JP2002356319A - Porous and active carbon material and its producing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a porous and active carbonized material having an adsorptivity at a practical level and of which the raw material is chicken or livestock excrement, and provide its producing method excellent in productivity and energy saving. SOLUTION: The porous and active carbonized material is obtained by carbonization and activation treatment of chicken or livestock excrement. It is produced by such a method that the chicken or livestock excrement is heated to high temperature, carbonized in a carbonization furnace and finally activated using steam. The porous and active carbonized material having whole adsorptivity of almost half of commercial activated carbon from wood can be used practically for decoloration of livestock sewage or deodorization of livestock house or compost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a porous activated carbon having good adsorptive power from chicken dung or animal dung and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, chicken manure and animal manure are dried to be used as fertilizer, or are composted and used for soil improvement. However, the amount of poultry manure and livestock manure discharged from large-scale poultry farms and livestock farms is extremely large, and effective treatment methods and utilization methods are required. As an example of the treatment method, it is conceivable to incinerate chicken dung or the like, but this does not enable effective utilization of chicken dung or the like, and there is also a risk of generating toxic substances such as dioxin by incineration.

[0003]

As a result of repeated studies on the effective use of chicken dung and animal dung, carbonization and activation treatment of chicken dung and animal dung did not produce toxic substances such as dioxin, and did not lead to practical use. A value-added porous activated carbide with a possible level of adsorption is obtained, for example,
For decolorization of livestock sewage, for deodorization of livestock barn and compost, for adsorption of dioxin discharged from incineration plants for municipal waste, etc.
The inventors have found that the present invention can be put to practical use for various other uses, and have completed the present invention.

That is, the present invention is to provide a porous activated carbon having a practical level of adsorption power from chicken dung and animal dung as a raw material, and to provide a method for producing the same, which is excellent in productivity and energy saving. It is an object.

[0005]

Means for Solving the Problems In order to achieve the above object, the porous activated carbon of the present invention is characterized in that chicken or animal manure is carbonized and activated, and the production method of the present invention comprises: It is characterized in that chicken manure or animal manure is heated to a high temperature in a carbonization furnace and carbonized, and at the end of the carbonization processing, a carbide is activated with steam.

[0006] Commercially available woody activated carbon contains about 99% by weight of carbon and other combustibles, and has a low ash content of about 1% by weight.
Because of its large specific surface area and total pore volume, it has excellent adsorption power. On the other hand, the porous activated carbon of the present invention using chicken dung or animal dung as a raw material has a carbon and other combustible components of 70 to 75.
% By weight, and the ash content is about 25 to 30% by weight, which is much higher than that of woody activated carbon, so that the pH is high, and the specific surface area and total pore volume are smaller than woody activated carbon. For this reason, the adsorption power of the activated carbon of the present invention is not as large as that of commercially available woody activated carbon. It is more than half of woody activated carbon and is at a level that can be used sufficiently.

[0007] In addition, as in the production method of the present invention, when chicken manure and the like are carbonized in a carbonization furnace and the carbide is activated with steam at the end of the carbonization, a value-added material having a practical level of adsorption power is obtained. It is possible to easily and efficiently produce a certain porous activated carbide, and to activate the carbide (base ash) obtained by carbonization as in the case where carbonization and activation are separated and performed separately. Since it is no longer necessary to heat to a high temperature again, energy saving can be achieved and productivity is improved.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic explanatory view of an external heat rotary kiln which is an example of a carbonization furnace used in the production method of the present invention.

In this external heat rotary kiln, a retort 1 is provided so as to penetrate into a furnace. Both ends of the retort 1 are supported by support rollers 2 and 2, and one indicator roller 2 is driven by a motor M. When rotated, the retort 1 rotates. The retort 1 is inclined so as to gradually lower from one end where the raw material inlet 1a is located to the other end where the outlet 1b is located. When the retort 1 rotates as described above, the retort 1 is charged into the inside of the retort 1. The raw material 3 is transferred little by little toward the outlet 1b at the other end. A screw 1c for transferring the raw material is built in the raw material inlet 1a. When the screw 1c is rotated by the motor M, the raw material 3 is fed into the retort 1. The retort 1 may be installed horizontally without being inclined, and a spiral strip (not shown) for transferring the raw material may be provided on the inner peripheral surface of the retort 1 to transfer the raw material 3.

In this retort 1, a substantially one-third region on one end side of the raw material charging port 1 a has a heating and heating region for heating and raising the raw material 3, and a substantially one-third region in the center carbonizes the raw material. An approximately 1/3 region on the other end side where the carbonization region and the outlet 1b are located is an activation region where the activation process is performed with water vapor.
Then, a steam supply pipe 4 is inserted into the activation treatment area on the other end side of the retort 1, and steam for activation treatment is supplied from a large number of discharge holes formed in the supply pipe 4. .

