JP2001062437A - Waste incineration system and waste incineration process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste incineration system which enables the design of a small-scale waste incineration equipment capable of performing incineration treatment of mixed waste, within the facilities, reduction of the amount of harmful substances in an incineration residue and an incineration flue gas, each formed in the waste incineration, and also effective utilization of waste heat. SOLUTION: The incineration process using this system comprises: subjecting mixed waste having various properties to pyrolysis in a pyrolysis equipment (incinerator) 1 having a heating region in an atmosphere having a low oxygen concentration or atmosphere containing no oxygen, to form a pyrolysis gas; introducing the pyrolysis gas into a reformer 4 for reforming the pyrolysis gas from the incinerator (pyrolysis equipment) 1 into a comparatively high grade fuel gas by using high temperature steam; combusting the fuel gas in a steam heater 10 for heating steam to a >=700 deg.C high temperature, to convert low temperature steam into high temperature steam and to continuously supply the high temperature steam to the reformer 4; and introducing a part of the high temperature steam or fuel gas into a secondary pyrolysis equipment 2, to subject a pyrolysis residue formed in the pyrolysis equipment 1 to secondary pyrolysis by using the high temperature steam, or secondary combustion by using the fuel gas. Thus, harmful substances in the mixed waste can be destroyed, decomposed and removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste treatment system and a waste treatment method, and more particularly to a method for preventing the generation of dioxin accompanying incineration of mixed waste and the disposal of incineration waste. The present invention relates to a waste treatment system and a waste treatment method for effectively utilizing thermal energy.

[0002]

2. Description of the Related Art Waste from medical facilities, various research facilities, food factories, large-scale accommodation facilities, large-scale eating and drinking facilities, etc. (hereinafter referred to as "medical facilities, etc.") includes biological materials, biological waste, synthetic resins, It contains various types of wastes such as fibrous materials, inorganic materials, metal materials, and organs of animals and plants, and is difficult to separate easily for practical reasons and sanitary reasons. For example, medical facility waste not only includes various waste materials such as blood, living organs, drugs, synthetic resins, glass, and fibrous materials, but also includes biological contaminants after sterilization or sterilization. Therefore, it is extremely difficult to manually perform the sorting process.

[0003] In the case of incineration of such difficult-to-separate waste in which various kinds of waste materials are mixed (hereinafter referred to as "mixed waste"), various substances which are undesirable from the viewpoint of air pollution prevention,
For example, exhaust gas containing a relatively large amount of dioxin is likely to be generated, and considering environmental regulations in recent years, it is difficult to incinerate mixed waste easily depending on the incineration equipment in the facility. For this reason, many medical facilities, etc. outsource the disposal of mixed waste to waste treatment specialists before sorting, and the contractor transports them out of the facility and then incinerates them under strict control. ing.

[0004] Combustion exhaust gas generated during incineration of wastes contains a large amount of waste heat. As a measure to effectively use such waste heat, waste heat recovery technology for introducing high-temperature exhaust gas into a waste heat recovery facility such as a waste heat boiler and recovering it as heat energy or electric energy has been studied for many years. Was. This research on waste heat recovery technology is mainly aimed at large-scale waste incineration equipment, and as a large-scale combined power generation facility using thermal energy generated during waste incineration, research on its practical use is underway. It is still ongoing.

[0005]

However, mixed waste, especially in medical facilities, even if sterilized or sterilized, is not suitable for removal outside the facility and is a source of biological infection. In the sense of completely isolating the incineration from the outside world, complete incineration in a medical facility is essentially desirable for protecting the environment around the facility. In this case, the incineration equipment in the facility minimizes the total amount of flue gas generated during incineration and the content of air pollutants in the flue gas, and in particular reduces the emission of pollutants such as dioxins into the atmosphere. It is desired to exhibit combustion performance that can be prevented as much as possible.

Further, in a facility such as a food factory or a large-sized accommodation facility, when a method is adopted in which mixed waste is carried out of the facility and then incinerated, it is often necessary to temporarily store and transport the mixed waste. This is costly and labor-intensive, which means that the waste heat recoverable waste in the facility is taken out of the facility by further consuming the energy of the transportation means. It is desired to develop a small-scale waste incineration facility capable of effectively recovering waste heat generated during waste incineration in such a medium-scale facility or small-scale facility as energy in an easy-to-handle form, for example, electric energy. However, such equipment has not yet been developed.

The present inventors have now developed a gasification and melting furnace type incinerator for melting waste with high-temperature air as a technique for preventing the release of harmful substances into the atmosphere.
This technology relates to a waste melting furnace of a type in which waste is melted with high-temperature air of about 1000 ° C., and can provide a small and highly efficient waste treatment apparatus capable of suppressing emission of harmful substances. , As a very promising technology in the future. The present inventors have already developed a solidifying agent and a solidifying technique for solidifying incineration residues such as medical waste (see, for example, JP-A-7-3163). This type of solidifying agent solidifies the residue after incineration into a tangible residue mass to prevent the combustion ash or fly ash from scattering or dissipating, and facilitates the removal of the residue.

[0008] However, even if it relies on this kind of technology, mixed wastes from medical facilities and the like contain various kinds of waste materials such as solids, liquids and semi-solids. There are circumstances in which incineration facilities such as medical facilities that can be prevented cannot be easily designed.

Further, the flue gas generated by incineration of waste has waste heat that can be effectively used in the facility.
It is theoretically possible to design a cogeneration facility that generates electricity from waste heat of exhaust gas. Here, in order to effectively use the waste heat in the facility, it is necessary to efficiently convert the thermal energy held by the exhaust gas from the incinerator into energy that can be easily handled, such as fuel, electric power, or a heat medium. is there. However, a technology for enabling such waste heat recovery with a small-scale facility has not yet been developed, and this type of cogeneration facility has not been realized.

Thus, without emitting harmful substances,
It is desired to develop a simple and compact waste incineration system that incinerates mixed waste from medical facilities and the like and efficiently converts thermal energy of exhaust gas into energy such as fuel, electric power or heat medium.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to incinerate mixed waste such as medical facilities in the same facility, and to produce incineration residues and combustion generated during incineration. An object of the present invention is to provide a relatively small-scale waste incineration system and a waste incineration method capable of reducing the amount of harmful substances contained in exhaust gas.

