Graywater recycling system including rainwater recovery
A graywater recycling system having separate graywater and blackwater drain lines and a graywater flushing line connected to an upstream end of the blackwater drain line. The system is also provided with a subsurface graywater irrigation network with a graywater flushing line connected to the network. A rainwater collection system is in fluid communication with a graywater collection and distribution network. The system may be provided with a fire protection system in fluid communication with the graywater network and the rainwater system. Additionally, the separate graywater and blackwater piping may be run in a trench separator having a divider and closure lids.
This patent application claims priority to co-pending provisional patent application, Ser. No. 60/881,094, filed Jan. 18, 2007.
BACKGROUND OF THE INVENTIONThe present invention relates to an improved graywater recycling system including rainwater recovery. The invention further comprises: a. separate drainage mains from individual residences to an interconnected system for graywater collection, filtration, and recycling; b. a trench separator separating a graywater main and a graywater supply line from a blackwater main; c. an automatic blackwater main flushing and cleaning subsystem providing assurances that effluents are purged from the residential blackwater main to the blackwater piping connected to the sewer treatment plant; and d. a rainwater recycling subsystem providing a water source for fire protection, toilet maintenance, and landscape irrigation. Each of these features are described in further detail below.
The inventor's prior U.S. Pat. No. 6,132,138 discloses a basic graywater recycling system and is incorporated herein by reference for all purposes. The prior disclosure indicates that the underground recycling system may be used for many purposes, including use beyond the single residence setting, such as an entire residential and commercial development using a centralized holding or treatment facility. The prior disclosure does not teach specifically how this may be achieved nor does it disclose the improved features of the present invention.
Spitting the sewer mains to collect graywater for use in a residential subdivision, resort, commercial establishment, communities, villages, towns, cities and military establishments is one aspect of the present invention.
Most single family homes in a subdivision, multi-family units, condos, hotels, motels, businesses, and resort communities currently have only one expensively treated potable water supply line which is plumbed to all the fixtures and may be used to irrigate the landscape. There is only one sewer main. This sewer main is installed in the unit's foundation and collects 100% of the used potable water, wastewater or effluent from all of the fixtures in the unit. Blackwater and graywater collected in this one sewer main is directed into the street sewer and eventually ends up in the city sewer plant for treatment. This sewer main contains the blackwater which is effluent from the toilets, the kitchen sink and the dishwasher. These fixtures account for only approximately 35% of the total wastewater in a home. The other 65% of the wastewater is called graywater. Graywater is effluent from the lavatories, bathtubs, showers, washing machine and any air conditioning condensate lines.
The present invention will split or separate the effluent in order to capture the graywater with all its nutrients for use in an underground irrigation system called “GrayScaping” for use in an entire subdivision to include condos, town homes, hotels or resorts. From the home, the graywater is directed to the street via piping in a joint trench shared with the blackwater main as discussed further below and illustrated in
An advantage of the present invention is that it reduces the size of the existing blackwater sewer mains in a home from a standard 4″ line down to a 3″ blackwater sewer main since it is collecting only 35% of the wastewater rather than 100%. This then allows the builder to reduce his cost and apply it to the cost of installing the separate graywater main. Further piping size reductions are gained in the blackwater main from a typical 8″ main down to a 6″ main on side streets and from a 12″ main down to an 8″ main on the primary street line to the city sewer.
Another feature of the present invention of splitting the mains solves a problem of not having sufficient blackwater to flush the solids from the structure to the street main. This problem is solved as illustrated in
A second pressurized “flushing or cleaning” system is provided for each of the underground irrigation's sections used.
The present invention also directs a pressurized rainwater supply line (73) from a rainwater system to “RainScaping Toilets” to help flush effluent in the blackwater mains to the street by allowing 5 gallons of rainwater per flush to flush these toilets (see
There are numerous benefits of the present inventive system. The developer will be paying for only the trenching, graywater piping and the facilities that are required at the central recycling plant. The builder will be paying for splitting the mains and installing the GrayScaping irrigation system in each home required for the overall system.
By downsizing the blackwater mains, the developer can offset this cost and apply it to the cost of installing the graywater mains. The developer also gains more building lots per acre since city and state regulations restrict a certain number of homes per acre depending upon the amount of wastewater per day the utility has to treat. This adds up to a tremendous amount of savings to the developer which will more than offset the entire graywater and rainwater recycling system costs for the entire subdivision.
