. For instance, the cistern 120
may take the form of an above-ground open top or closed top storage
tank, a buried storage tank, or a lined reservoir or lake. The
foregoing example was provided because it demonstrates one way in
which the cistern 120 may be advantageously and seamlessly
incorporated into a larger water management environment.
[0035] In the event a stormwater detention system and a rainwater
recovery system are being constructed at the same time, by
integrating the cistern 120 with stormwater storage devices such as
the culverts 310, the work and expense associated with the
construction of the stormwater and rainwater systems may be reduced
or minimized. In that regard, in order to bury the culverts 310
under ground, a volume of earth much larger than the culverts 310
themselves must be excavated, and in some cases, removed and
relocated to a remote location. In such instances, rather than
hauling in compact fill to fill the excavated area surrounding the
culverts 310 and constructing a separate cistern 120 for rainwater,
it is advantageous to use the excavated area surrounding the
culverts 310 as the cistern 120. Moreover, burying the cistern 120
underground is advantageous as it preserves space above ground and
increases the elevation difference between the cistern 120 and the
rainwater capturing device 110, which aids the travel of the
rainwater from the rainwater capturing device 110 to the cistern
120. As discussed above, the cistern 120 may be created by
utilizing an impervious liner 312 and washed stone fill of a
minimum particulate size.
[0036] Referring again to FIG. 1, in some embodiments, a pump
station 130 having a wet well therein is provided that is
configured to receive rainwater from the cistern 120. The pump
station 130 has a first incoming conduit 131 that is connected to
the cistern 120, either directly or indirectly, and serves as a
conduit for the rainwater arriving at the pump station 130 from the
cistern 120. The pump station 130 may also have, according to some
embodiments, a second incoming conduit 132 that serves as a conduit
for reclaimed water arriving at the pump station 130 from a
wastewater treatment plant 150. It should be understood that the
second incoming conduit 132 bringing reclaimed water to the pump
station 130 is optional, and in some embodiments the pump station
130 shall be configured such that the only water it receives is
rainwater from the cistern 120. In some embodiments, the pump
station 130 is configured to hold water that will be transferred to
the rainwater treatment system 200 upon demand. Therefore,
according to some embodiments, the pump station 130 is equipped
with various pumps 133, level measuring devices 134, and a pump
station control panel 135 that ensure that the wet well of the pump
station 130 continually holds an adequate amount of water to meet
the requirements at the point-of-use.
[0037] In some embodiments, the pump station control panel 135 is
configured to receive indications from the level measuring devices
134 and operate the pumps 133 to pump water into the pump station
from either the cistern 120 (through the first incoming conduit
131) or the wastewater treatment plant 150 (through the second
incoming conduit 132). Alternatively, in other embodiments, the
cistern 120 and the pump station 130 may be configured such that
there is a sufficient elevation drop between them to allow
hydrostatic pressure to cause the flow of stored rainwater from the
cistern 120 to the wet well of the pump station 130. Indeed, the
wastewater treatment plant 150 and the pump station 130 may be
likewise configured such that the reclaimed water flows to the wet
well of the pump station 130 due to hydrostatic pressure, rather
than any pumping mechanism.
[0038] According to some embodiments, the pump station 130 is
configured to prefer holding rainwater from the cistern 120 rather
than reclaimed water from the wastewater treatment plant 150. In
such embodiments, the pump station control panel 135 may be
configured to either operate the pumps 133 to pump rainwater from
the cistern 120 or allow the rainwater to flow in through the first
incoming conduit 131 due to gravity, whenever the level measuring
devices 134 indicate that the level of water within the pump
station 130 has reached a predetermined minimum amount. Indeed, the
pump station control panel 135 may be configured to operate the
pumps 133 or otherwise allow the flow of rainwater through the
first incoming conduit 131 until the level measuring devices 134
indicate that the level of water within the pump station 130 has
reached a predetermined desired amount, at which point the pumping
will cease. It should be understood that all processes of the pump
station 130 may be controlled by one or more computer programs of
the pump station control panel 135, as is appreciated by those
skilled in the art. In such embodiments, the pump station 130 may
be configured to only allow the rainwater from the cistern 120 to
flow into the wet well of the pump station 130 until the water
level in the wet well reaches a predetermined maximum amount.
