JP2004239502A - Incinerating plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clean incinerating plant with high operating efficiency for purifying smoke or odored gas arising from the incineration of flammable materials while sealing them in a closed system and completely prohibiting the release of dioxine into the atmosphere. <P>SOLUTION: A smoke feed pipe 3, a smoke return pipe 4 and a smoke return blower 14 are used for circulating gas including the smoke and the odored gas between an incinerator 1 and a purifying tank 2 many times to purify the smoke and the odored gas in the closed circulation system. Specifically, the smoke and the odored gas passing through water in the purifying tank 2 many times are purified to be deodorized and rendered harmless and the smoke and the odored gas not completely purified once are returned into the incinerator 1 and purified in the high-temperature incinerator to be deodorized and rendered harmless. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an incineration plant for incinerating combustible materials such as industrial waste and garbage from households, and in particular, purifies the smoke (odor and harmlessness) by sealing the smoke and odorous gas from the incineration of the combustible materials in a closed system. The present invention relates to a clean and highly efficient incineration plant that does not allow any release of dioxin into the atmosphere.
[0002]
[Prior art]
Conventionally, as an apparatus for incinerating this kind of combustible material, for example, an incinerator disclosed in Japanese Patent Application Laid-Open No. 7-171329 is known. In this incinerator, a gas containing odorous gas and smoke is introduced into the water, and fine particles such as odorous gas and smoke suspended in the gas are captured in the water. A purification treatment structure such as purification with ozone is adopted.
[0003]
However, according to the above-mentioned conventional incinerator, an open cycle in which the gas after the purification treatment is finally released to the atmosphere is employed as the purification cycle of the gas containing odorous gas, smoke and the like. For this reason, odorous gas, smoke, and the like that cannot be completely purified may be released into the atmosphere. In particular, the possibility is high when the purification process using water, ozone, or the like is insufficient, or when some trouble occurs in the purification process. In addition, when the emission of odorous gas or smoke is found in the atmosphere, the operation of the incinerator must be stopped to find the cause of the emission, and there is a problem that the operating efficiency of the incineration equipment is reduced.
[0004]
[Patent Document 1]
JP-A-7-171329
[0005]
[Problems to be solved by the invention]
The present invention has been made in order to solve the above-mentioned problems, and an object thereof is to purify smoke and odor gas generated by incineration of combustibles by sealing the smoke and odor gas in a closed system to reduce the emission of dioxin to the atmosphere. An object of the present invention is to provide a clean and highly efficient incineration plant that is not allowed.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an incinerator for incinerating combustibles in a closed furnace, air supply means for supplying combustion air to the incinerator, and a furnace for the incinerator. A purifying tank storing water for purifying smoke, odor gas, etc. generated in the inside, and one end communicates with the furnace of the incinerator, and the other end opens below the water level in the purifying tank. A smoke return pipe, one end of which communicates with the space above the water surface in the purification tank, and the other end opens into the furnace of the incinerator, and the smoke return pipe from the space above the water surface in the purification tank. And gas transfer means for sending gas back into the incinerator through the above.
[0007]
In the present invention, using the smoke feed pipe, the smoke return pipe, and the gas transfer means, smoke and odor gas are circulated many times between the incinerator and the purification tank, and in this closed circulation system, Purify smoke and odor gas, etc.Specifically, purify smoke and odor gas by passing smoke and odor gas etc. many times into the water of the purification tank, and purify smoke and odor gas etc. in the incinerator furnace. It is returned and the odor and harmless purification is performed by the high heat in the furnace. When the temperature in the incinerator is equal to the decomposition temperature of dioxin, dioxin refluxing in the closed circulation system is also decomposed in the incinerator to be harmless.
[0008]
In the present invention, the in-furnace temperature of the incinerator is controlled by dioxin by adjusting the supply amount of combustion air from the air supply means based on a detection value of a temperature sensor that detects the in-furnace temperature of the incinerator. You may employ | adopt the structure provided with the control means which controls so that it may become higher than decomposition temperature.
[0009]
In the present invention, as the in-furnace communication structure at one end of the smoke feed pipe, a plurality of large-diameter short pipes are installed radially around the furnace upper periphery of the incinerator, and one end of the large-diameter short pipe is connected to the incinerator. A structure that opens into the furnace, and a large-diameter annular pipe is formed annularly along the outer periphery of the upper part of the incinerator, and the other end of the large-diameter short pipe and one end of the smoke feed pipe are formed on the large-diameter annular pipe. An opening structure can be adopted.