Theoretically, by reducing the amount of wastewater to only 35% of that traditionally used, a developer may add two more $50,000-lots per acre. If he is also the builder, he may build two (2) additional $200,000-homes per acre. If he makes a $50,000 per home profit, in a 500-acre development, a developer/builder could make up to a hundred million dollars in profits by using the present inventive system.
A problem facing developers of new projects has been concerns over wastewater treatment and disposal of the treated wastewater. Area residents, community leaders, state and federal authorities are concerned that excessive wastewater will end up in creeks, streams, rivers or lakes and eventually end up in underground aquifers . . . the main supply of drinking water. A 3,500 home development will produce over 1,400,000 gallons per day or over 511,000,000 gallons annually of wastewater which includes the graywater.
The present invention of “splitting the mains” in every structure in the development allows for capture of the graywater produced from these units and the recycling of the graywater with all its nutrients. Any graywater not recycled may be directed to the standard treatment plant.
A portion of the treated effluent from a sewer treatment plant (74) may be directed to a rainwater tank (102) in the graywater/rainwater/fire protection recycling plant of the present invention as shown in
The present inventive system may be used for an entire development including irrigating a community greenbelt landscape or associated golf course. It may be used in commercial establishments associated with the development. A developer may extend the system into the city, county or state street, road or highway along the front of his development. All graywater and all reclaimed water from the treatment plant may be separately metered and computer monitored. This will provide data for the developer for designs of future developments.
In a rural subdivision where there is not a city public water system, a developer must drill sufficient water wells and pay engineering costs to design a water system plant large enough to handle a 3,500 home development. The developer must ensure water mains are large enough to supply the entire community. There is often concern that the development, with its deep commercial wells, will deplete aquifer supplies of drinking water. Again, the present invention of splitting the mains and installing the GrayScaping irrigation system in each home as part of the inventive system eliminates the expensive process of watering the landscape with potable water. Landscape watering is often the largest water use in a home. Instead of having to treat the graywater effluent, the present invention simply collects it from the homes, filters it, pressurizes it and returns it to each of the homes from where it was collected for irrigation of the landscaping.
Each GrayScaped yard will allow a homeowner to save up to 100,000 gallons of potable water annually by using graywater for irrigation. The developer saves by downsizing his water plant and his water mains and not having to drill as many wells. The developer/builder may advise the concerned individuals that the aquifer is not being depleted. The developer/builder in fact may be saving up to 490,000,000 gallons of water annually by splitting the mains to collect their graywater and using it on landscaping instead of using well water. Another savings the developer may advise concerned individuals is that a rainwater recycling system (“RainScape”) may be used to flush every toilet in every home in the subdivision (see
Additional benefits of the present invention to the developer include:
a. the developer may qualify to acquire federal grants for installing graywater systems that are available from many federal organizations;
b. the developer may acquire low interest loans for installing graywater systems that are available from many federal organizations;
c. the developer may acquire tax incentives for installing graywater systems;
d. the developer will be able to acquire tax incentives for installing rainwater systems that are available from the counties, towns or cities; and
e. the developer may acquire money for installing fire protection systems from the insurance companies.
Benefits to a builder include:
a. by splitting the mains and by downsizing the blackwater main, the builder may apply the cost saving to the cost of installing the graywater main;
b. the builder may effectively have more lots to build on in the development by splitting the mains due to the rule of the developer getting more homes per acre due to less sewage treatment;
c. the builder may reduce the likelihood of foundation and home cracking by controlling the moisture content around the slab in expansive soils. This may prevent costly lawsuits, bad reputations, unhappy homeowners and the cost of having to repair the damage. Avoiding these adverse costs may result in savings which more than offset the cost of splitting the main and installing the GrayScaping system. The additional cost to install the present inventive system is not much more than the cost of most aboveground sprinkler systems which the builder typically installs.
Benefits of the present inventive system to the utility provider include:
a. not having to treat up to 350,000,000 gallons of water annually (due to the developer splitting the mains to collect their graywater and to use it in their landscaping instead of the potable water);
b. not having to treat up to 140,000,000 gallons of potable water annually (due to the developer splitting the mains to collect graywater and to use it to flush toilets instead of by using potable water); and
c. not having to treat up to 350,000,000 gallons of sewage (graywater) annually (due to the developer splitting the mains to collect graywater and to use it in landscaping instead of potable water).
