JP2015157896A - Operation method of coke oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation method of a coke oven capable of properly supplying a fuel gas to continue proper operation even in heat accumulation chamber abnormalities and oven maintenance.SOLUTION: A coke oven 100 includes a plurality of carbonization chambers 11 for carbonizing coal, a plurality of combustion chambers 12 for heating the carbonization chambers 11 by burning a fuel gas supplied to the combustion chambers 12, the fuel gas composed of a blast furnace gas, a coke oven gas, and a mixed gas thereof, both the chambers being alternately arranged, and further includes a heat accumulation chamber 13 for heat accumulating a predetermined fuel gas. In controlling supply of the fuel gas in operation, heating of each carbonization chamber 11 can be controlled by controlling the kind and the flow rate of the fuel gas supplied to each combustion chamber 12. The kind and the flow rate of the fuel gas supplied to the combustion chamber 12 are controlled in accordance with the state of the heat accumulation chamber 13 or the state of the carbonization chamber 11.

Description

  The present invention relates to a method for operating a coke oven that operates by controlling the supply of fuel gas used when heating coal in a plurality of carbonization chambers of the coke oven.

  Conventionally, steelworks have reused by-products generated in the facilities in order to save energy. The same applies to the fuel gas used in the coke oven. Blast furnace gas (hereinafter referred to as B gas) generated in the blast furnace, coke oven gas (hereinafter referred to as C gas) generated in the coke oven, etc. are used as fuel gas for the coke oven. Use as Further, in normal operation, a mixed gas (hereinafter referred to as M gas) in which C gas having a large calorific value and B gas having a small calorific value are mixed may be used as a fuel gas (see, for example, Patent Document 1). . This is because there is a demand to use C gas with a large calorific value in other facilities in the steelworks, and to compensate for the shortage of fuel gas supply.

  A typical chamber-type coke oven has a charcoal chamber (also referred to as a kiln) in which coal is charged and carbonized, and a combustion chamber in which fuel gas is combusted to heat the carbonization chamber. Below these, a heat storage chamber for preheating fuel gas and air supplied to the combustion chamber is provided (see, for example, Patent Document 2).

  In a conventional two-split type coke oven, the heat storage chamber and the combustion chamber are divided into two at almost the center of the coke oven. , CS). In combustion of fuel gas, CS and MS are alternately switched every predetermined time (usually 20 to 30 minutes), preheating heat storage is repeated, and operation with improved thermal efficiency is performed (for example, Patent Document 3). Usually, the combustion direction is switched collectively for each half furnace group with the coal tower as a boundary (for example, Patent Document 4).

  On the other hand, when B gas and M gas are combusted among the above fuel gases (B gas combustion or M gas combustion), as shown in Patent Document 2, the fuel gas and the combustion air are individually stored in the heat storage chamber. Both are mixed and combusted in the combustion chamber after being supplied to the heat storage chamber and preheated, but when C gas is combusted (C gas combustion), since the C gas is in a heated state, it does not pass through the heat storage chamber. Is supplied to the lower horizontal flue located at the upper part of the heat storage chamber and at the lower part of the combustion chamber, and only the combustion air passes through the heat storage chamber.

  The combustion control of the coke oven is a constant furnace temperature control system that changes the fuel gas flow rate so that the combustion chamber temperature (generally referred to as the furnace temperature) is maintained at a predetermined value, and the calorie amount (calorie) per unit flow rate is predetermined. A gas calorie constant control method for changing the fuel gas flow rate so as to keep the value can be cited (for example, see Patent Document 5). These controls are used in combination according to the operation status to reduce the unit of dry distillation heat intensity.