The carbonized gas taken out from the carbonized gas outlet 1d at the other end of the retort 1 is supplied to a combustor 5, mixed with air supplied from a fan F, and burned by an auxiliary burner 5a. It has become so. The generated hot air is introduced into the furnace from an inlet 1e of the furnace wall, and the temperature of the furnace is maintained at a high temperature by the hot air. Further, the hot air in the furnace is discharged from an exhaust port 1f. It is emitted as waste gas.

The method for producing a porous activated carbide according to the present invention comprises:
The external heating rotary kiln capable of continuously performing the carbonization treatment and the activation treatment is used in the following manner.

After the auxiliary burner 3 of the combustor 5 is ignited in advance and hot air is sent into the furnace to raise the temperature in the furnace, chicken or animal manure is fed as raw material 3 from the raw material inlet 1a at one end of the retort with the screw 1c. It is continuously fed into the retort 1. As the chicken dung of the raw material 3, the water content is about 30% by weight,
Dried powdered chicken manure having a composition of about 20% by weight of ash, about 31% by weight of carbon and about 19% by weight of other combustible components is suitably used, but fermented chicken manure is also used. In addition, as the raw animal dung, powdery dried dung or fermented dung is used.

The raw material 3 such as chicken dung and the like introduced into the retort 1 is carbonized in a heating and heating region at one end of the retort 1 while being gradually transferred toward the other end as the retort 1 rotates. The temperature is increased to a temperature suitable for the retort 1 and further carbonized in a carbonized region in the center of the retort 1 to completely remove moisture. At this time, the dry distillation gas generated by the thermal decomposition of the raw material 3 such as chicken dung is sent from the dry distillation gas outlet 1d to the combustor 5 and burned as described above, and the hot air is introduced into the furnace. 1 is maintained at a temperature suitable for carbonization and subsequent activation.

The temperature suitable for the carbonization treatment is 800 ° C. or higher, preferably about 830 ° C., and the treatment time is about 30 minutes. When carbonization is performed at a temperature lower than 800 ° C., for example, at a temperature of about 700 ° C., the activated carbon becomes slightly inferior in adsorbing power, as evidenced by experimental data described later.

The carbonized raw material 3 (ash) is continuously transferred to the activation treatment area at the other end of the retort 1 while being further heated, and is activated by contact with the steam supplied from the steam supply pipe 2. , Porous activated carbide 30 having adsorptive power
Is taken out from the outlet 1b. The porous activated carbide 30 has an average particle size of 1 if necessary.
It is pulverized into powder having a size of not more than mm to obtain a product. When the activation treatment is continuously performed at the end of the carbonization treatment in this way, the carbonization (ash) obtained by the carbonization treatment is performed as in the case where the carbonization treatment and the activation treatment are separated and performed separately in the carbonization furnace and the activation furnace. ) Does not need to be heated again to a high temperature when performing the activation treatment, so that energy saving can be achieved and productivity is also improved.

The activation treatment with steam is desirably performed at a temperature higher than the carbonization treatment temperature, for example, about 900 ° C., and the treatment time is about 30 minutes. Further, the amount of steam to be supplied is desirably within a range of 1 to 1.5 weight ratio of steam to 1 carbonized raw material (base ash).
If the amount of water vapor is below the above range, the activation becomes insufficient, causing a disadvantage that the adsorptive power of the obtained activated carbide is reduced, and conversely, even if an amount of water vapor exceeding the above range is supplied, It is wasteful because there is no corresponding improvement in the activation effect.

The processing time of the carbonization treatment and the activation treatment is about 30 minutes as described above, so that the raw material 3 passes through the carbonization treatment area and the activation treatment area of the retort 1 in about 30 minutes, respectively. It is necessary to adjust the transfer speed of Step 3.

Since the porous activated carbon 30 of the present invention obtained by the above-described production method uses chicken dung or animal dung as a raw material, carbon and other combustibles are smaller than those of wood-based activated carbon and are 70 to 7 times.
On the other hand, the ash content is about 25 to 30% by weight, which is much higher than that of the woody activated carbon, so that the pH is high, and the specific surface area and the total pore volume are smaller than the woody activated carbon. Therefore, the adsorptive power of the activated carbon 30 of the present invention is not as large as that of the commercially available woody activated carbon. Yes, it is at a level that can be used sufficiently. Therefore, the activated carbon of the present invention can be used for decolorization of livestock sewage, deodorization of livestock barn and compost, and other various uses.

