Biological treatment apparatus, biological treatment system, and biological treatment method

Abstract

To provide a gas-liquid treatment system capable of accurately predicting generation of bubbles on a liquid surface side of a container in which liquids and gases are mixed.SOLUTION: A system includes a container for mixing liquid and gas and predicts generation of bubbles at the liquid surface side according to changes in the internal pressure in a container. The internal pressure is converted into the liquid level, and the system detects the liquid level and predicts the state of bubble generation on the liquid surface side and the spouting of bubbles according to the liquid level, thereby controlling for suppression of bubbles from actual spouting.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a biological treatment system and a biological treatment method. [Background technology]

[0002] The following Patent Document 1 proposes a sludge floating prediction device that distinguishes between sludge and air bubbles in liquid and predicts the floating property of sludge. This sludge floating prediction device is provided with an imaging means for photographing the suspension inside the anaerobic reaction tank, an image processing means for identifying granular sludge based on a shape pattern from the image information obtained from the imaging means, and a determination unit for determining the floating property of sludge based on shape information and number information of the granular sludge. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3700204 Summary of the Invention [Problem to be solved by the invention]

[0004] In the sludge floating prediction device described in Patent Document 1, granular sludge is identified based on the shape pattern from the image information obtained from the imaging means by the image processing means, and the floating property of the sludge is judged by the judgment unit based on the shape information and number information of the granular sludge. Therefore, depending on the image information obtained from the imaging means, there may be an error in identifying sludge and air bubbles in the liquid, and the floating property of the sludge may not be judged accurately. Also, the method using image analysis may not be able to prevent the wastewater from boiling over due to sudden foaming in advance.

[0005] Furthermore, in biological treatment systems that treat wastewater while aerating it, if a large number of bubbles form on the surface of the wastewater, the bubbles will be expelled from the treatment vessel, making it difficult to eliminate them. Not only will this pollute the area around the biological treatment system with bubbles containing wastewater, but it may also prevent efficient treatment of the wastewater within the treatment vessel, so it is necessary to predict the formation of bubbles early.

[0006] In addition, in small-scale recycling water reclamation systems, the water quality varies greatly depending on the wastewater source, and wastewater from baths, washrooms, and laundry is also affected by surfactants, etc., and is in an environment where foaming is likely to occur due to aeration during biological treatment. For example, if a water reclamation system is assumed to be installed close to the residences of users who use the treated water, it is necessary to control the foaming so that the living environment is not deteriorated due to wastewater overflowing.

[0007] The present disclosure has been made in consideration of the above problems, and aims to provide a biological treatment device, a biological treatment system, and a biological treatment method that can accurately predict the generation of bubbles on the liquid surface side of a target liquid when the target liquid of biological treatment is purified. Furthermore, the present disclosure aims to provide a biological treatment device, a biological treatment system, and a biological treatment method that are particularly useful in small-scale water treatment systems installed indoors or in places adjacent to residences, but the present disclosure is also useful in general for foaming phenomena in containers where liquid and gas are mixed. Note that the container does not need to be completely sealed, and the present disclosure can also be applied to predicting foaming phenomena in containers that have an exhaust mechanism such as a duct. [Means for solving the problem]

[0008] The gas-liquid treatment device according to the first aspect of the present disclosure includes a container for mixing liquid and gas, and predicts the generation of bubbles on the liquid surface side based on a change in the internal pressure in the container.

[0009] In the above-mentioned gas-liquid treatment device, the internal pressure in the container may be converted into a liquid level, and the device may have a foam generation prediction unit that detects the liquid level and predicts the foam generation state on the liquid surface side according to the liquid level.

[0010] The biological treatment device described in the second aspect of the present disclosure comprises a treatment vessel that contains a target liquid for biological treatment mixed with microorganisms and purifies the target liquid using the microorganisms, a liquid level detection unit that detects the internal pressure inside the treatment vessel and the liquid level of the target liquid contained therein, and a foam generation prediction unit that predicts the foam generation state on the liquid surface side of the target liquid in accordance with the liquid level of the target liquid detected by the liquid level detection unit.

[0011] In the above biological treatment device, the foam generation prediction unit may predict a foam generation state on the liquid surface side of the target liquid in accordance with a change in the liquid level of the target liquid every predetermined time.

[0012] The above biological treatment device may further include a foam suppression unit that performs processing to suppress the generation of foam depending on the result of the prediction of the foam generation state by the foam generation prediction unit.

[0013] In the above biological treatment device, the liquid level detection unit may be a pressure sensor that detects the liquid level of the target liquid based on a change in internal pressure inside the treatment container.

[0014] The biological treatment system according to the third aspect of the present disclosure includes a biological treatment device.

[0015] The biological treatment system described in a fourth aspect of the present disclosure comprises a biological treatment device and a storage container upstream in the supply direction of the treatment container for storing the target liquid before the microorganisms are mixed in, and the defoaming treatment device comprises a transfer treatment device that returns the liquid containing the bubbles on the liquid surface side of the target liquid contained inside the treatment container to the storage container.

