CN111947136A - W flame boiler with flexible peak-shaving self-stabilizing combustion performance and combustion method - Google Patents
W flame boiler with flexible peak-shaving self-stabilizing combustion performance and combustion method Download PDFInfo
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- CN111947136A CN111947136A CN202010877330.4A CN202010877330A CN111947136A CN 111947136 A CN111947136 A CN 111947136A CN 202010877330 A CN202010877330 A CN 202010877330A CN 111947136 A CN111947136 A CN 111947136A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C7/00—Combustion apparatus characterised by arrangements for air supply
- F23C7/002—Combustion apparatus characterised by arrangements for air supply the air being submitted to a rotary or spinning motion
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L9/00—Passages or apertures for delivering secondary air for completing combustion of fuel
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Abstract
A W flame boiler with flexible peak regulation and self-stabilization combustion performance and a combustion method relate to the technical field of industrial pulverized coal boilers. The invention aims to solve the problems that the existing W flame pot has poor ultra-low load stable combustion capability and the flexibility peak load regulation can not reach 20%. The invention comprises a plurality of cyclone tube shade combined type pulverized coal burners and a plurality of secondary oil air nozzles, wherein a plurality of cyclone tube shade combined type pulverized coal burners are respectively arranged on a front furnace arch and a rear furnace arch, the outer side of each cyclone tube shade combined type pulverized coal burner is provided with one secondary oil air nozzle, the secondary oil air nozzles are arranged on a furnace body, and the inclination angles of the secondary oil air nozzles are adjustable. The invention is used for industrial pulverized coal boilers.
Description
Technical Field
The invention relates to the technical field of industrial pulverized coal boilers, in particular to a W flame boiler with flexible peak regulation and self-stabilizing combustion performance and a combustion method.
Background
The W-flame boiler is a power station boiler which is introduced from the areas of North Africa and Western Europe and the like from the nineties of the twenty-century in China and is specially designed for burning low-volatile and difficult-to-burn coal types such as lean coal, anthracite and the like. Because the anthracite and lean coal have compact and stable lithofacies structures, small porosity and low reactivity, the problems of difficult ignition, difficult stable combustion and difficult burnout exist in actual combustion, higher ignition temperature and burnout temperature are needed, and the coal powder burnout time is longer. When the boiler is operated under low load, the temperature of the hot air is reduced because the quantity of fuel fed into the boiler is less, and the primary air and the secondary air are reduced along with the reduction of the quantity of the fuel. The oxygen content in the furnace is relatively high, and the heat load in the furnace and the temperature of a hearth are low. The combustion stability of the boiler will be further deteriorated and even cause fire extinguishment. Therefore, the pulverized coal stream is less likely to catch fire and stabilize combustion during low load operation of the W-fired utility boiler than other coal-fired utility boilers.
However, in recent years, with the intervention of large-scale renewable energy sources, the power system in china has changed greatly. The power generation capacity of renewable energy sources accounts for an increasing proportion of the power grid. However, the instability of the output of renewable energy power generation poses a great challenge to the regulation capability of the power system due to the limitations of the power generation mode. In addition, in recent years, while wind power is continuously and rapidly developed, serious wind abandon problems occur in partial areas, and consumption becomes a key factor for restricting the development of new energy resources such as wind power. Therefore, in order to adapt to the high-speed development of renewable energy sources and improve the consumption capacity of a power system for the renewable energy sources, the government requires that the flexibility peak shaving capacity of the boiler reaches about 20% of the full load.
Practical production shows that the minimum load of the W-flame boiler can only be maintained at about 50% of full load under the condition of ensuring the stable operation of the boiler, and the W-flame boiler can not meet relevant government requirements. Therefore, it is necessary to develop a new type of W-flame boiler with flexible peak shaving technology to improve the peak shaving capability of the boiler.
Disclosure of Invention
The invention aims to solve the problems that the existing W flame boiler is poor in ultra-low load stable combustion capacity and incapable of reaching 20% of flexible peak-load regulation load, and further provides a W flame boiler with flexible peak-load regulation and self-stable combustion performance and a combustion method.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a W flame boiler with flexible peak regulation and self-stabilization performance comprises an upper hearth, a lower hearth, a front furnace arch, a rear furnace arch, a front wall, a rear wall and a multi-layer arch lower secondary air nozzle, wherein the upper hearth, the front furnace arch, the front wall, the lower hearth, the rear wall and the rear furnace arch form a boiler body, and the front wall and the rear wall are respectively provided with the multi-layer arch lower secondary air nozzle; the W flame boiler with the flexibility peak regulation and self-stabilization performance further comprises a plurality of cyclone tube shade combined type pulverized coal burners and a plurality of oil secondary air nozzles, a front furnace arch and a rear furnace arch are respectively provided with the plurality of cyclone tube shade combined type pulverized coal burners, the outer side of each cyclone tube shade combined type pulverized coal burner is provided with one oil secondary air nozzle, the oil secondary air nozzles are arranged on a furnace body, and the inclination angles of the oil secondary air nozzles are adjustable.
