SOAK PIT SYSTEM FOR THE TREATMENT AND INFILTRATION OF HOUSEHOLD GREYWATER

Abstract

ABSTRACT The present invention relates to a soak pit system for the treatment and infiltration of household greywater comprises of an a cuboidal collection tank (110) that collects greywater from household sources (115), ensuring a hydraulic retention time of at least thirty minutes for settling suspended solids, the tank (110) includes a T-shaped dip pipe (120) with a coarse filter (125) for removing oil, grease, and grit, filtered greywater flows into a primary treatment chamber, a plastic barrel (210) equipped with an inlet discharge pipe (130) and four T-shaped dip pipes (120), this chamber settles scum, sludge, and organic matter, the second cylindrical chamber, made of precast concrete, provides secondary treatment with a two-day retention time and layered filtration, finally, greywater moves to the dispersion and infiltration chamber for soil infiltration, completing the treatment process with periodic maintenance.

Specification

Description:FIELD OF THE INVENTION

[0001] The present invention relates to a soak pit system for the treatment and infiltration of household greywater that falls under wastewater management, specifically to an innovative soak pit design for the effective treatment and disposal of grey water in rural settings, minimizing land use and costs compared to conventional systems.

BACKGROUND OF THE INVENTION

[0002] A soak pit is crucial for sustainable water management, especially in areas lacking centralized wastewater treatment systems. It plays a vital role in the treatment and disposal of household greywater, which includes water from kitchens, bathrooms, and laundry. By providing an initial and secondary filtration process, soak pits remove contaminants such as oil, grease, and suspended solids, thereby preventing pollution of groundwater resources. The treated greywater is then infiltrated into the soil, promoting groundwater recharge and reducing surface runoff, which can mitigate erosion and flooding risks. Additionally, soak pits are cost-effective and space-efficient, making them ideal for residential and rural settings. Regular maintenance of soak pits ensures their long-term functionality, contributing to environmental sustainability and public health by preventing the contamination of surface and groundwater sources.

[0003] Traditional soak pits, often used in rural and semi-urban areas, are simple structures designed to manage household wastewater by allowing it to percolate into the ground. Typically, these pits are basic excavations filled with gravel, stones, or bricks to facilitate water dispersion. While they are cost-effective and easy to construct, traditional soak pits have significant drawbacks. Their simplistic design lacks advanced filtration, leading to potential groundwater contamination from untreated or partially treated greywater. Over time, traditional soak pits can become clogged with grease, oil, and suspended solids, reducing their efficiency and requiring frequent maintenance. Additionally, they are vulnerable to flooding and rainwater ingress, which can further impair their functionality and lead to environmental health hazards. The absence of a systematic maintenance protocol often results in neglected and malfunctioning soak pits, diminishing their effectiveness in managing wastewater sustainably.

[0004] WO2018225082A1 discloses a a toilet system (100) offering safe and complete waste treatment in a difficult terrain that comprises of a toilet facility (20) inserted into a platform (40), a digester (80) housing a primary vermifilter (60) and a secondary drainage bed (90) that are configured based on ground conditions. The primary vermifilter (60) includes an active zone (52) for digesting effluent, a worm bed (54) with biomedia and a filtration bed (56) with drainage media. The primary vermifilter (60) is housed beneath the toilet facility (20) for hard rock terrain and externally above ground for the terrains of heavy soils and high water tables. The secondary drainage bed (90) can be a planted bed, a soak pit (84) or a soak away system (88). The toilet system (100) greatly reduces risk of contamination, environmental pollution or disease. The toilet system (100) is quick and easy to construct.

[0005] US6428691B1 discloses a compact, environmentally benign onsite waste water treatment and disposal system installed secondary to conventional primary treatment process. It is a method and apparatus for the biological purification and natural disposal of liquid wastes using a secondary single pass trickling filter in conjunction with an evapotranspiration absorption (ETA) tertiary disposal bed.

[0006] Conventionally, many systems had been developed that is capable of performing treatment to grey water, but none of the above mentioned prior arts are capable of collecting greywater from multiple household sources, such as kitchens and bathrooms, settling scum, sludge, and organic matter, thus preventing reducing the load of impurities before secondary treatment and promoting groundwater recharge and reduce surface runoff through effective greywater treatment and soil infiltration.

