JP2005288434A - Detoxifying treatment method for heavy metal-containing substance, apparatus therefor and the system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detoxifying treatment method for a heavy metal-containing substance capable of efficiently performing chlorination of heavy metals by sufficiently contacting the heavy metals with a chlorine based gas, suppressing remaining of the heavy metals after treatment to the minimum while maintaining removal efficiency of the heavy metals to a high degree, reducing a cost by suppressing feeding of thermal energy and reducing load to a treatment facility of exhaust gas containing the chlorine used for the chlorination, an apparatus therefor and the system. <P>SOLUTION: In the detoxifying treatment system for the heavy metal-containing substance, after the chlorine based exhaust gas is introduced from a furnace bottom of a fluidization furnace 40 for storing incineration ash 30 containing the heavy metals, and the heavy metals are chlorinated while fluidizing, the incineration ash containing the chlorinated heavy metals is introduced into a rotary kiln 10 and is heated to perform volatilization/separation of the heavy metals. The chlorine based exhaust gas is made to the chlorine based exhaust gas drawn from a re-combustion chamber 21 of the exhaust gas treatment facility at a latter stage or the chlorine based exhaust gas drawn from a downstream side of the re-combustion chamber 21 and an upstream side of an air pre-heater 22. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a technique for detoxifying heavy metals contained in contaminated soil, incinerated ash, fly ash, etc., and in particular detoxifying heavy metal-containing substances that are detoxified by heating after chlorinating heavy metals. The present invention relates to a processing method and apparatus, and the system.

Various types of heavy metals are contained in incineration ash and fly ash generated by incineration of general waste and industrial waste. Incinerators that do not have heavy metal treatment facilities may leak heavy metal-containing substances into the atmosphere, soil, and groundwater. In addition, there are environmental standards in soils such as factory sites and landfills. Heavy metals may be present in concentrations higher than those specified in. Many heavy metals are highly toxic and not only adversely affect the environment but also accumulate in the body and cause harm. In recent years, regulations on heavy metals tend to be stricter, such as the establishment of environmental standards for heavy metals contained in incinerated ash, fly ash, soil, and the like.
As one method for detoxifying substances containing heavy metals, Patent Document 1 (Japanese Patent Application Laid-Open No. 2001-132930) discloses heating in an incinerator ash containing heavy metals at a melting point or lower. However, a method of cooling and separating and recovering after volatilizing heavy metals has been proposed. However, most of the heavy metals contained in the incinerated ash are oxides, and the heavy metals present in the form of oxides are high boiling point compounds, and thus are difficult to remove and remain in the treated product.

As a method for improving this, in Patent Document 2 (Japanese Patent Laid-Open No. 2002-192118), as shown in FIG. 4, a waste containing heavy metals and chlorine stored in a tank 61 is heated in a rotary kiln 60. , A method of chlorinating heavy metals with a chlorine-based gas generated at that time to volatilize the heavy metals is disclosed.
In Patent Document 3 (Japanese Patent Application Laid-Open No. 11-114530), first, a chlorine-based gas is supplied to incineration ash or the like in a heating furnace to chlorinate heavy metals, and then a volatile treatment is performed in a high-temperature furnace. Is disclosed.
In this way, the heavy metal-containing substance is heated in the presence of a chlorine-based gas, and the heavy metal is chlorinated to facilitate volatilization at a low boiling point, and then the temperature is raised, and the chlorinated heavy metal is volatilized and cooled, trapped. Chlorination and volatilization methods for collecting and recovering heavy metals have been proposed as an effective method for separating heavy metals.

