JP2018178621A - Sewage discharge method and sewage purification system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further improve reliability of discharging purified treatment water securing a discharge allowable quality into a natural environment water area.SOLUTION: In taking in and purifying sewage discharged from a facility using pure water, a water quality control parameter which is used in discharge allowable quality determination is measured on the sewage purified in an annex purification facility by an index instrument, and the purified sewage is discharged into a natural environment water area when the measured water quality control parameter satisfies the water quality control parameter. When the measured water quality control parameter does not satisfy the water quality control parameter, discharge into a natural environment water area is stopped by a water channel changing valve in a downstream side of the index instrument, and the purified sewage is fed into a public sewage channel reaching a sewage purification treatment facility from the water channel changing valve or is circulated to the annex purification facility from the water channel changing valve.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sewage discharge method and a sewage purification system in a tap water using facility that discharges sewage generated using tap water.

  Equipped with purification devices not only in commerce and industry such as factories, commercial buildings, tenant buildings, bathing facilities, supermarkets, sports clubs, complex buildings, etc., but also in water and sewage facilities such as detached houses and housing complexes. Sewage discharge methods for self-purifying sewage are known (for example, Patent Document 1).

JP, 2014-12927, A

  In recent years, interest in the water quality of purified treated water actually released to natural environment water areas has also been raised not only by the local residents around the facility using the water supply but also by the owners and users of the facility using the water It is rising. For this reason, even if the purification facility capable of purifying water to the allowable discharge quality is permitted to be discharged into the natural environment water area, the reliability of discharging purified treated water in which the allowable water quality is secured to the natural environment water area To be required to raise the

  The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following modes.

  (1) According to one aspect of the present invention, there is provided a sewage discharge method for a facility using water for discharging sewage generated using the water. This sewage discharge method comprises the following steps (1) to (3). In the step (1), the sewage discharged from the facility for using fresh water is taken, and the taken-out sewage is an attached purification facility capable of purifying until the discharge allowable water quality is permitted to be discharged to the natural environment water area. Purify. In the step (2), the water quality control parameter used to determine the discharge allowable water quality of the taken-in sewage is measured for the purified sewage in the step (1) by the index measuring instrument, and the measured water quality control parameter measured Determines whether the water quality control parameter is satisfied. In the step (3), in the situation where it is determined that the measured water quality control parameter satisfies the water quality control parameter in the step (2), the treated sewage in the attached purification facility of the step (1) is used. And drain into the drainage channel leading to the natural environment water area. Furthermore, in this step (3), in a situation where it is not determined that the measured water quality control parameter satisfies the water quality control parameter in the step (2), it is provided downstream from the index measuring instrument While stopping the discharge to the drainage flow path reaching the natural environment water area by the flow path switching valve, the wide area where the municipality using the water supply facility or the neighboring local government cooperated with the sewage purified by the attached purification facility It is fed from the flow path switching valve to a public sewage flow path leading to the sewage purification treatment facility operated by the Union, or is circulated from the flow path switching valve to the attached purification plant.

  In this form of sewage discharge method, only the sewage actually purified to the discharge allowable water quality meeting the water quality control parameter is discharged to the natural environment water area. That is, it is possible to prevent the purified sewage which is uncertain whether it is the discharge allowable water quality because the measurement result of the water quality control parameter is not obtained, from being discharged into the natural environment water area. As a result, according to the sewage discharge method of the above-mentioned form, it is possible to further improve the reliability of the release of the purified sewage to which the allowable water quality of the discharge is secured to the natural environment water area. Further, according to the sewage discharge method of the above embodiment, the amount of sewage discharged to the natural environment water area can be prevented from being discharged to the sewage purification treatment facility, which can contribute to the reduction of the purification load in the sewage purification treatment facility.

  The above-mentioned clean water is not only clean water supplied from a clean water facility for supplying clean water, but also can be well water pumped up by a clean water facility or a nearby facility or spring water led from a spring water source. The well water and the spring water are generally of the same quality as the fresh water supplied from a clean water facility for supplying clean water, and therefore they can be used in place of, or in combination with the clean water. In addition, non-clean water such as stored rain water or industrial water is purified to the same quality as that of clean water supplied from a clean water facility to supply clean water, and the purified water is substituted for the clean water. Alternatively, it can be used in combination with the fresh water.

  (2) In the sewage discharge method of the above aspect, the attached purification facility used in the step (1) is capable of purifying the total amount of the sewage discharged from the facility using the clean water until the dischargeable water quality is achieved. In the step (1), the entire amount of the sewage discharged from the facility for using fresh water may be taken. In this way, the sewage purified by the attached purification facility is only discharged to the sewage purification treatment facility only under the condition where it is not determined that the water quality control parameter is satisfied. As a result, it is possible to reduce costs associated with sewage discharge to the sewage purification treatment facility.

  (3) In the sewage discharge method according to any one of the above aspects, the index measuring instrument used in the step (2) is required to obtain a determination that the measured water quality control parameter satisfies the water quality control parameter. The water quality control parameter is repeatedly measured at the measurement timing exceeding the determination required time, and in the step (2), the determination that the measured water quality control parameter satisfies the water quality control parameter continues for a predetermined number of times If it is obtained, it may be determined that the measured water quality control parameter satisfies the water quality control parameter. In this way, it is possible to ensure that only the purified sewage that has been purified to the discharge water quality can be discharged to the natural environment water area.

  (4) In the sewage discharge method according to any one of the above aspects, in the step (2), the sewage purification treatment facility purifies the water quality control parameter for purifying the taken sewage to the discharge allowable water quality. It may be an index that conforms to the water quality control parameter that defines the treated sewage. In this way, the water quality of the purified sewage that is purified by the attached purification facility and discharged to the natural environment water area can be made similar to the water quality of the sewage that is purified and discharged by the sewage purification treatment facility. Sewage purification can be secured more reliably until the effluent quality becomes acceptable.

  (5) In the sewage discharge method according to any one of the above aspects, in the step (1), the measured water quality control parameter determined that the determination that the water quality control parameter is satisfied in the step (2) is not obtained. On the side where the water quality control parameter is satisfied, at least one of the incremental injection of the purification liquid and the purification activity control of the purification device may be performed. In this way, sewage purification can be achieved at an early stage until the discharge to the natural environment water area becomes an acceptable discharge quality.

