Operating method of incineration facility and incineration facility

Abstract

This invention provides an operating method for an incineration facility that can be effectively used as an evacuation center during disasters and that can properly treat domestic wastewater. [Solution] A method for operating an incineration facility that includes a wastewater closed system including a regeneration treatment facility that regenerates plant wastewater and domestic wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, and processes waste received by the incineration facility in an incinerator, wherein when the incinerator is stopped or in a state of preparation for stopping operation, the destination of the treated water discharged from the purification facility that is included in the regeneration treatment facility and treats the domestic wastewater is switched from the circulation path of the wastewater closed system to a wastewater path that discharges to the outside of the incineration facility.

Description

Technical Field

[0001] The present invention relates to an operation method of an incineration facility and an incineration facility.

Background Art

[0002] [[ID=ll]] In recent years, waste treatment facilities such as garbage incineration facilities are expected to play roles such as self - contained and decentralized power supply and heat supply, and as disaster prevention bases in the region by ensuring operation even during large - scale disasters through ensuring strengthening such as seismic resistance improvement, ground improvement, and flood countermeasures of the facilities.

[0003] In addition, in order to obtain understanding from local residents regarding the incineration facility, an environmental protection - oriented drainage closed - system is being considered, in which the drainage generated in the facility is treated and reused as exhaust gas cooling water or the like to avoid discharging the drainage into sewer or public water areas. The drainage closed - system may target only plant drainage or may target domestic drainage generated in the facility in addition to plant drainage. When domestic drainage is included, it is sometimes called a complete drainage closed - system.

[0004] Patent Document 1 discloses a drainage treatment method for efficiently purifying both inorganic drainage and organic drainage. Specifically, the drainage treatment method in the garbage incineration treatment facility includes a first step of adding a chemical agent composed of an alkali agent, a flocculant, and a flocculation aid to the inorganic drainage to insolubilize heavy metals as hydroxides and aggregate suspended substances; a second step of sedimentation - separating the hydroxide of heavy metals and the aggregate of suspended substances; a third step of neutralizing the supernatant drainage in the second step; a fourth step of mixing organic drainage containing organic substances into the supernatant drainage neutralized in the third step; and a fifth step of biologically treating and decomposing the organic substances in the mixed drainage.

[0005] The treated water treated by the drainage treatment method described in Patent Document 1 is reused within the facility or discharged outside the facility.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Application Publication No. 10-99898 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Incineration facilities are expected to play a role as regional disaster prevention bases, and their use as evacuation shelters for local residents in the event of a disaster is being considered in particular. Incineration facilities equipped with power generation equipment have the advantage of ensuring power supply on-site as long as the incinerator is operating, even if commercial power is lost. Even if the incinerator is temporarily shut down, it can be restarted by activating an emergency generator.

[0008] Incidentally, in incineration facilities that do not employ a closed drainage system, wastewater generated within the facility must be discharged into the sewage system. If the sewage system is damaged during a disaster, there will be nowhere to discharge the wastewater, leading to the problem of toilets becoming unusable.

[0009] In incineration facilities employing a closed-loop wastewater system, wastewater generated within the facility is treated by a purification system. As long as the power supply is not lost, the electrical loads such as aeration devices and pumps in the purification system can be driven. However, if the incinerator stops due to running out of waste, the treated water from the purification system cannot be consumed within the facility, and eventually the toilets become unusable. Furthermore, if the incinerator stops, power generation by the power generation equipment also stops. Therefore, if the commercial power supply is lost, there is a problem in that the fuel costs required to operate emergency generators in order to secure the necessary power within the incineration facility increase.

[0010] The objective of the present invention is to provide an incineration facility and a method for operating an incineration facility that can be effectively used as an evacuation center in the event of a disaster and that can properly treat domestic wastewater. [Means for solving the problem]

[0011] To achieve the above objectives, the first characteristic configuration of the incineration facility operation method according to the present invention is an incineration facility operation method that includes a wastewater closed system including a regeneration treatment facility that regenerates plant wastewater and domestic wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, and processes waste received into the incineration facility in an incinerator, wherein when the incinerator is stopped or in a state of preparation for stopping operation, the destination of the treated water discharged from the purification facility that is included in the regeneration treatment facility and treats the domestic wastewater is switched from the circulation path of the wastewater closed system to a wastewater path that discharges to the outside of the incineration facility.

[0012] When an incinerator is shut down or preparing to shut down, the treated water discharged from the purification equipment in the closed drainage system cannot be used as process water for the incineration plant, and the use of toilets and other sources of domestic wastewater is restricted. In such cases, by switching from the circulation route of the closed drainage system, which circulates and supplies treated water as process water, to a drainage route that discharges the water outside the facility, the toilets and other facilities can be used continuously. For example, before a disaster occurs, consuming the treated water as process water for the incineration plant allows for operation of the incineration plant with sufficient consideration for environmental protection, and after a disaster, by discharging the purified treated water into public water bodies via the drainage route, the facility can be effectively used as an evacuation center that can continuously tolerate the generation of domestic wastewater. It should be noted that the treated water discharged from the purification equipment maintains a certain level of water quality to prevent environmental degradation.