  However, in Patent Document 2, the chlorine-based gas generated by the heat treatment is led to the exhaust gas line near the incineration ash inlet to cool the exhaust gas and recover the heavy metals. May not be sufficiently contacted with the metal, resulting in insufficient chlorination of the heavy metal, and heavy metal may remain in the treated product. Further, in Patent Document 3, there is a problem that fuel consumption is large with respect to the temperature rise of the heating furnace, and in the heating furnace, the contact efficiency between the chlorine-based gas and the processed material is poor, and heavy metals remain. Furthermore, in Patent Document 4 (Japanese Patent Application Laid-Open No. 11-179317), as pretreatment, a chlorine-based gas or incinerator exhaust gas from a chlorine-based gas source decomposition is used, and heavy metals such as incineration ash are heated at less than 600 ° C. A method is disclosed in which it is chlorinated and then heat-treated in a high temperature range of about 600 ° C. to 850 ° C. to volatilize and recover heavy metals. However, in this case, there is a problem that the processing time is long and the temperature control is complicated and time-consuming, and there is a problem that it cannot be applied to equipment not equipped with an incinerator.

JP 2001-132930 A JP 2002-192118 A JP 11-114530 A Japanese Patent Laid-Open No. 11-179317

  Accordingly, in view of the above-mentioned problems of the prior art, the present invention can sufficiently carry out chlorination of heavy metals with sufficient contact between the heavy metals and the chlorine-based gas, and maintain high removal efficiency of heavy metals after the treatment. It is possible to minimize the residual of heavy metals, reduce the cost by suppressing the supply of thermal energy, and reduce the load on the treatment facility by the exhaust gas containing chlorine used for chlorination An object of the present invention is to provide a method and apparatus for detoxifying heavy metal-containing substances, and the system.

Therefore, in order to solve such problems, the present invention heats an object to be treated containing heavy metals together with a chlorine-based gas, chlorinates the heavy metals, volatilizes them, and volatilizes and removes them. In the processing method,
After introducing the object to be treated into a fluidizing furnace and chlorinating heavy metals contained in the object to be treated while blowing the chlorine-based gas from the bottom of the fluidizing furnace and flowing the object to be treated,
The object to be treated is introduced into a heating furnace, and the chlorinated heavy metals are volatilized and separated in the heating furnace.

  According to the present invention, since a fluidizing furnace is used in which a workpiece is fluidized by a chlorine-based gas blown from the furnace bottom, the contact efficiency between the chlorine-based gas and the workpiece is improved, and chlorination of heavy metals is achieved. Can be promoted.

In addition, in the detoxification method of the heavy metal-containing material, the object to be treated containing heavy metals is heated together with a chlorine-based gas, and the heavy metals are chlorinated and then separated and removed.
The material to be treated is introduced into a fluidizing furnace, and a chlorine-based gas is blown from the bottom of the fluidizing furnace, and the material to be treated is contained in the material to be treated in the lower space of the fluidizing furnace while flowing the material to be treated. After chlorinating heavy metals
The chlorinated heavy metals are volatilized and separated in an upper space of the fluidizing furnace.

  In the present invention, the temperature settings of the lower space and the upper space of the fluidizing furnace are made different, and each is maintained in a temperature range suitable for chlorination or volatilization treatment of heavy metals. Preferably, the lower space is about 400 to 800 ° C and the upper space is about 800 to 1200 ° C. As a result, chlorination and volatilization can be performed with a single device, and the device can be downsized and the installation cost can be reduced. Also in the present invention, since chlorination is performed in a fluidized state, the contact efficiency between the object to be treated and the chlorine-based gas is improved, and chlorination can be performed efficiently.

Furthermore, the object to be treated containing heavy metals is heated together with a chlorine-based gas, and the heavy metals are chlorinated and then volatilized and separated, and the flue gas containing the separated heavy metals is recombusted. In the detoxification treatment method for heavy metal-containing substances, including an exhaust gas treatment step of cooling after recombustion in and collecting dust of the cooled exhaust gas,
In the heavy metal separation step, the object to be treated is introduced into a fluidizing furnace, and the heavy metal is chlorinated while flowing the object to be treated by blowing chlorine gas from the furnace bottom. Introducing into a heating furnace, volatilizing and separating the chlorinated heavy metals,
It is characterized in that at least a part of the reburned chlorine-based exhaust gas is extracted upstream from the cooling as the chlorine-based gas, and the chlorine-based exhaust gas is introduced into the fluidizing furnace.