JP-A-60-203696 JP 7-268327 A Japanese Patent Laid-Open No. 1-259085 Japanese Patent Laid-Open No. 2-311595 JP 7-19453 A

  By the way, conventionally, the same type of gas is used for each furnace group, such as B gas, M gas, and C gas, for each furnace group. However, when there is an abnormality in the heat storage chamber, the B gas and M gas must pass through the heat storage chamber and be preheated, so that they cannot be used as fuel gas. At this time, if a furnace group having an abnormal heat storage chamber is going to use B gas or M gas, if C gas is required for all the furnace groups, other equipment in the ironworks also needs C gas. The energy balance in the steelworks is disrupted, the supply of C gas is tight, and in the worst situation, other facilities are supposed to be stopped.

  On the other hand, when the kiln constituting the carbonization chamber is aged, the bricks are individually replaced. At this time, if the fuel gas of the furnace group to which the target kiln belongs is B gas or M gas, It is necessary to throttle the cock for adjusting the supply amount of B gas or M gas in the combustion chamber. However, when the cock is squeezed, the supply amount of B gas or M gas supplied to the opposite kiln adjacent to the combustion chamber also decreases, the furnace temperature decreases, the heat-resistant brick deteriorates, the coal retorting time increases, It will cause clogging at the time of dry distillation coke extrusion.

  In order to prevent these problems, it is conceivable to manually adjust the butterfly valve installed in the C gas main, but in that case, follow the gas calorie that varies depending on the operating conditions. This makes it impossible to control the combustion of the coke oven.

  The present invention has been made in view of such circumstances, and a coke oven operating method capable of appropriately supplying fuel gas and performing appropriate operation even in the case of abnormality in a heat storage chamber or in repairing a kiln. It is an issue to provide.

  In order to solve the above problems, the present invention provides the following (1) to (3).

(1) A plurality of carbonization chambers for carbonizing coal, and a plurality of combustions for supplying blast furnace gas, coke oven gas, and mixed gas thereof as fuel gas and heating the carbonization chamber by combustion of fuel gas A coke oven having a heat storage chamber in which these are alternately arranged and further storing a predetermined fuel gas, and the operation is performed by controlling the supply of the fuel gas,
The type and flow rate of the fuel gas supplied to each combustion chamber is controlled to enable heating control for each carbonization chamber, and depending on the state of the heat storage chamber or the state of the carbonization chamber, the corresponding combustion chamber is provided. A method for operating a coke oven, wherein the operation is performed by controlling the type and flow rate of the fuel gas to be supplied.

  (2) When a specific gas cannot be supplied to a part of the combustion chambers or a specific amount of a specific gas cannot be supplied, control is performed so that another fuel gas is supplied to the combustion chamber as an alternative. The method for operating a coke oven as described in (1) above.

  (3) Dividing a plurality of carbonization chambers and a plurality of combustion chambers into a plurality of small-scale furnace groups, and controlling the type and flow rate of fuel gas for each small-scale furnace group, In small-scale furnace groups that supply blast furnace gas, or mixed gas of blast furnace gas and coke oven gas, blast furnace gas or a mixed gas of blast furnace gas and coke oven gas cannot be supplied to some combustion chambers, or these When the required amount of gas cannot be supplied, the coke oven operating method according to (2), wherein the coke oven gas is supplied to the small scale furnace as an alternative.

  According to the present invention, since the type and flow rate of the fuel gas can be controlled for each combustion chamber, the fuel gas is appropriately supplied according to the operation state even when the heat storage chamber is abnormal or when repairing the kiln. Can operate properly. Further, when implementing the present invention, it is possible only by switching the valve using the existing piping, and it is not necessary to remodel the piping system, so that the remodeling cost can be reduced.

It is a schematic block diagram which shows the coke oven equipment for enforcing the operating method of the coke oven which concerns on one Embodiment of this invention. It is a figure which shows the flow of the fuel gas in a coke oven. It is a figure which shows the outline | summary of the combustion control at the time of M gas combustion. It is a figure which shows the outline | summary of the combustion control at the time of C gas combustion.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic configuration diagram showing a coke oven facility for carrying out a coke oven operating method according to an embodiment of the present invention.