[0007] In order to overcome the aforementioned drawbacks, there is a requirement to develop a system that is capable of collecting greywater from multiple household sources, such as kitchens and bathrooms, settling scum, sludge, and organic matter, thus reducing the load of impurities before secondary treatment and promoting groundwater recharge and reduce surface runoff through effective greywater treatment and soil infiltration.

OBJECTS OF THE INVENTION

[0008] The principal object of the present invention is to overcome the disadvantages of the prior art.

[0009] An object of the present invention is to develop a system capable of collecting greywater from multiple household sources, such as kitchens and bathrooms.

[0010] Another object of the present invention is to develop a system capable of settling scum, sludge, and organic matter, thus reducing the load of impurities before secondary treatment.

[0011] Yet another object of the present invention is to develop a system capable of promoting groundwater recharge and reduce surface runoff through effective greywater treatment and soil infiltration.

[0012] The foregoing and other objects, features, and advantages of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.

SUMMARY OF THE INVENTION

[0013] The present invention relates to a soak pit system for the treatment and infiltration of household greywater that requires less cost and land resources while enhancing the longevity of grey water management solutions. The system comprises a cuboidal collection tank and three cylindrical chambers, facilitating effective filtration, treatment, and infiltration of grey water.

[0014] According to an embodiment of the present invention, a soak pit system for the treatment and infiltration of household greywater comprises of a cuboidal collection tank designed to collect greywater from household sources such as kitchens and bathrooms. This tank is engineered to ensure a hydraulic retention time of at least thirty minutes, which facilitates the settling of suspended solids. It includes a T-shaped dip pipe with a coarse filter, which has a larger diameter than other inlet pipes (115), effectively removing oil, grease, and grit. The filtered greywater is then directed to the first cylindrical chamber, which serves as the primary treatment unit. This chamber, constructed from a plastic barrel or tank, uses an inlet discharge pipe with a T-joint to minimize turbulence and contains four T-shaped dip pipes for the outflow. The chamber holds at least half of the daily average greywater discharge and have at least 6 hours hydraulic retention time which allows scum, sludge, and organic matter to settle, reducing the load of impurities in the water before it flows into the second cylindrical chamber.

[0015] According to another embodiment of the present invention, the proposed system further comprises of a second cylindrical chamber, made of precast concrete, provides secondary treatment with a capacity four times that of the daily average greywater discharge, allowing for a two-day hydraulic retention time. The bottom of this chamber features a layered filtration system with a 15 cm sand layer and a 15 cm pea gravel layer, further enhancing filtration. This chamber also serves as a temporary storage tank during clogging events, ensuring continuous treatment. Treated greywater then exits through four T-shaped dip pipes at the top and moves to the dispersion and infiltration chamber. This final chamber ensures the infiltration rate exceeds the daily average discharge rate and features a layered filtration system of sand, pea gravel, and coarse gravel. It is covered with a sealed concrete lid to prevent rainwater ingress and has a cemented structure above for added protection. The treated greywater percolates through these layers, evenly dispersing into the soil, promoting groundwater recharge, and reducing surface runoff. The entire system is designed for periodic maintenance, with a sealed concrete lid for easy access to primary and secondary chambers for de-sludging and filter replacement every two years, ensuring long-term efficiency and environmental compliance.

[0016] While the invention has been described and shown with particular reference to the preferred embodiment, it will be apparent that variations might be possible that would fall within the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
[0018] Figure 1 illustrates a top view of a soak pit system;
[0019] Figure 2 illustrates a first cylindrical chamber of a soak pit system;
[0020] Figure 3 illustrates a second cylindrical chamber of a soak pit system; and
[0021] Figure 4 illustrates an isometric view of dispersion and infiltration chamber of a soak pit system

DETAILED DESCRIPTION OF THE INVENTION

[0022] The following description includes the preferred best mode of one embodiment of the present invention. It will be clear from this description of the invention that the invention is not limited to these illustrated embodiments but that the invention also includes a variety of modifications and embodiments thereto. Therefore, the present description should be seen as illustrative and not limiting. While the invention is susceptible to various modifications and alternative constructions, it should be understood, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.