  (6) According to another aspect of the present invention, there is provided a sewage purification system for a tap water using facility that discharges sewage generated using tap water. The sewage purification system is a sewage purification system in a facility for using drinking water that discharges sewage generated using drinking water, which takes in the sewage discharged from the facility using water for drinking, and takes out the collected sewage, The attached purification facility purifies the attached purification facility that can be purified to the discharge allowable water quality that allows discharge into the natural environment water area, and the water quality control parameters used to determine the discharge allowable water quality of the withdrawn sewage A parameter determination unit that measures sewage with an indicator and determines whether the measured water quality control parameter measured satisfies the water quality control parameter, and the measured water quality management parameter satisfies the water quality management parameter in the parameter determination unit Discharge the sewage that has been purified by the attached purification facility into the drainage flow path that reaches the natural environment water area. That and a discharge mechanism part. And furthermore, the discharge mechanism section is a flow provided downstream of the index measuring device under the condition that the parameter judging section does not obtain the judgment that the measured water quality management parameter satisfies the water quality management parameter. A wide area coalition where the drainage to reach the natural environment water area is stopped by the road switching valve, and the sewage purified by the attached purification facility is linked to the local government using the water supply facility or a neighboring local government Are fed from the flow path switching valve to a public sewage flow path leading to a sewage purification treatment facility operated by the U.S., or circulated from the flow path switching valve to the attached purification plant.

  This form of sewage purification system also makes it possible to further enhance the reliability of the release of purified sewage to the natural environment water area, which guarantees dischargeable water quality, and also purifies the amount of sewage discharged into the natural environment water area. Preventing discharge into the treatment facility can contribute to the reduction of the purification load at the sewage purification treatment facility.

  The present invention can also be realized in various forms other than the sewage discharge method. For example, a sewage purification system including a facility purification device disposed at a facility using water supply, a computer program for realizing a method of discharging sewage, a non-transitory storage medium recording the computer program, etc. It can be realized in a form.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the outline | summary of the sewage purification system which practices the sewage discharge method as embodiment of this invention. It is an explanatory view functionally showing the composition of a purification control device. It is a flowchart which shows the procedure of purification control of the attached purification facility performed by the purification control apparatus. It is a flowchart which shows the procedure of discharge control of the attached purification facility performed by the purification control apparatus in the steady operation mode.

  FIG. 1 is a block diagram showing an outline of a sewage purification system JGS for practicing a sewage discharge method according to an embodiment of the present invention. As illustrated, this sewage purification system JGS is equipped with an attached purification facility 50 in the facility for using water JY. The water supply facility JY shown in this embodiment is a large-scale complex facility with a commercial facility zone for product display and sales to customers, an entertainment facility zone such as a game arcade and movie theater, and a restaurant etc. is there. And, this facility for using water JY is supplied by the water supply facility JS, which is run by the wide area coalition where the local government to which the facility belongs or a neighboring local government cooperates to plan the water supply, supplies water through the water supply channel JSp. Receive and use the supplied water to discharge the used water as sewage. The facility for using water JY may be equipped with the attached purification facility 50, and is not limited to a large-scale complex facility. For example, in addition to commercial and industrial water and sewage use facilities such as factories and bathing facilities, water and water use facilities such as single-family general dwellings and multiple dwelling houses may be used.

  The facility for using water JJ includes the water distribution channel 20 connected to the water channel JSp, and measures the flow rate of the water supplied from the water channel JSp upstream of the channel, measuring the water flow rate The apparatus 10 is provided. The flush water flow rate measuring device 10 constantly measures the flush water flow rate JQ per unit time. The measurement result is transmitted to the water and sewage utilization status investigation device (not shown) every predetermined time, and is used to investigate the utilization status of the water. The measuring mechanism of the water flow rate measuring device 10 can be in various forms, and in addition to a non-contact type measuring device that measures the flow rate using ultrasonic waves, a screw or a water wheel is rotated in a flow passage It can be a contact-type measuring device that measures the flow rate.

  The facility using water JY distributes drinking water to the toilets in the above zones, water taps such as cooking grounds, water tanks, fountains, cooking equipment and the like using the flush water distribution channel 20. The tap water using facility JY collects the tap water after use in the collective sewage flow passage 30 extending from the sewage outlet in the facility, and then flows it to the in-facility sewage flow passage 40. The in-facility sewage flow passage 40 is connected to a public sewage flow passage Gp leading to a sewage purification treatment facility GJP operated by a wide area coalition where the municipality to which the facility JY belongs belongs or a neighboring municipality cooperates. Therefore, the facility for using fresh water JY discharges the used fresh water collected in the combined sewage flow passage 30 as sewage to the sewage purification treatment facility GJP via the in-facility sewage flow passage 40 and the public sewage flow passage Gp. This sewage purification treatment facility GJP is not only part or all of the other facilities not shown in the figure that use the above facility JY and other facilities such as the above facility JY, but also from a plurality of general residences H and factories F etc. Through the public sewage flow path Gp, receive used clean water to treat it as sewage. Then, the sewage purification treatment facility GJP receives the sewage received from each facility in this way, and the discharge allowable water quality where discharge to the natural environment water region Rgjp, which is a river or other public water area or water area around the purification treatment facility, is permitted. After being purified to the end, the purified sewage is discharged and released to the natural environment water area Rgjp.

  In addition, the facility using water JY uses the sewage distribution valve 42 installed in the sewage flow path 40 in the facility, the attached purification facility 50 attached to the facility using water JY, the purification control device 60, and the attached purification facility 50. An attached drainage flow passage 52 extending, a flow passage switching valve 70 and a sewage flow rate measuring device 80 provided in the flow passage, and a reflux purification flow passage 72 extending from the flow passage switching valve 70 to the sewage inlet of the attached purification facility 50; And a return discharge flow path 73 extending from the flow path switching valve 70 to the merging valve 43 of the in-facility sewage flow path 40. The sewage distribution valve 42 is driven and controlled by the purification control device 60 described later, and takes in at least a part of the sewage discharged from the facility using water JY in the public sewage passage Gp in front of the public sewage passage Gp The intake sewage is distributed and led to the attached purification facility 50. In this case, the purification control device 60 distributes the sewage according to the purification capacity (flow rate capable of purification treatment) of the attached purification facility 50, the total amount of sewage discharged from the facility using water JY, the regulation or request from the local government etc. The valve 42 is driven and controlled to determine the distribution sewage flow rate (intake flow rate) to the attached purification facility 50. The sewage distribution valve 42 can also take in the entire amount of sewage flowing through the in-house sewage flow passage 40 and lead it to the attached purification facility 50.

