KR101395508B1 - Apparatus for controlling combustion of furnace with oxygen lancing - Google Patents

Abstract

The present invention relates to an apparatus for controlling combustion of a furnace with oxygen lancing that additionally supplies oxygen together with air as an oxidizing agent of injected fuel, so that the quantity of NOx generated can be reduced, unlike the conventional practice wherein NOx is discharged in large quantities due to the increment of N2 in the air used as a single oxidizing agent. According to the present invention, the apparatus includes a heating furnace having a combustion chamber formed at the inside thereof so as to accommodate a material to be heated thereinto, a burner disposed in the heating furnace and receiving fuel and air to conduct the combustion of the combustion chamber, a fuel supply line supplying the fuel to the burner, an air supply line supplying the air to the burner, an oxygen supply line directly supplying oxygen to the interior of the combustion chamber of the heating furnace, and a combustion controller connected to the fuel supply line, the air supply line and the oxygen supply line, respectively, receiving an atmosphere temperature inside the combustion chamber and controlling the flow rate of the fuel and the flow rates of the air and oxygen as oxidizing agents supplied to the burner and the combustion chamber of the heating furnace to reach a target temperature.

Description

TECHNICAL FIELD [0001] The present invention relates to an apparatus for controlling combustion of oxygen in a heating furnace,

The present invention is characterized in that when a heating material is accommodated in a combustion chamber in a heating furnace and then fuel and oxidizer are supplied to the burner installed in the heating furnace and burned in the combustion chamber, And more particularly to an oxygen lancing combustion control apparatus for a heating furnace capable of controlling the combustion.

Generally, in a steel process, a furnace is a device for uniformly heating a heating material such as a slab, a bloom, a billet, or the like so as to be rolled in a post-process. Such a heating furnace usually has a preheating zone, a heating zone and a crack, and each sets the atmospheric temperature in consideration of the target temperature for extracting the material and the residence time in the furnace.

In order to adjust the atmospheric temperature in the furnace, fuel and oxidant, air are injected through the burner and burned in the furnace to adjust the ambient temperature. In this case, the fuel used as a heat source is usually mixed with COG (Coke Oven Gas) and Blast Furnace Gas (BFG), LDG (Linz Donavitz Gas) or Liquefied Natural Gas (LNG) generated in the blast furnace. At this time, it is necessary to control the amount of air proportional to the injected fuel to be the complete combustion of the fuel according to the stoichiometric air-fuel ratio.

That is, oxygen (O ₂ ) in the air is required for the reaction between the carbon (C) and the hydrogen (H) contained in the fuel, and the combustion reaction is performed by supplying fuel and air through the burner do. The supply when air is excessively increased by the combustion gas energy loss increases from the exhaust gas, and the combustion temperature is lowered and the thermal efficiency decreases, because the heat capacity decreased, the discharge of NO _X due to nitrogen (N ₂₎ increases in the air . Conversely, if the supplied air is too small, the loss due to the incomplete combustion of the fuel increases, and the combustion efficiency, that is, the conversion ratio from the chemical energy to the thermal energy, decreases, and the emission of carbon monoxide and unburned hydrocarbons increases.

However, the actual amount of air supplied for the complete combustion of the fuel injected into the furnace is slightly more than the stoichiometric air-fuel ratio of the fuel. This is because the amount of oxygen in the air is further increased That's why you need it. That is, to say the air ratio is the actual input, including an additional amount of oxygen necessary to the excess air ratio (u), is multiplied by the excess air ratio (u) to the theoretical amount of air (A _o) corresponding to the stoichiometric air-fuel ratio is the amount of air introduced in the actual furnace .

For example, assuming that the theoretical air / fuel ratio of a specific heated material is 1 to 10, the total amount of fuel to the theoretical air amount (A _o ) However, in practice, when only the theoretical air amount Ao is input, the complete combustion of the fuel does not occur, and therefore, the amount of air required for the amount of oxygen to be added is further needed. Therefore, the amount of air to be actually injected for complete combustion with respect to the supplied fuel amount 1 is obtained by multiplying the theoretical air amount Ao by the excess air ratio u. That is, if the theoretical air amount Ao is 10 and the excess air ratio u is 1.2, the actual amount of air to be injected should be 12, so that the complete combustion of the fuel amount 1 occurs.

