Purification treatment system and purification treatment method

Abstract

To provide a purification treatment system and a purification treatment method which perform solid-liquid separation by a filtration film in an acidic state and an anaerobic state, and thereby produce circulatable washing water.SOLUTION: A purification treatment system 1 for purifying treated water 13 containing dirt, and circulating the purified treated water as washing water includes a raw water tank 22 to which the treated water 13 containing liquid dirt and / or crushed solid dirt is charged, and a washing water tank 24 which is arranged on a side closer to a rear stage side than the raw water tank 22, and stores the treated water purified by the raw water tank 22 as washing water for washing new dirt, wherein in the raw water tank 22, the charged treated water 13 is kept in acidic and anaerobic states, and solid-liquid separation by a filtration film 31 arranged in the raw water tank 22 is performed on the treated water 13.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a purification treatment system that purifies wastewater and circulates the purified water as cleaning water. [Background technology]

[0002] As technologies relating to toilet systems using the MBR (Membrane Bio Reactor) method, for example, the technologies shown in Patent Documents 1 to 3 are disclosed. The technology shown in Patent Document 1 is a flush toilet system having a raw material tank for storing biogas raw material, a second wastewater treatment means for separating wastewater generated during toilet use into grey water and sludge, a fermenter for fermenting the biogas raw material and the sludge to generate biogas, a pump for supplying grey water to the toilet, and a generator for generating electricity using the biogas and supplying the electricity to the second wastewater treatment means and the pump, and the second wastewater treatment means is configured to treat wastewater using a membrane separation activated sludge method.

[0003] The technology shown in Patent Document 2 is a sewage treatment method using a biological treatment circulation system that utilizes a membrane separation method, in which wastewater from toilets is circulated in the following order: solid-liquid separation tank → membrane separation intermittent aeration tank → decolorization tank → storage tank → toilet, solids are removed in the solid-liquid separation tank by natural sedimentation and filter media, aeration is carried out intermittently in the membrane separation intermittent aeration tank in which a membrane separation device is immersed and where activated sludge treatment is carried out, nitrification and denitrification proceed, the filtered permeate is sent to the decolorization tank by an air lift pump, and decolorized treated water is sent to the storage tank, from which it is supplied to the toilet as flush water.

[0004] Patent Document 3 discloses a membrane-based water circulation system that supplies water to a water usage space that is divided into a water usage area, a water usage area, and a flush toilet area based on the water quality acceptance standards of the supply water, in which drinking water is supplied to the water usage area, purified and regenerated water is supplied to the water usage area and the flush toilet area, wastewater and sewage discharged from the water usage area and the water usage area, respectively, are treated in a membrane separation activated sludge device, the permeated water extracted from the membrane separation activated sludge device is treated in a reverse osmosis membrane device or a nanofiltration membrane device, the permeated water extracted from the reverse osmosis membrane device or the nanofiltration membrane device is supplied to the water usage area, and concentrated water extracted from the reverse osmosis membrane device or the nanofiltration membrane device is supplied to the flush toilet area. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-012340 A [Patent Document 2] JP 2008-86991 A [Patent Document 3] JP 2007-130567 A Summary of the Invention [Problem to be solved by the invention]

[0006] The MBR method is a method in which organic matter in the treatment liquid is decomposed by microorganisms present in activated sludge, and the activated sludge is filtered through a filtration membrane to extract treated water. When the MBR method is carried out, as shown in Patent Documents 1-3, oxygen is supplied to the microorganisms in the activated sludge by aeration treatment to activate the microorganisms, and solids that have clogged the filtration membrane are removed by the force of air pressure, water pressure, etc. generated by aeration.

[0007] However, in an environment with sufficient oxygen and nutrients, there is a problem that the activated sludge grows too much and clogs the filtration membrane.In addition, the aeration process causes relatively hard-to-decompose solid matter to constantly float in the water, which causes the solid matter to clog the filtration membrane.

[0008] Furthermore, in order to recycle and reuse water used in toilets and other facilities, it is necessary to produce flushing water that is hygienic and safe. This usually involves multiple stages of biological treatment (aerobic and anaerobic treatment). However, performing multiple stages of biological treatment requires large equipment and long processing times.

[0009] Furthermore, a blower needs to be operated to perform the aeration treatment, which requires a large amount of electricity. Therefore, if the system is to be installed in a location where there is no commercial power source, such as a mountainous region, it is necessary to prepare large secondary batteries, etc., which results in the problem of the system becoming larger and increasing costs.

[0010] The present invention has been made to solve the above-mentioned problems, and aims to provide a purification treatment system and a purification treatment method that generate circulatable cleaning water by performing solid-liquid separation using a filtration membrane under acidic and anaerobic conditions. [Means for solving the problem]

[0011] The purification treatment system of the present invention is a purification treatment system that purifies treated water containing sewage and circulates it as cleaning water, and is equipped with a raw water tank into which the treated water containing liquid sewage and / or crushed solid sewage is fed, and a cleaning water tank arranged downstream of the raw water tank and storing the treated water purified in the raw water tank as cleaning water for washing new sewage, in which the fed water is maintained in an acidic and anaerobic state, and the treated water undergoes solid-liquid separation using a filtration membrane arranged in the raw water tank.

