JP2009046536A - Method for adjusting temperature distribution of coke oven - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce an insufficient flow rate of air supplied for multi-stage combustion in a central part in an oven length direction. <P>SOLUTION: In operation by M gas combustion, air is replenished to a predetermined combustion chamber 2 located in the central part in the oven length direction by using a C gas supply system for air replenishment. This air replenishment is carried out by disconnecting a branch pipe 7 communicating with the predetermined combustion chamber 2 from a distributor pipe 8, and connecting an air supply source to its perpendicular piping 6. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a temperature distribution adjusting method for a coke oven.

One of the techniques for improving the combustion of coke ovens is multistage combustion that lowers the flame temperature to reduce NOx. This supplies about 80 to 90% of the air required for complete combustion at the lower part of the combustion chamber. This is a technique for supplementing the air shortage above the combustion chamber and burning it completely as a whole (see Patent Document 1).
JP 2001-81470 A

  As a structure for supplying air to the upper part for multistage combustion, an air supply path is formed in the partition wall between the combustion chambers subdivided in the furnace length direction, and air is supplied from this supply path to the combustion chamber on one side There is. However, the bricks that make up the combustion chamber are particularly prone to deterioration near the kiln entrance, so avoid the above-mentioned supply path only on the outer partition located at the extreme end in the furnace length direction. I want. Therefore, as shown in FIG. 4, the outlet of the supply passage formed in the partition wall between the combustion chamber located at the extreme end in the furnace length direction and the combustion chamber adjacent to the combustion chamber is located in the combustion chamber located at the extreme end. It must be formed toward the side, that is, the kiln opening side, and the subsequent outlet is necessarily directed to the kiln opening side. Accordingly, each outlet is formed so as to face away from the coke side and pusher side with the center in the furnace length direction as a boundary, and the supply that blows out to the coke side is only in the partition located at the center in the furnace length direction. Both the road and the supply path that blows out to the pusher side are added.

  In order to prevent the strength of the partition walls from being impaired, the two supply paths provided in the central partition have a smaller cross-sectional area than the supply paths formed in the other partitions. Therefore, in these two supply passages, the pressure loss increases as the ventilation resistance increases, the flow rate of air that can be supplied decreases, and the combustion temperature decreases. That is, when observing the temperature distribution in the furnace length direction, as shown in FIG. 5, the combustion temperature at the center portion locally decreases, and an ideal temperature distribution could not be obtained.

  An object of the present invention is to reduce an insufficient flow rate of air supplied for multistage combustion at the center in the furnace length direction.

  In order to solve the above problems, a coke oven temperature distribution adjusting method according to claim 1 of the present invention includes two fuel supply systems capable of supplying fuel gas to respective combustion chambers subdivided in the furnace length direction, In the coke oven having an air supply system capable of supplying air to each of the combustion chambers, when operating with the one fuel supply system and the air supply system, the predetermined combustion located in the center in the furnace length direction The temperature distribution in the furnace length direction of the combustion chamber is adjusted by diverting the other fuel supply system to the chamber to supply air.

  According to the temperature distribution adjusting method for a coke oven according to claim 1 of the present invention, the other fuel supply system is diverted to the predetermined combustion chamber located in the center in the furnace length direction to supply air. In the central portion in the furnace length direction, the shortage of the flow rate of the air supplied to the combustion chamber can be reduced. Therefore, it is possible to avoid a situation in which the combustion temperature at the central portion is locally lowered due to a decrease in the air flow rate, and an ideal temperature distribution can be obtained. In addition, since the existing fuel supply system is simply diverted, it can be easily realized and cost increase can be prevented.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration of a coke oven. The carbonization chamber 1 and the combustion chamber 2 are alternately arranged in the furnace group direction, and the heat storage chamber 3 is arranged in the furnace group direction below.
The combustion chamber 2 is subdivided in the furnace length direction, and as shown in FIG. 2, one combustion chamber 2 has a hairpin structure in which two vertical flues 2a and 2b arranged in the furnace length direction communicate with each other at the top. ing. The heat storage chamber 3 is divided in the furnace length direction so as to correspond to the combustion chamber 2, and a predetermined heat storage chamber 3 communicates with one combustion chamber 2. The bottom part of each heat storage chamber 3 arranged in the furnace length direction communicates with the sole flue 4 extending in the furnace length direction, and an opening is provided between each heat storage chamber 3 and the sole flue 4. A nozzle plate 5 is inserted.

  A route for supplying fuel gas (M gas: mixed gas of coke oven gas and blast furnace gas) and air to the combustion chamber 2 and a route for discharging exhaust gas from the combustion chamber 2 to one combustion chamber 2 Are individually formed. That is, M gas and air are respectively injected from one end of CS of different sole flues 4 and enter the heat storage chamber 3 through the nozzle plate 4, where they are preheated and then rise to the combustion chamber 2. Combustion is performed in one of 2b. The exhaust gas is drawn down from the other of the vertical saddles 2a and 2b to the heat storage chamber 3, where it is heat-recovered, enters the sole flue 4 and is exhausted from the other end of the PS. The M gas and air supply route and the exhaust gas exhaust route are switched every predetermined time, and in the heat storage chamber 3, preheating and heat recovery are alternately performed.

