JP2009165969A - Polluted soil detoxification system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polluted soil detoxification system reduced in installation cost and running cost of a cleaning unit, in the case that decompression reduction heat decomposition dechlorination treatment is carried out by installing a decompression reduction heat decomposition apparatus is housed in the inside of a building. <P>SOLUTION: The polluted soil detoxification system is a system using a decompression reduction heat decomposition apparatus 24 installed in the inside of a building 115 and includes a leakage detection means for detecting occurrence of the hazardous state of pollutant leakage, a ventilation unit 111 for discharging a gas outside of the building 115, a cleaning unit 112 for cleaning the gas containing polluting substances and discharging the gas outside of the building 115, and a switching damper 113 for switching the ventilation unit 111 and the cleaning unit 112 in a manner that the gas in the building 115 is discharged via the ventilation unit 111 while detouring the cleaning unit 112 in the case no hazardous state of leakage occurs and the gas in the building 115 is discharged via the ventilation unit 111 and the cleaning unit 112 in the case the hazardous state of leakage occurs. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a system for detoxifying contaminated soil by decomposing contaminants by reduced pressure reduction heating.

  In recent years, soil contamination due to harmful substances has become apparent, and concerns about the impact on human health and the natural environment have expanded, and the need for technology for detoxifying contaminated soil has increased. In particular, since it is becoming difficult to secure a final disposal site for contaminated soil, an on-site contaminated soil detoxification technology that is compatible with various contaminated sites and is low-cost is required.

  In response to such demands, reduced pressure reduction thermal decomposition dechlorination treatment is known as a method for detoxifying organic chlorine-based contaminants such as dioxins and PCB (polychlorinated biphenyl). Reduced pressure reduction thermal decomposition dechlorination treatment is to detoxify by decomposing and decomposing organic chlorinated pollutants such as dioxins and PCBs in the contaminated soil by heat treating the contaminated soil in a reduced pressure atmosphere. Refers to processing. In addition, as a treatment system that shortens the treatment time and improves the treatment efficiency in the reduced pressure reduction thermal decomposition dechlorination treatment, an air dryer that dries and pulverizes the contaminated soil, and the particle size of the contaminated soil discharged from the air dryer. And a processing system provided with a reduced-pressure reduction thermal decomposition apparatus that reduces and decomposes contaminants by heating the classified contaminated soil (see, for example, Patent Document 1).

JP 2004-275993 A

  In such a processing system, it is required to take a leakage prevention measure so that dust generated in the reduced pressure reduction thermal decomposition apparatus does not leak outside the reduced pressure reduction thermal decomposition apparatus. As one of such measures for preventing leakage, it has been proposed that a reduced-pressure reduction thermal decomposition apparatus is accommodated in a building and a ventilation device and a purification device are provided in the building. Here, the ventilator ventilates the gas in the building by discharging the gas in the building that has become high temperature due to the heat generated by the reduced pressure reduction pyrolysis device to the outside of the building or taking in outside air from the outside of the building. It is a device that performs. Further, the purification device purifies the gas in the building containing the dust and discharges it outside the building when the dust in the reduced pressure reducing thermal decomposition device leaks outside the reduced pressure reducing thermal decomposition device.

  However, in the conventional treatment system, it is assumed that dust in the reduced pressure reduction thermal decomposition apparatus may leak out of the reduced pressure reduction thermal decomposition apparatus, and the gas inside the building is always outside the building via the purification device. Therefore, as the purification capacity of the purification apparatus, a large capacity corresponding to the entire volume of the building is required, which is a cause of increasing the installation cost of the purification apparatus. In particular, since the gas was always passed through the activated carbon and the filter constituting the purification device, a large amount of substances other than the contaminated dust was adsorbed by the activated carbon and the filter, which contributed to increase the replacement cost of the activated carbon and the filter. .

  The present invention has been made in view of the above, and in the case where the reduced pressure reduction thermal decomposition apparatus is accommodated in the building and the reduced pressure reduction thermal decomposition dechlorination treatment is performed, the installation cost and the running cost of the purification apparatus are reduced. The object is to provide a polluted soil detoxification system that can be reduced.

  In order to solve the above-mentioned problems and achieve the object, the present invention according to claim 1 decomposes the contaminant contained in the contaminated soil in the contaminated soil treatment apparatus accommodated inside the container. In the pollution soil detoxification system for detoxifying the contaminated soil, a leakage detection means for detecting the presence or absence of a leakage risk state that may cause the contaminant to leak to the outside of the contaminated soil treatment apparatus And ventilation means for discharging the gas in the container to the outside of the container, and purifying the gas in the container containing the contaminant leaked to the outside of the contaminated soil treatment device, The presence or absence of the leakage danger state is determined via the purification means for discharging to the outside and the leakage detection means, and when the leakage danger state is not established, the gas in the container passes through the purification means via the ventilation means. That's true The ventilating means and the purification means are switched so that the gas in the container is discharged outside the container through the ventilation means and the purifying means when it is exhausted out of the container and is in a leakage risk state. Switching means.

  According to a second aspect of the present invention, in the present invention according to the first aspect, the first processing capacity of the ventilation means when the leakage means is not in the leakage dangerous state is not When the required second processing capacity of the ventilation means is low, a ventilation means having a processing capacity equal to or higher than the first processing capacity is provided as the ventilation means, and the purification means is less than the first processing capacity. And a purifying means having a processing capacity equal to or greater than the second processing capacity.

  According to a third aspect of the present invention, in the present invention according to the first or second aspect, the present invention further includes a leakage prevention unit that prevents the contaminant from leaking outside the contaminated soil treatment apparatus, and the switching unit includes: The leakage prevention means is activated when the leakage is in danger.

  According to a fourth aspect of the present invention, in the present invention according to any one of the first to third aspects, the ventilation means includes an outside air inlet for taking outside air into the housing body, and the switching means is The ventilating means is switched so that the outside air port is opened when the leakage is not in danger and the outside air port is closed when the leakage is in danger.

  According to a fifth aspect of the present invention, in the present invention according to any one of the first to fourth aspects, the leakage detection means is a measurement means for measuring an internal pressure of the contaminated soil treatment apparatus. The switching means determines the presence or absence of the leakage danger state by comparing the pressure measured by the measurement means with a predetermined pressure. When the leakage means is not in the leakage danger state, the gas in the container causes the ventilation means to So that the gas in the container is exhausted out of the container through the ventilation means and the purification means when it is in a leaky state without passing through the purification means. The ventilation means and the purification means are switched.

  According to a sixth aspect of the present invention, in the present invention according to any one of the first to fifth aspects, the purification means is an activated carbon adsorption means for adsorbing the pollutant on the activated carbon, or the contamination. It includes a filter collecting means for collecting a substance through a filter.

  According to the first aspect of the present invention, the gas inside the container is not allowed to pass through the purifying means when it is not in a leakage danger state, so that the amount of gas passing through the purifying means can be reduced, and the filter of the purifying means can be replaced. Maintenance costs can be reduced. Also, the purification means can be used only when it is in danger of leakage, and in this case the contaminated soil treatment device is also stopped, etc., so that the ventilation volume can be reduced. This can reduce the installation cost of the purification means.

