JP2013142090A - Method and apparatus for producing formed coke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for producing formed coke, which eliminate the use of a heating device for high temperature carbonization gas, suppresses breaking of formed coke, and can prevent the yield of a formed coke product from lowering.SOLUTION: A part of a coolant gas introduced into the cooling zone 2c of a carbonization furnace 2 is drawn from an outlet 22 and fed as low temperature carbonization gas into the low temperature carbonization zone 2a of the carbonization furnace 2. An oxygen-containing gas is blown from a high temperature tuyere 21 into the remaining coolant gas not drawn from the carbonization furnace 2, and the remaining coolant gas is converted into high temperature carbonization gas by burning the oxygen-containing gas in the carbonization furnace 2. As a result, the conventional need to generate high temperature carbonization gas and feed it into the carbonization furnace 2 is eliminated, and the use of a heating device for high temperature carbonization gas becomes unnecessary.

Description

  The present invention relates to a method and an apparatus for producing molded coke in which coal is continuously carbonized in a carbonization furnace.

  As a conventional method for producing molded coke, for example, the one described in Patent Document 1 is known. FIG. 4 shows a schematic view of a conventional apparatus for producing molded coke. In FIG. 4, 1 is a coal forming facility, 2 is a carbonization furnace, 3 is a discharge device, 4 is a sensible heat recovery device, 5 is a gas cooling device, 6 is a gas blower, 7 is a dust collector, 8 is a cooling gas pipe, 9 is a low temperature carbonization gas pipe, 10 is a gas blower, 11 is a low temperature carbonization gas heater, 12 is an ejector, 30 is a high temperature carbonization gas pipe, 31 is a gas blower, and 32 is a high temperature carbonization gas heater.

  As shown in FIG. 4, in a conventional molded coke manufacturing facility, a part of the top gas of the dry distillation furnace 2 is introduced as a cooling gas into the lower part of the cooling zone 2c at the lower part of the dry distillation furnace 2, and the gas that has passed through the cooling zone 2c. Is extracted from the upper part of the cooling zone 2c by the ejector 12 using the gas preheated by the heater 11 as the driving source and supplied to the low temperature tuyere 20 of the dry distillation furnace 2 as a low temperature dry distillation gas. Further, a part of the top gas of the dry distillation furnace 2 is heated by the high temperature dry distillation gas heater 32 and supplied to the high temperature tuyere 21 of the dry distillation furnace 2 as high temperature dry distillation gas.

  In Patent Document 2, a part of the top gas of the dry distillation furnace is introduced into the lower part of the cooling zone, and the gas that has passed through the cooling zone is heated by a high-temperature gas heater without being extracted from the upper part of the cooling zone. A method is disclosed in which a carbonization gas is blown into a high temperature carbonization zone and mixed with a cooling gas.

Japanese Examined Patent Publication No. 56-47234 JP 2010-202838 A

  However, each of the above conventional methods requires a heating device for high temperature dry distillation gas, and in order to heat to a temperature of 850 to 950 ° C. required for high temperature dry distillation, a metal heat exchanger is heat resistant. In the past, two regenerative hot stoves were used by switching alternately. For this reason, the facilities become large-scale, which is a cause of high costs. In addition, since the two hot stoves are operated by switching alternately every about 30 minutes, there is a state where the high-temperature dry distillation gas does not flow temporarily, and uneven dry distillation occurs. Furthermore, when heat exchange between the gas and the heat storage bricks of the hot stove furnace, the heavy components in the gas are decomposed and carbon soot is generated, so that the ducts and tuyere are blocked. .

On the other hand, in the conventional latter method, in order to cool the molded coke at about 900 ° C. to 100 ° C. or less, a cooling gas amount of about 900 Nm ³ / t-bri per ton of coal is required due to heat exchange characteristics. is necessary. In addition, in order to obtain a gas having a temperature of 850 to 950 ° C. necessary for high temperature carbonization, it is necessary to mix a higher temperature high temperature carbonization gas of 1000 ° C. or higher. The amount of gas flows in, the heating rate of the coal is increased, and the heat shrinkage stress in the process of coking increases, and cracking of the molded coke tends to occur. As a result, there is a problem that the yield of the molded coke product is lowered.

  Therefore, in the present invention, a heating device for high temperature carbonization gas is not required, and high temperature carbonization gas is supplied stably and continuously to suppress cracking of molded coke, thereby preventing a decrease in the yield of molded coke products. It is an object of the present invention to provide a method and apparatus for producing a possible molded coke.

  The method for producing molded coke according to the present invention is a method for producing molded coke in which carbonized coal is continuously carbonized in a carbonization furnace having a low temperature carbonization zone and a high temperature carbonization zone in the upper part and a cooling zone in the lower part. Extracting a part of the cooling gas introduced into the cooling zone, supplying it as a low temperature dry distillation gas to the low temperature distillation zone of the dry distillation furnace, blowing oxygen-containing gas into the remaining cooling gas not extracted from the dry distillation furnace, It includes burning in a carbonization furnace to form a high temperature carbonization gas. The oxygen-containing gas is oxygen or air.