[0013] The second characteristic configuration is a wastewater closed system that includes a regeneration treatment facility that regenerates plant wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, and an incineration facility operation method that processes waste received into the incineration facility in an incinerator, wherein the incineration facility is equipped with a switchable first drainage route that discharges domestic wastewater generated in the incineration facility to the sewer system and a second drainage route that discharges domestic wastewater generated in the incineration facility into a public water body after being treated by a purification facility, and the destination of the domestic wastewater generated in the incineration facility is switched from the first drainage route to the second drainage route when the sewer system becomes unusable, the incinerator stops operating, or the facility is in a state of preparation for shutdown as it approaches the shutdown of operation.

[0014] In an incineration facility equipped with a closed wastewater system that includes a recycling treatment facility for reusing wastewater other than domestic wastewater as process water in the incineration facility, before a disaster occurs and the sewage system is functioning normally, domestic wastewater generated at the facility can be discharged into the sewer system via a first drainage route, allowing for the continued use of domestic wastewater sources such as toilets. However, if the sewage system is damaged due to a disaster, it becomes difficult to use domestic wastewater sources such as toilets. Even in such cases, the facility is equipped with a second drainage route that biologically treats domestic wastewater with a purification system and discharges the treated water from the purification system into a public water body. When the incinerator is stopped or preparing to shut down, the drainage route can be switched from the first to the second, allowing for the continued use of domestic wastewater sources such as toilets, and enabling the facility to be effectively utilized as an evacuation center that can continuously tolerate the generation of domestic wastewater.

[0015] The third characteristic configuration is that, in addition to the first or second characteristic configuration described above, the incineration facility is equipped with a steam power generation system that generates electricity using steam produced by the heat of incineration of waste generated in the incinerator, and supplies the electricity generated by the steam power generation system to the purification equipment.

[0016] In incinerators equipped with steam power generation equipment, the electricity generated by the steam power generation equipment can be supplied to the purification equipment, allowing for the continued use of wastewater sources such as toilets even if commercial power is lost.

[0017] The fourth characteristic configuration, in addition to the third characteristic configuration described above, is that when the incinerator is stopped or in a state of preparation for shutdown, the power supply to the purification equipment is switched from the steam power generation equipment to commercial power or emergency power.

[0018] Because the shutdown of the incinerator makes it difficult to supply power from the steam power generation equipment to the wastewater treatment equipment, when the incinerator is shut down or preparing to shut down, the power supply to the wastewater treatment equipment is switched to commercial power or emergency power, allowing for the continued use of wastewater sources such as toilets.

[0019] The fifth characteristic configuration is that, in addition to the first or second characteristic configuration described above, the incineration facility is equipped with energy recycling equipment, including a biogas power generation facility or a solar power generation facility, which generates electricity from biogas obtained by methane fermentation treatment of the accepted waste, and supplies the electricity generated by the energy recycling facility to the purification facility.

[0020] By supplying power to the wastewater treatment equipment from energy recovery equipment, including biogas power generation equipment or solar power generation equipment installed at the facility, it is possible to continue using sources of domestic wastewater, such as toilets, even when the incinerator is shut down and it is difficult to supply power from the steam power generation equipment.

[0021] The sixth characteristic configuration, in addition to the first or second characteristic configuration described above, is that it determines whether the incinerator is in the state of preparation for shutdown based on at least one of the following: the amount of waste fed into the incinerator, the amount of waste stored, the amount of chemicals and fuel stored, the amount of plant water stored, the amount of combustion air supplied, the amount of steam generated by a waste heat boiler that generates steam using the heat from incinerating the waste, the amount of electricity generated by a steam power generation facility that generates electricity using the steam supplied from the waste heat boiler, and the water level in the boiler feedwater tank.

[0022] When any one of the following is detected: a decrease in the input amount of waste, a decrease in the storage amount of waste, a decrease in the storage amount of chemicals / fuels, the storage amount of plant water, a decrease in the supply amount of combustion air, a decrease in the amount of steam generated by the waste heat boiler, a decrease in the power generation amount of the steam power generation facility, or an increase in the water level of the boiler feed water tank, it can be determined that the incineration target has disappeared or that there is no utility for incineration processing, and the furnace has reached a stop state. Whether it is in a state of preparation for operation stop can be determined based on whether at least any one of them becomes a value indicating a decrease in the incineration target leading to the stop of the furnace.