[0023] In any embodiment described herein, the open-ended terms "comprising," "comprises," and the like (which are synonymous with "including," "having" and "characterized by") may be replaced by the respective partially closed phrases "consisting essentially of," consists essentially of," and the like or the respective closed phrases "consisting of," "consists of, the like.

[0024] As used herein, the singular forms "a," "an," and "the" designate both the singular and the plural, unless expressly stated to designate the singular only.

[0025] The present invention relates to a soak pit system for the treatment and infiltration of household greywater designed to effectively filters and treats greywater from various household sources such as kitchens and bathrooms, promoting environmentally friendly disposal while minimizing maintenance and space requirements.

[0026] Figure 1 illustrates a top view of a soak pit system;


[0027] Figure 2 illustrates a first cylindrical chamber of a soak pit system;

[0028] Figure 3 illustrates a second cylindrical chamber of a soak pit system; and

[0029] Figure 4 illustrates an isometric view of dispersion and infiltration chamber of a soak pit system

[0030] The system begins with a cuboidal collection tank (110). This tank (110) is specifically designed to collect greywater from multiple household sources (115), including kitchens and bathrooms. The tank (110) is engineered to ensure a hydraulic retention time of at least thirty minutes, which is crucial for the initial settling of suspended solids. This prolonged retention time allows for the effective separation of larger particles and initial filtration.

[0031] To enhance the filtration process, the collection tank (110) incorporates a T-shaped dip pipe (120) with a coarse filter (125). This pipe (120) is designed with a larger diameter compared to other inlet pipes (115) in the tank (110), ensuring efficient removal of oil, grease, and grit from the greywater. The filtered water is then directed towards the soak pit (135) for further treatment.

[0032] The cuboidal collection tank (110) is designed to collect greywater from various household sources (115) such as kitchens and bathrooms. It is sized to ensure a hydraulic retention time of at least thirty minutes, which allows suspended solids to settle. The tank (110) includes a T-shaped dip pipe (120) with a coarse filter (125), which has a larger diameter than the other inlet pipes (115). This design effectively removes oil, grease, and grit from the greywater.

[0033] As the greywater enters the tank (110), the T-shaped dip pipe (120) and coarse filter (125) system trap and separate these contaminants, allowing the filtered greywater to flow smoothly into the next stage of the soak pit system. This initial filtration step is crucial in reducing the load of impurities entering the subsequent treatment chambers, thereby enhancing the overall efficiency and effectiveness of the soak pit system

[0034] The first cylindrical chamber is constructed from a plastic barrel or tank (210) and is equipped with a secure lid. This chamber serves as the primary treatment unit, where the initial filtration and settling of scum, oil, grease, surfactants, sludge, and organic matter occur.

[0035] An inlet discharge pipe with a T-joint (140) is used to introduce greywater into the chamber. This T-joint (140) is specifically designed to minimize turbulence during the inflow process, ensuring that the settling of suspended solids is not disturbed.

[0036] The chamber contains four T-shaped dip pipes (120), each with a dip length of half the height of the tank (110). These dip pipes (120) facilitate the outflow of pre-treated water from the top of the chamber, where the scum layer is least likely to interfere, directing it into the second cylindrical chamber.

[0037] The first cylindrical chamber acts as the primary treatment unit in the soak pit system, playing a crucial role in the initial filtration of greywater. Constructed from a plastic barrel or tank (210) and equipped with a lid, this chamber is designed to hold at least half of the daily average greywater discharge. Greywater enters the chamber through an inlet discharge pipe (130) fitted with a T-joint (140), which minimizes turbulence and allows for a smoother flow, facilitating the settling process. Inside the chamber, four T-shaped dip pipes (120) with a dip length of half the tank's height are positioned at the top to enable the outflow of pre-treated water.

