KR101394113B1 - Operation Apparatus and Method for Oxy-PC Combustion System - Google Patents

Abstract

The present invention relates to an apparatus and a method for smoothly operating both an air mode operation and a pure oxygen mode operation of an Oxy-PC combustion system that burns pulverized coal to generate steam.
The present invention relates to a method and apparatus for supplying carbon dioxide and an oxidizer to a combustion furnace and burning the same, and a high-temperature gas generated during a combustion process passes through a superheater and a reheater to generate steam. The exhaust gas passes through a primary and a secondary gas heater, In the Oxy-PC combustion system in which the solid particles are separated while passing through the dust collector, and then the exhaust gas passes through the induction blower. In the Oxy-PC combustion system, (Oxygen-free mode operation) in which oxygen and exhaust gas are mixed with each other, or alternatively, oxygen and exhaust gas are mixed with an oxidizer at a high concentration and the oxidizer is replaced with air during operation .
According to the present invention, it is possible to operate the Oxy-PC combustion system by changing the air mode operation and the pure oxygen mode operation without stopping the system during operation. Further, in the air mode operation, by recycling a part of the exhaust gas by using the primary exhaust gas recirculation controller, it is possible to reduce the possibility of fire that occurs before the pulverized coal reaches the burner. Further, by recycling a part of the exhaust gas using the secondary exhaust gas recirculation amount regulator, it is possible to reduce nitrogen oxides generated during combustion in the combustion furnace. Also, in the pure oxygen mode operation, the desulfurization agent and the denitration agent, which are uniformly mixed through the common desulfurization denitrifier sprayer, are simultaneously injected into the combustion furnace, thereby simultaneously controlling the discharge concentration of sulfur oxides and nitrogen oxides. In addition, the stable combustion state can be maintained through the interlocking operation of the primary oxygen amount regulator and the pure oxygen regulator. In addition, it is possible to cope with changing operating conditions in real time through the linkage of the superheater monitor, the reheater monitor and the secondary exhaust gas recirculation controller. Also, by using the gas mixed with the pure oxygen supplied from the oxygen supplier and the exhaust gas recirculated as the oxidizing agent, the pulverized coal is burned to minimize the inclusion of substances other than the carbon dioxide contained in the exhaust gas, so that the high concentration of carbon dioxide can be easily It can be recovered.

Description

Technical Field [0001] The present invention relates to an Oxy-PC combustion system,

The present invention relates to an apparatus and a method for smoothly operating a pure oxygen-pulverized coal combustion system that burns pulverized coal to generate steam, that is, an air-mode operation and a pure oxygen mode operation of an oxy-PC (pulverized coal) will be. More particularly, the present invention relates to a method of controlling the temperature of a furnace by supplying and pulverizing fine coal and an oxidizing agent to a furnace and causing the high temperature gas generated during the combustion process to pass through the superheater and the reheater, (Air mode operation) using air as an oxidant in an Oxy-PC combustion system in which heat is transferred to a cold gas passing through a dust collector, solid particles are separated through a dust collector, (Oxygen-free mode operation) in which oxygen and a flue gas are mixed with a high concentration of oxygen as an oxidizing agent on the way, or alternatively, a high concentration of oxygen and flue gas is mixed with an oxidizing agent, And to an apparatus and method for performing the method.

In general, the techniques and methods for burning pulverized coal using air as an oxidizing agent are well known and commonly used. However, when the air is used as the oxidizing agent to burn the pulverized coal, the nitrogen component gas of about 79% contained in the air is also present in the exhaust gas after combustion, so that it is difficult to recover the carbon dioxide (CO ₂ ). When nitrogen gas is removed from the air to make high-concentration oxygen of at least 90% and used as an oxidizing agent to burn the pulverized coal, carbon dioxide, which is known as a global warming substance, is present in the exhaust gas, so that carbon dioxide can be recovered easily .

In the case of using air as the oxidizer for burning the pulverized coal, which is a conventional art, the system configuration is simple, and there is no need for a device or a method for recirculating a large amount of exhaust gas to mix high purity oxygen. Further, the flow of the exhaust gas flows in one direction without being constituted by circulating loops, so that the structure of the combustion system is simple and easy to operate.

However, since the conventional technology can not easily recover the carbon dioxide generated in the combustion process, it is necessary to use an oxy-PC combustion system in which oxygen of high purity is mixed with exhaust gas as an oxidizer for pulverized coal combustion.

The Oxy-PC combustion system uses air or high purity oxygen and flue gas as an oxidizer as needed, and it is necessary to realize stable interchange operation without stopping the operating system.