[0023] In addition to the first or second characteristic configuration described above, the seventh characteristic configuration is that when the automatic control device for automatically operating the incinerator executes automatic stop control for automatically stopping the incinerator, it determines whether the incinerator is in the state of preparation for operation stop.

[0024] When the automatic control device of the incinerator executes automatic stop control, it can be determined that it is in a state of preparation for operation stop. For example, when the automatic control device determines, according to a predetermined determination algorithm, that the operation of the incinerator cannot be continued due to a decrease in the incineration target or a failure of equipment, or when it determines that a large earthquake has occurred based on the input value from the seismometer and the operation of the incinerator is dangerous, etc., it is programmed to execute an automatic stop algorithm. When such an automatic stop algorithm is executed, it can be determined that the incinerator is in a state of preparation for operation stop. For example, an algorithm for issuing an alarm when the automatic stop algorithm is executed may be incorporated.

[0025] The first characteristic configuration of the incineration facility according to the present invention is an incineration facility provided with a drainage closed system including a regeneration treatment facility for regenerating and reusing plant drainage and domestic sewage generated by the operation of the incineration facility as process water of the incineration facility, comprising an incinerator for incinerating received waste, a purification facility for treating the domestic sewage, a switching means for switching the destination of the treated water discharged from the purification facility between a circulation path of the drainage closed system and a drainage path for discharging to the outside of the incineration facility, and a signal output means for outputting a switching signal to the switching means based on at least one value of the input amount of waste to the incinerator, the storage amount of waste, the storage amount of chemicals and fuel, the storage amount of plant water, the supply amount of combustion air, the amount of steam generated by a waste heat boiler for generating steam with the incineration heat of the waste, the power generation amount of a steam power generation facility for generating power with the supply steam from the waste heat boiler, and the water level of the boiler feed water tank.

[0026] The second characteristic configuration is an incineration facility provided with a drainage closed system including a regeneration treatment facility for regenerating and reusing plant drainage and domestic sewage generated by the operation of the incineration facility as process water of the incineration facility, comprising an incinerator for incinerating received waste, a switching means for switching the destination of the domestic sewage between a first drainage path for discharging to a sewer and a second drainage path for discharging to a public water area after treatment by a purification facility, and a signal output means for outputting a switching signal to the switching means based on at least one value of the input amount of waste to the incinerator, the storage amount of waste, the storage amount of chemicals and fuel, the storage amount of plant water, the supply amount of combustion air, the amount of steam generated by a waste heat boiler for generating steam with the incineration heat of the waste, the power generation amount of a steam power generation facility for generating power with the supply steam from the waste heat boiler, and the water level of the boiler feed water tank.

Effect of the Invention

[0027] As described above, according to the present invention, it has become possible to provide an operation method of an incineration facility that can be effectively utilized as an evacuation site in the event of a disaster and can appropriately treat domestic sewage, and an incineration facility.

Brief Description of the Drawings

[0028] [Figure 1] Diagram illustrating the first type of incineration facility [Figure 2] System diagram illustrating the normal operation of tap water and treated water used in the incineration facility. [Figure 3] System diagram illustrating the use of tap water and treated water in incineration facilities during disasters. [Figure 4] (a) is a flowchart explaining the switching of the drainage route, and (b) is a flowchart explaining the switching of the power supply system. [Figure 5] Diagram illustrating the second type of incineration facility. [Figure 6] System diagram illustrating the normal operation of tap water and treated water used in the incineration facility. [Figure 7] System diagram illustrating the use of tap water and treated water in incineration facilities during disasters. [Modes for carrying out the invention]

[0029] The incineration facility and the method of operating the incineration facility according to the present invention are described below.

[0030] [Diagram illustrating the incineration facility in the first embodiment] Figure 1 shows an incineration facility according to a first embodiment to which the present invention is applied. The incineration facility comprises an incinerator and its surrounding equipment for incinerating accumulated combustible waste, a solubilization tank for solubilizing food waste, and a methane fermentation tank and its surrounding equipment for methane fermentation of the solubilized organic acids.

[0031] This section describes the incinerator and its surrounding equipment. Garbage collected from general households and other sources is placed in a garbage pit, stored, and agitated before being fed from the garbage pit to the garbage hopper of the incinerator by a garbage crane. Combustible waste, bulky waste crushed by a crusher, and unsuitable materials for fermentation separated from food waste by a sorting device are accumulated in the garbage pit. A stoker-type incinerator is installed, and the garbage placed in the garbage hopper is fed into the combustion chamber by a pusher, and is incinerated while being agitated and transported by the stoker mechanism.

[0032] In the freeboard section, which is the space above the combustion chamber, the combustion gases are completely burned, and the exhaust gas that flows down into the flue is purified by exhaust gas treatment equipment before being exhausted through the chimney via an induced draft fan. Electricity is generated by a steam power generation system equipped with a steam turbine driven by steam generated by a waste heat boiler with water tubes arranged in the side wall of the freeboard section and superheated by a superheater, and this generated electricity is configured to supply power to various equipment installed in the incineration facility.