An apparatus for controlling a combustion furnace according to the above-described prior art is shown in Figs. As shown in Fig. 1, a conventional combustion furnace combustion control apparatus includes a heating furnace 1 in which a heating material (not shown) is accommodated in an internal combustion chamber 1a, A burner 2 for receiving fuel and air and burning the combustion chamber 1a of the heating furnace 1; a fuel supply line 3 for supplying fuel to the burner 2; And an air supply line 4 connected to the fuel supply line 3 and the air supply line 4 so as to receive the ambient temperature inside the combustion chamber 1a and to reach a target temperature to be converted And a combustion control unit 5 for controlling the flow rates of fuel and air supplied to the burner 2.

Usually, two temperature sensors are installed in the heating furnace 1 so as to detect the atmospheric temperature inside the combustion chamber 1a. The two signals detected by the temperature sensor are used as an average temperature, 1 is set to the atmospheric temperature inside the combustion chamber 1a. The combustion control unit 5 receives the ambient temperature of the combustion chamber 1a and controls the flow rate of each of the fuel and air supplied to the burner 2 so as to reach the target temperature to be converted.

2, the combustion control unit 5 receives the atmospheric temperature of the combustion chamber 1a, compares the atmospheric temperature with the target temperature, and outputs a temperature set value tic_out A fuel change selector (12) for receiving the temperature set value (tic_out) from the temperature instruction adjuster (11) and determining the increase / decrease amount of the fuel; A fuel flow rate indication regulating section 13 for regulating a fuel flow rate supplied from the fuel supply line 3 to the burner 2 according to the amount of increase / decrease of the fuel determined from the temperature indication regulating section 11; (14) for receiving the temperature set value (tic_out) and converting it into an air flow rate conversion value [f (x1)] to determine an increase / decrease amount of the air; To adjust the air flow rate from the air supply line (4) It comprises the indicated air conditioning unit (15). At this time, the fuel increase / decrease selection unit 12 receives the signal of the fuel flow rate conversion value [f (x2)] according to the increase / decrease amount of the air and determines the increase / decrease amount of the fuel determined according to the temperature setting value tic_out And the air increase / decrease selection unit 15 receives the signal of the air flow rate conversion value F (x3) corresponding to the increase / decrease amount of the fuel, Feedback control of weight loss.

That is, the temperature set value tic_out output by the temperature instruction adjusting unit 11 is a difference value of the target temperature to be converted from the atmospheric temperature of the combustion chamber 1a of the heating furnace 1, (+) When it is large (-), and whether to increase or decrease the combustion load. Therefore, the increase / decrease rate of the fuel flow rate and the increase / decrease rate of the air flow rate are determined according to the temperature set value.

The combustion control apparatus of the heating furnace according to the above-mentioned conventional technique is a double-cross control by fuel to air, and substantially full combustion inside the combustion chamber Ia for fuel injected as previously mentioned The amount of air should be added to the theoretical air amount (A _o ) by the excess air ratio (u). Further, the amount of air to be added is an additional amount of oxygen, which causes a problem that the amount of NO _x increases due to the increase of nitrogen (N ₂ ) in the air together with oxygen.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the above-described problems and provide a fuel cell system and a fuel cell system, which are capable of reducing NO _x emissions due to an increase in nitrogen (N ₂ ) And to provide an oxygen lancing combustion control device for a furnace capable of reducing the generation of NO _x by supplying oxygen.

Particularly, when oxygen, which is an oxidant, is supplied separately from air, oxygen is directly supplied into the combustion chamber of the heating furnace without supplying oxygen through the burner, whereby the complete combustion of the fuel can be efficiently achieved, And to provide an oxygen lancing combustion control device for a heating furnace capable of reducing the amount of fuel gas.

On the other hand, a heating furnace capable of optimally feedback-controlling the amount of fuel, air, and oxygen supplied through a triple-cross control that can automatically control the flow rate of supplied fuel, air and oxygen, And an oxygen lancing combustion control device.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments with reference to the accompanying drawings.

In order to accomplish the above object, an apparatus for controlling combustion of oxygen lancing in a heating furnace according to the present invention comprises a heating furnace in which a heating material is accommodated in an internal combustion chamber, a heating furnace installed in the heating furnace, A burner for burning the combustion chamber of the heating furnace; a fuel supply line for supplying fuel to the burner; an air supply line for supplying air to the burner; and an oxygen supply unit for directly supplying oxygen into the combustion chamber of the heating furnace Line and the combustion chamber of the burner and the heating furnace, respectively, connected to the fuel supply line, the air supply line and the oxygen supply line, respectively, so as to receive the ambient temperature inside the combustion chamber and reach a target temperature to be converted And a combustion control unit for controlling the flow rates of air and oxygen which are the oxidant and the fuel, respectively.