[0010]
In the present invention, a configuration may be adopted in which sludge treatment means is provided for collecting sludge settled at the bottom of the purification tank and returning the sludge to the inside of the incinerator.
[0011]
Regarding the sludge treatment means, for example, a sludge outlet with a lid is provided at the bottom of the purification tank, a sludge tank is installed immediately below the sludge outlet, and the sludge is disposed between the sludge tank and the incinerator. A structure system in which a screw conveyor for transferring sludge from the bottom of the tank into the furnace of the incinerator can be adopted.
[0012]
Further, as another sludge treatment means, a sludge outlet with a lid is provided at the bottom of the purification tank, sludge is taken out from the sludge outlet, and the sludge taken out is mixed with combustible materials such as sawdust and solidified to form an incinerator. A sludge treatment system in which the sludge is introduced into the furnace may be employed.
[0013]
In the present invention, a configuration may be adopted in which a water level control means for controlling the water level of the purification tank is provided so that the other end of the smoke feed pipe is always immersed below the water surface in the purification tank.
[0014]
The water level control means includes, for example, a water level detection box provided on the upper outer surface of the purification tank and communicating with the purification tank and set to the same water level as the water level of the purification tank; A float floating above the water surface in the box and moving up and down in conjunction with fluctuations in the water level in the water level detection box, and opening and closing a water supply pipe to the purification tank in conjunction with the up and down movement of the float A configuration including a valve can be employed.
[0015]
In the present invention, the incinerator has a structure in which combustibles are introduced into the furnace from an upper surface opening thereof, and the upper surface opening is completely sealed by a lid structure after the combustibles are introduced. be able to.
[0016]
In the present invention, with respect to the incinerator, a fire inlet is provided on the side of the furnace, and a fire is charged into the furnace from the fire inlet, and after the combustible material in the furnace is ignited by the fire, It is also possible to adopt a structure in which the fire inlet is completely sealed with a lid.
[0017]
In the above invention, the incinerator comprises a top-opening type housing composed of a side plate structure and a bottom plate structure, and a lid structure detachably attached to the top surface opening. It is preferable that the bottom plate structure and the lid structure have a water jacket structure having a flowing water passage through which cooling water flows. This is because in the present invention, it is assumed that the temperature inside the incinerator is 1000 ° C. or higher, so that it is difficult to cool the incinerator by air cooling.
[0018]
In the present invention, the gas transfer means is disposed between one end of the smoke return pipe and a space above the water surface in the purification tank, and removes the gas from the space above the water surface in the purification tank. A structure including a blower that forcibly sends back gas into the incinerator through the above may be adopted.
[0019]
The present invention employs a structure in which a rectifier is installed between one end of the smoke return pipe and the space above the water surface in the purification tank as a means for preventing the water surface in the purification tank from waving. You may.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0021]
FIG. 1 is a front view of an incineration plant according to an embodiment of the present invention, FIG. 2 is a top view of the incineration plant of FIG. 1, and FIG. 3 is a conceptual diagram of the incineration plant of FIG. An incineration plant according to an embodiment will be described.
[0022]
The incineration plant according to the present embodiment has a plant structure including structures such as an incinerator 1 and a purification tank 2 and a piping system such as a smoke feed pipe 3 and a smoke return pipe 4 arranged around these structures. Take.
[0023]
The incinerator 1 includes a top-opening type housing composed of a side plate structure 1-1 and a bottom plate structure 1-2, and a lid structure 1-3 detachably attached to the upper surface opening 1a. It has a box shape.
[0024]
In the incinerator 1, combustibles are burned in the closed furnace, that is, in a closed space surrounded by the side plate structure 1-1, the bottom plate structure 1-2, and the lid structure 1-3.
[0025]
The combustibles are introduced into the incinerator 1 through the upper opening 1a of the incinerator 1. The upper opening 1a is provided only when the combustible is introduced or when the furnace is maintained. 3 is opened. At other times, specifically, the upper surface opening 1a is completely sealed by the lid structure 1-3 from the time when the combustibles are charged until the incineration is completed.