A combustion method of a W flame boiler with flexible peak-shaving self-stabilizing combustion performance comprises the following steps:
when the boiler is started, the oil secondary air door is opened, the oil secondary air nozzle and the dense coal powder airflow nozzle are arranged at an included angle of 10-15 degrees, oil secondary air is sprayed into the boiler from the oil secondary air nozzle and is supplied for oil sprayed out of a large oil gun arranged in the oil secondary air nozzle to be combusted, the output of the oil gun is 1.5t/h, and the oil flame heats the cold boiler; when the temperature of the flue gas of the hearth reaches a preset value, the coal dust airflow in the primary air pipe enters a cyclone thick-thin combined coal dust burner, under the separation action of the cyclone, the primary air coal dust airflow is divided into a thick coal dust airflow and a thin coal dust airflow, an air volume adjusting valve is completely closed, the thick coal dust airflow is downwards sprayed into the hearth from a thick coal dust airflow nozzle, the thin coal dust airflow does not exist, oil flame meets the thick coal dust airflow at an angle of 10-15 degrees, and the thick coal dust airflow is ignited; under the combustion supporting of oil flame, the coal feeding amount is gradually increased, the boiler load is gradually increased, when the boiler load reaches 50%, an oil secondary air door is closed, oil spraying of an oil gun is stopped, an included angle between an oil secondary air nozzle and a dense pulverized coal airflow nozzle is kept unchanged, and the boiler reaches full load by means of heat released by pulverized coal combustion;
when the full-load operation of the boiler is carried out, primary air of the boiler accounts for 20-22% of the total air rate of the boiler, the air quantity regulating valve is kept to be completely closed, primary air pulverized coal airflow is sprayed out from a dense pulverized coal airflow nozzle, the air speed is 27-32 m/s, and the mass flow ratio of pulverized coal mass flow to air for conveying pulverized coal is 0.4: 1-0.6: 1;
when the load of the boiler is reduced to 50% load and the boiler is operated in a full load interval, the air quantity regulating valve and the oil secondary air valve are kept completely closed, and an oil secondary air nozzle and a dense coal powder airflow nozzle are arranged in an included angle of 10-15 degrees; when the load of the boiler is reduced to the range from 20% load to 50% load, along with the gradual reduction of the coal powder feeding amount, the air quantity regulating valve and the oil secondary air valve are gradually opened, the opening increasing value of the oil secondary air valve is in direct proportion to the load reduction amplitude, the regulating pull rod on the oil secondary air nozzle is regulated, the supporting rod rotates relatively in the sleeve, the included angle between the oil secondary air nozzle and the dense coal powder air flow nozzle is reduced, and the angle reduction amplitude is in direct proportion to the load reduction amplitude.
A combustion method of a W flame boiler with flexible peak-shaving self-stabilizing combustion performance comprises the following steps:
when the load of a boiler reaches 20% of ultra-low load operation, an air volume adjusting valve is completely opened, under the separation action of a cyclone cylinder, primary air pulverized coal airflow is divided into thick pulverized coal airflow and thin pulverized coal airflow, the thick pulverized coal airflow downwards sprays into a hearth from a thick pulverized coal airflow nozzle, the thin pulverized coal airflow upwards sprays into the hearth through an exhaust nozzle, the air rate of the thick pulverized coal airflow accounts for 18.5-25.9% of the total primary air rate, the air rate of the thin pulverized coal airflow accounts for 74.1-81.5% of the total primary air rate, the air speeds of the thick pulverized coal airflow and the thin pulverized coal airflow are both 5-7 m/s, the thick pulverized coal airflow accounts for 90% of the total coal feeding amount, the thin pulverized coal airflow accounts for 10% of the total coal feeding amount, and the mass flow ratio of the mass flow of the thick pulverized coal: 1-2.4: 1, firing a dense coal powder air flow at a position 6500-600 mm away from a dense coal powder air flow nozzle, adjusting an adjusting pull rod on an oil secondary air nozzle, relatively rotating a support rod in a sleeve, parallelly arranging the oil secondary air nozzle and the dense coal powder air flow nozzle, adjusting alpha to be 0 degrees, adjusting the distance L between the oil secondary air nozzle and the dense coal powder air flow nozzle and the inner diameter d of the oil secondary air nozzle 10 to meet the condition that L/d is 0.3/1-0.6/1, opening the oil secondary air door, and controlling the oil secondary air speed to be 23-26 m/s.
A combustion method of a W flame boiler with flexible peak-shaving self-stabilizing combustion performance comprises the following steps:
after the operation of the boiler is finished under 20% ultra-low load, the load needs to be increased, along with the gradual increase of the coal powder supply, an air quantity adjusting valve and an oil secondary air valve are gradually closed, the opening degree reduction value of the air quantity adjusting valve and the load increase amplitude are in direct proportion, an adjusting pull rod on an oil secondary air nozzle is adjusted, a supporting rod rotates relatively in a sleeve, the included angle between the oil secondary air nozzle and a dense coal powder air flow nozzle is increased, the angle increase amplitude is in direct proportion to the load increase amplitude, after the load is increased to 50% of the load, the air quantity adjusting valve is closed, the dense coal powder air flow is downwards sprayed into a hearth from the dense coal powder air flow nozzle, no light coal powder air flow exists, the adjusting pull rod on the oil secondary air nozzle is adjusted, the supporting rod rotates relatively in the sleeve, the oil secondary air nozzle and the dense coal powder air flow nozzle.
Compared with the prior art, the invention has the following beneficial effects:
1. the thick coal powder airflow is arranged on the fire-facing side, which is favorable for ignition and stable combustion of the coal powder airflow.