[0016] The biological treatment method described in the fifth aspect of the present disclosure detects the internal pressure inside a treatment vessel that contains a target liquid for biological treatment containing microorganisms and purifies the target liquid using the microorganisms, and the liquid level of the target liquid inside, and predicts the state of bubble generation on the liquid surface side of the target liquid based on the detection results of the liquid level of the target liquid. Effect of the Invention

[0017] According to the present disclosure, there is provided a gas-liquid treatment device capable of predicting the generation of bubbles on the liquid surface side due to a change in the internal pressure in a container in which liquid and gas are mixed. Also, according to the present disclosure, there is provided a biological treatment device, a biological treatment system, and a biological treatment method capable of accurately predicting the generation of bubbles on the liquid surface side of a target liquid when the target liquid of biological treatment is purified. Furthermore, according to the present disclosure, there is provided a biological treatment device, a biological treatment system, and a biological treatment method that are useful particularly in small-scale water treatment systems installed indoors or in places adjacent to residences. [Brief description of the drawings]

[0018] [Figure 1] 1 is a schematic configuration diagram showing a biological treatment system including a biological treatment device according to a first embodiment. [Diagram 2] FIG. 1 is a configuration diagram showing a biological treatment device according to a first embodiment. [Diagram 3] FIG. 1 is a block diagram showing a hardware configuration of a biological treatment system including a biological treatment device according to a first embodiment. [Figure 4] This is a graph showing the relationship between the treatment time in a biological treatment system and the standard deviation of the liquid level of the target liquid per minute. [Diagram 5] 4 is a flowchart showing the flow of processing by a control unit of a biological treatment system including a biological treatment device according to the first embodiment. [Figure 6] FIG. 11 is a schematic configuration diagram showing a part of a biological treatment system including a biological treatment device according to a second embodiment. [Figure 7] FIG. 11 is a schematic configuration diagram showing a part of a biological treatment system including a biological treatment device according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, items that are less relevant to the present disclosure are omitted. Note that the direction indicated by the arrow UP shown appropriately in each drawing is the upward vertical direction.

[0020] [First embodiment] The biological treatment system according to the first embodiment will be described below.

[0021] <Overall configuration of biological treatment system> FIG. 1 is a schematic diagram showing a biological treatment system 2 equipped with a biological treatment device 10 according to the first embodiment. As shown in FIG. 1, the biological treatment system 2 includes an adjustment tank 12, a biological treatment device 10, and a treatment liquid storage tank 16. The biological treatment device 10 includes a biological treatment tank 14. The adjustment tank 12 stores a liquid L1 to be treated by the biological treatment system 2. The liquid L1 is an example of a target liquid before being mixed with microorganisms. As an example, the liquid L1 is wastewater containing sewage or the like. The liquid L1 is not particularly limited. Examples of the liquid L1 include domestic wastewater discharged from homes and small settlements such as toilets, kitchens, and bathrooms, urban wastewater, commercial facility wastewater, agricultural wastewater, and industrial wastewater.

[0022] The biological treatment system 2 includes a pipe 18 that connects the adjustment tank 12 and the biological treatment tank 14, and a pump 20 provided on the pipe 18. In the biological treatment system 2, the liquid L1 stored in the adjustment tank 12 is supplied to the biological treatment tank 14 through the pipe 18 by driving the pump 20.

[0023] The biological treatment tank 14 contains a liquid L2 to be subjected to biological treatment. The biological treatment tank 14 is an example of a container for mixing liquid and gas, and may be sealed or not. The liquid L2 to be subjected to biological treatment is a mixed liquid in which microorganisms are mixed with the liquid L1 supplied from the adjustment tank 12. The biological treatment tank 14 is an example of a treatment container. In the biological treatment tank 14, the liquid L2 to be subjected to biological treatment is purified by the microorganisms.

[0024] Inside the biological treatment tank 14, a microfiltration membrane (MF membrane) 22 is provided, but is not limited to this. As an example, the MF membrane 22 is a type of water treatment membrane that inhibits the penetration of substances that are not dissolved in water, such as microparticles between 0.1 μm and 1 μm and microorganisms. The target liquid L2 passes through the MF membrane 22, whereby microorganisms and the like are removed.

[0025] The biological treatment tank 14 includes a gas ejection section 24, a blower 26 that sends out the gas, and a duct 28 that connects the blower 26 to the ejection section 24. By driving the blower 26, the gas is supplied to the ejection section 24 through the duct 28, and the gas is ejected from the ejection section 24 into the biological treatment tank 14. As an example, the gas is air and contains oxygen. As an example, the ejection section 24 is provided at least at one or more locations inside the biological treatment tank 14. The duct 28 extending from the portion connected to the blower 26 is connected to the ejection section 24. By ejecting air from the ejection section 24, the target liquid L2 contained inside the biological treatment tank 14 is aerated. Aeration is a type of water purification process in which oxygen is fed into the target liquid L2, and is also called aeration. In the biological treatment tank 14, by feeding air into the target liquid L2, the target liquid L2 is efficiently purified by microorganisms.

[0026] The biological treatment system 2 includes a pipe 30 that connects the portion of the biological treatment tank 14 that has permeated the MF membrane 22 to the treated liquid storage tank 16, and a pump 32 that is provided on the pipe 30. In the biological treatment system 2, the pump 32 is driven to supply the target liquid L2 that has permeated the MF membrane 22 in the biological treatment tank 14 to the treated liquid storage tank 16 through the pipe 30. The treated liquid storage tank 16 stores the treated liquid L3 that has been treated by the biological treatment system 2 (i.e., the treated liquid after the target liquid L2 has been treated by the biological treatment tank 14).

[0027] The biological treatment system 2 also includes a control unit 50 that controls each unit of the biological treatment system 2. For example, the control unit 50 individually controls the operation of the pump 20, the pump 32, the blower 26, and the like.

[0028] The biological treatment system 2 of the present disclosure may or may not be an independent object. When the biological treatment system is an independent object, it may be in a state in which it can be moved, replaced, or combined. For example, it can be transported to a specified location for use during camping, disaster evacuation, etc., and may be in a state in which multiple biological treatment systems are connected and used when it is desired to improve the treatment capacity. In addition, the biological treatment system of the present disclosure may be a module that constitutes a water treatment system (a standardized structural unit that facilitates the rearrangement of a single module or the combination of multiple modules). Examples of biological treatment systems that are not independent include those that are incorporated as part of a building or an object other than a building. Examples of objects other than a building include, but are not limited to, automobiles, trains, ships, aircraft, trailer houses, etc.

