JP2000239010A - Method and apparatus for producing activated carbon from waste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively obtain an activated carbon useful for removing dioxin of a waste treatment process. SOLUTION: A waste 1 is carbonized by a carbonization furnace 3 to form a carbonization gas 1a and char 1b. The char 1b is fed to an activating furnace 7. The carbonization gas la is burnt by a combustion furnace 11. A generated high-temperature exhaust gas 16 is introduced through a high-temperature exhaust gas line 17 into the activating furnace 7 and is used as a heat source of the activating furnace. A part of the high-temperature exhaust gas 16 is sent to a waste heat recovery boiler 18, steam 19 generated by waste heat recovery is fed to the activating furnace 17 and the char 1b is activated with steam to produce activated carbon 21.

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 producing activated carbon from waste such as municipal waste.

[0002]

2. Description of the Related Art As a current waste disposal system, a combustion system in which waste is burned in an incinerator has been adopted. In recent years, however, there has been a problem of generation of dioxin contained in flue gas. It has been pointed out and has become a social problem.

Therefore, as a next-generation waste treatment method, waste is heated and pyrolyzed in an inert atmosphere, and the generated pyrolysis gas and pyrolysis residue are burned at a high temperature in a melting furnace.
A pyrolysis gasification and melting system has been developed to extract ash from waste as molten slag, and demonstration operation has been performed in some of them.

In the above-mentioned pyrolysis gasification / melting method, the generation of dioxin can be suppressed by burning the pyrolysis residue in a melting furnace at a high temperature of, for example, 1300 ° C. or more. When passing through the exhaust gas treatment device, the temperature decreases, and dioxin is resynthesized.

[0005] Therefore, a gas cooling chamber is placed downstream of the waste heat recovery boiler to rapidly lower the temperature of the molten exhaust gas, and the molten exhaust gas cooled in the gas cooling chamber is used as an exhaust gas treatment device with slaked lime added thereto. It tries to pass a bag filter.

[0006] In recent waste treatment processes, various measures have been taken to remove dioxin. One of them is to inject activated carbon into a bag filter and adsorb dioxin on the activated carbon to remove dioxin. There is a processing method.

[0007]

However, activated carbon,
Generally, it is manufactured by activating palm shells and coal, etc.
The activation method includes chemical activation and gas activation, both of which are often used.However, when the produced activated carbon is blown into a bag filter to remove the dioxin and used, the cost is extremely large. The burden is the actual situation.

Accordingly, an object of the present invention is to provide a method and an apparatus for producing activated carbon from waste so that activated carbon used for dioxin removal in a waste treatment process can be produced at low cost.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is to carbonize waste and supply the char of the produced carbonized gas and char to an activation furnace. To generate high-temperature exhaust gas, a part of the high-temperature exhaust gas is used as a heat source of the activation furnace, and further, steam is generated by recovering waste heat from the remaining portion of the high-temperature exhaust gas. A method and an apparatus for producing activated carbon from waste, which activates char in the activation furnace with steam and the high-temperature exhaust gas to produce activated carbon.

[0010] Since char produced by carbonizing waste is activated by high-temperature exhaust gas obtained by burning carbonized gas and steam generated by waste heat of the high-temperature exhaust gas, activated carbon can be produced at low cost. Can be.

In addition, instead of recovering waste heat from high-temperature exhaust gas to generate steam, water is directly blown into high-temperature exhaust gas supplied as a heat source to an activation furnace to generate steam. It can also be applied to activation furnaces of different heating systems.

Further, by using a part of the high-temperature exhaust gas as a heat source for carbonization of waste, energy can be effectively used.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of an apparatus for producing activated carbon from waste according to the present invention, in which the waste 1 is indirectly thermally decomposed by hot air supplied through a hot air supply line 8 to dry-distill it. Furnace 3 is provided. Also, of the carbonization gas 1a generated from the waste 1 in the carbonization furnace 3 and the char 1b as a carbonization residue, a char extraction line 4 for taking out the char 1b, and a separator 5 for separating and removing non-combustibles 1c from the char 1b. And a pulverizer 6 for pulverizing the char 1b after removing the incombustible material 1c by the separator 5 and removing the char so that the char 1b pulverized by the pulverizer 6 is supplied to the activation furnace 7. The line 4 is connected to the activation furnace 7.

