一种节油 /气点火稳燃低氮旋流煤粉燃烧器 Fuel-saving/gas ignition stable combustion low-nitrogen swirl pulverized coal burner
技术领域 Technical field
本发明涉及一种煤粉燃烧器, 尤其是一种适用于电站锅炉的节油 /气点火稳燃低氮旋 流煤粉燃烧器。 The invention relates to a pulverized coal burner, in particular to a fuel-saving/gas ignition stable combustion low-nitrogen swirl pulverized coal burner suitable for a power station boiler.
背景技术 Background technique
目前世界上电站煤粉锅炉普遍采用大油枪实现启动和低负荷稳燃。 据统计, 国内电 力系统每年用于锅炉调试、 启动、 低负荷稳燃和停炉助燃用油高达近千万吨, 占全国总 燃油消耗量的 15 %, 价值数百亿元人民币, 消耗了大量的燃油资源, 也使发电成本大大 提高。 中国煤炭资源比油、 气资源丰富得多, 以煤炭为主的能源消费结构在近几十年仍 然不会改变。 发电行业是燃油消耗量很大的行业, 减少燃油消耗和降低发电成本是大势 所趋。 以煤代油的节油点火技术近年来在国内迅速发展, 取得了良好的应用效果。 At present, power pulverized coal boilers in the world generally use large oil guns to achieve start-up and low-load steady combustion. According to statistics, the domestic power system is used for boiler commissioning, start-up, low-load stable combustion and shutdown combustion-supporting oil up to nearly 10 million tons per year, accounting for 15% of the country's total fuel consumption, worth tens of billions of yuan, and consumed a lot. The fuel resources also greatly increase the cost of power generation. China's coal resources are much richer than oil and gas resources. The coal-based energy consumption structure will not change in recent decades. The power generation industry is an industry with a large fuel consumption. It is a general trend to reduce fuel consumption and reduce power generation costs. The fuel-saving ignition technology based on coal instead of oil has developed rapidly in China in recent years and achieved good application results.
近几年, 随着人们对环境保护的重视, 降低氮氧化物的排放成为与节油点火并驾齐 驱的关键技术。 但目前很多低氮燃烧器存在磨损严重、 喷口结渣和高温腐蚀的问题, 对 煤种适应性不强。 In recent years, with the emphasis on environmental protection, reducing nitrogen oxide emissions has become a key technology in keeping with fuel economy. However, many low-nitrogen burners currently have problems of severe wear, nozzle slagging and high-temperature corrosion, and are not adaptable to coal types.
目前就墙式燃烧锅炉的旋流燃烧器而言, 节油点火技术的应用方法是将一排旋流燃 烧器的一次风部分拆除更换为节油点火煤粉燃烧器, 而节油点火煤粉燃烧器在锅炉正常 运行时并不具备低氮燃烧器的性能结构, 往往使进行节油点火技术应用的整排旋流燃烧 器的低氮和稳燃性能有所下降。 At present, in the case of a swirl burner for a wall-fired boiler, the application of the fuel-saving ignition technique is to replace the primary air portion of a row of swirl burners with a fuel-efficient ignition pulverized coal burner, and the fuel-saving ignition pulverized coal. The burner does not have the performance structure of the low-nitrogen burner during normal operation of the boiler, which tends to reduce the low nitrogen and stable combustion performance of the entire row of swirl burners used for fuel-saving ignition technology.
发明内容 Summary of the invention
技术问题: 本发明的目的是针对已有技术中存在问题, 提供一种结构简单、 煤种适 应性强、 具有低氮氧化物排放的节油 /气点火稳燃低氮旋流煤粉燃烧器。 Technical Problem: The object of the present invention is to provide a fuel-saving/gas ignition stable combustion low-nitrogen swirl pulverized coal burner with simple structure, strong adaptability of coal type, and low nitrogen oxide emission. .