[0012] In this way, the purification treatment system of the present invention comprises a raw water tank into which the water to be treated containing liquid sewage and / or pulverized solid sewage is fed, and a cleaning water tank arranged downstream of the raw water tank in which the water to be treated that has been purified in the raw water tank is stored as cleaning water for washing new sewage.In the raw water tank, the water to be treated that is fed therein is maintained in an acidic and anaerobic state, and solid-liquid separation is performed on the water to be treated using a filtration membrane arranged in the raw water tank.By not performing aerobic treatment, an acidic state is maintained and the growth of bacteria is suppressed, thereby achieving the effect of producing hygienic and safe treated water that can be recycled as cleaning water.

[0013] In other words, by making the water to be treated acidic, it is possible to eliminate general bacteria that grow in neutral conditions and bacteria that become activated sludge, and to purify the water by decomposing organic matter, etc. with anaerobic bacteria while suppressing the growth of activated sludge. At this time, the inventors' experiments made it clear that it is possible to obtain hygienic and highly safe treated water that can be recycled as cleaning water by decomposing organic matter, etc. with anaerobic bacteria.

[0014] In addition, because the raw water tank is maintained in an anaerobic state, suspended matter and the like do not float in the water to be treated, so the filter membrane is less likely to become clogged. Furthermore, because wash water is produced simply by performing solid-liquid separation in the anaerobic treatment, the purification process can be simplified, making the equipment more compact and shortening the treatment time, and because aeration treatment is no longer necessary, power consumption can be reduced. [Brief description of the drawings]

[0015] [Figure 1] 1 is a system outline diagram of a purification processing system according to a first embodiment. [Diagram 2] 1 is a system configuration diagram of a purification processing system according to a first embodiment. [Diagram 3] FIG. 11 is a system configuration diagram of a purification processing system according to a second embodiment. [Figure 4] FIG. 11 is a system schematic diagram of a purification processing system according to a third embodiment. [Diagram 5] FIG. 11 is a diagram showing the configuration of a raw water tank and an external tank in a purification treatment system according to a third embodiment. [Figure 6] FIG. 13 is a diagram showing the structure of a raw water tank in a purification treatment system according to a fourth embodiment. [Figure 7] FIG. 13 is a first diagram showing the structure of a raw water tank in a purification treatment system according to a fifth embodiment. [Figure 8] FIG. 13 is a second diagram showing the structure of the raw water tank in the purification treatment system according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] (First embodiment of the present invention) The purification treatment system according to this embodiment will be described with reference to Figures 1 and 2. The purification treatment system according to this embodiment is a circulation type purification treatment system that purifies treated water containing excrement when, for example, a person uses a toilet, and reuses it as washing water for new excrement. The purification treatment system according to this embodiment can be applied to purification facilities that purify livestock excrement and reuse water, in addition to toilets for humans. In the following embodiment, a purification treatment system for a toilet for humans will be described.

[0017] Fig. 1 is a system overview diagram of a purification treatment system according to this embodiment, and Fig. 2 is a system configuration diagram of the purification treatment system according to this embodiment. In Fig. 1 and Fig. 2, the purification treatment system 1 includes toilet rooms 10a, 10b for humans to relieve themselves, and a purification treatment unit 20 that purifies treatment water 13 containing excrement discharged into toilet bowls 11a, 11b of the toilet rooms 10a, 10b, toilet paper, and other waste. Although not shown in Fig. 1 and Fig. 2, pumps, valves, and the like described below are controlled by a control unit based on information measured by various sensors.

[0018] The toilet rooms 10a, 10b are each a private room, and are equipped with toilet bowls 11a, 11b where users can enter to relieve themselves, and flush tanks 12a, 12b that store flushing water for flushing excrement. The flush tanks 12a, 12b store flushing water sent from a purification treatment unit 20, which will be described later, but depending on the installation environment of the purification treatment system 1, they can also be configured to store clean water or grey water supplied from a public water supply or grey water supply (see the dashed line in FIG. 2).

[0019] Furthermore, the water to be treated 13, which contains excrement and other waste generated when water is flushed after excretion, is sent to a purification treatment unit 20, which will be described later, for purification treatment, but depending on the installation environment of the purification treatment system 1, it may be connected to a public sewerage system and discharged as sewage (see the dashed line in FIG. 2). The flow path of the water to be treated 13 is controlled by first motor valves 41a, 41b to determine whether it is discharged into the sewage system or sent to the downstream purification treatment unit 20. The first motor valves 41a, 41b are controlled manually or by a control unit based on preset setting information.

[0020] The purification treatment unit 20 includes a crushing pump 21 that crushes solid waste such as excrement and toilet paper contained in the water to be treated 13 and sends it to the next stage raw water tank 22 together with the water to be treated 13, a raw water tank 22 that decomposes organic matter in the water to be treated 13 and produces wash water by performing solid-liquid separation with a filtration membrane 31, an advanced treatment tank 23 that sterilizes the wash water produced in the raw water tank 22, a washing water tank 24 that stores the sterilized wash water, an activated carbon filter 25 that decolorizes and deodorizes the wash water stored in the washing water tank 24, a pressure tank 26 under pressure for sending the wash water to the washing tanks 12a and 12b, a chemical tank 27 that stores a chemical solution to be added when washing the filtration membrane 31 as necessary, and a water activator 28 that activates the wash water in the circulation passage when the wash water stored in the washing water tank 24 is returned to the advanced treatment tank 23 and circulated.

[0021] The water to be treated 13 discharged from the toilets 11a and 11b is sent together with liquid waste to the next stage, raw water tank 22, while solid matter such as excrement and toilet paper is crushed by the crushing pump 21. Since larger solid matter is crushed by this crushing pump 21, the water to be treated 13 containing fine solid matter, liquid waste, and washing water used during washing is fed into the raw water tank 22.

