JP4225218B2 - Coke oven discharge by-product with low noise - Google Patents

Description

  The present invention relates to a coke oven discharge by-product that burns the by-product by injecting combustion air into and above the riser when the amount of dry distillation by-products discharged from the coke oven is diffused into the atmosphere from the upper part of the riser. The present invention relates to a biological treatment method, and particularly to a treatment method with low noise.

In the operation of the coke oven, byproducts such as hydrogen, gas mainly containing methane, and tar remaining in the carbonization chamber are released into the atmosphere at the end of dry distillation. Since these by-products come into contact with air at the outlet of the ascending pipe, are ignited and burned, and are converted into combustion products such as CO ₂ and H ₂ O, there is usually no environmental problem.

  However, depending on the combustion conditions, there is a risk that a part of the by-product is diffused into the atmosphere without being burned and accumulated, which is not preferable from the viewpoint of protecting the global environment.

  For this reason, for example, in Patent Document 1, when a carbonization byproduct is released into the atmosphere from the upper part of the riser of the coke oven, an oxygen-containing gas is added to the inside of the riser, or oxygen is further added at the upper part of the outlet of the riser. A coke oven discharge by-product treatment method is disclosed in which a contained gas is added to improve combustibility and reduce unburned by-products. Patent Document 2 shows the optimum conditions for adding the oxygen-containing gas, wherein the elevation angle and normal angle of a plurality of nozzles provided above or above the riser tube are within a predetermined range, and the oxygen-containing gas to be added is added. A method has been proposed in which the total oxygen amount is 0.1 to 0.8 times the stoichiometric amount required for the oxidation reaction with dry distillation by-products discharged from the upper part of the riser.

  According to these conventional processing methods, it is possible to suppress the by-products discharged from the ascending pipe of the coke oven from being released into the atmosphere without being burned. However, since the blowing of oxygen-containing gas (for example, combustion air) is forcibly performed, when combustion air is simultaneously blown into the dry distillation by-products discharged from the upper part of the riser pipe, There is a possibility that noise pollution may be caused in a location where the blowing noise (blowing noise from the blowing nozzle) and combustion noise are very loud and the coke oven is close to commercial or residential areas. .

  In the above-mentioned patent document, from the viewpoint of preventing the emission of unburned by-products into the atmosphere, an efficient method of injecting oxygen-containing gas into the upper part and inside of the riser is described. There is no description of noise suppression at that time. However, from the viewpoint of noise suppression, there is a need for countermeasures for suppressing blowing noise and combustion noise when combustion air is used as the oxygen-containing gas.

JP 2001-164257 A

JP 2002-201476 A

  The present invention has been made in view of such a situation, and an object of the present invention is to blow combustion air generated when combustion air is blown into a dry distillation by-product to be diffused into the atmosphere from the upper part of a riser pipe of a coke oven. An object of the present invention is to provide a method for treating coke oven exhaust by-products with low noise, which can reduce noise and combustion noise.

  As a result of conducting a combustion test under various conditions in order to solve the above-described problems, the present inventors have found an optimal combustion air blowing method from the viewpoint of noise suppression.

The gist of the present invention resides in the following method for treating coke oven discharge by-products.
"The riser carbonization from above by-products of the coke oven during operation of the air dissipated upon blowing combustion air at the top and inside of the riser, 10 to 50% of the total amount of air blown above the upper, inside A method for treating coke oven discharge by-products with low noise blowing 50 to 90 % of the total amount of air blown. ]
The “upper part of the rising pipe” refers to the vicinity of the outlet of the rising pipe. That is, in addition to the outlet portion of the rising pipe, the lower part of the outlet and the upper part of the outlet are also referred to as “upper part of the rising pipe”. Further, “inside the riser pipe” refers to a region from the middle part of the riser pipe to the base part (a part directly above the connection part with the carbonization chamber, that is, a part A in FIG. 1 described later).

  According to the coke oven discharge byproduct processing method of the present invention, combustion air is blown into the dry distillation byproduct to be released into the atmosphere from the upper part of the ascending pipe of the coke oven and burned. Noise and combustion noise (that is, noise during combustion processing) can be suppressed.

  Hereinafter, after specifically describing the generation state and processing state of by-products discharged from the coke oven, the processing method with less noise according to the present invention will be described.