[0039] In some embodiments, the pump station control panel 135 is
further configured to allow reclaimed water to enter the pump
station 130 only when the pump station 130 is unsuccessful in
replenishing its storage of water to the desired level with
rainwater alone, either by operating the pumps 133 or by opening
the interface of the wet well and the first incoming conduit 131 to
allow the reclaimed water to flow in due to gravity. Therefore,
according to some embodiments, the pump station 130 will
preferentially hold rainwater from the cistern 120, but may hold
reclaimed water in the event the cistern 120 is low or dry, for
example, during periods of little to no rainfall.
[0040] As described above, according to some embodiments, the pump
station 130 is configured to maintain water (either rainwater,
reclaimed water, or a combination of the two) inside the wet well
of the pump station 130 within a specific level range or,
alternatively, at a specific level until a demand for the water is
made. In embodiments where the water is to be maintained at a
specific level, the predetermined minimum level and the
predetermined desired level are the same. It is necessary that the
pump station 130 maintain water at or above a particular level so
that there is enough water in the pump station 130 to be
transferred to the rainwater treatment system 200 on the demand of
users within the building. According to a preferred embodiment, the
pump station 130 has a first outgoing conduit 136 that connects the
pump station 130 to the rainwater treatment system 200 and carries
water from the wet well of the pump station 130 to the rainwater
treatment system 200 on demand from the point-of-use.
[0041] In some embodiments, the pump station also has a second
outgoing conduit 137 that carries water (directly or through a
series of conduits) from the pump station 130 to a particular
point-of-use, without passing through any treatment system or
undergoing any treatment process in between. Therefore, unlike
secondary uses within a building, there may be some uses that do
not require treatment of the water at all prior to use. For
example, irrigation and agricultural uses do not require treated
water. So while the primary uses require potable water and the
secondary uses require non-potable water, but with some treatment
to prevent compromising the building's plumbing, the agricultural
and irrigation uses require no treatment whatsoever, and the water
may be pumped directly to the point of use from the pump station
130. Therefore, in the event a demand is made for water at a point
of use corresponding to agricultural or irrigation use, the water
may be transferred from the pump station 130 to the point-of-use
through the second outgoing conduit 137.
[0042] With reference now to FIG. 2, a rainwater treatment system
200 according to a preferred embodiment of the invention is
provided. The rainwater treatment system 200 may be located within
the building in which the treated water is to be used, or it may be
located in a remote location. In some embodiments, one rainwater
treatment system 200 supplies treated water for numerous buildings.
The rainwater treatment system 200 includes a pressurizing device
210, a pH adjustment system 220, a filtration system 230, an
ultraviolet disinfection system 240, and a chemical disinfection
system 250. Each of the foregoing components of the rainwater
treatment system 200 is connected via conduits to at least one
other component such that water may flow from one component to
another through the conduits. The direction of flow between
components in accordance with some embodiments is indicated by the
arrows in FIG. 2. Therefore, as illustrated in FIG. 2, in some
embodiments, water may flow through the conduits from the
pressurizing device 210 to the pH adjustment system 220 to the
filtration system 230 to the ultraviolet disinfection system 240 to
the chemical disinfection system 250. It should be understood,
however, that the configuration of the components illustrated in
FIG. 2 is not exclusive; indeed, there are numerous other potential
configurations that may be recognized by those skilled in the art
that are within the scope of the present invention. Thus, in other
embodiments, and as discussed in greater detail below, water may
not flow between components in the manner illustrated in FIG.
2.
[0043] In some embodiments, the pressurizing device 210 is
configured to receive water originating in the pump station 130
through an incoming conduit. The pressuring device 210, according
to some embodiments, is further configured to pressurize the
incoming water such that it may pass through the remaining
components of the rainwater treatment system 200 and be usable at
the point-of-use within the building. Therefore, the degree of
pressurization is dependent upon the particular environment and
configuration of the rainwater treatment system 200 as well as the
particular components utilized in the rainwater treatment system
200. In some embodiments, the pressurizing device 210 is one or
more hydro-pneumatic tanks. In addition to the incoming conduit,
the pressurizing device 210 also has an outgoing conduit that is
configured to carry the pressurized water to another component in
the rainwater treatment system 200, which is, in some embodiments,
the pH adjustment system 220.
[0044] Rainwater is generally acidic in nature. In some
embodiments, the pH adjustment system 220 is configured to
neutralize the acidity of the rainwater by raising the pH level.