  In order to lower the flame temperature and reduce NOx, two-stage combustion is performed. The first stage supplies air from the bottom of the vertical flue, and the second stage supplies air into the partition walls between the vertical flues. The supply path 2c is formed, and air is supplied from the supply path 2c to the vertical flue on one side. That is, a predetermined heat storage chamber 3 communicates with one supply path 2c, and air sent to the heat storage chamber 3 is blown out to the vertical flue 2a or 2b through the supply path 2c in the partition wall. .

  However, since the bricks constituting the combustion chamber 2 are particularly susceptible to deterioration at the portion close to the kiln opening, avoid forming the supply path 2c only on the partition wall located outside the furnace located at the extreme end in the furnace length direction. I want. Therefore, as shown in FIG. 3, the outlet 2d of the supply passage 2c formed in the partition wall between the vertical flue located at the extreme end in the furnace length direction and the vertical flue adjacent to the vertical flue is the vertical apex located at the extreme end. It is formed toward the side of the flue, that is, the kiln opening side, and the subsequent outlets 2d are all directed toward the kiln opening side. Accordingly, each outlet 2d is formed so as to face away from the coke side and the pusher side with the center in the furnace length direction as a boundary, and blows out to the coke side only in the partition located at the center in the furnace length direction. Both the supply path 2c and the supply path 2c that blows out to the pusher side are provided. The two supply paths 2c provided in the central partition have a smaller cross-sectional area than the supply paths 2c formed in the other partitions in order to prevent the strength of the partition from being impaired.

Since the combustion temperature of each combustion chamber 2 depends on the flow rate of the M gas and air supplied thereto, the flow area of the fuel gas passing therethrough is adjusted by adjusting the opening area of the nozzle plate 5, Adjust the combustion temperature.
On the other hand, a vertical pipe 6 for supplying fuel gas (C gas: coke oven gas) communicates with the bottom of each vertical flue. As shown in FIG. 4, each vertical pipe 6 communicates with a branch pipe 8 via a branch pipe 7, and a chip 9 capable of controlling the flow rate is inserted in the branch pipe 7. Therefore, only the C gas injected into the distribution pipe 8 is supplied directly to the combustion chamber 2 without passing through the heat storage chamber 3, and combustion is performed in one of the vertical saddles 2a and 2b. The exhaust gas is the same as that during the combustion of the M gas described above.

As described above, there are M gas combustion operated by M gas and air, and C gas combustion operated by C gas and air, which are operated by any combustion, but usually operate mainly by M gas combustion. ing.
When operating by this M gas combustion, since the C gas supply system is not used and is in a resting state, this C gas supply system is diverted to a predetermined combustion chamber 2 located in the center in the furnace length direction. Supply air to That is, as shown in FIG. 5, first, the tip 9 of the branch pipe 7 communicating with the predetermined combustion chamber 2 is replaced with the blind tip 10, and the branch pipe 7 is disconnected from the distribution pipe 8. If the channel can be completely closed with the tip 9, there is no need to replace it with the blind tip 10. Then, an air supply source such as an air blower is connected to the lower end of the vertical pipe 6 disconnected from the distribution pipe 8 to replenish air. Here, the predetermined combustion chamber 2 refers to a vertical flue adjacent to a partition located at the center in the furnace length direction.

Next, the effect of this embodiment is demonstrated.
The two supply paths 2c provided in the central partition have a smaller cross-sectional area than the supply paths 2c formed in the other partitions in order to prevent the strength of the partition from being impaired. However, if the cross-sectional area is reduced in this way, no matter how much the opening area of the nozzle plate 5 is increased, the pressure resistance increases as the ventilation resistance of the supply path 2c itself increases, and the flow rate of air that can be supplied decreases. And combustion temperature will fall. That is, when the temperature distribution in the furnace length direction is observed, the combustion temperature at the center portion is locally reduced, and an ideal temperature distribution cannot be obtained mainly during M gas combustion.

  Therefore, when operating by M gas combustion, the C gas supply system is diverted to the predetermined combustion chamber 2 located in the center in the furnace length direction to replenish the air, thereby the center in the furnace length direction. This can compensate for the insufficient flow rate of the air supplied to the combustion chamber 2. Therefore, it is possible to avoid a situation in which the combustion temperature at the central portion is locally lowered due to a decrease in the air flow rate, and an ideal temperature distribution can be obtained.

  In addition, since the existing C gas supply system is simply diverted, it can be easily realized and cost increase can be prevented. That is, it is possible to supply air by simply disconnecting the branch pipe 7 communicating with the predetermined combustion chamber 2 from the distribution pipe 8 and connecting an air supply source to the vertical pipe 6.

It is a schematic structure of a coke oven. Supply and exhaust routes. It is a schematic structure of a supply path and a blower outlet. This is an existing C gas supply path. This is the C gas supply route. It is a conventional temperature distribution.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbonization chamber 2 Combustion chamber 2a, 2b Vertical flue 2c Supply path 2d Outlet 3 Thermal storage chamber 4 Sole flue 5 Nozzle plate 6 Vertical piping 7 Branch pipe 8 Dividing piping 9 Tip 10 Blind tip

Claims (1)

  A coke oven having two fuel supply systems capable of supplying fuel gas to each combustion chamber subdivided in the furnace length direction and an air supply system capable of supplying air to each of the combustion chambers. When operating with the supply system and the air supply system, the combustion chamber is replenished to the predetermined combustion chamber located in the center in the furnace length direction by using the other fuel supply system to supply air. A temperature distribution adjusting method for a coke oven, characterized in that the temperature distribution in the furnace length direction is adjusted.

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