[0026]
On the bottom side of the incinerator 1 is provided a snorkel-shaped rooster 5. Further, the bottom plate structure 1-2 of the incinerator 1 located below the rostral 5 has a V-shaped valley shape as a whole, and a screw conveyor 6 is installed at the V-shaped valley bottom side. The screw conveyor 6 is provided as means for discharging ash and the like accumulated at the bottom of the incinerator 1 to the outside of the furnace.
[0027]
Therefore, in the case of the present embodiment, the combustibles charged into the incinerator 1 as described above are placed on the roaster 5 and burned and incinerated. At this time, the ash and the like from the incineration fall through the roaster 5 and fall on the bottom inside the incinerator 1, that is, onto the bottom plate structure 1-2. The fallen ash etc. slides down on the V-shaped slope of the bottom plate structure 1-2 by its own weight, gathers on the screw conveyor 6 located at the bottom of the V-shaped slope, and is discharged to the outside of the furnace by the screw conveyor 6. You.
[0028]
The side plate structure 1-1 which forms the furnace side surface of the incinerator 1 is provided with a fire inlet 7. In the present embodiment, a fire is charged into the incinerator 1 from the fire input 7. After the combustible material in the furnace is ignited by the fire, the fire inlet 7 is completely closed by the lid 8.
[0029]
Each of the side plate structure 1-1, the bottom plate structure 1-2, and the lid structure 1-3 constituting the incinerator 1 has a water jacket structure having a flowing water passage 9 in which cooling water flows. This is because the furnace temperature of the incinerator 1 becomes a high temperature of 1000 ° C. or more, so that the furnace structures that are directly exposed to the high temperature, such as the side plate structure 1-1, the lid structure 1-2, the lid structure 1-3, etc. This is for effectively preventing thermal deformation, thermal damage, and the like. The water supply pipe 9-1 is a means for supplying cooling water to the flowing water passage 9 in the side plate structure 1-1, the bottom plate structure 1-2, and the lid structure 1-3.
[0030]
A blower 10 (hereinafter, referred to as a combustion air supply blower) is provided outside the incinerator 1 as a means for supplying combustion air into the furnace. The air ejection port 10-1 of the combustion air supply blower 10 is configured to communicate with the lower part of the roaster 5 in the incinerator 1 via a heat-resistant hose 10-2.
[0031]
When the combustion air supply blower 10 operates, air is sent from the air outlet 10-1 to the lower part of the roaster 5 in the furnace, and the combustion air is supplied from the lower part of the roaster 5 toward the upper combustible material. Is done.
[0032]
It has been confirmed by an experiment in a test plant that the temperature in the incinerator 1 becomes 1000 ° C. or more during incineration of combustibles. This furnace temperature of 1000 ° C. or higher was obtained only by the self-combustion of wood when incinerated. On the other hand, it is said that dioxin generated during incineration is generated by low-temperature combustion, and decomposes when the temperature exceeds 900 ° C., thereby eliminating toxicity. Therefore, in the present embodiment, 900 ° C. is set as the dioxin decomposition temperature, and in order to decompose dioxin in the incinerator 1, the incinerator 1 is set so that the temperature in the incinerator 1 does not become 900 ° C. or less. The furnace temperature was controlled and managed.
[0033]
Various methods are conceivable for controlling the temperature inside the incinerator 1. In the present embodiment, as a control method, a thermocouple 17 is installed in the incinerator 1 as a temperature sensor for detecting the temperature inside the incinerator 1, and a combustion sensor based on a detection value from the thermocouple 17 is used. A control method is adopted in which the number of rotations of the air supply blower 10 is adjusted to change the amount of combustion air supplied from the combustion air supply blower 10 to the incinerator 1.
[0034]
Specifically, when the temperature in the incinerator 1 once becomes 1000 ° C. or higher and then decreases to around 900 ° C., the rotation speed of the combustion air supply blower 10 increases. Thereby, the supply amount of the combustion air from the combustion air supply blower 10 into the incinerator 1 increases, the combustion of combustibles in the incinerator 1 is promoted, and the temperature inside the incinerator 1 rises. . When the furnace temperature exceeds 900 ° C. and recovers to 1000 ° C., for example, the number of revolutions of the combustion air supply blower 10 decreases.