[0022] In the raw water tank 22, organic matter contained in the water 13 to be treated is decomposed while solid-liquid separation is performed by the filter membranes 31a and 31b. Anaerobic bacteria are always present in the raw water tank 22, and anaerobic treatment is performed by the anaerobic bacteria at the same time as the water 13 to be treated is introduced. In other words, aeration treatment using a blower or the like is not performed in the raw water tank 22. When the water 13 to be treated is introduced into the raw water tank 22, sludge derived from toilet paper, which is relatively easy to float, and sludge derived from human waste, which is suitable for anaerobic treatment, are deposited as separate layers near the bottom of the raw water tank 22, forming an environment in which anaerobic treatment is likely to proceed. Furthermore, the sludge derived from toilet paper can also function as a filter layer, which will be described in detail later in the fourth and fifth embodiments.

[0023] Also, at some timing during the time when the water to be treated 13 is introduced from the toilets 11a, 11b into the raw water tank 22 (for example, when the toilets 11a, 11b are flushed after a user uses the toilet), citric acid is introduced to make the water to be treated 13 acidic. By introducing citric acid, the water to be treated 13 in the raw water tank 22 becomes acidic. Specifically, the pH is adjusted to between 2.0 and 4.8. The timing and amount of citric acid to be introduced may be controlled by the control unit calculating appropriate introduction timing and amount according to the measurement result of pH in the raw water tank 22. Also, other than citric acid, for example, acetic acid, organic acid (for example, malic acid, etc.), carbonic acid, dilute hydrochloric acid, dilute sulfuric acid, hydrofluoric acid, phosphoric acid, etc. may be introduced.

[0024] That is, in the raw water tank 22, anaerobic treatment is performed under acidic and anaerobic conditions. Since the water 13 to be treated is acidic, the growth of bacteria such as Escherichia coli that grow well near neutral pH is suppressed, and the growth of activated sludge is suppressed, thereby preventing clogging of the filtration membrane 31. Furthermore, by making the water 13 to be treated acidic, a large amount of odorous components such as ammonia are dissolved, making it possible to suppress the generation of gas that causes odor. Furthermore, although details will be described in the second embodiment, by making the water 13 to be treated acidic, soluble substances such as minerals are easily dissolved, and it is possible to prevent the soluble substances from crystallizing and clogging the filtration membrane 31. In this embodiment, since decomposition of organic matter is performed by anaerobic treatment without aeration treatment, the pH does not increase due to aeration treatment, and an acidic state of pH 2.0 to 4.8 is maintained, making it possible to maintain the above-mentioned effects.

[0025] By the anaerobic treatment under the acidic condition described above, organic matter is decomposed, and cleaning water is generated from which general bacteria that grow in neutral conditions, including E. coli, have been removed. On the other hand, since persistent solid matter and the like tend to remain as suspended matter, the suspended matter and cleaning water are separated by solid-liquid separation using filtration membranes 31a and 31b (e.g., UF membrane). The cleaning water separated by the filtration membranes 31a and 31b has E. coli and the like removed as described above (already verified by the inventors' experiments) and becomes clear, highly permeable cleaning water (already verified by the inventors' experiments), so it can be reused as cleaning water as it is, but in order to obtain more hygienic and safer cleaning water, the following post-treatment is performed.

[0026] Normally, after a certain period of operation, periodic maintenance such as replacement of the filtration membrane 31 is required, but in the case of this embodiment, the filtration membrane 31 does not become clogged as long as the above-mentioned acidic and anaerobic conditions are maintained, and no maintenance is required.

[0027] In the post-treatment, the second motor valves 42a, 42b are opened manually or under the control of the control unit, and the solid-liquid separated cleaning water pumped up by the first pump 32 through the filtration membranes 31a, 31b is introduced into the advanced treatment tank 23. A first pressure sensor 43 is installed in the middle of the flow passage connecting the raw water tank 22 and the advanced treatment tank 23, and the control unit judges the degree of clogging of the filtration membranes 31a, 31b according to the measurement result of the first pressure sensor 43. That is, if the negative pressure of the first pressure sensor 43 is large, it is judged that the filtration membranes 31a, 31b may be clogged, and an alarm is issued to a manager who manages the system from a remote location. In the advanced treatment tank 23, sterilization and the like are performed using ozone (O3) to obtain more hygienic and safer cleaning water.

[0028] The cleaning water put into the advanced treatment tank 23 is sucked out by the second pump 33, ozone is added by the ozone adding section 51, and the cleaning water is returned to the advanced treatment tank 23. The cleaning water to which ozone has been added is free of bacteria, viruses, and other substances that can be removed by ozone, improving safety. While the cleaning water is retained in the advanced treatment tank 23, the second pump 33 is driven constantly, periodically, or irregularly to perform sterilization with ozone, thereby keeping the cleaning water in the advanced treatment tank 23 clean. The second pump 33 is driven manually or under the control of the control unit based on preset setting information. In addition, a first water level sensor 44 is installed in the advanced treatment tank 23, and when the water level of the first water level sensor 44 falls below a predetermined value, the control unit drives the first pump 32 to control the flow of cleaning water from the raw water tank 22 into the advanced treatment tank 23. Furthermore, when the water level of the first water level sensor 44 falls below a predetermined value, the control unit locks the third pump 34 described below, thereby controlling the pump 34 to prevent wash water from being sent from the wash water tank 24 to the pressure tank 26.