[0029] Furthermore, there are no particular limitations on the type of microorganisms mixed in the target liquid L2 of the biological treatment tank 14. For example, the microorganisms may be either aerobic bacteria or anaerobic bacteria, or a combination of these. The biological treatment tank 14 may be a tank that combines an aerobic area and an anaerobic area, or may be a multiple tank with separate aerobic and anaerobic tanks.

[0030] Moreover, the blower 26 may supply air to the subject liquid L2 continuously or intermittently.

[0031] In addition, the treated liquid L3 stored in the treated liquid storage tank 16 may be applied to a small-scale circulating water reclamation system in which the treated liquid L3 is made available to users again as purified water and circulated to the adjustment tank 12 as wastewater and reprocessed as liquid L1.

[0032] <Biological treatment equipment> Fig. 2 is an enlarged configuration diagram of the biological treatment device 10 used in the biological treatment system 2. As shown in Fig. 2, the biological treatment device 10 includes a pressure sensor 40 and a defoaming treatment unit 42 in addition to the above-mentioned biological treatment tank 14, the jetting unit 24, and the MF membrane 22.

[0033] The pressure sensor 40 is an example of a liquid level detection unit, and detects the internal pressure inside the biological treatment tank 14 and the liquid level of the target liquid L2 contained therein. The liquid level of the target liquid L2 refers to the height of the liquid surface of the target liquid L2 from a reference position inside the biological treatment tank 14. The reference position is, for example, the bottom surface of the biological treatment tank 14.

[0034] As an example, the pressure sensor 40 detects the liquid level of the target liquid L2 based on a change in the internal pressure inside the biological treatment tank 14. More specifically, when the gas phase becomes pressurized due to bubbles, pressure is applied to the liquid phase, and the pressure sensor 40 detects the pressurized state. When there is no foaming at the liquid surface, the water pressure is due to atmospheric pressure, but when the internal pressure inside the biological treatment tank 14 increases due to foaming, the liquid phase receives a pressure equal to or greater than atmospheric pressure, and the pressure sensor 40 can detect a slight change in pressure (see FIG. 4). For example, the pressure sensor 40 detects the change in internal pressure due to the liquid level of the target liquid L2 using a diaphragm, and converts it into a storage level of the target liquid L2. When bubbles are generated on the liquid surface side of the target liquid L2, the pressure sensor 40 can detect the liquid level of the target liquid L2 containing bubbles.

[0035] The configuration of the present disclosure is not limited to the pressure sensor 40, and may be other liquid level sensors or water level sensors, or may be other types of contact water level gauges or non-contact water level gauges. For example, the water level fluctuations of a laser type or ultrasonic water level gauge as a contact water level gauge can be similarly applied. Furthermore, a float type, a capacitance type level gauge, or a differential pressure type level gauge may be used as a contact water level gauge. Furthermore, a radio wave type water level gauge or an ultrasonic water level gauge may be used as a non-contact water level gauge.

[0036] In a small-scale circulating biological treatment system, it is not preferable to use chemicals unnecessarily, and it is preferable to carry out foam suppression treatments to suppress the generation of foam as follows. (1) to (7) are examples of foam suppression treatments, and they can also be called defoaming treatments because they involve the destruction of foam. (1) Stop aeration in the biological treatment tank 14. (2) Add a defoamer or antifoaming agent such as ethanol. (3) The treated water is sprayed into the biological treatment tank 14. (4) Decompose the foam-generating substances using ozone, UV (ultraviolet rays), etc. (5) The bubbles containing the target liquid L2 are released through a duct to the adjustment tank 12. (6) Lower the liquid level in the biological treatment tank 14 (if the target liquid is water, the water level). (7) When the liquid L1 is transferred to the biological treatment tank 14, oxygen or ozone gas is mixed therein and UV irradiation is also used to suppress foaming in the biological treatment tank 14. For example, a process for suppressing foam generation may be appropriately selected and executed based on the change in the standard deviation of the liquid level of the target liquid L2, such as combining A and B above to eliminate foam, adding C as a safety device in addition to A and B, or implementing D as an emergency measure.

[0037] The defoaming treatment unit 42 is an example of a foam suppression unit, and has a function of performing a process for suppressing the generation of bubbles on the liquid surface side of the target liquid L2. In the first embodiment, the defoaming treatment unit 42 includes a storage unit 43 in which an antifoaming agent 46 is stored, a supply pipe 44 extending downward from a lower portion of the storage unit 43, and a valve 45 provided on the supply pipe 44. The valve 45 is, for example, a solenoid valve, and the opening and closing of the valve 45 is controlled by the control unit 50. When the valve 45 is opened, the antifoaming agent 46 stored in the storage unit 43 is added to the target liquid L2 through the supply pipe 44. The defoaming treatment unit 42 is an example of an addition treatment unit.

[0038] The defoaming agent 46 has a function of defoaming the bubbles in the target liquid L2 or suppressing the generation of bubbles. As the defoaming agent 46, for example, an oil type in which a defoaming component is dispersed in oil or the like, an activator type such as a surfactant, or an emulsion type in which a defoaming component (higher alcohol, ester, etc.) is emulsified and dispersed in water may be used. Examples of the activator type include agents that have a foam breaking effect, such as silicone-based surfactants such as dimethylpolysiloxane and ethanol, as well as returning treated water and spraying it (preferable in a circulating water treatment system).

[0039] Although not shown, the biological treatment tank 14 may be provided with an addition device for adding a nutrient source for the microorganisms to the target liquid L2. The nutrient source is not particularly limited as long as it is an organic matter that can be decomposed by the microorganisms. From the viewpoint of immediate effect, alcohols such as ethanol, and organic matter with a small molecular weight such as sugars are preferable.

[0040] Although not shown, the biological treatment tank 14 may be provided with a temperature sensor that measures the temperature of the target liquid L2 and an agitator that agitates the target liquid L2.