As shown in fig. 1, each cyclone thick and thin pulverized coal burner of the conventional FW type W flame boiler includes a thick pulverized coal stream nozzle and a dead gas nozzle. Wherein the exhaust gas nozzle is arranged at the side close to the center of the hearth, and the dense coal powder airflow nozzle is arranged at the side close to the wall of the front wall and the rear wall of the lower hearth. The central area of the hearth has high smoke temperature, and the side hearths of the front wall and the rear wall have low temperature. The thick coal powder airflow is arranged on the front wall side and the rear wall side with low temperature, and the thick coal powder airflow is slow in temperature rise, late in ignition and poor in stable combustion.
As shown in fig. 2 and 3, the exhaust nozzle 7 is coaxially arranged inside the rich coal airflow nozzle 6. The dense pulverized coal airflow is arranged on the central side of the hearth, the smoke temperature of the central area of the hearth is high, the dense pulverized coal airflow is fast in temperature rise, early in ignition and good in stable combustion.
2. The down-stroke depth of flame can be ensured while the dense coal dust airflow is on fire in time.
Under the original structure, the dense pulverized coal airflow is ensured to be ignited in time and large-depth downward rushing of flame is realized. The air flow speed of the concentrated coal powder under the full load condition is 27-32 m/s, and the mass flow ratio of the coal powder mass flow to the air for conveying the coal powder is 0.4: 1-0.6: 1, the concentration of the coal powder is low, the speed is high, the ignition of the coal powder airflow is not facilitated, but the temperature of a hearth is 1600-1700 ℃ under the full load condition, and the stable operation of the boiler can still be realized. At about 50% load, the airflow speed of the concentrated coal powder is reduced to 22-25 m/s, and the mass flow ratio of the coal powder to the air for conveying the coal powder is 0.3: 1-0.5: 1, although the temperature of the hearth is reduced relative to the full load, the temperature of the hearth is still as high as 1400-1450 ℃, and the stable operation of the boiler can be realized. At 20% ultra-low load, the temperature of the hearth is further reduced, generally 1150-1250 ℃, and the propagation speed of the pulverized coal flame is reduced to about 8 m/s. In order to realize the large-depth undershoot of flame, the air speed of the thick pulverized coal airflow is still kept at 22-25 m/s, and the mass flow ratio of pulverized coal mass flow to pulverized coal conveying air is 0.15: 1-0.3: 1, the ignition of the rich coal dust airflow is difficult due to the following reasons: (1) the mass flow ratio of the pulverized coal to the air conveying the pulverized coal is 0.15: 1-0.3: 1, the ignition temperature is about 1000 ℃. The coal powder has low concentration and high ignition temperature, and requires much ignition heat. (2) The air speed of the concentrated coal dust airflow is still kept at 22-25 m/s, the residence time in a high-temperature area is short, the temperature of a hearth is only 1150-1250 ℃, and the concentrated coal dust airflow is difficult to heat to the ignition temperature. (3) The necessary conditions for achieving stable combustion: the velocity of the pulverized coal gas flow in the ignition area is equal to or lower than the propagation velocity of the pulverized coal flame. The air speed of the concentrated coal powder airflow is still kept at 22-25 m/s, and the flame propagation speed of the coal powder is far higher than about 8m/s within the ignition distance of 500-600mm at the outlet of the concentrated coal powder airflow. Therefore, the high wind speed of the concentrated coal powder airflow meets the requirement of large-depth undershoot of flame, but cannot realize timely ignition and stable combustion of the 20% ultra-low load concentrated coal powder airflow. In order to meet the requirements of timely ignition and stable combustion of the 20% ultra-low load concentrated pulverized coal airflow, the airflow speed of the concentrated pulverized coal airflow is reduced to 5-7 m/s under the original structure. Because the air flow velocity of the concentrated coal dust is too low and the momentum is small, the downward-rushing depth of the concentrated coal dust air flow is greatly reduced, the retention time of the concentrated coal dust air flow in a lower hearth is short, the heat released by combustion is small, and the smoke temperature of the lower hearth can be reduced to below 1000 ℃ at this time, so that the ignition and the combustion of the coal dust air flow are difficult to maintain. Therefore, the low wind speed of the concentrated coal powder airflow is difficult to meet the requirement of large-depth undershoot of flame, so that the flue gas temperature of a hearth is further reduced, and the 20% ultralow load stable combustion cannot be realized. Therefore, under the original structure, the thick pulverized coal airflow can not only ensure timely ignition, but also realize large-depth undershoot of flame, and can not realize 20% ultra-low load stable combustion.
The air flow velocity of the thick and thin pulverized coal is 5-7 m/s, the undershoot momentum is small, and the undershoot depth is small. The secondary oil air speed is 23-26 m/s, the speed is high, and the momentum is large. The secondary oil air nozzles and the dense coal powder air flow nozzles are arranged in parallel, the distance L between the secondary oil air nozzles and the dense coal powder air flow nozzles and the diameter d of the secondary oil air nozzles meet the requirement that L/d is 0.3-0.6 (see figure 4). The dense coal dust airflow starts to be mixed with the secondary oil air when being ejected from the nozzle for 500-600mm and descends under the carrying of the secondary oil air, so that the downward-punching depth of the flame is ensured. The flame is deeply downwards pushed to the vicinity of the cold ash hopper and then turns upwards, the residence time of the concentrated coal powder airflow in the lower hearth is long, the combustion time is long, and the heat released by combustion is large, so that the lower hearth is ensured to have higher flue gas temperature, and the higher flue gas temperature is favorable for the concentrated coal powder airflow to catch fire. Therefore, the secondary oil air nozzles and the dense coal powder air flow nozzles are arranged in parallel, and the down-stroke depth of the flame is ensured.