According to the present invention, the object to be treated is fluidized by introducing a chlorine-based gas, and the chlorination of heavy metals is mainly performed to improve the contact efficiency between the object to be treated and the chlorine-based gas. It will be done efficiently. In addition, by using the chlorinated exhaust gas after re-combustion or after re-combustion and before gas cooling for the fluidization, it is possible to eliminate or reduce the input of heat energy in chlorination, and the heat energy in volatilization treatment. Input can be reduced. This is because the temperature of the recombustion exhaust gas is about 700 to 900 ° C. Furthermore, by circulating the chlorine-based exhaust gas, it is possible to reduce the load of the desalination treatment of the exhaust gas treatment device installed in the subsequent stage and to suppress the corrosion of the piping and other equipment.
The cooling of the chlorine-based exhaust gas includes cooling of the exhaust gas by heat exchange with a medium such as air, and cooling of the exhaust gas by means such as water spray.

In addition, as an invention of an apparatus that suitably implements these, the object to be treated containing heavy metals is heated together with a chlorine-based gas, and the heavy metals are chlorinated and then volatilized, and then removed and separated to remove harm. In the processing device,
A fluidizing furnace for chlorinating heavy metals contained in the workpiece, and a heating furnace for volatilizing and separating the chlorinated heavy metals,
The fluidizing furnace has a chlorine-based gas introduction means at the furnace bottom, and chlorinates heavy metals while fluidizing the material to be treated by introducing the chlorine-based gas.

Furthermore, in the detoxification processing apparatus of the heavy metal containing substance which heats the to-be-processed substance containing heavy metals with chlorine gas, volatilizes the said heavy metals, and volatilizes and separates and removes them,
It has a chlorinated gas introduction means at the bottom of the furnace, and includes a fluidizing furnace for flowing the object to be processed by introducing the chlorinated gas,
A chlorination zone for chlorinating the heavy metals is formed in the lower space of the fluidizing furnace, and a volatilization treatment zone for volatilizing and separating the heavy metals is formed in the upper space.

In addition, a heavy metal separation device that heats an object to be treated containing heavy metals together with a chlorine-based gas, volatilizes the heavy metals, and volatilizes them to separate and remove,
An exhaust gas treatment facility comprising a recombustion chamber for exhaust gas containing the separated heavy metals, a gas cooling device for cooling the reburned exhaust gas, and a dust collector for collecting the cooled exhaust gas. In the detoxification treatment system for heavy metal-containing substances,
The heavy metal separation device has a chlorine-based gas introduction means at the furnace bottom, and a fluidizing furnace for chlorinating heavy metals while flowing the material to be treated by introducing chlorine-based gas; and the chlorinated heavy metals A heating furnace that volatilizes and separates
The chlorine-based gas is a chlorine-based exhaust gas extracted from the re-combustion chamber or a chlorine-based exhaust gas extracted from the downstream side of the re-combustion chamber and the upstream side of the gas cooling device.
In the invention, for example, when the chlorine-based exhaust gas is insufficient with respect to the heavy metal content of the object to be treated, at least a part of the chlorine-based exhaust gas discharged from the heating furnace together with the chlorine-based exhaust gas. Is preferably introduced into the fluidizing furnace. In addition to the chlorine-based exhaust gas, a chlorine-based gas such as chlorine gas or hydrogen chloride gas supplied from outside the processing system may be used.