[0035]
The purification tank 2 stores therein water for purifying smoke, odor gas and the like generated in the incinerator 1. The water level in the purification tank 2 is always controlled to be slightly lower than when the tank is full. Therefore, a clearance space without water (hereinafter, referred to as a space G above the water surface) is formed above the water surface in the purification tank 2. The control means for controlling the water level in the purification tank 2 will be described later.
[0036]
The smoke feed pipe 3 is a piping system that sends smoke, odor gas, and the like to the purification tank 2 side in order to purify the smoke, odor gas, and the like in the furnace of the incinerator 1 with the purification tank 2.
[0037]
Due to the function or role of the smoke feed pipe 3 as described above, one end 3a of the smoke feed pipe 3 communicates with the inside of the incinerator 1, and the other end 3b of the smoke feed pipe 3 is purified. It is structured to open below the water surface in the tank 2.
[0038]
Various types of the in-furnace communication structure of the one end 3a of the smoke feed pipe can be considered. In the present embodiment, as an example of the structure, in order to be able to sufficiently send smoke, odor gas, and the like in the furnace of the incinerator 1 to the purification tank 2 side, radially around the furnace upper periphery of the incinerator 1 is used. A structure in which a plurality of large-diameter short pipes 11 are installed at regular intervals, and one end 11a of these large-diameter short pipes 11 is opened in the furnace of the incinerator 1, and a large-diameter annular pipe is formed along the outer periphery of the furnace. The large-diameter annular pipe 12 has a structure in which the other end 11b of the large-diameter short pipe 11 and one end 3a of the smoke feed pipe 3 are opened. In the case of this structure, gas including smoke and odor gas in the furnace of the incinerator 1 is first sucked into a plurality of large-diameter short pipes 11 protruding like an octopus from the outer periphery of the furnace. Then, the gas passes through the large-diameter annular pipe 12 around the large-diameter short pipe 11 and moves to the one end 3a side of the smoke feed pipe 3.
[0039]
The water level in the purification tank 2 is controlled and managed so that the other end 3b of the smoke feed pipe 3 as described above always keeps a water level sufficiently immersed below the water surface in the purification tank 2. This is because if the other end 3b of the smoke feed pipe 3 is slightly exposed on the water surface, the effect of purifying smoke, odor gas and the like by water is reduced.
[0040]
Various specific configurations of the water level control means 13 for controlling and managing the water level of the purification tank 2 as described above are conceivable. In this embodiment, as a structural example of the water level control means 13, a water level detection box 13-1 communicating with the inside of the purification tank 2 is provided on the upper outer surface of the purification tank 2.
[0041]
The water level in the water level detection box 13-1 is set to the same water level as the purification tank 2 by the water introduced from the purification tank 2. In addition, a float 13-2 that moves up and down in association with the fluctuation of the water level in the water level detection box, that is, the fluctuation of the water level of the purification tank 2, is provided above the water surface in the water level detection box 13-1. Further, a valve 13-4 for opening and closing a water supply pipe 13-3 into the purification tank 2 in conjunction with the vertical movement of the float 13-2 is provided in the water level detection box 13-1.
[0042]
In the water level control means 13 having the above-described structure, when the water level in the purification tank 2 drops even a little, the water level in the water level detection box 13-1 similarly drops, and the floating position of the float 13-2 decreases. Then, in conjunction with the lowering of the floating position of the float 13-2, the valve 13-4 of the water supply pipe 13-3 is opened, and water is supplied from the water supply pipe 13-3 to the purification tank 2 side.
[0043]
As a result, the water level in the purification tank 2 and the water level in the water level detection box 13-1 rise in the same manner, and when the float 13-2 rises and returns to the original position, the float 13-2 The valve 13-4 of the water supply pipe 13-3 closes and the water supply to the purification tank 2 via the water supply pipe 13-3 stops in conjunction with the floating position return operation of -2.
[0044]
By performing the water supply and the water supply stop operations as described above, the water level in the purification tank 2 is sufficiently immersed below the water level in the purification tank 2 at the other end 3b of the smoke feed pipe 3 as described above. It is controlled and managed to keep the water level.
[0045]
The smoke return pipe 4 returns the purified smoke, odor gas, and the like into the furnace of the incinerator 1 in order to purify the purified smoke, odor gas, and the like existing in the space G above the water surface of the purification tank 2 again. It is a piping system.