  The attached purification facility 50 is a facility built in or around the site of the water treatment facility JY separately from the sewage purification treatment facility GJP, and in addition to pH adjustment, biological oxygen concentration (BOD) and chemical oxygen In order to reduce the concentration of oxygen (COD) and other oxygen related to the preservation of living environment, remove or reduce suspended solids (SS) by methods such as sedimentation and separation, remove heavy metals by adsorption, and remove or reduce organic phosphorus and other organic substances, etc. It has multiple aeration tanks, settling tanks, and chemical treatment tanks. And, under the control of the purification control device 60 described later, the attached purification facility 50 is a river or other public water area or sea area around the facility using water under the control of the purification control device 60 described later.・ The purified sewage is purified to the discharge allowable water quality that discharge to environmental water area Rjp1 is permitted, and the purified sewage is discharged to natural environment water area Rjp1 through attached drainage flow path 52 and out-of-facility drainage flow path 53 downstream of it Drain. The attached purification facility 50 of the present embodiment has a purification capacity capable of purifying the entire amount of sewage discharged from the facility using water JY to the discharge allowable water quality.

  The above-mentioned attached purification facility 50 purifies it according to the total amount of water consumption, total sewage discharge, site area, etc. per unit period (for example, one day, one week, one month) of the water use facility JY Capacity and size are determined. For example, the attached purification facility 50 may discharge about 5 to 100% of the total sewage discharge of the water use facility JY per unit period as described above, and the allowable water quality for discharge to the natural environment water area Rjp1 described above. The purification performance and capacity that can be purified until it is said to be of scale. In this case, since the water supply facility JY of this embodiment is a large-scale complex facility including a commercial facility zone and the like as described above, the planned or actual total sewage discharge volume is large. Although the scale of the purification facility 50 is determined within the above range, if the total sewage discharge amount is small, the facility scale and capacity of the attached purification facility 50 may be increased in the total sewage discharge ratio. For example, if the facility JY used for water supply is an apartment or apartment complex, small-scale factory, commercial building, etc., about 30 to 100% of the total sewage discharge for the attached purification facility 50 attached to the facility What is necessary is just to be the purification performance and ability, and the scale which can purify the sewage to the discharge allowable water quality which allows the discharge to the natural environment water area Rjp1.

  In addition, the attached purification facility 50 is provided with an index measuring unit 54 for measuring the degree of water purification of the sewage purified in the aeration tank, the settling tank, and the chemical treatment tank described above. The index measuring instrument 54 is disposed in the treated water storage area 51 in the lowermost basin of the attached purification facility 50, samples the sewage in the treated water storage area 51, and performs various treatment tanks such as aeration tank of the attached purification facility 50. Measure the water quality control parameters of the purified sewage (hereinafter, this sewage is simply referred to as purified sewage). Water quality control parameters include hydrogen ion index (pH), suspended solids (SS), biological oxygen concentration (BOD), chemical oxygen concentration (COD), total organic carbon (TOC: Total Organic Carbon), animal and vegetable fats and oils Content, copper content, zinc content, etc. are included. In the present embodiment, among the above-mentioned water quality control parameters, as the water quality control parameters for purifying hydrogen ion concentration (pH), suspended solids mass (SS) and total organic carbon (TOC) to the discharge allowable water quality, It measured using a measuring instrument. These water quality control parameters are used to determine the discharge allowable water quality of the sewage purified by the attached purification facility 50. Although biological oxygen concentration (BOD) and chemical oxygen concentration (COD) may be measured, BOD measurement requires five days of culture in an aerobic environment. I did not measure it. Total organic carbon (TOC) is an index that expresses the amount of organic matter in water as carbon concentration, and can be correlated with BOD and COD. Therefore, in this embodiment, the measurement of COD is omitted in addition to BOD.

・ Indicator 1. Hydrogen ion concentration (pH): HORIBA Advanced Techno Co., Ltd. hydrogen ion index meter: Measurement result acquisition time required 0.1 minute;
・ Indicator 2. Suspended material mass (SS): Suspended substance measuring device manufactured by HORIBA Advanced Techno Co., Ltd .: Measurement result acquisition time required 0.3 minutes;
・ Indicator 3. Total organic carbon (TOC): Toray Engineering Co., Ltd. organic carbon analyzer: Measurement result acquisition time required 4 minutes;

  The above-mentioned various water quality control parameters obtained by the index measuring instrument 54 are actual water quality control parameters measured in the treated water storage area 51 on the most downstream side of the attached purification facility 50, so So, it is a water quality control parameter of the purified sewage which is going to be discharged to natural environment water area Rjp1 from now on. In the present embodiment, according to the actual water quality control parameters measured by the index measuring instrument 54, the propriety of the discharge of the purified sewage to the natural environment water area Rjp1 is determined as described later. The actual water quality control parameter measured by the measuring instrument 54 is referred to as a measured water quality control parameter, and is distinguished from the water quality control parameter defined by the sewage purification treatment facility GJP.

  The treated water storage area 51 in which the index measuring instrument 54 is disposed has a volume capable of storing the purified sewage purified over a predetermined time by the attached purification facility 50. Then, the attached drainage channel 52 guides the purified sewage stored in the treated water storage area 51 from the purified sewage that has previously flowed into the treated water storage area 51 into the extra-plant drainage channel 53. The storage volume of the treated water storage area 51 will be described later.

  The water supply facility JY and the sewage purification treatment facility GJP are separated only by the route of the public sewage flow passage Gp, but the route length of the public sewage flow passage Gp is generally not so long. Therefore, natural environment water area Rjp1 which is the discharge / discharge place of the purified sewage of attached purification facility 50, and natural environment water area Rgjp which is the discharge / discharge place of purified sewage of sewage purification treatment facility GJP, for example, is the same river. It is often the relationship between the upper and lower basins, and the main stream and the tributaries. The sewage purification by the attached purification facility 50 will be described later together with the control by the purification control device 60.

  The flow path switching valve 70 is driven under the control of the purification control device 60 described later, and the discharge destination of the purified sewage of the attached purification facility 50 is the drainage channel 53 outside the facility following the attached drainage channel 52 or the attached purification It switches to the facility 50 or the in-facility sewage channel 40. That is, the flow path switching valve 70 switches the flow path to the attached drainage flow path 52 under the purified water quality securing condition described later, and the out-of-facility drainage flow path reaching the natural environment water area Rjp1 to the cleaned sewage of the attached purification facility 50 Discharge to 53 In addition, the flow path switching valve 70 closes the flow path reaching the drainage flow path 53 outside the facility under the condition where the purified water quality is not secured, which will be described later, and then the flow path is either the reflux purification flow path 72 or the return discharge flow path 73 Switch to either or both. Thereby, under the below-mentioned situation where the purification water quality is not secured, the purified sewage of the attached purification facility 50 is sent to the public sewage passage Gp via the return discharge passage 73 and the merging valve 43 or Reflux from the water inlet. When the flow path switching valve 70 switches the flow path to both the reflux purification flow path 72 and the return discharge flow path 73, the flow rate ratio is set. Such flow path switching and flow rate ratio setting by the flow path switching valve 70 are controlled by the purification control device 60 as described later.