  When coal is charged into the coking chamber of the coke oven, the temperature of the coal rises due to heat transmitted through the bricks from the combustion chambers adjacent to both sides of the coking chamber. As the temperature rises, the generation of volatile components such as gas and tar becomes prominent, and these by-products pass through the riser from the space above the carbonization chamber and are collected in the gas collection main and sent to the downstream separation and purification process. It is done.

  FIG. 1 is a longitudinal sectional view illustrating a rising pipe through which the by-produced gas, tar and the like pass and a portion adjacent thereto. As shown in the figure, the ascending pipe 1 is connected to the gas collecting main pipe 3 via the dish valve 2, and the lower end communicates with the carbonization chamber 4. A canopy 5 is attached to the upper end of the riser 1 so as to be opened and closed as indicated by an arrow. The upper part of the carbonization chamber 4 has a heat-insulating brick 6 structure, and coal inlets 7 having lids are provided at four to five locations.

  The width of the carbonization chamber is around 450 mm, and the coal charged in the carbonization chamber of this width is heated by heat transfer (mainly conduction heat transfer) from the combustion chambers on both sides adjacent to the carbonization chamber. For this reason, the rate of temperature rise is small, and it takes about a day and a night for the center portion (the middle portion of charcoal) to be baked to about 1000 ° C. That is, since the region of about 400 ° C. where generation of volatile components such as gas and tar becomes remarkable moves from the furnace wall side to the middle part of the coal at a speed of 10 mm / h, the furnace wall side of the carbonization chamber moves to the middle part of the coal. There is always a temperature gradient.

  Therefore, carbonization byproducts such as gas and tar are constantly generated throughout the entire period of carbonization treatment.

  Furthermore, the coke oven carbonization chamber has a length of about 15 m and a height of around 6 m, so it is not easy to heat this vast surface uniformly. Of the coal charged in the carbonization chamber due to the fact that it has a taper of about 60 mm and the heat radiation is inevitably large at both ends in the furnace length direction where the furnace lid is installed. Is not necessarily uniform. For this reason, even when coke is discharged after the end of dry distillation, the progress of dry distillation is locally delayed, and there is a high possibility that a part where by-products are generated remains.

  Thus, at the end of dry distillation in which by-products continue to be generated, the dish valve 2 shown in FIG. 1 is closed, the canopy 5 of the riser 1 is opened, and the riser 1 and the air collecting main 3 When the communication with the pipe is cut off (cut off), the carbonization by-product discharged from the coke oven is discharged from the canopy 5 of the riser 1 into the atmosphere.

  These by-products come into contact with the air as they exit the riser, so they ignite spontaneously when the gas temperature is high. If it is not ignited, it is ignited with a seed igniter or the like attached near the outlet of the riser. Therefore, as described above, most of the combustible components burn and disappear, but the combustion state is not appropriate, and if some of the combustible components remain unburned, they are directly diffused into the atmosphere. Therefore, a nozzle is provided in the ascending pipe, and combustion air is forcibly blown into or inside the ascending pipe, and the combustible component of the by-product is burned and rendered harmless.

The present invention is a method for suppressing the blowing sound and combustion noise caused by the forced blow-in of combustion air when treating the carbonization by-product in this way. When the combustion air is blown into the upper part and the inside of the riser pipe during the operation of releasing dry distillation by-products from the atmosphere, 10 to 50% of the total amount of air to be blown is introduced into the upper part, and ~ Method of blowing 90 % ". The “total amount of air to be blown” is the total amount of combustion air necessary to burn dry distillation by-products that are released from the upper part of the riser pipe of the coke oven (hereinafter also referred to as “required air amount”).

  In the method of the present invention, when the by-product is combusted, combustion air is blown into the upper part and inside of the ascending pipe, and publicly known means may be used as means for blowing. For example, the means used in the method described in Patent Document 1 mentioned above, that is, an oxygen-containing gas is added to the inside of the riser, or an oxygen-containing gas is further added at the upper part of the outlet of the riser to improve the combustibility. The method to do is applicable. Usually, it is better to blow using a nozzle, and the blow nozzle 8 is also used in the example shown in FIG.