As described above, according to the present invention, since chlorination is performed using a fluidizing furnace in which an object to be processed is fluidized by a chlorine-based gas blown from the bottom of the furnace, the contact efficiency between the chlorine-based gas and the object to be processed And the chlorination of heavy metals can be promoted.
Also, by changing the temperature settings of the lower space and upper space of the fluidizing furnace and maintaining each in a temperature range suitable for chlorination or volatilization treatment of heavy metals, chlorination and volatilization treatment can be performed with a single device. This can be done, and the downsizing of the apparatus and the reduction of the installation cost can be achieved.
Further, in the exhaust gas treatment facility, the chlorine-based exhaust gas after re-combustion or after re-combustion and before gas cooling is introduced into the fluidizing furnace to fluidize the material to be treated, so that heat energy can be input in chlorination. It is possible to eliminate or reduce the amount of heat energy used in the volatilization process. Furthermore, by circulating the chlorine-based exhaust gas, it is possible to reduce the load of the desalination treatment of the exhaust gas treatment apparatus installed in the subsequent stage, and to suppress the corrosion of the piping and other equipment.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.
FIG. 1 is a block diagram of a processing apparatus for heavy metal containing materials according to the first embodiment, FIG. 2 is a block diagram of a processing apparatus for heavy metal containing substances according to the second embodiment, and FIG. 3 is a heavy metal according to the third embodiment. It is a whole block diagram of the ash processing system which equipped with the processing apparatus of the kind containing substance.
This example is a technique for separating and removing heavy metals such as Pb, Zn, As, Cd, Cr, Se, Hg, Sb, Cu, etc., and examples of treated materials include contaminated soil, incinerated ash, fly ash, etc. In particular, in the present embodiment, the incineration ash detoxification process will be described as an example.

The heavy metal-containing material detoxifying device shown in FIG. 1 is a device for detoxifying incineration ash 30 discharged from incineration equipment. Incineration ash 30 containing heavy metals is introduced and the incineration ash 30 is chlorinated. A fluidizing furnace 40 for heating in the presence of a system gas to chlorinate heavy metals, and a heating furnace 10 for heating the incinerated ash 30 containing the chlorinated heavy metals to volatilize the heavy metals. Composed.
The fluidizing furnace 40 is provided with a chlorine-based gas inlet at the bottom, heated to a temperature of about 400-800 ° C. in a reducing atmosphere while blowing the chlorine-based gas 32 and flowing the incinerated ash 30, Try to make chloride.
Examples of the chlorine gas 32 include chlorine gases such as chlorine gas, hydrogen chloride gas, and chlorine exhaust gas.

The incinerated ash 30 containing chlorinated heavy metals is introduced into the heating furnace 10 and heated to below the melting point of the incinerated ash in a reducing atmosphere, for example, about 500 ° C. to 1200 ° C. to volatilize and separate the heavy metals. At this time, a rotary kiln, an electric furnace, or the like can be used as the heating furnace 10. Volatilized heavy metals are led to an exhaust gas treatment facility (not shown) in the subsequent stage, cooled to below the melting point of heavy metals, and separated and recovered.
As described above, by using the fluidizing furnace 40 for flowing the incineration ash with the chlorine-based gas 32 blown from the bottom, the contact efficiency between the chlorine-based gas 32 and the object to be treated is improved, and the chlorination of heavy metals is promoted. it can.

As shown in FIG. 2, the detoxification processing apparatus for heavy metal-containing material according to the second embodiment is configured by a fluidizing furnace 40 in which incinerated ash 30 containing heavy metals is introduced and a chlorination process is performed. The fluidizing furnace 40 heats the incinerated ash 30 to about 400 to 800 ° C. in a reducing atmosphere while flowing the incinerated ash 30 with the chlorine gas 32 introduced from the bottom, and converts the heavy metals in the incinerated ash 30 to chloride. A zone 40A is formed in the lower space, and in the upper space, an object to be treated containing chlorinated heavy metals is heated in a reducing atmosphere below the melting point of the incinerated ash 30, for example, in a temperature range of 800 ° C. to 1200 ° C. The volatilization process area 40B which volatilizes heavy metals is formed.
The heavy metals volatilized in the volatilization treatment area 40B are guided to a subsequent exhaust gas treatment facility, cooled to below the melting point of the heavy metals, and separated and recovered.
According to the present embodiment, the contact efficiency between the chlorine-based gas and the incineration ash 30 is improved, and the chlorination of heavy metals can be promoted. Moreover, since chlorination and volatilization are performed in one fluidizing furnace 40, it is possible to reduce the size of the apparatus and reduce the installation cost.

