JPH03296597A - Coke production equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a coke production facility mainly comprising a vertical coke oven for producing coke by carbonizing coal.

(Prior Art) Coke production equipment currently in general use is mainly a type of oven called a horizontal coke oven.

In a horizontal coke oven, coal is charged from the top of the oven, and coke is discharged horizontally using an extruder.
Although it has a long history and a lot of operational knowledge, due to its structure,
In order to discharge coke, it is necessary to equip the coke oven with full-height doors (called oven lids) on both sides, which prevents gas leakage from the oven lid during carbonization and the generation of soot and dust when discharging coke. It is unavoidable and has the undesirable problem of environmental pollution. Furthermore, as additional equipment, mobile machinery such as coal loading cars, extruders, guide cars, and fire engines are required.
It is necessary to pay for the equipment and secure operating personnel, and the working environment is not necessarily good.

Recently, when updating coke oven equipment, attempts have been made to increase productivity and reduce pollution sources by increasing the size of coke ovens in order to alleviate the problems of horizontal coke ovens mentioned above. As mobile machinery becomes larger as a result of this trend, it does not necessarily lead to a reduction in equipment costs, and the working environment is not sufficiently improved, making it difficult to make fundamental technical improvements to horizontal coke ovens due to their structure. I have to say.

Here, the issues with horizontal coke ovens can be summarized as follows.

■ Mobile machinery is essential as ancillary equipment, which is disadvantageous in terms of equipment costs and labor savings.

■ Carbonization efficiency, that is, heating efficiency, is poor, making it impossible to reduce the installed capacity of the furnace.

■ Generation of soot and dust from the furnace opening worsens the working environment.
There is a risk of causing pollution.

■ Difficult to shut down the furnace, resulting in poor production flexibility.

Historically, in addition to horizontal coke ovens, some vertical coke ovens have also been put into practical use in Europe, and are also used in some parts of Japan. However, most of them either disappeared without being enlarged or are only operating in small quantities.

Vertical coke ovens, in which coal is charged from the top of the oven and coke is discharged from the bottom of the oven using its own weight, appear to have been operated without any problems, with almost no moving machinery used.

For example, "Recent Animal Charcoal Production Method and By-Product Treatment Method" by Taizo Kuroda, Maruzen Co., Ltd. (July 1912) describes an Elliott-John furnace with a rectangular horizontal cross section and an arm with a circular horizontal cross section. Strong-type furnaces are introduced. The former uses 14 horizontal flues for heating in the furnace height direction, which tends to cause temperature distribution in the horizontal direction, and gas distribution is complicated, making operation difficult as the number of furnaces increases. It is inferred. In addition, the latter has a cylindrical furnace body and heats from the outer periphery of the furnace in the direction of the height of the furnace using vertical flutes, but as the number of furnaces increases, the number of furnaces must be consolidated, so the equipment area increases. It is expected that the gas distribution will increase proportionally and the gas distribution will become more complex. However, since no moving machinery was required and there were fewer entrances to the furnace, it is presumed to be effective in suppressing soot and dust.

On the other hand, various molded coke processes have been studied, which are characterized by unmanned, continuous, and non-polluting operations, but have not yet been put to practical use.

In the molded coke method, powdered coal is agglomerated into pea charcoal, and this agglomerate is made into coke by direct gas heating, but the odor emitted from the tar and pitch-based binders used during molding It is not environmentally friendly, and there are restrictions on the type of coal that can be used in the molded coke process. Furthermore, since the heated gas used for carbonization is mixed with the gas generated during carbonization, the amount of gas inevitably increases, and the gas processing equipment needs to be increased several times the scale of the horizontal coke oven equipment.

Therefore, it is unlikely that a significant reduction in equipment costs can be expected.

For the above reasons, partial improvements in the conventional technology are not sufficient to solve the problems with the currently commonly used horizontal coke ovens and, by extension, the problems with coke production equipment using this oven, and new coke Creation of manufacturing technology is strongly desired.

(Problems to be Solved by the Invention) This invention is based on a vertical coke oven that eliminates the drawbacks of the horizontal coke oven as described above, reducing equipment costs, improving carbonization efficiency, and improving the working environment. In addition, it is an object of the present invention to provide coke production equipment that can particularly improve thermoeconomic efficiency.

(Means for Solving the Problems) The gist of the present invention lies in the following coke production equipment (1) and (2).

