JP3405873B2 - Halogenated hydrocarbon-containing waste treatment apparatus and treatment method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for decomposing organic halides generated when treating general wastes and industrial wastes, and particularly to a gas containing a high concentration of organic halides. The present invention relates to a decomposition treatment method and a decomposition treatment device.

[0002]

2. Description of the Related Art Conventionally, when disposing of household electric appliances, they have been treated as general waste when discarded by general consumers, and as industrial waste when discarded by businesses. As described above, even when treating the same waste home electric appliances, the treatment differs depending on the disposal source, but the concrete treatment method is mainly landfill treatment in both cases.

Among the above-mentioned waste home electric appliances, for example, a waste refrigerator uses a foamed polyurethane resin as a heat insulating material, and the foaming agent for this foamed polyurethane resin is, for example, CFC-11 or CFC-12. Halogenated hydrocarbons have been mainly used.

[0004] When such a waste home electric appliance containing a halogenated hydrocarbon as a constituent material, such as a waste home electric appliance containing a foamed polyurethane resin as a constituent material, is subjected to a landfill treatment, CFC-11 is chronologically changed. And CFC
There is a risk that halogenated hydrocarbons such as -12 will be released.

Since the discovery of the ozone hole, the depletion of the ozone layer by specific CFCs has become a problem due to the heightened environmental awareness on a global scale. CFC-11 and CFC-1
Specified CFCs such as 2 diffuse into the stratosphere as they are without being decomposed because they are relatively stable substances when released into the atmosphere.

As a result, CFC-11, CFC-12 and the like in the stratosphere are decomposed by strong ultraviolet rays from the universe, causing destruction of the ozone layer. It has been found that when the ozone layer is destroyed, a large amount of harmful ultraviolet rays reach the ground, causing various adverse effects such as destruction of biological systems and harm to the human body.

From the above, CFC-11 and CF
The use and treatment of halogenated hydrocarbons such as C-12 as specified CFCs are internationally regulated, and for the treatment of waste home appliances that may release CFCs into the atmosphere, simply use landfill. Instead, it is required to disassemble and detoxify specific CFCs in advance and then dispose of them. On the other hand, it is also considered to use alternative CFCs such as HCFC-22 and HFC-134a in place of specific CFCs such as CFC-11 and CFC-12. However, these alternative CFCs also have non-zero ozone depletion potential. However, it is not necessarily harmless, and it is required to gradually reduce the use.
Therefore, dispose of the CFC substitutes and detoxify them as well as other wastes that have the risk of discharging halogenated hydrocarbons, including wastes made of expanded polyurethane resin containing these CFC substitutes as foaming agents. Is required.

Foamed polyurethane resins containing halogenated hydrocarbons such as the above specified CFCs or alternative CFCs as a foaming agent are classified into soft foams and hard foams depending on the raw materials and the degree of cross-linking. Hard foams are widely used as automobile parts, packaging containers, etc., and as heat insulating materials, sound absorbing materials, etc.

As described above, the foamed polyurethane resin containing a halogenated hydrocarbon as a foaming agent is used not only in waste refrigerators but also in various fields. Therefore, a waste material containing such foamed polyurethane resin as a constituent material is used. There is a demand for a treatment method capable of efficiently detoxifying a halogenated hydrocarbon in advance and then treating the same. In particular, in the refrigerator, in addition to the specific freon for foaming, the particular freon is also used for the refrigerant, so it is important to recover and detoxify these at the same time, but such a point is unsolved. There is.

By the way, as a method for decomposing / detoxifying these halogenated hydrocarbons, a combustion method, a plasma decomposition method, an ultraviolet decomposition method, a catalytic method, etc. are known, and various research institutions including universities and companies are known. We are conducting research on the practical application and improvement of methods for decomposing and detoxifying these halogenated hydrocarbons.

Among them, the catalytic method is considered to be the most practical method because it consumes a small amount of energy for decomposition, has a high decomposition rate, and can downsize the device.

However, the catalyst is apt to react with halogen or a halogen compound produced by the decomposition of halogenated hydrocarbon to form a fluoride or a chloride, and particularly 0.5% by volume.
This tendency becomes remarkable when the above-mentioned gas containing a high concentration halogenated hydrocarbon is treated. Therefore, there is a problem that the catalytic activity becomes unstable, the catalytic function is deteriorated, and the catalyst life is shortened.

In the conventional apparatus and method for decomposing halogenated hydrocarbons by the catalytic method, a low concentration of 0.5% by volume or less of halogenated hydrocarbons is passed through a tube filled with a catalyst for decomposing. . In the decomposition treatment of halogenated hydrocarbons by the conventional catalytic method, the decomposition rate begins to decrease when the concentration of halogenated hydrocarbons exceeds 0.5%, and decomposition occurs when the concentration of halogenated hydrocarbons is 2% by volume. There was a problem that the rate decreased to about 70% (see FIG. 5).

Further, even if treated at such a low concentration,
There is a problem that the catalyst activity is unstable, the catalyst life is short, and the catalyst must be replaced regularly.
This has led to a complicated processing apparatus and an increase in processing cost.