This advantageously reduces the potential corrosive damage that
could be caused to the metal conduits and devices employed within
the rainwater treatment system 200, as well as the general plumbing
of the building, due to contact with the acidic rainwater. For that
reason, in some embodiments, and as illustrated in FIG. 2, the
rainwater treatment system 200 is configured such that water is
directed to the pH adjustment system 220 prior to any of the
filtration or disinfection components. Alternatively, the pH
adjustment system 220 may be positioned within the rainwater
treatment system 220 such that the water must pass through various
other filtration and/or disinfection components prior to reaching
the pH adjustment system 220, but such a configuration would not be
as advantageous, as it would reduce the anti-corrosion benefits
provided by the pH adjustment system 220 to the other system
components.
[0045] Any type of pH adjustment system 220 now known or hereafter
developed may be utilized in accordance with embodiments of the
present invention. In some embodiments, the pH adjustment system
220 is simply one or more calcite filters that allow the water
arriving from the pressurizing device 210 to pass through calcite
media. Calcite filters may be a good choice for the pH adjustment
system 220 because they are inexpensive and easy to maintain. In
some embodiments, the pH adjustment system 220 is configured to
direct the water, once its pH has been neutralized, through a
conduit to another component of the rainwater treatment system,
which is, according to some embodiments, the filtration system
230.
[0046] According to some embodiments, the filtration system 230 is
configured to remove particulate matter and suspended solids from
the water. Any number of devices may be utilized in the filtration
system 230, including filtration systems now known or hereafter
developed. According to different embodiments, the filtration
system 230 may include disc filters, cartridge filters, membranes,
or other filter media designed to remove solids from the water.
Indeed the filtration system 230 may include a combination of
different types of filter media or a series of filter media of the
same type, but designed to filter out solids of different sizes. In
some embodiments, the filtration system 230 is configured to remove
particulate matter at or above 5 microns in size. In addition to
the filter media, the filtration system 230 may also include,
according to some embodiments, a backwash system to remove the
captured particulate matter from the filtration system 230 and a
cleaning device to maintain the filter media free from blockages
and build-up. In some embodiments, pressure indicators 232 are
provided on the incoming and outgoing ends of the filtration system
230 to measure the pressure drop across the filter(s). These
pressure indicators 232 transmit the pressure differential
measurements to a master system control panel 280, which may
utilize the measurements to determine when replacement filter media
is required.
[0047] According to some embodiments, the rainwater treatment
system 200 is configured such that the water, upon passing through
the filtration system 230, is directed to an ultraviolet (UV)
disinfection system 240. In some embodiments, the UV disinfection
system 200 includes a UV lamp(s) that irradiates bacteria and
microorganisms present in the water passing through the UV chamber.
While it is possible that rainwater treatment system 200 may be
configured such that the UV disinfection system 240 is positioned
such that the water reaches the UV disinfection system 240 prior to
passing through the filtration system 230, it is preferable that
the rainwater treatment system 200 is configured such that the
water arriving at the UV disinfection system 240 for irradiation
has already been filtered by the filtration system 230, as the
presence of particulate matter in the water, particularly large
suspended solids, can negatively impact the effectiveness of the UV
irradiation process. Indeed, bacteria and microorganisms may be
buried within such solids so that they are shielded from the UV
light and may pass through the unit without being destroyed.
Therefore, to maximize the efficacy of the UV disinfection system
240, according to some embodiments, the UV disinfection system 240
is configured to receive water transferred to it through conduits
from the filtration system 230.
[0048] In some embodiments, a chemical disinfection system 250 is
provided within the rainwater treatment system 200 such that the
chemical disinfection system 250 is configured to receive through
conduits the water that has just passed through the UV disinfection
system 240. Therefore, according to some embodiments, the
disinfection of the water being treated by the rainwater treatment
system 200 is a two-stage process. The chemical disinfection system
250 may simply inject a chemical disinfecting solution such as
chlorine into the water that is traveling through the conduits to
the point-of-use, or the chemical disinfection system 250 may
redirect the water into a chemical disinfection unit of some type.
In some embodiments, the chemical disinfection system 250 is an
onsite sodium hypochlorite generation system that both generates a
chlorine solution and introduces the chlorine solution to the water
to be treated. In other embodiments, the chemical disinfection
system 250 is another type of chlorine disinfection system, such as
tablet chlorinator. The onsite hypochlorite generation system may
include, for example, a brine tank, a generator, a chemical storage
tank, and a metering pump and the chlorine solution generated may
be a 0.8% sodium hypochlorite solution. Regardless of the
particular instruments utilized by or incorporated into the
chemical disinfection system 250, the chemical disinfection system
250 is configured to introduce a disinfecting chemical solution
into the water to provide additional disinfection (beyond that
provided by the UV disinfection system 240) and a residual
concentration of disinfectant that will advantageously prevent
regrowth of bacteria and microorganisms in the water
downstream.