The ash treatment system shown in FIG. 3 is a system for detoxifying incineration ash and fly ash discharged from the incineration facility, and includes a pretreatment device 20 that performs pulverization treatment of the incineration ash 30 and the like, and pretreatment incineration. The ash 30 is appropriately mixed with fine-grained coal and heated in the presence of a chlorine-based gas to volatilize the heavy metals contained in the chlorinated incineration ash 30 and the fluidizing furnace 40 for chlorination of the heavy metals. A rotary kiln 10 to be separated and an exhaust gas treatment facility for treating exhaust gas discharged from the rotary kiln 10 are configured.
The exhaust gas treatment facility combusts exhaust gas containing heavy metals discharged from the fluidizing furnace 40 and the rotary kiln 10 by supplying auxiliary fuel 34, and performs recombustion to decompose and remove dioxins and the like contained in the exhaust gas. Heat exchange between the chamber 21 and the high-temperature exhaust gas discharged from the re-combustion chamber 21 and the combustion air 36, preheating the combustion air 36 and cooling the high-temperature exhaust gas, and the air preheating A gas cooling tower 25 that cools the exhaust gas cooled by the vessel 22 to about 250 ° C. or less by spraying cooling water, a bag filter 26 that collects fly ash 37 in the cooled exhaust gas, and an induction fan from the bag filter And a chimney 28 for exhausting the exhaust gas discharged by the outside 27 to the outside.

  The fluidizing furnace 40 includes a heat-resistant hopper 41 that stores the incinerated ash 30, a conveyor 42 that supplies the pretreated incinerated ash 30 into the furnace, a valve 43 that discharges the incinerated ash 30 chlorinated by a predetermined amount, A pressurizer 45 for pressurizing the chlorine-based exhaust gas, and a chlorine-based exhaust gas outlet 44 having a plurality of ejection nozzles for introducing the pressurized chlorine-based exhaust gas from the bottom of the heat-resistant hopper 41, and 400 to 800 The incinerated ash 30 is brought into contact with the chlorine-based exhaust gas while flowing through the chlorine-based exhaust gas ejected from the chlorine-based exhaust gas outlet 44 in a hopper maintained at ℃, and the heavy metals contained in the incinerated ash are chlorinated. . At this time, some of the low boiling point heavy metals are volatilized and separated, and migrate into the exhaust gas.

  The rotary kiln 10 mixes the incinerated ash which has been chlorinated by the fluidizing furnace 40 with fine coal and appropriately feeds the incinerated ash 30 from the input hopper 11 to the other end side. A cylindrical furnace body 12 having means, an ash discharge port 15 provided on the other end side of the charging hopper 11 of the furnace body 12, and a burner portion provided on the ash discharge port 15 side of the furnace body 12 13. The incinerated ash 30 introduced into the rotary kiln 10 is roasted at a temperature of about 500 to 1200 ° C. by the flame generated by the burner unit 13 by supplying the air 33 and the auxiliary fuel 34 while being transferred to the ash discharge port 15. Is done. At this time, the rotary kiln 10 has a reducing atmosphere in an oxygen-deficient state or an oxygen-free state so that the incinerated ash 30 is not oxidized and burned.

The supply amount of the air 33 and the auxiliary fuel 34 is controlled so that the furnace body 12 has a melting point of the incinerated ash 30 or less, for example, the temperature on the burner unit 13 side is about 1200 ° C.
In the present embodiment, in the rotary kiln 10, heavy metals chlorinated by the fluidizing furnace 40 are volatilized and separated by heating of the burner unit 13, and the volatilized heavy metals are mixed in the gas and are discharged from the exhaust gas outlet. Discharged. At this time, chlorination of heavy metals remaining without being chlorinated proceeds simultaneously due to the action of the chlorinated material contained in the incinerated ash 30.
In the third embodiment, in addition to the illustrated rotary kiln 10, any apparatus that can heat the incinerated ash, such as a fluidized furnace or an electric furnace, can be used.

