KR20230153182A - Burner for mixed combustion of ammonia and coal, and a high-temperature low-oxygen gas supply system applied thereto - Google Patents

Abstract

The present invention premixes ammonia and high-temperature, low-oxygen gas inside the boiler of a thermal power plant and sprays them on the fuel-rich portion of the burner, while simultaneously supplying high-temperature, low-oxygen boundary gas to the interface between the coal, primary air, and ammonia injection portion, thereby reducing the flame. A burner for mixed combustion of ammonia and coal is disclosed that can reduce the generation of nitrogen oxides by lowering the local peak temperature and maintain a stable flame by equalizing the temperature distribution of the flame.
The burner for the above-mentioned mixed combustion of ammonia and coal includes a coal burner nozzle installed to supply coal and primary air toward the inside of the furnace of the boiler; an ammonia burner nozzle installed to penetrate the coal burner nozzle and supply ammonia fuel gas toward the inside of the furnace; a boundary gas supply pipe installed to penetrate the coal burner nozzle while surrounding the outside of the ammonia burner nozzle and supplying a high-temperature, low-oxygen boundary gas toward the inside of the furnace; a premixing chamber formed between the ammonia burner nozzle and the boundary gas supply pipe; and a boundary gas flow control valve installed inside the boundary gas supply pipe to lower the peak temperature of the flame by adjusting the amount of boundary gas flowing from the premix chamber toward the inside of the furnace.

Description

Burner for mixed combustion of ammonia and coal, and a high-temperature low-oxygen gas supply system applied thereto}

The present invention relates to a burner for mixed combustion of ammonia and coal and a supply system for high-temperature low-oxygen gas applied thereto. More specifically, the present invention relates to a burner for fuel over-enrichment of the burner by premixing ammonia and high-temperature low-oxygen gas inside the boiler of a thermal power plant. By spraying above and simultaneously supplying high-temperature, low-oxygen boundary gas to the interface between coal, primary air, and ammonia injection area, it lowers the local peak temperature of the flame, reduces the generation of nitrogen oxides, and equalizes the temperature distribution of the flame. It relates to a burner for mixed combustion of ammonia and coal that can maintain a stable flame and a high-temperature, low-oxygen gas supply system applied thereto.

A mid- to long-term energy transition is required to reduce carbon dioxide emissions from thermal power plants. Among them, ammonia is emerging as a new energy source for power production because it is easier to transport and store than hydrogen and is competitive in terms of economic feasibility.

However, ammonia is more difficult to ignite than ordinary fuel and has a slower flame propagation and combustion speed, so advanced combustion technology is required.

In addition, because ammonia contains a large amount of nitrogen atoms, the increased nitrogen compared to existing power plant fuels can be dissociated at a relatively low temperature and easily converted into nitrogen oxides (NOx) by oxidizing radicals and intermediate products. Such emissions of nitrogen oxides (NOx) are not only a problem in themselves, but also cause significant environmental harm because they are related to the increase in fine dust emissions.

Currently, existing thermal power plants comply with environmental regulations by ultimately reducing nitrogen oxides (NOx) generated during the boiler combustion process through post-treatment using SCR.

However, if nitrogen oxides (NOx) generated in the boiler furnace of a thermal power plant increases significantly compared to the design level, it may be difficult to treat it with existing facilities alone. In addition, catalyst production costs, input energy, waste catalyst treatment, and ammonia costs for SCR are required, and various problems such as ammonia slip leakage from SCR facilities are emerging.

Accordingly, in order to commercialize mixed combustion of ammonia and coal, a technology is needed to minimize nitrogen oxides (NOx) generated from the burner itself and at the same time maintain a stable flame.

In other words, the idea of using ammonia as a fuel for power generation has emerged around the world recently, but since the combustion technology for mixing ammonia and coal is in its early stages, there are many difficulties in practical application, which is because ammonia is a common fuel. This is because it is difficult to ignite and has a very slow flame speed compared to fossil fuels, resulting in a slow combustion speed.

In addition, because ammonia contains a large amount of nitrogen atoms, it causes environmental pollution problems due to high emissions of nitrogen oxides (NOx).

As a result, there are many difficulties in commercializing combustion technology for power generation boilers for mixed combustion of ammonia and coal and nitrogen oxide (NOx) reduction technology, and to solve this problem, the increase in nitrogen oxide (NOx) emissions is required. Since it has to rely on post-processing methods using SCR, there are many practical problems, including economic burden.

(Public Patent) No. 10-2022-0023374

The technical problem to be solved by the present invention is to premix ammonia and high-temperature low-oxygen gas inside the boiler of a thermal power plant and spray it on the fuel-rich part of the burner, and at the same time, create a high-temperature low-oxygen boundary at the interface between coal, primary air, and ammonia injection area. (Boundary) A burner for mixed combustion of ammonia and coal that can maintain a stable flame by lowering the local peak temperature of the flame, reducing the generation of nitrogen oxides and leveling the temperature distribution of the flame by supplying gas, and high-temperature low-oxygen oxygen applied thereto. To provide a gas supply system.

