JP3494216B2 - Recovery and utilization method of activated carbon in sintering exhaust gas treatment equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sintering process capable of effectively recovering and reusing a reusable size product in order to prevent waste of the use of activated carbon in an activated carbon moving bed type dry desulfurization and denitration apparatus. The present invention relates to a method of collecting and utilizing activated carbon in an exhaust gas treatment device.

[0002]

2. Description of the Related Art An active carbon moving bed type dry desulfurization denitration device has been conventionally known as a device for treating exhaust gas from a sintering machine of an iron mill. In this activated carbon moving bed type sintering exhaust gas treatment apparatus, after the product activated carbon of a certain size is received by the receiving hopper, the exhaust gas is processed while circulating the adsorption tower and the desorption tower. In this case, the used activated carbon is sieved and the activated carbon powder particles that have become less than a predetermined particle size due to wear are air-transported with a dust blower along with the activated carbon dropped from a conveyor, etc., and collected by a cyclone, a dust precipitator, etc. Finally, it is stored in a dust tank, and fine dust activated carbon etc. generated at the time of receiving the receiving hopper and at the transportation stage is also pneumatically transported by a dust blower and collected by a cyclone and a dust collector. It is stored in a dust tank.

On the other hand, since activated carbon is expensive, recycling the activated carbon without waste leads to a reduction in running cost of the sintering exhaust gas treatment apparatus. Therefore, the present inventors reviewed the flow path of the activated carbon in the sintering exhaust gas treatment device to check whether there is any waste, and the activated carbon particles collected by the cyclone and the activated carbon powder have a relatively small particle size. It was found that a product with a size close to the product activated carbon was mixed. Therefore, it has been desired to develop a method capable of reliably collecting and effectively reusing a product having a size close to that of the product activated carbon.

[0004]

SUMMARY OF THE INVENTION The present invention was developed to meet the above demands, and collects activated carbon particles collected by a cyclone and product activated carbon contained in activated carbon powder without waste. The present invention has been completed for the purpose of providing a method for recovering and utilizing activated carbon in a sintering exhaust gas treatment apparatus, which can effectively reuse the same and reduce the running cost.

[0005]

The method for recovering and utilizing activated carbon in the sintered exhaust gas treatment apparatus of the present invention made to solve the above-mentioned problems is as follows: Activated carbon received in the receiving hopper is activated carbon moving bed type dry desulfurization denitration. Introduced into the equipment and used for the treatment of sintering exhaust gas, of this activated carbon, the product-sized activated carbon is circulated and used, while the worn activated carbon with a reduced particle size is stored in a dust tank during the sintering exhaust gas treatment. , A cyclone installed on the inlet side of the dust tank collects activated carbon of a certain size or more and conveys it to the receiving hopper side, and the activated carbon of the product size is separated by the gravity drop method at the inlet of the receiving hopper and received. It is characterized in that it is collected in a hopper and used for reuse.

Further, the separation of activated carbon by the gravity drop method
The invention according to claim 2, wherein adjustment is made by the suction air flow rate by an outside air suction pipe provided in the vicinity of the receiving hopper of the conveying pipe connecting the cyclone and the receiving hopper,
Of the activated carbon separated by the gravity drop method, the product-sized activated carbon is collected in the receiving hopper, and the smaller-sized activated carbon is transported to the dust collector to be separated and collected. .

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the drawings. The drawing shows the case where the exhaust gas from the sintering machine of the steel mill is treated by the activated carbon moving bed type dry desulfurization and denitration device. After receiving the product activated carbon having a certain size in the receiving hopper 1, the dry type not shown Through the desulfurization and denitration apparatus, the exhaust gas is treated while further circulating the adsorption tower and the desorption tower. In this case, the finely powdered activated carbon powder, which has been consumed and has become smaller than a predetermined particle size, is classified by a sieve and is pneumatically transported by the dust blowers 2 and 2 together with the activated carbon dropped from a conveyor or the like, and is also cyclone 3 and the dust collector 4. It is collected by 4 and finally stored in the dust tank 5. Further, in the dust tank 5, fine powder activated carbon and the like generated at the time of receiving the receiving hopper and at the transportation stage are also pneumatically transported by the dust-proof blower in the same manner as described above, sorted by the cyclone and the dust collector and stored in the dust tank. ing.

[0008] Here, the present inventors checked whether waste of activated carbon was generated in the flow path in the above-mentioned sintering exhaust gas treatment device, and found that the activated carbon particles and activated carbon collected by the cyclone 3 were It was discovered that powder with a relatively large particle size and a size similar to that of the product activated carbon was mixed in the powder, leading to the completion of a method for reliably recovering the size of this product activated carbon and effectively reusing it. It was. That is, the activated carbon separated by the cyclone 3 installed in the dust tank 5 is conveyed to the receiving hopper 1, and only the activated carbon of the product size (particle size of about 9.0 mm or more) is separated by gravity drop and separated. The product-sized activated carbon is collected in the receiving hopper 1 for reuse.

More specifically, the cyclone 3 has:
In addition to finely powdered activated carbon powder that is circulated and used in the activated carbon moving bed, dropping activated carbon from a conveyor etc. is also introduced.When centrifugally separated, a relatively large particle size and a size close to the product activated carbon are considerable. Will be collected. Therefore, the lower pipe of the cyclone 3 and the receiving hopper 1 are connected by a conveying pipe 6, and the product activated carbon is sent to the receiving hopper 1 side to separate only the product-sized activated carbon into the receiving hopper 1 by gravity drop. Fine activated carbon and fine dust powder were introduced into the dust collector 4.