[0029] The advanced treatment tank 23 and the next-stage cleaning water tank 24 are connected by a flow passage below, and the cleaning water from the advanced treatment tank 23 naturally flows into and is stored in the cleaning water tank 24. In the advanced treatment tank 23, sterilization treatment is performed using ozone, and organic matter reacts with the ozone to generate bubbles, which can cause problems with the operation of the pump, etc. For this reason, here, the advanced treatment tank 23 and the cleaning water tank 24 are separated into separate tanks and connected by a flow passage below, preventing bubbles from flowing into the cleaning water tank 24 and allowing the cleaning water to be pumped up smoothly, etc.

[0030] The cleaning water stored in the cleaning water tank 24 is constantly or periodically or irregularly sucked up by the third pump 34 with the third motor valve 45 open, and returned to the advanced treatment tank 23 for circulation (flow path indicated by dotted line (1) in FIG. 2). A water activator 28 is provided midway along the flow path (1) along which the cleaning water is returned from the cleaning water tank 24 to the advanced treatment tank 23, and the cleaning water is returned to the advanced treatment tank 23 through this water activator 28. In other words, the cleaning water stored in the advanced treatment tank 23 and the cleaning water tank 24 is activated by the water activator 28 while being disinfected with ozone, etc., so the longer the storage time, the more hygienic and safe the cleaning water becomes.

[0031] Also, under the control of the control unit, the cleaning water in the cleaning water tank 24 is sucked up by the third pump 34 with the third motor valve 45 and fourth motor valves 48a, 48b described later closed, and filled into the pressure tank 26 (the flow path indicated by the dotted line in (2) in FIG. 2). A second pressure sensor 46 and a first flow rate sensor 47 are installed in this flow path indicated by the dotted line in (2), and the pressure and flow rate in the pipe are measured. If the pressure measured by the second pressure sensor 46 is decreasing, the control unit determines that the water level and pressure in the pressure tank 26 are decreasing, and drives the third pump 34 to supply cleaning water to the pressure tank 26. If the flow rate of the first flow rate sensor 47 is decreasing, the control unit determines that the water level and pressure in the pressure tank 26 have increased, making it difficult to supply cleaning water, and stops driving the third pump 34. An activated carbon filter 25 is disposed midway along flow path (2) along which flush water is sent from flush water tank 24 to pressure tank 26, where harmful substances are removed and deodorization is performed before the pressure tank 26 is filled. A first check valve 49 is disposed in this flow path to prevent flush water from flowing back from pressure tank 26 to flush water tank 24. When a user of toilet rooms 10a, 10b turns the lever of flush tank 12a, 12b, flush water stored in flush tank 12a, 12b is sent to toilet bowl 11a, 11b to flush, and flush water from pressure tank 26 is pressure-fed to flush tank 12a, 12b until it reaches a predetermined height and is stored as the next flush water.

[0032] Furthermore, under the control of the control unit, the cleaning water stored in the cleaning water tank 24 is sucked up by the third pump 34 periodically or irregularly with the third motor valve 45 closed and the fourth motor valves 48a, 48b open, and is returned to the raw water tank 22 by circulating the filtration membrane 31 in the reverse direction (flow path shown by dotted line (3) in FIG. 2). At this time, if the water level and pressure of the pressure tank 26 are low, cleaning water is also sent to the pressure tank 26. By returning the cleaning water to the raw water tank 22 through the flow path shown by dotted line (3), it is possible to remove clogging of the filtration membrane 31 by pressing the membrane from the reverse direction. At this time, the chemical solution (e.g., sodium hypochlorite, etc.) stored in the chemical solution tank 27 is pumped out by the fourth pump 35 installed in the chemical solution tank 27, and the chemical solution is added to the cleaning water while being returned to the raw water tank 22 (flow path shown by dotted line (4) in FIG. 2). In this way, the filtration membrane 31 can be sterilized with the chemical solution and made less likely to become clogged. A second check valve 50 is provided in the flow path of the chemical solution to prevent the chemical solution from flowing backward.

[0033] It should be noted that the system configuration of the purification treatment system 1 shown in Figures 1 and 2 is merely one example, and the purification treatment unit 20 must be configured to include at least the raw water tank 22 and a tank for storing cleaning water arranged downstream of the raw water tank 22.

[0034] 1 and 2, the purification treatment system 1 is described as having two toilet rooms 10a and 10b, but the number of toilet rooms may be one or more. Other components that are provided in general public toilets, such as a ventilation fan, a washbasin, an operation panel, and an emergency call button, can be installed as necessary.

[0035] As described above, the purification treatment system of this embodiment includes a raw water tank 22 into which the to-be-treated water 13 containing liquid sewage and / or pulverized solid sewage is fed, and a cleaning water tank 24 that is arranged downstream of the raw water tank 22 and stores the to-be-treated water 13 purified in the raw water tank 22 as cleaning water for washing the sewage. In the raw water tank 22, the to-be-treated water 13 fed therein is maintained in an acidic and anaerobic state, and solid-liquid separation is performed on the to-be-treated water 13 by a filtration membrane 31 arranged in the raw water tank 22. Therefore, while producing treated water that can be circulated as cleaning water, stable operation is possible without clogging the filtration membrane 31 with activated sludge by not performing aerobic treatment.

[0036] Furthermore, by adding citric acid when the water to be treated 13 is made acidic, it is possible to prevent the pH from becoming 2.0 or less, which is harmless, and to facilitate pH adjustment.