A burner for mixed combustion of ammonia and coal according to an embodiment of the present invention to solve the above technical problem is a coal burner nozzle installed to supply coal and primary air toward the inside of the furnace of the boiler, and the coal burner An ammonia burner nozzle that is installed through the nozzle and supplies ammonia fuel gas toward the inside of the furnace. It is installed through the coal burner nozzle while covering the outside of the ammonia burner nozzle and supplies high-temperature, low-oxygen boundary gas toward the inside of the furnace. a boundary gas supply pipe that supplies a premixing chamber formed between the ammonia burner nozzle and the boundary gas supply pipe, and a boundary gas installed inside the boundary gas supply pipe and heading toward the inside of the furnace from the premixing chamber. It includes a boundary gas flow control valve that adjusts the inflow amount to lower the peak temperature of the flame, and the ammonia burner nozzle is formed to communicate with the premix chamber and receives boundary gas provided through the boundary gas supply pipe, It is preferable that a premixing port is provided to mix the supplied boundary gas with the ammonia fuel gas provided through the ammonia burner nozzle and supply it to the inside of the furnace.

In an embodiment of the present invention, the boundary gas flow control valve is preferably installed between the outer peripheral surface of the ammonia burner nozzle and the inner peripheral surface of the boundary gas supply pipe to enable communication with the premixing chamber.

In an embodiment of the present invention, a portion of the high-temperature, low-oxygen boundary gas supplied to the premixing chamber is mixed with ammonia fuel gas through the interior of the ammonia burner nozzle through the premixing port and enters the furnace. The remaining part of the high-temperature, low-oxygen boundary gas that is injected into the reduction zone located in the center and supplied to the premixing chamber is injected into the inner peripheral surface of the boundary gas supply pipe and the ammonia with the inflow amount controlled by the boundary gas flow control valve. It is preferably configured to be sprayed toward the interface between ammonia fuel gas, coal, and primary air inside the furnace via the space between the outer peripheral surfaces of the burner nozzles.

An embodiment of the present invention further includes an ammonia supply pipe for supplying ammonia fuel gas toward the inside of the ammonia burner nozzle, and an ammonia supply pipe for controlling the supply amount of ammonia fuel gas between the ammonia burner nozzle and the ammonia supply pipe. It is desirable to install a flow control valve.

The embodiment of the present invention further includes a flexible pipe connecting the ammonia burner nozzle and the ammonia supply pipe, and the ammonia flow control valve is preferably installed between the ammonia supply pipe and the flexible pipe.

An embodiment of the present invention further includes an ammonia burner nozzle position adjusting device installed to adjust the axial position of the ammonia burner nozzle, and the ammonia burner nozzle position adjusting device is located at the free end of the ammonia burner nozzle. It is preferable that the axial position of the burner nozzle tip be fine-tuned with respect to the inside of the furnace of the boiler.

An embodiment of the present invention further includes a high-temperature low-oxygen gas supply pipe for supplying high-temperature low-oxygen gas toward the inside of the boundary gas supply pipe, and a high-temperature low-oxygen gas is supplied between the high-temperature low-oxygen gas supply pipe and the boundary gas supply pipe. It is desirable to install a high-temperature, low-oxygen gas control valve to control the supply amount.

An embodiment of the present invention further includes a purge gas supply pipe for supplying a purge gas to the inside of the boundary gas supply pipe, and a purge gas valve for controlling the supply amount of the purge gas is installed in the purge gas supply pipe. desirable.

An embodiment of the present invention is a gas distributor installed in a branched manner to the exhaust system of the boiler to receive low-temperature low-oxygen exhaust gas, and a gas distributor installed to heat exchange the low-temperature hypoxic gas provided through the gas distributor with the high-temperature hypoxic gas of the boiler. It is preferable to further include a gas heat exchanger, and a high-temperature, low-oxygen gas pipe installed to supply the high-temperature, low-oxygen gas that has passed through the gas heat exchanger to the high-temperature, low-oxygen gas supply pipe.

An embodiment of the present invention further includes a low-temperature hypoxic gas pipe connecting the gas distributor and the gas heat exchanger to enable communication, and the low-temperature hypoxic gas pipe includes a gas distribution flow control valve for controlling the supply amount of the low-temperature hypoxic gas. It is desirable to have it installed.

An embodiment of the present invention further includes a bypass pipe that bypasses the gas heat exchanger from the low-temperature low-oxygen gas pipe, wherein the high-temperature low-oxygen gas is supplied to the high-temperature low-oxygen gas supply pipe through the high-temperature low-oxygen gas pipe in the bypass pipe. It is desirable to install a bypass flow control valve to control the temperature.