技术问方案: 本发明的节油 /气点火稳燃低氮旋流煤粉燃烧器, 包括一次风通道、 多 通道二次进风管、 伸入一次风通道内的油 /气燃烧器, 一次风通道、 多通道二次进风管的 出口端均为扩椎结构, 所述的一次风通道内的强化燃烧室入口通道内壁上均布有一圈成 水平角排列的整流叶片, 所述的油 /气燃烧器前部外壁上均布有一圈成倾斜角排列的旋流 叶片, 旋流叶片的前端距离油 /气燃烧器前端的长度大于或等于整流叶片的长度, 旋流叶 片的外径小于整流叶片的内径; 所述的多通道二次进风管包括套装在一次风通道外圆周 上的直流二次进风管, 直流二次进风管的外圆周上设有内部装有内旋流叶片的旋流内二 次进风管,旋流内二次进风管的外圆周上设有内部装有外旋流叶片的旋流外二次进风管; 所述直流二次进风管入口处设有前后运动调节风门一风量的直流风门调节杆, 所述的旋
流内二次进风管入口处设有前后运动调节风门二风量的旋流风门调节杆; 所述的内旋流 叶片上设有轴向角度可内旋流叶片调节杆, 外旋流叶片上设有轴向角度可外旋流叶片调 节杆。 Technical Solution: The fuel-saving/gas ignition stable combustion low-nitrogen pulverized coal pulverized coal burner of the invention comprises a primary air passage, a multi-channel secondary air inlet pipe, and an oil/gas burner extending into the primary air passage, once The outlet end of the air passage and the multi-channel secondary air inlet duct are all expanded structures, and the inner wall of the enhanced combustion chamber inlet passage in the primary air passage is uniformly provided with a plurality of rectifying blades arranged at a horizontal angle, the oil The outer wall of the front part of the gas burner is uniformly arranged with a swirling vane arranged at an oblique angle. The front end of the swirl vane is longer than or equal to the length of the rectifying vane, and the outer diameter of the swirling vane is smaller than The inner diameter of the rectifying blade; the multi-channel secondary air inlet pipe comprises a DC secondary air inlet pipe disposed on the outer circumference of the primary air passage, and the inner circumference of the direct current secondary air inlet pipe is provided with an internal swirling flow a secondary air inlet pipe in the swirling flow of the blade, and a swirling outer secondary air inlet pipe with an outer swirling blade inside the outer circumference of the secondary air inlet pipe in the swirling flow; the DC secondary air inlet pipe There is a front and rear movement regulating damper at the entrance. DC throttle adjustment lever, said spin The swirling damper adjusting rod of the front and rear movement regulating damper two air flow is provided at the inlet of the secondary air inlet pipe; the inner swirling vane is provided with an axial angle inner swirling vane adjusting rod, and the outer swirling vane An external angle swirling vane adjustment rod is provided.
所述一次风通道的外壁上设有可使油 /气燃烧器进入一次风通道内前后移动的导套。 有益效果: 本发明燃烧器具有高效和低氮氧化物排放的特点, 解决了目前很多低氮 燃烧器存在的磨损严重, 喷口结渣和高温腐蚀的问题, 通过调节杆可调节内外二次风的 风量和 /或旋流强度, 控制燃烧器喷口中心高温烟气回流区和一二次风的混合时机, 可适 应不同煤种的着火和稳燃要求。 通过在一次风通道内设置位置可调的强化燃烧的燃油 /气 燃烧器, 通过调整该燃烧器的位置, 使节油 /气点火稳燃低氮旋流煤粉燃烧器兼顾节油 / 气和低氮的特性。 旋流强度可以在线调节, 通过调节二次风的旋流强度, 使燃烧器在喷 口中心形成合理的高温烟气回流区, 提供煤粉着火和稳燃的稳定热源。 燃烧器一、 二次 风处均设置一定角度的喷口扩椎结构, 能有效控制二次风与煤粉的适时混合, 同时使喷 口处水冷壁区域处于氧化气氛中, 有效防止燃烧器区域水冷壁的结渣和高温腐蚀发生。 该发明着火稳燃性能好, 煤质适应性强, 同时具有低氮氧化物排放的优点。 其结构简单, 煤种适应性强,使用效果好, 在本技术领域内具有广泛的实用性。 