The present invention also provides a waste incineration system and a waste incineration method for converting waste heat of combustion exhaust gas generated at the time of incineration of mixed waste into energy in a form which can be effectively used, thereby effectively utilizing waste heat. The purpose is to provide.

[0013]

The present inventor has conducted intensive studies to achieve the above object, and as a result, has obtained
As described above, preferably, by mixing high-temperature steam heated to an ultra-high temperature range of 800 ° C. or more with a pyrolysis gas, a steam reforming reaction of the pyrolysis gas occurs without depending on the action of a specific catalyst. Further, the present inventors have found that the present invention can be promoted, and have achieved the present invention based on such knowledge.

That is, according to the present invention, in a waste incineration system for incinerating mixed waste, a pyrolysis apparatus having a calcination zone in a low oxygen concentration or oxygen-free atmosphere, and a reaction zone for secondary pyrolysis of a decomposition residue. A second pyrolysis apparatus comprising: a reforming apparatus for reforming a pyrolysis gas of the pyrolysis apparatus;
There is provided a waste incineration system comprising a high-temperature steam generator for generating the high-temperature steam described above, wherein the high-temperature steam is introduced into the reformer and the secondary pyrolyzer.

The present invention also provides a waste incineration method for incinerating a mixed waste in which various wastes of various properties and properties are mixed, wherein the mixed waste is pyrolyzed to generate a pyrolysis gas, Reforming the pyrolysis gas into a fuel gas with the high-temperature steam of the fuel gas, generating the high-temperature steam using the combustion heat of the fuel gas as a heat source, and secondary pyrolyzing the decomposition residue of the waste with the high-temperature steam. Disclosed is a method for incineration of waste.

The high-temperature steam heated to a high-temperature range of 700 ° C. or more has sufficient sensible heat required for the progress of the reforming reaction,
The amount of heat required for the endothermic reforming reaction of the pyrolysis gas is supplied by the sensible heat of the high-temperature steam itself. The reformed gas of the pyrolysis gas is burned in the high-temperature steam generator, and the heat of combustion is consumed to generate high-temperature steam. Preferably, the waste incineration system generates relatively low temperature superheated steam by sensible heat held by the pyrolysis gas or reformed gas, and heats the low temperature steam by heat of combustion of the reformed gas,
The high temperature steam is generated. The high-temperature steam is supplied to the reformer, not only to reform the pyrolysis gas as described above, but also to the decomposition residue of the waste steamed in the sintering zone, and secondary pyrolyze the decomposition residue. As a result, harmful substances such as dioxin remaining in the decomposition residue are destroyed,
Decomposed and removed.

From another viewpoint, the present invention relates to a waste incineration system for incinerating mixed waste, which has a pyrolysis apparatus having a low oxygen concentration or oxygen-free atmosphere firing zone and a secondary combustion zone for decomposition residues. A secondary pyrolysis device, a reforming device for reforming a pyrolysis gas of the pyrolysis device, and a high-temperature steam generation device for generating high-temperature steam of 700 ° C. or more, wherein the high-temperature steam is A waste incineration system is provided, wherein the reformed gas from the reformer is introduced into the secondary combustion zone.

The present invention also relates to a waste incineration method for incinerating a mixed waste in which various kinds of properties and physical properties are mixed, wherein the mixed waste is pyrolyzed to generate a pyrolysis gas, Reforming the pyrolysis gas into a fuel gas with the high-temperature steam, generating the high-temperature steam using the combustion heat of the fuel gas as a heat source, and introducing the fuel gas into a secondary combustion zone of the decomposition residue of the waste. And a method of incinerating a waste, wherein the decomposition residue is subjected to secondary combustion.

As described above, the pyrolysis gas is reformed by a reforming reaction with high-temperature steam, and the reformed gas is supplied to a high-temperature steam generator and burned. The high-temperature steam generator generates the high-temperature steam by the combustion heat of the reformed gas. The reformed gas is introduced into the secondary combustion zone and initiates and maintains the reburning reaction of the cracked residue of the steamed waste in the firing zone. As a result, the decomposition residue is secondarily thermally decomposed, and harmful substances such as dioxin remaining in the decomposition residue are destroyed and decomposed and removed.

According to such a waste incineration system and a waste incineration method, mixed waste from a medical facility or the like is incinerated in the facility, and incineration residues generated during incineration and harmful substances contained in combustion exhaust gas are contained. The amount can be reduced. In addition, the waste incineration system having the above configuration can be designed to have a relatively small configuration that can be installed in the premises of a medical facility or the like.

[0021] Preferably, the waste incineration system having the above configuration further includes a power generator, and the power generator includes an internal combustion engine that operates using the reformed gas as fuel. More preferably, the waste incineration system further includes a heat exchange device through which the pyrolysis gas and / or the reformed gas can flow, and the heat exchange device heats the heat medium fluid by the sensible heat of the gas. I do. Preferably, the heating medium fluid after heating is low-temperature steam to be heated to the high-temperature steam or steam to be supplied to equipment outside the system.

According to such a configuration, the mixed waste in a medical facility or the like is incinerated in the facility, and
The waste heat of the flue gas generated during incineration is converted into energy in a form that can be used effectively. Such energy conversion enables the design of a cogeneration facility capable of efficiently and effectively using waste heat generated during waste incineration.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a preferred embodiment of the present invention, a waste incineration system pyrolyzes a mixed waste containing various types of solids, liquids, semi-solids, and other wastes to generate a pyrolysis gas. Is generated, and the pyrolysis gas is reformed into high-grade fuel gas by high-temperature steam. The fuel gas is supplied to a high-temperature steam generator and a power generator. The high-temperature steam generator is operated at a temperature of 700 ° C. or more,
The power generator generates steam in an ultra-high temperature range having a temperature of 0 ° C. or higher, and drives the generator to output electric power. The high-temperature steam of the high-temperature steam generator is used not only for reforming the pyrolysis gas as described above, but also for heat treatment of the decomposition residue of the mixed waste. The decomposition residue is secondarily thermally decomposed by the action of steam in an ultra-high temperature range, and harmful substances, especially dioxin, in the decomposition residue are destroyed and decomposed and removed.