  The exhausted heavy metals contained in the exhaust gas are introduced into the gas cooling tower 25 through the recombustion chamber 21 and the air preheater 22, and are cooled to the melting point of the heavy metals or less by the gas cooling tower 25. The deposited heavy metals are collected and reused or discarded. The ash detoxified in the furnace body 12 is cooled by the ash cooling device 16 and discharged as roasted ash 35.

  In the third embodiment, the chlorine-based exhaust gas A introduced into the fluidizing furnace 40 is branched from the exhaust gas line immediately after the re-combustion chamber 21 of the exhaust gas treatment facility, or the re-combustion chamber 21. Chlorinated exhaust gas B extracted from The chlorine-based exhaust gas A and the chlorine-based exhaust gas B contain chlorine components because the incineration ash 30 is heated in the rotary kiln 10 and the chlorine content contained in the incineration ash volatilizes and moves into the exhaust gas. Yes. Further, since the recombustion chamber 21 is heated by the supply of the auxiliary fuel 34, the chlorinated exhaust gases A and B discharged therefrom are in a high temperature state of 700 to 900 ° C. Therefore, by introducing the chlorine-based exhaust gas A or B into the fluidizing furnace 40, it is possible to heat the fluidizing furnace 40 with little heat energy without the need for supplying heat energy from the outside. Can be chlorinated.

Further, since the chlorine-based exhaust gas A or B is configured to be pressurized by the pressurizer 45 and ejected from the chlorine-based exhaust gas outlet 44, the incinerated ash 30 accumulated at the bottom of the hopper is violently generated by the high-pressure ejected gas. When fluidized and stirred, the contact efficiency between the chlorine component in the gas and the heavy metals in the incinerated ash becomes very high, and the efficiency of chlorination is improved.
Moreover, in this Example 3, since the incineration ash 30 supplied to the rotary kiln 10 which performs the volatilization process of heavy metals is preheated by the fluidizing furnace 40, the thermal energy supplied to the rotary kiln 10 is reduced. It becomes possible.

At this time, the content of heavy metals in the incinerated ash 30 and the chlorine content in the incinerated ash 30 and / or the chlorine content in the chlorinated exhaust gases A and B are detected. A supply amount of the chlorine-based exhaust gases A and B to the fluidizing furnace 40 may be set. Further, both of the chlorinated exhaust gases A and B may be supplied to the fluidizing furnace 40.
Furthermore, when the chlorine content of the chlorine-based exhaust gas A, B is insufficient with respect to the heavy metal content in the incineration ash 40, the chlorine-based exhaust gas C discharged from the rotary kiln 10 may be supplied, Chlorine gas may be added from the outside. Examples of the chlorine gas 32 include chlorine gases such as chlorine gas and hydrogen chloride gas. In addition, chlorine-based exhaust gas branched from the upstream side of the bag filter 26 may be supplied.

  On the other hand, the exhaust gas generated in the fluidizing furnace 40 is guided to a cyclone 46, and the exhaust gas from which the ash 47 has been separated by the cyclone 46 is returned to the exhaust gas line upstream of the bag filter 26. The exhaust gas return position includes, for example, an exhaust gas line D discharged from the rotary kiln 10, an exhaust gas line E between the recombustion chamber 21 and the air preheater 22, and between the air preheater 22 and the gas cooling tower 25. Exhaust gas line F, an exhaust gas line G between the gas cooling tower 25 and the bag filter 26, and the like. Further, when the separated ash 47 is generated, it is preferable that the separated ash 47 is treated again with the incinerated ash 30.

  As described above, according to the present embodiment, the fluidizing furnace 40 is provided in the front stage of the rotary kiln 10, and the incinerated ash and the chlorine-based exhaust gas are brought into contact with each other in the fluidized state, whereby efficient chlorination can be achieved. Moreover, the chlorine-type exhaust gas A or B discharged | emitted from the recombustion chamber 21 is as high as 700-900 degreeC, and it is possible to make the fluidization furnace 40 into a high temperature state. Accordingly, it is possible to reduce the supply of thermal energy without particularly heating the fluidizing furnace 40. Furthermore, by circulating the chlorine-based exhaust gas, it is possible to reduce the load of the desalination treatment of the exhaust gas treatment device installed in the subsequent stage and to suppress the corrosion of the piping and other equipment.