  According to the second aspect of the present invention, it is possible to reduce the installation cost of the purifying unit by setting the processing capability of the purifying unit to be less than the processing capability during normal operation of the ventilation unit.

  Further, according to the present invention, it is possible to effectively prevent the contaminant from leaking outside the contaminated soil treatment device by activating the leakage prevention means when it is in a leakage danger state. Can do.

  Moreover, according to this invention of Claim 4, since a switching means switches opening and closing of an external air opening, it can prevent that a dust leaks from the external air opening to the exterior of a building.

  Further, according to the fifth aspect of the present invention, when the internal pressure of the contaminated soil treatment apparatus becomes equal to or higher than a predetermined pressure, the purifier is automatically functioned. Therefore, based on the internal pressure of the contaminated soil treatment apparatus. Thus, the automatic switching control of the purification device can be performed.

  Moreover, according to this invention of Claim 6, by providing purification | cleaning means, such as activated carbon adsorption | suction means and a filter collection means, after purifying the gas containing dust to clean air, it discharges | emits outside the container. can do.

  Hereinafter, embodiments of a contaminated soil detoxification system according to the present invention will be described in detail with reference to the accompanying drawings. [I] First, the basic concept common to each embodiment was explained, then [II] the specific contents of each embodiment were explained, and [III] Finally, modifications to each embodiment were explained. To do. However, the present invention is not limited to each embodiment.

[I] Basic concept common to the embodiments First, the basic concept common to the embodiments will be described. The contaminated soil detoxification system according to each embodiment is intended to detoxify contaminated soil containing a contaminant.

  The target of installation of the contaminated soil detoxification system according to each embodiment is arbitrary. For example, it is installed in a factory site such as a chemical factory, a waste disposal site, an estuary, etc., and dioxins and PCBs contained in the contaminated soil It is possible to detoxify organic chlorinated pollutants.

  In each embodiment, it is assumed that an apparatus that may leak a contaminant is housed in the building. Examples of the pollutant include dust from the contaminated soil and the above-described vapor gas. Devices that may leak these contaminants include a dryer for drying the contaminated soil, A vacuum reduction heating apparatus that performs vacuum reduction heat treatment can be given. In each of the following embodiments, description will be made assuming that at least the reduced pressure reduction heating device is accommodated in the building, but the accommodation target can be arbitrarily changed. Further, in each of the following embodiments, the description will be made assuming that the contaminant to be purified is dust emitted from the contaminated soil.

  One of the features of the polluted soil detoxification system according to the present embodiment is roughly by decomposing the pollutants contained in the contaminated soil in the contaminated soil treatment apparatus accommodated inside the container. A leak detection system for detoxifying a contaminated soil that detoxifies the contaminated soil and determining whether there is a risk of leakage that may cause dust generated in the contaminated soil treatment device to leak out of the contaminated soil treatment device There is a means for performing switching control so that the gas in the container is exhausted to the outside of the container through the purification means only when there is a leakage risk state. This eliminates the need to allow the gas in the container to pass through the purification device when it is not in a leaky state, thereby reducing maintenance costs such as replacement of the filter of the purification means. Furthermore, the purification means only needs to be used when there is a risk of leakage. In this case, since the contaminated soil treatment apparatus is also stopped, the amount of ventilation can be reduced. And the installation cost of the purification means can be reduced.

[II] Specific Contents of Each Embodiment Next, specific contents of each embodiment according to the present invention will be described.

[Embodiment 1]
First, embodiments will be described. This form is a basic form for switching the purification device, and is a form in which a double hood is provided as a leakage preventing means. First, the overall configuration of the contaminated soil detoxification system and the outline of the contaminated soil detoxification process by the contaminated soil detoxification system will be described. Next, details of the configuration of the ventilation system of the building that houses the contaminated soil treatment apparatus, which is a feature of the contaminated soil detoxification system according to Embodiment 1, will be described.

(Configuration of contaminated soil detoxification system)
FIG. 1 is a schematic diagram of a contaminated soil detoxification system according to the present embodiment. As shown in FIG. 1, a contaminated soil detoxification system 1 includes a contaminated soil treatment system mainly including devices indicated by white blocks, a steam gas treatment system mainly including devices indicated by hatched blocks, And it is divided roughly into three systems of the dry distillation gas processing system including the apparatus mainly shown by the block of the grating | lattice. A heat exchanger 50, an activated carbon adsorption tank 60, a fuel supply device 70, exhaust heat utilization piping 80, and a control panel 90 are provided as devices commonly used in a plurality of systems or all of these systems. ing.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system)
The contaminated soil treatment system is a treatment system for treating the contaminated soil that has been input to the contaminated soil detoxification system 1. The soil hopper 20, the dryer 21, the blowing device 22, the conveying device 23, and the reduced pressure reduction heating device 24. And a cooling device 25.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system-soil hopper 20)
The soil hopper 20 is for supplying contaminated soil to the dryer 21. Since the specific configuration of the soil hopper 20 is known, the description thereof will be omitted. For example, the contaminated soil thrown into the soil hopper 20 by an operator is sent out at a predetermined delivery amount, and is passed through a transfer device (not shown). It is configured to supply to the dryer 21.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system-dryer 21)
The dryer 21 is for drying the contaminated soil supplied from the soil hopper 20. The specific configuration of the dryer 21 is arbitrary. For example, a rotary kiln type, a belt conveyor type, or a batch type dryer can be used. In the first embodiment, a rotary kiln type dryer is taken as an example. I will give you a description. FIG. 2 is a diagram showing an outline of the configuration of the dryer 21 according to the present embodiment. FIG. 2A is a side view of the entire dryer 21 (partially cut away), and FIG. FIG. 2B is an enlarged view of the region A in FIG. 2A, and FIG. 2C is an enlarged view of the region B in FIG. As shown in FIG. 2, the dryer 21 includes a combustion chamber 21a, a heating unit 21b, a rotary furnace 21c, and a drive unit 21d.

  The combustion chamber 21a is for ensuring the combustion space of the heating part 21b, and is provided so that the rotary furnace 21c may be covered. Moreover, the exhaust heat utilization piping 80 is connected to the combustion chamber 21a, and the exhaust heat from the reduced pressure reduction heating device 24 is introduced into the combustion chamber 21a. Moreover, the combustion chamber 21a is provided with the exhaust outlet 21e for discharging | emitting the gas inside the combustion chamber 21a.

  The heating unit 21b heats the contaminated soil in the dryer 21. Specifically, the fuel is burned inside the combustion chamber 21a, and the generated soil indirectly heats the contaminated soil inside the rotary furnace 21c through the furnace wall of the rotary furnace 21c.