[0041] <Control Unit> Fig. 3 is a block diagram showing the hardware configuration of the biological treatment system 2. As shown in Fig. 3, the control unit 50 has components including a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, a RAM (Random Access Memory) 53, a storage 54, and an input / output interface 55. Each component is connected to each other via a bus 59 so as to be able to communicate with each other.

[0042] The CPU 51 is a central processing unit that executes various programs and controls each part. The CPU 51 is an example of a processor. That is, the CPU 51 reads a program from the ROM 52 or the storage 54, and executes the program using the RAM 53 as a working area. The CPU 51 performs control processing of each of the above components according to the program recorded in the ROM 52 or the storage 54. In the first embodiment, the ROM 52 or the storage 54 stores a program that controls each of the above components.

[0043] The ROM 52 stores various programs and various data. The RAM 53 temporarily stores programs or data as a working area. The storage 54 is configured with an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs including an operating system and various data.

[0044] The input / output interface 55 is an interface for communicating with each of the above components (each device mounted in the biological treatment system 2). The control unit 50 is connected to the pressure sensor 40, the valve 45 of the defoaming treatment unit 42, the pumps (pump 20 and pump 32 shown in FIG. 1), and the blower 26 via the input / output interface 55. The pressure sensor 40, the valve 45 of the defoaming treatment unit 42, the pumps, and the blower 26 may be directly connected via a bus 59.

[0045] In the control unit 50, a CPU 51 controls the operations of the valve 45 of the defoaming treatment unit 42, the pumps (the pump 20 and the pump 32 shown in FIG. 1), and the blower .

[0046] In addition, the CPU 51 receives detection information (detection data) on the liquid level of the target liquid L2 detected by the pressure sensor 40 via the input / output interface 55.

[0047] The CPU 51 predicts a bubble generation state on the liquid surface side of the target liquid L2 according to detection information (detection data) of the liquid level of the target liquid L2 detected by the pressure sensor 40. The control unit 50 is an example of a bubble generation prediction unit. In the first embodiment, the CPU 51 functions as the bubble generation prediction unit.

[0048] As an example, the CPU 51 calculates the standard deviation of the liquid level for each predetermined time from the detection information (detection data) of the liquid level of the target liquid L2 detected by the pressure sensor 40, and predicts the state of bubble generation on the liquid surface side of the target liquid L2 according to the standard deviation. The standard deviation of the liquid level of the target liquid L2 for each predetermined time is an example of the change in the liquid level of the target liquid for each predetermined time. Here, the standard deviation is one of the statistical indices, and is an index indicating how far the data deviates from the average value (i.e., how much it varies). The larger the value of the standard deviation, the larger the variation. In the first embodiment, the state of bubble generation on the liquid surface side of the target liquid L2 corresponding to the fluctuation range (variation in fluctuation) of the liquid level of the target liquid L2 is predicted from the standard deviation of the liquid level of the target liquid L2 for each predetermined time.

[0049] Fig. 4 is a graph showing the relationship between the treatment time by the biological treatment system 2 and the standard deviation of the liquid level for each predetermined time (every minute in Fig. 4) calculated from the liquid level detection information of the target liquid L2 by the pressure sensor 40. As shown in Fig. 4, the standard deviation value indicates whether the liquid surface side of the target liquid L2 inside the biological treatment tank 14 is in a stable normal state, or in a foaming state where bubbles have occurred on the liquid surface side of the target liquid L2. In Fig. 4, the standard deviation is calculated from the average liquid level for each minute.

[0050] As an example, the CPU 51 monitors the standard deviation of the liquid level of the target liquid L2 every predetermined time (e.g., every minute). It is preferable to monitor the liquid level of the target liquid L2 in mm units in order to predict foaming. The CPU 51 detects a foaming state when the liquid level varies greatly every predetermined time (e.g., every minute) and fluctuates irregularly. Specifically, the CPU 51 monitors the standard deviation of the liquid level of the target liquid L2 and starts controlling the aeration amount at the timing when foaming is predicted.

[0051] As an example, the CPU 51 operates the defoaming treatment unit 42 (see FIG. 2) according to the prediction result of the foam generation state, and performs a process to suppress the generation of foam. In the first embodiment, the CPU 51 opens the valve 45 of the defoaming treatment unit 42 and sprays the defoaming agent 46 in the storage unit 43 to the target liquid L2 in the biological treatment tank 14. At this time, the aeration by the blower 26 may be stopped once. Then, while defoaming by spraying the defoaming agent 46, aeration may be resumed and the standard deviation of the liquid level of the target liquid L2 may be observed to determine whether or not to resume biological treatment. This makes it possible to defoam the bubbles on the liquid surface side of the target liquid L2 in the biological treatment tank 14, or to suppress the generation of bubbles. This makes it possible to effectively prevent the overflow of foam from the biological treatment tank 14 (foam containing sludge spouting out of the biological treatment tank 14 beyond the limit water level of the biological treatment tank 14). In addition, by performing the defoaming process at the early stage of foaming, the amount of the defoaming agent 46 used can be reduced.

[0052] As an example, the CPU 51 can accurately predict foaming by calculating the standard deviation of the liquid level of the target liquid L2 under normal conditions and performing zero point calibration. As another example, the CPU 51 may execute defoaming processing by the defoaming processing unit 42 when the standard deviation of the liquid level of the target liquid L2 exceeds 2, thereby preventing the target liquid L2 from boiling over due to foaming. As another example, the standard deviation may be calculated from the average liquid level every minute. Since this is a measure against sudden foaming of the target liquid L2, the standard deviation of the liquid level every minute is sufficient, and a situation in which the defoaming cannot keep up is avoided.