  The coke oven facility 1 includes a coke oven 100, a combustion gas supply system 200, and a control unit 300.

  In the upper part of the coke oven 100, a carbonization chamber 11 in which coal is charged and carbonized, and a combustion chamber 12 in which fuel gas is combusted to heat the carbonization chamber are alternately arranged. A heat storage chamber 13 for preheating fuel gas and air to be supplied to the chamber is arranged, and further includes a gas introduction portion 14 and an exhaust portion 15 for introducing the fuel gas.

  The carbonization chambers 11 and the combustion chambers 12 are alternately arranged adjacent to each other to form a small scale furnace group, and a plurality of such small scale furnace groups are further provided to form a large scale furnace group. .

  The coke oven 100 is of a two-part type, and is divided into two at the center of the heat storage chamber 13 and the combustion chamber 12 into an extruder-side MS and a fire extinguisher-side CS. The gas supply unit 14 and the CS gas supply unit 14 are periodically switched to supply fuel gas alternately.

  The combustion gas supply system 200 includes a C gas dedicated pipe 41 for supplying C gas, an M gas pipe 42 for supplying M gas obtained by mixing B gas and C gas, and C gas to the M gas pipe 42. And an increased C gas pipe 43 for adding. In the C gas dedicated pipe 41, a pressure gauge 51, a flow meter 52, a butterfly valve 53, and a pressure gauge 54 are provided in this order from the upstream side. The M gas pipe 42 is provided with a pressure gauge 55, a flow meter 56, a butterfly valve 57, and a pressure gauge 58 in order from the upstream side. Further, the C increasing gas pipe 43 is provided with a flow meter 59 and a butterfly valve 60. The C gas dedicated pipe 41 is branched to a C gas branch pipe 61 connected to each combustion chamber 12. Further, the M gas pipe 42 is branched to an M gas branch pipe 62 connected to each combustion chamber 12. Each C gas branch pipe 61 is provided with a C gas flow rate adjustment cock 63 for adjusting the flow rate of the C gas supplied to each combustion chamber 12. Each M gas branch pipe 62 is provided with an M gas flow rate adjustment cock 64 for adjusting the flow rate of the M gas supplied to each combustion chamber 12.

  In FIG. 1, for the sake of convenience, in the combustion gas supply system 200, a branch part to the C gas branch pipe 61 of the C gas dedicated pipe 41 and a branch part to the M gas branch pipe 62 of the M gas pipe 42 are drawn. Actually, these branch portions exist inside the gas introduction portion 14 of the coke oven 100.

  As shown in FIG. 2, a C gas dedicated pipe 41 and an M gas pipe 42 extend in the gas introduction part 14 of the coke oven 100, and the C gas branch pipe 61 and the M gas branch are respectively provided in the gas introduction part 14. The pipe 62 is branched. The C gas branch pipe 61 is connected to an upper horizontal flue 65 extending horizontally between the combustion chamber 12 and the heat storage chamber 13, and the M gas branch pipe 62 is a lower horizontal flue extending horizontally below the heat storage chamber 13. 66. The lower horizontal flue 66 is provided with a damper 67 for taking in air for combustion, and air is taken in by opening the damper 67. In the case of M gas combustion, M gas and air are supplied to the individual heat storage chambers 13 and preheated, and then supplied to the combustion chamber 12. In the case of C gas combustion, C gas is supplied to the combustion chamber 12 via the upper horizontal flue 65 without passing through the heat storage chamber 13, and only combustion air passes through the heat storage chamber 13 to the combustion chamber 12. To be supplied. It is also possible to supply M gas and C gas at the same time for simultaneous combustion.

  The exhaust section 15 includes an exhaust path 71 connected to the lower horizontal flue 66, a small flue 72 connected to the exhaust path 71, a large flue (not shown) in which the small flue 72 is assembled, a large flue A chimney (not shown) connected to the flue. A switching damper 68 is provided between the lower horizontal flue 66 and the exhaust path 71.