  The sewage flow rate measuring device 80 is installed in the route of the attached drainage channel 52 connected to the drainage channel 53 outside the facility, and is discharged to the natural environment water area Rjp1 through the attached drainage channel 52 and the drainage channel 53 outside the facility. The sewage flow rate, that is, the flow rate when the purified sewage of the attached purification facility 50 is discharged to the natural environment water area Rjp1 is measured. The sewage flow rate measuring device 80 constantly measures the purified sewage flow rate SGQ per unit time, as in the case of the water flow rate measuring device 10 described above. The measurement result is transmitted to the water and sewage utilization status investigation device (not shown) every predetermined time, and is used to investigate the utilization status of the water. The measuring mechanism of the sewage flow rate measuring device 80 and the transmission of the purified sewage flow rate SGQ and the facility identification data as the measurement result are the same as the water flow rate measuring device 10.

  Next, the purification control device 60 will be described. FIG. 2 is an explanatory view functionally showing the configuration of the purification control device 60. As shown in FIG. The purification control device 60 controls the state of the sewage purification by the attached purification facility 50, controls the intake of water from the sewage distribution valve 42, and controls the circulation of the sewage through the flow path switching valve 70, and the like. Then, the purification control device 60 includes a control device 62, a data updating unit 63, various sensor groups 64, various driving device groups 66, and a water discharge regulation database 68 in order to achieve such control.

  The control device 62 is configured using a so-called personal computer, and bears each control described above by the CPU, the RAM, the ROM and the processing described later of the computer. Further, the control device 62 inputs various measured water quality control parameters measured by the index measuring instrument 54, and performs water quality purification necessity determination and valve drive control using the measured water quality control parameters as described later. The data updating unit 63 is connected to an external data communication network, for example, the Internet NW, acquires water discharge control information and water quality control parameters at any time via the Internet NW, and updates the stored contents of the water discharge control database 68 described later. . The sensor group 64 includes a sensor (for example, a pH sensor, an oxygen concentration sensor, a water level sensor, etc.) that measures the purification status and the device driving status of each treatment tank of the attached purification facility 50, the water flow measuring device 10 described above The receiving apparatus of the flow volume data which the sewage flow measurement apparatus 80 transmits, etc. are included. The driving device group 66 includes, for example, the aeration device, the stirring device, the water feeding device, and the like included in the attached purification facility 50, the sewage distribution valve 42 and the flow path switching valve 70 described above.

  The water discharge control database 68 is configured of a storage medium capable of reading and writing data from the outside, such as a hard disk drive and other media, and is connected to the control device 62. The water discharge control database 68 includes various water quality control parameters, such as pH and TOC described above, for purifying up to the discharge allowable water quality that allows discharge to the natural environment water area Rjp1 around the facility JY using fresh water. In addition to the regulation range, the floating material removal regulation range, the upper limit value of the discharge (discharge amount) to the natural environment water area Rjp1, the presence or absence of a request for emergency water stop at the time of river flooding, etc. are stored. The above-mentioned water quality control parameters are also used for sewage purification in the sewage purification treatment facility GJP operated by the local government or wide area association to which the facility JY using water belongs. In the present embodiment, in order to achieve the same sewage purification as the sewage purification by the sewage purification treatment facility GJP even in the attached purification facility 50, the above-mentioned data updating unit 63 acquires water quality control parameters from the sewage purification treatment facility GJP as needed. , And store them in the water discharge regulation database 68 as needed. In this case, if the water quality control parameters of the sewage purification treatment facility GJP are not disclosed, it is sufficient to obtain and update the water quality control parameters from the sewage purification treatment facility GJP through a dedicated line or the like from the viewpoint of water quality preservation. The water quality control parameter corresponds to the measured water quality control parameter of the index measuring instrument 54. In addition, it is not necessary to make it completely the same as the water quality control parameter adopted by the sewage purification treatment facility GJP, and if it is possible to purify the discharge allowable water quality that discharge to the natural environment water area Rjp1 around the facility using water JY is permitted The water quality control parameter of the attached purification facility 50 can be made looser or stricter than the water quality control parameter adopted by the sewage purification treatment facility GJP. The purification control device 60 described above performs the switching control of the flow path switching valve 70 while using the measurement result of the index measuring instrument 54 as the purification control of the attached purification facility 50, and therefore together with the index measuring instrument 54 and the flow path switching valve 70 , And the parameter determination unit and the discharge mechanism unit.

  FIG. 3 is a flowchart showing the procedure of purification control of the attached purification facility 50 executed by the purification control device 60. As shown in FIG. The purification control to be illustrated is for controlling the drive of the attached purification facility 50 according to each operation mode after determining the operation mode of the attached purification facility 50, and is repeatedly executed by the purification control device 60. In this purification control, first, following the reading of the operation mode factor that determines the operation mode of the attached purification facility 50 (step S100), the operation mode in which the attached purification facility 50 should be operated is the steady operation mode It is determined (step S110). In the attached purification facility 50 used in the sewage discharge method of this embodiment, the steady operation mode under the condition that the water quality of the purified sewage meets the discharge allowable water quality suitable for discharge to the natural environment water area Rjp1, and the natural environment water area Rjp1 The drive control is performed in one of the emergency water stop mode in the case where a flood of rivers is assumed and the stop mode in which the operation stop is requested by maintenance inspection and the like. The emergency water stop mode is determined by the emergency water stop factor shown in FIG. 2, and the stop mode is determined by the operation of a control stop switch (not shown), etc. If both modes are not determined, the steady operation mode It becomes. Therefore, in the reading of the operation mode factor in step S100, the reading of the setting status of the emergency water stopping factor shown in FIG. 2 and the operation scan such as the control stop switch are performed.