FIG. 1 is a schematic block flow diagram showing the overall configuration of a waste incineration system according to such an embodiment. The waste incineration system consists of a pyrolysis unit with a low oxygen concentration or oxygen-free atmosphere firing zone, a secondary pyrolysis unit that decomposes the decomposition residue by secondary pyrolysis, and a pyrolysis gas from the incinerator. A high-temperature steam generator that generates ultra-high-temperature steam, a power generator that generates power using the reformed gas as a fuel for operation, and a solidification device that reduces and solidifies the residue after secondary pyrolysis. Prepare.

The mixed waste is put into the baking zone of the pyrolysis apparatus at a time, and is thermally decomposed by the steaming action of the baking zone. The decomposition residue of the mixed waste is introduced into the detoxification zone of the secondary pyrolysis unit. In the detoxification zone, the decomposition residue undergoes secondary thermal decomposition in the presence of high-temperature steam, and harmful substances in the decomposition residue are destroyed and thermally decomposed. The solidifying agent is supplied from the solidifying device to the detoxification zone, and the residue after the second thermal decomposition is reduced in volume by the solidifying agent and then carried out of the system.

The high-temperature pyrolysis gas generated in the pyrolyzer is introduced into the reformer, mixed with high-temperature steam, and subjected to a steam reforming reaction of hydrocarbons proceeding in the presence of the high-temperature steam. (Reformed gas). Part of the fuel gas is introduced into the high-temperature steam generator. A relatively low temperature superheated steam is supplied to the high temperature steam generator. The low-temperature steam is, for example, 200 ° C. to 300 ° C.
It has a temperature of about ° C. Preferably, a low-temperature steam generation device or a heat exchange device that generates low-temperature steam by the sensible heat of the reformed gas or the pyrolysis gas is interposed in the feed path of the reformed gas or the pyrolysis gas. The reformed gas undergoes a combustion reaction in the high-temperature steam generator, and the low-temperature steam receives the heat of combustion of the reformed gas and is heated to an ultra-high temperature range. Supplied.

A part of the reformed gas is supplied to a driving unit of the power generation device. The drive unit includes an internal combustion engine such as a gas turbine or a Stirling engine, and drives a generator of the power generator. The drive unit operates by the combustion reaction of the fuel gas,
The generator is driven, and the generator transmits electric power out of the system.

The waste incineration system thus configured generates fuel gas (reformed gas) and high-temperature steam using waste heat or heat energy in the system without depending on a heat source outside the system. In addition, harmful substances in the pyrolysis residue are removed using high-temperature steam, power is generated using fuel gas, and power is output outside the system. In addition, after the pyrolysis gas of the mixed waste undergoes the reforming reaction and the reburning reaction by the reformer and the high-temperature steam generator, the high-temperature steam generator outputs the exhaust gas containing no harmful substances and unburned components. It is discharged out of the system.

According to another preferred embodiment of the present invention, in the waste incineration system configured as described above, the reformed gas is used as a fuel for secondary combustion of the decomposition residue of the mixed waste.

FIG. 2 is a schematic block flow diagram showing the overall configuration of the waste incineration system according to such an embodiment. The waste incineration system shown in FIG. 2 converts a pyrolysis device having a low oxygen concentration or oxygen-free atmosphere firing zone, a secondary combustion device having a secondary combustion zone for decomposition residues, and a pyrolysis gas from an incinerator. Reformer, a heat exchanger that generates low-temperature steam by the sensible heat of the fuel gas (reformed gas), a high-temperature steam generator that generates steam in an ultra-high temperature range, and an operating reformed gas A power generator for generating power as fuel.

[0031] The mixed waste is put into the calcination zone of the pyrolysis apparatus at a time, and is thermally decomposed by the steaming action of the calcination zone. The decomposition residue of the mixed waste is introduced into the secondary combustion zone of the secondary combustion device. A part of the reformed gas is supplied to the secondary combustion zone, and the decomposition residue is reburned by the combustion reaction of the reformed gas. The harmful substances in the decomposition residue are destroyed by the reburning reaction and are thermally decomposed, and the residue after the secondary combustion is carried out of the system as general waste.

The high-temperature pyrolysis gas generated in the pyrolysis apparatus is introduced into the reforming apparatus, and is reformed into a high-quality fuel gas (reformed gas) as described above. Part of the fuel gas is introduced into a high-temperature steam generator,
Produces high temperature steam as described above. The high-temperature steam is supplied to the reformer to generate and maintain a steam reforming reaction of the reformer. As described above, the remainder of the fuel gas is supplied to the power generation device as fuel for driving the power generation device, and the power generation device transmits electric power to the outside of the system as described above.

The waste incineration system thus configured generates a fuel gas (reformed gas) from the pyrolysis gas generated in the pyrolysis apparatus without depending on a heat source outside the system. To remove the harmful substances in the residue by reburning the pyrolysis residue, generate power using fuel gas, and supply electric power to the outside of the system. After undergoing the reforming reaction and the reburning reaction in the reformer and the high-temperature steam generator, the pyrolysis gas of the mixed waste is discharged from the high-temperature steam generator as an exhaust gas containing no harmful substances and unburned components. Is discharged.

Thus, the waste incineration system of each of the above embodiments reduces the content of residues generated during incineration and harmful substances in the combustion exhaust gas, and does not discharge harmful secondary waste to the outside of the system. Configure the system. Therefore, according to the waste incineration system, mixed waste containing various difficult-to-separate waste materials is incinerated in the facility, and the emission of harmful substances is surely prevented.
It is possible to provide a relatively small incinerator that can be used very effectively in the medical facilities and the like.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below in detail with reference to FIGS. FIG. 3 is a schematic flowchart of the waste incineration system according to the first embodiment of the present invention. The waste incineration system constitutes an incineration facility for incinerating mixed waste in a general general hospital.

The waste incineration system shown in FIG. 3 includes an incinerator 1 for thermally decomposing medical waste, a detoxification chamber 2 provided in association with the incinerator 1, and a reformer for reforming a pyrolysis gas with high-temperature steam. , A high-temperature gas cleaning device 5 for cleaning the reformed gas,
A filter 6 for purifying the reformed gas, a heat exchanger 7 for continuously producing low-temperature steam, a neutralizing agent injection device 8 for supplying a neutralizing agent to the high-temperature gas cleaning device 5, a power generating device 9 capable of transmitting power outside the system, and a high-temperature A high-temperature steam generator 10 that continuously generates steam is provided.