It is an object of the present invention to provide an Oxy-PC combustion system for easily recovering carbon dioxide, in which the system is not stopped during the air mode operation process when the pulverized coal is burned, A combustion system operating device capable of continuous operation by changing to air mode operation condition without stopping the system during operation of the system under the mode operation condition and continuously connecting air mode operation and pure oxygen mode operation under stable conditions And a method of operation.

Another object of the present invention is to provide a combustion system operating device and a driving method capable of reducing the possibility of fire occurring before the pulverized coal reaches the burner.

It is still another object of the present invention to provide a combustion system operating apparatus and an operating method capable of reducing nitrogen oxides generated during combustion.

It is still another object of the present invention to provide a combustion system operating device and a method of operating the same capable of simultaneously controlling the discharge concentration of nitrogen oxides and sulfur oxides.

It is still another object of the present invention to provide a combustion system operating apparatus and method that can maintain a stable combustion state and cope with operating conditions that change in real time.

It is another object of the present invention to provide a combustion system operating apparatus and a method for operating the combustion system capable of easily recovering a high concentration of carbon dioxide in a carbon dioxide separation and recovery apparatus by minimizing the inclusion of substances other than carbon dioxide contained in the exhaust gas.

In order to achieve the above object, the present invention provides a burner and a combustion furnace for burning pulverized coal; A superheater and a reheater for generating steam by using the heat of the flue gas generated in the combustion furnace; A heater for heating the gas supplied to the combustion furnace by using the heat of the exhaust gas passed through the superheater and the reheater; A chimney which discharges flue gas to the outside; A condenser for condensing water in the flue gas by lowering the temperature of the flue gas; A carbon dioxide separation and recovery unit for recovering carbon dioxide from the flue gas passed through the condenser; A primary flue gas recirculation line branching between the condenser and the carbon dioxide separation and recovery unit and connected to the combustion furnace; A secondary exhaust gas recirculation line branched from the heater and the condenser to the combustion furnace; And a desulfurization denitration agent supply unit for supplying a desulfurizing agent and a denitration agent to the combustion furnace.

The apparatus for operating a combustion system according to the present invention includes a dust collector for filtering particulate matter contained in an exhaust gas passed through a heater; An induction blower installed on the downstream side of the dust collector to induce a flow of the exhaust gas; And an exhaust gas component measuring device installed upstream or downstream of the dust collector for measuring concentrations of sulfur oxides (SO _x ), nitrogen oxides (NO _x ), oxygen (O ₂ ), and carbon monoxide (CO).

The combustion system operating apparatus according to the present invention further comprises a primary flue gas recirculation regulator and a secondary flue gas recirculation regulator provided at the inlet sides of the primary flue gas recirculation line and the secondary flue gas recirculation line, respectively, for regulating the amount of the recirculated flue gas As shown in FIG.

The combustion system operating apparatus according to the present invention may further include a stack discharge amount adjuster installed between the manned blower and the condenser to adjust the amount of exhaust gas discharged to the stack.

The combustion system operating apparatus according to the present invention includes a primary air supplier and a secondary air supplier connected to the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, respectively, to supply air; A primary blower and a secondary blower installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, respectively, to flow gas toward the combustion furnace; And a primary gas mixer and a secondary gas mixer respectively installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line and connected with the primary air supply and the secondary air supply to mix air and recirculated exhaust gas .

The combustion system operating apparatus according to the present invention may further include a primary gas amount regulator and a secondary gas amount regulator respectively installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line to measure and adjust the gas amount, respectively.

An apparatus for operating a combustion system according to the present invention includes an oxygen supplier for supplying pure oxygen to a combustion furnace; And an overall oxygen amount regulator for controlling the total amount of oxygen supplied from the oxygen feeder.

The combustion system operating apparatus according to the present invention further comprises a primary gas mixer and a secondary gas mixer installed respectively on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line and connected to the oxygen supplier to mix the gas and oxygen .

The combustion system operating apparatus according to the present invention further includes at least one device selected from a primary oxygen meter and a secondary oxygen meter installed downstream of the primary gas mixer and the secondary gas mixer to measure the oxygen concentration can do.

In the combustion system operating apparatus according to the present invention, the oxygen feed line from the oxygen feeder is first branched in the direction of the primary gas mixer and the direction of the secondary gas mixer, and then the primary gas mixer direction oxygen supply line is connected to the primary gas mixer direction and the burner direction Lt; / RTI >

The combustion system operating apparatus according to the present invention is provided with a net oxygen amount regulator installed in a burner direction oxygen supply line to regulate the amount of oxygen directly fed to a burner and a regulator provided in a primary gas mixer direction oxygen supply line to supply to a primary gas mixer A first oxygen regulator for regulating the amount of oxygen to be supplied.