The high-temperature low-oxygen gas supply system according to an embodiment of the present invention includes a burner for mixed combustion of ammonia and coal, an ammonia flow transmitter for detecting and transmitting the flow rate information of ammonia provided through the ammonia supply pipe, and the coal burner nozzle. A coal flow rate and property information transmitter that detects and transmits the supply amount and property information of the coal, an exhaust gas analysis information transmitter installed in the exhaust system of the boiler that detects and transmits the temperature, flow rate, and chemical species information of the exhaust gas, and the gas A gas flow controller that regulates the supply amount of low-temperature hypoxic gas provided to the low-temperature hypoxic gas pipe based on operation control of the distribution flow control valve, and the high-temperature hypoxic gas pipe based on operation control of the bypass flow control valve. A bypass flow controller that regulates the temperature of the high-temperature low-oxygen gas provided through the high-temperature low-oxygen gas supply pipe through the boundary gas flow control valve, which is provided into the furnace through the boundary gas supply pipe based on the operation control of the boundary gas flow control valve. From a boundary gas flow controller that controls the supply amount of boundary gas, a nozzle tip position controller that adjusts the axial position of the ammonia burner nozzle tip based on operation control of the ammonia burner nozzle position adjusting device, and the ammonia flow transmitter. The gas flow rate based on the ammonia flow rate information transmitted, the supply amount and property information of coal transmitted from the coal flow rate and property information transmitter, and the temperature, flow rate, and chemical species information of the exhaust gas transmitted from the exhaust gas analysis information transmitter. It is preferable to include a controller, an operation control device that outputs a control signal for operation control to the bypass flow controller, a permanent boundary gas flow controller, and the nozzle tip position controller.

The burner for mixed combustion of ammonia and coal according to an embodiment of the present invention and the high-temperature low-oxygen gas supply system applied thereto premix ammonia and high-temperature low-oxygen gas inside the boiler of a thermal power plant and spray the fuel-rich portion of the burner. At the same time, high-temperature, low-oxygen boundary gas can be supplied to the interface between coal, primary air, and ammonia injection area, thereby lowering the local peak temperature of the flame, reducing the generation of nitrogen oxides, and leveling the temperature distribution of the flame, creating a stable flame. can be maintained.

That is, the embodiment of the present invention actively utilizes the characteristics of nitrogen oxides generated according to the equivalence ratio of the components of ammonia to premix high-temperature low-oxygen gas and ammonia and then inject them into the fuel-rich portion of the burner, and at the same time, coal-primary air By providing a configuration that supplies boundary gas to the interface between the ammonia injection site and the ammonia injection site, it is possible to achieve the effect of lowering the local peak temperature of the flame, reducing the amount of thermal nitrogen oxides generated, and leveling the temperature distribution.

In addition, the embodiment of the present invention can create a reducing area for the combustion area, thereby reducing the generation of nitrogen oxides and increasing nitrogen oxide reduction, ultimately providing the effect of reducing the total amount of nitrogen oxides generated. .

Figure 1 is a diagram schematically showing the equipment configuration of a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.
Figure 2 is a diagram schematically showing a system for supplying high-temperature, low-oxygen gas to a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.
Figure 3 is a schematic diagram illustrating the operation control of a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.
Figure 4 is a diagram showing simulation results for a power generation system applying a high-temperature, low-oxygen gas supply system applied to a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.
Figure 5 compares the concentration of nitrogen oxides (NOx) emitted after combustion in a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention and a conventional technology that does not apply mixed combustion of ammonia and coal. The results are shown.
Figure 6 shows the concentration of ammonia and coal particles contained in the combustion gas discharged after combustion in a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention and in the prior art without applying mixed combustion of ammonia and coal. The results of comparing the trajectory and char conversion, fuel gas temperature, velocity vector, and combustion gas streamline are shown.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached illustration drawings. In this process, the thickness of lines or sizes of components shown in the drawing may be exaggerated for clarity and convenience of explanation. In addition, the terms described below are terms defined in consideration of functions in the present invention, and may vary depending on the intention or custom of the user or operator. Therefore, definitions of these terms should be made based on the content throughout this specification. In addition, the examples below do not limit the scope of the present invention, but are merely illustrative of the elements presented in the claims of the present invention, and are included in the technical idea throughout the specification of the present invention and constitute the scope of the claims. Embodiments that include elements that can be replaced as equivalents may be included in the scope of the present invention.

Figure 1 is a diagram schematically showing the equipment configuration of a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.

Referring to FIG. 1, the equipment configuration of a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention is largely comprised of an ammonia mixed combustion system 100, a high-temperature low-oxygen gas system 200, and boundary gas flow rate. It can be divided into a control valve 300 and a purge gas system 400.

