Device for treatment of domestic wastewater

Abstract

FIELD: domestic wastewater treatment.SUBSTANCE: invention relates to soil filters, botanical sites, treatment facilities based on a year-round greenhouse, treatment facilities based on aquaculture, devices for filtering, storing and disposing of purified water, heat accumulators and can be used in the treatment of domestic wastewater from isolated facilities and individual residential buildings. The device consists of a filter-equalizer 2, an anaerobic biofilter 3, a heat accumulator 4, an internal soil-plant filter 5, a heat exchanger 6, a vermicomposter 7 and a directly connected rotary receiving tray 8 for black runoff, a receiver of the liquid fraction of black runoff 9, combined tanks for aquaculture 10 and 11, and a container 12, all located in a heat-insulated room 1. A soil-plant filter 13 is located outside. The filter 13 is divided into sectors by solar collector panels. The device comprises a reservoir with plantings of aquatic plants 17, connected by a drainage channel to a biofilter 3. Above the sloping bottom of the vermicomposter 7 there is a grid with 2-3 mm holes, onto which a substrate with worms is applied. Trays 8 are equipped with a mesh with 2-5 mm holes on top.EFFECT: acceleration of composting, reduction of energy consumption of the device in cold climate conditions and provision of optimal temperature conditions for processes at any time of the year.2 cl, 4 dwg

Description

[0001] The invention relates to devices for treating domestic wastewater, including: soil filters, botanical sites, treatment facilities based on a year-round greenhouse, treatment facilities based on aquaculture, devices for filtering, storing and disposing of purified water, heat accumulators and can be used for decentralized treatment of domestic wastewater from separately located facilities.

[0002] The effectiveness of biological treatment of domestic wastewater is achieved through complex physical, chemical, and biological processes occurring in the soil and aqueous phase, and the disposal of purified water and valuable components with the greatest possible benefit is achieved through their use in agriculture and housing and communal services.

[0003] A device for treating highly concentrated wastewater from livestock farms is known (patent SU 1806102, 1991, C02F11 / 02; C02F11 / 04). The bioenergy system includes a collector of wastewater from equalization tanks, a methane tank, a gas holder, and a biogas boiler unit. Digested and disinfected wastewater is mechanically separated into solid and liquid fractions. The solid fraction is used in agriculture, and the liquid fraction enters a two-section storage pond. In the pond system, the liquid fraction of the digested wastewater is biologically purified to technically clean water and returned to the production cycle via a recirculation unit. A botanical garden is provided to prevent eutrophication of the reservoirs.

[0004] However, the current device is not designed to process household waste from residential buildings and also uses expensive, fire-hazardous equipment to accumulate and utilize the gas released from the digester. Meanwhile, the need for affordable, energy-efficient, and environmentally sound technologies for treating wastewater from residential buildings and other public facilities is long overdue.

[0005] The closest to the claimed solution is a device for treating domestic wastewater (RU Patent No. 2327648, 2006, C02F3 / 32, C02F11 / 04), consisting of a heated room and a filter-averager, an anaerobic biofilter, an internal soil-plant filter (botanical area), an intermediate tank, pipelines for supplying water to the soil-plant filters, as well as an external inclined soil-plant filter and a reservoir connected by a drainage channel to the anaerobic biofilter, characterized in that the heated room is heat-insulated. It houses a composter, a receiver for the liquid fraction of black runoff (black runoff is a mixture of grey and toilet waste) and communicating tanks for aquaculture, one of which connects an anaerobic biofilter with an averaging filter connected through an intermediate tank to an inclined external soil-plant filter divided into sectors.

[0006] The device uses an autonomous wastewater treatment system from an individual house based on equipment located in a thermally insulated room, designed for the biological treatment of black runoff, including liquid treatment in soil-plant filters and in the anaerobic bioreactor zone, as well as year-round composting of the solid fraction of the runoff by microbiota in a biocomposter.

[0007] Meanwhile, it is known that microbiota composting occurs at a slow rate in several stages with different temperature regimes. This complicates process optimization and reduces efficiency.