[0038] As greywater settles in the chamber, scum (comprising oil, grease, and surfactants) rises to the surface, while sludge and other organic matter settle at the bottom. This primary filtration process significantly reduces the amount of solid waste and contaminants in the greywater. The cleaner, pre-treated greywater then flows out through the T-shaped dip pipes (120) to the second cylindrical chamber for further treatment. This primary treatment stage is essential for improving the overall efficiency and effectiveness of the soak pit system, as it helps to prevent clogging and ensures that subsequent treatment stages handle less contaminated water

[0039] The second cylindrical chamber is constructed from precast concrete, providing robust structural integrity. This chamber serves as the secondary treatment unit and is designed to hold four times the capacity of the daily average greywater discharge, allowing for a two-day hydraulic retention time.

[0040] The bottom of this chamber features a layered filtration system consisting of a 15 cm sand layer (430) and a 15 cm pea gravel layer (320). These layers enhance the secondary treatment by providing additional filtration and settling space for suspended solids.

[0041] This chamber also acts as a temporary storage tank during clogging events, ensuring the continuous treatment of greywater even when maintenance is required.

[0042] Four T-shaped dip pipes (120) at the top of the chamber facilitate the outflow of further treated greywater, directing it into the dispersion and infiltration chamber.

[0043] The second cylindrical chamber functions as the secondary treatment unit in the soak pit system. Constructed from precast concrete, this chamber has four times the capacity of the daily average greywater discharge, providing a two-day hydraulic retention time. This extended retention allows for further settling of suspended solids and additional treatment of greywater. At the bottom of the chamber, a layered filtration system consisting of a 15 cm sand layer (430) and a 15 cm pea gravel layer (320) enhances the secondary treatment by filtering out finer particles and facilitating the settling of any remaining impurities.

[0044] During normal operation, greywater flows from the primary chamber into this secondary chamber, where it undergoes additional filtration and settling. The chamber also serves as a temporary storage tank during clogging events, ensuring continuous treatment. The treated greywater then exits through four T-shaped dip pipes (120) at the top of the chamber, ready to move on to the final dispersion and infiltration stage. This thorough secondary treatment process ensures that the greywater is adequately filtered before it infiltrates the soil, maintaining the efficiency and effectiveness of the entire soak pit system

[0045] The final component of the system is the dispersion and infiltration chamber, designed to ensure that the infiltration rate from its outer curved surface area exceeds the daily average discharge rate.

[0046] The bottom of the chamber features a layered filtration system, comprising sand (430), pea gravel, and coarse gravel layers (320). These layers work together to provide optimal infiltration of treated greywater into the soil.

[0047] The chamber is covered with a sealed concrete lid (435) to prevent rainwater ingress. Additionally, a cemented structure above the chamber further ensures that rainwater entry is minimized, maintaining the integrity and efficiency of the greywater infiltration process.

[0048] The dispersion and infiltration chamber is the final stage in the soak pit system, responsible for the effective infiltration of treated greywater into the soil. This chamber is sized to ensure that its infiltration rate from the outer curved surface area exceeds the daily average discharge rate, thus preventing overflow and promoting efficient water dispersion. At the bottom of the chamber, a layered filtration system consisting of a sand layer (430), a pea gravel layer (320), and a coarse gravel layer further polishes the treated greywater by removing any remaining fine particles.

[0049] The chamber is covered with a sealed concrete lid (435) to prevent rainwater ingress, ensuring that only treated greywater enters the infiltration system. Additionally, a cemented structure above the chamber provides extra protection against rainwater entry. As the greywater percolates through these filtration layers, it is evenly dispersed and infiltrated into the surrounding soil, promoting groundwater recharge and preventing surface runoff. This final infiltration process ensures that the treated greywater is safely and efficiently returned to the environment, maintaining the integrity and sustainability of the soak pit system.

[0050] The entire soak pit system is equipped and sealed with a concrete lid (435), which serves to control odors and prevent rainwater entry. This sealed lid (220) design allows for periodic access to both the primary and secondary chambers for maintenance purposes. Regular de-sludging and filter replacement, recommended every two years, ensure that the system remains effective and minimizes the risk of clogging.

[0051] The maintenance system of the soak pit (135) is designed to ensure long-term efficiency and functionality by facilitating easy access and regular upkeep. The entire soak pit (135), including the primary and secondary treatment chambers, is equipped with a sealed concrete lid (435). This lid (220) serves multiple purposes: it controls odors, prevents rainwater entry, and provides secure coverage to prevent accidental ingress of debris or animals. Importantly, the sealed lid (220) is designed to be easily removable, allowing for periodic access to the chambers.