The combustion control unit may further include a temperature indication adjusting unit for receiving the atmospheric temperature of the combustion chamber and comparing the atmospheric temperature with the target temperature to output a temperature setting value tic_out, And a fuel flow rate indication adjusting unit for adjusting a fuel flow rate supplied from the fuel supply line to the burner according to the amount of increase / decrease of the fuel determined by the fuel increase / decrease unit, An oxidizer increase / decrease selection unit for receiving the temperature set value tic_out from the temperature indicating control unit and determining the increase / decrease amount of the oxidizer; and a control unit for controlling the air / And an oxidizer linkage adjusting unit for adjusting the oxygen flow rate in association with each other, And the oxidizer increase / decrease selector selects the oxidizer increase / decrease amount based on the fuel amount change amount F (x1) calculated based on the fuel amount change amount F (x1) (X2)], and feedback control of the increase / decrease amount of the oxidizer determined according to the temperature set value tic_out is performed.

Further, in terms of flow rate of fuel in accordance with the increased weight of the oxidizer values [F (x1)], the [oxygen flow rate current value (Q _{o2 _ pv)} / theoretical amount of oxygen (A _o2) / excess air ratio (u)] + [the air flow rate current value (Q _{air _ pv)} / theoretical amount of air (a _o) / excess air ratio (u)] is, in terms of the oxidant flow rate in accordance with increased loss of the fuel value [F (x2)], the value [current fuel flow rate ( in that the _{gas _} Q _pv) × theoretical amount of air (a _o) × excess air ratio (u)] is characterized.

In addition, the oxidizer linkage control unit may include an air increase / decrease selection unit for converting the air flow rate conversion value [F (x3)] according to the increase / decrease amount of the oxidizer determined from the oxidizer increase / decrease selection unit and the oxygen flow rate setting value, An air flow rate indication regulating unit for regulating an air flow rate supplied from the air supply line to the burner in accordance with the amount of increase / decrease of the air determined by the air flow rate selector, An oxygen concentration increasing / decreasing unit for changing the oxygen concentration of the combustion chamber to an oxygen flow rate [F (x4)] according to a set value to determine an increase / decrease amount of oxygen; And an oxygen flow rate indication adjusting unit for adjusting an oxygen flow rate to be supplied to the combustion chamber, And the oxygen increase / decrease selection unit receives a signal for the oxygen amount conversion value F (x6) of the air supplied to the burner by receiving a signal for the conversion value F (x5) And feedback control of the increase / decrease amount of oxygen is received.

Further, in terms of air flow rate according to increase weight and the oxygen flow rate set point of the oxidizer values [F (x3)] is, [the temperature set value (tic_out) × fuel flow rate maximum value (Q _{gas _ max)} - oxygen flow rate set point (Q _{o2 _ sv)} / theoretical amount of oxygen (a _o2) / excess air ratio (u)] × theoretical amount of air (a _o) × excess air ratio (u) is, in terms of the oxygen flow rate according to the increased weight and the oxygen flow rate set point of the oxidizer values [F (x4 ), the temperature set value (tic_out) × fuel flow rate maximum value (Q _{gas _ max)} × oxygen flow rate set point (Q _{o2 _ sv)} × theoretical amount of oxygen (a _o2) × excess air ratio (u), and supplied to the combustion chamber in terms of amount of air of the oxygen values [F (x5)] is, [the fuel flow rate of the current value (Q _{gas _ pv)} - oxygen flow rate current value (Q _{o2 _ pv)} / theoretical amount of oxygen (a _o2) / excess air ratio (u)] × theoretical amount of air (a _o) × excess air ratio (u) is, in terms of oxygen content of air supplied to the burner values [F (x6)] is, [the fuel flow rate of the current value (Q _{gas _ pv)} - air flow rate current value ( Q _{air _ pv)} / theoretical amount of air (A _o) / surplus Air ratio (u)] × theoretical oxygen amount (A _o2 ) × excess air ratio (u).

The apparatus for controlling combustion of oxygen lancing in a heating furnace according to the present invention differs from that of the prior art in that the emission of NO _x is increased due to an increase in nitrogen (N ₂ ) in the air, which is a single oxidizing agent, So that the generation of NO _x can be reduced.

Particularly, when oxygen, which is an oxidant, is supplied separately from air, oxygen is directly supplied into the combustion chamber of the heating furnace without supplying oxygen through the burner, whereby the complete combustion of the fuel can be efficiently achieved, Can be saved.