  If the emergency stop factor is not set in the reading of the operation mode factor in step S100 and there is no operation of the control stop switch or the like, in step S110, the purification control device 60 operates the steady operation mode as the current operation mode. Thus, the attached purification facility 50 is driven and controlled in the steady operation mode as follows (step S120). In step S120, the purification control device 60 drives and controls the sewage distribution valve 42 so that the intake sewage flow rate from the sewage distribution valve 42 falls within 50 to 80% of the purification processing flow rate of the attached purification facility 50. In this way, by performing intake control under steady control, the sewage flow rate to be cleaned into the attached purification facility 50 has room for the flow rate of the sewage to be purified, and the excessive load operation of the attached purification facility 50 is avoided. Improve purification performance and maintain high purification capacity. Further, the purification control device 60 drives and controls the aeration equipment and the like of the attached purification facility 50 in a steady state while reading the water quality control parameters as a management target from the water discharge control database 68 shown in FIG. The sewage that has entered the attached purification facility 50 is purified by the attached purification facility 50. At this time, the purification control device 60 also reads the actual measured water quality control parameters obtained from the index measuring instrument 54 in the treated water storage area 51 on the most downstream side of the attached purification facility 50 and uses the both water quality management parameters Feedback control or feed forward control is performed on 50 aeration devices and the like. In addition, the intake amount of sewage from the sewage distribution valve 42 may be increased in a closing period, a holiday, or the like, in consideration of the operation status of the facility JY using fresh water. In addition, the intake amount of sewage from the sewage distribution valve 42 may be the total amount of sewage flowing through the in-facility sewage flow passage 40. The intake sewage flow rate from the sewage distribution valve 42 may be 50 to 80% of the purification treatment flow rate of the attached purification facility 50, or the intake sewage flow rate may be 100% of the purification treatment flow rate.

  The control of the attached purification facility 50 in step S120 is control of equipment related to sewage purification. Therefore, the purification control device 60 performs discharge control under steady operation involved in discharge of the purified sewage following step S120 (step S130). FIG. 4 is a flow chart showing a procedure of discharge control of the attached purification facility 50 executed by the purification control device 60 in the steady operation mode.

  The discharge control in the steady operation mode is a control to determine the discharge destination of the cleaned sewage of the attached purification facility 50 each time, and first, an index for measuring the water quality control parameter in the treated water storage area 51 in the attached purification facility 50 It is determined whether the measurement standby time until obtaining the measured water quality control parameter from the measuring instrument 54 has passed (step S131). The measurement standby time to be judged in step S131 is the judgment required time necessary to obtain the judgment that the measured water quality control parameter satisfies the water quality control parameter, and each time corresponding to index 1 to index 3 above. It is a time which is several seconds longer than the longest required time of the required time (required time for measurement result acquisition) required to measure the water quality control parameter corresponding to each measuring instrument included in the index measuring instrument 54 for each water quality control parameter. And each measuring instrument which index measuring instrument 54 has for every water quality control parameter of index 1-index 3 starts the measurement of the water quality control parameter at the measurement timing corresponding to the longest required time for the water quality control parameter of index 3 As soon as the measurement result is obtained, the measurement result, that is, the measured water quality control parameter is output to the purification control device 60. Therefore, the purification control device 60 acquires all of the measured water quality control parameters of the indicators 1 to 3 from the index measuring instrument 54 for each measurement standby period, and acquires the acquired measured water quality control parameters of the water discharge regulation database 68 (see FIG. 2) Memorize and save. That is, all the measured water quality control parameters of index 1 to index 3 are obtained at the measurement timing exceeding the above-mentioned measurement result acquisition required time.

  If it is determined in step S131 that the measurement elapsed time has not elapsed, all measured water quality control parameters for the water quality control parameters of index 1 to index 3 have not been obtained, so the purification control device 60 The exhaust control routine of FIG. 4 and the purification control routine of FIG. 3 are once ended. As described above, when the control routine ends after the negative determination in step S131, the discharge destination of the purified sewage of the attached purification facility 50 is maintained at the discharge destination defined in the previous control routine. For example, if the discharge destination specified in the previous control routine is the extra-plant drainage channel 53 reaching the natural environment water area Rjp1, the drainage destination of the purified sewage of the attached purification facility 50 is the extra-plant drainage channel 53, The purified sewage is discharged to the natural environment water area Rjp1 through the drainage flow path 53 outside the facility. In addition, in the period in which the measurement elapsed time has not passed, the purified water quality is undecided and the purified water quality is not secured yet.

By the way, since the sewage purification in the steady operation mode of step S120 described above is performed in the attached purification facility 50 even under the above-mentioned situation where the purified water quality is not secured in the measurement standby period described above, it is used in the sewage discharge method of this embodiment In the attached purification facility 50, the following measures are taken. The attached purification facility 50 has the treated water storage area 51 in the lowermost basin, and the storage volume of the purified sewage in the treated water storage area 51 is purified by the attached purification facility 50 over the above measurement standby time. It has a volume capable of storing purified sewage. Therefore, according to the attached purification facility 50 used in the sewage discharge method of the present embodiment, purification conducted by the attached purification facility 50 until all the measured water quality control parameters corresponding to the water quality control parameters of index 1 to index 3 are obtained. Even if the discharge destination is defined as the extra-plant drainage flow path 53 in the previous control routine, the pre-treated sewage can be prevented from being discharged to the natural environment water area Rjp1 via the extra-plant drainage flow path 53. For example, if the purification capacity of the attached purification facility 50 is 100 m ³ / h, the purified sewage that has been purified over the measurement standby time will be about 6.7 m ^3, and the storage volume of the treated water storage area 51 It is sufficient if the volume to which the purified sewage can be stored, for example, 7 to 10 m ³ .

  If the purification control device 60 makes a positive determination that the measurement elapsed time has elapsed in step S131, it reads the measured water quality control parameters already acquired from the index measuring instrument 54 and stored in the water discharge regulation database 68 (step S132). Next, the purification control device 60 determines whether the read measured water quality control parameter satisfies the water quality control parameter stored in the water discharge control database 68 (step S133). If it is determined in step S133 that the measured water quality control parameter satisfies the water quality control parameter stored in the water discharge control database 68, the purification control device 60 measures the current measurement following the previous discharge control routine of FIG. It is determined whether the water quality control parameter continues and satisfies the water quality control parameter (step S134). Then, if it is determined that the measured water quality control parameter continues and the water quality control parameter is satisfied continuing from the previous time, the purification control device 60 performs flow path switching under steady state (step S135), and this routine Stop once. The flow path switching under this steady state is controlled so that the flow path switching valve 70 is switched so that the discharge destination of the purified sewage by the attached purification facility 50 becomes the natural environment water area Rjp1 passing through the external drainage flow path 53 in FIG. It is done by doing.