[0046]
Due to the function or role of the smoke return pipe 4 as described above, one end 4a side of the smoke return pipe 4 is inserted into the space G above the water surface in the purification tank 2 via the blower 14 and the rectifier 15 so that the surface of the smoke return pipe 4 has a true shape. The smoke return pipe 4 is communicated from above, and the other end 4b of the smoke return pipe 4 has a structure that opens into the furnace of the incinerator 1.
[0047]
The open position of the other end 4b of the smoke return pipe is on the lower side of the roaster 5 in the incinerator 1, similarly to the air outlet 10-1 of the combustion air supply blower 10. Therefore, the gas returning from the space G above the water surface of the purification tank 2 to the incinerator 1 via the smoke return pipe 4 is mixed with the combustion air supplied from the combustion air supply blower 10.
[0048]
The blower 14 at the one end 4a of the smoke return pipe is disposed between the one end 4a of the smoke return pipe and the space G above the water surface in the purification tank 2 and smoke returns from the space G above the water surface in the purification tank 2. It is provided as gas transfer means for forcibly sending gas back into the incinerator 1 via the pipe 4. Hereinafter, the blower 14 is referred to as a smoke return blower.
[0049]
Due to the function or role of the smoke return blower 14 as described above, the gas suction port 14a side of the smoke return blower 14 communicates with the space G above the water surface in the purification tank 2, and the smoke return blower 14 The gas outlet 14b side is directly connected to one end 4a of the smoke return pipe 4.
[0050]
When the smoke return blower 14 having the above structure operates, the gas in the purification tank 2 is sucked into the gas suction port 14a of the blower 14, and the sucked gas flows from the gas discharge port 14b of the blower 14 into the smoke return pipe. 4 is sent.
[0051]
The rectifier 15 on the one end 4a of the smoke return pipe is disposed between the gas inlet 14a of the smoke return blower 14 and the space G above the water surface in the purification tank 2 and the water surface in the purification tank 2 Is provided as means for preventing the waving phenomenon.
[0052]
It is also conceivable that the rectifier 15 is omitted and the gas inlet 14a of the smoke return blower 14 is opened directly above the space G above the water surface in the purification tank 2. However, in this structure, since the pulsation of the suction force of the smoke return blower 14 directly acts on the water surface in the purification tank 2, the water surface may undulate and the purification tank 2 may vibrate. In the present embodiment, the rectifier 15 is adopted and installed as means for preventing such a problem.
[0053]
The rectifier 15 has a maze-like zigzag passage 15-1 therein. Then, gas is sucked up from the space G above the water surface in the purification tank 2 to the smoke return pipe 4 side through the zigzag passage 15-1. At this time, the zigzag passage 15-1 functions as a means for rectifying the pulsation of the suction force of the smoke return blower 14.
[0054]
Therefore, in the present embodiment employing the rectifier 15 having the above structure, the pulsation of the suction force of the smoke return blower 14 is reduced by the rectifying action of the zigzag passage 15-1 inside the rectifier 15, and the water surface due to the pulsation is reduced. The waving phenomenon is reduced, and the above-mentioned problem due to the waving phenomenon, that is, the vibration of the purification tank 2 and the like can be effectively prevented.
[0055]
A sludge treatment means 16 is provided below the purification tank 2. This sludge treatment means 16 is means for collecting sludge settled at the bottom of the purification tank 2 and returning the sludge to the incinerator 1.
[0056]
Various concrete sludge treatment methods of the sludge treatment means 16 can be considered. In the present embodiment, as an example of the sludge treatment method, a sludge outlet 16-1 with a lid is provided at the bottom of the purification tank 2, and the sludge tank 16-2 is installed immediately below the sludge outlet 16-1. A screw conveyor 16-3 for transferring sludge from the bottom of the sludge tank 16-2 into the furnace of the incinerator 1 is provided between the sludge tank 15-2 and the incinerator 1. ing. The sludge treatment by the sludge treatment means 16 is performed after draining the water in the purification tank 2.
[0057]
When the sludge treatment means 16 having the above structure is adopted, the sludge in the purification tank 2 falls by its own weight into the sludge tank 16-2 from the sludge discharge port 16-1, and is loaded on the screw conveyor 16-3. You. Then, the sludge is transferred into the incinerator 1 by the screw conveyor 16-3. Since the in-furnace temperature of the incinerator 1 is controlled and maintained at 900 ° C. or more, which is the dioxin decomposition temperature, dioxin in the sludge sent into the furnace is decomposed in the incinerator 1 at the next incineration, for example. It is made harmless.