[0015]

As described above, the CF
Specified CFCs such as C-11 and CFC-12 cause environmental problems. Therefore, the specified CFCs should be treated beforehand with the foamed polyurethane resin containing it as a foaming agent and other halogenated hydrocarbon-containing wastes containing halogenated hydrocarbons. There is a strong demand for a method of decomposing / detoxifying and then treating. Also,
The same applies to waste containing alternative CFCs.

As described above, there is a strong demand for an effective and efficient method and apparatus for treating wastes containing a foamed polyurethane resin containing a harmful halogenated hydrocarbon as a foaming agent.

The present invention has been made to solve such a problem, and efficiently treats halogenated hydrocarbon-containing wastes such as foamed resins containing specific CFCs or alternative CFCs as a foaming agent. It is an object of the present invention to provide a halogenated hydrocarbon-containing waste treatment device and treatment method capable of performing the treatment. It is another object of the present invention to provide a halogenated hydrocarbon-containing waste treatment device and treatment method capable of decomposing a relatively high concentration of halogenated hydrocarbons while maintaining a high decomposition rate for a long time.

[0018]

DISCLOSURE OF THE INVENTION A halogenated hydrocarbon-containing waste treatment device of the present invention is used to foam halogenated hydrocarbons.
Emission of halogenated hydrocarbon-containing gas from foamed resin used as an agent
A halogenated hydrocarbon discharge means for issued before discharged
Halogenated hydrocarbon in gas containing halogenated hydrocarbon
Halogenated hydrocarbon concentration measuring means for measuring the concentration
Depending on the measured value of
And a halogenated hydrocarbon concentration adjusting means for adjusting the concentration of the halogenated hydrocarbon in the halogenated hydrocarbon-containing gas to 0.5 to 5% by volume , and the halogenated hydrocarbon-containing gas in which the concentration is adjusted. The halogenated hydrocarbon of ZrO
_And a halogenated hydrocarbon decomposing means for decomposing with a catalyst in which 0.5 to 50% by weight of Cr ₂ O ₃ is carried on _two carriers.

[0019]

The halogenated hydrocarbon discharging means includes not only discharging the halogenated hydrocarbon-containing gas from the foamed resin or the like, but also introducing the recovered halogenated hydrocarbon itself into the processing system. This also applies to the cases that are not particularly described below.

The halogenated hydrocarbon concentration can be controlled by
A halogenated hydrocarbon concentration measuring means for measuring the discharged halogenated hydrocarbon concentration of halogenated hydrocarbon-containing gas, a dilution gas in the halogenated hydrocarbon containing gas in accordance with the halogenated hydrocarbon concentration measured it can be more achieved the dilution gas introducing means for introducing.

The halogenated hydrocarbon decomposing means is Zr.
The halogenated hydrocarbon in the halogenated hydrocarbon-containing gas may be decomposed by a catalyst in which 0.5 to 50% by weight of Cr ₂ O ₃ is carried on an O ₂ carrier.

Further, immediately after the halogenated hydrocarbon discharge means, a hydrocarbon recovery means for separating and recovering the hydrocarbon gas generated from the halogenated hydrocarbon-containing waste from the halogenated hydrocarbon-containing gas may be provided. Good.

The hydrocarbon recovery means may be configured to condense and recover the hydrocarbon gas, and for example, an oiling device or the like may be used.

The halogenated hydrocarbon-containing waste treatment method of the present invention comprises a halogenated hydrocarbon discharging step of discharging a halogenated hydrocarbon-containing gas from a foamed resin using halogenated hydrocarbon as a foaming agent , The said halogenated carbonization discharged
A method for measuring the concentration of halogenated hydrocarbons in hydrogen-containing gas
Depending on the process of measuring the concentration of the hydrogenated hydrocarbon and the measured value
By introducing a diluent gas into the halogenated hydrocarbon-containing gas, the concentration of the halogenated hydrocarbon in the halogenated hydrocarbon-containing gas can be adjusted.
A halogenated hydrocarbon concentration adjusting step of adjusting the 0.5-5% by volume, 0.5 to halogenated hydrocarbon of the halogenated hydrocarbon-containing gas was adjusted to a concentration of ZrO ₂ carrier
And a halogenated hydrocarbon decomposing step of decomposing using a catalyst supporting 50% by weight of Cr ₂ O ₃ .

[0026]

In the halogenated hydrocarbon concentration adjusting step, the halogenated hydrocarbon concentration in the halogenated hydrocarbon containing gas discharged from the halogenated hydrocarbon containing waste is adjusted to 0.5 to 5% by volume. You may

Further, in the halogenated hydrocarbon concentration adjusting step, the halogenated hydrocarbon concentration in the halogenated hydrocarbon containing gas discharged from the halogenated hydrocarbon containing waste is adjusted to 0.5 to 3% by volume. You may

In the decomposition treatment of a halogenated hydrocarbon by the conventional catalytic method, the concentration of the halogenated hydrocarbon is 0.
When it exceeds 5% by volume, the decomposition rate decreases, but in the halogenated hydrocarbon-containing waste treatment method of the present invention, the decomposition rate does not decrease even when the concentration of halogenated hydrocarbon exceeds 0.5%.

Further, in the decomposition treatment of halogenated hydrocarbons by the conventional catalytic method, when an attempt was made to treat halogenated hydrocarbons having a concentration of about 2% by volume, the decomposition rate decreased to about 70%. Even when treating a halogenated hydrocarbon with a concentration of about 10% by volume, a decomposition rate of about 75% can be maintained.