Benefits to the homeowner include:
a. the home owner saves up to 140,000 gallons of potable water annually that they would have had to pay for if the mains were not split and potable water was used to irrigate landscaping and to flush toilets;
b. the home owner saves in repairs for expensive foundation and home cracks with the use of graywater around the foundation in expansive soils;
c. the home owner saves in repairs to the home due to damaging termites and wood cutting ants with automatic injections of pesticides into the graywater;
d. the homeowner saves by eliminating the pest control costs for treating for fire ants, scorpions, grub worms and any other damaging insects in the yard with automatic injections of insecticides into the graywater;
e. the homeowner saves in having to fertilize the yard and puts an end to above ground applications with automatic injections of fertilizers into the graywater; and
f. the homeowner saves by not having to replace the landscaping every time a drought hits and the utility's rationing program is enforced.
Benefits to concerned individuals (including city and state officials) include:
a. they are satisfied to know the developer will not be dumping raw sewerage into creeks, streams, rivers or lakes and potentially polluting underground aquifers; and
b. they are satisfied to know the developer will not be depleting underground aquifers of drinking water
Turning to
This trench is called “TrenchScaping”.
The trench separator (80) is installed first in the trench and then the blackwater and graywater mains are installed in the connected trough section. A sensor wire (not shown) is then attached to the mains to detect any breaks and notify the provider of break along with the location. A rubberized lid (84) will be inserted on top of the trench separator for additional protection. This will eliminate having to install the expensive, required “bedding sand” and will also act as a sleeve when crossing a potable water line which is required by many local and state rules and regulations. In case of a break in the blackwater main, the leaking effluent will simply run down the trough to the end of the line and will flow back into the sewer main through a trough diverter fitting. There will be no dirt going into the sewer because of the lid. This lid may also prevent breakage from backhoes since the trench separator will be a durable rubberized or plastic product and may be provided with bright color coding to indicate either graywater and blackwater. If either of the graywater mains breaks, the leaking effluent will simply run down the trough and flow into the graywater holding tanks through the trough diverter fitting.
A line is installed from the graywater pressure supply line to the homes and is properly tied into the blackwater main on an angle (see
Yet another portion of the present invention is illustrated in
a. Injection tank (1) (
b. Filters (56) (
c. Booster pumps (3) (
d. Booster pumps (4) for rainwater system (two each);
e. Standby water source (106) (well or public water supply) (
f. Transducer (6) (
g. Pressure relief safety valve (7) (
h. Suction pump (8) (
i. Suction pump (9) (
j. Automatic controls (10) (
k. Adjustable time clock (11) (
l. Adjustable float switch (12) (
m. Adjustable float switch (13) (
Any overflow may be diverted to a small lake or pond (100) where it may be used to resupply the rainwater tank (102) when needed. Any excess from the lake will overflow into a detention pond and/or overflow into the retention pond as needed. The detention pond will maintain the small lake's level. As an alternative, if there is still too much overflow, the level of the lake may be maintained with above ground sprinkler heads to irrigate parks and greenbelts. Alternatively, it may be distributed around the subdivision for fire protection.
As may be seen in
A submergible pump is installed in the retention pond which is controlled by a float system to activate the pump when the retention pond becomes full. When it gets low, the controller shuts off the pump. A line is run from the pump to a series of smaller reserve rainwater tanks (104) (
When no city sewer or any retention ponds are required, the water supply for the rain water collection tank may be the treated effluent from a sewer treatment plant (106). A line (74) will be run to the top of the tank (102) and automatically be discharged into the rainwater tank. When full, it will overflow to the detention pond or small lake with waterfalls for aeration of the system. This aerates the rainwater tank in the filling process. The 98% treated effluent may have elevated chlorine levels, but will be diluted by the larger volume of collected rainwater and should be safe for the environment. An introduced chlorine may disinfect the rainwater of bacteria entering the system from the roof or gutter of a house. A meter, a cut-off valve and an air gap may be installed in this automatic fill line prior to entering the rainwater tank.