[0008] Technical result: simplification of the composting method and increased speed by replacing the microbial composting of organic waste from residential buildings with worm composting. Energy consumption is reduced by treating solid waste sludge with worms at residential temperatures, which ensures optimal temperatures for vermicomposting year-round, and the functionality of the wastewater treatment system is expanded.

[0009] The technical result is achieved in that in a device for processing domestic wastewater, consisting of a heated, thermally insulated room and located therein, a pipe for feeding black runoff from a septic tank, a vermicomposter equipped with inclined rotary trays for separating various fractions of black runoff, an averaging filter, an anaerobic biofilter, a heat accumulator, an internal soil-plant filter, an intermediate tank, pipelines for feeding water to the soil-plant filters, a receiver for the liquid fraction of black runoff and communicating tanks for aquaculture, one of which connects the anaerobic biofilter to the averaging filter connected through an intermediate tank to an inclined external soil-plant filter divided into sectors, located on the roof of the room, as well as a reservoir connected by a drainage channel to the anaerobic biofilter, according to the invention, a grate with openings is located above the inclined bottom of the vermicomposter 2-3 mm,In this case, a layer of substrate with worms is applied to the grid, the sectors of the external soil-plant filter are separated by solar collector panels, and the heat removed from the solar collectors is supplied to heat the internal heat accumulator, the soil-plant filters are prepared on the basis of biohumus obtained in a vermicomposter, the inclined rotary trays on top are equipped with a mesh with 2-5 mm holes.

[0010] The technical result is achieved due to the fact that the processing of solid waste is carried out by worms in a vermicomposter, which does not exclude composting in the combined presence of worms and microorganisms, for example, in the mesophase of composting.

[0011] The technical result is also achieved due to the fact that the effluent comes from the septic tank after being stirred up and homogenized using a vortex device in a state that is optimally suitable for processing by worms.

[0012] The efficiency of domestic wastewater treatment is achieved due to the fact that the treatment of the solid organic fraction of the wastewater by worms after processing in a septic tank significantly reduces the energy intensity of the processes, since the worms are active in the range of room temperatures, which are maintained in a thermally insulated room.

[0013] The efficiency of wastewater treatment is achieved due to the fact that the treatment of the solid organic fraction of the wastewater with worms after the treatment of the wastewater using a vortex device significantly reduces the time of waste processing.

[0014] The efficiency of wastewater treatment is achieved by eliminating operations associated with pre-treatment of solid waste outside the wastewater treatment system (fine grinding of waste and exposure to conditions conducive to decomposition).

[0015] The efficiency of heat saving consists in reducing the energy consumption of the device by treating wastewater in a heat-insulated room located in the semi-basement, which significantly reduces heat loss under wind load.

[0016] Well-organized use of solar energy concentrators allows for additional heating of an insulated room and the equipment located in it.

[0017] Fig. 1 shows a block diagram of the proposed device (without a vortex device), Fig. 2 shows the layout of the device units (side view), Fig. 3 shows a diagram of the combination of a vermicomposter with a black runoff fractionation unit, and Fig. 4 shows the structure of an external soil-plant filter divided into sectors.

[0018] The device (Fig. 1) consists of a filter-averager 2, an anaerobic biofilter 3, a heat accumulator 4, an internal soil-plant filter 5, a heat exchanger 6, a vermicomposter 7 and directly connected to it inclined rotary trays 8 for separating black runoff into fractions, a receiver of the liquid fraction of black runoff 9, combined tanks for aquaculture 10 and 11, an intermediate tank 12, as well as sectors of a soil-plant filter 13, an underground gravity drainage channel 14, a water accumulator 15, a sand filter 16 and a reservoir with plantings of aquatic plants 17, all located outside.

[0019] Filter loading 5 is located on a non-filtering base with a heat exchanger 6, through which warm waste water from the averaging filter 2 is supplied to the filter.

[0020] Anaerobic biofilter 3 is a space filled with a bed of any suitable material that serves as a carrier of anaerobic microflora, for example, gravel with evenly distributed particles of sand and zeolite-containing rock or individual free-floating fractions of porous synthetic material.