On the other hand, a dust collector 10 such as a cyclone, a combustion furnace 11 and a secondary combustion chamber 2 are installed in a dry distillation gas take-out line 9 for taking out the dry distillation gas 1a from the dry distillation furnace 3. The line 12 is connected to the char take-out line 4 at a position downstream of the crusher 6, and the dust collector 1 is connected.
The dust 1d in the dry distillation gas 1a collected at 0 is supplied to the activation furnace 7 together with the char 1c.
After the dust 1d is collected at 0, the carbonized gas 1a is burned in the combustion furnace 11, and the unburned carbon monoxide contained in the high-temperature exhaust gas 16 is burned in the secondary combustion chamber 2. A high-temperature exhaust gas recovery line 15 branched from the middle of the high-temperature exhaust gas line 13 on the exit side of the combustion furnace 11 is connected to the hot-air supply line 8 so that high-temperature exhaust gas 16 generated in the combustion furnace 11 is used as a heat source of the carbonization furnace 3. And a portion of the high-temperature exhaust gas 16 generated in the combustion furnace 11 is introduced into the activation furnace 7 between the activation furnace 7 and a position in the middle of the high-temperature exhaust gas line 13 of the combustion furnace 11. High-temperature exhaust gas introduction line 17 to be connected.

Further, a waste heat recovery boiler 18 and a gas cooling tower 14 are installed in the high temperature exhaust gas line 13 to recover the high temperature exhaust gas 16 after being led to the high temperature exhaust gas recovery line 15 and the high temperature exhaust gas introduction line 17. The high-temperature exhaust gas 16 after the heat recovery is cooled through the gas cooling tower 14, and the steam 19 is generated by the waste heat recovery boiler 18. Supply line 2 so as to supply
0 is connected to the activation furnace 7 and the char 1 supplied to the activation furnace 7
The activated carbon 21 is manufactured by activating the b and the dust 1 d with the high-temperature exhaust gas 16 and the steam 19. 2
Reference numeral 2 denotes an excess steam line of the waste heat recovery boiler 18 for utilizing excess steam for power generation.

In the dry distillation step of the waste 1 in the dry distillation furnace 3, high-temperature exhaust gas 16 as hot air generated in the combustion furnace 11 is supplied from the high-temperature exhaust gas recovery line 15 to the hot-air supply line 8.
To indirectly provide external heat of about 500 to 800 ° C. By this carbonization step,
Dry distillation gas 1a which is a combustible gas and char 1 which is a carbide
b is generated.

The char 1b is taken out of the dry distillation furnace 3 through a char take-out line 4, and is separated by a sorter 5 into incombustibles 1c.
Is selectively pulverized, finely pulverized by a pulverizer 6 and then supplied to an activation furnace 7. On the other hand, the carbonized gas 1a is guided to a dust collector 10 through a carbonized gas extraction line 9, and the collected dust 1d is joined to a char extraction line 4 through a dust line 12, and the activated furnace together with the char 1b. 7 is supplied.

Further, the carbonized gas 1a from which dust is collected by the dust collector 10 is guided to the combustion furnace 11 so as to be burned at a high temperature. High temperature exhaust gas 16 generated in the combustion furnace 11
From the hot exhaust gas line 13 to the hot exhaust gas recovery line 1
5 is used as a heat source of the carbonization furnace 3 and is introduced into the activation furnace 7 through the high-temperature exhaust gas introduction line 17 to activate the furnace 7.
And a waste heat recovery boiler 18 downstream
To generate steam 19, and further, the steam 19 generated by the waste heat recovery boiler 18.
Is supplied to the activation furnace 7 through the steam supply line 20 to activate the char 1 b and the dust 1 d with the high-temperature exhaust gas 16 and the steam 19.

As described above, the char 1 is charged into the activation furnace 7 operated by using the high-temperature exhaust gas 16 generated in the combustion furnace 11 as a heat source.
b and dust 1d, and by activating them with steam 19 generated in the waste heat recovery boiler 18,
Activated carbon 21 is obtained.

In the above, the waste 1 is to be treated and can be obtained free or inexpensively, so that the activated carbon 21 can be manufactured at low cost. Therefore, using the obtained activated carbon 21 as a dioxin countermeasure for a bag filter used in various waste treatment processes is extremely advantageous in terms of cost.
Further, as a heat source of the carbonization furnace 3, the high-temperature exhaust gas 1 of the combustion furnace 11 is used.
Since a part of 6 is used, it is also advantageous in that energy can be effectively used.