[0033] Along the flue are various exhaust gas treatment devices, including an air preheater to recover waste heat, a cooling tower that sprays water into the exhaust gas to lower its temperature, a neutralizing agent supply device to neutralize acidic gas components, and a dust collector to collect fly ash and other debris.

[0034] The proteins, carbohydrates, and lipids that make up the food waste sorted by the sorting device are hydrolyzed in a solubilization tank, for example, to break down into amino acids, sugars, and long-chain fatty acids. After solubilization, which generates organic acids such as acetic acid and butyric acid via intermediate products, the waste is subjected to methane fermentation by methane-producing bacteria in a methane fermentation tank.

[0035] The biogas produced in the methane fermentation tank is collected in a gas holder and used to generate electricity in a biogas power generation facility equipped with a gas turbine. The system is configured to supply power to various devices located in the incineration facility.

[0036] The digestate, which is produced through methane fermentation and stored in a digestate storage tank, is separated into solid and liquid components by a solid-liquid separator. The solid components are composted in a composting facility, and the liquid components are biologically treated in a septic tank or other purification facility. The treated water purified by the purification facility is used as process water in the incineration plant. Domestic wastewater from baths, toilets, and handwashing facilities installed in the incineration plant is also discharged into the purification facility for purification treatment.

[0037] Figure 2 shows the flow of tap water supplied to the incineration facility. The tap water supplied to the incineration facility is stored in fire extinguishing water tanks, domestic water tanks, plant water tanks, and equipment cooling water tanks. The water stored in the fire extinguishing water tanks is used for fire hydrants, roof sprinklers, and water cannons. The water stored in the domestic water tanks is used for various domestic purposes such as baths, flush toilets, and handwashing. The water stored in the plant water tanks is used for various plant purposes such as pure water systems for boiler water, catalyst-free denitrification systems, plant wastewater treatment equipment, and chemical spray systems. The water stored in the equipment cooling water tanks is used as cooling water for equipment such as steam turbine oil coolers, steam turbine generators, gland steam condensers, in-furnace monitoring ITVs, induced draft fans, exhaust gas circulation fans, boiler feedwater pumps, and air compressors.

[0038] Inorganic plant wastewater, such as blowdown water used for cooling equipment, floor cleaning water, and boiler drainage, is treated by the plant wastewater treatment facility with chemical additives for neutralization, coagulation, and sedimentation to become reusable water, which is then stored in a reuse tank. The water stored in the reuse tank is supplied to ammonia absorption tanks, fly ash treatment equipment, plant wastewater treatment facilities, wastewater treatment equipment, car wash equipment, floor cleaning water, cooling towers, and recycling facilities.

[0039] Domestic wastewater supplied from the domestic water tank and used for domestic purposes is discharged into a purification system. After biological treatment in the purification system, the treated water, along with a portion of the reused water, is stored in an injection tank as process water for the system. The purification system includes an aerobic tank and a solid-liquid separation tank, which purify organic wastewater by decomposing it with aerobic microorganisms supported on a carrier. The aerobic tank is equipped with electrical load devices such as an aeration device and a pump that discharges the treated water to the outside. The water stored in the injection tank is supplied to a cooling tower and used to cool the exhaust gas.

[0040] In other words, the incineration facility has a closed wastewater treatment system that includes a recycling treatment facility that recycles plant wastewater and domestic wastewater generated by the operation of the facility and reuses the recycled treated water as process water for the incineration facility. Process water refers to the water used from the storage in the aforementioned reuse tank and injection tank, and the recycling treatment facility refers to the plant wastewater treatment facility and purification facility mentioned above.

[0041] The incineration facility is equipped with commercial power receiving equipment and, in addition to the steam power generation equipment and biogas power generation equipment mentioned above, also has solar power generation equipment and emergency power generation equipment. When starting up the incinerator and methane fermentation tanks, power is supplied to each electrical load from the commercial power supply. After the incinerator and methane fermentation tanks are started up, once the power generated by the steam power generation equipment and biogas power generation equipment reaches a sufficient capacity, a power control device is installed that switches the power supply to each electrical load of the incineration facility from the commercial power supply to the internal power supply of the steam power generation equipment and biogas power generation equipment. The power control device is configured to control the reverse power flow to the commercial power supply when the power generated by the steam power generation equipment, biogas power generation equipment and solar power generation equipment, individually or combined, can secure a capacity that can be supplied externally. The emergency power generation equipment is equipped with an emergency generator as an emergency power source and is operated in emergencies such as when the commercial power supply is lost.