  The control unit 300 controls the type and flow rate of the combustion gas. At this time, both the control for each furnace group and the control for each combustion chamber 12 are possible. The control at this time is a constant furnace temperature control for changing the fuel gas flow rate or the like so that the temperature of the combustion chamber 12, that is, the furnace temperature, is maintained at a predetermined value in both the C gas combustion and the M gas combustion. In addition, the gas calorie constant control for changing the fuel gas flow rate and the ratio so as to keep the calorie amount (heat amount) per unit flow rate at a predetermined value can be combined and operated depending on the operation status. As a result, it is possible to reduce the unit of dry distillation calorific value. Further, by inputting the type of fuel gas used for each combustion chamber 12 to the control unit 300, the flow rate of the fuel gas and the like can be automatically controlled. Further, the fuel gas and the flow rate thereof can be automatically controlled for each combustion chamber 12 by inputting the state for each kiln (carbonization chamber 11) and the state for each heat storage chamber 13 to the control unit 300. It is also possible to burn both M gas and C gas in the predetermined combustion chamber 12.

  In actual operation, when performing combustion control during M gas combustion, as shown in FIG. 3, in the furnace temperature constant control, the average furnace temperature is calculated, and the calculated value is compared with the target temperature. Find the deviation, change the flow rate or back pressure of the M gas so that the furnace temperature becomes the target value, and in the calorie constant control, the ratio to make the calorie constant based on the calorie calculation actual value of C gas and M gas Calculate and change the ratio of M gas and C gas and the flow rate.

  In addition, when performing combustion control during C gas combustion, as shown in FIG. 4, in the furnace temperature constant control, the average furnace temperature is calculated, and the calculated value is compared with the target temperature to obtain a deviation, The flow rate or back pressure of C gas is changed so that the furnace temperature becomes the target value, and in the calorie constant control, the flow rate of C gas is changed based on the actual calorie calculation value of C gas.

  In the case where mixed combustion is performed by supplying M gas and C gas, control that compromises the combustion control is performed.

  In normal cases, the coke oven can be operated by controlling the type and flow rate of the fuel gas for each large-scale furnace group as usual.

  However, for example, in a large-scale furnace group for M gas combustion, when an abnormality occurs in the heat storage chamber 13 corresponding to some of the combustion chambers 12, M gas cannot be supplied to the combustion chambers 12, so that In this control, it is necessary to control the supply of C gas that does not need to pass through the heat storage chamber 13 to all the combustion chambers 12 of the large-scale furnace group, and a large amount of C gas is required. On the other hand, in this embodiment, since control for each combustion chamber 12 is possible, information indicating that some of the heat storage chambers 13 are abnormal is input to the control unit 300 automatically or by an operator. In 300, only the corresponding combustion chamber 12 is switched to C gas not passing through the heat storage chamber 13, and supplied instead of M gas. At this time, the flow rate of the C gas can be controlled for the corresponding combustion chamber 12 in order to keep the furnace temperature or calories constant. Further, the heat storage chamber 13 can be repaired while the C gas is being supplied, and at the same time, it is not necessary to switch all the combustion chambers 12 belonging to the furnace group to which the M gas is to be supplied to the C gas. The energy balance in the steelworks is not disrupted.

  Conventionally, when repairing an old kiln in the carbonization chamber 11 (replacement of bricks) in a large-scale furnace group for M gas combustion, conventionally, the supply amount of M gas in the combustion chamber 12 near the kiln However, when the cock is squeezed, the amount of M gas supplied to the kiln on the opposite side adjacent to the combustion chamber 12 also decreases, the furnace temperature decreases, and the heat-resistant brick deteriorates. In addition, prolonged coal carbonization time and clogging during extrusion of coking coke were incurred. On the other hand, in this embodiment, since each combustion chamber 12 can be controlled, information indicating that some of the carbonization chamber kilns are being repaired is input to the control unit 300 automatically or by the operator. The unit 300 controls the M gas adjustment cock of the combustion chamber 12 in the vicinity of the target kiln, and at the same time controls to supply C gas as an alternative to the decrease in M gas, thereby reducing the calorie of the combustion gas. Can be held. For this reason, stable operation by preventing the furnace temperature of the kiln (carbonization chamber 11) on the opposite side of the combustion chamber 12, deterioration of heat-resistant bricks, prolonged coal dry distillation time, clogging during dry distillation coke extrusion, etc. Can be maintained.