  On the other hand, when it is determined in step S133 that the measured water quality control parameter does not satisfy the water quality control parameter in step S133, the present measured water quality control parameter continues in step S134 and the water quality control parameter is satisfied. If it is determined not to be present, the purification control device 60 controls the flow rate switching under unsteady state by increasing the injection of the purification chemical solution to enhance the sewage purification more than the current situation and the purification activity control of the purification device (step S136). Step S137) is sequentially performed, and this routine is once ended. Since the incremental injection of the purification chemical solution in step S136 is, for example, a high measured value of TOC, the purification chemical solution that causes the decrease of organic matter is treated on the side where TOC satisfies the water quality control parameters related thereto. Increment in the tank is to inject. In addition, the purification activity control of the purification device controls the agitator, which is the purification device, at high rotation speed to increase the removal of suspended solids by a filter or the like, or controls the aeration device at high speed to activate aeration in the aeration tank. And so on. In the flow channel switching of step S137 under unsteady state, the discharge destination of the purified sewage of the attached purification facility 50 is either or both of the reflux flow channel 72 and the return discharge channel 73 in FIG. 1. As described above, switching control of the flow path switching valve 70 is performed. In the case where the discharge destination of the purified sewage of the attached purification facility 50 is both flow paths of the reflux purification flow path 72 and the return discharge flow path 73, the discharge flow rate to the reflux purification flow path 72 and the discharge flow to the return discharge flow path 73 The discharge flow rate is defined by the flow channel opening degree setting in the flow channel switching valve 70 under the control of the purification control device 60. The flow rate ratio of the above two flow rates may be a flow rate ratio defined in advance, and may be variably controlled as appropriate according to the amount of sewage intake to the attached purification facility 50 at the present time.

  If it is determined in step S133 that the measured water quality management parameter does not satisfy the water quality management parameter, and if it is determined in step S134 that the current measured water quality management parameter continues not to satisfy the water quality management parameter. In the above, the lighting of a warning lamp for notifying that the parameter is not satisfied, text display, and alarm sound generation may be performed. In this way, the facility manager who recognizes that the parameter is not sufficient can check the execution status of the injection of the purification liquid at step S136 and the purification activity control of the purification device, and the flow channel switching state at step S137. Also, instead of the increased injection of the purification chemical solution by the purification control device 60 and the purification activity control of the purification device and the flow path switching, the facility manager can substitute for these actions.

  Next, the purification control of the attached purification facility 50 in the operation mode other than the above-described steady operation mode will be described by returning to FIG. If it is determined in step S110 described above that the current operation mode is not the steady operation mode from the setting status of the emergency water blocking factor and the operation status of the control stop switch etc., the purification control device 60 requests the emergency water blocking. It is determined whether there is any (step S140). This determination is made based on the setting condition of the emergency water stop factor, and when the emergency water stop factor is set, the purification control device 60 controls the attached purification facility 50 to operate in the emergency water stop mode (step S150) ), This routine is ended once. This emergency water stop mode is, for example, an operation mode that is adopted when a flood of a river is assumed in the natural environment water area Rjp1, and the natural water area Rjp1 has been cleaned in the attached purification facility 50. No, let's not discharge that purified sewage. That is, after reducing the intake sewage flow rate by the sewage distribution valve 42, the purification control device 60 drives and controls the attached purification facility 50 in the emergency water stop mode so as to clean the attached purification facility 50 in an idle state. The emergency water stop factor is set by a request from a local government or a wide area union, or is set by river condition data issued from a river management association or the like. Further, as for the discharge destination of the purified sewage, the flow path switching valve 70 is switched and controlled so that the whole amount of sewage flowing through the attached drainage flow path 52 is circulated in the reflux purification flow path 72. By doing this, while keeping the attached purification facility 50 in an idle state for continuous purification operation, the purified sewage will not be discharged to the natural environment water area Rjp1 via the attached drainage flow passage 52 and the extra-plant drainage flow passage 53. You can In this case, the intake from the sewage distribution valve 42 is stopped so that the overflow of the attached purification facility 50 does not occur due to the reflux from the reflux purification channel 72, and the attached purification facility 50 is cleaned in an idle state by the closed system It is also possible to drive or stop control temporarily. Alternatively, the return discharge flow path 73 may be added to the discharge destination of the purified sewage, and the purified sewage may be discharged to the public sewage flow path Gp from the return discharge flow path 73 through the merging valve 43. In addition, in the idle purification operation of the attached purification facility 50 mentioned here, purification treatment such as sewage circulation and aeration in each tank in the attached purification facility 50 is performed near the lower limit of the operating range of the drive device Means

  In step S160 following the negative determination in step S110 and the negative determination in step S140, the purification control device 60 stops the attached purification facility 50 in that the current operation mode is requested to be stopped by the operation of the control stop switch or the like. The drive control is performed at step S150, and this routine is temporarily ended. This stop mode is an operation mode corresponding to the request for operation stop by maintenance inspection of the attached purification facility 50, etc., and after stopping the water intake by the sewage distribution valve 42, the operation of the attached purification facility 50 is also temporarily performed. Stop. By doing this, the sewage is prevented from flowing into the attached purification facility 50 requiring maintenance inspection, and all sewage from the facility using water JY is regarded as unpurified sewage, and the in-facility sewage flow passage 40 and the public sewage flow. It can be discharged to the sewage purification treatment facility GJP via Road Gp. In addition, the sewage remaining in the attached purification facility 50 is forcibly discharged from the return discharge flow passage 73 through the public sewage flow passage Gp to the sewage purification treatment facility GJP by a pump or the like (not shown) set in the attached purification facility 50. It is also good.

  In the sewage purification system JGS to which the sewage discharge method of the present embodiment described above is applied, when the sewage discharged from the facility using water JY is purified by the attached purification facility 50 and discharged to the natural environment water area Rjp1, If the measured water quality control parameters measured by the index meter 54 for the purified sewage of the facility 50 continue to satisfy the water quality management parameters (Step S134: affirmative determination), the purified sewage of the attached purification facility 50 is After the flow path switching by the flow path switching valve 70, the natural environment water area Rjp1 is discharged (step S135). Moreover, in the sewage purification system JGS to which the sewage discharge method of this embodiment is applied, the measured water quality control parameters measured by the index measuring instrument 54 for the purified sewage of the attached purification facility 50 do not satisfy the water quality control parameters. Then (step S134: negative determination), while stopping the discharge to the natural environment water area Rjp1 by the flow path switching valve 70 provided downstream of the index measuring instrument 54, the purified sewage of the attached purification facility 50 is treated as a sewage purification treatment It is sent from the flow path switching valve 70 to the public sewage flow path Gp reaching the facility GJP, or is circulated from the flow path switching valve 70 to the attached purification plant 50 via the reflux purification flow path 72 (step S137). Therefore, according to the sewage purification system JGS to which the sewage discharge method of the present embodiment is applied, only the sewage actually purified to the discharge allowable water quality satisfying the water quality control parameter by the above-described discharge destination switching of the purified sewage It is possible not to discharge to water area Rjp1. This point will be described in detail below.

  If the measured water quality control parameters obtained from the index measuring instrument 54 for each measurement standby time continue to satisfy the water quality control parameters (Step S134: affirmative determination), the measured water quality control parameters satisfy the water quality control parameters. The purified sewage meets the allowable discharge quality over the measurement waiting time for the number of continuations. Therefore, in this case, only the sewage actually purified to the discharge allowable water quality is discharged to the natural environment water area Rjp1.