■ A coke oven that produces coke by carbonizing powdered coal, with a carbonization chamber having a rectangular horizontal cross section, a coal charging port at the top and a coke discharge port at the bottom. A vertical flue is installed on two opposite sides of the carbonization chamber with a brick wall in between, and an air passage is installed outside the vertical flue with a brick wall in between. 1. A coke production facility characterized by being equipped with a reheating device that heats the coke directly by gas heating, and a cooling device that dry-cools the coke discharged from the reheating device.

(2) The vertical coke oven described in (1) above is provided with a reheating device that heats the coke discharged from the vertical coke oven by direct gas heating, and a cooling device that dry-cools the coke discharged from the reheating device, Further, a drying/preheating machine for drying and preheating powdered coal using high-temperature combustion exhaust gas discharged from the vertical coke oven, and charging the dried and preheated powdered coal into the vertical coke oven. Coke manufacturing equipment characterized by being equipped with an air flow conveying device.

Figures 1 and 2 are diagrams showing the configuration of an example of a vertical coke oven (one unit), with Figure 1 being a longitudinal sectional view and Figure 2 being A-A.
FIG. 3 is an enlarged horizontal cross-sectional view. In FIGS. 1 and 2, l is a carbonization chamber with a rectangular horizontal cross section, 2 is a coal charging port provided at the top of the carbonization chamber 1, and 3 is a coke discharge port provided at the bottom of the carbonization chamber 1. , 4 is an outlet for the generated gas (carbonized gas) generated in the carbonization chamber, 5 is a vertical flue (heating flame path) provided on two opposing sides of the carbonization chamber with a brick wall in between,
6 is a fuel gas inlet for feeding fuel gas into the vertical flue 5; 7 and 8 are air passages provided outside the vertical flue with a brick wall in between; 9 is an air inlet for feeding air into the air passage 7; 10 is a combustion gas discharge port for discharging the combustion exhaust gas stored in a vertical flue; 11 is a coke chute provided below the coke discharge port 3; 12 is a heating wall; 13
14 is the side wall of the coking chamber, 14 is the partition wall, and 15 is the outer wall. By installing a large number of furnaces configured in this way adjacent to each other on both sides as shown by the broken line in FIG. 2, the required coke production amount can be met. It is possible to have the ability to

FIG. 3 is a diagram showing an example of the configuration of the coke manufacturing equipment of the present invention, in which the vertical coke oven shown in FIGS. 1 and 2 is provided with a reheating device and a dry cooling device. In the figure, 16 is a vertical coke oven, 35 is a reheating device for coke discharged from the vertical coke oven 16, and 36 is a cooling device for dry cooling the coke discharged from the reheating device.

FIG. 4 shows that in the coke manufacturing apparatus shown in FIG. 3, the coal to be charged into the vertical coke oven is further dried and
FIG. 2 is a diagram showing an example of the configuration of a coke manufacturing facility equipped with a drying/preheating machine for preheating and an air flow conveying device. In the same figure,
17 is a drying/preheating machine that dries or preheats powdered coal (wet coal); 18 is a heat exchanger; 19 is a collector that collects coal in the exhaust gas discharged from the drying/preheating machine 17; 20 is a dust collector that collects powdered coal remaining in the exhaust gas discharged from the collector 19, which collects dried/preheated coal 25 collected by the collector 19 and recovered coal 2 collected by the dust collector 20.
An air flow conveying facility 21 is provided for charging coal 7 into the vertical coke oven 16 as charging coal 29. In this example, the collector 19, the dust collector 20, the blower B1, the blower B2, and the piping connecting them (the part surrounded by the dashed line in the figure) are collectively referred to as an air flow conveying device 21.

(Operation) In the vertical coke oven shown in FIGS. 1 and 2, coal is charged into the coking chamber 1 from the coal charging port 2 at the top of the oven. Heating is performed via a heating wall 12 from a vertical flue 5 arranged outside the carbonization chamber l. The material for the heating wall 12 is preferably silica brick or chamotte brick. The fuel gas is introduced from the bottom of the vertical flue 5, and the air is introduced from the bottom of the air passage 7 located outside the vertical flue 5, and then turns around at the top of the furnace and passes through the air passage 8 downward. It is preheated and introduced into the bottom of the vertical flue 5. Here, air and fuel gas are mixed and subjected to combustion. The carbonized coke is discharged under its own weight by opening the furnace cover of the coke discharge port 3 provided at the bottom of the carbonization chamber 1 as shown by the broken line in the figure. Gas generated during carbonization is discharged from the generated gas outlet 4 and recovered.