The apparatus for operating a combustion system according to the present invention comprises: a pulverized coal supplier for supplying pulverized coal to a furnace; And a pulverized coal gas mixer installed on the primary exhaust gas recirculation line and connected to the pulverized coal feeder to mix gas and pulverized coal.

The apparatus for operating a combustion system according to the present invention is characterized in that the desulfurization denitrifying agent supplier comprises a desulfurizer reservoir for storing the desulfurizer; A denitrifying agent reservoir for storing the denitration agent; And a desulfurizer feed rate controller and a denitrifier feed rate controller that respectively regulate feed rates of the desulfurizer and the denitrate supplied from the desulfurizer storage tank and the denitrifying agent storage tank.

The apparatus for operating a combustion system according to the present invention comprises a desulfurization denitrifier sprayer for spraying a desulfurizing agent and a denitration agent to a combustion furnace; And a desulfurization denitration mixer provided upstream of the desulfurization denitration agent injector for mixing the desulfurizing agent and the denitration agent.

The combustion system operating apparatus according to the present invention may further include a superheater monitor and a reheater monitor for monitoring the steam state of the superheater and the reheater outlet, respectively.

In addition, the present invention provides an exhaust gas purifying apparatus, comprising: an exhaust gas discharge line which generates steam through a superheater and a reheater, and which is heat-exchanged with a gas supplied to a combustion furnace, A primary flue gas recirculation line branched from a first point of the flue gas discharge line and connected to the combustion furnace; A secondary flue gas recirculation line branched from the second point of the flue gas discharge line and connected to the combustion furnace; And a desulfurization denitrifying agent supply line to which a desulfurizing agent and a denitration agent are supplied to the combustion furnace, and a combustion system operating method using the same.

According to the combustion system operating method of the present invention, the sulfur oxide concentration measured by the flue gas concentration measuring device is compared with the set value, and then the supply amount of the desulfurizing agent is adjusted through the desulfurizer supply regulator. If the measured value is higher than the set value, If the measured value is lower than the set value, the supply amount of the desulfurizing agent can be reduced.

According to the combustion system operating method of the present invention, after the nitrogen oxide concentration measured by the flue gas concentration measuring device is compared with the set value, the denitration agent supply amount is adjusted through the denitrifier supply amount adjuster. If the measured value is higher than the set value, If the measured value is lower than the set value, the amount of the denitration agent supplied can be decreased.

According to the combustion system operating method of the present invention, the desulfurizing agent and the denitration agent are mixed in a desulfurization denitrifier mixer, and then injected into the combustion furnace through the desulfurization denitrifier sprayer to simultaneously adjust the discharge concentration of sulfur oxides and nitrogen oxides.

According to the combustion system operating method of the present invention, when the oxygen concentration measured by the flue gas concentration measuring device is compared with the set value, if the deviation occurs, the oxygen supply amount is adjusted through the entire oxygen amount regulator. If the measured value is higher than the set value, If the measured value is lower than the set value, the oxygen supply amount can be increased.

According to the combustion system operating method of the present invention, it is possible to control the oxygen flow rate supplied to the primary gas mixer through the primary oxygen regulator after comparing the oxygen concentration measured by the primary oxygen analyzer with the operation set value.

According to the combustion system operating method of the present invention, the oxygen concentration operation set value is linked to the carbon monoxide concentration set value. If the carbon monoxide concentration set value is higher than the measured value, the oxygen concentration operation set value is increased. The oxygen concentration operation set value can be decreased.

According to the combustion system operating method of the present invention, the oxygen concentration operation set value can be adjusted in the range of 9 to 21%.

According to the method of operating the combustion system of the present invention, the amount of oxygen directly supplied to the burner and the amount of oxygen supplied to the primary gas The amount of oxygen supplied to the mixer can be adjusted.

According to the present invention, it is possible to operate the Oxy-PC combustion system by changing the air mode operation and the pure oxygen mode operation without stopping the system during operation.

Further, in the air mode operation, by recycling a part of the exhaust gas by using the primary exhaust gas recirculation controller, it is possible to reduce the possibility of fire that occurs before the pulverized coal reaches the burner.

Further, by recycling a part of the exhaust gas using the secondary exhaust gas recirculation amount regulator, it is possible to reduce nitrogen oxides generated during combustion in the combustion furnace.

Also, in the pure oxygen mode operation, the desulfurization agent and the denitration agent, which are uniformly mixed through the common desulfurization denitrifier sprayer, are simultaneously injected into the combustion furnace, thereby simultaneously controlling the discharge concentration of sulfur oxides and nitrogen oxides.