Further, in the decomposition treatment of halogenated hydrocarbons by the conventional catalytic method, when the treatment of halogenated hydrocarbons with a concentration of about 0.5% by volume is performed, the decomposition rate is about 96.
However, in the present invention, a decomposition rate of about 96% can be maintained even when a halogenated hydrocarbon having a concentration of about 5% by volume is treated.

Further, according to the present invention, when the halogenated hydrocarbon is treated at a higher concentration of 0.5 to 3% by volume than the conventional one, the decomposition of the halogenated hydrocarbon is as high as 99%. Processing can be performed.

Further, the halogenated hydrocarbon discharging step may use a dry distillation method or a combustion method.

Immediately after the halogenated hydrocarbon discharging step, a hydrocarbon recovery step for recovering the hydrocarbon gas generated from the halogenated hydrocarbon-containing waste by separating the halogenated hydrocarbon from the contained gas is provided. May be.

In this hydrocarbon recovery step, the hydrocarbon gas may be condensed and recovered, for example, an oiling device or the like may be used.

Further, the halogenated hydrocarbon concentration adjusting step is
The step of measuring the halogenated hydrocarbon concentration in the discharged halogenated hydrocarbon-containing gas, and introducing a diluent gas into the halogenated hydrocarbon-containing gas in accordance with the measured value to measure the halogen content in the halogenated hydrocarbon-containing gas. And a step of adjusting the concentration of the converted hydrocarbon.

In the halogenated hydrocarbon concentration adjusting step , the concentration may be adjusted by discharging the halogenated hydrocarbon gas from the foamed resin which is the halogenated hydrocarbon-containing waste of which the size is adjusted.

Further, the halogenated hydrocarbon decomposition step is performed by Zr.
The halogenated hydrocarbon gas in the halogenated hydrocarbon-containing gas may be decomposed by a catalyst in which 0.5 to 50% by weight of Cr ₂ O ₃ is carried on an O ₂ carrier.

[0039] That is, halogenated hydrocarbon containing waste processing apparatus and method of the present invention is an apparatus decomposed by catalytic method the discharged halogenated hydrocarbons halogenated hydrocarbon containing waste, the discharge means The halogenated hydrocarbon-containing gas discharged from the halogenated hydrocarbon-containing material is introduced into a halogenated hydrocarbon decomposition means and decomposed by a catalyst.

The target substance to be treated in the present invention is a halogenated hydrocarbon-containing waste using a halogenated hydrocarbon as at least a part of the constituent material. For example, a foamed resin using a halogenated hydrocarbon as a foaming agent,
In particular, it is a heat insulating material using a polyurethane resin. And
As a method of discharging halogenated hydrocarbons such as regulated CFCs from these waste drugs, there are a dry distillation method of steaming in an oxygen-free state and a combustion method of incinerating the waste itself.

Further, in the present invention, a halogenated hydrocarbon gas itself such as a recovered halogenated hydrocarbon is also targeted as the treatment substance. In this case, air, nitrogen, by adjusting the recovered halogenated hydrocarbon concentration introduced from reservoir (exhaust) is diluted with rare gas or the like, discharge of foamed resin
Like the decomposition treatment of the issued halogenated hydrocarbons, halogenated hydrocarbons containing gas can be stably supplied to the separation means.

In the case of decomposing halogenated hydrocarbons which do not have hydrogen as a constituent element, it is necessary to add a hydrogen source.

For example, when the halogenated hydrocarbon gas is discharged from a foamed resin in which the halogenated hydrocarbon gas is used as the foaming agent, the halogenated hydrocarbon-containing gas
As the discharging means, a carbonization device may be used, or a combustion device may be used. A halogenated hydrocarbon-containing foamed resin crushed to a predetermined size is introduced into such an apparatus, and the foamed resin is heated within a predetermined temperature range, whereby the halogenated hydrocarbon is discharged . The halogenated hydrocarbon discharging means includes temperature control means, nitrogen gas,
A carrier gas introducing unit such as a rare gas may be provided.

Here, an example of the dry distillation method will be described by taking a urethane foam resin as an example.

The urethane resin is melted at about 323 K and halogenated hydrocarbons are discharged. The heat treatment temperature is, for example, about 323 to 573K (preferably 3
73 to 473 K), most of the halogenated hydrocarbon as a foaming agent can be discharged.

Also, after discharging the halogenated hydrocarbon, 453
About ～873K (preferably 493～723K) decomposed urethane resin when held at temperatures of, isocyanates mixed in CO and NO _x, phenol, and the like C1~C8 of hydrocarbon gas is discharged. Of these, those that can be recovered may be recovered by the hydrocarbon recovery means in the latter stage.

The urethane resin decomposes almost completely at 773 to 873K. Even if the temperature at which the urethane resin is decomposed exceeds 873K, not only the above effect cannot be obtained, but also harmful gas such as dioxin may be generated.

Further, for example, the halogenated hydrocarbon may be directly introduced into the system from a refrigerant used in a refrigerator, an air conditioner or the like.

The hydrogen source adding means is for adding a hydrogen source as a decomposition aid to the discharged halogenated hydrocarbon-containing gas. In this case, for example, steam or hydrocarbon may be used as the hydrogen source. HCl by decomposition of halogenated hydrocarbons by adding a hydrogen source
Although (hydrochloric acid) and HF (hydrofluoric acid) are produced, these substances are preferable also in that post-treatment is easy.