[0042] Such incineration facilities are expected to serve as regional disaster prevention centers, and are particularly anticipated to be used as evacuation shelters for local residents in the event of a disaster. Incineration facilities equipped with steam power generation equipment have the advantage of ensuring power on-site as long as the incinerator is operating, even if commercial power is lost. Even if the incinerator temporarily stops, it is possible to start the incinerator by activating an emergency generator, and then secure power on-site by generating electricity with the steam power generation equipment.

[0043] However, if the waste pit runs out of stored waste, or if the stock of chemicals necessary for operating the incinerator runs out, it becomes difficult to continue operating the incinerator, and it must be shut down. If the incinerator is shut down, there is no use for the treated water from the purification system, and if the water tank that stores the treated water becomes full, it becomes difficult to continue operating the purification system. If the purification system cannot be operated in a facility that is accommodating many residents as an evacuation center, it becomes impossible to treat domestic wastewater, and an extremely important problem arises: toilets and other facilities become unusable.

[0044] This incineration facility is designed to prevent such situations from occurring. When the incinerator is shut down or in a state of preparation for shutdown, the treated water discharged from the purification equipment, which is included in the regeneration treatment facility and biologically treats domestic wastewater, is circulated and supplied to the closed wastewater system. In other words, as shown in Figure 3 in the example of Figure 2, the wastewater route is switched from the wastewater route from the purification equipment to the injection tank to the wastewater route that discharges outside the facility, i.e., to a public water body.

[0045] While maintaining a closed wastewater system under normal circumstances, if it becomes necessary to shut down the incinerator due to a disaster, the system can be switched from a circulation route that recirculates treated water as process water to a wastewater route that discharges it outside the facility, allowing for the continued use of toilets and other facilities. The treated water discharged from the purification equipment is disinfected in disinfection tanks and other facilities to ensure a certain level of water quality that does not degrade the environment. In principle, the water is treated to meet the discharge standards for public water bodies.

[0046] Specifically, the wastewater treatment plant's drainage pipes are connected to a liquid supply pipe that circulates and supplies wastewater to a closed wastewater system (injection tank), and an external drainage pipe that discharges wastewater into a public water body such as a river flowing outside the incineration facility. These connections are made switchable via a switching valve such as a three-way valve, which functions as a switching mechanism. When the incinerator stops operating or approaches a shutdown state, the administrator can switch the switching valve to achieve this.

[0047] Instead of the administrator manually switching the switching valve, a route switching device may be provided that includes an electronic control circuit that automatically detects when the incinerator has stopped operating or is approaching a shutdown state and outputs a switching signal to automatically switch the switching valve. The route switching device functions as a signal output means that outputs a switching signal to the switching means described above.

[0048] As shown in Figure 1, the incineration facility is equipped with an automatic control system consisting of a computer that automatically controls the incinerator. The automatic control system receives detection values ​​from various sensors installed in the incinerator and controls the incinerator by outputting drive signals to various actuators based on those values.

[0049] Under normal circumstances, the automatic control device executes an automatic control algorithm that automatically controls the amount of waste fed into the furnace, the waste transport speed by the stoker mechanism, the amount of air for primary combustion, and the amount of air for secondary combustion, based on values ​​detected by various sensors, such as the combustion temperature of the incinerator, the oxygen concentration of the exhaust gas, and the amount of steam generated by the waste heat boiler.

[0050] In the event of a disaster such as an earthquake, the incinerator will be automatically shut down if deemed necessary for safety based on seismometer readings. Even if the incinerator continues to operate without automatic shutdown control during a disaster, if a predetermined judgment algorithm subsequently determines that the incinerator cannot continue operating due to a decrease in the amount of material to be incinerated or equipment failure, the system will transition to a shutdown preparation state and execute the automatic shutdown algorithm.

[0051] Besides earthquake detection, the main reasons that lead to the incinerator being shut down and unable to continue operation include malfunctions in the induced draft fan, malfunctions in the boiler feedwater pump, abnormally high exhaust gas temperature at the dust collector inlet, abnormally low boiler steam cylinder temperature, and manual operation of the emergency stop button.

[0052] The route switching device is configured to automatically control the switching valve that switches the destination of the treated water discharged, as described above, when it receives a signal from the incinerator's automatic control device indicating that it has entered a state of preparation for shutdown in the event of a disaster. If the device is configured to issue an alarm along with a signal indicating that the automatic shutdown algorithm has been executed, the administrator may switch the switching valve after confirming the alarm or after making a comprehensive judgment on the facility's operating status.

[0053] The automatic control device can be configured to include a determination algorithm that determines whether at least one of the following exceeds a predetermined threshold: the amount of waste fed into the incinerator, the amount of waste stored, the amount of chemicals and fuel stored, the amount of plant water stored, the amount of combustion air supplied, the amount of steam generated by a waste heat boiler that generates steam using the heat from incinerating waste, the amount of electricity generated by a steam power generation facility that generates electricity using the steam supplied from the waste heat boiler, or the boiler feedwater tank water level. The device can be configured to transition to a shutdown preparation state when the predetermined threshold is exceeded.