  Also, the measured water quality control parameters obtained from the index measuring instrument 54 in the previous control routine do not satisfy the water quality control parameters, and the measured water quality control parameters obtained from the index measuring instrument 54 in this control routine are water quality control In the measurement standby time when the parameters are satisfied, that is, the measurement standby period during the water quality improvement transition, after the negative determination in step S131, the discharge destination of the purified sewage of the attached purification facility 50 is specified in the previous control routine. The discharge destination is maintained. In this case, since the measured water quality control parameter did not satisfy the water quality control parameter, the discharge destination specified in the previous control routine does not satisfy the water quality control parameter. Since the purification flow path 72 or the return discharge flow path 73, this discharge destination is maintained. Therefore, the purified sewage is not discharged to the natural environment water area Rjp1 in the measurement standby period when the water quality is improved. And it is unclear whether the purified sewage in the measurement standby period at the time of the water quality improvement transition has been purified to the discharge allowable water quality, but it is discharged to the reflux purification flow channel 72 or the return discharge flow channel 73 It is not discharged to the natural environment water area Rjp1 through the drainage flow path 53. This is synonymous with the fact that only the sewage that has been actually purified to the discharge allowable water quality is discharged to the natural environment water area Rjp1.

  In addition to this, the measured water quality control parameters obtained from the index measuring instrument 54 in the previous control routine satisfy the water quality control parameters, and the measured water quality control parameters obtained from the index measuring instrument 54 in this control routine are water quality In the measurement standby time when the management parameter is not satisfied, that is, in the measurement standby period when the water quality declines, after the negative determination in step S131, the discharge destination of the purified sewage of the attached purification facility 50 is the previous control routine. The discharge destination specified in the above is maintained. In this case, since the measured water quality control parameter satisfies the water quality control parameter, the drainage destination 53 that reaches the natural environment water area Rjp1 is maintained as the discharge destination specified in the previous control routine. . However, the treated water storage area 51 stores the purified sewage that has been purified over the measurement standby time when the water quality declines as described above, so the extra-facility drainage channel 53 reaching the natural environment water area Rjp1 is maintained Even if it has been, purified sewage that has been purified over the measurement standby time when the water quality declines will not be discharged into the natural environment water area Rjp1. And it is unclear if the purified sewage in the measurement standby period at the time of this water quality decline transition has been purified to the discharge allowable water quality, but it will be stored and stored in the treated water storage area 51, It is not discharged into the natural environment water area Rjp1. This is also synonymous with the fact that only the sewage actually purified to the discharge allowable water quality is discharged to the natural environment water area Rjp1. As mentioned above, according to the sewage purification system JGS to which the sewage discharge method of this embodiment is applied, the reliability of discharge | release to the natural environment water area Rjp1 of the purified sewage which ensured the discharge allowable water quality can be improved. Moreover, according to the sewage purification system JGS to which the sewage discharge method of this embodiment is applied, the purified sewage of the amount of water discharged to the natural environment water area Rjp1 can be prevented from being discharged to the sewage purification treatment facility GJP. The purification load of the purification processing facility GJP can be reduced. In addition, after the elapse of the measurement standby period at the time of the water quality change transition, the measured water quality control parameter at that time does not satisfy the water quality control parameter, so after receiving a negative determination in step S133 of FIG. The discharge destination becomes the recirculation purification channel 72 other than the facility drainage channel 53 and the return discharge channel 73 (step S136), and is not drained to the natural environment water area Rjp1 through the facility drainage channel 53.

  In the sewage purification system JGS to which the sewage discharge method according to the present embodiment is applied, the attached purification facility 50 has a purification capacity capable of purifying the entire amount of sewage discharged from the facility using water JY to the discharge allowable water quality, The total amount of sewage discharged from the facility using water JY is taken into the attached purification facility 50 to purify the sewage. Therefore, under the situation where the measured water quality control parameter satisfies the water quality control parameter (step S133: under the positive determination situation), the whole amount of purified sewage is discharged to the natural environment waters Rjp1, and the measured water quality control parameter is the water quality control parameter The sewage which has been purified in the attached purification facility 50 is only discharged to the sewage purification treatment facility GJP via the return discharge flow path 73 only under the condition where the condition S1 is not satisfied (step S133: negative determination condition). As a result, according to the sewage purification system JGS to which the sewage discharge method of the present embodiment is applied, the amount of discharged sewage to the sewage purification treatment facility GJP can be reduced, and the sewage cost associated with the sewage discharge can also be reduced.

  In the sewage purification system JGS to which the sewage discharge method of this embodiment is applied, the sewage purification treatment facility GJP has purified the water quality control parameters for purifying the sewage taken by the sewage distribution valve 42 until it becomes the discharge allowable water quality. The indicator follows the water quality control parameters that define sewage. Therefore, the water quality of the purified sewage that is purified by the attached purification facility 50 of the facility JY using water and discharged to the natural environment water area Rjp1 is approximately the same as the water quality of the sewage that is purified by the sewage purification treatment facility GJP. Since it can be done, sewage purification can be secured more reliably until it becomes the discharge allowable water quality to which the discharge to natural environment water area Rjp1 is permitted.

  In the sewage purification system JGS to which the sewage discharge method of this embodiment is applied, if the measured water quality control parameter of the TOC does not satisfy the water quality control parameter, the chemical treatment of the attached purification facility 50 on the side where the TOC satisfies the water quality control parameter In the tank, a large amount of purification chemical solution is injected, or purification activity control of purification equipment such as a stirrer is performed (step S136). For this reason, sewage purification can be achieved at an early stage until the discharge allowable water quality is permitted to be discharged to the natural environment water area Rjp1.

  The present invention is not limited to the above-described embodiment, and can be realized in various configurations without departing from the scope of the invention. For example, the technical features of the embodiment corresponding to the technical features in the respective forms described in the section of the summary of the invention are for solving some or all of the problems described above, or a part of the effects described above It is possible to replace or combine as appropriate to achieve all or all. Also, if the technical features are not described as essential in the present specification, they can be deleted as appropriate.