Medical waste includes blood, biological waste, chemicals,
The mixed waste containing various waste materials such as synthetic resin, glass, and fibrous material is collectively fed into the incinerator 1 through the waste introduction path MW. The in-furnace region of the incinerator 1 is controlled to a low-oxygen or oxygen-free high-temperature firing atmosphere. The pyrolysis reaction of the waste proceeds in the incinerator 1, and pyrolysis gas is generated in the furnace area. The pyrolysis gas is supplied to the reformer 4 via the pyrolysis gas supply path HG. The reformer 4 includes a pyrolysis gas supply path HG, a high-temperature steam supply path SH1, and a fuel gas supply path F
It consists of a hollow pressure vessel communicating with 1. High-temperature superheated steam (hereinafter, referred to as “high-temperature steam”) is supplied to the reformer 4, and the pyrolysis gas and the high-temperature steam are mixed in a region inside the container of the reformer 4. Hot steam is at least 70
0 ° C., preferably above 800 ° C., and
It has sufficient sensible heat to generate and maintain a steam reforming reaction of hydrocarbons in the pyrolysis gas. The steam reforming reaction of hydrocarbons in the pyrolysis gas proceeds in the presence of high-temperature steam, and the water gasification reaction of high-temperature steam proceeds. As a result, the reformed gas (fuel Gas) is generated in the reformer 4. The reformed gas is sent out as a high-temperature fuel gas to the reformed gas supply path F 1, and is introduced into the high-temperature gas cleaning device 5. The neutralizing agent injection device 8 injects the neutralizing agent into the high-temperature cleaning device 5 via the neutralizing agent injection line AL, and corrosive components such as hydrogen chloride contained in the reformed gas are
It is removed by the hot gas scrubber 5. The reformed gas that has been subjected to the cleaning process in the high-temperature gas cleaning device 5 is introduced into the filter 6 via the reformed gas feed path F2,
After the purification, the high-pressure steam is supplied to the high-temperature steam generator 10 via the reformed gas supply passage F3 and the fuel supply passages FS1 and FS2. The filter 6 is composed of any type of dust removing device or dust collecting device such as a heat-resistant ceramic filter type dust removing device, a bag filter or an electric dust collector.

The upstream end of the fuel gas supply path F6 branches off from the reformed gas supply path F3, and the downstream end of the supply path F6 is connected to the power generator 9. Predetermined ratio of reformed gas (fuel gas)
Is supplied from the feed line F6 to the internal combustion engine of the power generation device 9 as fuel for operating the power generation device 9. The generator of the power generation device 9 generates electric power by driving the internal combustion engine and supplies power to other facilities in the facility such as an air conditioner or an electric facility, or supplies power to other facilities outside the facility. .

The fuel gas branch lines F4 and F5 branch from the reformed gas supply line F3 and are connected to the heat exchanger 7. A water supply pipe CW and a low-temperature steam supply path ST are further connected to the heat exchanger 7. The feed water of the feed pipe CW is supplied to the heat exchanger 7 and vaporized by a heat exchange action with the reformed gas flowing through the fuel gas branch lines F4 and F5, and relatively low-temperature steam, for example, 200 ° C. to 300 ° C. ℃ superheated steam (hereinafter,
"Low-temperature steam" is continuously produced. The low-temperature steam is continuously supplied to the flow path switching device 20 of the high-temperature steam generator 10 via the feed path ST.

The high-temperature steam generator 10 continuously sends out high-temperature steam to the high-temperature steam supply path SH. Supply path SH
Branches to the first and second high-temperature steam supply paths SH1: SH2. The feed path SH1 is connected to the reformer 4 as described above, while the feed path SH2 is connected to the detoxification chamber 2. The decomposition residue of the incinerator 1 is introduced into the detoxification chamber 2 via the decomposition residue introduction path SW, and the high-temperature steam in the feed path SH1 is sprayed on the decomposition residue. As a result, harmful substances, particularly dioxins, in the decomposition residue are decomposed and removed by the high-temperature steam, and thus the decomposition residue of the incinerator 1 is detoxified.

The solidifying agent supply passage SF is connected to the detoxification chamber 2, and a predetermined solidifying agent, preferably a silane-based solidifying agent, is supplied to the detoxified residue. The solid agent prevents scattering of the residue, shapes the residue into an arbitrary form, and facilitates the removal of the residue. The solidified tangible residue lump is carried out of the system as general waste from the waste path WT and is disposed of.

FIG. 4 is a schematic vertical sectional view showing the structure of the incinerator 1 and the detoxification chamber 2. The incinerator 1 includes a furnace body 50 having a waste inlet 51 at the top, and a sloped bottom surface 52 disposed below the furnace body 50. The furnace body 50 is formed as a vertical cylindrical container having an open top, and a top lid 53 capable of closing the waste input port 51 closes the input port 51, thus forming a substantially sealed firing zone 55. Defined inside body 50. The slope bottom surface 55 forms a combustion ash flow zone 56 below the firing zone 55. The combustion ash generated by the firing reaction in the firing zone 55 transiently stays in the flow zone 56 and flows to the detoxification chamber 2 under gravity.

An oxygen supply nozzle 6 is provided on the outer peripheral wall of the furnace body 50.
0, fuel supply nozzle 61, and temperature / oxygen concentration detector 6
2 are disposed. The oxygen supply nozzle 60 is connected to the combustion air supply path CA. An air supply pump 65 capable of controlling a flow rate is interposed in the supply path CA, and the pump 65 pumps combustion air to the oxygen supply nozzle 60 under pressure. The pump 65 is
It is connected to the electronic control unit CU via a control signal line (shown by a broken line). The air flow rate of the pump 60,
Is variably controlled by the electronic control unit CU. Therefore, the oxygen concentration in the firing zone 55 is controlled by the electronic control unit C
It is adjusted under the control of U. The fuel supply nozzle 61 is connected to a fuel supply source (not shown) via a fuel supply path FL. A fuel supply control valve 66 whose opening degree can be controlled is interposed in the fuel supply path FL. The fuel supply control valve 66 is connected to the electronic control unit CU. Under the control of the electronic control unit CU, a hydrocarbon system required for an initial combustion reaction of the waste, particularly, a combustion reaction of the waste immediately after the introduction of the waste. Fuel is introduced into the furnace.
The temperature / oxygen concentration detector 62 is connected to the electronic control unit CU, and inputs each detected value of the atmosphere temperature and the oxygen concentration in the furnace to the electronic control unit CU.