  The apparatus for producing coke of the present invention is an apparatus for producing coke coke which continuously carbonizes coal in a carbonization furnace having a low temperature carbonization zone and a high temperature carbonization zone in the upper part and a cooling zone in the lower part. A part of the cooling gas introduced into the cooling zone is extracted and supplied as a low-temperature carbonization gas to the low-temperature carbonization zone of the carbonization furnace, and the remaining cooling gas not extracted from the carbonization furnace in the carbonization furnace. And an oxygen-containing gas supply pipe that blows an oxygen-containing gas for burning into a high-temperature carbonization zone of a carbonization furnace.

  In these inventions, only a part of the cooling gas is extracted from the carbonization furnace, and the oxygen-containing gas is blown into the cooling gas remaining in the carbonization furnace, thereby burning the cooling gas in the carbonization furnace to obtain a high-temperature carbonization gas. Therefore, it is not necessary to generate and supply high-temperature dry distillation gas into the dry distillation furnace as in the prior art, and a high-temperature dry distillation gas heating device is not required. Moreover, since a part of the cooling gas is extracted from the carbonization furnace, it is possible to prevent an excessive amount of gas from flowing into the high temperature carbonization zone of the coal.

(1) A part of the cooling gas introduced into the cooling zone of the carbonization furnace is extracted, supplied to the low temperature carbonization zone of the carbonization furnace as a low temperature carbonization gas, and oxygen with respect to the remaining cooling gas not extracted from the carbonization furnace By blowing the contained gas and combusting it in the carbonization furnace, it is not necessary to generate the high temperature carbonization gas and supply it to the carbonization furnace as in the past, and there is no need for a high temperature carbonization gas heating device. Become.

(2) Since a part of the cooling gas is extracted from the carbonization furnace, it is possible to prevent an excessive amount of gas from flowing into the high temperature carbonization zone of the coal, and to adjust the amount of the high temperature carbonization gas appropriately. Can be heated at an appropriate temperature increase rate, so that cracking of the molded coke can be suppressed and a decrease in the yield of the molded coke product can be prevented.

It is the schematic of the shaping | molding coke manufacturing apparatus in embodiment of this invention. It is a figure which shows the Example of each gas supply amount of the shaping | molding coke manufacturing apparatus of FIG. It is a figure which shows each gas supply amount of the conventional shaping | molding coke apparatus as a comparative example. It is the schematic of the conventional shaping | molding coke manufacturing apparatus.

  FIG. 1 is a schematic view of a molded coke manufacturing apparatus according to an embodiment of the present invention. In FIG. 1, a molded coke manufacturing apparatus according to an embodiment of the present invention includes a molded coal manufacturing facility 1, a carbonization furnace 2, a discharge device 3, a sensible heat recovery device 4, a gas cooling device 5, and a gas blower 6. , Dust collector 7, cooling gas pipe 8, low-temperature dry distillation gas pipe 9, gas blower 10, low-temperature dry distillation gas heater 11, ejector 12, oxygen-containing gas pipe 13, gas blower 14, and oxygen-containing gas And a preheater 15.

  The charcoal manufacturing facility 1 is a facility in which a binder is added to the raw coal powder and the charcoal is manufactured by a molding machine. The carbonization furnace 2 is a vertical type carbonization furnace that continuously carbonizes coal supplied from the top. The carbonization zone 2a in which the upper part is carbonized in order from the top at a low temperature of about 650 ° C., and carbonization at a high temperature of about 900 ° C. A high temperature carbonization zone 2b is formed, and a lower portion is a cooling zone 2c cooled by a cooling gas of 50 to 60 ° C. A low temperature tuyere 20 for introducing a low temperature dry distillation gas is provided below the low temperature carbonization zone 2a, and a high temperature tuyere 21 for introducing an oxygen-containing gas is provided below the high temperature dry distillation zone 2b. In addition, a cooling gas discharge port 22 and an introduction port 23 are provided in the upper and lower portions of the cooling zone 2c, respectively. A furnace top gas discharge port 24 is provided at the top of the dry distillation furnace 2.

  The coal coal input from the upper part of the carbonization furnace 2 descends the carbonization furnace 2, and is carbonized by being given a desired heating rate pattern in the low temperature carbonization zone 2a and the high temperature carbonization zone 2b in the process. The high-temperature coke that has passed through the low-temperature carbonization zone 2a and the high-temperature carbonization zone 2b is cooled to a temperature that can be handled in the process of descending the cooling zone 2c, and is discharged out of the furnace from the discharge device 3 as molded coke.

