JP2001300498A - Method and apparatus for treating refuse by carbon dioxide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus for treating refuse with carbon dioxide while suppressing the generation of dioxins. SOLUTION: A refuse treatment chamber 1 and a gas heating tank 10 are provied and the gas heating tank 10 is equipped with an electric heater 11 for heating a heat accumulation material 13 and a heat transfer pipe 12 heated by the heat accumulation material 13 and a gas supply part 2 of carbon dioxide G is connected to the inlet of the heat transfer pipe 12 and the refuse treatment chamber 1 is connected to the outlet of the heat transfer pipe 12. The gas supply part 2 is equipped with a gas cylinder 3 filled with carbon dioxide G and carbon dioxide G is sent to the heat transfer pipe 12 from the gas cylinder 3 and the gas heating tank 10 heats carbon dioxide G sent to the heat transfer pipe 12 to form high temperature carbon dioxide (high temperature gas g1) and refuse D is heat-treated by the high temperature gas g1, which is sent from the gas heating trank 1, in the refuse treatment chamber 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for treating refuse with carbon dioxide gas of waste containing combustibles.

[0002]

2. Description of the Related Art At present, garbage discharged from households, garbage discharged from factories and offices, and garbage such as driftwood drifting on river banks and shores are increasing year by year with the improvement of daily life. Processing is a major social issue. Of these wastes, as a means of treating combustible waste, a method is adopted in which most are incinerated and incinerated ash is abandoned in landfills. When incinerating combustible waste, harmful dioxin (two benzenes) is used. Organic compound having a structure in which the ring is bridged by two molecules of oxygen).
It is incinerated at the above high temperature.

[0003]

When combustible waste is incinerated, dioxin (more specifically, highly toxic 2,3,7,8-tetrachlorinated dioxin) is generated at 200 to 750 ° C. There was a problem that combustion had to be performed at a high temperature of not less than ° C. This is because dioxin is generated when the combustion temperature is 800 ° C. or less when chlorine-based substances (such as salt) in combustible waste as organic substances are burned under certain conditions. A high-temperature incinerator at 800 ° C. or higher has a problem that the scale becomes large and expensive, and dioxin is generated in the middle of reaching 800 ° C. from the start of use of the incinerator. Then, this invention was made in view of such a problem which a prior art has, and aims at the refuse disposal method by the carbon dioxide gas which suppressed generation | occurrence | production of dioxin, and the refuse disposal method. An object of the present invention is to provide a suitable refuse treatment apparatus.

[Means for Solving the Problems]

In order to achieve the above object, according to a first aspect of the present invention, there is provided a refuse treatment method in which refuse in a refuse treatment chamber is heated with a high-temperature carbon dioxide gas (high-temperature gas). According to a second aspect of the present invention, in the waste disposal method of the first aspect, a mixed gas comprising carbon dioxide gas after heating the dust (gas after heating) and volatile components generated from the dust is condensed by a heat exchanger,
A carbon dioxide gas (recovered gas) is recovered from the mixed gas, and the recovered gas is heated and reused as a high-temperature gas. Claim 3
In the refuse treatment method of claim 2, at least one of a refrigerant that condenses the mixed gas and a liquefied volatile component condensed by the heat exchanger is used for preheating the refuse. According to a fourth aspect of the present invention, in the refuse disposal method of the first, second or third aspect,
The garbage is carbonized by being heated by a high-temperature gas at 300 to 600 ° C in an oxygen-free state.

Here, garbage refers to flammable garbage that is mainly incinerated among garbage discharged from homes, garbage discharged from factories and offices, and garbage that has drifted to riversides and coasts. . Here, the temperature of the carbon dioxide gas (high-temperature gas) for heating the garbage is 300 to 600 ° C., and the anoxic state means that the carbon dioxide gas is continuously sent to the garbage processing chamber after the garbage processing chamber is sealed, This is achieved by discharging the mixed gas from the processing chamber, and by heating the garbage in an oxygen-free state, it is decomposed without burning and carbonized, that is,
It refers to the treatment that suppresses the production of dioxin. Here, the heat exchanger means that a mixed gas composed of carbon dioxide gas (heated gas) whose temperature has been reduced due to the heating of dust and volatile components generated from the dust is condensed by a refrigerant, and the carbon dioxide gas (recovered gas) is collected from the mixed gas. Gas),
The refrigerant refers to water and the like.