When decomposing a halogenated hydrocarbon having no hydrogen as a constituent element, it is necessary to add a hydrogen source.

The amount of hydrogen added is preferably more than the stoichiometric amount sufficient to react with halogenated hydrocarbons to generate HCl and HF.

The halogenated hydrocarbon concentration adjusting means keeps the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas introduced into the halogenated hydrocarbon decomposing means within an appropriate range. In particular, the present invention is an extremely highly efficient treatment apparatus for halogenated hydrocarbon-containing substances that decomposes halogenated hydrocarbons at a high concentration of 0.5 to 10% by volume, and the halogenated hydrocarbons to be introduced into the halogenated hydrocarbon decomposing means. The hydrogen concentration is kept within this range. When a hydrogen source is added to the discharged halogenated hydrocarbon-containing gas, the halogenated hydrocarbon concentration after the addition may be kept within the range of 0.5 to 10% by volume.

As the halogenated hydrocarbon concentration control means,
A halogenated hydrocarbon concentration measuring means for measuring the discharged halogenated hydrocarbon concentration of halogenated hydrocarbon-containing gas, introducing a diluent gas into the halogenated hydrocarbon-containing gas in accordance with the halogenated hydrocarbon concentration measured It may be provided with a diluting gas introducing means for performing the above. As the diluent gas, a chemically inert gas such as nitrogen gas or a rare gas may be used.

Further, depending on the halogenated hydrocarbon concentration measured by a gas concentration meter or the like, the discharge temperature in the halogenated hydrocarbon discharging means or the flow rate of the carrier gas, for example, the content of halogenated hydrocarbon such as foamed resin is included. The halogenated hydrocarbon concentration may be adjusted by changing the input amount of waste. The higher the temperature and the lower the flow rate of the carrier gas, the higher the halogenated hydrocarbon concentration.

Further, when the halogenated hydrocarbon gas is discharged by dry-distilling or burning the foamed resin or the like, it is general that the foamed resin is crushed to an appropriate size and then put into a heating furnace for dry distillation. The halogenated hydrocarbon concentration may be adjusted depending on the size of the resin to be crushed.

The specific size of the foamed resin to be crushed is
Although it depends on the type of waste and the amount that can be treated in the carbonization mechanism, it is preferable to crush it to have a typical diameter of 10 mm or more. This is because when the size of the waste is less than 10 mm, the amount of halogenated hydrocarbons vaporized before the heat treatment increases.

In any case, the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas introduced into the halogenated hydrocarbon-decomposing means in the halogenated hydrocarbon-containing waste treatment device of the present invention is 0.5 to 0.5. It is adjusted to 10% by volume.

Further, the concentration of halogenated hydrocarbons discharged from the waste may be adjusted by the size of the halogenated hydrocarbon-containing foamed resin.

By adjusting the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas to 0.5 to 10% by volume in this manner, it is possible to prevent a large amount of halogenated hydrocarbon from being supplied to the catalyst at one time. Therefore, the decomposition efficiency of the catalyst can be stably maintained.

The halogenated hydrocarbon decomposing means in the apparatus for treating a halogenated hydrocarbon-containing waste of the present invention is used as a catalyst for decomposing a halogenated hydrocarbon-containing gas containing 0.5 to 10% by volume of a halogenated hydrocarbon gas. , ZrO ₂
A catalyst in which Cr ₂ O ₃ is supported on a carrier is used.

The shape of the ZrO ₂ carrier is not particularly limited, and may be any shape that fulfills the function as a carrier, such as pellets formed by firing powder and then extrusion molding, and monoliths such as honeycombs.

The amount of Cr ₂ O ₃ carried on the ZrO ₂ carrier is preferably at least 0.5 to 50% by weight or more. This is because if the amount of Cr ₂ O ₃ supported is less than 0.5% by weight, the catalytic activity will be low.

When the content is 50% by weight or more, Zr which serves as a carrier
The proportion of O ₂ decreases, and the skeleton destruction of the catalyst easily occurs. If skeleton destruction occurs, the function as a catalyst will be lost, so be careful. However, in the case of using a sintering agent that can increase the strength without deteriorating the catalytic ability of Cr ₂ O ₃ for decomposing halogenated hydrocarbons, the supported amount of Cr ₂ O ₃ should be 50% by weight or more. You may

Then, such a catalyst can be used as a means for decomposing a halogenated hydrocarbon by shaping it into a granular form and filling the flow type reaction tube.

The catalyst used is not limited to granular ones, but may be, for example, Cr.
_The composite catalyst in which ZrO ₂ is supported on ₂ O ₃ may be sprayed onto a frame formed so as to have a large surface area, and this frame may be arranged in a flow reaction tube.

Further, this halogenated hydrocarbon decomposing means has a temperature adjusting means such as an electric heating means as in the usual catalytic halogenated hydrocarbon decomposing apparatus, so that the temperature of the reaction part can be adjusted. There is. Therefore, the optimum temperature can be set according to the state of the catalyst, the halogenated hydrocarbon concentration, and the like.