[0037] (Second embodiment of the present invention) The purification system according to this embodiment will be described with reference to Fig. 3. The purification system according to this embodiment is the purification system according to the first embodiment, except that it includes a water adding means for adjusting the concentration of the soluble substances in the raw water tank 22. Note that the description of this embodiment that overlaps with the first embodiment will be omitted.

[0038] FIG. 3 is a system configuration diagram of the purification treatment system according to this embodiment. In FIG. 3, a conductivity sensor 52 for measuring the conductivity in the raw water tank 22 and a rainwater tank 53 for storing rainwater as a water adding means are provided. As the number of times the toilet rooms 10a and 10b are used increases, the amount of water to be treated 13 fed into the raw water tank 22 increases. The water to be treated 13 contains waste discharged from the human body, and therefore contains a large amount of soluble substances such as minerals. If the amount of soluble substances in the water to be treated 13 in the raw water tank 22 increases too much and the water becomes saturated, the soluble substances precipitate and crystallize, causing an increase in scale. As a result, this causes clogging of the filtration membrane 31.

[0039] Therefore, in this embodiment, as described above, the water to be treated 13 in the raw water tank 22 is made acidic to increase the concentration limit of the soluble substances to make them less likely to crystallize, and the electrical conductivity in the raw water tank 22 is measured, and when the electrical conductivity reaches or exceeds a predetermined threshold, the soluble substances are diluted to prevent crystallization and prevent clogging of the filtration membrane 31. When the control unit receives the measurement result of the electrical conductivity sensor 52 and determines that the received electrical conductivity value is equal to or greater than a predetermined threshold (e.g., 20 mS / cm), the control unit drives the ninth pump 40 with the fifth motor valve 54 open, sends rainwater from the rainwater tank 53 to the raw water tank 22, and dilutes the soluble substances in the water to be treated 13 in the raw water tank 22. As a result, the soluble substances do not reach the concentration limit, so that it is possible to prevent the generation of scale and the clogging of the filtration membrane 31.

[0040] At this time, the amount of rainwater to be allowed to flow in may be a preset amount, or may be allowed to flow in until the real-time measurement result of the electrical conductivity sensor 52 falls below a predetermined threshold. Alternatively, the amount of water to be treated 13 may be calculated from the value of the second water level sensor 55 installed in the raw water tank 22, the concentration of soluble substances may be calculated from the measurement result of the electrical conductivity, and the amount of rainwater required to reduce the concentration of soluble substances to a predetermined value or less may be calculated based on these calculated values. These calculation processes, the control of the ninth pump 40, and the control of the fifth motor valve 54 are performed by the control unit.

[0041] In addition, since the amount of water stored in the rainwater tank 53 is affected by the weather, the manager may periodically or irregularly replenish the tank with water other than rainwater. In this case, a water level sensor (not shown in FIG. 3) or the like may be provided in the rainwater tank 53, and the manager may replenish the tank with water when the water level in the rainwater tank 53 falls below a predetermined height.

[0042] Furthermore, if the system is connected to a water supply, the water may be directly poured into the raw water tank 22 or the rainwater tank 53 may be supplemented with water.

[0043] Furthermore, since the rainwater tank 53 stores rainwater, the rainwater tank 53 may be placed at a higher position than the raw water tank 22 (for example, on the roof or upper part of the side wall of the building of the purification treatment unit 20) so that the stored rainwater can be introduced into the raw water tank 22 under gravity flow. In this case, the ninth pump 40 shown in FIG. 3 does not need to be installed.

[0044] In this way, the purification treatment system of this embodiment is equipped with a conductivity sensor 52 that measures the conductivity of the water to be treated 13 in the raw water tank 22, and is equipped with a water adding means (specifically including a rainwater tank 53, a fifth motor valve 54, a control unit, etc.) that adds water when the conductivity of the water to be treated 13 measured by the conductivity sensor 52 is equal to or higher than a predetermined value. This prevents soluble substances from becoming saturated, precipitating, and crystallizing, which would clog the filtration membrane 31, and makes it easier to maintain the filtration membrane 31.

[0045] Furthermore, by configuring the purification treatment system 1 to include a rainwater tank 53 for storing rainwater as a water adding means, rainwater can be secured and used as water for diluting soluble substances even if the purification treatment system 1 is installed in a place where there is no running water facility.

[0046] (Third embodiment of the present invention) The purification treatment system according to this embodiment will be described with reference to Figures 4 and 5. The purification treatment system according to this embodiment is the purification treatment system according to the first or second embodiment, and further includes an external tank 30 that extracts and stores solids (suspended matter) and the water to be treated 13 in the raw water tank 22. Note that descriptions of this embodiment that overlap with the above-mentioned embodiments will be omitted.

[0047] Fig. 4 is a system outline diagram of the purification treatment system according to this embodiment, and Fig. 5 is a diagram showing the configuration of the raw water tank and external tank in the purification treatment system according to this embodiment. What differs from Fig. 1 in the first embodiment in that Fig. 4 includes an external tank 30 connected to the purification treatment unit 20 (raw water tank 22 in the purification treatment unit 20). The external tank 30 functions as a reserve tank, and functions as a storage tank for temporarily evacuating the water to be treated 13 or for disposing of the water directly at a specified treatment facility.

