JP2002018235A - Method for recovering and utilizing active carbon in apparatus for treating exhaust gas of sintering - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for recovering and utilizing active carbon in an apparatus for treating exhaust gas of sintering by which the active carbon can be effectively recovered and utilized in such a way that the active carbon can be used without waste in an active carbon movable layer type dry desulfurization and denitrification apparatus. SOLUTION: When the exhaust gas of sintering is treated in such a way that the active carbon received in a receiving hopper 1 is introduced into the active carbon movable layer type dry desulfurization and denitrification apparatus to use it for treatment of the exhaust gas of sintering, and among this active carbon, the active carbon with a product size is used by circulation, and on the other hand, worn active carbon with decreased particle sizes is stored in a dust tank 5, the active carbon with a definite particle size or larger is separated and collected by means of a cyclone 3 set on the inlet side of the above dust tank 5, and this is carried to the receiving hopper side and the active carbon with the product size is separated by a gravity falling down method at an inlet of this receiving hopper 1 and is recovered into the receiving hopper and is reused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a sintering method capable of effectively recovering and reusing a reusable size of activated carbon in a dry desulfurization and denitration apparatus of an activated carbon moving bed type so as not to waste it. The present invention relates to a method for collecting and using activated carbon in an exhaust gas treatment device.

[0002]

2. Description of the Related Art Conventionally, an activated carbon moving bed type dry desulfurization and denitration apparatus has been known as an apparatus for treating exhaust gas emitted from a sintering machine at an ironworks. In this activated carbon moving bed type sintering exhaust gas treatment apparatus, after receiving a product activated carbon of a certain size in a receiving hopper, the exhaust gas is treated while circulating through an adsorption tower and a desorption tower. In this case, the used activated carbon is sieved and the activated carbon powder particles having a predetermined particle size or less due to wear are transported by a dust blower together with the activated carbon falling from a conveyor or the like, and are collected by a cyclone, a dust collector, or the like. Finally, it is stored in a dust tank, and in the dust tank, fine activated carbon and the like generated at the time of receiving the receiving hopper or at the transportation stage are also pneumatically transported by a dustproof blower and collected by a cyclone and a dust collector. Stored in a dust tank.

On the other hand, since activated carbon is expensive, circulating the activated carbon without waste leads to a reduction in the 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 apparatus and checked whether there was any waste, and found that the activated carbon particles collected by the cyclone and the activated carbon powder had a relatively large particle diameter. It was found that a large size of the activated carbon was mixed. Therefore, there has been a demand for the development of a method capable of reliably recovering and effectively reusing a product having a size close to the product activated carbon.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been developed to meet the above-mentioned demands, and is intended to collect 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 of recovering and using activated carbon in a sintering exhaust gas treatment apparatus capable of effectively reusing and reducing running costs.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a method for recovering and using activated carbon in a sintering exhaust gas treatment apparatus according to the present invention is described. The activated carbon is introduced into the equipment and treated for sintering flue gas.Of the activated carbon, the activated carbon of a product size is recycled and used, while the activated carbon with reduced particle size is stored in a dust tank for sintering flue gas treatment. Activated carbon having a certain particle size or more is collected by a cyclone installed at the entrance side of the dust tank, and is transported to the receiving hopper side. At the entrance of the receiving hopper, activated carbon of a product size is separated by gravity dropping and received. It is characterized in that it is collected in a hopper and used for reuse.

[0006] Separation of activated carbon by the gravity drop method,
The invention according to claim 2, wherein the transfer pipe is connected to the cyclone and the receiving hopper is adjusted according to a suction air flow rate by an outside air suction pipe provided near the receiving hopper,
The invention according to claim 3, wherein, among activated carbons separated by the gravity drop method, product-size activated carbon is collected in a receiving hopper, and activated carbon of a smaller size is transported to a dust collector and separated and collected. .

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. The drawing shows a case in which exhaust gas emitted from a sintering machine at an ironworks is treated by an activated carbon moving bed type dry desulfurization and denitration apparatus. After receiving a product activated carbon having a fixed size in a receiving hopper 1, a dry type (not shown) is used. Through the desulfurization and denitration apparatus, the exhaust gas is treated while circulating the adsorption tower and the desorption tower. In this case, the finely powdered activated carbon powder that has been consumed and reduced to a predetermined particle size or less is classified by a sieve, transported by the dust blowers 2 and 2 together with the activated carbon falling from the conveyor or the like, and then cyclone 3 and the dust collector 4. , 4 and finally stored in the dust tank 5. Also, in the dust tank 5, fine activated carbon and the like generated at the time of receiving or transporting the receiving hopper are also pneumatically transported by a dust proof blower as described above, classified by a cyclone and a dust collector, and stored in the dust tank. ing.

Here, the present inventors checked whether or not activated carbon was wasted in the flow path in the sintering exhaust gas treatment apparatus as described above. As a result, the activated carbon particles and activated carbon collected by the cyclone 3 were checked. It was found that powder having a relatively large particle size and a size close to that of activated carbon was mixed in the powder, and a method that could reliably collect and effectively reuse this size of activated carbon was completed. It was. That is, the activated carbon separated by the cyclone 3 installed in the dust tank 5 is transported to the receiving hopper 1, and only the activated carbon having a product size (particle diameter of about 9.0 mm or more) is separated by gravity drop and separated. The product-size activated carbon is collected in the receiving hopper 1 and is reused.