Next, a description will be given of a test for the adsorption power of the porous activated carbide of the present invention.

(Preparation of sample) Dry chicken manure (water content: 30% by weight) was carbonized at 830 ° C for 30 minutes using the above-mentioned external heat rotary kiln, and continuously at 900 ° C for 30 minutes.
The porous activated carbide obtained by the steam activation treatment for 1 minute (amount of steam: 1: 1) is pulverized, sieved with a 46 μm sieve (330 mesh pass) specified in JIS Z8801, and dried in a thermostatic drier. A powder of a porous activated carbide was prepared as Sample A.

The porous activated carbon obtained by carbonizing at 700 ° C. for 30 minutes in a carbonizing furnace and further activated by steam at 900 ° C. for 60 minutes in another activation furnace is similarly ground and sieved. Separately, a dried product was prepared as a comparative sample B, and a dried product of commercially available woody activated carbon was prepared as a comparative sample C.

(Test Method) JIS K
Based on the activated carbon test method of 1474, iodine and methylene blue were adopted as adsorption solutes, and from the graphs of the respective adsorption isotherms, the adsorption amount when the iodine residual concentration was 2.5 g / l and the methylene blue residual concentration were 0%. .24 mg / l
The iodine adsorption power and the methylene blue adsorption power were evaluated by obtaining the adsorption amount at the time of the above. In addition, livestock sewage was similarly tested, and the absorbance reduction rate was determined to evaluate the livestock sewage adsorption power of Sample A, and the COD removal rate was also determined.

For comparison, iodine adsorption power, methylene blue adsorption power, livestock sewage adsorption power, and COD removal rate were similarly determined for the above comparative sample B and comparative sample C.

(Test Results) As shown in Table 1 below, Sample A comprising the activated carbide of the present invention had an iodine adsorption power of 1
620 mg / g, which is approximately 1.6 times the iodine adsorption capacity (1000 mg / g) of Comparative Sample C made of commercially available woody activated carbon. And this sample A
Has a methylene blue adsorption power of less than 52 mg / g, which is about 35% of the methylene blue adsorption power (150 mg / g) of the comparative sample C, while the livestock sewage adsorption power of the sample A is 0.1%.
At 98, the livestock sewage adsorption power of the comparative sample C (0.368)
And the COD removal rate of sample A was 3%.
At 3.4%, the COD removal rate of the comparative sample C (57.6)
%). From these results, the sample A comprising the activated carbon of the present invention has a total adsorption performance of about half that of the comparative sample C comprising the commercially available woody activated carbon, decolorizing livestock sewage, deodorizing livestock barn and compost, It turns out that it can fully be used for various other uses.

On the other hand, as shown in Table 1 below, a comparative sample B made of activated carbide obtained by performing a carbonization treatment at 700 ° C. and activating in another activation furnace has an iodine adsorption power of 3%.
37 mg / g, methylene blue adsorption power is less than 17 mg / g, livestock sewage adsorption power is 0.17 mg / g, COD removal rate is 17.6%, and overall adsorption performance is inferior to sample A of the present invention. I have. This is because the carbonization temperature is 700 ° C
This is considered to be caused by the fact that carbonization treatment and activation treatment are performed separately.

[0028]

[Table 1]

[0029]

As is clear from the above description, the porous activated carbon of the present invention using chicken dung and animal dung as raw materials has an overall adsorption performance of about half that of commercially available woody activated carbon, It can be sufficiently used for decolorization, deodorization of livestock and compost, and other various uses. The production method of the present invention has an effect of achieving mass production with high productivity while achieving energy saving.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of an external heat rotary kiln used in a production method of the present invention.

[Description of Signs] 1 retort 1a raw material input port 1b take-out port 1c screw 1d dry distillation gas take-out port 1e intake port 1f exhaust port 2 support roller 3 raw material (chicken manure or animal manure) 4 steam supply pipe 5 combustor 30 porous activated carbon

Continued on the front page (72) Inventor Tamotsu Uenaka 2-3-3 Showa-cho, Abeno-ku, Osaka-shi, Osaka Inside Mori Plant Co., Ltd. (72) Inventor Tomoaki Takamatsu 225 Heiwacho, Izumi-shi, Kagoshima Marui Agriculture F-term in the cooperative (reference) 4G046 HA09 HC09 4G066 AA05B AA14D AC39A FA18 FA23 4H012 HA03

Claims (2)

[Claims] A porous activated carbon obtained by carbonizing and activating chicken dung or animal dung. 2. A method for producing a porous activated carbon, comprising heating chicken poultry manure or animal manure to a high temperature in a carbonization furnace and carbonizing the same, and activating the carbide with steam at the end of the carbonizing treatment.