[0053] 4, when the standard deviation of the liquid level of the target liquid L2 exceeds 2, the blower 26 is stopped to stop aeration, and defoaming treatment is performed by the defoaming treatment unit 42. Then, after it is confirmed that the change in the standard deviation of the liquid level of the target liquid L2 has stabilized, aeration by the blower 26 is resumed. 4, when a change in the liquid level of the target liquid L2 occurs, it is possible to predict the next sudden foaming due to foaming. Therefore, aeration by the blower 26 is stopped, and defoaming treatment is performed by the defoaming treatment unit 42. This results in a foam-suppressed state in which the change in the standard deviation of the level is stable. 4, when a change in the liquid level occurs, aeration by the blower 26 is stopped and defoaming treatment is performed by the defoaming treatment unit 42. Although not shown, for example, if defoaming treatment is not performed in the third state 156, once foaming occurs, it cannot be easily defoamed and foam overflow occurs, so it is important to predict foaming.

[0054] <Action and Effects> Next, the operation of the biological treatment system 2 including the biological treatment device 10 of the first embodiment will be described.

[0055] 5 is a flowchart showing the flow of processing in the biological processing system 2. The CPU 51 reads out a processing program from the ROM 52 or storage 54, loads it into the RAM 53, and executes it to process information.

[0056] In the biological treatment system 2, first, the target liquid L2 is supplied into the biological treatment tank 14.

[0057] When information processing by the biological treatment system 2 is started, the CPU 51 stops the pumps 20 and 32 (step S291). In this state, the blower 26 is driven.

[0058] The CPU 51 determines whether a predetermined time has elapsed (step S292). The predetermined time is set to, for example, 10 seconds. This allows the liquid level of the target liquid L2 inside the biological treatment tank 14 to stabilize.

[0059] If the predetermined time has not elapsed (step S292: NO), the CPU 51 waits until the predetermined time has elapsed.

[0060] If the predetermined time has elapsed (step S292: YES), the CPU 51 acquires detection information of the liquid level of the target liquid L2 by the pressure sensor 40 in the biological treatment tank 14 for the predetermined time (step S293). The predetermined time is preferably one minute or more, and is set to, for example, one minute.

[0061] The CPU 51 calculates the standard deviation from the detection information of the liquid level of the target liquid L2 (step S294). For example, the CPU 51 calculates the standard deviation from the average value of the liquid level of the target liquid L2 acquired over a predetermined time period (for example, one minute).

[0062] The CPU 51 sets the calculated standard deviation as a reference value (step S295).

[0063] The CPU 51 drives the pumps 20, 32 and the blower 26 (step S296). Alternatively, the pumps 20, 32 and the blower 26 may be driven after the process of step S293.

[0064] The CPU 51 acquires information on the liquid level of the target liquid L2 detected by the pressure sensor 40 in the biological treatment tank 14 (step S301).

[0065] The CPU 51 calculates the standard deviation of the level of the target liquid L2 for each predetermined time from the level information of the target liquid L2 (step S302). As an example, the standard deviation of the level of the target liquid L2 for each predetermined time is zero-point calibrated based on a reference value. As a result, the standard deviation of the level of the target liquid L2 for each predetermined time is the difference between the actual calculated value and the reference value.

[0066] The CPU 51 judges whether the standard deviation of the liquid level of the target liquid L2 for each predetermined time is equal to or greater than a threshold value (step S303). For example, the CPU 51 predicts the foam generation state on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 based on the standard deviation of the liquid level of the target liquid L2 for each predetermined time. For example, it is preferable to execute the defoaming process by the defoaming processor 42 before the standard deviation becomes 5, and it is preferable to execute the defoaming process immediately when the standard deviation exceeds 2 in order to prevent rapid foaming. For this reason, the threshold value is set to, for example, 2 and is stored in advance in the storage 54. If the standard deviation of the liquid level of the target liquid L2 for each predetermined time is equal to or greater than the threshold value, the CPU 51 predicts that the foam generation state on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 will soon exceed the reference amount. If the standard deviation of the liquid level of the target liquid L2 for each predetermined time is smaller than the threshold value, the CPU 51 predicts that the foam generation state on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 will be equal to or less than the reference amount.

[0067] If the standard deviation of the liquid level of the target liquid L2 for each predetermined time is equal to or greater than the threshold value (step S303: YES), the CPU 51 drives the defoaming treatment unit 42 for a set time (step S304). The CPU 51 executes a process for suppressing bubbles on the liquid surface side of the target liquid L2 by driving the defoaming treatment unit 42. At this time, aeration by the blower 26 may be stopped. As a result, the valve 45 of the defoaming treatment unit 42 is opened for a set time, and the defoaming agent 46 in the storage unit 43 or the treatment liquid L3 is sprayed onto the target liquid L2 in the biological treatment tank 14. The above defoaming process causes bubbles on the liquid surface side of the target liquid L2 in the biological treatment tank 14 to be defoamed.

[0068] When the standard deviation of the liquid level of the target liquid L2 for each predetermined time is smaller than the threshold value (step S303: NO), the CPU 51 continues the current processing state (step S305). That is, the defoaming processing unit 42 does not perform processing.

[0069] The CPU 51 determines whether or not an instruction to end the biological treatment has been given (step S306). For example, when an operation button for ending the biological treatment in the biological treatment tank 14 is operated, or when the power supply to the biological treatment system 2 is turned off, the CPU 51 determines that an instruction to end the biological treatment has been given. When an instruction to end the biological treatment has not been given (step S306: NO), the CPU 51 returns to the process of step S301.

[0070] When the end of the biological treatment is instructed (step S306: NO), the processing based on the information processing program of the biological treatment system 2 is ended.