In addition, the stable combustion state can be maintained through the interlocking operation of the primary oxygen amount regulator and the pure oxygen regulator.

In addition, it is possible to cope with changing operating conditions in real time through the linkage of the superheater monitor, the reheater monitor and the secondary exhaust gas recirculation controller.

Also, by using the gas mixed with the pure oxygen supplied from the oxygen supplier and the exhaust gas recirculated as the oxidizing agent, the pulverized coal is burned to minimize the inclusion of substances other than the carbon dioxide contained in the exhaust gas, so that the high concentration of carbon dioxide can be easily It can be recovered.

FIG. 1 shows a configuration of an Oxy-PC combustion system operating apparatus according to an embodiment of the present invention.
Fig. 2 shows the configuration of an Oxy-PC combustion system operating apparatus according to a preferred embodiment of the present invention.
3 is a graphical representation of a method of operating an Oxy-PC combustion system operating apparatus according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

FIG. 1 shows the construction of an Oxy-PC combustion system operating apparatus according to an embodiment of the present invention. The operating apparatus according to this embodiment includes basic devices of an Oxy-PC combustion system, The combustion furnace 20, the superheater 30, the reheater 40, the primary gas heater 50, the secondary gas heater 60, the dust collector 70, the induction blower 80, the stack 90, A condenser 100, a primary blower 110, a secondary blower 120, a primary air supplier 130, a secondary air supplier 140, a pulverized coal supplier 150, an oxygen supplier 160, A desulfurization agent storage tank 170, a desulfurization agent storage tank 180, a denitrifying agent storage tank 190, and a desulfurization denitration agent injector 200.

The burner (10) and the combustion furnace (20) constitute a boiler and burns the pulverized coal as a raw material to generate a high temperature combustion gas.

The superheater 30 and the reheater 40 are installed in series on the downstream side of the combustion furnace 20 and generate steam by using the heat of the high temperature combustion gas generated in the combustion process.

The primary gas heater 50 and the secondary gas heater 60 are installed in parallel on the downstream side of the reheater 40 and are connected to each other through heat exchange with the primary exhaust gas recirculation line and the secondary exhaust gas recycling line, Air and / or recirculated flue gas).

The dust collector 70 is installed on the downstream side of the gas heaters 50 and 60 to filter particulate matter contained in the exhaust gas.

The induction blower 80 is installed on the downstream side of the dust collector 70, and allows the exhaust gas to flow well.

The stack 90 is branched from the downstream side of the induction blower 80 and serves to discharge the exhaust gas to the outside air.

The condenser 100 is installed on the downstream side of the induction blower 80 and serves to condense and separate the moisture contained in the exhaust gas by lowering the temperature of the exhaust gas.

The carbon dioxide separation and recovery unit 170 is installed downstream of the condenser 100 and serves to separate and recover carbon dioxide from the flue gas from which moisture is separated and removed.

In order to recover carbon dioxide more easily, it is preferable to measure the concentration of sulfur oxides and nitrogen oxides in the exhaust gas, and to determine the concentration of the desulfurizing agent and the denitrating agent It is preferable to control the injection amount at the same time so as to operate in an optimal state. In addition, it is preferable to measure the concentration of oxygen and carbon monoxide, and appropriately adjust the amount of oxygen used and the distribution position to increase the purity of carbon dioxide contained in the exhaust gas.

Two independent exhaust gas recirculation lines for recycling the exhaust gas to the combustion furnace 20 are branched and installed on the exhaust gas discharge line extending from the combustion furnace 20 to the downstream side. Specifically, the condenser 100 and the carbon dioxide separation / And a secondary exhaust gas recirculation line branched from the induction blower 80 and the condenser 100 and connected to the combustion furnace 20 are provided.

The primary blower 110 and the secondary blower 120 are installed on the downstream side of the primary air supplier 130 and the secondary air supplier 140 respectively on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, Air or recirculated flue gas to the burner.

The primary air supplier 130 and the secondary air supplier 140 are connected to the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line respectively to supply air in the atmosphere to the exhaust gas recirculation line, To the blower 120 side.

The pulverized coal supply device 150 is connected to the primary exhaust gas recirculation line to supply pulverized coal, and the pulverized coal supplied is injected into the furnace 20 through the burner 10 by recirculated flue gas, air and / or oxygen.

The oxygen supplier 160 is connected to the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line and the burner 10 to supply pure oxygen.

The desulfurizer storage tank 180 and the denitrifying agent storage tank 190 serve to store the desulfurizing agent and denitrifying agent supplied to the combustion furnace 20, respectively.