  The rotary furnace 21c is a substantially cylindrical furnace that dries while moving the contaminated soil charged therein, and is rotatably installed so as to penetrate the inside of the combustion chamber 21a. A contaminated soil supply port 21f is provided at one end of the rotary furnace 21c, and a contaminated soil discharge port 21g is provided at the other end. A hood 21 h is provided around the supply port 21 f and the discharge port 21 g so that dust from the contaminated soil and vapor gas evaporated and volatilized from the contaminated soil do not leak out of the dryer 21. The hood 21h on the supply port 21f side is connected to a steam gas processing system via a steam gas pipe 30 described later. Further, a steam gas temperature measuring device (not shown) is provided in the vicinity of the connection portion with the steam gas piping 30, and the steam gas discharged from the inside of the rotary furnace 21 c to the steam gas piping 30 by the steam gas temperature measuring device. The temperature is measured. The hood 21 h on the discharge port 21 g side is connected to the transport device 23.

  Further, the rotary furnace 21c is arranged so that the major axis direction thereof has an inclination of a predetermined angle from the horizontal, and the contaminated soil inside moves from the supply port 21f to the discharge port 21g by the sliding due to rotation, and is discharged. . The rotary furnace 21c is heated from the outer peripheral surface side by the combustion gas or the like supplied into the combustion chamber 21a, and the contaminated soil inside the rotary furnace 21c is transferred by heat transferred from the outer periphery to the inner periphery of the rotary furnace 21c. Is heated.

  In addition, a temperature measuring device (not shown) is installed in the vicinity of the discharge port 21g inside the rotary furnace 21c. This temperature measuring instrument measures the temperature of the contaminated soil immediately before being discharged from the discharge port 21g, and outputs the measured data to the control panel 90.

  The drive unit 21d rotates the rotary furnace 21c at a predetermined rotational speed, and is connected to the rotary furnace 21c via a chain, a gear, or the like.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system-blowing device 22)
In FIG. 1, a blowing device 22 is for blowing cooling gas into a rotary furnace 21 c in the dryer 21. The blowing device 22 includes a blower fan (not shown) and a blower pipe (not shown). The blower fan blows the cooling gas. One end of the blowing pipe is connected to the blower fan, and the other end is connected to the rotary furnace 21 c of the dryer 21. As a result, the cooling gas blown from the blower fan passes through the blowing pipe and is blown toward the inside of the rotary furnace 21c to directly cool the contaminated soil. In addition, although the gas used as the cooling gas is arbitrary, for example, the outside air can be blown from the blower fan as the cooling gas.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system-transport device 23)
The conveyance device 23 is for conveying the contaminated soil discharged from the dryer 21 to the reduced pressure reduction heating device 24. Although the specific structure of the conveying apparatus 23 is arbitrary, for example, by using a hermetic belt conveyor or the like, the conveying device 23 can be conveyed without scattering contaminated soil to the outside.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system-reduced pressure reduction heating device 24)
The reduced pressure reduction heating device 24 is for detoxifying the contaminated soil dried by the dryer 21, and corresponds to the contaminated soil treatment device in the claims. As the reduced pressure reduction heating device 24, a rotary kiln heating furnace can be used. FIG. 3 is a diagram showing an outline of the configuration of the reduced pressure reduction heating device 24 according to the present embodiment, and FIG. 3A is a side view of the whole reduced pressure reduction device (partially cut away), FIG. 3 (b) is an enlarged view of region C in FIG. 3 (a), and FIG. 3 (c) is an enlarged view of region D in FIG. 3 (a). FIG. 4 is a side view showing the internal structure of the rotary furnace 24c of the reduced pressure reduction heating device 24 according to the present embodiment. As shown in FIG. 3, the reduced pressure reduction heating device 24 includes a combustion chamber 24a, a heating unit 24b, a rotary furnace 24c, and a drive unit 24d.

  The combustion chamber 24a is for ensuring the combustion space of the heating unit 24b, and is provided so as to cover the rotary furnace 24c. The combustion chamber 24a includes an exhaust outlet 24e for discharging the gas inside the combustion chamber 24a to the outside. An exhaust heat utilization pipe 80 (not shown in FIG. 3) is connected to the exhaust outlet 24e, and the combustion gas after heating the rotary furnace 24c passes through the exhaust heat utilization pipe 80 from the exhaust outlet 24e. And supplied to the dryer 21.

  The heating unit 24 b heats the contaminated soil in the reduced pressure reduction heating device 24. Specifically, fuel such as LPG is combusted inside the combustion chamber 24a, and the generated soil indirectly heats the contaminated soil inside the rotary furnace 24c through the furnace wall of the rotary furnace 24c.

  The rotary furnace 24c is a substantially cylindrical furnace that heats while moving the contaminated soil thrown into the rotary furnace 24c, and is rotatable substantially horizontally so as to penetrate the inside of the combustion chamber 24a. Is installed. The rotary furnace 24c is provided with a contaminated soil supply port 24f at one end and a contaminated soil discharge port 24g at the other end, and around the supply port 24f and the discharge port 24g, dust or A double hood 24h for preventing leakage of dry distillation gas is provided.

  The double hood 24h is for preventing dust generated in the reduced pressure reduction heating device 24 from leaking out of the reduced pressure reduction heating device 24, and corresponds to the leakage prevention means in the claims. As shown in FIGS. 3B and 3C, the duplex hood 24h includes a primary hood 24k, a secondary hood 24m, a local dust collector (not shown), and a suction device (not shown).

  The primary hood 24k prevents direct gas flow between the inside and the outside of the rotary furnace 24c. The primary hood 24k is provided slidably with respect to the rotary furnace 24c so as to cover the supply port 24f and the discharge port 24g, respectively. The primary hood 24k on the supply port 24f side is connected to a dry distillation gas pipe 40 (not shown in FIG. 3). The primary hood 24k on the discharge port 24g side is connected to a cooling device 25 (not shown in FIG. 3).

  The secondary hood 24m prevents direct gas flow between the inside and the outside of the primary hood 24k. The secondary hood 24m is slidably provided with respect to the rotary furnace 24c so as to cover the gap between the primary hood 24k and the rotary furnace 24c, and is connected to a local dust collector (not shown) via a pipe 24n. Yes.

  The local dust collector collects dust contained in the exhaust gas sucked from the inside of the secondary hood 24m by the suction force of the suction device.

  The suction device sucks dust discharged through the primary hood 24k and the secondary hood 24m. The above-described local dust collector is disposed between the suction device and the secondary hood 24m. When this suction device is operated, the reduced pressure reduction heating device 24 is in a negative pressure state, and the gas existing between the secondary hood 24m and the outer periphery of the rotary furnace 24c is sucked to the local dust collector by the suction device, After the dust contained in the sucked gas is removed by the local dust collector, the gas is discharged to the atmosphere.

  Further, as shown in FIG. 4, a spiral feed blade 24i is provided on the inner peripheral surface of the rotary furnace 24c, and the contaminated soil inside the rotary furnace 24c is fed with the rotation of the rotary furnace 24c. 24i moves from one end of the rotary furnace 24c to the other end and is discharged. A temperature measuring device 24j for measuring the temperature of contaminated soil is installed inside the rotary furnace 24c.

  Further, a pressure sensor (not shown) is installed in the vicinity of the supply port 24f and the discharge port 24g inside the rotary furnace 24c. This pressure sensor measures the pressure inside the rotary furnace 24c, and corresponds to the measuring means in the claims. Data measured by the pressure sensor is output to a switching unit 93 described later.