On the other hand, it is possible to optimally feedback control of the amount of fuel, air, and oxygen supplied through a triple-cross control which can automatically control the flow rate of supplied fuel, air and oxygen.

1 is a schematic view showing a combustion control apparatus for a heating furnace according to the prior art,
FIG. 2 is a block diagram showing the combustion control process of the embodiment of FIG. 1,
3 is a schematic view showing an oxygen lancing combustion control apparatus in a heating furnace according to the present invention,
4 is a block diagram illustrating a combustion control process of the embodiment of FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Hereinafter, a preferred embodiment of an oxygen lancing combustion control apparatus for a furnace according to the present invention will be described in detail with reference to the accompanying drawings.

3 and 4, the apparatus for controlling combustion of oxygen in a heating furnace according to the present invention includes a heating furnace 10, a burner 20, a fuel supply line 30, an air supply line 40, (50) and a combustion control unit (60). The combustion control unit 60 includes a temperature indication control unit 100, a fuel increase / decrease selection unit 200, a fuel flow rate indication control unit 300, an oxidizer increase / decrease selection unit 400, The oxygen concentration controller 500 includes an air intensity selector 510, an air flow rate indicator 520, an oxygen concentration selector 530, and an oxygen flow rate controller 540.

First, as shown in FIG. 3, the apparatus for controlling combustion of oxygen in the heating furnace according to the present invention is provided with a heating furnace 10 in which a heating material (not shown) is accommodated in an internal combustion chamber 11. The heating material accommodated in the combustion chamber 11 of the heating furnace 10 enters the combustion chamber 11 of the heating furnace 10 so as to be rolled in a post-process as a slab, bloom, billet or the like. In the case of the heating furnace 10, usually, it can be made of a preheating zone, a heating zone, and a crack, and each of them is set to the atmosphere temperature inside the combustion chamber 11 in consideration of the extraction target temperature and the residence time of the heating material.

The burner 20 is installed in the heating furnace 10 as shown in FIG. 3, and receives fuel and air, and burns the combustion chamber 11 of the heating furnace 10. The burning of the fuel by the burner 20 causes a flame and the heating material contained in the combustion chamber 11 of the heating furnace 10 is heated. A fuel supply line 30 and an air supply line 40 are installed so that fuel and air are supplied to the burner 20.

That is, as shown in FIG. 3, the fuel supply line 30 supplies fuel to the burner 20, and the air supply line 40 supplies air to the burner 20. A valve (not shown) is provided to adjust the flow rate of fuel and air supplied to the burner 20 through the fuel supply line 30 and the air supply line 40. This valve And the flow rate of air are controlled.

The above-described heating furnace 10, the burner 20, the fuel supply line 30 and the air supply line 40 are the same as the conventional combustion furnace combustion control apparatus in the conventional heating furnace, Control is widely known. In the present invention, pure oxygen is separately supplied together with air as an oxidant for fuel combustion, and a triple-cross control in which a combustion control unit 60, which will be described later, controls the air and oxygen in conjunction with the flow rate of fuel. Accordingly, it is possible to reduce the generation of NO _x by separately supplying oxygen together with air, which is an oxidant of the fuel to be injected, as compared with the conventional increase of NO _{x in} the air due to an increase in nitrogen (N ₂ ) will be.

3, the oxygen supply line 50 directly supplies oxygen into the combustion chamber 11 of the heating furnace 10. The oxygen supply line 50 is provided separately from the oxygen supply line 50 as shown in FIG. The oxygen supply line 50 directly supplies oxygen into the combustion chamber 11 of the heating furnace 10 as the air supply line 40 supplies air to the burner 20, And the like of the oxygen to be injected into the combustion chamber 11 of the combustion chamber 11 can be appropriately controlled to prevent the rise of the NOx expected by direct injection into the flame of the burner 20, Thereby improving the thermal cycling. The effect of this is that by replacing a part of the supplied air with oxygen, the nitrogen (N ₂ ) ratio of the oxidizing agent can be lowered and the efficiency of combustion can be increased. That is, by injecting oxygen, which is an oxidant, in addition to air, combustion efficiency is prevented from being lowered due to nitrogen (N ₂ ) in the air, so that a fuel saving effect is obtained. By the increase of the overall radiation efficiency in the combustion chamber 11, The productivity can be improved.