The desulfurization denitrifying agent injector 200 is installed in the combustion furnace 20 and injects the desulfurizing agent and the denitrifying agent supplied from the desulfurizing agent storage tank 180 and the denitrifying agent storage tank 190 into the combustion furnace 20.

FIG. 2 is a view showing a configuration of an Oxy-PC combustion system operating apparatus according to a preferred embodiment of the present invention, and FIG. 3 is a graphical representation of an operating method of an Oxy-PC combustion system operating apparatus according to a preferred embodiment of the present invention , The operating device according to this embodiment includes additional devices that are additionally installed in the basic device of the Oxy-PC combustion system shown in FIG. 1, specifically a flue gas component meter 210, a secondary flue gas recirculation regulator A secondary gas mixer 250, a primary gas mixer 260, a primary gas mixer 270, a secondary gas mixer 280, a secondary gas mixer 260, A total oxygen amount regulator 290, a secondary gas mixer 300, a secondary oxygen meter 310, a net oxygen amount regulator 320, a primary oxygen amount regulator 330, a primary gas mixer 340, Oxygen meter 350, pulverized coal gas mixer 360, desulfurizer feed rate controller 370, denitrification agent May be made, including geupryang regulator 380, a desulfurization denitration the mixer 390, monitors superheater 400, reheater monitor 410. The

The exhaust gas component measuring instrument 210 is installed on the downstream side of the gas heaters 50 and 60 and measures concentrations of at least sulfur oxides, nitrogen oxides, oxygen, and carbon monoxide.

The secondary flue gas recirculation regulator 220 is installed at a branch point with the secondary flue gas recirculation line on the downstream side of the artificial blower 80 and allows the flue gas to flow toward the secondary blower 120 as required, The amount of exhaust gas recirculated to the recycle line can be adjusted.

The stack discharge amount adjuster 230 is provided at a branch point between the downstream side of the secondary flue gas recirculation controller 220 and the discharge line in the direction of the stack 90 and serves to regulate the flow of the flue gas toward the stack 90 That is, the amount of exhaust gas discharged into the stack 90 is controlled.

The primary exhaust gas recirculation regulator 240 is installed at a downstream point of the condenser 100 at a junction with the primary exhaust gas recirculation line and circulates the exhaust gas passing through the condenser 100 to the primary blower 110 , And the amount of exhaust gas recirculated to the primary exhaust gas recirculation line can be adjusted.

The secondary gas mixer 250 is installed on the secondary exhaust gas recirculation line and is connected to the secondary air supply 140 and serves to mix the air with the recirculated exhaust gas.

The primary gas mixer 260 is installed on the primary exhaust gas recirculation line and is connected to the primary air supplier 130 and serves to mix the air with the recycle flue gas.

The primary gas quantity regulator 270 is installed downstream of the primary blower 110 on the primary exhaust gas recirculation line and serves to measure and regulate the amount of air and / or recirculated exhaust gas.

The secondary gas quantity regulator 280 is installed downstream of the secondary blower 120 on the secondary exhaust gas recirculation line and serves to measure and regulate the amount of air and / or recycle flue gas.

The total oxygen amount regulator 290 is installed on the downstream side of the oxygen feeder 160 and serves to control the total amount of oxygen supplied from the oxygen feeder 160.

The oxygen feed line from the oxygen feeder 160 is first branched in the direction of the primary gas mixer 340 and in the direction of the secondary gas mixer 300 and then the primary gas mixer direction oxygen feed line is connected to the primary gas mixer 340, Direction and the burner 10 direction.

The secondary gas mixer 300 is installed on the secondary exhaust gas recirculation line, is connected to the oxygen supplier 160, and serves to uniformly mix air and / or recirculated exhaust gas with oxygen.

The secondary oxygen meter 310 is installed on the downstream side of the secondary gas mixer 300 on the secondary exhaust gas recirculation line, and serves to measure the oxygen concentration.

The pure oxygen regulator 320 is installed in the oxygen supply line in the direction of the burner 10 and serves to regulate the amount of oxygen directly supplied to the burner 10.

The primary oxygen amount adjuster 330 is installed upstream of the primary gas mixer 340 on the oxygen supply line in the direction of the primary gas mixer 340 and regulates the amount of oxygen supplied to the primary gas mixer 340 .

The primary gas mixer 340 is installed on the primary exhaust gas recirculation line and is connected to the primary oxygen regulator 330 and serves to uniformly mix the air and / or recycle flue-gas with oxygen.

The primary oxygen meter 350 is installed on the downstream side of the primary gas mixer 340 on the primary exhaust gas recirculation line and serves to measure the oxygen concentration.