[0048] In order to purify the water 13 containing liquid and solid waste and circulate it as reusable flush water, a certain amount of time is required for anaerobic treatment. However, if the toilet rooms 10a and 10b are used frequently and the purification treatment cannot keep up, the water level in the raw water tank 22 will rise and eventually become unacceptable. In this case, the toilet rooms 10a and 10b must be stopped from being used until the purification treatment progresses to a certain extent, or the flush water must be operated with suspended matter mixed in, which is inconvenient to use. Therefore, in this embodiment, when the water level in the raw water tank 22 reaches a predetermined value or higher, the water 13 and solids contained in the water 13 are evacuated to a separately prepared external tank 30 so that the purification treatment system 1 can continue to operate.

[0049] 5, the raw water tank 22 is connected to an external tank 30 for extracting and storing the water to be treated 13 stored in the raw water tank 22 and solid matter accumulated below the raw water tank 22. A second water level sensor 55 is disposed in the raw water tank 22, and when the water level of the water to be treated 13 reaches or exceeds a predetermined height, the fifth pump 36 pumps up the water to be treated 13 with a sixth motor valve 56 open. At this time, the solid matter accumulated below the raw water tank 22 may also be pumped up, as will be described in detail later.

[0050] A float switch 58 is provided in the external tank 30, and the water level of the water 13 and solid matter stored in the external tank 30 is measured. When the water level in the external tank 30 reaches a predetermined level or higher, it is necessary to treat the water 13 and solid matter in the external tank 30. The water 13 and solid matter stored in the external tank 30 at this time may be transported to a predetermined treatment facility for disposal. On the other hand, when the water level in the external tank 30 is relatively high (below a predetermined water level) and the water level in the raw water tank 22 has also dropped below a predetermined level, the water 13 and solid matter stored in the external tank 30 may be returned to the raw water tank 22 by the sixth pump 37, and decomposition of organic matter and solid-liquid separation may be performed in the raw water tank 22. Note that a plurality of float switches 58 may be provided to issue an alarm or the like according to the water level level (for example, 50%, 80%, 100%).

[0051] In this way, in the purification treatment system of this embodiment, the water to be treated 13 and solids contained in the water to be treated 13 are evacuated to the external tank 30 before the water level in the raw water tank 22 exceeds the allowable amount (before overflow), thereby avoiding a situation in which the toilet rooms 10a, 10b become unusable and allowing the purification treatment system 1 to continue operating.

[0052] (Fourth embodiment of the present invention) The purification system according to this embodiment will be described with reference to Fig. 6. The purification system according to this embodiment has a structure that makes it easier to maintain an anaerobic state in the raw water tank 22 and minimizes clogging of the filtration membrane 31. Note that in this embodiment, descriptions that overlap with the above-mentioned embodiments will be omitted. Also, the purification system according to this embodiment is premised on the purification system according to any one of the first to third embodiments.

[0053] Fig. 6 is a diagram showing the structure of the raw water tank in the purification treatment system according to this embodiment. In Fig. 6, the raw water tank 22 is divided into at least an input area 80a where an input port 81 for inputting the water to be treated 13 sent from the crushing pump 21 is provided, and a treatment area 80b where solid-liquid separation is performed by a filtration membrane 31.

[0054] A partition 82 is provided at the boundary between the input area 80a and the treatment area 80b. This partition 82 is made of a vibration-absorbing material that easily absorbs vibrations in order to minimize the flow of the water 13 to be treated in the raw water tank 22 caused by the water 13 being input from the input port 81 and to buffer the water flow occurring between the input area 80a and the treatment area 80b.

[0055] An opening 83 is formed in the lower part of the partition 82, and the water 13 to be treated in the input area 80a and the water 13 to be treated in the treatment area 80b flow through the opening 83. If the height of the opening 83 is D, a blanket layer 84 made of solids containing at least pulp fibers (cellulose, etc.) that are the raw material for toilet paper is formed up to a position higher than D. This blanket layer 84 is formed of a first layer 84a containing a large amount of pulp fibers, which are sludge derived from toilet paper, and a second layer 84b containing a large amount of solids derived from human waste. The blanket layer 84 is formed by settling out solids contained in the water 13 to be treated input into the raw water tank 22 and sludge in the middle of decomposition, and the like, and can function as a filter layer by containing a particularly large amount of pulp fibers.

[0056] As shown in Fig. 6, the water to be treated 13 must pass through the blanket layer 84 from when it is input from the fracturing pump 21 into the raw water tank 22 until it is sent to the advanced treatment tank 23 as cleaning water through the filtration membrane 31. Therefore, fine solid matter and organic matter contained in the water to be treated 13 before decomposition are filtered by the blanket layer 84 and are less likely to reach the filtration membrane 31, making it possible to minimize clogging of the filtration membrane 31. In addition, by allowing the organic matter decomposed by the anaerobic treatment to remain in the blanket layer 84, a sufficient amount of time for the anaerobic treatment can be ensured, and the generated cleaning water can be made hygienic and highly safe.

[0057] As described above, in the purification treatment system of this embodiment, the raw water tank 22 is divided into at least an input area 80a into which the water to be treated 13 is input, and a treatment area 80b in which solid-liquid separation is performed using a filtration membrane 31, and a partition 82 capable of absorbing the water flow generated when the water to be treated 13 is input is provided at the boundary between each area, and an opening 83 is provided in the lower area of ​​the partition 82 that connects the input area 80a and the treatment area 80b. Therefore, even when the water to be treated 13 is input into the raw water tank 22, the flow of the water to be treated 13 undergoing anaerobically treatment in the raw water tank 12 can be minimized, and the anaerobic condition can be properly maintained.