  In FIG. 3, the drive unit 24d rotates the rotary furnace 24c at a predetermined rotational speed, and is connected to the rotary furnace 24c via a chain, a gear, or the like.

  Here, since the gas inside the rotary furnace 24c is sucked into the dry distillation gas processing system, a reduced-pressure reducing atmosphere is maintained inside the rotary furnace 24c. The rotary furnace 24c is heated from the outer peripheral surface side by the combustion gas supplied into the combustion chamber 24a, and the heat transferred from the outer periphery to the inner periphery of the rotary furnace 24c The contaminated soil is heated. In this way, the contaminated soil is rendered harmless by being heated and maintained in a predetermined temperature range in the reduced-pressure reducing atmosphere.

(Configuration of contaminated soil detoxification system-contaminated soil treatment system-cooling device 25)
In FIG. 1, a cooling device 25 cools contaminated soil that has been rendered harmless by the reduced pressure reduction heating device 24. When dioxins are contained in the contaminated soil, even if once detoxified by being heated to a predetermined temperature in the reduced pressure reduction heating device 24 and then detoxified, it is left for a long time in a certain temperature range when the temperature drops thereafter. As a result, dioxins may be re-synthesized by using the metal in the contaminated soil as a catalyst. Therefore, the recombined dioxins can be prevented by rapidly cooling the detoxified contaminated soil by the cooling device 25.

(Configuration of contaminated soil detoxification system-steam gas treatment system)
In FIG. 1, the steam gas processing system is a processing system for processing steam gas containing moisture evaporated from the contaminated soil dried in the dryer 21, and includes a steam gas pipe 30, an emergency pipe 31, and a dust collector. 32, an activated carbon supply device 33, a heat retaining gas pipe 34, a dust collection dust pipe 35, a dust collection dust collecting machine 36, a steam gas cleaning tank 37, and a deodorization catalyst device 38. Here, “steam gas” in the description of the first embodiment refers to vapor evaporated from the contaminated soil dried in the dryer 21, gas such as PCB and odor that volatilized from the contaminated soil, and scattering from the contaminated soil. This refers to a gaseous substance that contains the dust and dioxins attached to the dust, or that has been partially removed or decomposed.

(Configuration of contaminated soil detoxification system-steam gas processing system-steam gas piping 30)
The steam gas pipe 30 is for introducing the steam gas into a device belonging to the above-described steam gas processing system in a predetermined order, and connects devices that perform continuous processing before and after.

(Configuration of contaminated soil detoxification system-steam gas treatment system-emergency piping 31)
The emergency pipe 31 is used when the temperature of the soil heated in the dryer 21 exceeds a predetermined temperature range, or when the steam gas discharged from the dryer 21 to the steam gas pipe 30 falls below a predetermined temperature. In an emergency, the vapor gas is not introduced into the dust collector 32 but is introduced into a high-temperature dust collector 41 described later in the dry distillation gas processing system.

(Configuration of contaminated soil detoxification system-steam gas treatment system-dust collector 32)
The dust collector 32 is for collecting dust contained in the vapor gas. The dust collector 32 is connected to the dryer 21 via the steam gas pipe 30, and the steam gas generated inside the dryer 21 is introduced into the dust collector 32. In addition, the dust collector 32 is connected to the dust collector 36 through the dust collector pipe 35, and the dust collected by the dust collector 32 passes through the dust collector pipe 35. It is conveyed to.

(Configuration of contaminated soil detoxification system-steam gas processing system-activated carbon supply device 33)
The activated carbon supply device 33 is for blowing a predetermined amount of activated carbon into the dust collector 32, and is connected to the steam gas pipe 30 on the entrance side of the dust collector 32. The dust collection rate can be increased by adsorbing the dust contained in the vapor gas to the activated carbon and collecting the activated carbon on which the dust is adsorbed by the dust collector 32.

(Configuration of contaminated soil detoxification system-steam gas treatment system-insulated gas piping 34)
In order to keep the dust collector 32 at a predetermined temperature or higher, the heat insulation gas pipe 34 supplies a heat insulation gas to a heat insulation jacket (not shown) covering the dust collector 32 and convects the dust collector 32.

(Configuration of contaminated soil detoxification system-steam gas treatment system-dust collection unit 36)
The dust collecting dust collecting machine 36 is for collecting dust conveyed by the dust collecting dust pipe 35, and for example, a bag filter type dust collecting machine 32 is used.

(Configuration of contaminated soil detoxification system-steam gas treatment system-steam gas cleaning tank 37)
The steam gas cleaning tank 37 is for removing dust, dioxin and the like contained in a trace amount in the steam gas that has passed through the dust collector 32. Since dioxin is adsorbed to the dust, the dioxin can be removed from the steam gas by removing the dust with the steam gas cleaning tank 37.

(Configuration of contaminated soil detoxification system-steam gas treatment system-deodorization catalyst device 38)
The deodorization catalyst device 38 is for removing a trace amount of odor, PCB, and the like contained in the steam gas that has passed through the steam gas cleaning tank 37. The deodorization catalyst device 38 oxidizes odor components, PCB, and the like contained in the vapor gas by bringing the vapor gas heated to a predetermined temperature or more into contact with the catalyst.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system)
In FIG. 1, a dry distillation gas treatment system is a treatment system for treating dry distillation gas containing organic chlorine-based contaminants such as dioxins and PCBs separated from contaminated soil in the course of reduced pressure reduction heat treatment. A gas pipe 40, a high-temperature dust collector 41, a slaked lime supply device 42, a granulator 43, a bypass pipe 44, an exhaust gas oxidation device 45, an exhaust gas cooling device 46, a dust collector 47, and a desulfurization device 48 are provided.

(Configuration of decontaminated soil decontamination system-dry distillation gas treatment system-dry distillation gas piping 40)
The dry distillation gas pipe 40 is for introducing the dry distillation gas into the devices belonging to the above-described dry distillation gas processing system in a predetermined order, and connects the devices that perform continuous processing before and after. Further, one end of the emergency pipe 31 in the steam gas processing system is connected to the dry distillation gas pipe 40 between the vacuum reduction heating device 24 and the high temperature dust collector 41 in FIG. To be introduced.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-high temperature dust collector 41)
The high-temperature dust collector 41 is for collecting dust contained in the high-temperature dry distillation gas. The high-temperature dust collector 41 is connected to the rotary furnace 24 c of the reduced pressure reduction heating device 24 through the dry distillation gas pipe 40 and is connected to the dry distillation gas pipe 40. Is connected to the exhaust gas oxidation device 45. The dry distillation gas separated from the contaminated soil inside the rotary furnace 24c is introduced into the high-temperature dust collector 41 via the dry distillation gas pipe 40, and after dust contained in the dry distillation gas is removed, the dry distillation gas is supplied to the exhaust gas oxidation device 45. And discharged.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-slaked lime supply device 42)
The slaked lime supply device 42 throws slaked lime into the dry distillation gas in order to neutralize the acidic gas contained in the dry distillation gas.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-granulator 43)
The granulator 43 is for forming the dust collected by the high-temperature dust collector 41 as granules having a predetermined size. The dust collected by the high temperature dust collector 41 is kneaded with a binder and water in a kneader (not shown), and then formed into granules by the granulator 43 and put into the reduced pressure reduction heating device 24.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-bypass piping 44)
The bypass pipe 44 does not allow the dry distillation gas to be introduced into the high temperature dust collector 41 when the temperature of the dry distillation gas before introduction into the high temperature dust collector 41 is equal to or lower than a predetermined temperature. 45 is introduced. Specifically, one end portion of the bypass pipe 44 is connected to the one end of the bypass pipe 44 via a switching damper 49 (shown only in FIG. 5) on the side of the reduced pressure reduction heating apparatus 24 from the connection portion between the slaked lime supply apparatus 42 and the dry distillation gas pipe 40. A dry distillation gas pipe 40 is connected. The other end of the bypass pipe 44 is connected to the exhaust gas oxidation device 45 through the dry distillation gas pipe 40.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-exhaust gas oxidation device 45)
The exhaust gas oxidizer 45 performs high-temperature incineration processing of organic chlorine-based contaminants such as dioxins and PCBs contained in the dry distillation gas that has passed through the high-temperature dust collector 41.