The detoxification chamber 2 has a substantially rectangular parallelepiped housing 70 defining a reaction zone 75.
Is provided with a combustion ash discharge port 71 for discharging the solidified decomposition residue outside the furnace. The discharge port 71 includes an openable and closable lid 73, and the detoxification area 75 is substantially sealed when the openable and closable lid 73 is closed. The detoxification zone 75 communicates with the flow zone 56 via the opening 57. A residue receiver 72 that can receive the decomposition residue of the combustion ash that has flowed down from the flow area 56 is movably disposed on the bottom wall of the detoxification area 75.

A high-temperature steam discharge nozzle 63 and a solidifying agent injection nozzle 64 are provided on the top wall of the housing 70. The discharge nozzle 63 is connected to the high-temperature steam supply path SH2,
A flow control valve 67 is interposed in the feed path SH2. The injection nozzle 64 is connected to the solidifying agent supply passage SF, and a solidifying agent supply pump 68 capable of controlling the flow rate is interposed in the supply passage SF. The upstream end of the supply path SF is connected to a solidifying agent tank 69, and the solidifying agent tank 69 stores a silane-based solidifying agent. The flow control valve 67 and the supply pump 68 are connected to the electronic control unit CU via a control signal line, and the supply path SH2,
The high-temperature steam of the SF and the solidifying agent are introduced into the detoxification zone 75 under the control of the control unit CU.

FIG. 5 is a schematic sectional view showing the overall configuration and operation of the high-temperature steam generator 10. FIG.
FIG. 5 shows a first heating step of the high-temperature steam generator 10, and FIG.
(B) shows a second heating step of the high-temperature steam generator 10.

As shown in FIG. 5, the high-temperature steam generator 10
Is composed of a pair of first and second heating furnaces 10A and 10B, and a communication portion 10C for interconnecting the respective heating furnaces.
The heating furnace 10A includes the first heat exchange device 11 and the first combustion zone 1
3 and the heating furnace 10 </ b> B has a second heat exchange device 12 and a second combustion zone 14. First and second combustion zones 13, 14
Communicates alternately with the low-temperature steam supply path ST via the heat exchange devices 11 and 12 and the flow path switching device 20. Communication part 10
C is formed in a structure symmetrical with respect to the central axis of the high-temperature steam generator 10, and the protruding portion 16 projects inward of the flow path on the central axis. The fuel supply ports 43 and 44 and the oxidant discharge ports 83 and 84 are connected to the first and second heating furnaces 10A and 10A.
B respectively. The fuel supply ports 43 and 44 are connected to the reformed gas supply path F3 (FIG. 3) via the fuel supply paths FS1 and FS2, and discharge or inject the fuel gas into the combustion zones 13 and 14 alternately. The oxidant discharge ports 83 and 84 are connected to the oxidant supply path OXG via the oxidant supply paths OX1 and OX2, and supply the oxidant to the combustion zones 13 and 14 alternately.

The high-temperature steam generator 10 further includes a fuel supply control device 40 for controlling the amount and timing of fuel gas injection into the fuel supply ports 43 and 44, and the oxidant supply amounts and An oxidant supply control device 80 for controlling the supply timing. The control device 40 controls the fuel supply path FS
1, a first fuel supply control valve 41 and a second fuel supply control valve 42, which are respectively interposed in the FS2.
1. First and second flow control valves 8 interposed in OX2, respectively
1, 82. As the oxidizing agent, air or oxygen whose oxygen concentration is adjusted is generally used.

The first and second heat exchangers 11 and 12 are made of a ceramic heat storage body having a honeycomb structure having a large number of cell holes, and each cell hole has a flow passage through which steam and flue gas can alternately pass. Is configured. As this kind of heat storage body, a ceramic honeycomb structure having a large number of narrow channels (cell holes) can be suitably used. The heat storage body is a heating furnace 10A,
10B has an overall shape and dimensions that can be incorporated into the inside of 10B,
The wall thickness of the cell walls and the pitch of each cell wall (wall spacing) preferably correspond to the maximum value of the volumetric efficiency of the regenerator and is equal to 0.1.
The desired wall thickness and pitch are set so as to ensure the temperature efficiency of the heat exchange devices 11 and 12 within the range of 7 to 1.0.

A branch 15 located between the first and second combustion zones 13 and 14 is connected to the upstream end of the high-temperature steam supply passage SH, and is connected to the base of each of the first and second heat exchangers 11 and 12. Is connected to the low-temperature steam supply path ST via the flow path switching device 20.
And the exhaust outlet path EX. Channel switching device 20
Is provided with a first air supply on-off valve 21, a second air supply on-off valve 22, a first exhaust on-off valve 23, and a second exhaust on-off valve 24. The air supply on-off valves 21 and 22 communicate with each other via a branch communication pipe 25 of the feed path ST, and the exhaust on-off valves 23 and 24 communicate with each other via a branch communication pipe 26 of the exhaust outlet path EX. .

First air supply on-off valve 21 and first exhaust air on-off valve 2
3 are interlocked to open simultaneously and close simultaneously;
The second air supply opening / closing valve 22 and the second exhaust air opening / closing valve 24 are linked to open simultaneously and close simultaneously. In the first heating step shown in FIG. 5A, the control device (not shown) of the high-temperature steam generator 10
The exhaust on-off valve 23 is opened and the second air supply on-off valve 22 and the second exhaust on-off valve 24 are closed. On the other hand, in the second heating step shown in FIG. 5B, the control device of the high-temperature steam generator 10 closes the first air supply opening / closing valve 21 and the first exhaust gas opening / closing valve 23 and the second air supply opening / closing valve 22. And the second exhaust on-off valve 24 is opened.