The pulverized coal gas mixer 360 is installed at a branch point of the pulverized coal supply line and the primary exhaust gas recirculation line on the downstream side of the primary oxygen meter 350 and serves to uniformly mix air, recycle flue gas, and / or oxygen and pulverized coal .

The desulfurizer supply regulator 370 is installed downstream of the desulfurizer reservoir 180 and regulates the supply amount of the desulfurizer.

The denitration regulator 380 is installed downstream of the denitration agent reservoir 190 and regulates the amount of the denitration agent supplied.

The desulfurization denitration mixer 390 is installed at a point where the desulfurizing agent supply line and the denitration agent supply line are combined, and serves to uniformly mix the desulfurizing agent and the denitration agent.

The superheater monitor (400) is connected to the superheater (30) and monitors the state of the outlet of the superheater (30).

The reheater monitor 410 is connected to the reheater 40 and monitors the steam condition at the reheater 40 outlet.

The present invention is adapted to use an apparatus and a method for regulating the amount of exhaust gas to be recirculated to monitor and control the state of the superheater 30 and the reheater 40.

Hereinafter, a method of operating the operating device according to the present invention will be described in detail.

In the present invention, the air mode operation burns pulverized coal with only air entering through the primary air supplier 130 and the secondary air supplier 140 as oxidizing agents. The exhaust gas is passed through the dust collector 70 and the artificial air blower 80, And is sent to the stack 90 to be discharged to the atmosphere. Further, when it is desired to reduce the fire that occurs before the pulverized coal reaches the burner 10 in the air mode operation, a part of the exhaust gas is recycled by using the primary exhaust gas recirculation amount controller 240. When the amount of nitrogen oxides generated in the combustion furnace 20 is to be reduced, a part of the exhaust gas can be recycled by using the secondary exhaust gas recirculation regulator 220.

In the pure oxygen mode operation, pulverized coal is combusted using a gas obtained by mixing pure oxygen supplied from the oxygen supplier 160 and exhaust gas recirculated as an oxidizer. The exhaust gas is supplied to the secondary exhaust gas recirculation regulator 220 and the primary exhaust gas recirculation A part of the carbon dioxide is recycled in the amount regulator 240 and the rest is sent to the carbon dioxide separation and collection unit 170 to separate and recover the carbon dioxide contained in the exhaust gas.

The net oxygen mode operation method, which is a main concern of the present invention, will be described in more detail as follows.

The sulfur oxide concentration measured by the flue gas concentration meter 210 is compared with the set value to adjust the desulfurizer supply adjuster 370. If the measured value is higher than the set value, the desulfurizer supply is increased. If the measured value is lower than the set value Reduce the supply of desulfurizer.

The nitrogen oxide concentration measured by the flue gas concentration meter 210 is compared with the set value to control the denitrifier supply adjuster 380. If the measured value is higher than the set value, the denitrifier supply is increased, If it is low, it reduces the amount of denitration agent supplied.

The supplied desulfurizing agent and denitrifying agent are uniformly mixed in a desulfurization denitrifier mixer 390 and then injected into the furnace 20 through the desulfurization denitrifier sprayer 200 to simultaneously control the discharge concentrations of sulfur oxides and nitrogen oxides .

When the oxygen concentration measured by the flue gas concentration meter 210 is compared with a predetermined oxygen concentration value and a deviation occurs, a signal is sent to the total oxygen concentration regulator 290 to adjust the oxygen supply amount. If the measured value is higher than the set value, And if the measured value is lower than the set value, the oxygen supply amount is increased.

The oxygen concentration measured by the primary oxygen meter 350 installed on the downstream side of the primary gas mixer 340 is compared with the operation set value (reference is 15%), and the oxygen flow rate supplied to the primary gas mixer 340 is set to 1 And adjusted by the tea oxygen regulator 330. The operation set value (15%) changes according to the carbon monoxide concentration set value measured by the flue gas component measuring device 210. If the carbon monoxide set value is higher than the measured value, the oxygen concentration operation set value is increased to 15% Is less than the measured value, the oxygen concentration operation set value is decreased by less than 15%. However, the maximum value should be 21% (15% + 6%) and the minimum value should be in the range of 9% (15% -6%).

The oxygen flow rates of the oxygen amount adjuster 320 and the first oxygen amount adjuster 330 are the same and are interlocked with each other based on the oxygen concentration measured by the first oxygen meter 350 and the operating preset value of 15%. When the oxygen flow rate of the first oxygen amount controller 330 is increased, the oxygen flow rate of the net oxygen amount controller 320 is decreased. On the other hand, the oxygen amount of the first oxygen amount controller 330 When the flow rate is decreased, the oxygen flow rate of the net oxygen amount controller 320 is increased. Therefore, the sum of the oxygen flow rates of the pure oxygen regulator 320 and the primary oxygen regulator 330 is the same.