(Configuration of decontaminated soil decontamination system-dry distillation gas treatment system-exhaust gas cooling device 46)
The exhaust gas cooling device 46 is for cooling the dry distillation gas that has passed through the heat exchanger 50. The inflow side of the dry distillation gas in the exhaust gas cooling device 46 is connected to the heat exchanger 50 through the dry distillation gas pipe 40, and the outflow side is connected to the dust collector 47 through the dry distillation gas pipe 40.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-dust collector 47)
The dust collector 47 is for collecting dust remaining in a trace amount in the dry distillation gas that has passed through the exhaust gas cooling device 46. The inflow side of the dry distillation gas in the dust collector 47 is connected to the exhaust gas cooling device 46 through the dry distillation gas piping 40, and the outflow side is connected to the desulfurization device 48 through the dry distillation gas piping 40.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-desulfurization equipment 48)
The desulfurization device 48 is for removing sulfur oxides and nitrogen oxides contained in the dry distillation gas that has passed through the dust collector 47. The inflow side of the dry distillation gas in the desulfurization device 48 is connected to the dust collector 47 through the dry distillation gas pipe 40, and the outflow side is connected to the activated carbon adsorption tank 60 through the dry distillation gas pipe 40.

(Configuration of decontaminated soil decontamination system-dry distillation gas treatment system-heat exchanger 50)
The heat exchanger 50 exchanges heat between the dry distillation gas that has passed through the exhaust gas oxidizer 45 in the dry distillation gas processing system and the steam gas that has passed through the steam gas cleaning tank 37 in the steam gas processing system.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-activated carbon adsorption tank 60)
In FIG. 1, in the activated carbon adsorption tank 60, a small amount of dust, odor, etc. remains in the vapor gas that has passed through the deodorization catalyst device 38 in the vapor gas treatment system and the dry distillation gas that has passed through the desulfurization device 48 in the dry distillation gas treatment system. If so, it is adsorbed and the purified gas is exhausted from the chimney 100 to the outside.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-fuel supply device 70)
The fuel supply device 70 is for supplying fuel and auxiliary combustion air to the dryer 21, the reduced pressure reduction heating device 24, and the exhaust gas oxidation device 45.

(Configuration of contaminated soil detoxification system-dry distillation gas treatment system-exhaust heat utilization piping 80)
The exhaust heat utilization pipe 80 is for allowing the exhaust heat of the reduced pressure reduction heating device 24 to be utilized in the dryer 21. Specifically, one end of the exhaust heat utilization pipe 80 is connected to an exhaust fan provided in the combustion chamber 24 a of the reduced pressure reduction heating device 24, and the other end is connected to the combustion chamber 21 a of the dryer 21. ing.

(Configuration of contaminated soil detoxification system-control panel 90)
The control panel 90 is for controlling the operation of the contaminated soil detoxification system 1. FIG. 5 is a block diagram functionally conceptually showing the electrical configuration of the control panel 90 according to the present embodiment. As shown in FIG. 5, the control panel 90 includes a dryer control unit 91, a reduced pressure reduction heating device control unit 92, a switching unit 93, a cooling device control unit 94, a steam gas processing control unit 95, a dry distillation gas processing control unit 96, An input unit 97 and a storage unit 98 are provided.

  The dryer control unit 91 controls the dryer 21 and the blowing device 22. The reduced pressure reduction heating device control unit 92 controls the reduced pressure reduction heating device 24 and a suction device described later. The switching unit 93 performs switching control of the switching damper 113 described later, and switching control for opening and closing of the outside air port 111e provided in the ventilation device 111. The switching unit 93 corresponds to the switching unit in the claims. The details of the switching unit 93 will be described later in the description of the ventilation process. The cooling device control unit 94 controls the cooling device 25. The steam gas processing control unit 95 performs switching control of the switching damper 39 for the emergency pipe 31 of the steam gas processing system. The dry distillation gas treatment control unit 96 performs switching control of the switching damper 49 for the bypass piping 44 of the dry distillation gas treatment system. The input unit 97 is for causing the control panel 90 to input operation information used for control by the control panel 90, such as properties such as moisture content of the contaminated soil and the input amount. The storage unit 98 stores the operation information input to the control panel 90 via the input unit 97.

  Although the specific configuration of the control panel 90 is arbitrary, for example, a control program such as an OS (Operating System), a program defining various processing procedures, an internal memory for storing necessary data, and these And a CPU (Central Processing Unit) for executing the program.

(Processing flow by the pollution soil detoxification system)
Next, an outline of the contaminated soil detoxification process performed by the contaminated soil detoxification system 1 will be described. FIG. 6 is a flowchart showing the flow of the contaminated soil detoxification process according to the present embodiment. The contaminated soil detoxification system 1 separates the contaminated soil from the contaminated soil during the treatment of the vapor gas evaporated from the contaminated soil in the dryer 21 and the reduced pressure reduction heat treatment of the contaminated soil in the reduced pressure reduction heating device 24. The process of the dry distillation gas is performed, but the description is omitted here.

(Flow of treatment by contaminated soil detoxification system-contaminated soil)
First, the processing flow of contaminated soil will be described. The contaminated soil thrown into the soil hopper 20 is transferred to the dryer 21 by the transfer device (step SA-1). In the dryer 21, the temperature of the contaminated soil and the temperature of the vapor gas discharged from the dryer 21 are maintained within a predetermined temperature range, and the contaminated soil is dried (step SA-2). The contaminated soil transferred to the discharge port 21g through the rotary furnace 21c is discharged from the discharge port 21g (step SA-3).