[0071] In the biological treatment device 10, the pressure sensor 40 detects the liquid level of the target liquid L2 contained in the biological treatment tank 14. As described above, the pressure sensor 40 detects the change in the internal pressure caused by the slight generation of bubbles inside the biological treatment tank 14, and converts the internal pressure into a liquid level. Then, the CPU 51 predicts the generation state of bubbles on the liquid surface side of the target liquid L2 according to the liquid level of the target liquid L2 detected by the pressure sensor 40. Therefore, in the biological treatment device 10, when the target liquid L2 for biological treatment is purified, the generation of bubbles on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 can be predicted with high accuracy. More specifically, in the biological treatment device 10, for example, compared to a case in which the bubbles generated on the liquid surface side of the target liquid L2 are photographed by a photographing means and the generation state of bubbles on the liquid surface side of the target liquid L2 is predicted by image processing, the generation of bubbles on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 can be predicted in advance and the foaming that may occur thereafter can be predicted. As a result, in the biological treatment device 10, the blowing out of foam from the biological treatment tank 14 (i.e., foam overflow) is suppressed, the target liquid L2 inside the biological treatment tank 14 can be efficiently purified by microorganisms, and the use of antifoaming agent 46 can also be reduced.

[0072] In the above biological treatment device 10, the CPU 51 predicts the foam generation state on the liquid surface side of the target liquid L2 in response to changes in the liquid level of the target liquid L2 at predetermined time intervals. Therefore, in the biological treatment device 10, foam generation on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 can be predicted with higher accuracy than when the liquid level of the target liquid L2 is detected periodically or intermittently.

[0073] In the above-described biological treatment device 10, the pressure sensor 40 detects the liquid level of the target liquid L2 based on a change in the internal pressure inside the biological treatment tank 14. Therefore, in the biological treatment device 10, the liquid level of the target liquid L2 can be detected more accurately and in real time, compared to a case in which the liquid level of the target liquid L2 is determined by image analysis.

[0074] The above-mentioned biological treatment device 10 has a defoaming treatment unit 42 that performs a process to suppress foam generation according to the result of the prediction of the foam generation state. Therefore, the biological treatment device 10 can suppress foam from blowing out from the biological treatment tank 14 compared to the case where defoaming treatment of the target liquid L2 is not performed.

[0075] The biological treatment system 2 is also equipped with a biological treatment device 10. Therefore, in the biological treatment system 2, when the target liquid L2 of biological treatment is purified, it is possible to accurately predict the generation of bubbles on the liquid surface side of the target liquid L2 inside the biological treatment tank 14.

[0076] Furthermore, in the biological treatment method, the liquid level of the target liquid L2 in the biological treatment tank 14 that contains the biological treatment target liquid L2 mixed with microorganisms is detected, and the state of foam generation on the liquid surface side of the target liquid L2 is predicted based on the detection result of the liquid level of the target liquid L2. Therefore, in the biological treatment method, when the target liquid L2 for biological treatment is purified, it is possible to accurately predict foam generation on the liquid surface side of the target liquid L2 in the biological treatment tank 14.

[0077] Second Embodiment Next, a biological treatment system including a biological treatment device according to a second embodiment will be described. Note that the same components as those in the first embodiment described above are given the same reference numbers and the description thereof will be omitted.

[0078] Fig. 6 is a schematic diagram showing a part of a biological treatment system 100 including a biological treatment device 101 according to a second embodiment. As shown in Fig. 6, the biological treatment system 100 includes a biological treatment device 101 including an adjustment tank 12 and a biological treatment tank 14, a pipe 18 connecting the adjustment tank 12 and the biological treatment tank 14, and a pump 104 provided on the pipe 18. In the biological treatment system 100, the pump 104 is driven to supply liquid L1 stored in the adjustment tank 12 to the biological treatment tank 14. The pump 104 is an example of a supply unit.

[0079] The biological treatment system 100 includes a defoaming treatment unit 102 that performs treatment to suppress foam generation in the target liquid L2 in the biological treatment tank 14, in a pipe 18 that connects the adjustment tank 12 and the biological treatment tank 14. The defoaming treatment unit 102 is an example of a foam suppression unit. The defoaming treatment unit 102 includes a treatment unit 106 that transfers the liquid L1 to the biological treatment tank 14 while inactivating or decomposing foam-causing substances by ozone treatment and / or UV irradiation (ultraviolet light irradiation) in the middle of the pipe 18. The defoaming treatment unit 102 may also stop the supply of the liquid L1 to the biological treatment tank 14 by stopping the pump 104. The biological treatment system 100 further includes a control unit 110 that controls each unit of the biological treatment system 100. In the second embodiment, the control unit 110 controls the operation of the treatment unit 106 or the pump 104.

[0080] The control unit 110 includes a CPU 51 (see FIG. 3), and controls the operation of the pump 104 or the treatment device 106 according to the result of prediction of the foam generation state by the CPU 51. Other configurations of the biological treatment system 100 are similar to those of the biological treatment system 2 of the first embodiment.

[0081] In addition to the treatment by the defoaming treatment unit 102, the biological treatment system 100 may also perform ozone spraying into the gas phase on the foaming surface of the target liquid L2 inside the biological treatment tank 14.

[0082] The biological treatment system 100 has the following actions and effects in addition to the actions and effects of the same configuration as the biological treatment system 2 of the first embodiment.

[0083] In a biological treatment system 100 equipped with a biological treatment device 101, a defoaming treatment device 102 drives a treatment device 106 while a pump 104 is in operation, thereby supplying liquid L1 to a biological treatment tank 14 while inactivating and decomposing foam-causing substances. This reduces bubbles on the liquid surface side of the target liquid L2 inside the biological treatment tank 14, and further suppresses the generation of bubbles.