The ammonia mixed combustion system 100 and the high-temperature low-oxygen gas system 200 are a coal burner nozzle (20) installed to supply coal and primary air together toward the furnace interior (12) of the boiler (10) of a thermal power plant. ), an ammonia burner nozzle 150 installed to supply ammonia fuel gas toward the inside of the furnace 12 while penetrating the coal burner nozzle 20, and a form surrounding the outside of the ammonia burner nozzle 150. and a boundary gas supply pipe 240 installed to supply high-temperature, low-oxygen boundary gas toward the inside of the furnace 12 while penetrating the coal burner nozzle 20, the outer peripheral surface of the ammonia burner nozzle 150, and A premixing chamber 230 formed in the form of a space between the inner peripheral surfaces of the boundary gas supply pipe 240, and installed inside the boundary gas supply pipe 240 to flow from the premixing chamber 230 to the inside of the furnace. It is configured to include a boundary gas flow control valve 300 that lowers the peak temperature of the flame by controlling the inflow of the boundary gas toward (12).

In addition, the ammonia burner nozzle 150 is formed to be able to communicate with the premix chamber 230, receives boundary gas provided through the boundary gas supply pipe 240, and supplies the supplied boundary gas to the ammonia burner nozzle. A pre-mixing port 160 is provided to mix the ammonia fuel gas provided through 150 and supply it to the inside of the furnace 12.

The boundary gas flow control valve 300 is installed between the outer peripheral surface of the ammonia burner nozzle 150 and the inner peripheral surface of the boundary gas supply pipe 240 and is installed in a structure that allows communication with the premix chamber 230. do.

That is, a premix chamber 230 capable of communicating with the premix port 160 is provided between the outer peripheral surface of the ammonia burner nozzle 150 and the inner peripheral surface of the boundary gas supply pipe 240, and the boundary gas supply pipe ( 240) is provided with a boundary gas flow control valve 300 for controlling the inflow amount of boundary gas from the premixing chamber 230 toward the inside of the furnace 12.

Accordingly, a portion of the high-temperature, low-oxygen boundary gas supplied to the premix chamber 230 is mixed with ammonia fuel gas through the interior of the ammonia burner nozzle 150 through the premix port 160. The remaining part of the high-temperature, low-oxygen boundary gas that is injected into the reduction area located in the center of the furnace 12 and supplied to the premix chamber 230 is controlled by the boundary gas flow control valve 300 in the amount of inflow. In this state, it passes through the space between the inner circumferential surface of the boundary gas supply pipe 240 and the outer circumferential surface of the ammonia burner nozzle 150 toward the interface between the ammonia fuel gas, coal, and primary air in the furnace interior 12. It is sprayed.

In this way, ammonia is premixed with high-temperature low-oxygen gas, sprayed into the reduction area at the center of the existing burner, and burned together with the boundary gas, thereby lowering the local peak temperature of the flame and reducing the generation of thermal NOx. By reducing fuel NOx in the reducing area and increasing the reduction effect of NOx, it is possible to ultimately expect a reduction in total NOx, as well as maintaining flame stability. can be provided.

To elaborate, the auxiliary devices of the ammonia mixed combustion system 100 are installed through the central portion of the existing coal burner, and specifically, the central portion of the coal burner nozzle 20 where coal and primary air are supplied. The ammonia burner nozzle 150, which has a pipe-shaped structure, and the boundary gas supply pipe 240 are installed in a penetrating manner.

In this case, the ammonia burner nozzle tip 170, which will be described later and is located at the free end of the ammonia burner nozzle 150, is installed in a structure disposed toward the inside of the furnace 12.

The ammonia mixed combustion system 100 further includes an ammonia supply pipe 110 for supplying ammonia fuel gas toward the inside of the ammonia burner nozzle 150. At this time, an ammonia flow control valve 120 is installed between the ammonia burner nozzle 150 and the ammonia supply pipe 110 to control the supply amount of ammonia fuel gas.

The ammonia mixed combustion system 100 further includes a flexible pipe 130 connecting the ammonia burner nozzle 150 and the ammonia supply pipe 110. At this time, the ammonia flow control valve 120 is configured to be installed between the ammonia supply pipe 110 and the flexible pipe 130.

To elaborate, ammonia fuel gas can be supplied to the furnace interior 12 through the ammonia supply pipe 110, and at this time, the flow rate can be adjusted or the supply can be blocked through the ammonia flow control valve 120. . In addition, the ammonia supply pipe 110 uses a flexible pipe 130 to form a structure connected to the ammonia burner nozzle 150.

The ammonia mixed combustion system 100 further includes an ammonia burner nozzle position adjusting device 140 installed to adjust the axial position of the ammonia burner nozzle 150. At this time, the ammonia burner nozzle position adjusting device 140 adjusts the axial position of the ammonia burner nozzle tip 170 located at the free end of the ammonia burner nozzle 150 to the inside of the furnace 12 of the boiler 10. It is configured to fine tune.