[0052] Regular maintenance activities, such as de-sludging and filter replacement, are recommended every two years to prevent clogging and ensure optimal performance. During maintenance, accumulated sludge and other residues can be removed from the primary and secondary chambers, and any worn-out filtration materials can be replaced. This proactive maintenance approach not only extends the lifespan of the soak pit system but also enhances its overall efficiency in treating and infiltrating greywater, thereby ensuring sustainable operation and environmental compliance

[0053] Although the field of the invention has been described herein with limited reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention.

, Claims:We Claim:
1) A soak pit system for the treatment and infiltration of household greywater, comprising:
a) a cuboidal collection tank (110) designed to collect greywater from various household sources (115), including kitchens and bathrooms, wherein the tank (110) is sized to ensure a hydraulic retention time of at least thirty minutes for average daily greywater discharge, and further comprising a T-shaped dip pipe (120) with a coarse filter (125) integrated to remove oil, grease, and grit, allowing filtered greywater to flow into the soak pit (135);
b) a first cylindrical chamber for primary treatment, constructed from a plastic barrel or tank (210) equipped with a lid, comprising an inlet discharge pipe (130) with a T-joint (140) to minimize turbulence, containing four T-shaped dip pipes (120) with a dip length of half the height of the tank (110) at the top for outflow, designed to hold at least half of the daily average greywater discharge, with the primary function of filtering scum and settling sludge and organic matter, wherein outflow is facilitated through the four T-shaped dip pipes (120) into the second chamber (310);
c) a second cylindrical chamber for secondary treatment, made of precast concrete, having four times the capacity of the daily average greywater discharge, comprising four T-shaped dip pipes (120) at the top for outflow, and equipped with a layered filtration system at the bottom including a 15 cm sand layer (430) and a 15 cm pea gravel layer (320), functioning as a secondary treatment unit and temporary storage tank during clogging events, and providing a two-day hydraulic retention time for further settling of suspended solids;
d) a dispersion and infiltration chamber sized to ensure the infiltration rate from the outer curved surface area exceeds the daily average discharge rate, featuring a layered filtration system at the bottom including a sand layer (430), a pea gravel layer (320), and a coarse gravel layer, covered with a sealed concrete lid (435) to prevent rainwater ingress, and designed for optimal infiltration of treated greywater into the soil, with a cemented structure above to prevent rainwater entry; and
e) a maintenance system wherein the whole soak pit (135) is equipped and sealed with a concrete lid (435) to control odours and prevent rainwater entry, with the sealed lid (220) allowing for periodic access to the primary and secondary chambers for de-sludging and filter replacement every two years.
2) The system as claimed in claim 1, wherein said T-shaped dip pipe (120) in the cuboidal collection tank (110) has a larger diameter than the other inlet pipes (115) to facilitate the removal of oil, grease, and grit more effectively.
3) The system as claimed in claim 1, wherein said first cylindrical chamber's inlet discharge pipe (130) with a T-joint (140) is specifically designed to minimize turbulence, thereby enhancing the primary filtration process.
4) The system as claimed in claim 1, wherein said second cylindrical chamber's layered filtration system includes a 15 cm sand layer (430) and a 15 cm pea gravel layer (320) at the bottom to enhance the secondary treatment of greywater.
5) The system as claimed in claim 1, wherein said dispersion and infiltration chamber is covered with a sealed concrete lid (435) and built with a cemented structure above to prevent rainwater entry, thereby maintaining the integrity and efficiency of the greywater infiltration process.
6) The system as claimed in claim 1, wherein said system is designed to be cost-effective by eliminating the need for a separate septic tank and requiring less space compared to conventional systems.
7) The system as claimed in claim 1, wherein said maintenance system allows for periodic access to the primary and secondary chambers for de-sludging and filter (125) replacement every two years, thereby minimizing clogging and facilitating maintenance.
8) The system as claimed in claim 1, wherein said system is environmentally friendly by promoting proper greywater treatment and infiltration into the soil, contributing to groundwater recharge and reducing surface runoff.

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