[0084] The defoaming treatment unit 102 may also stop the pump 104 from supplying the liquid L1 to the biological treatment tank 14 by the pump 104. As a result, the target liquid L2 that has permeated through the MF membrane 22 from the biological treatment tank 14 is supplied to the treatment liquid storage tank 16 (see FIG. 1), reducing the amount of the target liquid L2 inside the biological treatment tank 14 and reducing bubbles on the liquid surface side of the target liquid L2. Therefore, in the biological treatment device 101 and the biological treatment system 100, the generation of bubbles on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 can be suppressed with a simple configuration.

[0085] Third Embodiment Next, a biological treatment system including a biological treatment device according to a third embodiment will be described. Note that the same components as those in the first and second embodiments described above are given the same reference numbers and the description thereof will be omitted.

[0086] Fig. 7 is a schematic diagram showing a part of a biological treatment system 120 including a biological treatment device 121 according to a third embodiment. As shown in Fig. 7, the biological treatment system 120 includes a biological treatment device 121 including a biological treatment tank 14, and a foam suppression unit 122 that performs a process to suppress the generation of foam in the target liquid L2 inside the biological treatment tank 14. The foam suppression unit 122 is provided between the adjustment tank 12 and the biological treatment tank 14. The adjustment tank 12 is an example of a storage container arranged upstream of the biological treatment tank 14 in the supply direction.

[0087] The foam suppression unit 122 has a function of returning the liquid containing bubbles on the liquid surface side of the target liquid L2 contained inside the biological treatment tank 14 to the adjustment tank 12. The foam suppression unit 122 is an example of a transfer processing unit. Specifically, the foam suppression unit 122 has a pipe 124 connecting the adjustment tank 12 and the biological treatment tank 14. The pipe 124 is provided with a pump 126, but the pump 126 may be omitted. The connection part 124A of the pipe 124 with the biological treatment tank 14 is provided at the upper part of the biological treatment tank 14 and near the liquid surface of the target liquid L2 inside the biological treatment tank 14. The foam suppression unit 122 transfers the liquid containing bubbles on the liquid surface side of the target liquid L2 inside the biological treatment tank 14 to the adjustment tank 12 through the pipe 124. At this time, the liquid containing bubbles on the liquid surface side of the target liquid L2 may be transferred to the adjustment tank 12 by driving the pump 126.

[0088] Furthermore, the biological treatment system 120 includes a control unit 130 that controls each unit of the biological treatment system 120. The control unit 130 includes a CPU 51 (see FIG. 3), and controls the operation of the pump 126 of the foam suppression unit 122 according to the result of the prediction of the foam generation state by the CPU.

[0089] Although not shown in the drawings, a filter for filtering microorganisms may be provided at a portion inside the biological treatment tank 14 to which the piping 124 is connected. Other configurations of the biological treatment system 120 are similar to those of the biological treatment system 2 of the first embodiment.

[0090] The biological treatment system 120 has the following actions and effects in addition to the actions and effects of the configuration similar to those of the biological treatment system 2 of the first embodiment.

[0091] In the biological treatment system 120, the foam suppression unit 122 returns the foam-containing liquid on the surface side of the target liquid L2 inside the biological treatment tank 14 to the adjustment tank 12 through the piping 124. At this time, by driving the pump 126, the foam-containing liquid on the surface side of the target liquid L2 inside the biological treatment tank 14 is quickly returned to the adjustment tank 12 through the piping 124. This prevents an increase in foam on the surface side of the target liquid L2 inside the biological treatment tank 14. Therefore, in the biological treatment system 120, the generation of foam on the surface side of the target liquid L2 inside the biological treatment tank 14 can be suppressed.

[0092] In the third embodiment, the pipe 124 and the pump 126 are provided, but the present disclosure is not limited to this configuration. For example, a configuration in which the liquid containing bubbles in the target liquid L2 in the biological treatment tank 14 overflows and returns to the adjustment tank 12 may be used.

[0093] 〔others〕 In the first embodiment, the defoaming treatment unit 42 adds the defoaming agent 46 to the target liquid L2 inside the biological treatment tank 14 by opening the valve 45, but the present disclosure is not limited to this configuration. For example, the defoaming treatment unit may be configured to spray the defoaming agent into the target liquid L2 inside the biological treatment tank 14 by a supply means such as a pump.

[0094] In the third embodiment, the foam suppression unit 122 transfers the foam-containing liquid on the surface side of the target liquid L2 inside the biological treatment tank 14 to the adjustment tank 12 by the pump 126 provided in the piping 124, but the present disclosure is not limited to this configuration. For example, the defoaming treatment unit may be configured to provide a piping connected to the adjustment tank 12 from the top of the biological treatment tank 14, and to transfer the foam-containing liquid on the surface side of the target liquid L2 inside the biological treatment tank 14 to the adjustment tank 12 by opening a valve provided in the piping. Furthermore, when the connection position of the piping is at the top of the adjustment tank 12 and the biological treatment tank 14, the piping may be a simple pipe without a valve.

[0095] In the first to third embodiments, the standard deviation of the liquid level of the target liquid L2 for each predetermined time in the biological treatment tank 14 is calculated, and the foam generation state on the liquid surface side of the target liquid L2 is predicted according to the standard deviation of the liquid level, but the present disclosure is not limited to this configuration. For example, in the biological treatment tank 14, a change in the liquid level of the target liquid L2 for each predetermined time (e.g., the amount of fluctuation) may be detected, and the foam generation state on the liquid surface side of the target liquid L2 may be predicted according to the change in the liquid level (e.g., the amount of fluctuation). Alternatively, an abnormality in the change in the target liquid L2 may be detected from learning data related to the liquid level change and the standard deviation of the liquid level in past biological treatments, and the foam generation state on the liquid surface may be predicted.

[0096] In addition, although the biological treatment device and biological treatment system have been described in the first to third embodiments, the present disclosure is not limited to this configuration. For example, the present disclosure may be applied to a gas-liquid treatment device that includes a container for mixing liquid and gas and predicts the generation of bubbles on the liquid surface side due to a change in the internal pressure in the container, and a gas-liquid treatment system that includes this gas-liquid treatment device.

