KR100543185B1 - A regenerative burner heating system for improving buring efficncy - Google Patents

Abstract

The present invention provides a furnace inlet through which a slab is introduced, a charging zone heated by passing the slab sequentially after passing through the furnace inlet, a preheating zone for preheating the slab, and the slab passing through the preheating zone. The slab comprises a heating table for heating to a target temperature, a cracking table for homogenizing the slab passing through the heating table, and a partition for preventing the inflow of external air at the moment the slab is introduced between the charging table and the preheating table. In a regenerative burner heating system for producing a coil after heating to a temperature, by installing a plurality of partitions spaced apart at regular intervals at the lower entrance of the furnace in which the slab is moved and the charging zone where the slab is heated. A regenerative burner heating system that prevents the inflow of external air by opening the slab as the slab is introduced. Shall be.

Regenerative Burner

Description

Regenerative burner heating system for improving buring efficncy

1a shows a heating system of a regenerative ceramic burner.

1B is a view showing a combustion state of a regenerative ceramic burner.

Figure 2a is a front view showing the overall structure of the conventional heating furnace.

Figure 2b is a plan view showing the overall structure of the conventional heating furnace.

Figure 2c is a side view showing a conventional charging station installation structure.

  3 is a view showing a conventional charging stand structure.

4 is a view showing the entire furnace structure according to the present invention.

5 is a plan view showing the entire furnace structure according to the present invention.

Figure 6 is a side view showing a charging stand facility structure according to the present invention.

7 is a view showing a charging structure according to the present invention.

Figure 8a is a photograph showing the installation of the partition according to the present invention.

Figure 8b is a photograph showing the installation of the partition according to the present invention.

9 is a view showing the installation specifications of the partition wall designed in six blocks according to the present invention.

10 is a view showing a position of measuring the change in the ambient temperature of the heat storage burner.

11 is a view showing a temperature change according to the conventional entrance door opening and closing.

12A is a diagram showing a change in atmosphere temperature when there is no footage.

12B is a diagram showing a change in atmosphere temperature when there is a footage.

13A is a view showing a measurement position of an ambient temperature and an oxygen concentration change amount.

13B is a view showing a measurement position of an ambient temperature and an oxygen concentration change amount.

13C is a view comparing atmospheric temperature changes of a conventional heating furnace and a converted heating furnace.

13d is a view comparing oxygen concentration changes of a conventional heating furnace and a converted heating furnace.

<Description of the symbols for the main parts of the drawings>

1: burner body 2: ball type heat accumulator

3: fuel switching device 4: exhaust gas switching device

5: air changer 6: A-burner

7: D-burner 8: B-burner

9: C-Burner 15: Partition

16: entry path 17,18: partition

19,20,21,22: Atmosphere temperature 25: Temperature measuring points 3,4

26: temperature measurement point 1,2 27: oxygen measurement point 3,4

28: oxygen measuring point 1,2 31: oxygen concentration in conventional heating furnace

32: oxygen concentration of the present invention furnace

The present invention relates to a regenerative burner heating system for improving combustion efficiency. In particular, in order to improve the combustion efficiency of a regenerative burner heating system, a partition for suppressing the intrusion of external air is installed in the lower part of the charging zone, which is a combustion section at the entrance of the heating furnace. The present invention relates to a regenerative burner for improving combustion efficiency which prevents an unstable combustion demand of a regenerative burner while preventing an atmosphere temperature decrease and an increase in oxygen concentration.

Figure 1a is a view showing a heating system of the regenerative ceramic burner, Figure 1b is a view showing the combustion state of the regenerative ceramic burner, Figure 2a is a front view showing the overall structure of the conventional heating furnace, Figure 2b is a conventional heating furnace It is a top view which shows the whole installation structure, FIG. 2C is a side view which shows the conventional charging stand installation structure, FIG. 3 is a figure which shows the conventional charging stand structure.

In general, a heating furnace, which is a leading process of a hot rolling mill, is a process of heating slab to a target temperature required to make a final product coil. Conventional equipment structure of the furnace consists of furnace inlet 10, charging stand 11, preheating stand 12, the heating stand 13, the cracking stand 14, in particular, the atmosphere temperature at the entrance of the furnace to a high temperature Two pairs of regenerative burners are in operation at the top and the bottom of the charging station to manage and increase the production capacity of the furnace.

The regenerative heating system is composed of a burner body (1), a ball type heat storage (2), a fuel switching device (3), an exhaust gas switching device (4), and an air switching device (5). At intervals, the combustion and exhaust treatments alternate.

The regenerative burner control method first operates the A-burner 6 and the C-burner 9 and exhausts the combustion gas generated at this time to the B-burner 8 and the D-burner 7, while the combustion gas in a high temperature state. Preheat the heat accumulator with.