The invention can ensure the thick coal powder airflow to catch fire in time for the following reasons: (1) the mass flow ratio of the coal dust in the concentrated coal dust airflow to the mass flow ratio of the air for conveying the coal dust is 1.5: 1-2.4: 1. the higher the coal powder concentration is, the lower the ignition temperature is, which is about 600 ℃, and compared with the original structure, the ignition temperature is reduced by about 400 ℃, which is beneficial to the timely ignition of dense coal powder airflow. (2) The air flow speed of the concentrated coal powder is 5-7 m/s, when the air flow speed of the concentrated coal powder is 20-25 m/s, the staying time of the concentrated coal powder air flow in a high-temperature area is prolonged by about 4 times, the longer the staying time in the high-temperature area is, the longer the coal powder heating time is, the larger the temperature rise in a unit distance is, and the timely ignition of the concentrated coal powder air flow is facilitated. (3) The air flow velocity of the concentrated coal dust is 5-7 m/s, and is lower than the coal dust flame propagation velocity of about 8m/s, so that the air flow velocity of the coal dust in an ignition area is equal to or lower than the coal dust flame propagation velocity. (4) After the thick coal airflow is ignited, the thin coal airflow and the oil secondary air are gradually mixed with the thick coal airflow and supply air required by the thick coal airflow for combustion, the thick coal airflow is combusted in a lower hearth to release more heat, and the lower hearth is high in temperature and favorable for the thick coal airflow to be ignited.
The invention ensures the timely ignition of the thick pulverized coal airflow, realizes the larger undershoot depth of the flame, and can realize the stable combustion of 20 percent of ultralow load.
3. The high-load and about 50% low-load operation mode is not influenced.
Under the conditions of high load and about 50% low load, the operation mode of the traditional boiler can be completely recovered by closing the air quantity regulating valve 9 and recovering the secondary oil air nozzle 11 to be arranged at an included angle of 10-15 degrees with the concentrated coal powder air flow nozzle 6. The air speed of the thick coal powder airflow under the full load condition is about 27-32 m/s, and the mass flow ratio of the coal powder mass flow to the air for conveying the coal powder is 0.4: 1-0.6: 1. at about 50% load, the airflow speed of the concentrated coal powder is reduced to 22-25 m/s, and the mass flow ratio of the coal powder to the air for conveying the coal powder is 0.3: 1-0.5: 1, the stable and efficient operation of the boiler is not influenced.
4. The adjusting means is reliable, and large-range lifting load can be stably realized.
Under the original structure, the load is lifted only by adjusting the airflow speed of the concentrated coal powder, the adjusting means is single, the operation in the load range of 50% -100% can be realized only, and the requirement of flexible peak regulation is difficult to meet. The invention realizes the operation in the load range of 20-100% by adjusting the included angles of the air quantity adjusting valve 9, the oil secondary air door 11, the oil secondary air nozzle 10 and the dense pulverized coal airflow nozzle 6, and meets the requirement of flexible peak regulation.
Drawings
FIG. 1 is a schematic cross-sectional flow field diagram of a conventional FW type W flame boiler;
FIG. 2 is a schematic cross-sectional flow field of the W flame boiler of the present invention;
FIG. 3 is an enlarged view at I of FIG. 2 at full load;
FIG. 4 is an enlarged view at I of FIG. 2 under 20% ultra low load conditions;
fig. 5 is a schematic view of fig. 4 in the direction of a.
Detailed Description
The first embodiment is as follows: the embodiment is described with reference to fig. 2 to 5, and the W flame boiler with flexible peak regulation and self-stable combustion performance in the embodiment comprises an upper hearth 1, a lower hearth 2, a front furnace arch 3, a rear furnace arch 4, a front wall, a rear wall and a multi-layer arch lower secondary air nozzle 8, wherein the upper hearth 1, the front furnace arch 3, the front wall, the lower hearth 2, the rear wall and the rear furnace arch 4 form a boiler body, and the front wall and the rear wall are respectively provided with the multi-layer arch lower secondary air nozzle 8; the W flame boiler with the flexibility peak regulation and self-stabilization performance further comprises a plurality of cyclone tube shade combined type pulverized coal burners 5 and a plurality of secondary oil air nozzles 10, a front furnace arch 3 and a rear furnace arch 4 are respectively provided with the plurality of cyclone tube shade combined type pulverized coal burners 5, the outer side of each cyclone tube shade combined type pulverized coal burner 5 is provided with one secondary oil air nozzle 10, the secondary oil air nozzles 10 are arranged on a furnace body, and the inclination angles of the secondary oil air nozzles 10 are adjustable.
The multiple cyclone tube shade combined pulverized coal burners 5 on the front furnace arch 3 are uniformly distributed along the length direction, and the multiple cyclone tube shade combined pulverized coal burners 5 on the rear furnace arch 4 are uniformly distributed along the length direction.
The secondary air spout 8 sets up along the direction of height under the multilayer arch on the front wall, and the secondary air spout 8 sets up along the direction of height under the multilayer arch on the back wall, and every layer of secondary air spout 8 all includes a plurality of secondary air spouts 8 under encircleing along length direction equipartition setting under encircleing, and every axis and the horizontal plane parallel arrangement of secondary air spout 8 under encircleing.