In the above-described embodiment, the case where the steam 19 generated by the waste heat recovery boiler 18 is used for activating the char 1b has been described. Instead of this, for example, as shown by a two-dot chain line in FIG. 1, a water supply pipe 23 is connected in the middle of the high-temperature exhaust gas introduction line 17 so as to directly enter the high-temperature exhaust gas 16 introduced into the activation furnace 7. Water may be blown to generate steam, and the combustion furnace 11 shown in the above embodiment may be a melting furnace, and other conditions may be used without departing from the scope of the present invention. Of course, various changes can be made.

[0023]

As described above, according to the present invention, the waste is carbonized, and the char of the produced carbonized gas and char is supplied to the activation furnace. An exhaust gas is generated, and a part of the high-temperature exhaust gas is used as a heat source of the activation furnace. Further, steam is generated by recovering waste heat from the remaining portion of the high-temperature exhaust gas. Since there is a method and apparatus for producing activated carbon from waste that activates the char in the activation furnace to produce activated carbon, activated carbon can be produced at low cost using free or inexpensive waste, and therefore, It is extremely advantageous to use the obtained activated carbon for dioxin removal in the waste treatment process, and it is also important to recover waste heat from high-temperature exhaust gas to generate steam. Alternatively, by directly blowing water into the high-temperature exhaust gas supplied as a heat source to the activation furnace to generate water vapor, it can be applied to activation furnaces of different types. By using as a dry distillation heat source, an excellent effect such as effective use of energy can be exhibited.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of an apparatus for producing activated carbon from waste according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Waste 1a Dry distillation gas 1b Char 3 Dry distillation furnace 4 Char removal line 7 Activation furnace 8 Hot air supply line 9 Dry distillation gas removal line 11 Combustion furnace 13 High temperature exhaust gas line 15 High temperature exhaust gas recovery line 16 High temperature exhaust gas 17 High temperature exhaust gas introduction line 18 Waste heat Recovery boiler 19 Steam 20 Steam supply line 21 Activated carbon 23 Water supply pipe

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiro Ito 1 Shinnakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawashima-Harima Heavy Industries Co., Ltd. (72) Inventor Tomoo Ayabe Arata Isogo-ku, Yokohama No. 1 Nakahara-cho Ishi Kawashima Harima Heavy Industries, Ltd. Technical Research Laboratory F-term (reference) 4D004 AA46 BA10 CA26 CA27 CB36 4G046 HA09 HC09 HC16 HC26

Claims (6)

[Claims] Claims 1. A carbonization of waste and a supply of char of a generated carbonization gas and char to an activation furnace, while burning the carbonization gas to generate a high-temperature exhaust gas, and a part of the high-temperature exhaust gas. To be a heat source of the activation furnace, further generate steam by recovering waste heat from the remaining portion of the high-temperature exhaust gas, and activate the char in the activation furnace with the generated steam and the high-temperature exhaust gas A method for producing activated carbon from waste, comprising producing activated carbon. 2. The method according to claim 1, wherein instead of recovering waste heat from the high-temperature exhaust gas to generate steam, water is directly blown into the high-temperature exhaust gas supplied as a heat source to the activation furnace to generate steam. A method for producing activated carbon from the waste according to claim 1. 3. The method for producing activated carbon from waste according to claim 1, wherein a part of the high-temperature exhaust gas is used as a heat source for dry distillation of waste. 4. A carbonization furnace for carbonizing waste to generate carbonization gas and char, an activation furnace for activating the char generated in the carbonization furnace, and a carbonization gas for removing carbonization gas generated in the carbonization furnace. A combustion furnace installed in the removal line, and a high-temperature exhaust gas introduction line connected between the high-temperature exhaust gas line on the exit side of the combustion furnace and the activation furnace to introduce a part of the high-temperature exhaust gas into the activation furnace; And a steam supply line connected between the waste heat recovery boiler installed in the high temperature exhaust gas line on the combustion furnace outlet side and the activation furnace so as to supply steam to the activation furnace. Activated carbon production equipment from waste. 5. Instead of introducing steam generated by a waste heat recovery boiler into an activation furnace, a water supply pipe is connected in the middle of a high-temperature exhaust gas introduction line, and water is directly blown into the high-temperature exhaust gas to generate steam. 5. The apparatus for producing activated carbon from waste according to claim 4, wherein the apparatus is generated. 6. The apparatus for producing activated carbon from waste according to claim 4, wherein a high-temperature exhaust gas recovery line branched from the high-temperature exhaust gas line is connected to the dry distillation furnace.