[0021] Anaerobic biofilter 3 contains at least one cavity—collector 18 (Fig. 2)—designed to accumulate treated wastewater. Biofilter 3 is connected to filter-averaging 2 via aquaculture tank 10. The volume of biofilter 3 receiving water is set to approximately equal to the ten-day volume of water used by the consumer. This ensures sufficient water storage time for the death of the bulk of pathogenic microflora and satisfies the water conditioning regime for the composition of anaerobic filter 3, as well as aquaculture tanks 10 and 11.

[0022] Anaerobic biofilter 3 has the properties of a water heat accumulator and therefore it can be combined with any other heat accumulator.

[0023] Figure 1 shows two aquaculture tanks 10 and 11. In practice, the number of tanks is limited primarily by their placement within the greenhouse. It is envisaged that there will be at least two aquaculture tanks, interconnected in such a way that one tank can serve as an intermediate tank connecting the filter-averaging tank 2 and the anaerobic biofilter, and the other as a storage tank for purified water.

[0024] The unit for separating turbid black runoff is shown schematically in Fig. 2 (highlighted in gray) and Fig. 3. It includes a vermicomposter tank 7 and inclined rotating trays 8. A mesh with 2-5 mm holes is located above the bottom of the trays. When full, the trays tip over and dump the solid fraction into the vermicomposter tank 7, and excess liquid flows into the liquid fraction receiver 9 of the black runoff due to the tilt of the tray.

[0025] The vermicomposter is an elongated container running along rotating trays. A grate with 2-3 mm holes is located above the bottom of the vermicomposter. A layer of substrate containing worms is applied to the grate. Due to the slope of the vermicomposter's bottom, excess liquid from the vermicomposter drains into a black runoff receiver 9. The vermicomposter can also be equipped with additional sections for both vermicompost removal and optimization of worm life, such as feeding or population control.

[0026] The structure of the external soil-plant filter 13 is shown in Fig. 4.

[0027] This filter consists of functionally distinct sectors, arranged on the sloping roof of a recessed, insulated room. One sector is used to relieve peak loads and can be activated when any of the operating sectors is shut down for drying. Ventilation ducts (19) are installed within the external filter media. The media of the soil-plant filters, which are used to grow specially selected plants that utilize water and impurities, is prepared using vermicompost. The media and vegetation of the external soil-plant filter also serve as insulation for the insulated room.

[0028] The plants on this filter are planted so that they create transverse furrows at the bottom, preventing the intense flow of water into a pond 17 with aquatic plants located at the base of the filter. The opposite edge of the pond is lined with earth. This increases its capacity to accommodate excess water. Purified water enters storage tank 15 through sand filter 16.

[0029] The black runoff separation unit operates as follows. The black runoff, stirred up by a vortex device, enters inclined rotating trays 8 from above the vermicomposter 7, located in a heat-insulated room. The liquid fraction flows through a mesh into a liquid receiver 9 (Fig. 2), and the solid fraction, after the trays are turned around their axis, falls onto the substrate of the vermicomposter 7.

[0030] Winter Mode. In winter mode, wastewater is primarily treated in a thermally insulated room, and excess treated water is pumped into an outdoor body of water. Treatment is performed as follows.

[0031] Wastewater from liquid receiver 9 is fed through intermediate tank 12 to filter-equalizer 2. Here, it is conditioned to the specified compositional characteristics and fed through heat exchanger 6 to soil-plant filter 5. The bulk of the water passes through filter 5 into anaerobic biofilter 3. From biofilter 3, the water is fed to aquaculture tanks and from tank 10, it enters filter-equalizer 2 through a special inlet device. The inlet device is designed in such a way that it only allows water to enter.

[0032] This cycle occurs naturally because, due to icing, water from biofilter 3 cannot exit into storage tank 15. Water moves between individual units by gravity, which occurs either when it enters filter-averaging 2 or when purified water is withdrawn from tank 11. Excess purified water is discharged into storage tank 15 by periodically breaking through the ice or using a pump.