The second embodiment is as follows: the embodiment is described with reference to fig. 2 to 5, the cyclone thick-thin combined type coal powder burner 5 of the embodiment includes a cyclone, a thick coal powder airflow spout 6 and an exhaust gas spout 7, one end of the thick coal powder airflow spout 6 is communicated with the furnace body, the other end of the thick coal powder airflow spout 6 is communicated with the bottom of the cyclone, one end of the exhaust gas spout 7 is coaxially disposed inside the thick coal powder airflow spout 6 and is communicated with the furnace body, and the other end of the exhaust gas spout 7 penetrates through the side wall of the cyclone and is communicated with the top end of the cyclone. Technical features not disclosed in the present embodiment are the same as those of the first embodiment.
The cross section area of the exhaust gas nozzle 7 is 2.9-4.4 times of the cross section area between the outer side wall of the exhaust gas nozzle 7 and the inner side wall of the concentrated pulverized coal airflow nozzle 6.
And a primary air pipe is arranged on the side wall of the cyclone cylinder, and primary air pulverized coal airflow enters the cyclone cylinder through the primary air pipe.
The third concrete implementation mode: the present embodiment is described with reference to fig. 2 to 5, and an air volume adjusting valve 9 is provided on the exhaust nozzle 7 in the present embodiment. The technical features not disclosed in the present embodiment are the same as those of the second embodiment.
The air quantity in the exhaust nozzle 7 can be adjusted by 0-100% by controlling the opening of the air quantity adjusting valve 9.
The fourth concrete implementation mode: the embodiment is described with reference to fig. 2 to 5, the secondary oil air nozzle 10 of the embodiment is provided with an adjusting pull rod 10-1 and a sleeve 10-2, the adjusting pull rod 10-1 is fixedly connected to the outer side wall of the secondary oil air nozzle 10, the sleeve 10-2 is fixedly connected to the inner side wall of the secondary oil air nozzle 10, the sleeve 10-2 is sleeved on a support rod 10-3, the support rod 10-3 is in a shape of a Chinese character 'ji', and two ends of the support rod 10-3 are fixedly connected to the cyclone tube dense-thin combined pulverized coal burner 5. The technical features not disclosed in this embodiment are the same as those of the first, second, or third embodiment.
The fifth concrete implementation mode: the present embodiment is described with reference to fig. 2 to 5, an included angle formed by a central axis of the oil secondary air nozzle 10 and a central axis of the concentrated pulverized coal airflow nozzle 6 in the present embodiment is α, and α is adjustable within a range of 0 ° to 25 °. Technical features not disclosed in the present embodiment are the same as those of the first embodiment.
The sixth specific implementation mode: the present embodiment is described with reference to fig. 2 to 5, and the oil secondary air port 10 of the present embodiment is provided with an oil secondary air door 11. The technical features not disclosed in this embodiment are the same as those of the first, second, third or fifth embodiment.
The seventh embodiment: the present embodiment is described with reference to fig. 2 to 5, and the combustion method of the W-flame boiler with flexible peak-shaving self-stabilizing combustion performance according to the present embodiment includes the following steps:
when the boiler is started, the oil secondary air door 11 is opened, the oil secondary air nozzle 10 and the dense coal powder air flow nozzle 6 are arranged at an included angle of 10-15 degrees, oil secondary air is sprayed into the boiler from the oil secondary air nozzle 10 and supplied to oil sprayed out from a large oil gun arranged in the oil secondary air nozzle 10 for combustion, the output of the oil gun is 1.5t/h, and oil flame heats the cold boiler; when the temperature of the flue gas in the hearth reaches a preset value, the coal dust airflow in the primary air pipe enters a cyclone thick-thin combined coal dust burner 5, under the separation action of the cyclone, the primary air coal dust airflow is divided into a thick coal dust airflow and a thin coal dust airflow, an air volume adjusting valve 9 is completely closed, the thick coal dust airflow is downwards sprayed into the hearth from a thick coal dust airflow nozzle 6, no thin coal dust airflow exists, oil flame meets the thick coal dust airflow at an angle of 10-15 degrees, and the thick coal dust airflow is ignited; under the combustion supporting of oil flame, the coal feeding amount is gradually increased, the boiler load is gradually increased, when the boiler load reaches 50%, the oil secondary air door 11 is closed, the oil gun stops oil injection, the included angle between the oil secondary air nozzle 10 and the dense pulverized coal airflow nozzle 6 is kept unchanged, and the boiler reaches full load by means of heat released by pulverized coal combustion;
when the full-load operation of the boiler is carried out, primary air of the boiler accounts for 20-22% of the total air rate of the boiler, the air quantity regulating valve 9 is kept to be completely closed, primary air pulverized coal airflow is sprayed out from the dense pulverized coal airflow nozzle 6, the air speed is 27-32 m/s, and the mass flow ratio of pulverized coal mass flow to air for conveying pulverized coal is 0.4: 1-0.6: 1, unit is kg (coal)/kg (air);
when the load of the boiler is reduced to 50% load and the boiler is operated in a full load interval, the air quantity regulating valve 9 and the oil secondary air door 11 are kept completely closed, and the oil secondary air nozzle 10 and the dense coal powder air flow nozzle 6 are arranged in an included angle of 10-15 degrees; when the load of the boiler is reduced to the range from 20% load to 50% load, along with the gradual reduction of the coal powder feeding amount, the air quantity regulating valve 9 and the oil secondary air door 11 are gradually opened, the opening increasing value of the air quantity regulating valve is in direct proportion to the load reduction amplitude, the regulating pull rod 10-1 on the oil secondary air nozzle 10 is regulated, the support rod 10-3 rotates in the sleeve 10-2 relatively, the included angle between the oil secondary air nozzle 10 and the dense coal powder airflow nozzle 6 is reduced, and the angle reduction amplitude is in direct proportion to the load reduction amplitude.