3, the combustion control unit 60 is connected to the fuel supply line 30, the air supply line 40, and the oxygen supply line 50, respectively, in accordance with the supply of fuel, air, Air and oxygen supplied to the combustion chamber 11 of the burner 20 and the heating furnace 10 so as to reach the target temperature to be converted by receiving the ambient temperature inside the combustion chamber 11, Respectively. A temperature sensor for sensing the temperature of the combustion chamber 11 of the heating furnace 10 is naturally included in the combustion control unit 60 so as to receive the ambient temperature inside the combustion chamber 11, A flow control valve (not shown) is provided on the supply line 30, the air supply line 40 and the oxygen supply line 50 to control the burner 20 and the heating furnace 10 under the control of the combustion control unit 60. [ The flow rate of the fuel, air, and oxygen supplied to the combustion chamber 11 of the engine 10 will be controlled.

Referring to FIG. 4, the combustion control unit 60 includes a temperature indication control unit 100, a fuel increase / decrease selection unit 200, a fuel control unit A flow rate indication regulator 300, an oxidizer increase / decrease selector 400, and an oxidizer linkage regulator 500.

The temperature indicating control unit 100 is a so-called TIC (Temperature Indicator Control), and receives the ambient temperature of the combustion chamber 11, compares it with the target temperature, and outputs a temperature setting value tic_out. The temperature indication control unit 100 not only receives and directs the ambient temperature of the combustion chamber 11 as it is named but also sets the target temperature to be converted and compares the received ambient temperature with the target temperature to obtain the temperature set value tic- . The temperature set value tic_out is a difference value between the atmospheric temperature and the target temperature, and indicates the converted value of the combustion load in accordance with the temperature set value tic_out. For example, assuming that the ambient temperature is 500 and the target temperature is 510, the difference value is +10. The temperature set value tic_out output here is not merely the temperature difference +10 but represents the conversion value of the combustion load for raising the temperature from 500 to 500 to the target temperature 510. Of course, the temperature setting value tic_out output from the temperature instruction adjusting unit 100 may be simply changed to the temperature difference + 10, and the temperature setting value tic_out may be converted into another conversion value according to the function receiving unit.

The fuel change selector 200 receives the temperature set value tic_out from the temperature instruction adjuster 100 and determines the amount of increase / decrease of the fuel. That is, when receiving the temperature set value tic_out which is +10, which is the difference value between the ambient temperature 500 and the target temperature 510, it is determined that the fuel supply should be further increased (+), To determine how much more to increase.

The fuel flow rate control unit 300 is called FFIC (Fuel Flow Indicator control) and is supplied from the fuel supply line 30 to the burner 20 in accordance with the amount of increase / decrease of the fuel determined from the fuel select / Thereby adjusting the fuel flow rate. The fuel flow rate control unit 300 functions as a flow control valve, and indicates how much the current flow rate of the fuel is supplied to the burner 20.

The fuel is supplied to the burner 20 through the fuel increase / decrease selection unit 200 and the fuel flow rate control unit 300, and at the same time, the oxidant is supplied for burning the fuel. To this end, an oxidizer increase / decrease selection unit 400 and an oxidizer linkage adjustment unit 500 are provided.

The oxidizer increase / decrease selector 400 receives the temperature set value tic_out from the temperature instruction adjuster 100 and determines the increase / decrease amount of the oxidizer. That is, the amount of oxidizing agent required for complete combustion is determined according to the increase / decrease of the fuel determined by the fuel increase / decrease selector 200 described above.

The oxidizer linkage controller 500 correlates the air and oxygen flow rates according to the amount of oxidizer increase / decrease determined by the oxidizer increase / decrease selector 400 and the oxygen flow rate set value. The air and the oxygen are supplied together with the oxidizing agent of the fuel which burns the inside of the combustion chamber 11 of the heating furnace 10 so that the flow rates of air and oxygen which are the oxidizing agents are coordinated and controlled. At this time, the oxygen flow rate setting value (Qair_sv) is set in advance with the increase / decrease amount of the oxidizing agent. That is, dundamyeon oxygen flow rate set point (Q _{air _ sv)} as a 20% increase in the weight of the oxidizing agent, air flow rate will be 80%. That is, when the increase / decrease amount of the oxidizer is +10, the oxygen flow rate becomes +2 and the air flow rate becomes +8. However, the oxygen flow rate set point (Q _{air _ sv)} can change the oxygen flow rate set point (Q _{air _ sv)} for size and shape, or to maximize the combustion efficiency of the kind of the heating material and the heating (1).