  The contaminated soil discharged from the dryer 21 is transported to the reduced pressure reduction heating device 24 by the transport device 23 (step SA-4). The contaminated soil transported to the reduced pressure reduction heating device 24 is introduced into the rotary furnace 24c from the supply port 24f (step SA-5). The contaminated soil charged into the rotary furnace 24c is heated from the combustion gas or the like in the combustion chamber 24a through the furnace wall of the rotary furnace 24c (step SA-6). As a result, organic chlorine-based contaminants such as dioxins and PCBs contained in the contaminated soil are separated from the contaminated soil and decomposed by reduced-pressure reduction heating. At this time, the dry distillation gas containing dioxins separated from the contaminated soil and organic chlorine-based contaminants such as PCB is discharged from the double hood 24h on the supply port 24f side of the rotary furnace 24c to the dry distillation gas pipe 40. The contaminated soil that has moved through the rotary furnace 24c to the discharge port 24g is discharged from the discharge port 24g (step SA-7).

  The contaminated soil discharged from the rotary furnace 24c of the reduced pressure reduction heating device 24 is put into the rotating body of the cooling device 25 (step SA-8). The contaminated soil thrown into the rotating body from the supply port of the rotating body is indirectly cooled through the wall surface of the rotating body by cooling water discharged to the outer peripheral surface of the rotating body (step SA-9). . If the cooling device control unit 94 determines that the cooling capacity of the cooling device 25 is reduced based on the temperature rise of the contaminated soil inside the rotating body (step SA-10, Yes), the water spray The apparatus sprays the cooling water on the contaminated soil, and directly cools the contaminated soil (step SA-11). The contaminated soil that has moved inside the rotating body to the discharge port is discharged from the discharge port (step SA-12). The discharged contaminated soil is carried out by a predetermined carrying-out means as detoxified soil. This completes the contaminated soil detoxification process.

(Configuration of ventilation system 110)
Next, the structure of the ventilation system 110 for ventilating the building 115 will be described. FIG. 7 is a schematic diagram of the ventilation system 110 in the normal building 115 according to the first embodiment, and FIG. 8 is a schematic diagram of the ventilation system 110 in the emergency building 115 according to the first embodiment. Here, at least the reduced pressure reduction heating device 24 is accommodated in the building 115, and a ventilation system 110 is provided to ventilate the building 115.

  In the following description, the normal time is when the inside of the building 115 is not in a leakage risk state (when dust leakage can be normally prevented), and the emergency time is when the inside of the building 115 is in a leakage risk state ( When there is a possibility that dust leakage may not be prevented normally). The normality of prevention of dust leakage is determined based on the pressure of the rotary furnace 24c of the reduced pressure reduction heating device 24 in the first embodiment. That is, when the pressure is less than or equal to a predetermined pressure, it is determined that there is no possibility of dust leakage, and when the pressure exceeds the predetermined pressure, it is determined that there is a possibility of dust leakage.

  As shown in FIGS. 7 and 8, the ventilation system 110 includes a ventilation device 111, a purification device 112, and a switching damper 113.

(Configuration of ventilation device 111)
The ventilation device 111 ventilates the building 115 by discharging the gas in the building 115 to the outside of the building 115 or taking outside air into the building 115, and corresponds to the ventilation means in the claims. ing. The ventilation device 111 includes an air passage 111a, an air passage 111b, an exhaust passage 111c, a blower 111d, and an outside air port 111e.

  The air passage 111a sends the gas in the building 115 from the inside of the building 115 to the blower 111d or the purification device 112. Specifically, the air passage 111 a is configured as a long hollow pipe line extending from a position near the ceiling inside the building 115 to the blower 111 d outside the building 115, and an opening formed inside the building 115. Air inside the building 115 is sucked from the end 111f, and the sucked air is introduced into the blower 111d outside the building 115. The ventilation path 111b is a hollow pipe that introduces the air blown from the blower 111d into the purification device 112 or the exhaust path 111c via the switching damper 113. The exhaust path 111 c is a hollow duct that discharges air introduced from the ventilation path 111 b via the switching damper 113 toward the outside of the building 115. The blower 111d ventilates the inside of the building 115 by blowing the gas in the building 115 through the air passage 111a. The outside air port 111e is an opening for taking outside air into the building 115, and is installed on the wall side of the building 115 or the like. The outside air port 111e is provided with an open / close shutter 111g, and the outside air port 111e can be opened and closed by controlling the opening / closing of the open / close shutter 111g. The opening / closing of the opening / closing shutter 111g is controlled by the switching unit 93. Details of the switching unit 93 will be described later. The opening / closing shutter 111g corresponds to switching means in the claims.

  Here, the processing capability of the ventilator 111 is determined based on the necessary capability in the normal state. That is, during normal operation, since the reduced-temperature reduction heating device 24 is operated, the temperature rise of the gas in the building 115 is relatively large, whereas in an emergency, the operation of the reduced-pressure reduction heating device 24 is stopped. Since the temperature rise of the gas in the building 115 is relatively small, the normal processing capacity is larger than the emergency processing capacity. Therefore, here, the processing capacity of the ventilator 111 is determined so as to satisfy the required capacity under normal conditions, which is the larger processing capacity. However, when the processing capability of the ventilator 111 is set as a necessary capability at the normal time as described above, a part of the function of the ventilator 111 may be stopped because the processing capability of the ventilator 111 is surplus in an emergency. For example, a plurality of blowers 111d may be disposed, and ventilation may be performed by operating all the blowers 111d during normal operation, and ventilation may be performed by operating only some of the blowers 111d during an emergency. The normal processing capability corresponds to the first processing capability in the claims, and the emergency processing capability corresponds to the second processing capability in the claims.

(Configuration of purification device 112)
The purification device 112 purifies the gas in the building 115 containing dust leaked outside the reduced pressure reduction heating device 24 and discharges it to the outside of the building 115, and corresponds to the purification means in the claims. Yes. The purification device 112 includes an activated carbon adsorption tank 112a, a HEPA filter 112b, and an air passage 112c. The activated carbon adsorption tank 112a adsorbs dust on activated carbon, and corresponds to the activated carbon adsorption means in the claims. The HEPA filter 112b collects dust through a filter and corresponds to the filter collecting means in the claims. The ventilation path 112c is a hollow pipe line that is disposed between the activated carbon adsorption tank 112a and the HEPA filter 112b and introduces air discharged from the activated carbon adsorption tank 112a into the HEPA filter 112b.

  Here, the processing capacity of the purification device 112 is determined based on the necessary capacity in an emergency. That is, at the normal time, since the contaminated dust does not leak into the building 115, the purification by the purification device 112 is unnecessary, and the purification device 112 only needs to be used in an emergency. What is necessary is just to be equal to or greater than the processing capacity of the ventilation device 111. For example, when the three blowers 111d of the ventilation system 110 are provided, only one purification device 112 having a processing capacity equivalent to the blowing ability of the blower 111d may be provided.

(Configuration of switching damper 113)
The switching damper 113 switches between the ventilation device 111 and the purification device 112, and corresponds to the switching means in the claims. Specifically, the switching damper 113 is a ventilation path switching unit disposed in the ventilation path 111b from the blower 111d to the purification device 112, and the air blown from the blower 111d is sent to either the purification device 112 or the exhaust path 111c. Selective introduction to either.