According to a fifth aspect of the present invention, there is provided a refuse treatment apparatus including a refuse treatment chamber and a gas heating tank, wherein the gas heating tank includes an electric heater, a heat transfer tube, and a heat storage material. A gas supply unit for carbon dioxide gas is connected to the inlet side of the heat transfer tube, and a refuse treatment chamber is connected to the outlet side of the heat transfer tube. According to a sixth aspect of the present invention, in the refuse treatment apparatus according to the fifth aspect, a mixed gas comprising carbon dioxide gas (gas after heating) after refuse heating and volatile components generated from refuse is provided between the refuse treatment chamber and the gas supply unit. And the gas recovery unit is provided with a heat exchanger. According to a seventh aspect of the present invention, in the refuse treatment apparatus according to the sixth aspect, the heat exchanger connects an intake path of the mixed gas to the refuse treatment chamber, and the carbon dioxide gas recovered from the mixed gas to the gas supply unit. An air supply path for the recovered gas is connected, and a cooling pipe for a refrigerant that condenses the mixed gas and an outflow pipe for condensed and liquefied volatile components are provided. According to an eighth aspect of the present invention, at least one of the outflow pipe and the cooling pipe is connected to a waste processing chamber to preheat the waste.

Here, the gas heating tank is a tank in which a heat storage material is heated by an electric heater, a heat transfer tube is heated by the heat storage material, and carbon dioxide gas supplied to the heat transfer tube is heated to 300 to 600 ° C. Here, the gas supply unit refers to a unit that supplies carbon dioxide gas to the gas heating tank, and the gas recovery unit reuses carbon dioxide gas after refuse treatment, and is generated from refrigerant and refuse in the heat exchanger. A substance that enables effective use with volatile components.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a refuse treatment method and a refuse treatment apparatus according to the present invention will be described with reference to FIG. 1. A refuse treatment chamber 1 and a gas heating tank 10 are provided. A heat storage material 13 heated by the heater 11 and a heat transfer tube 12 heated by the heat storage material 13 are provided. The gas supply unit 2 for the carbon dioxide gas G is connected to the inlet side of the heat transfer tube 12, and the heat transfer tube 12 is connected to the outlet side of the heat transfer tube 12. The refuse treatment chamber 1 is connected, the gas supply unit 2 includes a gas cylinder 3 filled with carbon dioxide gas G, sends the carbon dioxide gas G from the gas cylinder 3 to the heat transfer tube 12, and the gas heating tank 10 The temperature of the carbon dioxide gas G sent to 12 is raised to a high-temperature carbon dioxide gas (high-temperature gas g1), and the refuse treatment chamber 1 heats the trash D with the high-temperature gas g1 sent from the gas heating tank 10. .

The gas supply unit 2 fills the gas cylinder 3 with the carbon dioxide gas G, and has an opening / closing valve 4 between the gas cylinder 3 and the heat transfer tube 12. Supply. Gas heating tank 10
Converts the carbon dioxide gas G supplied to the heat transfer tube 12 to 300
The temperature is raised to about 600 ° C., and is sent to the refuse treatment chamber 1 as a high-temperature gas g1 of 300 ° C. or more. The refuse treatment chamber 1 is sealed after the refuse D is charged, and the refuse D is heated by the high-temperature gas g1 in an oxygen-free state to be carbonized to form a carbide E like charcoal having a large amount of open pores. Is what makes it possible.

Since the first embodiment has the same structure as described above, the on-off valve 4 of the gas cylinder 3 is opened during dust disposal,
When the carbon dioxide gas G is supplied from the gas supply unit 2 to the heat transfer tube 12 of the gas heating tank 10, the carbon dioxide gas G supplied to the heat transfer tube 12 is heated by the heat storage material 13 and the high-temperature gas g 1
Becomes The refuse D introduced into the refuse treatment chamber 1 is thermally decomposed in an atmosphere of the high-temperature gas g1 in an oxygen-free state, so that it can be treated without generating dioxin. In addition, since near-infrared rays and far-infrared rays are generated from the high-temperature gas g1 or the like, the dust D can be heated in a short time. By changing the supply amount of the carbon dioxide gas G to the gas heating tank 10, the high-temperature gas g
Since the air supply amount can be adjusted, it is suitable for the refuse treatment chamber 1 which requires a large heating at the start of use.

The second embodiment of the refuse treatment method and the refuse treatment apparatus according to the present invention will be described only with respect to parts different from the first embodiment. The gas recovery unit 5 is provided with a heat exchanger 6 and an air supply fan 7, and the temperature of the heat exchanger 6 is lowered between the waste processing chamber 1 and the waste processing chamber 1 by heating the waste D. A carbon dioxide gas (hereinafter referred to as a heated gas g2);
An intake path 61 for mixed gas H composed of volatile components h generated from dust D is connected, and mixed gas H
An air supply path 62 for the carbon dioxide gas (hereinafter referred to as a recovered gas g3) is connected to the cooling pipe 64 of the refrigerant W for condensing the mixed gas H, and a condensed liquefied substance F of the volatile component h.
Outflow pipe 63 and the air supply fan 7 is connected to the air supply path 62.