  The sensible heat recovery device 4 is a device that recovers sensible heat from the furnace top gas that has passed through the carbonization furnace 2. The sensible heat of the furnace top gas that has passed through the carbonization furnace 2 is recovered by the sensible heat recovery device 4, cooled by the gas cooling device 5, and pumped to the dust collector 7 by the gas blower 6. Most of the gas that has passed through the dust collector 7 is sent as a circulating gas to the cooling gas pipe 8 and the low-temperature dry distillation gas pipe 9, and the rest is sent as a recovered gas to the byproduct recovery apparatus.

  The cooling gas pipe 8 is connected to the cooling gas inlet 23 at the lower part of the cooling zone 2c, and the circulating gas is supplied from the inlet 23 to the cooling zone 2c through the cooling gas pipe 8 as a cooling gas. The low temperature carbonization gas pipe 9 is connected to a low temperature tuyere 20 at the lower part of the low temperature carbonization zone 2a, and the circulating gas is pumped to the low temperature carbonization gas heater 11 by the gas blower 10, heated to a predetermined temperature, and passed through the ejector 12. It is supplied from the low temperature tuyere 20 to the low temperature carbonization zone 2a as a low temperature carbonization gas.

  At this time, a part of the cooling gas that has passed through the cooling zone 2c is extracted from the extraction pipe 16 connected to the cooling gas discharge port 22, mixed with the low temperature dry distillation gas by the ejector 12, and supplied to the low temperature dry distillation zone 2a. Is done. The cooling gas that has not been withdrawn from the carbonization furnace 2 is partially burned by the oxygen-containing gas blown from the high-temperature tuyere 21 at the lower part of the high-temperature carbonization zone 2b through the oxygen-containing gas pipe 13 to form high-temperature carbonization gas. Used for high temperature carbonization in zone 2b. An oxygen-containing gas preheater 15 is provided in the middle of the oxygen-containing gas pipe 13, and the oxygen-containing gas pumped by the gas blower 14 is preheated to a predetermined temperature of 600 to 700 ° C.

  In the molded coke manufacturing apparatus having the above-described configuration, only a part of the cooling gas is extracted from the dry distillation furnace 2, and oxygen-containing gas is blown into the cooling gas remaining in the dry distillation furnace 2 to burn the cooling gas in the dry distillation furnace 2. Therefore, it is not necessary to generate a high temperature dry distillation gas and supply it to the dry distillation furnace 2 as in the prior art, and a high temperature dry distillation gas heating device is not required. Further, since the amount of the cooling gas extracted is smaller than that of the conventional method, the scattering of the coke powder to the discharge port 22 can be reduced, so that the blockage by the coke powder and the wear of the nozzle portion of the ejector 12 are reduced.

  Further, since a part of the cooling gas is extracted from the carbonization furnace 2, it is possible to prevent an excessive amount of gas from flowing into the high temperature carbonization zone 2b of the coal, and to adjust the amount of the high temperature carbonization gas appropriately. Can be heated at an appropriate rate of temperature rise, so that cracking of the molded coke can be suppressed and a decrease in the yield of the molded coke product can be prevented. Moreover, since the soot at the time of heat exchange with a heating apparatus does not generate | occur | produce like the conventional molded coke manufacturing apparatus, the obstruction | occlusion by the soot in the oxygen containing gas piping 13 or the high temperature tuyere 21 can be prevented.

  FIG. 2 is a diagram showing an example of each gas supply amount of the molded coke manufacturing apparatus of FIG. 1, and FIG. 3 is a diagram showing each gas supply amount of the conventional molded coke manufacturing apparatus described in Patent Document 1 as a comparative example. .

In the embodiment shown in FIG. 2, a flow meter 25a and a flow rate adjustment valve 25b are provided in the middle of the cooling gas pipe 8 connected to the inlet 23 of the cooling zone 2c, and these flow meter 25a and flow rate adjustment valve 25b. Thus, the supply amount of the cooling gas to the inlet 23 of the cooling zone 2c is adjusted to be 909 Nm ³ / t-bri per ton of coal. Further, a flow meter 26a and a flow rate adjustment valve 26b are provided in the middle of the low temperature dry distillation gas pipe 9, and the supply amount of the low temperature dry distillation gas sent from the low temperature dry distillation gas heater 11 by these flow meter 26a and flow rate adjustment valve 26b. Is adjusted to be 1,570 Nm ³ / t-bri.