4, the fuel increase / decrease selection unit 200 receives a signal corresponding to the fuel flow rate conversion value F (x1) according to the increase / decrease amount of the oxidizer and outputs the fuel flow rate conversion value F (x1) according to the temperature set value tic_out And the oxidizer increase / decrease selector 400 receives a signal for the oxidizer flow rate conversion value F (x2) according to the increase / decrease amount of the fuel, and outputs the oxidizer gas flow rate conversion value F (x2) to the temperature set value tic_out And feedback control of the increase / decrease amount of the oxidant determined accordingly. In other words, the fuel flow rate is determined by the fuel increase or decrease the selection unit 200, the fuel flow rate of the current value (Q _{gas _ pv)} the time to be supplied to the burner 20, the fuel flow rate of oxidant flow rate for the current value (Q _{gas_pv)} present value It is necessary to check whether it is supplied properly. Thus, in terms of the fuel flow rate according to the increase of the oxidant loss values [F (x1)] received signal to receive a fuel-sensitized selector 200 for the feedback control to the current fuel flow value (Q _{gas _ pv).} Further, when the determination is also an oxidizing agent flow oxidant decrease selecting section 400 to be supplied to the oxidizing agent flow rate present value, fuel flow check station whether the current value (Q _{gas _ pv)} is supplied properly for the oxidant flow rate current value to be supplied It is necessary to perform mutual feedback control accordingly.

Flow rate conversion value [F (x1)] of fuel in accordance with the increased weight of the oxidant, since the oxidizing agent is air and the two types of oxygen, [oxygen flow rate current value (Q _{o2 _ pv)} / theoretical amount of oxygen (A _o2) / excess the air ratio is a (u)] + [the current air flow rate value (Q _{air _ pv)} / theoretical amount of air (a _o) / excess air ratio (u)]. Further, the flow rate of the oxidizer in accordance with the increased loss of the fuel value in terms of [F (x2)] is, is the [current fuel flow value (Q _{gas _ pv)} × theoretical amount of air (A _o) × excess air ratio (u)].

4, the oxidizer linkage controller 500 includes an air flow rate selector 510, an air flow rate controller 520, an air flow rate selector 530, And a flow instruction regulating unit 540.

Air or decrease the selection unit 510 is increased in the air is converted into values [F (x3)] the air flow rate in terms of the increased weight of the oxidizing agent and the oxygen flow rate set point (Q _{air _ sv),} as determined from the oxidant or decrease selector 400 Decrease the weight. That is, the air flow rate conversion value [F (x3)] according to the increased weight and the oxygen flow rate set point of the oxidant, the Temperature Setting (tic_out) × fuel flow rate maximum value (Q _{gas _ max)} - oxygen flow rate set point (Q _{o2 _ sv} ) / theoretical oxygen amount (A _o2 ) / excess air ratio (u)] theoretical air amount (A _o ) x excess air ratio (u). The increase / decrease amount of the air determined by the air increase / decrease selector 510 is determined based on the increase / decrease amount of the oxidizer determined from the oxidizer increase / decrease selector 400, which receives the signal from the temperature instruction adjuster 100, the amount of the by subtracting the value for the _{air _ sv)} is the amount of increase or decrease in the air.

The air flow rate indication control unit 520 is an AFIC (Air Flow Indicator Controll) and is supplied from the air supply line 40 to the burner 20 in accordance with the increase / decrease amount of the air determined by the air flow rate selection unit 510 Adjust the air flow rate.

The oxygen decrease selecting section 530 oxygen in terms of the oxygen flow rate according to the increased weight of the oxidizing agent and the oxygen flow rate set point (Q _{air _ sv),} as determined from the oxidant or decrease selection unit 400 converts a value [F (x4)] Is determined. That is, in terms of the oxygen flow rate according to the increased weight and the oxygen flow rate set point of the oxidizer values [F (x4)] is, [the temperature set value (tic_out) × fuel flow rate maximum value (Q _{gas _ max)} × oxygen flow rate set point (Q _{o2 _ sv} ) × theoretical oxygen amount (A _o2 ) × excess air ratio (u)]. Therefore, the increase / decrease amount of oxygen determined by the oxygen increase / decrease selection unit 510 is determined based on the increase / decrease amount of the oxidizer determined from the oxidizer increase / decrease selection unit 400 that receives the signal from the temperature indication adjustment unit 100, (Q _{air sv _)} will be a value for.

The oxygen flow rate indication control unit 540 is an OFIC (O ₂ Flow Indicator Control) that controls the flow of oxygen from the oxygen supply line 50 to the combustion chamber 11 Adjust the supplied oxygen flow rate.