The halogenated hydrocarbon gas decomposed by the halogenated hydrocarbon decomposing means produces free halogen such as fluorine and chlorine. These halogens are converted into halogen compounds such as HCl (hydrochloric acid) and HF (hydrofluoric acid) by hydrogen that constitutes halogenated hydrocarbons or hydrogen added as a decomposition aid, and they are trapped with an alkali to be recovered. You may

The halogen generated by the decomposition may be recovered as calcium chloride or calcium fluoride by using an alkaline earth metal such as calcium as an adsorbent.

Further, hydrocarbons can be recovered as CO ₂ when steam is added as an auxiliary agent. In the decomposition treatment apparatus according to the present invention, the gas temperature of each means is measured by using a gas thermometer or the like. In addition, by constantly monitoring the gas flow rate using a flow rate system, it is possible to control the supply amount of waste, heating temperature, carrier gas, hydrogen source, introduction amount of diluent gas, etc. to halogenate halogenated hydrocarbon-containing gas. The hydrocarbon concentration can be kept constant, and the efficiency of decomposition of the halogenated hydrocarbon by the catalyst can be optimally maintained.

[0070]

DETAILED DESCRIPTION OF THE INVENTION

(Example 1) An example of a halogenated hydrocarbon-containing waste treatment device of the present invention will be described with reference to the drawings.

This processor is CFC-11, CFC-1.
This is an apparatus for treating a foamed resin such as polyurethane containing a regulated CFC such as No. 2 as a foaming agent.

The halogenated hydrocarbon-containing waste treatment device 100 illustrated in FIG. 1 discharges the halogenated hydrocarbon-containing gas from the halogenated hydrocarbon-containing waste.
1, a decomposition treatment unit 102 for decomposing the discharged halogenated hydrocarbons, and a scrubber unit 103 for detoxifying the decomposition products.

The discharging section 101 includes a waste input section 105 for automatically charging a set amount of a waste material 104 containing a halogenated hydrocarbon such as polyurethane into a thermal dry distillation chamber, and a thermal dry distillation method for dry distillation of the waste 104. It is composed of a chamber 106.

The waste 104 containing halogenated hydrocarbons such as polyurethane, which is put into the waste throwing section 105, is previously 2
It may be crushed to a size of 0 to 50 mm square.

The thermal dry distillation chamber 106 is equipped with a heater 107 and a temperature sensor 108 so that the heating temperature of the waste can be controlled.

Further, the halogenated hydrocarbon-containing waste 10
The carrier gas introducing unit 109 for controlling the flow rate of the carrier gas for guiding the gas discharged from the No. 4 to the decomposition processing unit 102 and introducing the carrier gas into the thermal dry distillation chamber 106 is provided. 109
b is a carrier gas reservoir. Carrier gas is N ₂
Was used.

A hydrogen source introducing section 110, a dilution gas introducing section 111, a gas concentration measuring section 112 and a gas flow rate measuring section 113 are arranged between the discharge section 101 and the decomposition processing section 102. 110b is a hydrogen source reservoir, and 111b is a diluent gas reservoir.

The hydrogen source and the diluent gas are introduced into the system by controlling their flow rates. In this device, the gas concentration measuring unit 11
2 uses a gas chromatograph.

Further, in this halogenated hydrocarbon-containing waste treatment device 100, the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas introduced into the decomposition treatment section 102 is in the concentration range of 0.5 to 10% by volume. In order to maintain an appropriate concentration in the inside, the halogenated hydrocarbon-containing waste is disposed according to the halogenated hydrocarbon concentration measured by the gas concentration measuring unit 112 and the flow rate of the halogenated hydrocarbon-containing gas measured by the gas flow rate measuring unit 113. In order to control the feeding speed of the material into the thermal dry distillation chamber 106, the temperature of the thermal dry distillation chamber 106, and the introduction amount of each gas in the carrier gas introduction unit 109, the hydrogen source introduction unit 110, and the dilution gas introduction unit 111 to optimum values. The controller 114 is provided.

The temperature of the decomposition processing section 102 is also adjusted by the control section 114. With these, the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas introduced into the decomposition treatment section 102, the flow rate of the halogenated hydrocarbon-containing gas, and the temperature in the reaction tube are optimized.

The decomposition treatment section 102 is 10 wt% of Cr ₂ O ₃ on a ZrO ₂ carrier which is formed into a granular shape having a diameter of 2 to 3 mm.
A flow-type reaction tube 116 is filled with the supported catalyst 115. The flow reaction tube 116 is a temperature sensor 117.
And a heater 118, so that the temperature inside the reaction tube can be controlled.

FIG. 2 is an enlarged view of this disassembly processing unit.

The scrubber section 103 is provided with a trap 119 for a halide gas such as hydrochloric acid and hydrofluoric acid generated by decomposition of halogenated hydrocarbons, and an afterburner 120 for burning the gas that could not be recovered.

For the trap 119, an alkaline earth metal such as calcium may be used as an adsorbent.

As a result, a gas containing halogenated hydrocarbons at an appropriate concentration within the concentration range of 0.5 to 10% by volume is always supplied to the decomposition treatment section 102, so that stable decomposition treatment is carried out and the catalyst is processed. It became easier to set the replacement time calculated from the service life of the.