(Gas ventilation treatment)
Next, the flow of the gas ventilation process will be described. FIG. 9 is a flowchart of the gas ventilation process according to the first embodiment. First, ventilation in the building 115 is performed as preparation before the reduced pressure reduction heat treatment. That is, the switching unit 93 of the control panel 90 opens the open / close shutter 111g of the outside air port 111e in order to take outside air into the building 115 when the start of the ventilation process is instructed by an arbitrary method (step SB- 1). Then, the switching unit 93 controls the switching damper 113 so that the gas in the building 115 is discharged outside the building 115 only through the ventilation device 111 without passing through the purification device 112 (step SB-2). ).

  After that, the switching unit 93 starts the pressure reduction heating treatment of the contaminated soil by the vacuum reduction heating device 24 (step SB-3), and at the same time, is installed in the vicinity of the supply port 24f and the discharge port 24g of the vacuum reduction heating device 24. An output from the sensor is acquired at a predetermined cycle (step SB-4), and the acquired pressure value is compared with a reference pressure value stored in the storage unit 98 (step SB-5).

  Here, when the acquired pressure value is lower than the reference value (step SB-5, Yes), the switching unit 93 determines that it is normal, and continues the ventilation process and the reduced pressure reduction heating process (step SB). -6). Note that (Step SB-4) to (Step SB-6) are repeatedly performed until the reduced pressure reduction heat treatment is completed.

  On the other hand, when the acquired pressure value is equal to or higher than the reference value (step SB-5, No), the switching unit 93 determines that it is an emergency and immediately stops the reduced pressure reduction heating process (step SB-7). ), The suction device is operated (step SB-8). The suction device sucks the gas existing between the secondary hood 24m and the outer periphery of the rotary furnace 24c through the local dust collector, and collects the dust contained in the gas by the local dust collector.

  Further, the switching unit 93 closes the open / close shutter 111g of the outside air port 111e to prevent dust from leaking to the outside of the building 115 (step SB-9), and causes the ventilation device 111 and the purification device 112 to remove the gas in the building 115. The switching unit 93 is controlled so as to be discharged to the outside of the building 115 (step SB-10). Thereafter, when the administrator cancels the abnormal state and instructs the ventilation process to be resumed by an arbitrary method, the switching unit 93 proceeds to step SB-1 and resumes the ventilation process. However, the ventilation process may be resumed automatically. For example, a sensor for detecting dioxins, PCBs, etc. is provided in the building 115, and the dioxins, PCBs, etc. have passed for a certain period of time. If it is not detected, it may be determined that the normal state has been restored, and the process may automatically proceed to step SB-1.

(Effect of Embodiment 1)
As described above, according to the first embodiment, since it is not necessary to always use the purification device 112, it is possible to reduce maintenance management costs such as filter replacement of the purification device 112. In addition, the purification device 112 only needs to be used in an emergency. In this case, since the reduced pressure reduction heating device 24 is also stopped and the like, the ventilation amount can be reduced. The installation cost of the purification device 112 can be reduced.

  Moreover, it can prevent that the switching part 93 leaks from the duplex hood 24h of the pressure reduction reduction heating apparatus 24 by starting the local dust collector of the duplex hood 24h in emergency.

  Further, the switching unit 93 switches the open / close shutter 111g so that the outside air port 111e is opened during normal operation and the outside air port 111e is closed in an emergency, so that dust is leaked from the outside air port 111e to the outside of the building 115. Can be prevented.

  Further, the switching damper 113 determines whether or not it is normal by comparing the pressure measured by the pressure sensor for measuring the internal pressure of the reduced pressure reduction heating device 24 with a predetermined pressure. Thereby, the switching damper 113 and the opening / closing shutter 111g can be automatically controlled.

(Embodiment 2)
Next, a second embodiment will be described. In the second embodiment, an air barrier is provided instead of the suction device provided in the first embodiment. The configuration of the second embodiment is substantially the same as the configuration of the first embodiment except where otherwise specified, and the configuration substantially the same as the configuration of the first embodiment is used in the first embodiment. The same reference numerals are given as necessary, and the description thereof is omitted.

(Configuration of air barrier)
FIG. 10 is a diagram showing an outline of the configuration of the reduced pressure reduction heating apparatus according to the second embodiment. FIG. 10 (a) is a side view of the entire reduced pressure reduction apparatus (partially cut away), FIG. 10 (b) is an enlarged view of region E in FIG. 10 (a), and FIG. 10 (c) is an enlarged view of region F in FIG. 10 (a). The reduced pressure reduction heating device 24 includes an air barrier 114. This air barrier 114 prevents the leakage of dust to the outside of the reduced pressure reduction heating device 24 by pressurizing the leaked portion of the dust generated in the reduced pressure reduction heating device 24, and prevents leakage in the claims. Corresponds to the means.

  Specifically, the air barrier 114 includes a pressure tank 114a, an air pipe 114b, and an injection port 114c.

  The pressure tank 114a stores compressed air in a sealed container, and is connected to the air pipe 114b. The specific shape, size, and number of the pressure tanks 114a are arbitrary, and are determined in consideration of the processing capacity of the reduced pressure reduction heating device 24 and the like.

  The air pipe 114b is a hollow pipe for sending the compressed air stored in the pressure tank 114a to the injection port 114c, and is disposed between the pressure tank 114a and the injection port 114c. Although the connection method of the pressure tank 114a and the air pipe 114b is arbitrary, for example, a plurality of air pipes 114b may be connected to one pressure tank 114a.

  The injection port 114c is an opening for injecting compressed air introduced from the pressure tank 114a through the air pipe 114b to the outside. The injection port 114c is disposed in the vicinity of the supply port 24f and the discharge port 24g of the rotary furnace 24c in the duplex hood 24h, and the supply port 24f and the exhaust port are discharged by compressed air injected from the injection port 114c. The open end of the outlet 24g is blocked. The injection port 114c is provided with an opening / closing plug (not shown), and the injection port 114c can be opened / closed by opening / closing the opening / closing plug. The opening / closing of the opening / closing plug is controlled by the switching unit 93. Details of the switching unit 93 will be described later.

(Gas ventilation treatment)
Next, the flow of the gas ventilation process will be described. FIG. 11 is a flowchart of a gas ventilation process according to the second embodiment. However, steps other than step SC-8 are the same as the steps assigned the same process name in FIG. When the acquired pressure value becomes equal to or higher than the reference value (No at Step SC-5), the switching unit 93 of the control panel 90 stops the reduced pressure reduction heating process (Step SC-7) and also sends compressed air from the air barrier 114. The stopper is controlled so as to be injected (step SC-8). This air barrier 114 blocks the open ends of the supply port 24f and the discharge port 24g by the jetted compressed air inside the duplex hood 24h, and prevents dust from leaking outside from the supply port 24f and the discharge port 24g. To do.

(Effect of Embodiment 2)
As described above, according to the second embodiment, in addition to the effects substantially the same as those of the first embodiment, the switching unit 93 opens the open / close plug of the air barrier 114 in an emergency, so that dust is reduced in the reduced pressure reduction heating device 24. Leakage from the duplex hood 24h can be prevented.