[0054] Furthermore, the system may be configured to output a signal to the automatic switching control device when the administrator recognizes that any one of the following, displayed on a monitor in the central control room of the incinerator, exceeds a predetermined threshold: the amount of waste fed into the incinerator, the amount of waste stored, the amount of chemicals and fuel stored, the amount of plant water stored, the amount of combustion air supplied, the amount of steam generated by the waste heat boiler that generates steam using the heat from incinerating waste, the amount of electricity generated by the steam power generation equipment that generates electricity using the steam supplied from the waste heat boiler, or the water level in the boiler feedwater tank.

[0055] Figure 4(a) shows a flowchart of an example of drainage route switching control by a route switching device. The route switching device monitors the operating status of the incinerator by the automatic control device of the incinerator described above (SA1), and when it determines that the incinerator is stopped or has transitioned to a state of preparing to stop operation (SA2), it switches the switching valve from the liquid supply pipe to the external drainage pipe so that the purification equipment can continue to operate (SA3). If the incinerator is in operation, it switches the switching valve from the external drainage pipe to the liquid supply pipe to maintain a closed drainage system (SA4).

[0056] In the example described above, the incineration facility is equipped with internal power generation equipment, including steam power generation equipment, biogas power generation equipment, solar power generation equipment, and emergency power generation equipment, in addition to commercial power receiving equipment. It is further equipped with a power system switching device that has a distribution board to control which power is supplied to which electrical load. The power system switching device is configured to supply power from the commercial power receiving equipment to the various electrical loads installed in the incinerator when the incinerator is started up, and then switch to supplying power from the steam power generation equipment, which is part of the internal power generation equipment, once the incinerator is started up. Furthermore, it is configured to control the sale of electricity by reverse power flowing back to the commercial power source when the power generated by the steam power generation equipment, biogas power generation equipment, and solar power generation equipment reaches a sufficient capacity.

[0057] The power system switching device is configured to ensure that even if commercial power is lost, sources of domestic wastewater such as toilets can continue to be used, by supplying power generated by the steam power generation equipment to at least the wastewater treatment equipment in the event of a disaster when commercial power is lost and the incinerator continues to operate.

[0058] Furthermore, when the incinerator is stopped or in a state of preparation for shutdown, it becomes difficult to supply power from the steam power generation equipment to the purification equipment. Therefore, the power supply system switching device switches at least the power supplied to the purification equipment from the steam power generation equipment to power supplied from other power generation equipment. If commercial power is restored, power is supplied from commercial power. If commercial power is lost, power is switched to energy regeneration equipment (renewable power supply equipment), including biogas power generation equipment or solar power generation equipment. If power supply from energy regeneration equipment is difficult, power is switched to emergency power supply equipment.

[0059] Figure 4(b) shows a flowchart of an example of power supply system switching control by a power supply system switching device. The power supply system switching device monitors the status of the commercial power supply and the internal power generation equipment (SB1), and if it is possible to supply power from the commercial power supply (SB2) and also possible to supply power from the steam power generation equipment or the regenerative power generation equipment (SB3, Y), it switches the power supply system to the electrical load devices of the incineration facility and the purification equipment to power supply from the steam power generation equipment or the regenerative power generation equipment (SB4). In this embodiment, in addition to the steam power generation equipment, there are multiple systems of biogas power generation equipment and solar power generation equipment as regenerative power generation equipment, so the power distribution to each electrical load device is controlled in advance, taking into account the respective power generation capacity and power generation time.

[0060] If power can be supplied from the commercial power source (SB2), and sufficient power cannot be supplied from the steam power generation equipment or the regenerative power source equipment (SB3,N), the power supply system to the electrical load devices of the incineration facility and the purification equipment will be switched to power from the commercial power source (SB5).

[0061] Furthermore, if commercial power is lost but steam power generation equipment or regenerative power generation equipment is sufficient (SB6, Y), the power supply system to the electrical load devices of the incineration and purification facilities will be switched to power from the steam power generation equipment or regenerative power generation equipment (SB7). If commercial power, steam power generation equipment, and regenerative power generation equipment are all lost (SB6, N), emergency generators will be started and the power supply system will be switched to power from the emergency power generation equipment (SB8). If the facility is being used as an evacuation center, considering the fuel consumption of the emergency power supply, power will be supplied to the minimum number of electrical load devices such as purification equipment, lighting, and air conditioners, thereby improving the living environment for evacuees.