In this way, when the combustion air is blown into the upper part and the inside of the riser and burned, the method of the present invention is such that “the upper part (the upper part of the riser) has 10 to 50% of the total amount of air to be blown in. , 50 to 90 % of the total amount of air to be blown is blown into the inside (inside the rising pipe).

  The above-mentioned “upper pipe upper part” means the lower part of the outlet and the upper part of the outlet in addition to the outlet part of the rising pipe. In the example shown in FIG. 1, the upper nozzles 8a and 8b respectively cause It is configured to blow combustion air. Further, “inside the riser pipe” means between the middle part and the base part of the riser pipe, and in the example shown in FIG. 1, combustion air is blown into the middle part of the riser pipe using the internal nozzle 8c. it can.

The reason why 10 to 50% of the total amount of air to be blown into the upper part of the riser pipe and 50 to 90 % to be blown into the inside is as follows. If it exceeds 50%, the noise level exceeds 85 dB, which is undesirable.

Inner surface of the Noboru Ue pipe has a soundproof because lining lined with refractory are subjected, is hindered propagated to the outside of the jet noise and combustion noise caused by the blowing of the combustion air, increased noise level Is suppressed. However, the amount of combustion air blown into the riser is limited by the inside diameter of the riser, so that up to that limit, the internal blow nozzle is used to blow the riser into the riser, and there is a shortage of the required amount of air. Is preferably blown into the upper part of the riser with the upper blowing nozzle.

  By using such a combustion air blowing method, during the operation of releasing carbonization by-products from the upper part of the riser pipe of the coke oven, that is, from the end of the carbonization to the start of coal charging for the next charge, In addition, the noise generated during the combustion process can be suppressed.

  FIG. 2 is a conceptual diagram of an experimental apparatus simulating a carbonization chamber and a riser pipe. This apparatus has a riser 9, a mixer 10 for mixing simulated coke oven gas and benzene simulating tar components, and a preheater 11 for preheating the mixed gas (that is, simulated dry distillation gas), Premixed air (that is, combustion air) is blown into the inside of the riser 9 by an internal blow nozzle (not shown), and the riser pipe is connected to the riser pipe 12 (air blow nozzle) having a ring-shaped slit nozzle. Combustion air is blown into the upper portion of 9. In addition, benzene is heated with the heater 13 and is sent to the mixer 10 as a vapor | steam.

A mixed gas (H ₂ : 55 vol%, CH ₄ : 25 vol%, C ₂ H ₄ : 5 vol%, and N ₂ : 15 vol%) prepared as a simulated coke oven gas using the experimental apparatus shown in FIG. ) And benzene as a simulated substance of the tar component were mixed in a mixer 10 so that the benzene content was about 0.1 mol%.

  Table 1 shows the composition of the mixed gas. This composition is an analysis result of “inlet sample gas” (see FIG. 2) collected on the inlet side of the riser 9.

  First, after the premixed gas is preheated to 300 ° C. by the preheater 11, the mixed gas is introduced into the riser 9, and the premixed air is not blown into the riser 9. 12 (air blowing nozzle) was used to blow combustion air (elevation angle θ: 30 degrees), and the mixed gas was burned. The air ratio is changed in the range of 0 (when combustion air is not blown) to 1.0, and the “exit sample gas” (see FIG. 2) collected after the combustion process is analyzed for the combustible gas concentration. At the same time, noise measurement was performed during the combustion process. An igniter 14 was used for ignition of the mixed gas. In addition, the noise measurement is performed using a normal sound level meter stipulated in JIS C 1502 at each measurement point 1 m away from the air diffuser 12 on the cross-directional line on the horizontal plane starting from the center of the upper opening of the riser 9. (4 points in total), and the maximum value was evaluated as a representative value.

  The test results are shown in Table 2.

  As is clear from the results shown in Table 2, the combustible gas concentration decreases with increasing air ratio, and most of the combustible gas burns at air ratios of 0.8 (Example 5) and 1.0 (Example 6). did. However, at an air ratio of 1.0 in Example 6, the noise level from the air blowing nozzle exceeded 100 dB, and there was a problem in noise.