The low temperature dry distillation gas pipe 9 is branched into a pipe 9 a connected to the ejector 12 and a pipe 9 b that bypasses the ejector 12. In the middle of the pipe 9a connected to the ejector 12, a flow rate adjusting valve 27b is provided. A flow meter 27a is provided in the middle of the extraction pipe 16 for extracting the cooling gas from the discharge port 22 of the cooling zone 2c. By this flow meter 27a, the amount of low-temperature dry distillation gas (ejector drive gas) supplied to the ejector 12 by the flow rate adjustment valve 27b so that the cooling gas amount extracted from the discharge port 22 of the cooling zone 2c becomes 612 Nm ³ / t-bri. Amount) is adjusted. As a result, the amount of low-temperature dry distillation gas supplied to the low-temperature tuyere 20 at the lower part of the low-temperature carbonization zone 2a is a total of 2,182 Nm ³ / t-bri of gas supplied through the pipes 9a and 9b and the extraction pipe 16. .

In the upper part of the cooling zone 2c, an amount obtained by subtracting the amount of the cooling gas extracted from the discharge port 22 from the supply amount of the cooling gas blown from the inlet 23 at the lower part of the cooling zone 2c (297 Nm ³ / t− bri) remains and flows to the upper hot distillation zone 2b. A thermometer 28a is provided in the furnace below the high-temperature carbonization zone 2b, and the oxygen-containing gas is flown from the oxygen-containing gas pipe 13 at a flow rate adjustment valve 28b so that the temperature becomes 900 ° C. . Under the above conditions, the oxygen-containing gas amount is 80 Nm ³ / t-bri.

On the other hand, in the comparative example shown in FIG. 3, all the cooling gas of 909 Nm ³ / t-bri blown from the inlet 23 at the lower part of the cooling zone 2 c is extracted by the ejector 12 and supplied from the low temperature dry distillation gas pipe 9. 1, 273 Nm ³ / t-bri of low temperature dry distillation gas, and supplied to the low temperature dry distillation zone 2a. Therefore, in order to dry distillation under the same conditions as in the embodiment shown in FIG. 2, it is necessary to supply a high temperature dry distillation gas of 378 Nm ³ / t-bri to the high temperature dry distillation zone 2b.

The high-temperature carbonization gas supplied to the high-temperature carbonization zone 2b needs to be heated to 900 ° C. by a heating device. As described above, the heating device becomes large, but in the examples, as described above. Since the non-corrosive oxygen-containing gas preheated to 600 to 700 ° C. is only supplied in a small amount of 80 Nm ³ / t-bri, the oxygen-containing gas preheater 15 can be small in size and is a metal heat exchanger. Therefore, the cost can be significantly reduced as compared with the conventional hot stove. In addition, in order to supply a high-temperature dry distillation gas at 900 ° C. in the comparative example, the high-temperature dry distillation gas pipe 30 needs to be protected with an expensive refractory, but in the examples, since it is 600 to 700 ° C., There may be little heat insulating material for preventing the heat dissipation.

  INDUSTRIAL APPLICABILITY The present invention is useful as a manufacturing method and a manufacturing method of molded coke that continuously forms carbonized coal to obtain molded coke.

DESCRIPTION OF SYMBOLS 1 Coal-coal production equipment 2 Carbonization furnace 2a Low temperature carbonization zone 2b High temperature carbonization zone 2c Cooling zone 3 Discharge device 4 Sensible heat recovery device 5 Gas cooling device 6, 10, 14 Gas blower 7 Dust collector 8 Cooling gas piping 9 Low temperature carbonization gas piping DESCRIPTION OF SYMBOLS 11 Low temperature dry distillation gas heater 12 Ejector 13 Oxygen containing gas piping 15 Oxygen containing gas preheater 16 Extraction piping 20 Low temperature tuyere 21 High temperature tuyere 22, 24 Outlet 23 Inlet 25a, 26a, 27a Flowmeter 25b, 26b, 27b , 28b Flow control valve 28a Thermometer

Claims (2)

A method for producing molded coke in which carbonized coal is continuously carbonized in a carbonization furnace having a low temperature carbonization zone and a high temperature carbonization zone at the top and a cooling zone at the bottom,
Extracting a part of the cooling gas introduced into the cooling zone of the carbonization furnace and supplying it to the low temperature carbonization zone of the carbonization furnace as a low temperature carbonization gas;
A method for producing molded coke, comprising blowing an oxygen-containing gas into the remaining cooling gas that has not been withdrawn from the carbonization furnace and combusting in the carbonization furnace to obtain a high temperature carbonization gas. A molding coke manufacturing apparatus for continuously carbonizing coal in a carbonization furnace having a low temperature carbonization zone and a high temperature carbonization zone at the top and a cooling zone at the bottom,
A low temperature dry distillation gas pipe for extracting a part of the cooling gas introduced into the cooling zone of the dry distillation furnace and supplying the low temperature dry distillation gas to the low temperature dry distillation zone of the dry distillation furnace;
An oxygen-containing gas supply pipe for blowing an oxygen-containing gas for burning the remaining cooling gas not extracted from the carbonization furnace in the carbonization furnace into a high-temperature carbonization zone of the carbonization furnace. Molded coke manufacturing equipment.

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