Next, the operation of the waste incineration system having the above configuration will be described. As shown in FIG. 4, mixed waste of medical facilities including solid, liquid, and semi-solid waste materials is collectively charged into the incinerator 1 from a waste input port 51, and an oxygen supply nozzle 60 and a fuel supply nozzle 61 are provided. Is initially burned by the combustion air and the fuel supplied by the fuel cell. Supply nozzles 60, 6
1 restricts the supply amounts of combustion air and fuel under the control of the electronic control unit CU, and the firing zone 55 is controlled to a low-oxygen or oxygen-free high-temperature firing atmosphere. Thus, incinerator 1
, The mixed waste is steamed in a furnace, and the mixed waste in the firing zone 55 is thermally decomposed in a high-temperature and low-oxygen firing atmosphere. The pyrolysis gas generated by the pyrolysis reaction of the mixed waste is supplied to the reformer 4 via the pyrolysis gas feed line HG, and the pyrolysis residue is sent to the residue receiver 72 along the slope bottom surface 52.
Flows in.

The high-temperature steam discharge nozzle 63 sprays high-temperature steam on the residue in the receiver 72, and harmful substances (such as residual dioxin) in the residue are destroyed and thermally decomposed. The solidifying agent injection nozzle 64 discharges the solidifying agent to the residue obtained by decomposing and removing the harmful substance, and solidifies the fluid residue including combustion ash and fly ash. The solidified residue waste is
As a residue lump shaped into a predetermined shape, the combustion ash outlet 71
From the furnace.

As shown in FIG. 3, the pyrolysis gas in the calcination zone 55 is introduced into the reformer 4 via the feed line HG. The high-temperature steam of the high-temperature steam generator 10 is supplied to the high-temperature steam supply path SH.
The pyrolysis gas is introduced into the reformer 4 via 1 and is mixed with high-temperature steam. Steam in an ultra-high temperature range exceeding 700 to 800 ° C. has sufficient sensible heat to generate and maintain a steam reforming reaction of the pyrolysis gas. The steam reforming reaction of hydrocarbons in the pyrolysis gas and the water gasification reaction of high-temperature steam proceed. As a result of the steam reforming reaction and the water gasification reaction,
A reformed gas containing a relatively large amount of carbon, carbon monoxide and hydrogen is generated, and the reformed gas is cleaned of corrosive components such as hydrogen chloride in a high-temperature gas scrubber 5 and purified by a filter 6. The fuel gas is supplied to the high-temperature steam generator 10 and the power generator 9 from the fuel gas supply paths F3 and F6. The reformed gas (fuel gas) in the feed path F3 partially circulates through the heat exchanger 7 to heat the feedwater supplied to the heat exchanger 7. The feedwater is vaporized and supplied to the flow path switching device 20 of the high-temperature steam generator 10 as low-temperature steam.

In the first heating step, the flow path switching device 20 introduces low-temperature steam into the first combustion zone 13 and
The exhaust gas from the combustion zone 14 is led out to the exhaust outlet EX (FIG. 5A), and in the second heating step, low-temperature steam is introduced into the second combustion zone 14 and the flue gas from the first combustion zone 13 is passed to the exhaust outlet EX. (FIG. 5B).

In the first heating step (FIG. 5A), the fuel supply control device 40 blows the reformed gas (fuel gas) into the second combustion zone 14, and the oxidant supply control device 80 supplies the oxidant to the second combustion zone 14. It is supplied to the combustion zone 14. The low-temperature steam is heated to a high temperature range of 700 ° C. or higher, preferably 800 ° C. or higher while flowing through the first heat exchange device 11. The high-temperature steam flow H flows into the branch 15, where the first stream
And a second high-temperature steam flow H1: H2. The second steam flow H2 is sent out to the high-temperature steam supply passage SH, and the first steam flow H1 flows into the second combustion zone 14, and mixes with the reformed gas (fuel gas) and the oxidant to cause a combustion reaction. Hot combustion exhaust gas is generated in the second combustion zone 14. The combustion exhaust gas is exhausted out of the system via the second heat exchange device 12, the second supply / discharge path L2, and the first exhaust opening / closing valve 23. The flue gas is second
When passing through the heat exchange device 12, it comes into heat transfer contact with the heat storage body of the second heat exchange device 12, and the sensible heat held by the flue gas flow is stored in the heat storage body.

In the second heating step (FIG. 5B), the low-temperature steam is heated to the ultra-high temperature range while flowing through the second heat exchanger 12. The high-temperature steam flow H flows into the diversion area 15, where the first and second high-temperature steam flows H flow.
1: Divide into H2. The second steam flow H2 is sent to the high-temperature steam supply passage SH. The control devices 40 and 80 supply the reformed gas (fuel gas) and the oxidant to the first combustion zone 13. The first steam flow H <b> 1 flows into the first combustion zone 13, mixes with the reformed gas (fuel gas) and the oxidant, and generates high-temperature combustion exhaust gas in the first combustion zone 13. The flue gas is the first
Heat exchange device 11, first supply / discharge path L1, and second exhaust opening / closing valve 2
The exhaust gas is exhausted out of the system via 4. When the flue gas passes through the first heat exchange device 11, the flue gas makes heat transfer contact with the heat storage body of the first heat exchange device 11, and the sensible heat of the flue gas flow is stored in the heat storage material.

The high-temperature steam generator 10 operates for 120 seconds or less,
Preferably, the first or the second is alternately performed at a predetermined time interval set to a predetermined time of 60 seconds or less, more preferably 40 seconds or less.
The mode is switched to the heating step, and the second steam flow H2 is continuously sent to the high-temperature steam supply path SH. As shown in FIG.
The high-temperature steam in the supply path SH is introduced into the reformer 4 through the supply path SH1, and is introduced into the detoxification chamber 2 through the supply path SH2.