For example, the ammonia burner nozzle position adjusting device 140 allows the axial position of the ammonia burner nozzle 150 toward the furnace interior 12 to be adjusted within an appropriate range, and the ammonia burner nozzle ( 150), and may be composed of a rack gear installed on the outer peripheral surface of the rack gear and a pinion gear that meshes with the rack gear and rotates by rotational force provided from the outside.

Accordingly, the present invention utilizes the ammonia burner nozzle position adjusting device 140 using a pinion gear and rack gear installed on the ammonia burner nozzle 150 to finely adjust the position of the ammonia burner nozzle tip 170. It can be tuned, and through this, optimal ignition and flame stability can be secured depending on fuel conditions and operating load.

The high-temperature low-oxygen gas system 200 further includes a high-temperature low-oxygen gas supply pipe 210 for supplying high-temperature low-oxygen gas toward the inside of the boundary gas supply pipe 240. At this time, a high-temperature low-oxygen gas control valve 220 is installed between the high-temperature low-oxygen gas supply pipe 210 and the boundary gas supply pipe 240 to control the supply amount of the high-temperature low-oxygen gas.

The purge gas system 400 includes a purge gas supply pipe 420 installed to supply purge gas to the premix chamber 230 located inside the boundary gas supply pipe 240, and the purge gas supply pipe ( It is configured to include a purge gas valve 410 installed to control the supply amount of purge gas provided through 420).

That is, the purge gas supply pipe 420 is installed to communicate with the boundary gas supply pipe 240, and the purge gas supply pipe 420 has a purge gas valve 410 for controlling the supply amount of the purge gas. It consists of an installed structure.

Accordingly, the burner for mixed combustion of ammonia and coal according to an embodiment of the present invention is operated with the purge gas valve 410 closed during normal operation. On the other hand, after stopping use of the burner, the ammonia remaining inside the burner is removed for safety, and if it is necessary to remove residues such as dust and sulfur in the high-temperature, low-oxygen gas supply system, the ammonia flow control valve is used. With (120) and the high-temperature low-oxygen gas control valve 220 completely closed, the purge gas valve 410 is opened to supply compressed air or nitrogen into the purge gas supply pipe 420 to remove remaining ammonia. It can be removed.

Figure 2 is a diagram schematically showing a system for supplying high-temperature, low-oxygen gas to a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.

Referring to FIG. 2, a system for supplying high-temperature, low-oxygen gas to a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention consists of a high-temperature, low-oxygen gas supply system 500.

The high-temperature hypoxic gas supply system 500 is installed in a branched manner with respect to the exhaust system of the boiler 10, and includes a gas distributor 510 that receives low-temperature hypoxic exhaust gas, and low-temperature hypoxic gas supplied through the gas distributor 510. A gas heat exchanger 540 installed adjacent to the exhaust system of the boiler 10 in order to heat exchange gas with the high-temperature low-oxygen gas of the boiler 10, and heat exchange is performed through the gas heat exchanger 540. It is configured to include a high-temperature low-oxygen gas pipe 550 installed to provide high-temperature low-oxygen gas back to the high-temperature low-oxygen gas supply pipe 210.

The high-temperature hypoxic gas supply system 500 further includes a low-temperature hypoxic gas pipe 530 that connects the gas distributor 510 and the gas heat exchanger 540 to enable communication. In this case, a gas distribution flow control valve 520 is installed in the low-temperature hypoxic gas pipe 530 to control the supply amount of the low-temperature hypoxic gas provided to the gas heat exchanger 540.

The high-temperature hypoxic gas supply system 500 further includes a bypass pipe 570 that bypasses the gas heat exchanger 540 from the low-temperature hypoxic gas pipe 530. In this case, the bypass pipe 570 has a bypass flow control valve 560 for controlling the temperature of the high-temperature low-oxygen gas provided to the high-temperature low-oxygen gas supply pipe 210 through the high-temperature low-oxygen gas pipe 550. ) is configured to be installed.

That is, the high-temperature low-oxygen gas supply system 500 is directed toward the desulfurizer 592 through the gas distributor 510 located downstream of the electrostatic precipitator 580 and the manned blower 590 installed in the power generation system exhaust gas system. Some of the low-temperature, low-oxygen gas discharged is taken out.

Subsequently, the low-temperature hypoxic gas taken out through the gas distributor 510 passes through the low-temperature hypoxic gas pipe 530 with the flow rate controlled by the gas distribution flow control valve 520 and the gas heat exchanger 540. ) is supplied.

Next, the low-temperature hypoxic gas provided to the gas heat exchanger 540 is converted into high-temperature hypoxic gas through heat exchange with the high-temperature hypoxic gas, and then through the high-temperature hypoxic gas pipe 550 through the high-temperature hypoxic gas supply pipe ( 210).

At this time, some of the low-temperature low-oxygen gas provided from the low-temperature low-oxygen gas pipe 530 to the gas heat exchanger 540 may be directly supplied to the high-temperature low-oxygen gas pipe 550 through the bypass pipe 570. , This is to control the temperature of the high-temperature low-oxygen gas provided through the high-temperature low-oxygen gas pipe 550 to an appropriate state through operation control of the bypass flow control valve 560.