The specific implementation mode is eight: the present embodiment is described with reference to fig. 2 to 5, and the combustion method of the W-flame boiler with flexible peak-shaving self-stabilizing combustion performance according to the present embodiment includes the following steps:
when the load of a boiler reaches 20% of ultra-low load operation, an air volume adjusting valve 9 is completely opened, under the separation action of a cyclone, primary air pulverized coal airflow is divided into thick pulverized coal airflow and thin pulverized coal airflow, the thick pulverized coal airflow downwards sprays into a hearth from a thick pulverized coal airflow nozzle 6, the thin pulverized coal airflow upwards sprays into the hearth through an exhaust nozzle 7, the air volume of the thick pulverized coal airflow accounts for 18.5-25.9% of the total primary air rate, the air volume of the thin pulverized coal airflow accounts for 74.1-81.5% of the total primary air rate, the air speeds of the thick pulverized coal airflow and the thin pulverized coal airflow are both 5-7 m/s, the thick pulverized coal airflow accounts for 90% of the total coal supply, the thin pulverized coal airflow accounts for 10% of the total coal supply, and the mass flow ratio of the pulverized coal mass flow of the thick pulverized coal airflow: 1-2.4: the unit of the coal/kg (air) is that a concentrated coal powder air flow catches fire at a position 6500-600 mm away from a concentrated coal powder air flow nozzle, an adjusting pull rod 10-1 on an oil secondary air nozzle 10 is adjusted, a support rod 10-3 rotates relatively in a sleeve 10-2, the oil secondary air nozzle 10 and the concentrated coal powder air flow nozzle 6 are arranged in parallel, alpha is adjusted to be 0 degree, the distance L between the oil secondary air nozzle 10 and the concentrated coal powder air flow nozzle 6 and the inner diameter d of the oil secondary air nozzle 10 meet the condition that L/d is 0.3/1-0.6/1, an oil secondary air door 11 is opened, and the oil secondary air speed is 23-26 m/s.
The specific implementation method nine: the present embodiment is described with reference to fig. 2 to 5, and the combustion method of the W-flame boiler with flexible peak-shaving self-stabilizing combustion performance according to the present embodiment includes the following steps:
after the operation of the boiler with 20 percent of ultralow load is finished, the load is required to be increased, along with the gradual increase of the coal powder supply, the air quantity regulating valve 9 and the oil secondary air door 11 are gradually closed, the opening degree reduction value is in direct proportion to the load increase amplitude, the regulating pull rod 10-1 on the oil secondary air nozzle 10 is regulated, the supporting rod 10-3 rotates relatively in the sleeve 10-2, the included angle between the oil secondary air nozzle 10 and the dense coal powder air flow nozzle 6 is increased, the angle increase amplitude is in direct proportion to the load increase amplitude, after the load is increased to 50 percent of the load, the air quantity regulating valve 9 is closed, the dense coal powder air flow is downwards sprayed into a hearth from the dense coal powder air flow nozzle 6, no light coal powder air flow exists, the regulating pull rod 10-1 on the oil secondary air nozzle 10 is regulated, the supporting rod 10-3 rotates relatively in the sleeve 10-2, the oil secondary air nozzle 10 and the dense coal powder air flow, the oil secondary air door 11 is closed, and the supply of oil secondary air is stopped.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that features described in different dependent claims and herein may be combined in ways different from those described in the original claims. It is also to be understood that features described in connection with individual embodiments may be used in other described embodiments.
Claims (9)
1. A W flame boiler with flexible peak regulation and self-stabilization flame performance comprises an upper hearth (1), a lower hearth (2), a front furnace arch (3), a rear furnace arch (4), a front wall, a rear wall and a multi-layer arch lower secondary air nozzle (8), wherein the upper hearth (1), the front furnace arch (3), the front wall, the lower hearth (2), the rear wall and the rear furnace arch (4) form a boiler body, and the front wall and the rear wall are respectively provided with the multi-layer arch lower secondary air nozzle (8); the method is characterized in that: the W flame boiler with the flexibility peak regulation and self-stabilization combustion performance further comprises a plurality of cyclone tube shade combined type pulverized coal burners (5) and a plurality of oil secondary air nozzles (10), a front furnace arch (3) and a rear furnace arch (4) are respectively provided with the plurality of cyclone tube shade combined type pulverized coal burners (5), the outer side of each cyclone tube shade combined type pulverized coal burner (5) is provided with one oil secondary air nozzle (10), the oil secondary air nozzles (10) are arranged on a boiler body, and the inclination angles of the oil secondary air nozzles (10) are adjustable.
2. The W-flame boiler with flexible peak shaver self-stabilized flame performance as set forth in claim 1, wherein: the cyclone thick and thin combined type coal powder burner (5) comprises a cyclone, a thick coal powder airflow nozzle (6) and an exhaust gas nozzle (7), one end of the thick coal powder airflow nozzle (6) is communicated with a furnace body, the other end of the thick coal powder airflow nozzle (6) is communicated with the bottom of the cyclone, one end of the exhaust gas nozzle (7) is coaxially arranged inside the thick coal powder airflow nozzle (6) and communicated with the furnace body, and the other end of the exhaust gas nozzle (7) penetrates through the side wall of the cyclone and is communicated with the top end of the cyclone.