[0049] There are various locations within the rainwater treatment
system 200 that the chemical disinfection system 250 may be
positioned without affecting the efficacy of the chemical
disinfection system 250. Therefore, according to different
embodiments, the chemical disinfection system 250 may be configured
to introduce the disinfecting solution to water traveling through
the rainwater treatment system 200 either before or after the water
passes through the pH adjustment system 220, the filtration system
230, or the UV disinfection system 240, again to prevent biogrowth
on these components of the treatment system. Indeed, in some
embodiments, the chemical disinfection system 250 may be configured
to introduce the disinfecting solution at more than one point in
the rainwater treatment system 200. According to other embodiments,
the chemical disinfection system 250 may be positioned and
implemented within the rainwater treatment system 200 such that it
treats only a predetermined portion or amount of water that is
passing through the conduits of the rainwater treatment system 200.
In some embodiments, rainwater treatment system 200 is configured
such that after the water has been treated by the pH adjustment
system 220, the filtration system 230, and the UV disinfection
system 240, a particular amount or portion of the water is
redirected to the chemical disinfection system 250, also known as a
"recirculation loop." According to such embodiments, the rainwater
treatment system 200 may be configured such that the portion of
water treated by the chemical disinfection system 250 is, after
treatment, directed to rejoin the water in the conduits on the way
to point-of-use.
[0050] Alternatively, according to other embodiments and as
illustrated in FIG. 2, the rainwater treatment system 200 may be
configured such that the water treated by the chemical disinfection
system 250 is, after treatment, directed to join the water that has
not yet been fed to any of the pH adjustment system 220, the
filtration system 230, or the UV disinfection system 240. This
creates a loop that allows continuous circulation of water through
the pH adjustment system 220, the filtration system 230, and the UV
disinfection system 240, even when there is no demand for water at
the point-of-use. This is advantageous as certain systems within
the rainwater treatment system 200, such as the UV disinfection
system 240, may require a minimum flow rate. It is also
advantageous because the chlorine present in the water may help
prevent biogrowth on the devices utilized in the pH adjustment
system 220, the filtration system 230, and the UV disinfection
system 240.
[0051] In connection with the chemical disinfection system 250,
according to some embodiments, several chlorine sensors are
provided within the rainwater treatment system 200 to measure the
residual chlorine level in the water passing through the system. In
some embodiments, the chlorine sensors communicate the chlorine
level measurements to the master system control panel 280, which is
configured to direct the chemical disinfection system 250 to add
more or less chlorine solution depending on the measurements in
order to maintain a residual chorine level sufficient to prevent
regrowth of bacteria. For example, in the event water is
continuously circulating in the rainwater treatment system 200 due
to no demand at the point-of-use, the chlorine sensors may indicate
that sufficient levels of chlorine are present in the water due to
previous introduction. According to some embodiments, this
indication from the chlorine sensors would be recognized by the
master system control panel 280, which would cause the chemical
disinfection system 250 to cease introduction of additional
chlorine into the water as the water passes through the chemical
disinfection system 250. In this way, the amount of chlorine
present in the water at the point-of-use is maintained at a
relatively constant level, even if the water is recirculating in
the system.
[0052] In addition to the components described in detail above,
various other measurement tools may be provided in the rainwater
treatment system 200 that interface with the master system control
panel 280, which utilizes the signals from the tools to manage the
processes of the components of the rainwater treatment system 200
discussed above. As previously discussed, pressure indicators 232
are provided on either end of the filtration system 230 and
chlorine sensors are provided prior to introduction of the water to
the chemical disinfection system 250. In addition to these tools,
additional pressure indicators, chlorine sensors, flow meters, pH
sensors, and other measurement tools may be provided to monitor the
processes taking place within the rainwater treatment system 200.
The master system control panel 280 is configured to receive
transmissions from each of these tools, process the transmissions
based on predefined rules, and take specific action (or instruct
particular components of the rainwater treatment system 200 to take
specific action) based on specific transmissions. For the purposes
of example only, in the event a flowmeter indicates reduced flow,
the master system control panel 280 may initiate an increase of the
pressurization caused by the pressurizing device 110.
Advantageously, the master system control panel 280 allows the
rainwater treatment system 200 to be somewhat automated and to be
managed and controlled when necessary by individuals through use of
a computer.