To elaborate, some of the low-temperature low-oxygen gas treated as dust in the exhaust system of the boiler 10 is converted into high-temperature low-oxygen gas of the required temperature through the gas heat exchanger 540 and the bypass flow control valve 560. Since the high-temperature low-oxygen gas can be supplied to the inside of the furnace 12 through the supply pipe 210, the burner for mixed combustion of ammonia and coal according to an embodiment of the present invention can not only maintain a stable flame, but also produce ammonia. There is an advantage in terms of preventing various problems that may occur during the operation of the burner used as fuel.

Meanwhile, in FIG. 2, an unexplained reference numeral 180 denotes an ammonia supply tank 180, which corresponds to a pressure vessel that stores ammonia provided through the ammonia supply pipe 110 shown in FIG. 1.

In addition, the unexplained code 190 corresponds to a differentiator 190, which corresponds to equipment for supplying coal gas to the coal burner nozzle 20 shown in FIG. 1, and the unexplained code 192 corresponds to the coal burner nozzle 20 shown in FIG. ) corresponds to the primary air blower 192 that supplies primary air toward, and the unexplained symbol 194 refers to the secondary air blower 194 that supplies secondary air toward the coal burner nozzle 20 shown in FIG. ) corresponds to

Figure 3 is a schematic diagram illustrating the operation control of a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.

Referring to FIG. 3, the operation control device 600 for controlling the operation of a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention includes flow rate information of ammonia provided to the ammonia supply pipe 110. An ammonia flow rate transmitter 610 that detects and transmits, a coal flow rate and property information transmitter 620 that detects and transmits the supply amount and property information of the coal provided to the coal burner nozzle 20, and the exhaust of the boiler 10 An exhaust gas analysis information transmitter 630 installed in the system to detect and transmit the temperature, flow rate, and chemical species information of the exhaust gas, and the low-temperature hypoxic gas pipe ( The high-temperature hypoxic gas is supplied through the high-temperature hypoxic gas pipe 550 based on the operation control of the gas flow controller 640, which controls the supply amount of the low-temperature hypoxic gas provided by 530, and the bypass flow control valve 560. A bypass flow controller 650 that controls the temperature of the high-temperature low-oxygen gas provided through the supply pipe 210, and the boundary gas supply pipe 240 based on the operation control of the boundary gas flow control valve 300. The ammonia burner nozzle tip 170 based on the operation control of the boundary gas flow controller 660, which controls the supply amount of the boundary gas provided to the inside of the furnace 12, and the ammonia burner nozzle position adjusting device 140. ) and a nozzle tip position controller 670 that controls the axial position.

In this case, the operation control device 600 includes ammonia flow rate information transmitted from the ammonia flow rate transmitter 610, coal supply amount and property information transmitted from the coal flow rate and property information transmitter 620, and the exhaust gas. Based on the temperature, flow rate, and chemical species information of the exhaust gas transmitted from the analysis information transmitter 630, the gas flow controller 640, the bypass flow controller 650, the standby boundary gas flow controller 660, and the It is configured to output a control signal for operation control to the nozzle tip position controller 670.

That is, the operation control device 600 of the burner system for mixed combustion of ammonia and coal according to an embodiment of the present invention includes the flow rate information of ammonia detected from the ammonia flow rate transmitter 610, the coal flow rate and property information transmitter ( Compare and calculate the supply flow rate and property information of coal detected from 620) and the temperature, flow rate, and chemical species information for exhaust gas detected from the exhaust gas analysis information transmitter 630 with the stored information in the built-in database, respectively. After processing, the flow rate of the gas by the gas distribution flow control valve 520 is controlled through operation control of the gas flow rate controller 640, and the gas flow rate by the gas distribution flow control valve 520 is controlled through operation control of the bypass flow rate controller 650. By controlling the flow rate of the bypassed gas by adjusting the opening degree of the bypass flow control valve 560, the final temperature of the high-temperature low-oxygen gas supplied to the high-temperature low-oxygen gas supply pipe 210 is adjusted to an appropriate state.

In addition, the operation control device 600 adjusts the opening degree of the boundary gas flow control valve 300 through operation control of the boundary gas flow controller 660 to distribute the flow rate for the premixing gas and the boundary gas. takes control.

In addition, the operation control device 600 uses the stored information of the built-in database to derive the position of the ammonia burner nozzle 150 suitable for the current conditions, and if necessary according to the operator's final judgment, the nozzle tip position controller The position of the ammonia burner nozzle tip 170 is adjusted through operation control of 670.

Figure 4 is a diagram showing simulation results for a power generation system applying a high-temperature, low-oxygen gas supply system applied to a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention.