In this vertical coke oven, the raw material coal is charged from the top, and the coke after carbonization is discharged by its own weight by opening the oven lid at the bottom of the oven. Does not require heavy machinery such as cars.

Heat transfer for carbonizing coal is carried out not only from the heating surface with the vertical flute 5 (heating wall 12 in Figure 2), but also from the other two surfaces that receive heat from the vertical flute 5 (the carbonization wall in Figure 2). Since the heat transfer is also carried out from the chamber side wall 13), the heat transfer efficiency is greatly improved. Regarding the cross-sectional shape of the carbonization chamber l, it is desirable that the length L of the heating wall 12 does not exceed the length of the side wall 13 of the carbonization chamber in order to improve heat transfer efficiency.

The air introduced from the outside is preheated by the heat dissipated from the vertical flue 5 to the outer wall of the furnace (outer wall 15 in Fig. 2) when passing through the air passage 7.8, so that combustion is carried out smoothly. , a high temperature combustion state is obtained.

The soot and dust generated from coke ovens is only generated when the lid at the bottom of the oven is opened, which can be significantly reduced compared to horizontal coke ovens, which is also advantageous in terms of improving the working environment and preventing dust pollution. .

Furthermore, in the operation of this coke oven, each unit uses an independent carbonization method, so it is easy to respond to fluctuations in coke production, and in extreme cases, even if part of the oven is stopped, it will not affect other ovens. The impact will be small and production elasticity will be significantly improved.

In the coke production equipment of the present invention shown in FIG. The coke 34 is heated to 800°C in the reheating device 35.
It will be reheated further. Reheated coke 38 is cooled by cooling device 3
At step 6, the coke is cooled by a cooling gas 39 (dry extinguishing), and after cooling is discharged from the cooling device 36 as coke 40. If crude gas (low temperature) after removing oil such as tar from the carbonized gas 33 generated from the vertical coke oven 16 or blast furnace gas generated at a steelworks is used as the cooling gas 39, the cooling can be achieved. Part of the high-temperature gas left behind can be partially combusted and effectively used for reheating coke. That is, a part of the cooled gas 41 after cooling the reheated coke 38 is introduced into the reheating device 35, mixed with air 42 and partially combusted, and the carbonized coke 34 can be directly heated. The reheated gas 43 generated in this reheating device 35 not only has a high temperature but also generates flammable pyrolysis gas containing hydrogen as a main component when reheating coke with a low carbonization temperature. It can be effectively used as a fuel gas in the coke oven 16 without preheating.

In the vertical coke oven 16, the central part of the carbonization chamber is at least 50
The coke 34 after carbonization is carbonized to 0°C and then reheated to 800°C or higher in the reheating device 35 at a temperature of at least 500°C in which the coal completes melting and solidification during the process from coal to coke. Although the external heating method with a slow carbonization rate is preferable until the coke quality W (coke strength) f! This is because heating by external heating to the high carbonization temperature of 800°C or higher required for preservation is poor in productivity. That is, coke productivity is improved by lowering the carbonization temperature of the vertical coke oven 16, and coke quality is ensured by reheating the resulting coke that has not been carbonized sufficiently. Note that the vertical coke oven, which has a rectangular horizontal cross section, not only heats externally from the vertical friers provided on two opposing sides through the brick walls, but also heats the other two sides.
The carbonization efficiency is high due in part to the heat transfer effect from the side walls of the surface, and in combination with the above-mentioned reduction in the carbonization temperature, this is effective for increasing the productivity of the coke oven.

Below, we give the operating specifications (conditions) when coal is carbonized, reheated, and cooled using equipment with the configuration shown in Figure 3, and calculate the heat balance and material balance. This paper describes the results of comparisons with typical operating values, heat balance, and material balance in a coke manufacturing facility with dry fire extinguishing equipment.

The assumptions for the calculation are as follows.

The reheating device and cooling device are the 51st! It has a directly connected structure as shown in 1. The cooling gas 39 blown into the cooling section 44 has a calorific value of 11401 cal/N.
A part of the high temperature gas after cooling the reheated coke for 3 days is introduced into the reheating section 45 using M gas of
The coke 34 was partially combusted and used for reheating the coke 34.