Afterwards, when the set time elapses, the B-burner and the D-burner serving as the exhaust vents burn, and the A-burner and C-burner serve as the exhaust vents, thereby preheating the regenerator with hot combustion gas.

However, the atmosphere temperature of the charging stand managed by the above industry is a structure that cannot prevent outside air from entering the heating furnace at room temperature, and when the entrance door is opened to charge the slab, the entrance of the heating furnace is completely opened while the outside is opened. A lot of cold air is introduced into the furnace. Therefore, there is a problem in that the fuel consumption due to heat loss is increased by lowering the atmosphere temperature and increasing the oxygen concentration of the charging zone.

In addition, since the minimum ambient temperature required for the ignition of the regenerative burner is not secured, it is impossible to ignite the burner automatically, and may cause equipment accidents and environmental pollution due to unstable combustion. do. In particular, there is a problem that the ambient temperature of the regenerative burner due to the intrusion of external air is lowered, whereby the combustion becomes unstable.

In order to solve problems such as equipment accidents or environmental pollution that may occur when combustion is unstable, expensive pilot burners are installed. The pilot burner is an auxiliary device for ignition stabilization and automatic ignition of regenerative burners.

The present invention is to solve the above-mentioned problems, in order to improve the combustion efficiency of the regenerative burner heating system by installing a partition to suppress the intrusion of external air in the lower part of the charging zone, the combustion section of the heating furnace side by reducing the atmosphere temperature and oxygen It is an object of the present invention to provide a regenerative burner for improving combustion efficiency which prevents an increase in concentration and at the same time prevents an unstable burn demand of the regenerative burner.

The above object is a furnace inlet through which the slab is introduced, a charging zone that is heated while passing the slab sequentially after passing through the furnace inlet, a preheating zone for preheating the slab, and the slab passing through the preheating zone. The slab consists of a heating table for heating the target temperature, a cracking table for homogenizing the slab passing through the heating table, and a partition for preventing the inflow of external air at the moment the slab is introduced between the charging table and the preheating table. In a regenerative burner heating system for producing a coil after heating to a target temperature, by installing a plurality of partitions at predetermined intervals at the lower boundary of the furnace entrance to which the slab is moved and the charging zone where the slab is heated. The slab is introduced into the regenerative burner heating system that blocks the inlet of the outside air inlet by opening the furnace opening Is achieved.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

Figure 4 is a view showing the entire furnace structure according to the present invention, Figure 5 is a plan view showing the entire furnace structure according to the present invention, Figure 6 is a side view showing the charging unit structure according to the present invention. 7 is a view showing the structure of the charging stand according to the present invention, Figure 8a, b is a photograph showing the installation status of the partition according to the present invention, Figure 9 is the installation of a partition wall designed in six blocks according to the present invention It is a figure which showed the specification.

The partition 15 is installed on the lower boundary line that separates the furnace entrance 10, which is the entrance of the heating furnace, and the charging station 11 in which the regenerative burner operates, and the entrance passage, which is the entrance space of the charger, when the slab is charged. 16) Four places, two partitions 17 having a height of 1300 mm, a width of 1100 mm, and a thickness of 250 mm, and four partitions 18 having a height of 1,300 mm, a width of 1,250 mm and a thickness of 250 mm. By installing in a straight form with respect to the direction, the phenomenon that external cold air penetrates into the heating furnace is suppressed. On the other hand, in the partition 15, refractory bricks are stacked in a vertical direction, and a charging machine entry passage 16 is formed between the refractory bricks. In addition, the furnace entrance is opened and closed by the entrance door 42.

This makes it possible to stably control the atmosphere temperature of the charging station and to save energy, and to secure the ambient temperature necessary for stable ignition and automatic ignition of the burner even without installing the pilot burner, which is an ignition auxiliary device for the regenerative burner. It is possible to prevent facility accidents and environmental pollution by eliminating combustion factors.

By the way, in installing the regenerative burner for improving the combustion efficiency according to the present invention, it is necessary to change the structure of the furnace, there were some problems to be solved. For example, when the internal pressure of the furnace is changed due to the change of the internal structure of the furnace, instability of the furnace pressure control due to the fluctuation of the combustion gas flow, unevenness of the temperature distribution, and the long stroke that the charging device enters the furnace. It was necessary to solve the shaking point of the charging machine and the production failure caused by the interference with the partition. In order to solve this technical problem, through the simulation of the flow change at various locations, the installation location, arrangement shape, size, etc. of the partitions were designed, and the size of the charging machine entrance space was optimized.