That is, referring to FIG. 4, as a result of Combustion and Heat & mass balance analysis for the high-temperature low-oxygen gas supply system applied to the burner for mixed combustion of ammonia and coal according to the embodiment of the present invention, it is found that it is engineeringly feasible and reasonable. You can confirm that it is configured.

Figure 5 compares the concentration of nitrogen oxides (NOx) emitted after combustion in a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention and a conventional technology that does not apply mixed combustion of ammonia and coal. The results are shown.

That is, referring to FIG. 5, in the burner for mixed combustion of ammonia and coal according to an embodiment of the present invention and the prior art that does not apply mixed combustion of ammonia and coal, nitrogen oxides (NOx) emitted after combustion Comparing the concentrations, the result of application to the embodiment of the present invention in which ammonia and coal were mixed combustion was found to have a relatively low concentration of nitrogen oxides (NOx) compared to the case where mixed combustion of ammonia and coal was not applied. Good effects can be confirmed.

Figure 6 shows the concentration of ammonia and coal particles contained in the combustion gas discharged after combustion in a burner for mixed combustion of ammonia and coal according to an embodiment of the present invention and in the prior art without applying mixed combustion of ammonia and coal. The results of comparing the trajectory and char conversion, fuel gas temperature, velocity vector, and combustion gas streamline are shown.

That is, referring to FIG. 6, in the burner for mixed combustion of ammonia and coal to which an embodiment of the present invention is applied, ammonia premixed with high-temperature low-oxygen gas is burned in a reducing atmosphere at the center of the burner, and accordingly, the coal It can be seen that it has a good effect on combustion and gas temperature distribution around the burner. In addition, a burner for mixed combustion of ammonia and coal using an embodiment of the present invention can reduce nitrogen oxides (NOx) contained in the exhaust gas discharged after combustion, and a stable combustion state can be expected. can be checked.

10-Boiler 12-Inside the furnace
20-Coal burner nozzle
100-Ammonia mixed combustion system
110-Ammonia supply piping 120-Ammonia flow control valve
130-Flexible piping 140-Ammonia burner nozzle position adjustment device
150-Ammonia burner nozzle 160-Premix port
170-Ammonia burner nozzle tip 180-Ammonia supply tank
190-differentiator 192-primary air blower
194-Secondary air blower
200 - High-temperature hypoxic gas system
210-High-temperature low-oxygen gas supply piping 220-High-temperature low-oxygen gas control valve
230-Premixing chamber 240-Boundary gas supply piping
300-Boundary gas flow control valve
400-Purge gas system
410-Purge gas valve 420-Purge gas supply piping
500-High-temperature low-oxygen gas supply system
510-Gas distributor 520-Gas distribution flow control valve
530-Low temperature low oxygen gas piping 540-Gas heat exchanger
550-High temperature low oxygen gas piping 560-Bypass flow control valve
570-Bypass piping 580-Electrostatic precipitator
590-Manned blower
600-Operation control device
610-Ammonia flow transmitter 620-Coal flow and property information transmitter
630-Exhaust gas analysis information transmitter 640-Gas flow controller
650-Bypass flow controller 660-Boundary gas flow controller
670-Nozzle tip position controller

Claims (12)