Further yet another aspect of the present invention shown in
A secondary supplementary water supply for the rainwater collection system may be the potable water introduced into line (74) which extends to the top of the collection tank (102) where it will have an air gap when filling. Again, this aerates the rainwater tank during the filling process. When there is insufficient treated effluent from the sewer treatment plant (106) and not enough rainwater to keep the rainwater tank full, the potable water supply will activate through a solenoid valve in line (74). This insures that the rainwater tank will have a sufficient water supply for flushing toilets, supplementing the graywater tank, and available for use in the event of a fire. When the water level reaches a cut off probe at a pre-determined fill level below the overflow, a signal is sent to the solenoid valve to shut off the potable water supply.
A pipe (114) (
One function the rainwater tank (102) serves is to be the primary supplemental water supply (17) for the graywater collection tanks (
A second function the rainwater collection tank (102) serves in the present invention relates to “RainScaping Toilets” discussed above. A pressurized rainwater supply line (73) (
A further function the rainwater collection tank (102) plays is to provide pressurized rainwater via pressurized rainwater tank 951) and feedline (99) (see
Station #1 may have one sprinkler head placed at the front of the house at the very top of the ridge, one sprinkler head at the other end of the ridge, and one sprinkler head in the middle of the ridge for double coverage which may wet the roof and keep hot ashes or sparks from starting a fire on the roof. These heads may be full circle so they may also be wetting down the yard. The system may be installed with 20 gallon per minute heads or to any National Firefighters Protection Association's requirements.
Station 2 may have one sprinkler head placed at each corner of the roof and adjusted to cover the yard.
Station 3 may have one sprinkler head placed at each corner of the house in the yard and adjusted to cover the yard. This will provide double coverage for the house.
Station 4 may have one sprinkler head placed at each corner of the lot and at the top of the fence and may be adjustable to cover wetting down the house. Since they may be full circle heads, they could also wet down the neighboring house or help contain a fire until the firefighters arrive.
The fire protection system may be a dry system to prevent freezing. A 1″ PVC drain line may be tied into the line 6″ above each of the systems control valves. Another control valve may be installed in the drain line to allow the drain line to close when the FireScaping system is activated and may open when the system shuts off. This would allow water to drain out of the system and drain to any of lavatories as is well-known with air conditioning (A/C) condensate lines.
A non-toxic fire protection liquid can be injected into the system at the central plant to help with putting the fire out.
The “FireScaping” system may be monitored and controlled through a laptop or desktop computer by the local fire department, the utility provider, or the property owner's association.
An inside sprinkler system may be installed. The FireScaping system allows activated heads to be automatically shut off in a predetermined time to avoid water damage to the home and only the heads in the room with the fire activated.
A manual override button may be placed in each room where there are heads. The water may be shut off with the button only if the head is activated.
The heads may be turned on again if the fire starts up again. Once the fire has been controlled, the button may be reset.
Turning again to the underground irrigation aspects of the present invention (see
The collected graywater is then filtered, but not treated, to retain the nutrients for landscaping. It is then pressurized and routed back to each residence or establishment via a graywater supply line (71) for use in a foundation watering system (EGW) (
The improved system of the present invention provides an automatic, underground, pressurized irrigation system installed 4″ to 5″ underground, near the root system of the landscape. The system may requires the builder or landscaper to install a minimum of 6″ of sandy loam topsoil to allow the graywater to easily flow throughout the topsoil. Soil activators injected into the graywater at the central plant on a monthly or quarterly basis may ensure that the soil maintains its structure.
The underground GrayScaping irrigation system is tied into the regulated, pressurized supply line stubbed out at the front or back of the lot (see
With this system, the irrigation system may be custom designed for each home and eliminate any “stripping” or areas not getting adequate water. Each grid of pipes includes an automatic air valve at the high side of the grid which allows air to escape the grid when the control valve is opened initially for watering and an automatic drain valve at the low side of the grid to allow the draining of the grid when the control valve shuts off the grid. This prevents the grid from freezing.