[0097] Although the present disclosure has been described in detail with respect to a specific embodiment, it will be apparent to those skilled in the art that the present disclosure is not limited to such an embodiment, and that various other embodiments are possible within the scope of the present disclosure.

[0098] [Preferred embodiment of the present disclosure] Preferred aspects of the present disclosure will be described below.

[0099] [Additional note 1] A container for mixing a liquid and a gas is provided, A gas-liquid treatment device that predicts the generation of bubbles on the liquid surface side based on a change in the internal pressure in the container.

[0100] [Additional note 2] 2. The gas-liquid treatment device according to claim 1, further comprising a bubble generation prediction unit that converts the internal pressure of the container into a liquid level, detects the liquid level, and predicts the state of bubble generation on the liquid surface side according to the liquid level.

[0101] [Additional note 3] A treatment vessel that contains a liquid to be subjected to biological treatment containing microorganisms and purifies the liquid to be subjected to biological treatment by the microorganisms; a liquid level detection unit that detects an internal pressure inside the processing vessel and a liquid level of the target liquid contained therein; a bubble generation prediction unit that predicts a bubble generation state on a liquid surface side of the target liquid according to the liquid level of the target liquid detected by the liquid level detection unit; A biological treatment device having the above structure.

[0102] [Additional note 4] The biological treatment device according to claim 3, wherein the foam generation prediction unit predicts a foam generation state on the liquid surface side of the target liquid in accordance with a change in the liquid level of the target liquid at every predetermined time.

[0103] [Additional note 5] 5. The biological treatment device according to claim 3 or 4, further comprising a foam suppression unit that performs processing to suppress the generation of foam depending on a result of the prediction of the foam generation state by the foam generation prediction unit.

[0104] [Additional note 6] 6. The biological treatment device according to any one of claims 3 to 5, wherein the liquid level detection unit is a pressure sensor that detects the liquid level of the target liquid based on a change in internal pressure inside the treatment container.

[0105] [Additional note 7] A biological treatment system comprising the biological treatment device according to any one of claims 3 to 6.

[0106] [Additional note 8] A biological treatment system comprising: the biological treatment apparatus according to claim 5; and a storage container for storing the target liquid before the microorganisms are mixed in, located upstream of the treatment container in the supply direction, wherein the defoaming treatment unit comprises a transfer treatment unit for returning liquid containing the bubbles on the liquid surface side of the target liquid contained inside the treatment container to the storage container.

[0107] [Additional note 9] Detecting the internal pressure of a treatment vessel that contains a liquid to be treated by biological treatment and purifies the liquid by the microorganisms, and the liquid level of the liquid to be treated; A biological treatment method which predicts the state of foam generation on the liquid surface side of the target liquid based on the detection result of the liquid level of the target liquid. [Explanation of symbols]

[0108] 2. Biological treatment system 10 Biological treatment equipment 12 Adjustment tank (storage container) 14 Biological treatment tank (treatment vessel) 40 Pressure sensor (liquid level detection part) 42 Antifoam treatment section (foam suppression section) 46 Defoamers 50 Control unit (bubble generation prediction unit) 100 Biological treatment system 101 Biological treatment equipment 102 Antifoam treatment section (foam suppression section) 104 Pump (supply section) 110 Control unit (bubble generation prediction unit) 120 Biological Treatment System 121 Biological treatment equipment 122 Foam suppression section (transportation processing section) 130 Control unit (bubble generation prediction unit) L1 Liquid (the target liquid before the microorganisms are mixed) L2 Target liquid (target liquid containing microorganisms)

Claims

1. A container for mixing a liquid and a gas is provided, A gas-liquid treatment device that predicts the generation of bubbles on the liquid surface side based on a change in the internal pressure in the container.

2. 2. The gas-liquid treatment apparatus according to claim 1, further comprising a bubble generation predicting section for detecting the internal pressure of the vessel and predicting the state of bubble generation on the liquid surface side according to the liquid level.

3. A treatment vessel that contains a liquid to be subjected to biological treatment containing microorganisms and purifies the liquid to be subjected to biological treatment by the microorganisms; a liquid level detection unit that detects an internal pressure inside the processing vessel and a liquid level of the target liquid contained therein; a bubble generation prediction unit that predicts a bubble generation state on a liquid surface side of the target liquid according to the liquid level of the target liquid detected by the liquid level detection unit; A biological treatment device having the above structure.

4. The biological treatment device according to claim 3 , wherein the foam generation prediction unit predicts a foam generation state on the liquid surface side of the target liquid in response to a change in the liquid level of the target liquid every predetermined time.

5. The biological treatment device according to claim 3 , further comprising a foam suppression unit that performs processing to suppress the generation of foam in accordance with a result of the prediction of the state of foam generation by the foam generation prediction unit.

6. The biological treatment device according to claim 3 , wherein the liquid level detection unit is a pressure sensor that detects the liquid level of the target liquid based on a change in internal pressure inside the treatment container.

7. A biological treatment system comprising the biological treatment device according to any one of claims 3 to 6.

8. The biological treatment device according to claim 5 , a storage container for storing the target liquid before the microorganisms are mixed therein, the storage container being disposed upstream of the treatment container in a supply direction; The foam suppression unit is a biological treatment system that includes a transport processing unit that returns the foam-containing liquid on the liquid surface side of the target liquid contained inside the treatment container to the storage container.

9. Detecting the internal pressure of a treatment vessel that contains a liquid to be treated by biological treatment and purifies the liquid by the microorganisms, and the liquid level of the liquid to be treated; A biological treatment method which predicts the state of foam generation on the liquid surface side of the target liquid based on the detection result of the liquid level of the target liquid.

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