FIG. 3 shows an example of a means for separating a hydrocarbon gas generated from a foamed resin from a halogenated hydrocarbon and recovering the hydrocarbon-based gas generated in the latter stage of the discharge part, which is equipped with an oiling device 150 and is used in the halogenation of the present invention. Another one of hydrocarbon-containing waste treatment equipment
It is a figure which shows an example schematically. In addition to this, other means such as using an adsorbent may be taken.

The halogenated hydrocarbon-containing waste treatment device 151 illustrated in FIG. 3 is an oil for recovering recoverable components from gases such as phenol and C1 to C8 hydrocarbon gas produced by thermal decomposition of resin. Equipped with a chemical conversion device.
By disposing such an oiling device, it is possible to suppress the production of by-products in the decomposition processing unit 102 and reduce the load on the scrubber unit 103.

Here, an example of a method for treating the halogenated hydrocarbon-containing waste will be described by taking a foamed polyurethane resin containing CFC-11 as a foaming agent.

A waste throwing unit 105 made of polyurethane crushed to a typical size of about 10 to 50 mm square
Then, it is put into the heat dry distillation chamber 106.

[0090] The thermal carbonization chamber 105 and a carrier gas such as the carrier gas introduction unit 109 for example, N ₂ is introduced, the polyurethane is heated in a non-oxidizing atmosphere. Polyurethane starts melting at about 323K, and CFC-
11 is discharged. This heat treatment temperature is, for example, 323-
Most of CFC-11 can be discharged by maintaining the temperature at about 573K (preferably 373 to 473K).

Also, after discharging CFC-11, 453-87
About 3K (preferably 493～723K) decomposed urethane resin when held at temperatures of, a mix of CO and NO _x isocyanates, phenol, C1 to C8 hydrocarbon gas or the like comes discharged. This may be carried out by recovering, fixing, burning, etc., in the oiling device and the scrubber portion in the subsequent stage.

The polyurethane resin decomposes almost completely at 773 to 873K. Even if the temperature at which the polyurethane is decomposed exceeds 873K, sufficient effects cannot be obtained, and in addition, harmful gas may be generated. Therefore, sufficient caution is required.

The CFC-11 discharged from the polyurethane in the discharging section 101 is guided to the decomposition processing section 102. At this time, the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas is adjusted so as to be maintained at an appropriate concentration within the concentration range of 0.5 to 10% by volume.

For example, the control unit 114 controls the halogenated hydrocarbon-containing waste according to the halogenated hydrocarbon concentration measured by the gas concentration measuring unit 112 and the flow rate of the halogenated hydrocarbon-containing gas measured by the gas flow rate measuring unit 113. It is recommended that the feeding rate of the gas into the hot dry distillation chamber 106, the temperature of the hot dry distillation chamber 106, and the introduction amount of each gas in the carrier gas introduction unit 109, the hydrogen source introduction unit 110, and the dilution gas introduction unit 111 be adjusted to optimum values. Good.

The temperature of the decomposition processing section 102 may also be adjusted by the control section 114.

In the decomposition treatment means, Cr ₂ was added to the ZrO ₂ carrier.
A predetermined concentration of CFC-11 is decomposed by the catalyst supporting O ₃ .

When decomposing, free fluorine and chlorine are produced, but the steam added as a hydrogen source for the decomposition aid causes
Recovered as hydrofluoric acid and hydrochloric acid in the scrubber trap. In addition, carbon that constitutes CFC-11 is discharged or recovered as CO ₂ . Exhaust gas that could not be collected is burned by an afterburner to render it harmless.

FIG. 4 is a diagram schematically showing an example of a halogenated hydrocarbon-containing waste treatment device for treating recovered halogenated hydrocarbons.

The recovered halogenated hydrocarbon is introduced to the decomposition treatment section 102 together with a carrier gas such as N ₂ . The concentration adjustment, hydrogen source addition and the like can be performed in the same manner as described above. Reference numeral 160 is a recovered halogenated hydrocarbon reservoir.

Example 2 A ZrO ₂ carrier carrying 10% by weight of Cr ₂ O ₃ was shaped into a particle having a diameter of 2 to 3 mm to form a catalyst, which was filled in a flow-type reaction tube whose temperature could be controlled.

A halogenated hydrocarbon gas was introduced into this reaction tube, and the change in the decomposition rate of the halogenated hydrocarbon when the concentration of the halogenated hydrocarbon was changed was analyzed by gas chromatography with the gas before and after the decomposition. Examined.

The halogenated hydrocarbon is CFC-11.
And the pure air containing this is changed to a space velocity of 4800 hr ^-1.
Was flown into a flow-type reaction tube at a temperature of 500 ° C.

As a comparative example, a composite oxide carrier composed of SiO ₂ and TiO ₂ was loaded with 1.0 wt% of Pt.
ZrO ₂ that is formed into a granular material having a diameter of up to 3 mm to form a catalyst
Carry 2.0% by weight of H ₃ PO ₄ on the carrier and 2-3 mm
FIG. 5 shows the results of evaluation in the same manner as described above for the catalyst formed by molding into a granular shape.

In all of the catalysts of the comparative examples, the decomposition rate of halogenated hydrocarbons was remarkably reduced when the concentration of halogenated hydrocarbons was 1% by volume or more. You can see that it is stable.