  Further, in the present embodiment, by inputting the type of fuel gas used for each combustion chamber 12 to the control unit 300, the flow rate of the fuel gas can be automatically controlled, and the fuel gas type is matched with the type of fuel gas. In addition, by inputting to the control unit 300 whether the state of each kiln (carbonization chamber 11) is a normal state, a clogged state, or an empty kiln containing no coal, it is adjacent thereto. The fuel gas flow rate and ratio can be controlled for each combustion chamber 12. Thereby, it becomes possible to follow the fluctuation of the operation status and the fluctuation of the gas calorie corresponding thereto. As a result, it is possible to prevent the input heat amount from being insufficient or the input heat amount from being excessive. Further, it is possible to control the fuel gas and the flow rate for each combustion chamber without assuming the control for each large-scale furnace group.

  In addition, a small-scale furnace group in which a plurality of carbonization chambers and combustion chambers are alternately arranged may be formed, and the fuel gas and the flow rate may be controlled for each small-scale furnace group.

  Moreover, although the case where M gas and C gas were used as combustion gas was shown in the said embodiment, the case where B gas is used instead of M gas is the same. However, when B gas is used, ratio control is not necessary.

1 Coke oven equipment 11 Carbonization chamber (kiln)
12 Combustion chamber 13 Heat storage chamber 14 Gas supply section 15 Exhaust section 41 C gas dedicated pipe 42 M gas pipe 43 Increased C gas pipe 51, 54, 55, 58 Pressure gauge 52, 56, 59 Flowmeter 53, 57, 60 Butterfly valve 61 C gas branch pipe 62 M gas branch pipe 63 C gas flow rate adjustment cock 64 M gas flow rate adjustment cock 100 Coke oven 200 Fuel gas supply system 300 Control unit

Claims (3)

A plurality of carbonization chambers for carbonizing coal, and a plurality of combustion chambers for supplying blast furnace gas, coke oven gas, and mixed gas thereof as fuel gas and heating the carbonization chamber by combustion of fuel gas. A coke oven in which these are alternately arranged and further has a heat storage chamber for storing a predetermined fuel gas, and the operation method of the coke oven that operates by controlling the supply of the fuel gas,
The type and flow rate of the fuel gas supplied to each combustion chamber is controlled to enable heating control for each carbonization chamber, and depending on the state of the heat storage chamber or the state of the carbonization chamber, the corresponding combustion chamber is provided. A method for operating a coke oven, wherein the operation is performed by controlling the type and flow rate of the fuel gas to be supplied.   When a specific gas among the fuel gases cannot be supplied to a part of the combustion chambers or when a specific amount of a specific gas cannot be supplied, control is performed so that another fuel gas is supplied to the combustion chamber as an alternative. The method for operating a coke oven according to claim 1.   A plurality of carbonization chambers and a plurality of combustion chambers are divided into a plurality of small-scale furnace groups, each of which is operated by controlling the type and flow rate of the fuel gas. Or, in a small-scale furnace group that supplies mixed gas of blast furnace gas and coke oven gas, some combustion chambers cannot supply blast furnace gas or mixed gas of blast furnace gas and coke oven gas, or these gases cannot be supplied. 3. The method of operating a coke oven according to claim 2, wherein when the required amount cannot be supplied, the coke oven gas is controlled to be supplied as an alternative to the small scale furnace group.

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