  In the embodiment described above, if the measured water quality control parameter continues twice and satisfies the water quality control parameter, the discharge destination of the purified sewage of the attached purification facility 50 is switched to the natural environment water area Rjp1 (step S133- 135) When the measured water quality control parameter changes from an unsatisfied state of the water quality control parameter to sufficiency (water quality improvement transition), the discharge destination of the purified sewage of the attached purification facility 50 may be switched to the natural environment waters Rjp1 . Specifically, step S134 shown in FIG. 4 may be omitted. In this way, although it can not be concluded that the purified sewage in the measurement standby time that caused the water quality improvement transition is the discharge allowable water quality that permits discharge to the natural environment waters Rjp1, the water quality has been purified similar to the discharge allowable water quality The flow rate of purified sewage in the measurement standby time is, for example, extremely small compared to the flow rate of sewage that the attached purification facility 50 operating all day purifies and processes. Therefore, if the release of the purified sewage to the natural environment water area Rjp1 is evaluated on a daily basis, even if the discharge destination of the purified sewage is switched to the natural environment water area Rjp1 when the water quality is improved, the discharge is substantially released. It can be said that it is possible to release purified sewage, which has been regarded as acceptable water quality, to the natural environment waters Rjp1. Further, when the measured water quality control parameter satisfies the water quality control parameter continuously three or more times, the discharge destination of the purified sewage of the attached purification facility 50 may be switched to the natural environment water area Rjp1. In this way, the certainty of sewage purification until the discharge allowable water quality that allows discharge to the natural environment water area Rjp1 is further enhanced.

  In the embodiment described above, an index serving as a target of discharge allowable water quality that allows discharge to the natural environment water area Rjp1, index 1: hydrogen ion concentration (pH) and index 2: suspended matter mass (SS), index 3 : Although it was set as total organic carbon (TOC), you may use animal fats and oils content, copper content, zinc content etc. as a parameter | index.

  In the embodiment described above, when the measured water quality control parameter does not satisfy the water quality control parameter, the increase injection of the purification solution to the side where the TOC satisfies the water quality control parameter and the purification activity control of the purification device are performed. Alternatively, one or the other may be used to improve purification.

  In the embodiment described above, the attached purification facility 50 is provided with a plurality of aeration tanks, sedimentation tanks, and chemical treatment tanks, but purification to a discharge allowable water quality that allows discharge to natural environment water areas is possible In this case, a single treatment tank, for example, a treatment tank storing activated carbon in a high temperature environment, may be used, and a purification facility for purifying sewage with this high temperature activated carbon may be used.

DESCRIPTION OF SYMBOLS 10 ... Water flow rate measurement apparatus 20 ... Water distribution flow path 30 ... Collecting sewage flow path 40 ... Facility sewage flow path 42 ... Sewage distribution valve 43 ... Joint valve 50 ... Attachment purification facility 51 ... Treated water storage area 52 ... attachment Drainage flow path 53: Out-of-facility drainage flow path 54: Index measuring instrument 60 ... Purification control device 62 ... Control device 63 ... Data updating unit 64 ... Sensor group 66 ... Drive equipment group 68 ... Water discharge regulation database 70 ... Flow path switching valve 72 ... Recirculation purification flow path 73 ... Return discharge flow path 80 ... Sewage flow rate measurement equipment GJP ... Sewage purification processing facility Gp ... Public sewage flow path H ... General residence F ... Factory JGS ... Sewage purification system JS ... Water supply facility JSp ... Water supply flow Road JY ... water supply facility NW ... Internet Rgjp ... natural environment water area Rjp 1 ... natural environment water area

Claims (5)

A method for discharging sewage at a facility using water that discharges sewage generated using water
A step of taking the sewage discharged from the facility using the fresh water, and purifying the taken sewage with an attached purification facility capable of purifying until the discharge allowable water quality to allow discharge to the natural environment water area (1) When,
The water quality control parameter used to determine the discharge allowable water quality of the taken-in sewage is measured for the purified sewage in the step (1) with an index meter, and the measured water quality control parameter measured is the water quality control parameter A step (2) of determining whether the conditions are satisfied;
In the situation where it is determined that the measured water quality control parameter satisfies the water quality control parameter in the step (2), the sewage that has been purified in the attached purification facility of the step (1) is And a step (3) of discharging to the drainage flow path
Furthermore, in the step (3),
In the situation where the determination that the measured water quality control parameter satisfies the water quality control parameter is not obtained in the step (2), the natural environment water area is provided by the flow path switching valve provided downstream of the index measuring device. Stop the discharge into the drainage flow path that leads to the above, and use the sewage purified by the attached purification facility to a sewage purification treatment facility operated by a wide-area union in which the municipality using the water supply facility or a neighboring municipality cooperates. A method for discharging sewage, which is fed from the channel switching valve to a public sewage channel which reaches or circulated from the channel switching valve to the attached purification facility. The method of discharging sewage according to claim 1, wherein
The attached purification facility used in the step (1) is capable of purifying the entire amount of the sewage discharged from the facility using the fresh water until the dischargeable water quality is achieved,
In the said process (1), the sewage discharge method of taking in water whole quantity of the said sewage discharged | emitted from the said facility using water. The sewage discharge method according to claim 1 or 2, wherein
The index measuring instrument used in the step (2) repeatedly measures the water quality control parameter at a measurement timing exceeding the determination time required to obtain the determination that the measured water quality control parameter satisfies the water quality control parameter. And
In the step (2), when the determination that the measured water quality management parameter satisfies the water quality management parameter is continuously obtained for a predetermined number of times, the measured water quality management parameter determines the water quality management parameter. Sewage discharge method judged to meet. The sewage discharge method according to any one of claims 1 to 3, wherein
In the step (2), the water quality control parameter for purifying the taken-out sewage to the discharge allowable water quality is taken as an index following the water quality control parameter defined for the purified sewage by the sewage purification treatment facility. Sewage discharge method. A sewage purification system in a water supply facility for discharging sewage generated using water supply, comprising:
An attached purification facility capable of taking in the sewage discharged from the facility using the fresh water and purifying the taken sewage to a discharge allowable water quality that allows discharge into the natural environment water area;
The water quality control parameter used to determine the discharge allowable water quality of the taken-in sewage is measured for the purified sewage at the attached purification facility with an index meter, and the measured water quality control parameter meets the water quality control parameter. A parameter determination unit that determines the presence or absence of
In the situation where it is determined that the measured water quality control parameter satisfies the water quality control parameter in the parameter determination unit, the sewage purified by the attached purification facility is discharged to the drainage channel reaching the natural environment water area And a discharge mechanism to
Furthermore, the discharge mechanism unit
In the situation where it is not determined that the measured water quality control parameter satisfies the water quality control parameter in the parameter determination unit, the natural environment water area is provided by the flow path switching valve provided downstream of the index measuring device. While stopping the discharge to the drainage flow path, the sewage that has been purified by the attached purification facility is delivered to a sewage purification facility operated by a wide area coalition in which the municipality using the water supply facility or a neighboring municipality cooperates. Sewage purification system, which is fed to the public sewage flow path from the flow path switching valve or circulated from the flow path switching valve to the attached purification facility.

Images