In the second embodiment, the gas recovery unit 5 is provided between the waste processing chamber 1 and the gas supply unit 2 as in the above structure.
To the mixed gas H composed of the heated gas g2 after the dust treatment and the volatile component h generated from the dust D,
The mixed gas H is condensed by the refrigerant W, and the component h in the mixed gas H is liquefied to form a liquefied product F, and the heated gas g2
To form a recovered gas g3. If the recovered gas g3 is returned to the gas supply unit 2 and supplied again to the gas heating tank 10, the carbon dioxide gas G can be recycled and used effectively.

By recovering the mixed gas H in the refuse treatment chamber 1 by the gas recovery unit 5, it is possible to suppress an increase in the pressure in the refuse treatment chamber 1, that is, to reduce the pressure resistance of the refuse treatment chamber 1. Therefore, the waste disposal chamber 1 can be provided at low cost. Further, the liquefied substance F of the volatile component h generated from the dust D
However, if, for example, wood vinegar liquefied product F generated from wood garbage and bamboo vinegar liquefied product F generated from bamboo trash, these liquefied products F are used as a therapeutic solution for athlete's foot, an insect repellent solution, a soil conditioner and the like. obtain.

The third embodiment of the refuse treatment method and the refuse treatment apparatus according to the present invention will be described only with respect to parts different from the second embodiment. The outflow of the liquefied material F provided in the heat exchanger 6 as shown in FIG. At least one of the pipe 63 and the cooling pipe 64 for the coolant W is guided to the refuse treatment chamber 1, and particularly, the cooling pipe 64 is provided so as to circulate between the refuse treatment chamber 1 and the heat of the liquefied material F or the coolant W The garbage D is preheated using energy.

Since the third embodiment has the same structure as described above, the liquefied material F liquefied in the heat exchanger 6 is led to the refuse treatment chamber 1 or the refrigerant W is circulated between the refuse treatment chamber 1 and the refrigerant. Since the thermal energy of W and the liquefied material F is used for preheating the dust D, the supply amount of the carbon dioxide gas G used for heating the dust D can be reduced. That is, energy saving is promoted.

[0016]

[Experimental example] Specifications of gas heating tank 10 Capacity of electric heater 11 = 27 KW, heat storage amount = 270 KW
h Effective heat storage temperature = 150 to 500 ° C Maximum heat output = 100 KW, temperature drop when standing = 0.4%
/ Heat storage material 13 = Magnesia 2700Kg, nitrate 370k
g Heat transfer tube 12 is a steel tube, outer diameter = 22.2 mm, wall pressure =
1 mm, length = 40 M, heat transfer area = 2.8 m ² .

10 kg of waste material is put into the refuse treatment chamber 1, the refuse treatment chamber 1 is sealed, and 300 to 50
When the high-temperature gas g1 at 0 ° C. is sent for 10 minutes to 1 hour, decomposition starts when the organic matter of the waste material is heated to 200 ° C. or higher, and almost decomposes and carbonizes at 300 ° C. or higher,
In about 20 minutes, 1 kg of carbide E was obtained, but no dioxin was generated during that time. That is, the treatment could be performed without generating dioxin. This carbide E is
Since it is in the form of charcoal, it can be used as it is as a water purifying material or a hygroscopic material for buildings, or it can be crushed and used as a substitute for activated carbon.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the refuse treatment chamber 1, if there is no measure for handling the mixed gas H, the pressure in the refuse treatment chamber 1 increases, and the pressure resistance of the entire system must be increased.
It becomes an expensive device. The heating of the carbon dioxide gas G is not limited to heating by the gas heating tank 10, and heating by other means is also possible. The refrigerant W and the liquefied material F of the heat exchanger 6 can be used for purposes other than the preheating of the refuse D, for example, a steam-water mixer. The heat storage material 13 is filled with a mixture of magnesia and sodium nitrate / sodium nitrite / potassium nitrate, and the heat resistant temperature of the mixture is 600 ° C.

[0019]

The dust processing method according to the present invention is as described above, and has the following effects. In the refuse treatment method according to the first aspect, since the refuse is heated with a high-temperature carbon dioxide gas and treated in a charcoal-burning state without burning with the high-temperature gas, no dioxin is generated. According to the refuse treatment method of claim 2, in addition to the effect of claim 1, the recovered gas is recovered from the heated gas and can be used again as high-temperature carbon dioxide gas, so that the consumption of carbon dioxide gas is reduced, Garbage disposal costs are reduced.