[III] Modifications to Each Embodiment While each embodiment according to the present invention has been described above, the specific configuration and means of the present invention are the same as the technical idea of each invention described in the claims. Modifications and improvements can be arbitrarily made within the range. Hereinafter, such a modification will be described.

(About problems to be solved and effects of the invention)
First, the problems to be solved by the invention and the effects of the invention are not limited to the above-described contents, and the present invention solves the problems not described above or has the effects not described above. There are also cases where only some of the described problems are solved or only some of the described effects are achieved.

(About the accommodation object)
In the first and second embodiments, the gas ventilation system 110 in the building 115 that houses the reduced-pressure reduction heating device 24 has been described in the above-described embodiment, but the gas ventilation in the building 115 that houses the dryer 21 is described. The system 110 may be used.

(Judgment of the presence or absence of leakage risk)
Various determination methods other than the determination based on the pressure of the rotary furnace 24c of the reduced pressure reduction heating device 24 can be adopted as the determination method of the presence or absence of the leakage risk state. For example, dioxins or PCBs are detected in the building 115. The sensor may be provided, and when dioxins, PCB, or the like is detected by this sensor, it may be determined that there is an emergency.

  The contaminated soil detoxification system according to the present invention can be applied to a system and method for detoxifying contaminated soil by subjecting a contaminant to reduced pressure reduction heating, and in particular, a reduced pressure reduction heat treatment is performed by accommodating a reduced pressure reduction heating device inside the building. This is useful for reducing the installation cost of the purification device.

It is the schematic of the contaminated soil detoxification system which concerns on Embodiment 1 of this invention. It is the figure which showed the outline of the structure of a dryer, FIG.2 (a) is a side view of the whole dryer, FIG.2 (b) is an enlarged view of the area | region A in Fig.2 (a), FIG.2 (c) FIG. 3 is an enlarged view of a region B in FIG. It is the figure which showed the outline of the structure of a pressure reduction heating apparatus, FIG.3 (a) is a side view of the whole pressure reduction reduction apparatus, FIG.3 (b) is an enlarged view of the area | region C in FIG.3 (a), FIG. (C) is an enlarged view of a region D in FIG. It is a side view showing the internal structure of the rotary furnace of a pressure reduction heating apparatus. It is the block diagram which showed the electrical structure of the control panel functionally conceptually. It is a flowchart of a contaminated soil detoxification process. It is the schematic of the ventilation system in a building at the time of normal. It is the schematic of the ventilation system in a building in emergency. It is a flowchart of the ventilation process of gas. It is the figure which showed the outline of the structure of the pressure reduction reduction heating apparatus which concerns on Embodiment 2, FIG. 10 (a) is a side view of the whole pressure reduction reduction apparatus, FIG.10 (b) is the area | region E in FIG.10 (a). FIG. 10C is an enlarged view of a region F in FIG. It is the flowchart which showed the flow of the ventilation process of gas.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contaminated soil detoxification system 20 Soil hopper 21 Dryer 21a, 24a Combustion chamber 21b, 24b Heating part 21c, 24c Rotary furnace 21d, 24d Drive part 21e, 24e Exhaust outlet 21f, 24f Supply port 21g, 24g Exhaust port 21h Hood 22 Blowing device 23 Conveying device 24 Reduced pressure reduction heating device 24h Duplex hood 24i Feed blade 24j Temperature measuring device 24k Primary hood 24m Secondary hood 24n Piping 25 Cooling device 30 Steam gas piping 31 Emergency piping 32, 47 Dust collector 33 Activated carbon supply device 34 Insulation Gas piping 35 Dust collection dust piping 36 Dust collection dust recovery machine 37 Steam gas cleaning tank 38 Deodorization catalyst device 39 Switching damper 40 Dry distillation gas piping 41 High temperature dust collector 42 Slaked lime supply device 43 Granulator 44 Bypass piping 45 Exhaust gas oxidation device 46 Exhaust gas Cooling device 48 Desulfurization device 49 Switching damper 50 Heat exchanger 60, 112a Activated carbon adsorption tank 70 Fuel supply device 80 Waste heat utilization piping 90 Control panel 91 Dryer control unit 92 Decompression reduction heating device control unit 93 Switching unit 94 Cooling device control unit 95 Steam gas processing control unit 96 Dry distillation gas processing control unit 97 Input unit 98 Storage unit 100 Chimney 110 Ventilation system 111 Ventilation device 111a, 111b, 112c Ventilation path 111c Exhaust path 111d Blower 111e Open air port 111f Open end 112 Purifier 112b HEPA Filter 113 Switching damper 114 Air barrier 114a Pressure tank 114b Air pipe 114c Injection port 115 Building

Claims (6)

A contaminated soil detoxification system that detoxifies the contaminated soil by decomposing the pollutants contained in the contaminated soil in the contaminated soil treatment device housed in the container,
Leakage detection means for detecting the presence or absence of a leakage danger state that may cause the contaminant to leak outside the contaminated soil treatment device;
Ventilation means for discharging the gas in the container to the outside of the container;
Purification means for purifying the gas contained in the container containing the pollutant leaked to the outside of the contaminated soil treatment apparatus and discharging the gas to the outside of the container;
The presence or absence of the risk of leakage is determined via the leakage detection means, and when the leakage is not dangerous, the gas in the container is discharged outside the container without passing through the purification means via the ventilation means. Switching means for switching between the ventilation means and the purification means so that the gas in the container is exhausted to the outside of the container through the ventilation means and the purification means when in the leakage danger state;
Contaminated soil detoxification system characterized by comprising: When the required second processing capacity of the ventilation means when not in the leakage risk state is lower than the required first processing capacity of the ventilation means when in the leakage risk state,
As the ventilation means, a ventilation means having a processing capacity equal to or higher than the first processing capacity is provided,
As the purifying means, a purifying means having a processing capacity less than the first processing capacity and having a processing capacity equal to or higher than the second processing capacity is provided.
The polluted soil detoxification system according to claim 1. Leakage prevention means for preventing the pollutant from leaking outside the contaminated soil treatment apparatus,
The switching means activates the leakage prevention means when the leakage danger state;
The contaminated soil detoxification system according to claim 1 or 2. The ventilating means includes an outside air port for taking outside air into the containing body,
The switching means switches the ventilation means so as to open the outside air port when not in the leakage danger state and close the outside air mouth when the leakage danger state,
The contaminated soil detoxification system according to any one of claims 1 to 3. The leakage detection means is a measurement means for measuring an internal pressure of the contaminated soil treatment apparatus,
The switching means determines the presence or absence of the leakage danger state by comparing the pressure measured by the measurement means with a predetermined pressure. When the leakage means is not in the leakage danger state, the gas in the container passes through the ventilation means. So that the gas in the container is exhausted to the outside of the container through the ventilation means and the purification means when it is exhausted out of the container without passing through the purification means and is in a leaky state. Switching between the ventilation means and the purification means;
The polluted soil detoxification system according to any one of claims 1 to 4. The purification means includes activated carbon adsorption means for adsorbing the pollutant on activated carbon, or filter collection means for collecting the contaminant through a filter,
The polluted soil detoxification system according to any one of claims 1 to 5.

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