A coal burner nozzle installed to supply coal and primary air toward the inside of the boiler's furnace;
an ammonia burner nozzle installed to penetrate the coal burner nozzle and supply ammonia fuel gas toward the inside of the furnace;
a boundary gas supply pipe installed to penetrate the coal burner nozzle while surrounding the outside of the ammonia burner nozzle and supplying a high-temperature, low-oxygen boundary gas toward the inside of the furnace;
a premixing chamber formed between the ammonia burner nozzle and the boundary gas supply pipe; and
It includes a boundary gas flow control valve installed inside the boundary gas supply pipe to lower the peak temperature of the flame by controlling the amount of boundary gas flowing from the premix chamber toward the inside of the furnace,
The ammonia burner nozzle is formed to be able to communicate with the premixing chamber, receives boundary gas provided through the boundary gas supply pipe, and mixes the supplied boundary gas with ammonia fuel gas provided through the ammonia burner nozzle. A burner for mixed combustion of ammonia and coal equipped with a premixing port supplied inside the furnace. In claim 1,
The boundary gas flow control valve is installed between the outer peripheral surface of the ammonia burner nozzle and the inner peripheral surface of the boundary gas supply pipe and is formed to communicate with the premix chamber. Burner for mixed combustion of ammonia and coal. In claim 2,
A portion of the high-temperature, low-oxygen boundary gas supplied to the pre-mix chamber is mixed with ammonia fuel gas through the inside of the ammonia burner nozzle through the pre-mix port and is injected into the reduction area located at the center of the furnace. become,
The remaining part of the high-temperature, low-oxygen boundary gas supplied to the premixing chamber passes through the space between the inner peripheral surface of the boundary gas supply pipe and the outer peripheral surface of the ammonia burner nozzle with the inflow amount controlled by the boundary gas flow control valve. A burner for mixed combustion of ammonia and coal, characterized in that it is configured to be sprayed toward the interface between ammonia fuel gas, coal, and primary air inside the furnace. In claim 2,
It further includes an ammonia supply pipe for supplying ammonia fuel gas toward the inside of the ammonia burner nozzle, and an ammonia flow control valve is installed between the ammonia burner nozzle and the ammonia supply pipe to control the supply amount of ammonia fuel gas. A burner for mixed combustion of ammonia and coal, characterized in that. In claim 4,
It further includes a flexible pipe connecting the ammonia burner nozzle and the ammonia supply pipe, and the ammonia flow control valve is installed between the ammonia supply pipe and the flexible pipe for mixed combustion of ammonia and coal. burner. In claim 4,
It further includes an ammonia burner nozzle position adjusting device installed to adjust the axial position of the ammonia burner nozzle, and the ammonia burner nozzle position adjusting device is configured to adjust the axial position of the ammonia burner nozzle. A burner for mixed combustion of ammonia and coal, characterized in that it is configured to fine-tune the direction position with respect to the interior of the furnace of the boiler. In claim 6,
It further includes a high-temperature low-oxygen gas supply pipe for supplying high-temperature low-oxygen gas toward the inside of the boundary gas supply pipe, and a high-temperature low-oxygen gas supply pipe for controlling the supply amount of the high-temperature low-oxygen gas between the high-temperature low-oxygen gas supply pipe and the boundary gas supply pipe. A burner for mixed combustion of ammonia and coal, characterized in that a low-oxygen gas control valve is installed. In claim 1,
Ammonia and coal, further comprising a purge gas supply pipe for supplying a purge gas to the inside of the boundary gas supply pipe, and a purge gas valve for controlling the supply amount of the purge gas is installed in the purge gas supply pipe. Burner for mixed combustion. In claim 7,
A gas distributor installed in a branched manner to the exhaust system of the boiler to receive low-temperature, low-oxygen exhaust gas;
a gas heat exchanger installed to heat exchange the low-temperature hypoxic gas provided through the gas distributor with the high-temperature hypoxic gas of the boiler; and
A burner for mixed combustion of ammonia and coal, further comprising a high-temperature, low-oxygen gas pipe installed to supply the high-temperature, low-oxygen gas that has passed through the gas heat exchanger to the high-temperature, low-oxygen gas supply pipe. In claim 9,
It further includes a low-temperature hypoxic gas pipe connecting the gas distributor and the gas heat exchanger to enable communication, and a gas distribution flow control valve for controlling the supply amount of the low-temperature hypoxic gas is installed in the low-temperature hypoxic gas pipe. A burner for mixed combustion of ammonia and coal. In claim 10,
It further includes a bypass pipe that bypasses the gas heat exchanger from the low-temperature low-oxygen gas pipe, and the bypass pipe is configured to control the temperature of the high-temperature low-oxygen gas provided to the high-temperature low-oxygen gas supply pipe through the high-temperature low-oxygen gas pipe. A burner for mixed combustion of ammonia and coal, characterized in that a bypass flow control valve is installed for the combustion. A burner for mixed combustion of ammonia and coal according to claim 11;
An ammonia flow transmitter that detects and transmits ammonia flow rate information provided through the ammonia supply pipe;
A coal flow rate and property information transmitter that detects and transmits the supply amount and property information of coal provided to the coal burner nozzle;
An exhaust gas analysis information transmitter installed in the exhaust system of the boiler to detect and transmit the temperature, flow rate, and chemical species information of the exhaust gas;
a gas flow rate controller that adjusts the supply amount of low-temperature hypoxic gas provided to the low-temperature hypoxic gas pipe based on operation control of the gas distribution flow control valve;
a bypass flow controller that adjusts the temperature of the high-temperature low-oxygen gas provided to the high-temperature low-oxygen gas supply pipe through the high-temperature low-oxygen gas pipe based on operation control of the bypass flow control valve;
a boundary gas flow controller that adjusts the supply amount of boundary gas provided into the furnace through the boundary gas supply pipe based on operation control of the boundary gas flow control valve;
a nozzle tip position controller that adjusts the axial position of the ammonia burner nozzle tip based on operation control of the ammonia burner nozzle position adjusting device; and
Ammonia flow rate information transmitted from the ammonia flow rate transmitter, coal supply and property information transmitted from the coal flow rate and property information transmitter, and exhaust gas temperature, flow rate, and chemical species information transmitted from the exhaust gas analysis information transmitter. Based on the gas flow rate controller, the bypass flow controller, the permanent boundary gas flow controller, and the nozzle tip position controller, it further includes an operation control device that outputs a control signal for operation control for the mixed combustion of ammonia and coal. A supply system for high-temperature, low-oxygen gas applied to the burner.