10 is a view showing a position measuring the change in the ambient temperature change of the heat storage burner, Figure 11 is a view showing the temperature change according to the conventional entrance door opening and closing, Figure 12a shows the trend of the ambient temperature change in the absence of the footage FIG. 12B is a view showing a change in atmosphere temperature when there is a footage, and FIGS. 13A and 13B show a measurement position of an ambient temperature and an oxygen concentration change, and FIG. 13C is a reconstruction of a conventional heating furnace. It is a figure which compared the change of the atmospheric temperature of a heating furnace, and FIG. 13D is a figure which compares the oxygen concentration change of the conventional furnace and the remodeling furnace.

Figure 11 shows the laboratory data of the change in the ambient temperature due to the intrusion of the outside air according to the opening and closing of the furnace door before applying the present invention. The atmosphere temperature 19 of the measurement point 1 and the atmosphere temperature 20 of the measurement point 2 show a big change due to the opening and closing of the entrance door to the heating furnace.

This phenomenon is that when the entrance door is opened to charge the slab as described above, as shown in FIG. 3, a length of 14,000 mm, which is the combustion section at the entrance of the furnace, is completely opened, and a considerable amount of external air penetrates into the furnace. As the temperature decreases and the oxygen concentration increases, the internal temperature control of the charging station becomes unstable. In addition, ignition instability and automatic ignition do not occur when alternating combustion or re-ignition of the regenerative burner causes equipment accidents or environmental pollution.

12A and 12B are simulation results of two-dimensional simulation of the difference between the ambient temperature change 21 of the conventional heating furnace without partitions and the ambient temperature change of the retrofitted heating furnace with partitions under the condition that the entrance door of the heating furnace is opened. . Table 1 below shows the change in the atmosphere temperature with or without partitions, and Table 2 shows the change in oxygen concentration with or without partitions.

Number of measurements Charging station retrofit furnace Conventional furnace Measuring point 3, 4 Measurement point 1,2 Measuring point 3, 4 Measuring point 1,2 One 43 75 95 90 2 50 85 105 105 3 32 63 80 99 4 45 75 115 100 5 50 60 125 115 Average 44 71.6 104 101.8

Number of measurements Charging station retrofit furnace Conventional furnace Instrument point 3,4 Measurement point 1,2 Instrument point 3,4 Measurement point 1,2 One 7.5 7.5 9.2 7.9 2 9.5 7.8 10.5 8.1 3 8.9 5.9 8.2 7.6 4 9 7.2 10.6 8.5 5 9.1 7 11 9.1 Average 8.8 7.08 9.9 8.24

In the case of the conventional heating furnace without the partition of Figure 12a it can be seen that the intrusion air affects the deep inside the heating furnace to significantly reduce the atmosphere temperature, in particular, the lower part of the heating furnace was severely affected. On the other hand, it can be seen that in the case of a remodeled heating furnace in which a partition is installed, the air temperature is prevented from being lowered by blocking external air from entering in advance.

When the entrance door is opened by installing a partition at the lower part of the furnace, the fuel consumption is increased by restraining the heat loss of the charging zone due to the decrease in the ambient temperature and the increase of the oxygen concentration when the outside air at room temperature enters the furnace. To prevent it.

On the other hand, the measurement points 1, 2, 3, 4 are the locations where the experimental data were collected, and the ambient temperature decreases by an average of 60 ° C between the measurement points 3,4 (25) and an average of 30 ° C between the measurement points 1,2 (26). It can be seen that the amount of oxygen decreases, and the change in oxygen concentration is between 9.9% (29) of the conventional heating furnace and 8.8% (30) of the remodeling heating furnace between the measuring points 3 and 4 (27), and between the measuring points 1,2 (28). It can be seen that the oxygen concentration increase of about 1.1% is decreasing from 8.24% (31) of the furnace to 7.08% (32) of the retrofit furnace.

According to the present invention, by installing a partition in the lower part of the furnace side, it is possible to suppress the generation of heat loss of the charging zone due to external air invasion, thereby improving the combustion efficiency and increasing the fuel consumption of the regenerative burner. In addition, by stabilizing the charging atmosphere temperature control, there is an effect to enable the ignition stabilization and automatic ignition of the regenerative burner without installing a pilot burner.

Claims (1)

The furnace entrance into which the slab flows in, the charging zone that is heated while passing the slab sequentially after passing through the furnace entrance, the preheating zone for preheating the slab, and the slab passing through the preheating zone to a target temperature. The slab is heated to a heating zone, a cracking zone for homogenizing the slab passing through the heating zone, and a partition for preventing the inflow of external air at the moment when the slab flows between the charging zone and the preheating zone, thereby heating the slab to a target temperature. In a regenerative burner heating system for producing a post coil, The slab is introduced into the furnace opening through which the slab is moved, and the slab is introduced into the outer opening of the slab while the slab is introduced. Regenerative burner heating system to block

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