In addition, the test result by the testing machine to which the present Example 3 is applied is shown below. At this time, the chlorine-based exhaust gas A discharged from the recombustion chamber 21 was used as the chlorine-based exhaust gas supplied to the fluidizing furnace 40. The amount of HCl required when 42.6 kg of dry ash having a Pb content of 778 mg / kg was treated with a test machine and reduced to a Pb content of 252 mg / kg after treatment was as follows. The processing time is 1 hour.
(HCl concentration) x (HCl addition amount) ÷ (HCl molar mass) x (treatment time)
= (1200 x 10 ^-3 [g / l]) x (6.6 x 10-3 [l / h]) ÷ (36.461 [g / mol]) x 1 [h]
= 0.000217 [mol]
Thus, the required HCl amount in the testing machine is 0.000217 [mol].

Further, the amount of HCl required for the processing apparatus assuming an actual machine is obtained by proportional calculation from the test result obtained by the test machine.
(Test machine throughput): (Required HCl volume of test machine) = (Assumed throughput of actual machine): (Required HCl volume of actual machine)
0.0426 [kg]: 0.000217 [mol] = 7750 [kg]: X
Therefore, the actual amount of HCl assumed is 39.48 [mol]. The assumed processing capacity of the processing apparatus is 7.75 t / h (186 t / d), and the processing time is 1 hour.
In addition, the HCl concentration of the chlorinated exhaust gas discharged from the recombustion chamber per hour from the assumed actual machine is as follows.
(Dry gas amount) x (HCl concentration) ÷ (HCl molar mass) x (time)
= (13200 [m ³ _N / h]) x (1500 x 10 ^-3 [g / m ³ _N ]) ÷ (36.461 [g / mol]) x (1 [h])
Thus, the HCl concentration of the chlorinated exhaust gas is 543.054 [mol].

Therefore, when the chlorinated exhaust gas discharged from the recombustion chamber is applied in the assumed fluidizing furnace and the method of chlorination is carried out, the ratio of the chlorinated exhaust gas required for chlorination is as follows: .
(Actual required HCl amount for actual machine) ÷ (Actual exhausted HCl level for actual machine) x 100
= 39.48 [mol] ÷ 543.05 [mol] x 100
= 7.3%
Dry gas volume: 13200 [m ³ _N / h] × 0.073 = 963.6 [m ³ _N / h]
Thus, according to the present embodiment, a system that can be sufficiently realized even when an actual machine is assumed can be provided.

It is a block diagram of the processing apparatus of the heavy metal containing substance which concerns on this Example 1. FIG. It is a block diagram of the processing apparatus of the heavy metal containing substance which concerns on the present Example 2. FIG. It is a whole block diagram of the ash processing system which comprised the processing apparatus of the heavy metal containing substance which concerns on this Example 3. FIG. It is a block diagram which shows the processing apparatus of the conventional heavy metal containing substance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rotary kiln 12 Furnace main body 13 Burner part 16 Ash cooling device 20 Pretreatment device 21 Recombustion chamber 22 Air preheater 25 Gas cooling tower 26 Bag filter 30 Incineration ash 32 Chlorine gas 35 Roasting ash 40 Fluidization furnace 40A Chlorination zone 40B Volatilization treatment area 41 Heat-resistant hopper 42 Conveyor 43 Valve 44 Chlorine exhaust gas outlet 45 Pressurizer 46 Cyclone

Claims (7)