[0062] [Diagram illustrating the second type of incineration facility] Figures 5 to 7 show an incineration facility according to a second embodiment to which the present invention is applied. In the following, the same configuration as the incineration facility of the first embodiment described above will not be explained, and only the differences will be described in detail. In the incineration facility of the second embodiment, under normal circumstances, domestic wastewater and digestate separated into solid and liquid by a solid-liquid separator are discharged into a sewer system extending from the facility, and in case of emergency, purification equipment such as a septic tank is available to operate.

[0063] The second type of incineration facility includes a closed wastewater system that includes a recycling treatment facility for recycling plant wastewater generated by the operation of the facility, excluding domestic wastewater, and reusing it as process water for the incineration facility. Furthermore, it includes a first wastewater route for discharging domestic wastewater generated at the facility into the sewer system, and a second wastewater route that includes a purification facility for biologically treating the domestic wastewater generated at the facility, and for discharging the treated water discharged from the purification facility into a public water body after the domestic wastewater has been biologically treated by the purification facility.

[0064] In the second embodiment of the incineration facility's operating method, the system is configured to switch from the first drainage route to the second drainage route when the sewer is unusable due to damage or other reasons, the incinerator is stopped, or is in a state of preparation for shutdown as it approaches shutdown.

[0065] In an incineration facility equipped with a closed wastewater system, such as the second type of incineration facility, which includes a recycling treatment facility that recycles plant wastewater other than domestic wastewater and reuses it as process water in the incineration facility, domestic wastewater generated at the facility can be discharged into the sewer system via the first drainage route before a disaster occurs when the sewer system is operating normally, allowing for the continued use of domestic wastewater sources such as toilets. However, if the sewer system is damaged due to a disaster, it becomes difficult to use domestic wastewater sources such as toilets. Even in such cases, by switching to a second drainage route in which domestic wastewater is biologically treated by a purification facility and the treated water discharged from the purification facility is discharged into a public water body, domestic wastewater sources such as toilets can be continued to be used, and the facility can be effectively utilized as an evacuation center that can continuously tolerate the generation of domestic wastewater.

[0066] Similar to the incineration facility described in the first embodiment, it is equipped with an automatic control device for the incinerator, a route switching device for treated water, and a power system switching device. As shown in Figure 6, under normal circumstances, the first switching valve is operated so that domestic wastewater and digestate after methane fermentation are treated in a septic tank or similar facility as needed to meet sewer discharge standards, and then discharged into the sewer system via sewer drainage pipes. As shown in Figure 7, the route switching device monitors the operating status of the incinerator by the automatic control device of the incinerator. When the incinerator stops operating in the event of a disaster, or when it is in a state of preparation for shutdown, there is a risk of damage to the sewage system. Therefore, the device operates the first switching valve installed in the sewer drain pipe to switch from discharge to the sewer to discharge to the purification system. At this time, it is preferable that the route switching device outputs a power supply control signal to the power system switching device so that power is supplied to the electrical load device of the purification system. Treated water flowing out of the purification drain pipe is discharged into the public water body via an external drain pipe.

[0067] Even if an incinerator that was stopped during a disaster is restarted, it is preferable to continue operating the wastewater treatment equipment if the sewer system is damaged. For this reason, it is preferable to install a second switching valve in the wastewater treatment pipe, as shown by the dashed line in Figure 7. The route switching device is preferably configured such that, after the first switching valve is switched to start the wastewater treatment equipment, when the incinerator is restarted, the second switching valve is switched to discharge the treated water from the wastewater treatment pipe to the liquid supply pipe that discharges to the injection tank, so that the treated water can be used as process water.

[0068] In the first and second embodiments, it is preferable to add a disaster occurrence signal to the status signal output by the automatic control device of the incinerator to the route switching device, which indicates that the incinerator is stopped or in a state of preparation for shutdown, to determine whether or not a disaster has occurred. By adding a disaster occurrence signal to the status signal, when the incinerator is started up afterward, the route switching device can determine whether or not a disaster is occurring, and the first and / or second switching valves can be controlled appropriately.

[0069] In the first and second embodiments, examples were described in which biogas power generation equipment and solar power generation equipment were provided as energy regeneration equipment. However, the energy regeneration equipment may also be wind power generation equipment, solar thermal power generation equipment, or other equipment that utilizes natural energy, and it is sufficient that it is equipped with power generation equipment other than steam power generation equipment.

[0070] In the first and second embodiments, a stoker-type incinerator was described as an example, but any type of incinerator may be used.

[0071] In the first and second embodiments, examples equipped with a biogas power generation facility were described, but the incineration facility may not be equipped with a biogas power generation facility.

[0072] In the first and second embodiments, biological treatment was described as an example of wastewater treatment equipment, but any treatment equipment that can produce water of a quality suitable for use or discharge is acceptable, such as treatment using membranes.

[0073] In the first embodiment, the drainage route was described as being switched to a public water body, but if a sewer system is available, the drainage route may be the sewer system.