FIG. 6 is a schematic flow chart showing a waste incineration system according to a modification of the first embodiment. The waste incineration system shown in FIG. 6 has an incinerator 1, a detoxification chamber 2, a reformer 4, a high-temperature gas scrubber 5, a heat exchanger having substantially the same structure and function as the embodiment shown in FIG. 7 and a high-temperature steam generator 10 and heat exchangers 3 and 7 for generating low-temperature steam. The high-temperature pyrolysis gas in the pyrolysis gas supply passage HG flows through the heat exchanger 3 and heats the water supplied to the heat exchanger 3. The feed water is vaporized as low-temperature steam, and is supplied to the high-temperature steam generator 1 through the low-temperature steam supply path ST.
0 is supplied to the channel switching device 20. The pyrolysis gas is cooled by heat exchange with the feedwater, and is introduced into the reformer 4 through the pyrolysis gas delivery path CG. On the other hand, the heat exchanger 7 includes the reformed gas passages F1 and F
2 interposed. The reformed gas of the reformer 4 flows through the heat exchanger 7 and heats water supplied to the heat exchanger 7 from the water supply pipe CW ′. The feedwater is vaporized as steam having a general superheated temperature, and is sent out of the system via a steam delivery passage ST ′.

FIG. 7 is a schematic flowchart showing a waste incineration system according to a further modification of the first embodiment. The waste incineration system shown in FIG. 7 has a configuration similar to that of the waste incineration system shown in FIG. However, FIG.
In the waste incineration system shown in FIG.
Is connected to a reduced water supply pipe 91 of the electrolysis device 90. The reduced water of the electrolysis device is supplied to the high-temperature gas cleaning device 5 through the feed pipe 91, and after cleaning the high-temperature reformed gas (fuel gas), is drained through the drain pipe 92.

In the embodiment shown in FIGS. 6 and 7, the waste incineration system uses the sensible heat of the reformed gas to generate steam at a general superheated temperature, and converts the steam to outside of the system. Send to steam consumption system. That is, the waste incineration system shown in FIG. 3 outputs waste heat recovered in the system as electric energy to the outside of the system, whereas the waste incineration system shown in FIGS. 6 and 7 recovers in the system. Waste heat is sent out of the system as a heat medium fluid (steam).

FIG. 8 is a schematic flow chart of a waste incineration system according to a second embodiment of the present invention. In FIG. 8, components that are substantially the same as or equivalent to the components of the first embodiment are given the same reference numerals.

The waste incineration system shown in FIG. 8 has an incinerator 1, a reformer 4, and a high-temperature gas scrubber 5 having substantially the same structure and function as each component of the waste incineration system shown in FIG. , Filter 6, heat exchanger 7, neutralizer injection device 8
And a high-temperature steam generator 10. However, the waste incineration system of this embodiment is different from the detoxification chamber described above in that the secondary combustion chamber 2 for reburning the pyrolysis residue of the incinerator 1 is used.
Is provided. A fuel gas branch path F7 branched from the reformed gas supply path F3 is connected to the secondary combustion chamber 2, and the fuel gas (reformed gas) purified by the filter 6 is introduced into the secondary combustion chamber 2. The secondary combustion chamber 2 has the same structure as the detoxification chamber of the first embodiment, but the high-temperature steam discharge nozzle 63 and the solidifying agent injection nozzle 64 are used as a fuel gas discharge nozzle and an oxidant discharge nozzle. Is done. Fuel gas and oxidant (or combustion air) introduced into the secondary combustion chamber 2
Generates and maintains a secondary combustion reaction of the pyrolysis residue flowing from the firing zone 50 of the incinerator 1. The pyrolysis residue is secondarily burned in a high-temperature atmosphere of 800 ° C. or more by supplying a fuel gas, and harmful substances in the decomposition residue, particularly, residual dioxin are decomposed and removed by the second combustion reaction.

The other structure is substantially the same as that of the first embodiment, so that a further detailed description will be omitted. FIG. 9 is a schematic flowchart showing a waste incineration system according to a modification of the second embodiment.

The waste incineration system shown in FIG. 9 has an incinerator 1, a secondary combustion chamber 2, a reformer 4, and a high-temperature gas scrubber 5 having substantially the same structure and function as the embodiment shown in FIG. , A filter 6 and a high-temperature steam generator 10 and heat exchangers 3 and 7 for generating low-temperature steam. The heat exchangers 3 and 7 heat the feed water of the feed pipes CW and CW ',
The feed water is vaporized as low-temperature steam, and the low-temperature steam feed path S
T, ST '.

FIG. 10 is a schematic flowchart showing a waste incineration system according to a further modification of the second embodiment.
The waste incineration system shown in FIG. 10 has a configuration similar to that of the waste incineration system shown in FIG. 9, but in the waste incineration system shown in FIG. The reduced water of the electrolysis device is connected to the feed pipe 91 and is supplied to the high-temperature gas cleaning device 5 through the feed pipe 91 to wash the high-temperature reformed gas (fuel gas). Drained.

According to the embodiment shown in FIGS. 9 and 10, the waste incineration system uses the sensible heat of the reformed gas to generate relatively low-temperature steam. While being supplied from ST to the high-temperature steam generator 10,
The water is sent from the feed path ST ′ to a water vapor consuming system outside the system.

Although the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, and various modifications may be made within the scope of the present invention described in the appended claims. Or it can be changed.

For example, as the incinerator, another type of pyrolysis furnace such as a continuous charging type rotary kiln type pyrolysis furnace or an external heating type pyrolysis furnace may be used. Further, as means for outputting the energy recovered from waste heat to the outside of the system, a boiler or a heat cycle engine using sensible heat held by the pyrolysis gas and / or the reformed gas, or a Stirling using the reformed gas as a fuel An engine or the like may be used.

[0070]

As described above, according to the above configuration of the present invention, mixed waste such as a medical facility is incinerated in the facility, and incineration residues generated during incineration and harmful substances in combustion exhaust gas are eliminated. A relatively small-scale waste incineration system and a waste incineration method that reduce the content can be provided.

The present invention further provides a medical facility by providing a power generator for driving the reformed gas as fuel, or a heat exchange device for outputting the sensible heat of the pyrolysis gas or the reformed gas to the outside of the system. In addition to incinerating mixed waste such as in the same facility, waste incineration that converts the waste heat of the combustion exhaust gas generated during incineration into energy that can be used effectively and enables the effective use of waste heat A system and a waste incineration method can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic block flow diagram illustrating an entire configuration of a waste incineration system according to a first embodiment of the present invention.