In the method for detoxifying heavy metal-containing substances, the object to be treated containing heavy metals is heated together with a chlorine-based gas, and the heavy metals are chlorinated and then separated and removed.
After introducing the object to be treated into a fluidizing furnace and chlorinating heavy metals contained in the object to be treated while blowing the chlorine-based gas from the bottom of the fluidizing furnace and flowing the object to be treated,
A method for detoxifying a heavy metal-containing material, wherein the object to be treated is introduced into a heating furnace, and the chlorinated heavy metals are volatilized and separated in the heating furnace. In the method for detoxifying heavy metal-containing substances, the object to be treated containing heavy metals is heated together with a chlorine-based gas, and the heavy metals are chlorinated and then separated and removed.
The material to be treated is introduced into a fluidizing furnace, and a chlorine-based gas is blown from the bottom of the fluidizing furnace, and the material to be treated is contained in the material to be treated in the lower space of the fluidizing furnace while flowing the material to be treated. After chlorinating heavy metals
A method for detoxifying a heavy metal-containing substance, characterized by volatilizing and separating the chlorinated heavy metal in an upper space of the fluidizing furnace. A treatment object containing heavy metals is heated together with a chlorine-based gas, and the heavy metals are chlorinated and then volatilized and separated, and the exhaust gas containing the separated heavy metals is re-combusted in a recombustion chamber. An exhaust gas treatment step of cooling after reburning and collecting the cooled exhaust gas, and a detoxification treatment method for a heavy metal-containing substance,
In the heavy metal separation step, the object to be treated is introduced into a fluidizing furnace, and the heavy metal is chlorinated while flowing the object to be treated by blowing chlorine gas from the furnace bottom. Introducing into a heating furnace, volatilizing and separating the chlorinated heavy metals,
A heavy metal containing substance characterized in that at least a part of the reburned chlorine-based exhaust gas upstream of the cooling is extracted as the chlorine-based gas, and the chlorine-based exhaust gas is introduced into the fluidizing furnace. Detoxification treatment method. In a detoxification processing apparatus for heavy metal-containing substances that heats an object to be processed containing heavy metals together with a chlorine-based gas, chlorinates the heavy metals, volatilizes them, and separates and removes them.
A fluidizing furnace for chlorinating heavy metals contained in the workpiece, and a heating furnace for volatilizing and separating the chlorinated heavy metals,
The fluidizing furnace has a chlorine-based gas introducing means at the bottom of the furnace, and chlorinates heavy metals while flowing the material to be processed by introducing the chlorine-based gas. apparatus. In a detoxification processing apparatus for heavy metal-containing substances that heats an object to be processed containing heavy metals together with a chlorine-based gas, chlorinates the heavy metals, volatilizes them, and separates and removes them.
It has a chlorinated gas introduction means at the bottom of the furnace, and includes a fluidizing furnace for flowing the object to be processed by introducing the chlorinated gas,
A heavy metal containing material characterized in that a chlorination zone for chlorinating the heavy metals is formed in the lower space of the fluidizing furnace, and a volatilization treatment zone for volatilizing and separating the heavy metals is formed in the upper space. Detoxification processing equipment. A heavy metal separation device that heats an object to be treated containing heavy metals together with a chlorine-based gas, chlorinates the heavy metals, volatilizes them, and separates and removes them;
An exhaust gas treatment facility comprising a recombustion chamber for exhaust gas containing the separated heavy metals, a gas cooling device for cooling the reburned exhaust gas, and a dust collector for collecting the cooled exhaust gas. In the detoxification treatment system for heavy metal-containing substances,
The heavy metal separation device has a chlorine-based gas introduction means at the furnace bottom, and a fluidizing furnace for chlorinating heavy metals while flowing the material to be treated by introducing chlorine-based gas; and the chlorinated heavy metals A heating furnace that volatilizes and separates
The heavy metal-containing substance, wherein the chlorine-based gas is a chlorine-based exhaust gas extracted from the re-combustion chamber or a chlorine-based exhaust gas extracted from the downstream side of the re-combustion chamber and the upstream side of the gas cooling device Detoxification treatment system. The heavy metal-containing material detoxification system according to claim 6, wherein at least a part of the chlorine-based exhaust gas discharged from the heating furnace is introduced into the fluidizing furnace together with the chlorine-based exhaust gas.

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