3. The W-flame boiler with flexible peak shaver self-stabilized flame performance as set forth in claim 2, wherein: and an air volume adjusting valve (9) is arranged on the exhaust gas nozzle (7).
4. A W-flame boiler with flexible peak shaver self-stabilized flame performance according to claim 1, 2 or 3, characterized in that: the secondary oil air nozzle (10) is provided with an adjusting pull rod (10-1) and a sleeve (10-2), the adjusting pull rod (10-1) is fixedly connected to the outer side wall of the secondary oil air nozzle (10), the sleeve (10-2) is fixedly connected to the inner side wall of the secondary oil air nozzle (10), the sleeve (10-2) is sleeved on the supporting rod (10-3), the supporting rod (10-3) is in a shape of a Chinese character 'ji', and two ends of the supporting rod (10-3) are fixedly connected to the thick-thin combined pulverized coal burner (5) of the cyclone cylinder.
5. The W-flame boiler with flexible peak shaver self-stabilized flame performance as set forth in claim 1, wherein: the included angle formed by the central axis of the oil secondary air nozzle (10) and the central axis of the concentrated coal powder airflow nozzle (6) is alpha, and the alpha is adjustable within the range of 0-25 degrees.
6. A W flame boiler with flexible peak shaver self-stabilized flame performance according to claim 1, 2, 3 or 5, characterized in that: and an oil secondary air door (11) is arranged on the oil secondary air nozzle (10).
7. A combustion method using a W-flame boiler having flexible peak-shaving self-stabilized combustion performance as claimed in any one of claims 1 to 6, characterized in that: the method comprises the following steps:
when the boiler is started, the oil secondary air door (11) is opened, the oil secondary air nozzle (10) and the dense coal powder air flow nozzle (6) are arranged at an included angle of 10-15 degrees, oil secondary air is sprayed into the boiler from the oil secondary air nozzle (10) and is supplied for oil sprayed out of a large oil gun arranged in the oil secondary air nozzle (10) to be combusted, the output of the oil gun is 1.5t/h, and the oil flame heats the cold boiler; when the temperature of the flue gas of the hearth reaches a preset value, the coal dust airflow in the primary air pipe enters a cyclone thick-thin combined coal dust burner (5), under the separation action of the cyclone, the primary air coal dust airflow is divided into a thick coal dust airflow and a thin coal dust airflow, an air volume adjusting valve (9) is completely closed, the thick coal dust airflow is downwards sprayed into the hearth from a thick coal dust airflow nozzle (6), the thin coal dust airflow does not exist, oil flame meets the thick coal dust airflow at an angle of 10-15 degrees, and the thick coal dust airflow is ignited; under the combustion supporting of oil flame, the coal feeding amount is gradually increased, the boiler load is gradually increased, when the boiler load reaches 50%, an oil secondary air door (11) is closed, oil injection of an oil gun is stopped, an included angle between an oil secondary air nozzle (10) and a dense coal powder airflow nozzle (6) is kept unchanged, and the boiler reaches full load by means of heat released by coal powder combustion;
when the full-load operation of the boiler is carried out, primary air of the boiler accounts for 20-22% of the total air rate of the boiler, an air quantity adjusting valve (9) is kept to be completely closed, primary air pulverized coal airflow is sprayed out from a dense pulverized coal airflow nozzle (6), the air speed is 27-32 m/s, and the mass flow ratio of pulverized coal mass flow to air for conveying pulverized coal is 0.4: 1-0.6: 1;
when the load of the boiler is reduced to 50% of the load and the boiler is operated in a full load interval, the air quantity regulating valve (9) and the oil secondary air door (11) are kept completely closed, and the oil secondary air nozzle (10) and the dense coal powder airflow nozzle (6) are arranged in an included angle of 10-15 degrees; when the load of the boiler is reduced to the range from 20% load to 50% load, along with the gradual reduction of the coal powder feeding amount, the air quantity regulating valve (9) and the oil secondary air door (11) are gradually opened, the opening increasing value of the air quantity regulating valve is in direct proportion to the load reduction amplitude, the regulating pull rod (10-1) on the oil secondary air nozzle (10) is regulated, the supporting rod (10-3) relatively rotates in the sleeve (10-2), the included angle between the oil secondary air nozzle (10) and the concentrated coal powder airflow nozzle (6) is reduced, and the angle reduction amplitude is in direct proportion to the load reduction amplitude.