[0033] Summer Mode. In the summer mode, the bulk of the wastewater is processed in external water treatment units. Wastewater from tank 9 is fed to filter-equalizer 2. Here, it is conditioned to the specified compositional characteristics and then fed through tank 12 to one of the sectors of external soil-plant filter 13, saturating it and partially evaporating. The bulk of the water from tank 9, after being diluted with water from the filter-equalizer in tank 12, passes through filter 13 and enters reservoir 17, from where it then flows through sand filter 16 to water storage tank 15. This is facilitated by a specially selected ratio of liquid levels in the device's units located inside and outside the insulated room.

[0034] Plants in reservoir 17 and storage tank 15 are a powerful additional factor processing wastewater impurities. Processing occurs in the root zone, where a biological eco-community is formed, including plant roots and microorganisms that actively interact with impurities. The plants directly absorb some impurities from the water. Particularly attractive is the tropical plant water hyacinth, which can significantly reduce pollution levels. For example, according to [CLR Pinto, LTP Poladino, BP Jorge, AC Guimaraes. In Managing the Wastewater Resource. Proceedings of the 4th International Conference on Ecological Engineering for Wastewater Treatment. at As, Norway, 1999], cultivating hyacinth can reduce the BOD of domestic wastewater by 90%.

[0035] Water conditioning consists in the fact that small volumes of water coming from the filter-averager 2 through the soil-plant filter 5 into the storage tank 15 are distributed in significantly larger volumes of water circulating in a closed chain: soil-plant filter - water storage tank - reservoir with aquatic vegetation - drainage channel - anaerobic biofilter and are subjected to the purification processes occurring in these units of the device.

[0036] Step-by-step conditioning of the water composition in the filter-averager, as well as in the anaerobic filter, helps to bring its characteristics as close as possible to the characteristics of the root fluid of plants for the selected biocenosis of the soil-plant filter, increasing the efficiency of the device.

[0037] The proposed organization of the operation of soil-plant filters allows for achieving their maximum water saturation, sufficient supply of water to plants and its intensive evaporation from the surface of the filters and plant foliage.

[0038] The required quality of the treated water is achieved due to the fact that the water is repeatedly processed in the chain: soil-plant filter - reservoir with aquatic vegetation - underground drainage channel - anaerobic biofilter.

[0039] Thus, the proposed device for treating domestic wastewater can be used for cleaning, recycling and storing wastewater, as well as keeping heat-loving plants and worms in an insulated room during the cold period.

[0040] Thus, the proposed invention has broader functional capabilities, accelerates the process of composting solid household organic waste, reduces the energy consumption of the device for cleaning household waste in cold climates and ensures an optimal temperature regime for technological processes at any time of the year.

Claims

1. A device for treating domestic wastewater, consisting of a heated, insulated room and, located therein, a pipe for feeding black runoff from a septic tank, a vermicomposter equipped with inclined rotary trays for separating various fractions of black runoff, an averaging filter, an anaerobic biofilter, a heat accumulator, an internal soil-plant filter, an intermediate tank, pipelines for feeding water to the soil-plant filters, a receiver for the liquid fraction of black runoff and communicating tanks for aquaculture, one of which connects the anaerobic biofilter to the averaging filter connected through an intermediate tank to an inclined external soil-plant filter divided into sectors, located on the roof of the room, as well as a reservoir connected by a drainage channel to the anaerobic biofilter, characterized in that a grate with 2-3 mm holes is located above the inclined bottom of the vermicomposter, while a layer of substrate is applied to the grate with worms,The sectors of the external soil-plant filter are separated by solar collector panels, and the heat removed from the solar collectors is supplied to heat the internal heat accumulator; the soil-plant filters are prepared on the basis of biohumus obtained in a vermicomposter; the inclined rotating trays are equipped with a mesh with 2-5 mm holes on top.

2. A device for treating domestic wastewater according to paragraph 1, characterized in that the solid fraction of black wastewater comes from the septic tank after being stirred up and homogenized using a vortex device capable of operating in mechanical mixing and cavitation modes.

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