On the other hand, an oxidizing agent-sensitized selector increased weight and the oxygen flow rate set point (Q _{o2 _ sv)} of the oxidant, determined from 400 in accordance with the air-sensitized selection unit 510, the air flow rate current value and an oxygen sensitizer which is supplied is determined by the selection unit It is necessary to check whether or not the value of the oxygen flow rate current value determined and supplied by the oxygen sensor 530 matches the actual flow rate current value actually supplied, and it is necessary to perform feedback control in association with each other.

4, the air increase / decrease selection unit 510 receives a signal regarding the oxygen conversion amount F (x5) of oxygen supplied to the combustion chamber 11, And the oxygen up / down selector 530 receives a signal on the oxygen amount conversion value F (x6) of the air supplied to the burner 20, and feedback controls the increase / decrease amount of the oxygen.

That is, in terms of amount of air of the oxygen value to be supplied to the combustion chamber (11) [F (x5) ] is, [the fuel flow rate of the current value (Q _{gas _ pv)} - oxygen flow rate current value (Q _{o2 _ pv)} / theoretical amount of oxygen ( A _o2 ) / excess air ratio (u)] theoretical air amount (A _o ) x excess air ratio (u). Thus, the air-sensitized selecting unit 510 and the air flow rate determined in accordance with the increased weight of the oxidizing agent and the oxygen flow rate set point (Q _{o2 _ sv),} as determined from the oxidant or decrease selection unit 400, the actual fuel flow rate of the current value (Q _{gas _ pv} (Q _{air_pv} ) obtained by subtracting the value of the oxygen flow rate current value (Q _{o2_pv} ) from the current value of the oxidant flow rate through the air flow rate present value (Q _{air_pv} ).

Further also, in terms of the oxygen content of air supplied to the burner 20 values [F (x6)] is, [the fuel flow rate of the current value (Q _{gas _ pv)} - air flow rate current value (Q _{air _ pv)} / theoretical amount of air ( A _o2 ) / excess air ratio (u)] × theoretical oxygen amount (A _o ) × excess air ratio (u). Thus, the oxygen-sensitized selection unit 530, an oxygen flow rate determined in accordance with the increased weight and the oxygen flow rate set point (Q _{o2 _ sv)} of the oxidizing agent as determined from the oxidant or decrease selecting section 400 and the actual fuel flow rate of the current value (Q _{gas _ pv} (Q _{air_pv} ) obtained by subtracting the value of the air flow rate current value (Q _{o2_pv} ) from the current value of the oxidant flow rate through the air flow rate current value (Q _{air_pv} ).

As described above, the oxygen lancing combustion control apparatus of the heating furnace according to the present invention increases the NO _x emission due to the increase of nitrogen (N ₂ ) in the air, which is a single oxidizing agent, It is possible to separately supply oxygen to reduce the generation of NO _x .

Particularly, when oxygen, which is an oxidant, is supplied separately from air, oxygen is directly supplied into the combustion chamber 11 of the heating furnace 10 without supplying oxygen through the burner 20, thereby achieving efficient combustion of the fuel efficiently And the fuel can be saved by increasing the radiation efficiency.

On the other hand, it is possible to optimally feedback control of the amount of fuel, air, and oxygen supplied through a triple-cross control which can automatically control the flow rate of supplied fuel, air and oxygen.

The embodiments of the present invention described above and shown in the drawings should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of the present invention as long as they are obvious to those skilled in the art.

10: heating furnace 11: combustion chamber
20: Burner
30: fuel supply line
40: air supply line
50: oxygen supply line
60:
100:
200: fuel addition /
300: Fuel flow rate control unit
400: oxidizer increase / decrease selection unit
500: Oxidant coupling regulator
510: air increase / decrease selector 520: air flow rate controller
530: Oxygen up / down selector 540: Oxygen flow rate controller

Claims (5)