[0058] In addition, since the flow of the water to be treated 13 is suppressed, it is possible to prevent solid matter and the like that has accumulated in the lower portion of the raw water tank 22 from floating up and clogging the filtration membrane 31 .

[0059] Furthermore, a blanket layer 84 made of solids including at least pulp fibers contained in the treated water 13 as dirt is formed in the communication area where the input area 80a and the treatment area 80b are connected by the opening 83, so that this blanket layer 84 can act as a filter between the input area 80a and the treatment area 80b, thereby minimizing the amount of solids floating in the treatment area 80b and preventing clogging of the filtration membrane 31.

[0060] (Fifth embodiment of the present invention) The purification treatment system according to this embodiment will be described with reference to Figures 7 and 8. The purification treatment system according to this embodiment discharges the water to be treated 13 containing the blanket layer 84 into the external tank 30 when the blanket layer 84 grows to a predetermined height or more. Descriptions of this embodiment that overlap with the previous embodiments will be omitted. The purification treatment system according to this embodiment is also based on the purification treatment system according to the fourth embodiment.

[0061] When the frequency or number of uses of the toilet rooms 10a, 10b increases, the amount of organic matter and solid matter to be treated increases, and the anaerobic treatment cannot keep up, so that waste gradually accumulates in the blanket layer 84. In this case, the blanket layer 84 is formed such that solid matter is more likely to accumulate closer to the input port 81 of the input area 80a, and the farther from the input port 81, the more the toilet paper and the like gradually melts, causing the tangled fibers of the pulp fibers to become loose. In other words, the blanket layer 84 is formed higher (thicker) closer to the input port 81 of the input area 80a, and lower (thinner) farther from the input port 81.

[0062] Therefore, in the purification treatment system 1 according to this embodiment, a discharge hole for connecting the blanket layer 84 to the external tank 30 is formed on the exterior of the raw water tank 22 corresponding to the area where the blanket layer 84 is formed, and when the blanket layer 84 reaches a predetermined height or more, the water to be treated 13 including the solids forming the blanket layer 84 is discharged from the discharge hole. At this time, a plurality of discharge holes are provided, and the amount of the water to be treated 13 and the solids discharged decreases from the input area 80a side to the treatment area 80b side.

[0063] FIG. 7 is a first diagram showing the structure of the raw water tank in the purification treatment system according to this embodiment. In FIG. 7, as described above, the height of the blanket layer 84 is formed so as to gradually decrease from the input area 80a side to the treatment area 80b side. A plurality of discharge holes 85 are formed in the exterior of the raw water tank 22 in the area where the blanket layer 84 is formed (at or near the bottom of the raw water tank 22), and the diameter of the discharge holes 85 decreases from the input area 80a side to the treatment area 80b side. In addition, a seventh pump 38 is installed between the raw water tank 22 and the external tank 30 in a drain pipe 86 connected to each discharge hole 85, and the solids forming the blanket layer 84 and the water to be treated 13 are discharged from the discharge hole 85 and sent to the external tank 30 by driving the seventh pump 38.

[0064] 7, by driving the seventh pump 38, more solids and the water to be treated 13 are discharged to the external tank 30 from the discharge holes 85 on the input region 80a side, and the amount gradually decreases toward the treatment region 80b side. In other words, after the discharge treatment by the seventh pump 38, the blanket layer 84 is made as uniform in height as possible, and the filtering function is maintained, while preventing solids and other contaminants from accumulating more than necessary near the input port 81.

[0065] 7, a transparent window 87 may be provided on the exterior of the raw water tank 22 in order to detect the height of the blanket layer 84, and an image of the inside of the raw water tank 22 may be captured from the outside of the window 87 by an imaging means such as a camera 88. The control unit may process the captured image to determine whether the height of the blanket layer 84 is equal to or greater than a predetermined height, and if it is equal to or greater than the predetermined height, the seventh pump 38 may be driven to discharge the solids forming the blanket layer 84 and the water to be treated 13 into the external tank 30.

[0066] Further, each discharge hole 85 may be provided with a mechanism (such as a sliding shutter) that can change the size of the opening of the discharge hole 85. In this way, it becomes possible to adjust the discharge amount of solid matter and the water to be treated 13 for each discharge hole 85.

[0067] FIG. 8 is a second diagram showing the structure of the raw water tank in the purification treatment system according to this embodiment. The difference between the configuration in FIG. 8 and that in FIG. 7 is that the diameters of the discharge holes 85 are all the same, but the eighth pumps 39 corresponding to the discharge holes 85 are installed in the discharge holes 85, respectively, and the suction power is set to be greater for the eighth pumps 39 corresponding to the discharge holes 85 on the input region 80a side, and smaller for the discharge holes 85 on the treatment region 80b side. In other words, the more solids and the water to be treated 13 are discharged to the external tank 30 for the discharge holes 85 on the input region 80a side, the smaller the amount of the solids and the water to be treated 13 is discharged to the external tank 30 for the discharge holes 85 on the treatment region 80b side. As a result, after the discharge treatment by the eighth pump 39, the blanket layer 84 can be made as uniform in height as possible to maintain the filter function, and the solids and other filth can be prevented from being accumulated more than necessary near the input port 81.