FIG. 2 is a schematic book flow diagram showing an overall configuration of a waste incineration system according to a second embodiment of the present invention.

FIG. 3 is a schematic flow chart showing a first embodiment of the waste incineration system according to the present invention. The waste incineration system constitutes an incineration facility for incinerating mixed waste in a general general hospital.

FIG. 4 is a schematic vertical sectional view showing the structure of the incinerator and the detoxification chamber shown in FIG.

FIG. 5 is a schematic cross-sectional view showing the overall configuration and operation of the high-temperature steam generator shown in FIG. 3; FIG. 5A shows a first heating step of the high-temperature steam generator; Indicates a second heating step of the high-temperature steam generator.

FIG. 6 is a schematic flow chart showing a waste incineration system according to a modification of the first embodiment (FIG. 4).

FIG. 7 is a schematic flowchart showing a waste incineration system according to a further modification of the first embodiment.

FIG. 8 is a schematic flow chart showing a second embodiment of the waste incineration system according to the present invention.

FIG. 9 is a schematic flowchart showing a waste incineration system according to a modification of the second embodiment (FIG. 8).

FIG. 10 is a schematic flowchart showing a waste incineration system according to a further modification of the second embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 incinerator 2 detoxification chamber, secondary combustion chamber 3, 7 heat exchanger 4 reformer 5 high-temperature gas scrubber 6 filter 8 neutralizer injection device 9 power generation device 10 high-temperature steam generator

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F23G 5/027 ZAB F23G 5/46 ZABZ 5/14 ZAB B09B 3/00 ZAB 5/46 ZAB 303J F term ( (Reference) 3K061 AA18 AA23 AB01 AB02 AC01 AC20 BA04 CA01 DA12 DA17 DA18 DB20 EB12 EB18 3K065 AA18 AA23 AB01 AB02 AC01 AC20 BA04 HA01 HA03 HA05 3K078 AA04 AA08 BA03 BA26 CA02 CA21 4D004 AA04 AA04 CC03 BA03 DA03 CC 4H029 CA01 CA08 CA12

Claims (15)

[Claims] 1. A waste incineration system for incinerating mixed waste, comprising: a pyrolysis apparatus having a firing zone in a low oxygen concentration or oxygen-free atmosphere; A cracker, a reformer for reforming a pyrolysis gas of the pyrolyzer, and a high-temperature steam generator for generating high-temperature steam of 700 ° C. or higher. Waste incineration system characterized by being introduced into a secondary pyrolysis unit. 2. A waste incineration system for incinerating mixed waste, comprising: a pyrolysis device having a firing zone in a low oxygen concentration or oxygen-free atmosphere; a secondary pyrolysis device having a secondary combustion zone for decomposition residues; A reformer for reforming the pyrolysis gas of the pyrolyzer; and a high-temperature steam generator for generating high-temperature steam of 700 ° C. or higher, wherein the high-temperature steam is introduced into the reformer, A waste gas incineration system, wherein the reformed gas of the reformer is introduced into the secondary combustion zone. 3. The waste incineration system according to claim 1, further comprising a power generator, wherein the power generator includes an internal combustion engine that operates using the reformed gas as fuel. 4. The apparatus further comprises a heat exchange device through which the pyrolysis gas and / or the reformed gas can flow.
The waste incineration system according to any one of claims 1 to 3, wherein the heat medium fluid is heated by the sensible heat of the gas. 5. The heating medium fluid after heating is low-temperature steam to be supplied to the high-temperature steam generation device, and the high-temperature steam generation device heats the low-temperature steam to a high-temperature region of 800 ° C. or more. The waste incineration system according to claim 4, characterized in that: 6. The waste incineration system according to claim 4, wherein the heating medium fluid after heating is steam that can be supplied to equipment outside the system of the waste incineration system. 7. The secondary pyrolysis apparatus has high-temperature steam introduction means for introducing the high-temperature steam into the reaction zone, wherein the reaction zone communicates with the calcination zone, and the decomposition residue includes The waste incineration system according to claim 1, wherein the waste incineration system flows into the reaction zone and undergoes secondary pyrolysis in the presence of the high-temperature steam in the reaction zone. 8. The waste incineration system according to claim 7, wherein the secondary pyrolysis device includes a solidifying agent injection means for injecting a solidifying agent into the reaction zone. 9. The secondary pyrolysis apparatus has a reformed gas introduction unit for introducing the reformed gas into the secondary combustion zone, wherein the secondary combustion zone communicates with the firing zone, 3. The waste incineration system according to claim 2, wherein the decomposition residue flows into the secondary firing zone, and undergoes secondary thermal decomposition by the combustion heat of the reformed gas in the combustion zone. 10. A waste incineration method for incinerating mixed waste in which wastes of various properties and physical properties are mixed, wherein the mixed waste is thermally decomposed to generate a pyrolysis gas.
The pyrolysis gas is reformed into fuel gas by high-temperature steam of 0 ° C. or more, and the high-temperature steam is generated using the combustion heat of the fuel gas as a heat source, and the decomposition residue of the waste is secondarily pyrolyzed by the high-temperature steam. Waste incineration method. 11. A waste incineration method for incinerating mixed waste in which wastes of various properties and physical properties are mixed, wherein the mixed waste is thermally decomposed to generate a pyrolysis gas.
The pyrolysis gas is reformed into a fuel gas by high-temperature steam of 0 ° C. or more, and the high-temperature steam is generated by using the heat of combustion of the fuel gas as a heat source. Wherein the decomposition residue is subjected to secondary combustion with the fuel gas. 12. The waste incineration method according to claim 10, wherein the fuel gas is supplied as a working fuel to a power generator, and the power generator is driven. 13. The steam according to claim 10, wherein low-temperature steam is generated by the sensible heat of the pyrolysis gas and / or the fuel gas, and the low-temperature steam is heated to the high-temperature steam. 2. The waste incineration method according to claim 1. 14. The steam generated by the sensible heat of the pyrolysis gas and / or the fuel gas, and the steam is sent out of the waste incineration system. The waste incineration method according to any one of claims 1 to 4. 15. The waste incineration method according to claim 10, wherein a solidifying agent is supplied to the residue after the second pyrolysis, and the residue is solidified into a tangible residue mass.