  Next, after the premixed gas is preheated to 300 ° C. by the preheater 11, it is introduced into the ascending pipe 9, and combustion air is blown using the upper blowing nozzle (elevation angle θ: 30 degrees) and the internal blowing nozzle together. Then, the mixed gas was combusted, and the concentration of combustible gas was analyzed and the noise was measured. The distribution ratio of the blowing amount from the upper blowing nozzle and the internal blowing nozzle (hereinafter referred to as “air blowing ratio” or simply “blowing ratio”) is 50%, and the air ratio is 0.1 to 1 It was changed in the range of 0.0.

  The test results are shown in Table 3. Both correspond to examples of the present invention.

  As shown in Table 3, by blowing the combustion air into the upper part and the inner part of the riser, the ratio of the air to be blown (the sum of the blown air ratio from the upper part and the blown air ratio into the interior) ), The combustible gas concentration in the exhaust gas was reduced as compared with the case where the air injection shown in Table 2 was performed only at the upper part of the riser. When the air ratio was 1.0 (comparison between Example 6 in Table 2 and Invention Example 4 in Table 3), the noise level was also clearly reduced.

  FIG. 3 illustrates the results shown in Tables 2 and 3. The noise level is clearly reduced when the upper and lower parts are blown simultaneously.

  Further, after the mixed gas is preheated to 300 ° C. by the preheater 11, it is introduced into the riser 9, and when the combustion air is blown using the upper blowing nozzle (elevation angle θ: 30 degrees) and the internal blowing nozzle together. , The blowing air ratio is set to 1.0, the air blowing ratio from the upper blowing nozzle and the internal blowing nozzle is changed, the mixed gas combustion treatment is performed, and the combustible gas concentration analysis and noise measurement are performed. did.

  The test results are shown in Table 4. In the column of “Noise judgment” in Table 4, “◯” indicates that the noise level is 85 dB or less, and “X” indicates that it exceeds 85 dB.

  From the result shown in Table 4, the noise level was low and the noise suppression effect was recognized, so that the blowing ratio from an internal blowing nozzle was large.

  FIG. 4 illustrates the results shown in Table 4, but the above effects are obvious. Although the noise regulation conditions differ depending on the coke oven location conditions, the upper limit value of the noise level in the factory premises is shown as 85 dB in the figure.

From FIG. 4, it can be read that the lower limit of the blow ratio from the internal blow nozzle is 50%. That is, in order to satisfy the control upper limit value of the noise level, the amount of combustion air blown from the internal blow nozzle is 50 to 90 % (therefore, the blow amount from the external blow nozzle is 50 to 10 %). )And it is sufficient.

  According to the low noise coke oven discharge by-product processing method of the present invention, it is possible to suppress the emission sound and combustion noise from the air blowing nozzle during the combustion process of dry distillation by-products that are diffused into the atmosphere from the upper part of the riser pipe of the coke oven. Is possible. Therefore, this method can be applied during an operation in which dry distillation by-products are diffused into the atmosphere from the upper part of the ascending pipe of the coke oven, and noise generated at that time can be suppressed to contribute to environmental conservation.

It is a longitudinal cross-sectional view which illustrates the ascending pipe through which the gas by-produced at the time of dry distillation, tar, etc. pass, and the part adjacent to it. It is a conceptual diagram of the experimental apparatus which simulated the carbonization chamber and the riser pipe. It is a figure which shows the relationship between the air ratio of the combustion air which blows into the upper part of a riser pipe | tube, and a noise level as a result of an Example. It is a figure which shows the relationship between the internal nozzle blowing ratio and the noise level of the combustion air which blows into the upper part of a riser pipe | tube and the inside as a result of an Example.

Explanation of symbols

1: riser pipe 2: dish valve 3: air collection main pipe 4: carbonization chamber 5: canopy 6: heat insulating brick 7: coal inlet 8: blowing nozzle 8a, 8b: upper nozzle 8c: internal nozzle 9: riser pipe 10 : Mixer 11: Preheater 12: Air diffuser 13: Heater 14: Igniter

Claims (1)

The carbonization products from the riser top of the coke oven during operation of the air dissipated upon blowing combustion air top of the riser and therein, 10 to 50% of the total amount of air blown above the top, the inside A method for treating coke oven discharge by-products with low noise, characterized in that 50 to 90 % of the total amount of air to be blown is blown.

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