More specifically, the cyclone 3 includes:
In addition to the fine powdered activated carbon powder circulated in the activated carbon moving bed, activated carbon falling from a conveyor or the like is also introduced, and when centrifuged, particles with 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 the transport pipe 6, and this product activated carbon is sent to the receiving hopper 1 side, and only the product-size activated carbon is separated by gravity and introduced into the receiving hopper 1, The fine activated carbon and fine dust were introduced into the dust collector 4.

The separation of the activated carbon by the gravity drop method is performed by, for example, as shown in FIG. 2, the suction air flow rate by an outside air suction pipe 7 provided near a receiving hopper of a transport pipe 6 connecting the cyclone 3 and the receiving hopper 1. Can be adjusted. That is, since the activated carbon having a relatively large particle size and a size close to that of a product activated carbon is heavier than other fine activated carbon or 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, only activated carbon having a large size can be introduced into the receiving hopper 1. The product-size activated carbon separated by the gravity drop method is collected in the receiving hopper 1, but other small-sized activated carbon is transported by airflow to the dust collector 4 through the transfer pipe 8 to be separated and collected.

As described above, according to the present invention, when the exhaust gas discharged from the sintering machine of the steel mill is treated by the activated carbon moving bed type dry desulfurization and 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-size activated carbon is separated at the inlet side by the gravity drop method, and the separated product-size activated carbon is collected in the receiving hopper 1 and reused. Since it can be used efficiently without causing the generation, the running cost can be reduced. Further, it is only necessary to connect the cyclone 3 and the receiving hopper 1 with the transfer pipe 6, and the activated carbon is separated by the gravity drop method, so that no special device is required and the production cost of the device can be reduced. It will be.

[0012]

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

[0013]

[Table 1]

[0014]

As is clear from the above description, the present invention introduces activated carbon received in a receiving hopper into an activated carbon moving bed type dry desulfurization and denitration apparatus, and treats the sintered exhaust gas.
Activated carbon of product size is recycled for use while activated carbon with reduced particle size is stored in a dust tank for sintering exhaust gas treatment. The above activated carbon was separated and collected and transported to the receiving hopper side.At the entrance of this receiving hopper, product-size activated carbon was separated by gravity drop method, collected in the receiving hopper, and effectively reused. Activated carbon can be recycled without waste, and running costs can be reduced. Therefore, the present invention greatly contributes to industrial development as a method of recovering and utilizing activated carbon in a sintering exhaust gas treatment apparatus that has eliminated the conventional problems.

[Brief description of the 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 an apparatus for separating activated carbon by a gravity drop method.

FIG. 3 is a graph showing the amount of activated carbon replenishment of an example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving hopper 3 Cyclone 4 Dust collector 5 Dust tank 6 Transport pipe 7 External air suction pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B07B 9/00 C22B 1/20 N C01B 31/08 B01D 53/34 132Z F27B 21/08 ZAB // C22B 1 / 20 (72) Inventor Koichi Takatani 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division (72) Inventor Masahiko Hamada 20-1 Shintomi, Futtsu-shi, Chiba Japan Nippon Steel Corporation In the headquarters (72) Kazutaka Katsurahara 2-1-1 Tanidocho, Tanashi-shi, Tokyo Sumitomo Heavy Industries, Ltd.Tanashi Factory (72) Inventor Hiroki Goto 2-1-1 Tanidocho, Tanashi-shi, Tokyo Sumitomo Shigeto Machinery Co., Ltd. Tanashi Factory F-term (reference) 4D002 AA02 AA12 AC02 BA04 CA08 DA41 EA07 GA03 GB12 4D021 FA12 FA25 GA16 GB03 HA10 4G046 HC14 4K001 AA10 CA44 GA10 GB09

Claims (3)

[Claims] 1. Activated carbon received in a receiving hopper is introduced into an activated carbon moving bed type dry desulfurization and denitration apparatus and subjected to sintering exhaust gas treatment. Among the activated carbon, activated carbon having a product size is circulated and has a small particle size. When performing the sintering exhaust gas treatment by storing the lost wear activated carbon in a dust tank,
Activated carbon of a certain particle size or more is collected by a cyclone installed on the entrance side of the dust tank, and is transported to the receiving hopper side.
A method for recovering and using activated carbon in a sintering exhaust gas treatment apparatus, wherein activated carbon of a product size is separated at the entrance of the receiving hopper by a gravity drop method, collected in a receiving hopper and reused. 2. The sintering apparatus according to claim 1, wherein the separation of the activated carbon by the gravity drop method is adjusted by a suction air flow rate of an outside air suction pipe provided near a receiving hopper of a transport pipe connecting the cyclone and the receiving hopper. A method for collecting and using activated carbon in a sewage gas treatment device. 3. The firing method according to claim 1, wherein the small-sized activated carbon other than the product-size activated carbon separated by the gravity drop method and collected in the receiving hopper is transported to a dust collector and separated and collected. A method for collecting and using activated carbon in a sewage gas treatment device.