The present inventive system may incorporate a designated portion of the graywater pressurized supply line (200) (
Turning again to
Graywater (and any supplemental treated water) enters a first collection tank (52) sized according to one-half of the development's usage of treated water and the graywater. This represents 100% of the water that entered the house and that 100% is recycled and used in the landscaping for homes and the subdivision. The tank (52) is built to have a separator (110) (
If the graywater level drops, a solenoid valve located at the bottom of the rainwater tank opens and feeds rainwater to fill the graywater tank (52). This helps aerate the graywater tank. At the appropriate level, the solenoid valve shuts off the rainwater to this tank. Graywater overflow flows to a second graywater tank (52a). If the rainwater system gets low, a control system (including transducers, probes, and/or floats) installed in the rainwater tank turns on a solenoid valve on a 2″ line from the pond or lake, and recharges (from the top) the rainwater tank. When a float reaches a rainwater level just below the overflow that goes to fill the pond, a signal is transmitted to shut off the solenoid valve on the pipe from the pond. The pond has waterfalls and fountains for aeration and has the same float system and an overflow to go to a detention pond to maintain the level of the pond. Any overflow in the detention pond will flow into the retention pond where a pump is installed to take this water to a series of tanks for reserves to be used as a supplementary water supply to the rainwater tank at the plant. The rainwater tank also uses the same process for overflow. The rainwater uses potable water to supplement a depleted tank. A pre-determined low level may supply the potable water automatically. A meter and a cut-off valve are installed in the potable water line and will have an air gap when filling at the top of the rainwater tank. When the float reaches a level just below the rainwater tank's overflow, a signal is sent to the solenoid valve to shut off the potable water line which ensures that there will be a supply of graywater for irrigation, sufficient rainwater to flush all the toilets in the subdivision, and sufficient rainwater in the fire protection system. A meter, cut-off valve and backwater valve (or double check valve) may be installed in this automatic rainwater tank fill line prior to the graywater tank.
A 1¼″ line from a small pump may be extended to the graywater and rainwater tank's automatic sediment cleaning system including a piping system installed at the bottom of the tanks with suction heads to keep sediment from settling and caking up. This small pump is automatically turned on periodically to draw any settled sediment from the bottom of the rainwater and graywater tanks and pump it into a small aerobic system to be filtered and recycled into the graywater tanks. This also allows aeration of the graywater tanks. A line extends from pump #1 in the pump house (55) to inside graywater tank (52) with a pump screen covering the end of the pipe. This is used for pumping the graywater into the graywater pressure tank (58) which is regulated by a compressor in the pump house. It also has a probe system which will turn pump #1 on when the graywater level reaches the pre-determined lower level. When it reaches the pre-determined upper level the probe sends a signal to a control box to shut off pump #1.
A second graywater tank (52a) may serve as a back-up and an alternate system for the first tank (52). It is designed like the first graywater tank except pump #2 in the pump house will not come on unless the float rises to a level of graywater below the overflow and signals it to come on. As soon as pump #2 comes on, pump #1 is shut down. As long as graywater is being overflowed from tank #1 (52) into tank #2 (52a) and does not reach a lower probe, pump #2 will continue pumping from this tank (52a). As soon as the graywater level reaches the lower probe, pump #2 will be shut off and pump #1 will resume the pumping from tank #1 (52). An automatic sediment cleaning system (110) also may be installed inside tank #2 (52a) and use the same pump as tank #1 (52). The overflow (54) (
Claims
1. A graywater recycling system comprising:
- separate graywater and blackwater drain lines; and
- a graywater flushing line connected to an upstream end of said blackwater drain line.
2. A graywater recycling system comprising:
- a subsurface graywater irrigation network; and
- a graywater flushing line connected to said network.
3. The graywater recycling system of claim 1 further comprising:
- a rainwater collection system in fluid communication with a graywater collection and distribution network.
4. The graywater recycling system of claim 1 further comprising:
- a graywater collection and distribution network; and
- a flushing water source provided by said graywater network.
5. The recycling system of claim 4 wherein said flushing water source is further in fluid communication with a rainwater collection and distribution network.
6. The graywater recycling system of claim 3 further comprising a fire protection sprinkler system in fluid communication with the graywater collection and distribution network.
7. The recycling system of claim 3 further comprising a sediment cleaning system.
8. The recycling system of claim 1 further comprising a pipe trench having a divider separating graywater and blackwater piping.
Type: Application
Filed: Jan 18, 2008
Publication Date: Jul 24, 2008
Inventor: Larry Wayne Haese (San Antonio, TX)
Application Number: 12/009,560
International Classification: E03B 1/04 (20060101);