According to a third aspect of the present invention, in addition to the effects of the second aspect, in addition to the effect of the second aspect, the thermal energy of a liquefied substance obtained by condensing volatile components generated by heating the refuse and a condensing refrigerant is effective for preheating the refuse. Since it is used, it is possible to provide a waste disposal room with low energy consumption. The garbage disposal method of claim 4 is
In addition to the effects of the first, second, and third aspects, since dirt is heated and carbonized in an oxygen-free state, no dioxin is generated.

Since the refuse treatment apparatus according to the present invention has the above structure, the following effects can be obtained. Claim 5
The garbage disposal system heats carbon dioxide gas in a gas heating tank and heats the garbage in the garbage disposal room with the high-temperature gas.
Carbonizes without burning and does not generate dioxin. The refuse treatment apparatus according to claim 6 has a gas recovery unit with a heat exchanger in addition to the effect of claim 5,
A mixed gas composed of a gas after heating in a heat exchanger and a volatile component generated by heating the refuse is condensed, and the recovered gas can be reused from the condensed gas.

According to the seventh aspect of the present invention, in addition to the effect of the sixth aspect, the refrigerant of the heat exchanger and the condensed and liquefied volatile component can be used. According to the refuse treatment apparatus of claim 8, in addition to the effect of claim 7, since the refuse is preheated by the refrigerant and the liquefied material, a refuse treatment chamber with low energy consumption can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a first embodiment of a dust processing method according to the present invention and a dust processing apparatus used in the dust processing method.

FIG. 2 is a schematic view showing a second embodiment of a dust processing method according to the present invention and a dust processing apparatus used in the dust processing method.

FIG. 3 is a schematic view showing a third embodiment of a dust processing method according to the present invention and a dust processing apparatus used in the dust processing method.

FIG. 4 is a process diagram of (a), (b), (c), and (d) dust processing.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Garbage disposal room 2 Gas supply part 3 Gas cylinder 4 On-off valve 5 Gas recovery part 6 Heat exchanger 7 Air supply fan 10 Gas heating tank 11 Electric heater, 12 Heat transfer tube, 13 Heat storage material, 14
Heat insulation material 61 Intake path, 62 Air supply path, 63 Outflow pipe, 64 Cooling pipe G Carbon dioxide gas g1 High temperature gas, g2 Heated gas, g3 Collected gas H Mixed gas, h Volatile component D garbage, E carbide W Refrigerant F Volatilization Liquefied component

Claims (8)

[Claims] 1. A refuse treatment method using carbon dioxide gas, comprising heating refuse (D) in a refuse treatment chamber (1) with high-temperature carbon dioxide gas (high-temperature gas g1). 2. A heat exchanger (6) condenses a mixed gas (H) composed of carbon dioxide gas after heating of dust (gas g2 after heating) and a volatile component (h) generated from dust (D). 2. The refuse treatment according to claim 1, wherein a carbon dioxide gas (recovered gas g3) is recovered from the mixed gas (H), and the recovered gas (g3) is heated and reused as a high-temperature gas (g1). Method. 3. A refrigerant (W) for condensing a mixed gas (H).
The refuse treatment method according to claim 2, wherein at least one of the liquefied product (F) of the volatile component (h) condensed in the heat exchanger (6) is used for preheating the refuse (D). . 4. The garbage (D) is 300 to 60 in anoxic condition.
The method according to claim 1, 2, or 3, wherein the carbonization is performed by heating with a high-temperature gas (g1) at 0 ° C. 5. A refuse treatment chamber (1) and a gas heating tank (10).
The gas heating tank (10) includes an electric heater (11), a heat transfer tube (12), and a heat storage material (13).
A refuse treatment characterized in that a gas supply unit (2) for carbon dioxide gas (G) is connected to the inlet side of (2), and a refuse treatment chamber (1) is connected to the outlet side of the heat transfer tube (12). apparatus. 6. A carbon dioxide gas (dusted gas g after heating) between the waste treatment chamber (1) and the gas supply unit (2).
2) and a recovery unit (5) for a mixed gas (H) composed of a volatile component (h) generated from the refuse (D), and the gas recovery unit (5) includes a heat exchanger (6). The refuse disposal apparatus according to claim 5, wherein: 7. A heat exchanger (6) connects an intake passage (61) for a mixed gas (H) between the heat exchanger (6) and the waste processing chamber (1), and a mixed gas (H) between the heat exchanger (6) and a gas supply unit (2). H) connecting an air supply path (62) for the carbon dioxide gas (recovered gas g3) recovered from the cooling pipe (64) for the refrigerant (W) for condensing the mixed gas (H), and a volatile component (h) 7. A refuse treatment apparatus according to claim 6, further comprising an outflow pipe (63) for condensed and liquefied matter (F). 8. The refuse disposal according to claim 7, wherein at least one of the outflow pipe (63) and the cooling pipe (64) is connected to the refuse treatment chamber (1) to preheat the refuse (D). apparatus.