[0074] It should be noted that the embodiments described above are merely examples of the present invention, and the specific configuration of each part can be appropriately modified and designed within the scope of achieving the effects of the present invention.

Claims

1. An incineration facility operation method comprising a wastewater closed system including a regeneration treatment facility that regenerates plant wastewater and domestic wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, wherein waste received by the incineration facility is treated in an incinerator, When the incinerator is stopped, or in a state of preparation for shutdown, A method for operating an incineration facility, characterized by switching the destination of treated water discharged from the wastewater treatment equipment included in the recycling treatment equipment for treating the domestic wastewater from the circulation path of the closed wastewater system to a wastewater path that discharges the water outside the incineration facility.

2. A method for operating an incineration facility, comprising a wastewater closed system including a regeneration treatment facility that regenerates plant wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, and processing waste received by the incineration facility in an incinerator, A first drainage route for discharging domestic wastewater generated at the aforementioned incineration facility into the sewer system, A second drainage route for discharging domestic wastewater generated at the aforementioned incineration facility into a public water body after it has been treated with a purification system, It is equipped with a switchable function. When the sewer system becomes unusable, the incinerator stops operating, or the incinerator is in a state of preparation for shutdown, A method for operating an incineration facility, characterized by switching the destination of domestic wastewater generated at the incineration facility from the first drainage route to the second drainage route.

3. The method for operating an incineration facility according to claim 1 or 2, wherein the incineration facility is equipped with a steam power generation facility that generates electricity using steam generated by the heat of incineration of waste produced in the incinerator, and the electricity generated by the steam power generation facility is supplied to the purification facility.

4. The method for operating an incineration facility according to claim 3, wherein when the incinerator is in a stopped state, or in a state of preparation for shutdown, the power supplied to the purification equipment is switched from the steam power generation equipment to commercial power or emergency power.

5. The method for operating an incineration facility according to claim 1 or 2, wherein the incineration facility is equipped with energy regeneration equipment including a biogas power generation facility or a solar power generation facility that generates electricity from biogas obtained by methane fermentation treatment of the accepted waste, and the electricity generated by the energy regeneration facility is supplied to the purification facility.

6. A method for operating an incineration facility according to claim 1 or 2, wherein the incinerator is in the state of preparation for shutdown based on at least one of the following: the amount of waste fed into the incinerator, the amount of waste stored, the amount of chemicals and fuel stored, the amount of plant water stored, the amount of combustion air supplied, the amount of steam generated by a waste heat boiler that generates steam using the heat from the incineration of waste, the amount of electricity generated by a steam power generation facility that generates electricity using the steam supplied from the waste heat boiler, and the water level in the boiler feedwater tank.

7. The method for operating an incineration facility according to claim 1 or 2, wherein an automatic control device for automatically operating the incinerator performs an automatic stop control for automatically stopping the incinerator, and determines whether or not the incinerator is in the state of preparation for stopping operation.

8. An incineration facility equipped with a closed wastewater system including a regeneration treatment facility that regenerates plant wastewater and domestic wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, An incinerator that burns the accepted waste, A wastewater treatment facility for the aforementioned domestic wastewater, A switching means for switching the destination of treated water discharged from the aforementioned purification equipment between the circulation path of the wastewater closed system and the wastewater path that discharges the water outside the incineration facility, A signal output means that outputs a switching signal to the switching means based on at least one of the following values: the amount of waste fed into the incinerator, the amount of waste stored, the amount of chemicals and fuel stored, the amount of plant water stored, the amount of combustion air supplied, the amount of steam generated by a waste heat boiler that generates steam using the heat from the incineration of waste, the amount of electricity generated by a steam power generation facility that generates electricity using the steam supplied from the waste heat boiler, and the water level in the boiler feedwater tank. An incineration facility equipped with [the necessary equipment / features].

9. An incineration facility equipped with a closed wastewater system including a regeneration treatment facility that regenerates plant wastewater and domestic wastewater generated by the operation of the incineration facility and reuses it as process water for the incineration facility, An incinerator that burns the accepted waste, A switching means for switching the destination of the aforementioned domestic wastewater between a first drainage route that discharges it into the sewer system and a second drainage route that treats it in a septic tank before discharging it into a public water body, A signal output means that outputs a switching signal to the switching means based on at least one of the following values: the amount of waste fed into the incinerator, the amount of waste stored, the amount of chemicals and fuel stored, the amount of plant water stored, the amount of combustion air supplied, the amount of steam generated by a waste heat boiler that generates steam using the heat from the incineration of waste, the amount of electricity generated by a steam power generation facility that generates electricity using the steam supplied from the waste heat boiler, and the water level in the boiler feedwater tank. An incineration facility equipped with [the necessary equipment / features].

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