According to the present invention, the air mode operation and the pure oxygen mode operation can be freely performed as required even during continuous operation without varying or stopping the output of the system, thereby maximizing the system utilization rate. That is, when it is desired to recover the carbon dioxide contained in the combustion gas generated during the combustion in the combustion furnace, it is necessary to operate in the pure oxygen mode to recover the carbon dioxide, and there is no need to recover the carbon dioxide contained in the combustion gas, If you can not recover carbon dioxide, you can operate in air mode. In this manner, the air mode operation and the pure oxygen mode operation are facilitated according to need, so that the combustion system can be continuously operated without output fluctuation or system stoppage.

10: Burner
20: Combustion furnace
30: Superheater
40: Reheating
50: Primary gas heater
60: Secondary gas heater
70: Dust collector
80: Manned blower
90: Stacking
100: condenser
110: Primary blower
120: Secondary blower
130: primary air supply
140: Secondary air supply
150: Pulverized coal feeder
160: oxygen supplier
170: Carbon dioxide separation and recovery machine
180: Desulfurizer storage tank
190: denitrification tank
200: Desulfurization denitration sprayer
210: Flue gas component measuring instrument
220: Secondary flue gas recirculation regulator
230: Stack discharge regulator
240: Primary flue gas recirculation regulator
250: Secondary gas mixer
260: Primary gas mixer
270: Primary gas quantity regulator
280: Secondary gas quantity regulator
290: Total oxygen regulator
300: Secondary gas mixer
310: Secondary oxygen meter
320: Nitrogen regulator
330: Primary oxygen regulator
340: Primary gas mixer
350: Primary oxygen meter
360: Pulverized coal gas mixer
370: Desulfurizer feed regulator
380: Demineralizer feed regulator
390: Desulfurization denitrification mixer
400: superheater monitor
410: reheat monitor

Claims (24)