In the decomposition treatment of halogenated hydrocarbons by the conventional catalytic method shown as a comparative example, the decomposition rate decreases when the concentration of halogenated hydrocarbons exceeds 0.5% by volume. In the halogenated hydrocarbon-containing waste treatment method, the decomposition rate does not decrease even if the concentration of halogenated hydrocarbon exceeds 0.5%.

Further, in the conventional treatment, when an attempt is made to treat a halogenated hydrocarbon having a concentration of about 2% by volume, the decomposition rate is reduced to about 70%, but in the present invention, the concentration is about 1%.
Even when treating 0% by volume of halogenated hydrocarbon, a decomposition rate of about 75% is maintained.

Further, according to the present invention, even when the halogenated hydrocarbon is treated at a concentration higher than the conventional level of 0.5 to 3% by volume, the decomposition of the halogenated hydrocarbon is as high as 99%. Processing can be performed.

As described above, in the halogenated hydrocarbon decomposition treatment according to the present invention, first, in a high concentration region of 0.5% by volume or more of halogenated hydrocarbon, which has not been conventionally performed because the decomposition rate is lowered. Can be decomposed. Further, the decomposition rate of the halogenohydrocarbon decomposition treatment of a relatively high concentration by the conventional method can be performed at a high concentration of 10% by volume.

Next, FIG. 6 shows the results of examining the change over time (lifetime) in the decomposition rate of halogenated hydrocarbons using these catalysts.

Pure air containing 5% by volume of CFC-11 as a reaction gas was flowed at a space velocity of 4800 hr ^-1 into a flow-through type reaction tube filled with a catalyst, and the temperature of the reaction tube was set to 200 ° C.
And All of the catalysts used as comparative examples lose their catalytic activity within a few hours after the start of the test, resulting in a reduction in the decomposition rate of halogenated hydrocarbons. It can be seen that the decomposition rate of halogenated hydrocarbons can be stably maintained.

Example 3 Using ZrO ₂ as a carrier and Cr ₂
A catalyst having different amounts of supported O ₃ was formed into a granule having a diameter of 2 to 3 mm and having 12 kinds of necks to obtain a catalyst.

Next, these catalysts were filled in a flow-type reaction tube, and changes in the halogenated hydrocarbon decomposition rate were examined. In addition,
As a reaction gas, a gas containing 1% by volume of CFC-11 generated by dry distillation of a polyurethane heat insulating material was used as a space velocity 480.
Flow the reaction tube at 0 hr ^-1 for 5 hours at the temperature of the reaction tube.
It was set to 00 ° C. In addition, the gas before and after the decomposition was analyzed by a gas chromatograph to determine the decomposition rate of halogenated hydrocarbons.

FIG. 7 shows the test result at this time.

The amount of Cr ₂ O ₃ supported is 0.5 to 50% by weight.
In the case of, it is understood that the halogenated hydrocarbon decomposition rate is high.

Example 4 A ZrO ₂ carrier carrying 10% by weight of Cr ₂ O ₃ was formed into a particle having a diameter of 2 to 3 mm to form a catalyst, which was filled in a flow-type reaction tube. Then, changes in the decomposition rate of halogenated hydrocarbons with and without the addition of a hydrogen source to the reaction gas were investigated.

2% by volume of water vapor as a hydrogen source was added to pure air containing 1% by volume of CFC-11 as a reaction gas.
A comparative test was conducted with and without addition, and the space velocity of the reaction gas was set to 4800 hr ^-1 .

Further, the gas before and after the decomposition was analyzed by a gas chromatograph to obtain the decomposition rate of halogenated hydrocarbons. Figure 8
Indicates the test results at that time.

To decompose 99% or more of halogenated hydrocarbons, a temperature of 600 ° C. or higher is required without adding a hydrogen source, while 400 ° C. is sufficient with the addition of steam. .

As described above, by adding the hydrogen source, the treatment at a lower temperature becomes possible, and the generation of harmful gas such as dioxin can be prevented or suppressed.

Example 5 FIG. 9 shows that a polyurethane heat insulating material was selected as a foamed resin containing a halogenated hydrocarbon (CFC-11), and the change in the amount of halogenated hydrocarbon discharged depending on the size of the polyurethane heat insulating material was examined. It is a figure which shows the result.

As described above, since the amount of CFC-11 discharged changes depending on the size of the polyurethane heat insulating material, it is possible to control the amount of halogenated hydrocarbon discharged by adjusting these appropriately. As is clear from FIG.
Crushing to a typical size below 10 mm square will increase the amount of halogenated hydrocarbon gas dissipated from the polyurethane insulation due to the crushing. Therefore,
When crushing foamed resin such as waste polyurethane insulation, it is preferable that the typical size be larger than 10 mm square.

Even when the halogenated hydrocarbon gas itself is discharged and decomposed as in the case of the recovered halogenated hydrocarbon, the halogenated hydrocarbon concentration should be adjusted by diluting it with a carrier gas or a diluent gas. Is possible.

[0123]

As described above, according to the apparatus and method for decomposing a halogenated hydrocarbon-containing waste of the present invention, a gas containing 0.5 to 10% by volume of a halogenated hydrocarbon is added to ZrO ₂ gas. By decomposing using a catalyst supporting Cr ₂ O ₃ on a carrier, the decomposition of halogenated hydrocarbons, which was conventionally performed at low concentration, can be efficiently performed at high concentration.
Moreover, the catalytic ability can be maintained for a long time. Therefore, it is possible to reduce the cost for catalyst replacement and the like, and to reduce the halogenated hydrocarbon treatment cost.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an example of the configuration of a halogenated hydrocarbon-containing waste treatment device of the present invention.