The separation of the activated carbon by the gravity drop method is carried out, for example, as shown in FIG. Can be adjusted. That is, since the activated carbon having a relatively large particle size and a size close to that of the product activated carbon is heavier than other fine activated carbon and dust fine powder, the opening degree of the damper 7a is controlled so that only the activated carbon having a large size falls naturally. By adjusting the suction air flow rate, it is possible to introduce only large-sized activated carbon into the receiving hopper 1. The product-sized activated carbon separated by the gravity drop method is collected in the receiving hopper 1, but the other small-sized activated carbon is transported by air flow to the dust collector 4 through the transfer pipe 8 and separated and collected.

As described above, according to the present invention, when the exhaust gas emitted from the sintering machine of the steel mill is treated by the activated carbon moving bed type dry desulfurization denitration apparatus, the activated carbon collected by the cyclone 3 installed in the dust tank 5 is received. After being conveyed to the hopper 1, only the product-sized activated carbon is separated by the gravity drop method at the inlet side, and the separated product-sized activated carbon is collected in the receiving hopper 1 for reuse, so that the activated carbon is not wasted. Since it can be efficiently used without generating it, the running cost can be reduced. Further, since the cyclone 3 and the receiving hopper 1 are simply connected by the transfer pipe 6, and since the gravity drop method is used for the separation of the activated carbon, no special device is required, and the device manufacturing cost can be reduced. It will be.

[0012]

[Example] Exhaust gas discharged from a sintering machine was treated by a dry desulfurization and denitration apparatus of a moving bed type of activated carbon. The treatment conditions are as shown in Table 1, and the transfer amount of activated carbon in the activated carbon moving bed is 1
It is 4.9 tons / hour. For the first 10 days, it was operated as usual, and from the 11th day to the 22nd day, it was operated while separating and collecting activated carbon from the cyclone and reusing it. As a result,
As shown in FIG. 3, the average amount of activated carbon replenished in the conventional example was 3.53 tons / day, but in the present invention, the average amount was 3.
It was 25 tons / day, and it was confirmed that a significant reduction in the amount of activated carbon used could be achieved.

[0013]

[Table 1]

[0014]

As is apparent from the above description, the present invention introduces the activated carbon received in the receiving hopper into the activated carbon moving bed type dry desulfurization denitration apparatus and treats the sintering exhaust gas,
Of these activated carbons, the product-sized activated carbons are reused, while the worn-down activated carbons with reduced particle size are stored in the dust tank. The above activated carbon is separated, collected, and transported to the receiving hopper side.The product-sized activated carbon is separated by the gravity drop method at the inlet of this receiving hopper and collected in the receiving hopper for effective reuse. It is possible to recycle various activated carbons without waste and reduce the running cost. Therefore, the present invention is extremely useful as a method for recovering and utilizing activated carbon in a sintering exhaust gas treatment apparatus that eliminates the conventional problems, and greatly contributes to industrial development.

[Brief description of drawings]

FIG. 1 is an explanatory view of a main part of a sintering exhaust gas treatment apparatus showing an embodiment of the present invention.

FIG. 2 is a front view showing a device for separating activated carbon by a gravity drop method.

FIG. 3 is a graph showing the amount of activated carbon supplied in Examples.

[Explanation of symbols]

1 receiving hopper 3 cyclones 4 dust collector 5 dust tank 6 Transport pipe 7 Outside air suction tube

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI B07B 9/00 C22B 1/20 N C01B 31/08 B01D 53/34 132Z F27B 21/08 ZAB // C22B 1/20 (72) Inventor Masahiko Hamada 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Co., Ltd. Corporate Technology Development Division (72) Inventor Kazutaka Katsurahara 2-1-1 Yatocho, Tanashi City, Tokyo Sumitomo Heavy Industries, Ltd. Tanashi In-house (72) Inventor Hiroki Goto 1-1-1, Yatocho, Tanashi-shi, Tokyo Sumitomo Heavy Industries, Ltd. Inside Tanashi Factory (56) Reference JP-A-11-137945 (JP, A) JP 2001- 170436 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B01D 53/34

Claims (3)

(57) [Claims] 1. Activated carbon received in a receiving hopper is introduced into an activated carbon moving bed type dry desulfurization and denitration apparatus to be used for treatment of sintering exhaust gas. Of the activated carbon, the product-sized activated carbon is circulated and used while having a small particle size. When the waste exhaust activated carbon is stored in a dust tank and treated with sintering exhaust gas,
A cyclone installed on the inlet side of the dust tank collects activated carbon of a certain particle size or more and conveys it to the receiving hopper side,
A method for collecting and utilizing activated carbon in a sintering exhaust gas treatment apparatus, characterized in that product-sized activated carbon is separated by a gravity drop method at the inlet of the receiving hopper and is collected in the receiving hopper for reuse. 2. The firing according to claim 1, wherein the separation of the activated carbon by the gravity drop method is adjusted by the suction air flow rate by an outside air suction pipe provided in the vicinity of the receiving hopper of the conveying pipe connecting the cyclone and the receiving hopper. A method for collecting and utilizing activated carbon in a flue gas treatment device. 3. The firing according to claim 1, wherein small-sized activated carbons other than the product-sized activated carbons separated by the gravity drop method and collected in the receiving hopper are transported to a dust collector to be separated and collected. A method for collecting and utilizing activated carbon in a flue gas treatment device.