A burner which is installed in the heating furnace and is supplied with fuel and air and burns the combustion chamber into a combustion chamber of the heating furnace; a fuel supply line for supplying fuel to the burner; An air supply line for supplying air to the burner, an oxygen supply line for directly supplying oxygen into the combustion chamber of the heating furnace, and a fuel supply line, an air supply line and an oxygen supply line, And a combustion control unit for controlling the flow rates of air and oxygen, which are oxidants, respectively, supplied to the combustion chamber of the burner and the heating furnace so as to reach the target temperature to be converted by receiving the atmosphere temperature inside the chamber,
Wherein the combustion control unit includes:
A temperature indication adjusting unit for receiving the atmospheric temperature of the combustion chamber and comparing the atmospheric temperature with the target temperature to output a temperature set value tic_out;
A fuel increase / decrease selection unit for receiving the temperature set value tic_out from the temperature indicating control unit and determining the increase / decrease amount of the fuel;
A fuel flow rate indication regulating unit for regulating a fuel flow rate supplied from the fuel supply line to the burner in accordance with the increase / decrease amount of fuel determined from the fuel increase /
An oxidizer increase / decrease selector for receiving the temperature set value tic_out from the temperature instruction adjuster and determining the increase / decrease amount of the oxidizer,
And an oxidizer linkage controller for correlating and adjusting the air and oxygen flow rates according to the increase / decrease amount of the oxidizer determined by the oxidizer increase / decrease selector and the oxygen flow rate set value,
Wherein the fuel-
A feedback control of the fuel increase / decrease amount determined according to the temperature set value tic_out is received by receiving a signal for the fuel flow rate conversion value F (x1) according to the increase / decrease amount of the oxidizer,
The oxidizer increase /
Wherein the controller is configured to feedback-control the increase / decrease amount of the oxidizer determined according to the temperature set value tic_out by receiving a signal on the oxidant flow rate conversion value F (x2) according to the increase / decrease amount of the fuel. Combustion control device.
delete The method according to claim 1,
The fuel-converted value [F (x1)] of the fuel according to the amount of increase /
( _Air flow rate present value (Q _{o2_pv} ) / theoretical oxygen amount (A _o2 ) / excess air ratio (u)] + [air flow rate current (Q _{air_pv} ) / theoretical air flow (A _o ) / excess air ratio
The oxidant flow rate conversion value F (x2) according to the increase / decrease amount of the fuel is calculated as follows:
(Fuel gas flow rate value Q _{gas_pv} ) × theoretical air flow rate (A _o ) × excess air ratio (u)].
The method according to claim 1,
The oxidant-
And an air flow rate conversion value [F (x3)] according to an oxygen flow rate setting value determined by the oxidizer increasing / decreasing selection unit and an oxygen flow rate setting value,
An air flow rate indication adjusting unit for adjusting an air flow rate supplied from the air supply line to the burner according to the increase / decrease amount of the air determined by the air increase /
(X4)] according to the increase / decrease amount of the oxidizer determined by the oxidizer increase / decrease selection unit and the oxygen flow rate set value to determine the increase / decrease amount of oxygen;
And an oxygen flow rate indication regulator for regulating an oxygen flow rate supplied from the oxygen supply line to the combustion chamber according to the increase / decrease amount of oxygen determined from the oxygen increase / decrease selector,
The air-
And a feedback control unit for receiving feedback of the amount of oxygen supplied to the combustion chamber [F (x5)],
The oxygen-
Wherein the controller is configured to feedback-control the increase / decrease amount of oxygen by receiving a signal on the oxygen conversion value [F (x6)] of the air supplied to the burner.
5. The method of claim 4,
The air flow rate conversion value F (x3) corresponding to the increase / decrease amount of the oxidizing agent and the oxygen flow rate setting value,
- temperature setting value (tic_out) × fuel flow rate maximum value (Q _{gas _ max)} - oxygen flow rate set point (Q _{o2 _ sv)} / theoretical amount of oxygen (A _o2) / excess air ratio (u)] × theoretical amount of air (A _o) × excess Air ratio u,
The oxygen flow rate value [F (x4)] according to the increase / decrease amount of the oxidizing agent and the oxygen flow rate setting value,
And temperature set value (tic_out) × the maximum fuel flow rate (Q _{gas _ max)} × oxygen flow rate set point (Q _{o2 _ sv)} × theoretical amount of oxygen (A _o2) × excess air ratio (u),
The air volume conversion value F (x5) of oxygen supplied to the combustion chamber is expressed by the following equation
- the fuel flow rate current value (Q _{gas _ pv)} - oxygen flow rate current value (Q _{o2 _ pv)} / theoretical amount of oxygen (A _o2) / excess air ratio (u)] × theoretical amount of air (A _o) × excess air ratio (u) and ,
The oxygen conversion value [F (x6)] of the air supplied to the burner is expressed by the following equation
- the fuel flow rate current value (Q _{gas _ pv)} - air flow rate of the current value (Q _{air _ pv)} / theoretical amount of air (A _o) / excess air ratio (u)] × theoretical amount of oxygen (A _o2) × excess air ratio (u) of Wherein the oxygen combustion control means controls the combustion of the oxygen lance in the heating furnace.

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