FIG. 2 is an enlarged view showing a halogenated hydrocarbon decomposition treatment section.

FIG. 3 is a diagram schematically showing another example of the configuration of the halogenated hydrocarbon-containing waste treatment device of the present invention.

FIG. 4 is a diagram schematically showing another example of the configuration of the halogenated hydrocarbon-containing waste treatment device of the present invention.

FIG. 5 is a graph showing the halogenated hydrocarbon concentration dependency of the halogenated hydrocarbon decomposition rate according to Examples and Comparative Examples of the present invention.

FIG. 6 is a graph showing changes over time in the decomposition rate of halogenated hydrocarbons according to Examples and Comparative Examples of the present invention.

FIG. 7: Cr ₂ O _{3 when} the loading amount of Cr ₂ O ₃ is changed
/ Shows the halogenated hydrocarbon decomposition rate ZrO ₂ based catalyst.

FIG. 8 is a diagram showing the hydrogen source addition dependency of the halogenated hydrocarbon decomposition rate according to the present invention.

FIG. 9 is a graph showing changes in the amount of halogenated hydrocarbons discharged according to the size of the polyurethane heat insulating material.

[Explanation of symbols]

101 ... Ejection unit, 102 ... Disassembly processing unit, 103 ...
Scrubber 104 ... Waste containing halogenated hydrocarbons, 105 ...
Waste input part 106 ... Thermal distillation chamber, 107 ... Heater, 108 ...
Temperature sensor 109 ... Carrier gas inlet, 109b ... Carrier gas reservoir 110 ... Hydrogen source inlet, 110b ... Hydrogen source reservoir 111 ... Diluting gas inlet, 111b ... Diluting gas reservoir 112 ... Gas concentration measuring unit , 113 ... Gas flow rate measuring section 114 ... Control section, 115 ... Catalyst, 116 ... Flow type reaction tube 117 ... Temperature measuring section, 118 ... Heater, 119 ...
… Trap 120 …… Afterburner, 150 …… Oilizer 160 …… Recovered halogenated hydrocarbon reservoir

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI // C08J 11/00 CEU B09B 5/00 Q (72) Inventor Mina Sasaki 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Prefecture Toshiba Corporation Living space system technology research institute (72) Inventor Tadao Machida 8 Shinsita-cho, Isogo-ku, Yokohama-shi, Kanagawa In-house, Toshiba Living Space System Technology Research (56) Reference JP-A-3-106419 (JP, A) JP-A-5-147039 (JP, A) JP-A-6-226242 (JP, A) JP-A-4-313344 (JP, A) JP-A-8-238418 (JP, A) JP-A-8-10572 (JP , A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) A62D 3/00 B01D 53/86 ZAB B01J 23/26 B09B 5/00 C07B 61/00 300

Claims (4)

(57) [Claims] 1. Foaming using a halogenated hydrocarbon as a foaming agent
Halogenated hydrocarbon discharging means for discharging the halogenated hydrocarbon containing gas from the resin, and halogen in the discharged halogenated hydrocarbon containing gas.
Measurement of halogenated hydrocarbon concentration
A fixed means and diluted to a halogenated hydrocarbon-containing gas according to this measurement value
Introducing a gas to adjust the concentration of halogenated hydrocarbons in the halogenated hydrocarbon-containing gas to 0.5 to 5% by volume , and in the halogenated hydrocarbon-containing gas whose concentration is regulated 0.5 to 50% by weight of halogenated hydrocarbon on ZrO ₂ carrier
And a halogenated hydrocarbon decomposing means for decomposing with a catalyst carrying Cr ₂ O ₃ as described above. 2. Foaming using a halogenated hydrocarbon as a foaming agent
A halogenated hydrocarbon discharging step for discharging a halogenated hydrocarbon containing gas from the resin, and a halogenation in the discharged halogenated hydrocarbon containing gas.
Measurement of halogenated hydrocarbon concentration
A constant step, diluted to a halogenated hydrocarbon-containing gas in response to the measured value
Introducing a gas to adjust the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas to 0.5 to 5% by volume , and in the halogenated hydrocarbon-containing gas whose concentration is adjusted 0.5 to 50% by weight of halogenated hydrocarbon on ZrO ₂ carrier
And a halogenated hydrocarbon decomposing step of decomposing using a catalyst carrying Cr ₂ O ₃ as described above. 3. The halogenated hydrocarbon concentration adjusting step adjusts the halogenated hydrocarbon concentration in the halogenated hydrocarbon-containing gas extracted from the halogenated hydrocarbon-containing waste to 0.5 to 3% by volume. Claims characterized in that
2. The method for treating waste containing halogenated hydrocarbon according to 2 . 4. further comprising a hydrocarbon recovery step of separating and recovering hydrocarbon gas generated from the halogenated hydrocarbon containing waste immediately after the halogenated hydrocarbon ejection process from the halogenated hydrocarbon containing gas Characterized contract
The method for treating a halogenated hydrocarbon-containing waste according to any one of claim 2 or 3 .