[0053] As the systems of embodiments of the present invention have
been described above, exemplary embodiments of methods of
recovering and treating rainwater shall now be described with
reference to FIGS. 4 and 5. FIG. 4 is a flow chart that illustrates
method of recovering and managing rainwater in anticipation of
secondary use in buildings, according to some embodiments of the
invention and FIG. 5 is a flow chart that illustrates a method of
treating rainwater for secondary use in buildings, according to
some embodiments of the invention.
[0054] As represented by block 402 of FIG. 4, falling rain is
captured by a rainwater capturing device 110 on the roof of a
building and conveyed via the storage conduits 112 to the cistern
120 for storage. From the cistern, as shown in block 404, the
stored rainwater may be pumped into the pump station 130 through
the first incoming conduit 131 of the pump station 130 in
anticipation of use. In some embodiments, the operations of the
pump station 130 are controlled by the pump station control panel
135. In certain embodiments, the pump station control panel 135
operates the pumps 133 within the pump station 130 in order to
maintain the level of water stored in the pump station 130 at a
particular level, as measured by the level measuring devices
134.
[0055] As represented by block 406, the pump station control panel
135 determines whether the rainwater pumped into the pump station
130 from the cistern 120 is sufficient to cause the level of water
in the pump station 130 to meet the desired level. If it is not, as
shown in block 408, the pump station control panel 135 operates the
pumps 133 to pump reclaimed water originating in a wastewater
treatment plant 150 into the pump station 135 to make up the
deficit. In this way, there is always a certain amount of water
(whether rainwater, reclaimed water, or a combination) in the pump
station 130 to be transferred to the rainwater treatment system 200
on demand from a point-of-use in the building or elsewhere.
Therefore, according to some embodiments, and as represented by
block 410, in the event there is a demand for secondary use within
the building, water is pumped from the pump station 130 to the
rainwater treatment system 200 to be treated by the rainwater
treatment system 200 prior to reaching the point of use.
Alternatively, and also in accordance with block 410, in the event
there is a demand for irrigation use, the water from the pump
station 130 is pumped directly to the point of use.
[0056] Now referring to FIG. 5, when the water from the pump
station 130 is pumped to the rainwater treatment system 200 for
indoor secondary uses, it undergoes a method of treatment, an
example of which is illustrated in FIG. 5. First, as represented by
block 502, the water is pressurized by the pressurizing device 210
to ensure that the water may flow through the conduits and each
component of the rainwater treatment system 200 and arrive at the
point of use with enough pressure to be usable. Next, as
represented by block 504, the water is neutralized by the pH
adjustment system 220. In some embodiments, the water passes
through calcite filters that reduce the acidity of the water. After
the pH has been neutralized, and as represented by block 506, the
water is filtered by a filtration system 230 to remove particulate
matter and suspended solids at or above a certain size in diameter.
From there, according to some embodiments and as shown in block
508, the water then flows through a UV disinfection system 240 that
utilizes light from an ultraviolet lamp to irradiate bacteria and
microorganisms.
[0057] In some embodiments, following UV disinfection, a chlorine
sensor is utilized to measure the residual level of chlorine in the
water and the master system control panel 280 compares the
measurement to a specified desired amount of residual chlorine. As
represented by block 510, the master system control panel 280 makes
a determination as to whether the residual level of chlorine in the
water is adequate. If it is determined that the chlorine level is
not adequate, a chlorine solution is introduced into the water by a
chemical disinfection system 240 such as an onsite sodium
hypochlorite generation system or other chlorination systems, and
as represented by block 512. In the event it is determined that the
chlorine level is adequate, perhaps due to recirculation of water
through the rainwater treatment system 200, no additional chlorine
will be added. Once all of the foregoing actions have been taken,
according to some embodiments and as shown in block 514, the water
leaves the rainwater treatment system 200 and travels through the
plumbing of the building to the point of secondary use.
[0058] While certain exemplary embodiments have been described and
shown in the accompanying drawings, it is to be understood that
such embodiments are merely illustrative of and not restrictive on
the broad invention, and that this invention not be limited to the
specific constructions and arrangements shown and described, since
various other changes, combinations, omissions, modifications and
substitutions, in addition to those set forth in the above
paragraphs, are possible. Those skilled in the art will appreciate
that various adaptations and modifications of the just described
embodiments can be configured without departing from the scope and
spirit of the invention. Therefore, it is to be understood that,
within the scope of the appended claims, the invention may be
practiced other than as specifically described herein.
* * * * *