[0058]
Next, the operation of the incineration plant of the present embodiment configured as described above will be described with reference to FIG.
[0059]
When incinerating combustibles in the incineration plant of the present embodiment shown in FIG. 1, first, the combustibles to be incinerated are put into the incinerator 1. This charging operation can be performed by removing the lid structure 1-3 of the incinerator 1.
[0060]
After the completion of the charging of the combustible material, the lid structure 1-3 is attached to the original position. When this installation is completed, the flammable substance charged in the incinerator 1 is ignited.
[0061]
In the ignition operation, the lid 8 of the igniter inlet 7 is opened, a igniter is injected into the furnace of the incinerator 1 from the igniter inlet 7, and the combustible material in the furnace is ignited.
[0062]
After confirming that the combustion has progressed to some extent after ignition, the lid 8 of the ignition port 7 is closed. Thereby, the inside of the incinerator 1 is completely sealed and cut off from the outside world, and the temperature inside the incinerator 1 becomes 1000 ° C. or more due to self-combustion of combustibles in the furnace. The supply of combustion air into the incinerator 1 after the inside of the incinerator 1 is completely sealed is performed via a combustion air supply blower 10.
[0063]
When the incineration of combustibles in the incinerator 1 starts as described above, the smoke return blower 14 operates. Thereby, gas existing in the space G above the water surface in the purification tank 2 is sucked into the smoke return blower 14 via the rectifier 15.
[0064]
The gas sucked into the smoke return blower 14 is further sent into the incinerator 1 through the smoke return pipe 4. As a result, the pressure in the space G above the water surface in the purification tank 2 is reduced, and a negative pressure is generated.
[0065]
Then, due to the negative pressure or the like generated in the purification tank 2 as described above, gases including smoke, odor gas, and the like are successively supplied from the inside of the incinerator 1 to the water surface of the purification tank 2 via the smoke feed pipe 3. It is drawn.
[0066]
The gas containing smoke, odor gas, and the like sent below the surface of the purification tank 2 is bubbled and rises in the water. At the time of passing through the water, smoke and odor gas are purified by water. This purification is based on the fact that water-soluble harmful substance components and odor components contained in smoke, odor gas and the like dissolve in water.
[0067]
Further, the gas after the above-mentioned purification moves to the space G above the water surface, and is then sucked into the smoke return blower 14 via the rectifier 15. Note that the purified gas contains smoke, odorous gas, and the like that could not be purified by one passage through water.
[0068]
The purified gas sucked into the smoke return blower 14 as described above is further forcibly sent into the incinerator 1 through the smoke return pipe 4. The gas containing smoke, odor gas, and the like returned to the furnace of the incinerator 1 in this way is exposed to high heat in the furnace of the incinerator 1 and purified. This purification is based on thermal decomposition of harmful substances and odor contained in smoke and odor gas.
[0069]
In short, in the incineration plant of the present embodiment, gas including smoke and odor gas generated in the incinerator 1 is purified by the incinerator 1 as shown in FIG. 3 unless the operation of the incineration plant is stopped. It circulates repeatedly between the tank 2 and the closed circulation system L so that no smoke or odorous gas is emitted to the outside world. Each time a gas containing smoke, odor gas, or the like passes through the water in the purification tank 2, purification of smoke, odor gas, or the like is performed. Further, gas containing smoke, odor gas, and the like, which could not be completely purified by the single purification, is returned to the furnace of the incinerator 1, and also in this furnace, purification of smoke, odor gas, and the like by high heat is performed.
[0070]
By the way, at the start of combustion of the incinerator 1, the temperature inside the furnace may be low and dioxin may be generated. However, this dioxin also circulates many times between the incinerator 1 and the purification tank 2 together with smoke, odor gas, etc., and dioxin does not come out of the closed circulation system L to the outside world. Then, since the temperature in the incinerator 1 becomes 1000 ° C., which is higher than the dioxin decomposition temperature, the dioxin in the closed circulation system L is completely decomposed and made harmless. Therefore, even dioxin that can be generated in the early stage of combustion is captured in the closed circulation system L and decomposed and made harmless, so that there is no room for generating any dioxin.