A burner and a combustion furnace for burning the pulverized coal;
A superheater and a reheater for generating steam by using the heat of the flue gas generated in the combustion furnace;
A heater for heating the gas supplied to the combustion furnace by using the heat of the exhaust gas passed through the superheater and the reheater;
A chimney which discharges flue gas to the outside;
A condenser for condensing water in the flue gas by lowering the temperature of the flue gas;
A carbon dioxide separation and recovery unit for recovering carbon dioxide from the flue gas passed through the condenser;
A primary flue gas recirculation line branching between the condenser and the carbon dioxide separation and recovery unit and connected to the combustion furnace;
A secondary exhaust gas recirculation line branched from the heater and the condenser to the combustion furnace;
A desulfurization denitration agent supply unit for supplying a desulfurization agent and a denitration agent to the combustion furnace;
A primary air supply and a secondary air supply connected to the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, respectively, for supplying air;
A primary blower and a secondary blower installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, respectively, to flow gas toward the combustion furnace;
A primary gas mixer and a secondary gas mixer respectively installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line and connected with the primary air supply and the secondary air supply to mix air and recirculated exhaust gas;
An oxygen supplier for supplying pure oxygen to the combustion furnace;
An overall oxygen amount regulator for controlling the total amount of oxygen supplied from the oxygen supplier;
A combustion system operating device including a primary gas mixer and a secondary gas mixer, each installed on a primary exhaust gas recirculation line and a secondary exhaust gas recirculation line and connected to an oxygen feeder to mix gas and oxygen.
The method according to claim 1,
A dust collector for filtering particulate matter contained in the exhaust gas passed through the heater;
An induction blower installed on the downstream side of the dust collector to induce a flow of the exhaust gas; And
Installed upstream or downstream of the dust collector sulfur oxides (SO _x), nitrogen oxides (NO _x), oxygen (O ₂₎ and a combustion system, operating unit, comprising a concentration of carbon monoxide (CO) in addition to the exhaust gas component meter for measuring.
The method according to claim 1,
A combustion system operating device additionally comprising a primary exhaust gas recirculation regulator and a secondary exhaust gas recirculation regulator, each of which is installed at the inlet side of the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line to regulate the amount of exhaust gas recirculated.
The method according to claim 1,
A combustion system operating device, further comprising a stack amount regulator for regulating the amount of exhaust gas discharged into the stack.
delete The method according to claim 1,
A combustion system operating device further comprising a primary gas quantity regulator and a secondary gas quantity regulator respectively installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line for respectively measuring and regulating the gas quantity.
delete delete The method according to claim 1,
A combustion system operating device further comprising a primary oxygen meter and a secondary oxygen meter installed downstream of the primary gas mixer and the secondary gas mixer for measuring the oxygen concentration.
The method according to claim 1,
Characterized in that the oxygen feed line from the oxygen feeder is first diverted in the direction of the primary gas mixer and in the direction of the secondary gas mixer and thereafter the primary gas mixer direction oxygen feed line is again branched in the primary gas mixer direction and in the burner direction System operating device.
11. The method of claim 10,
A first oxygen gas supply line for supplying oxygen to the first gas mixer and a second oxygen gas supply line for supplying oxygen to the first gas mixer; A combustion system operating device further comprising an oxygen regulator.
The method according to claim 1,
A pulverized coal supply device for supplying pulverized coal to a combustion furnace; And
Further comprising a pulverized coal gas mixer installed on the primary flue gas recirculation line and connected to the pulverized coal feeder to mix the gas and the pulverized coal.
The method according to claim 1,
The desulfurization denitration agent supply portion
A desulfurizer reservoir for storing the desulfurizer;
A denitrifying agent reservoir for storing the denitration agent; And
A desulfurizing agent supply regulator for regulating the supply amount of the desulfurizing agent and the denitrating agent supplied from the desulfurizing agent storage tank and the denitration agent storage tank;
14. The method of claim 13,
A desulfurization denitration agent injector for injecting the desulfurizing agent and the denitration agent into the combustion furnace; And
And a desulfurization denitration agent mixer provided upstream of the desulfurization denitration agent injector for mixing the desulfurizing agent and the denitration agent.
The method according to claim 1,
A combustion system operating device further comprising a superheater monitor and a reheater monitor for monitoring the steam condition of the superheater and the reheating outlet, respectively.
An exhaust gas discharge line that generates steam through the superheater and the reheater and generates heat after being exchanged with the gas supplied to the combustion furnace;
A primary flue gas recirculation line branched from a first point of the flue gas discharge line and connected to the combustion furnace;
A secondary flue gas recirculation line branched from the second point of the flue gas discharge line and connected to the combustion furnace;
A desulfurization denitrifying agent supply line through which a desulfurizing agent and a denitration agent are supplied to the combustion furnace;
A primary air supply and a secondary air supply connected to the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, respectively, for supplying air;
A primary blower and a secondary blower installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line, respectively, to flow gas toward the combustion furnace;
A primary gas mixer and a secondary gas mixer respectively installed on the primary exhaust gas recirculation line and the secondary exhaust gas recirculation line and connected with the primary air supply and the secondary air supply to mix air and recirculated exhaust gas;
An oxygen supplier for supplying pure oxygen to the combustion furnace;
An overall oxygen amount regulator for controlling the total amount of oxygen supplied from the oxygen supplier;
A combustion system comprising a primary gas mixer and a secondary gas mixer, each installed on a primary exhaust gas recirculation line and a secondary exhaust gas recirculation line and connected to an oxygen feeder to mix gas and oxygen.
17. The method of claim 16,
The concentration of sulfur oxides in the flue gas is measured and compared with the set value. Then, the supply of desulfurizing agent is controlled. If the measured value is higher than the set value, the supply amount of the desulfurizing agent is increased. If the measured value is lower than the set value, .
17. The method of claim 16,
If the measured value is higher than the set value, the supply amount of the denitration agent is increased. If the measured value is lower than the set value, the denitration agent supply amount is decreased And the combustion system.
17. The method of claim 16,
A desulfurizing agent and a denitrating agent are mixed and then injected into the combustion furnace to simultaneously adjust the discharge concentration of sulfur oxides and nitrogen oxides.
17. The method of claim 16,
When oxygen concentration is measured in the flue gas component and the deviation is generated, the oxygen supply amount is adjusted. If the measured value is higher than the set value, the oxygen supply amount is decreased. If the measured value is lower than the set value, And the combustion system.
17. The method of claim 16,
Wherein the oxygen concentration supplied to the combustion furnace is measured and compared with the operation set value, and then the oxygen flow rate supplied to the combustion furnace is controlled.
22. The method of claim 21,
The oxygen concentration operation set value is linked to the carbon monoxide concentration set value. If the carbon monoxide concentration set value is higher than the measured value, the oxygen concentration operation set value is increased. If the carbon monoxide concentration set value is lower than the measured value, And the combustion system.
23. The method of claim 22,
And the oxygen concentration operation set value is adjusted in the range of 9 to 21%.
17. The method of claim 16,
Wherein the amount of oxygen directly supplied to the combustion furnace and the amount of oxygen mixed with the exhaust gas are controlled based on the oxygen concentration and the operation set value supplied to the combustion furnace.

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