Furthermore, the high-temperature gas 43 after reheating was used as fuel for the vertical coke oven. In addition, the furnace temperature is 1150°
It was set as C. In addition, the charging coal has a moisture content of 8% as shown in Table 1.
．． 7% coal was used.

Regarding the rolling conditions in Table 1 and Table 4, first, the coke 34 is discharged in the coke oven when the temperature in the coal (temperature at the center of the coking chamber) reaches 500°C, and then this coke 34 is The coke 38 was reheated to 850° C. by direct gas heating using the reheating/cooling device shown in FIG. 5, and the reheated coke 38 was cooled to 180° C. in the cooling section 44.

The trial calculation results are shown in Table 4.

(Hereinafter, blank space) As is clear from the table, when using the equipment of the present invention, the amount of gas generated in the coke oven is lower than in the case of conventional equipment because the carbonization temperature is low, but the amount of heat required for carbonization is 100 M
It was about cal/L less. In addition, even though the coke discharged from the coke oven has a temperature in the coal as low as 500°C, the average temperature is 735°C, and it was determined that there was no problem as it had sufficient strength to withstand transportation.

The heating conditions for the coke 34 in the reheating section 45 are 850″C.
However, during this heating, combustible gas containing hydrogen as a main component (gas 43 after reheating) exceeds the amount of heat required for reheating.
) 7ONm''/l was obtained, and the gas temperature was also high, so it was judged that it could be used as part of the fuel gas for a coke oven.

Furthermore, in the cooling section 44, the amount of heat recovered is small compared to conventional equipment (dry type fire extinguishing equipment), but this is because the coke temperature introduced into the cooling section 44 is low, and some of the high temperature gas after cooling is This is because the amount of heat is sent to the coke reheating section 45 and is not included in the amount of recovered heat.

Comprehensively evaluated, the amount of heat required for carbonization minus the amount of recovered heat is higher than in the case of conventional equipment, but the sensible heat of the combustion exhaust gas discharged from the coke oven is large; Considering that the coke production equipment of the present invention can be effectively used as a heat source for boilers or for coal drying, it can be said that the coke manufacturing equipment of the present invention is extremely advantageous from the viewpoint of thermoeconomic efficiency.

Regarding the quality of coke, at least 800°
If it is reheated to C, there is no particular problem as coke for blast furnaces, and this temperature can be easily adjusted as necessary by adjusting the discharge temperature in the vertical coke oven or the heating temperature in the reheating device. It is something that can be done.

(Effects of the Invention) The coke production equipment of the present invention, which is mainly a vertical coke oven, is superior to the horizontal coke oven in various aspects such as reducing equipment costs, improving carbonization efficiency, improving the working environment, and improving thermoeconomic efficiency. It is superior to conventional coke production equipment, which is mainly based on coke production, and can be said to greatly contribute to the development of coke production technology in the future.

[Brief explanation of the drawing]

1 and 2 are diagrams showing the configuration of an example of a vertical coke oven used in the coke production equipment of the present invention, in which FIG. 1 is a longitudinal cross-sectional view, and FIG. It is an enlarged sectional view. FIG. 3 and FIG. 4 are diagrams showing the configuration of an example of coke production equipment of the present invention. Figure 5 shows the reheating and
It is a figure showing the composition of an example of a cooling device.

Claims (2)

[Claims] (1) A coke oven that produces coke by carbonizing powdered coal, with a carbonization chamber whose horizontal cross section is rectangular, with a coal charging port at the top and a coke discharge port at the bottom. In a vertical coke oven, a vertical flue is installed on two opposing sides of the carbonization chamber with a brick wall in between, and an air passage is installed outside the vertical flue with a brick wall in between.
A coke production facility characterized by being equipped with a reheating device that heats the coke discharged from the vertical coke oven by direct gas heating, and a cooling device that dry-cools the coke discharged from the reheating device. (2) The vertical coke oven according to claim (1) includes a reheating device that directly heats the coke discharged from the vertical coke oven by gas heating, and a dry cooling method for dry cooling the coke discharged from the reheating device. A cooling device is provided, and a drying/preheating machine for drying and preheating powdered coal using high-temperature combustion exhaust gas discharged from the vertical coke oven, and a drying/preheating machine for drying and preheating the powdered coal using the high temperature combustion exhaust gas discharged from the vertical coke oven, and a drying/preheating machine for drying and preheating the powdered coal to the vertical coke oven Coke manufacturing equipment characterized by being equipped with an air flow conveying device for charging into a furnace.