[0071]
As described above, according to the incineration plant of the above embodiment, the gas containing the smoke, the odor gas, and the like is provided between the incinerator 1 and the purification tank 2 by using the smoke feed pipe 3, the smoke return pipe 4, and the smoke return blower 14. Is circulated many times to purify smoke and odor gas in the closed circulation system L. More specifically, odor and harmlessness is achieved by passing smoke and odor gas through the water of the purification tank 2 many times. And a structure in which smoke, odorous gas, and the like, which could not be purified by this one-time purification, is returned to the incinerator 1 to purify the odor and harmlessness with high heat in the furnace. Further, according to the incineration plant of the above embodiment, the temperature in the incinerator 1 is controlled and maintained at a temperature equal to or higher than the dioxin decomposition temperature, so that dioxin is also decomposed and made harmless in the closed circulation system L. Therefore, it can be said that the incineration plant of the above embodiment is a clean incineration plant in which smoke, odor gas, and the like resulting from incineration of combustibles are sealed and purified in a closed system, and no release of dioxin to the atmosphere is allowed.
[0072]
Further, since the incineration plant of the above embodiment employs the closed circulation system L (closed cycle) described above as a purification cycle of gas including smoke, odorous gas, and the like, even if the purification process should fail, There is no room for smoke, odor gases, etc. to be released into the atmosphere. Therefore, there is no need to stop the incineration plant immediately when such a failure occurs, and the incineration plant has high operability.
[0073]
In the above-described embodiment, as the sludge treatment method in the purification tank 2, a structure method in which the sludge is introduced into the incinerator 1 by the screw conveyor 15-3 is adopted. For example, a sludge treatment method in which sludge is taken out from the sludge discharge port 15-1 of the purification tank 2 as described above, and the taken out sludge is mixed with combustible materials such as sawdust and solidified and put into the incinerator 1 is adopted. May be.
[0074]
【The invention's effect】
In the incineration plant according to the present invention, using a smoke feed pipe, a smoke return pipe and a gas transfer means, a gas containing smoke, odor gas and the like is circulated many times between the incinerator and the purification tank. Purification of smoke and odorous gas in a closed circulation system, specifically purification and detoxification by passing smoke and odorous gas through the water in the purification tank many times, and this one-time purification A structure is adopted in which gas containing smoke, odorous gas, and the like, which has not been completely purified, is returned to the furnace of the incinerator to purify odorless and harmless with high heat in the furnace. For this reason, if the temperature inside the incinerator becomes the decomposition temperature of dioxin, dioxin is also decomposed and made harmless in the closed circulation system. It is possible to obtain a clean incineration plant that does not permit any emission of dioxin into the atmosphere.
[0075]
Further, according to the incineration plant according to the present invention, since the above-described closed circulation system (closed cycle) is employed as a purification cycle of gas including smoke and odorous gas, even if the purification process fails, Since there is no room for smoke or odor gas to be released into the atmosphere, there is no need to immediately stop this kind of incineration plant when a failure occurs, and it is possible to obtain an incineration plant with high operating efficiency.
[Brief description of the drawings]
FIG. 1 is a front view of an incineration plant according to an embodiment of the present invention.
FIG. 2 is a top view of the incineration plant of FIG.
FIG. 3 is a conceptual diagram of the incineration plant of FIG.