[0068] 8, similarly to the case of Fig. 7, a transparent window 87 may be provided on the exterior of the raw water tank 22 in order to detect the height of the blanket layer 84, and an image of the inside of the raw water tank 22 may be captured from the outside of this window 87 by an imaging means such as a camera 88. The control unit may process the captured image to determine whether the height of the blanket layer 84 is equal to or greater than a predetermined height, and if it is equal to or greater than the predetermined height, the eighth pump 39 may be driven to discharge the solids forming the blanket layer 84 and the water to be treated 13 into the external tank 30.

[0069] In the case of FIG. 8 , windows 87 may be provided on a plurality of side wall surfaces, and the height of the blanket layer 84 may be detected by a plurality of cameras 88 through these windows 87. The control unit may then adjust the suction force of each of the eighth pumps 39 in accordance with the height of the blanket layer 84 based on the images captured by each camera 88.

[0070] In this way, in the purification treatment system of this embodiment, a discharge hole 85 is formed in the exterior of the area in which the blanket layer 84 is formed, which passes through the blanket layer 84 and the external tank 30, and a discharge treatment unit (seventh pump 38, eighth pump 39, control unit, etc.) is provided that discharges the treated water 13 containing solids that form the blanket layer 84 from the discharge hole 85 when the blanket layer 84 reaches a predetermined height or above. Therefore, even if the number of times or frequency of use of the toilet rooms 10a, 10b increases, the blanket layer 84 can be prevented from accumulating more than necessary.

[0071] In addition, multiple discharge holes 85 are formed through the blanket layer 84 and the external tank 30, and the amount of treated water 13 discharged from the discharge holes 85 decreases as one moves from the input area 80a side to the treatment area 80b side. As a result, more solids and treated water 13 are discharged to the external tank 30 toward the input area 80a side, where sludge and the like are more likely to accumulate, and the amount decreases toward the treatment area 80b side. This makes it possible to prevent unnecessary accumulation of solids such as sludge, particularly on the input area 80a side, while keeping the height of the blanket layer 84 as uniform as possible.

[0072] Furthermore, a transparent window 87 capable of capturing an image of the height of blanket layer 84 is formed on the exterior of raw water tank 22 corresponding to a position that includes at least a predetermined height that is the standard for discharging blanket layer 84, and the height of blanket layer 84 is captured by camera 88 from the outside through window 87, and it is determined based on the captured image whether the height is above the predetermined height that is the standard for whether or not to discharge blanket layer 84, so that the height of blanket layer 84 can be monitored and controlled to be kept appropriate. [Explanation of symbols]

[0073] 1 Purification treatment system 10(10a, 10b) Toilet room 11 (11a, 11b) Toilet 12(12a,12b) Cleaning tank 13 Untreated water 20 Purification Processing Section 21 Fracturing Pump 22 Raw Water Tank 23 Advanced treatment tank 24 Cleaning tank 25 Activated carbon filter 26 Pressure Tank 27 Chemical tank 28 Water activator 30 External Tank 31(31a,31b) Filtration membrane 32 First Pump 33 Second Pump 34 3rd Pump 35 4th Pump 36 5th Pump 37 No. 6 Pump 38 7th Pump 39 No. 8 Pump 40 9th Pump 41 (41a, 41b) First motor valve 42 (42a, 42b) Second motor valve 43 First pressure sensor 44 No. 1 Water Level Sensor 45 3rd motor valve 46 Second pressure sensor 47 First flow sensor 48(48a,48b) 4th motor valve 49 First check valve 50 Second check valve 51 Ozone Addition Section 52 Conductivity Sensor 53 Rainwater tank 54 5th motor valve 55 Second water level sensor 56 6th motor valve 58 Float switch 80a input area 80b Processing area 81 Inlet 82 Partition 83 Opening 84 Blanket Layer 84a 1st layer 84b 2nd layer 85 Discharge hole 86 Drain pipe 87 Window 88 Camera

Claims

1. In a purification treatment system, wastewater containing sewage is purified and circulated as cleaning water, A raw water tank into which the water to be treated containing liquid waste and / or pulverized solid waste is introduced; a washing water tank disposed downstream of the raw water tank and configured to store the raw water treated in the raw water tank as washing water for washing new sewage; A purification treatment system characterized in that the raw water tank contains water to be treated that is maintained in an acidic and anaerobic state, and the water to be treated is subjected to solid-liquid separation using a filtration membrane disposed in the raw water tank.

2. The purification treatment system according to claim 1, a flush toilet disposed upstream of the raw water tank for users to relieve themselves; A purification treatment system characterized in that, when the flush toilet is flushed after the user has used the toilet, a specified chemical is mixed into the flush water to make the water to be treated acidic.

3. The purification treatment system according to claim 2, A purification treatment system, wherein the chemical is citric acid.

4. The purification treatment system according to claim 1 or 2, A purification treatment system characterized in that the pH of the water to be treated is maintained at 2.0 to 4.

8.

5. The purification treatment system according to claim 1 or 2, A sensor for measuring the conductivity of the water to be treated in the raw water tank is provided, A purification treatment system comprising a water adding means for adding water when the conductivity of the water to be treated is equal to or higher than a predetermined value as a result of measurement by the sensor.

6. The purification treatment system according to claim 5, Equipped with a rainwater tank to store rainwater, A purification treatment system, wherein the water adding means adds the stored rainwater.

7. A purification method for purifying wastewater containing sewage and circulating the purified water as cleaning water, comprising the steps of: A purification treatment method comprising maintaining the water to be treated, which contains liquid waste and / or pulverized solid waste, in an acidic and anaerobic state, and subjecting the water to solid-liquid separation using a filtration membrane.

Images