8. A combustion method using a W-flame boiler having flexible peak-shaving self-stabilized combustion performance as claimed in any one of claims 1 to 6, characterized in that: the method comprises the following steps:
when the load of a boiler reaches 20% of ultra-low load operation, an air volume adjusting valve (9) is completely opened, under the separation action of a cyclone cylinder, primary air pulverized coal airflow is divided into thick pulverized coal airflow and thin pulverized coal airflow, the thick pulverized coal airflow downwards sprays into a hearth from a thick pulverized coal airflow nozzle (6), the thin pulverized coal airflow upwards sprays into the hearth through an exhaust gas nozzle (7), the air volume of the thick pulverized coal airflow accounts for 18.5-25.9% of the total primary air rate, the air volume of the thin pulverized coal airflow accounts for 74.1-81.5% of the total primary air rate, the air volumes of the thick and thin pulverized coal airflows are both 5-7 m/s, the thick pulverized coal airflow accounts for 90% of the total coal supply, the thin pulverized coal airflow accounts for 10% of the total coal supply, and the mass flow ratio of the mass flow of the thick pulverized coal airflow to the mass flow of: 1-2.4: 1, the concentrated coal powder airflow catches fire at a position 500-600mm away from a concentrated coal powder airflow nozzle (6), an adjusting pull rod (10-1) on an oil secondary air nozzle (10) is adjusted, a support rod (10-3) relatively rotates in a sleeve (10-2), the oil secondary air nozzle (10) and the concentrated coal powder airflow nozzle (6) are arranged in parallel, alpha is adjusted to be 0 degree, the distance L between the oil secondary air nozzle (10) and the concentrated coal powder airflow nozzle (6) and the inner diameter d of the oil secondary air nozzle (10) meet the condition that L/d is 0.3/1-0.6/1, an oil secondary air door (11) is opened, and the oil secondary air speed is 23-26 m/s.
9. A combustion method using a W-flame boiler having flexible peak-shaving self-stabilized combustion performance as claimed in any one of claims 1 to 6, characterized in that: the method comprises the following steps:
after the operation of the boiler with 20 percent of ultra-low load is finished, the load needs to be increased, along with the gradual increase of the coal powder supply, an air quantity adjusting valve (9) and an oil secondary air door (11) are gradually closed, the opening degree reduction value of the air quantity adjusting valve is in direct proportion to the load increase amplitude, an adjusting pull rod (10-1) on an oil secondary air nozzle (10) is adjusted, a support rod (10-3) relatively rotates in a sleeve (10-2), the included angle between the oil secondary air nozzle (10) and a dense coal powder air flow nozzle (6) is increased, the angle increase amplitude is in direct proportion to the load increase amplitude, when the load is increased to 50 percent of load, the air quantity adjusting valve (9) is closed, the dense coal powder air flow is downwards sprayed into a hearth from the dense coal powder air flow nozzle (6), no coal powder air flow exists, the adjusting pull rod (10-1) on the oil secondary air nozzle (10) is adjusted, the support rod (10-3, the oil secondary air nozzle (10) and the dense coal powder airflow nozzle (6) are arranged in an included angle of 10-15 degrees, the oil secondary air door (11) is closed, and the supply of oil secondary air is stopped.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113048509A (en) * | 2021-04-19 | 2021-06-29 | 贵州华电塘寨发电有限公司 | Air distribution control method and system for W-flame pulverized coal boiler |
| CN113883501A (en) * | 2021-11-01 | 2022-01-04 | 哈尔滨工业大学 | Boiler peak shaving method of W flame boiler for flexibly shaving peak by double-layer coal bunker |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007301327A (en) * | 2006-05-12 | 2007-11-22 | Tosaku Amakawa | Grill cooker |
| CN201281329Y (en) * | 2007-11-23 | 2009-07-29 | 华中科技大学 | Coal fine thickness segregated combustion device |
| CN201322295Y (en) * | 2008-07-08 | 2009-10-07 | 东方锅炉（集团）股份有限公司 | Pulverized coal combustion device |
| CN103672950A (en) * | 2013-10-17 | 2014-03-26 | 贵州电力试验研究院 | Method for combustion adjustment of W-type flame furnace with under-arch secondary air at adjustable down-dip angle |
| CN203744248U (en) * | 2014-01-28 | 2014-07-30 | 广西西江锅炉制造有限公司 | Heavy oil burner |
| CN104566358A (en) * | 2013-10-29 | 2015-04-29 | 烟台龙源电力技术股份有限公司 | Pulverized coal burner and boiler |
| CN111520705A (en) * | 2020-04-08 | 2020-08-11 | 哈尔滨工业大学 | Exhaust gas post-positioned W-flame boiler with arch-mounted secondary air nozzles and air distribution method |
-
2020
- 2020-08-27 CN CN202010877330.4A patent/CN111947136B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007301327A (en) * | 2006-05-12 | 2007-11-22 | Tosaku Amakawa | Grill cooker |
| CN201281329Y (en) * | 2007-11-23 | 2009-07-29 | 华中科技大学 | Coal fine thickness segregated combustion device |
| CN201322295Y (en) * | 2008-07-08 | 2009-10-07 | 东方锅炉（集团）股份有限公司 | Pulverized coal combustion device |
| CN103672950A (en) * | 2013-10-17 | 2014-03-26 | 贵州电力试验研究院 | Method for combustion adjustment of W-type flame furnace with under-arch secondary air at adjustable down-dip angle |
| CN104566358A (en) * | 2013-10-29 | 2015-04-29 | 烟台龙源电力技术股份有限公司 | Pulverized coal burner and boiler |
| CN203744248U (en) * | 2014-01-28 | 2014-07-30 | 广西西江锅炉制造有限公司 | Heavy oil burner |
| CN111520705A (en) * | 2020-04-08 | 2020-08-11 | 哈尔滨工业大学 | Exhaust gas post-positioned W-flame boiler with arch-mounted secondary air nozzles and air distribution method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113048509A (en) * | 2021-04-19 | 2021-06-29 | 贵州华电塘寨发电有限公司 | Air distribution control method and system for W-flame pulverized coal boiler |
| CN113883501A (en) * | 2021-11-01 | 2022-01-04 | 哈尔滨工业大学 | Boiler peak shaving method of W flame boiler for flexibly shaving peak by double-layer coal bunker |
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