[Explanation of symbols]
1 incinerator
1a Top opening of incinerator
1-1 Side plate structure
1-2 Bottom plate structure
1-3 Lid structure
2 Purification tank
3 Smoke feed pipe
3a One end of the smoke pipe
3b The other end of the smoke pipe
4 Smoke return pipe
4a One end of smoke return pipe
4b The other end of the smoke return pipe
5 Rostor
6 Screw conveyor
7 fire inlet
8 Lid
9 running water passage
9-1 Water supply pipe
10 blower (combustion air supply blower)
10-1 Air outlet
11 Large diameter short pipe
12 Large diameter annular pipe
13 Water level control means
13-1 Water level control box
13-2 Float
13-3 Water supply pipe
13-4 Valve
14 blower (smoke return blower)
14a Gas inlet of smoke return blower
14b Smoke return blower gas outlet
15 Rectifier
15-1 Zigzag passage
16 Sludge treatment means
16-1 Sludge outlet with lid
16-2 Sludge tank
16-3 Screw conveyor
17 Thermocouple (temperature sensor)
G Space above the water surface
L Closed circulatory system (closed cycle)

Claims (13)

An incinerator for burning combustibles in a closed furnace;
Air supply means for supplying combustion air into the incinerator,
A purification tank that stores therein water for purifying smoke, odor gas, and the like generated in the incinerator,
One end communicating with the furnace of the incinerator, and the other end opening below the surface of water in the purification tank;
A smoke return pipe having one end communicating with the space above the water surface in the purification tank and the other end opening into the furnace of the incinerator;
An incineration plant comprising: gas transfer means for sending gas from the space above the water surface in the purification tank to the furnace of the incinerator via the smoke return pipe. By adjusting the supply amount of the combustion air from the air supply means based on the detection value of the temperature sensor for detecting the temperature inside the incinerator, the temperature inside the incinerator is higher than the decomposition temperature of dioxin. The incineration plant according to claim 1, further comprising control means for controlling the incineration plant. As the furnace communication structure at one end of the smoke feed pipe,
A plurality of large-diameter short pipes are installed radially around the furnace upper periphery of the incinerator, and one end of these large-diameter short pipes is opened in the incinerator furnace,
A large-diameter annular pipe is formed annularly along the upper periphery of the incinerator, and the large-diameter annular pipe adopts a structure in which the other end of the large-diameter short pipe and one end of the smoke feed pipe are open. The incineration plant according to claim 1, characterized in that: The incineration plant according to claim 1, further comprising a sludge treatment means for collecting sludge settled at the bottom of the purification tank and returning the sludge to the inside of the incinerator. The above-mentioned sludge treatment means,
A sludge outlet with a lid is provided at the bottom of the purification tank, a sludge tank is installed immediately below the sludge outlet, and a furnace for the incinerator is provided between the sludge tank and the incinerator from the bottom of the sludge tank. 5. The incineration plant according to claim 4, wherein the incineration plant adopts a structure system in which a screw conveyor for transferring sludge is installed. The above-mentioned sludge treatment means,
A sludge treatment method is provided in which a sludge discharge port with a lid is provided at the bottom of the purification tank, sludge is taken out from the sludge discharge port, the extracted sludge is mixed with combustible materials such as sawdust and solidified, and then put into an incinerator furnace. The incineration plant according to claim 4, characterized in that: 2. The incineration according to claim 1, wherein water level control means for controlling the water level of the purification tank is provided so that the other end of the smoke feed pipe is always immersed below the water surface in the purification tank. plant. The water level control means,
A water level detection box provided on the upper outer surface of the purification tank and communicating with the purification tank, and set to the same water level as the water level of the purification tank;
A float that is floated above the water surface in the water level detection box, and that moves up and down in conjunction with water level fluctuations in the water level detection box;
The incineration plant according to claim 7, further comprising a valve that opens and closes a water supply pipe into the purification tank in conjunction with the vertical movement of the float. The incinerator has a structure in which a combustible material is introduced into the furnace from an upper surface opening thereof, and the upper surface opening is completely sealed with a lid structure after the combustible material is introduced. Item 4. The incineration plant according to Item 1. The incinerator is provided with a fire inlet on the side of the furnace, and a fire is injected into the furnace from the fire inlet, and after the flammable material in the furnace is ignited by the fire, the fire inlet is closed. 2. The incineration plant according to claim 1, wherein the incineration plant has a completely sealed structure. The incinerator comprises an upper surface opening-type housing composed of a side plate structure and a bottom plate structure, and a lid structure detachably attached to the upper surface opening,
The incineration plant according to claim 1, wherein the side plate structure, the bottom plate structure, and the lid structure have a water jacket structure having a flowing water passage in which cooling water flows. The gas transfer means,
Gas is disposed between one end of the smoke return pipe and a space above the water surface in the purification tank, and forcibly presses gas from the space above the water surface in the purification tank into the furnace of the incinerator via the smoke return pipe. 2. The incineration plant according to claim 1, further comprising a blower that is sent back in an indirect manner. The rectifier is provided between one end of the smoke return pipe and a space above the water surface in the purification tank as a means for preventing a waving phenomenon of the water surface in the purification tank. Incineration plant.

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