The outer wall of the primary air passage is provided with a guide sleeve that allows the oil/gas burner to move back and forth into the primary air passage. Advantageous Effects: The burner of the invention has the characteristics of high efficiency and low nitrogen oxide emission, and solves the problems of serious wear of many low-nitrogen burners at present, nozzle slagging and high-temperature corrosion, and the internal and external secondary air can be adjusted by adjusting the rod. The air volume and / or swirl intensity, control the mixing time of the high temperature flue gas recirculation zone and the secondary air in the center of the burner nozzle, can adapt to the ignition and stable combustion requirements of different coal types. By setting a position-adjustable enhanced combustion fuel/gas burner in the primary air passage, by adjusting the position of the burner, the fuel-saving/air-ignition stabilized low-nitrogen swirl pulverized coal burner combines fuel economy and gas Low nitrogen characteristics. The swirling intensity can be adjusted online. By adjusting the swirling intensity of the secondary air, the burner forms a reasonable high-temperature flue gas recirculation zone at the center of the nozzle, providing a stable heat source for pulverized coal ignition and stable combustion. The burner 1 and the secondary air are all provided with a certain angle of the nozzle expansion structure, which can effectively control the timely mixing of the secondary air and the coal powder, and at the same time, the water wall area of the nozzle is in an oxidizing atmosphere, effectively preventing the water wall of the burner area. Slag formation and high temperature corrosion occur. The invention has good ignition stability, strong coal quality adaptability and low nitrogen oxide emission. The utility model has the advantages of simple structure, strong adaptability of coal type and good use effect, and has wide practicality in the technical field.
附图说明 DRAWINGS
图 1为本发明的燃烧器结构示意图。 图 2为本发明的燃烧器工作过程位置结构示意图。 图中: 1一油 /气燃烧器, 2 一次风通道, 3 内旋流叶片调节杆, 4一外旋流叶 片调节杆, 5—旋流风门调节杆, 6—直流风门调节杆, 7—风门一, 8—二次进风管, 9一风门二, 10 旋流内二次进风管, 11 内旋流叶片, 12 旋流外二次进风管, 13 外旋流叶片, 14一旋流叶片, 15—整流叶片, 16 强化燃烧室, 17 扩椎。 具体实施方式 Figure 1 is a schematic view showing the structure of a burner of the present invention. 2 is a schematic view showing the position structure of the working process of the burner of the present invention. In the figure: 1 oil/gas burner, 2 primary air passage, 3 internal swirl vane adjustment rod, 4 external swirl vane adjustment rod, 5-swirl damper adjustment rod, 6-DC damper adjustment rod, 7-翼门一, 8—Secondary air inlet pipe, 9一风门二, 10 Circulating secondary air inlet pipe, 11 internal swirling blade, 12 swirling outer secondary air inlet pipe, 13 external swirling blade, 14一Swirl blades, 15 - rectifying blades, 16 fortified combustion chambers, 17 for expanding the vertebrae. detailed description
下面结合附图对本发明的一个实施例作进一步的描述: 本发明的节油 /气点火稳燃低氮旋流煤粉燃烧器, 主要由油 /气燃烧器 1、一次风通道 2、 风门、 调节杆、 二次进风管 8、 旋流内二次进风管 10、 旋流外二次进风管 12和旋流 叶片构成。 所述油 /气燃烧器 1伸入到一次风通道 2内, 一次风通道 2的水平管段外壁上 设有可使油 /气燃烧器 1进入一次风通道 2内前后移动的导套,油 /气燃烧器 1的轴心线与
一次风通道 2的水平管段的轴心线重合。 一次风通道 2、 二次进风管 8、 旋流内二次进风 管 10、 旋流外二次进风管 12的出口端均为扩椎结构, 扩椎角均为 30° 。 所述的一次风 通道 2内的强化燃烧室 16入口通道内壁上均布有一圈成水平角排列的整流叶片 15,所述 的油 /气燃烧器 1前部外壁上均布有一圈成倾斜角排列的旋流叶片 14, 旋流叶片 14的前 端距离油 /气燃烧器 1前端的长度大于或等于整流叶片 15的长度, 旋流叶片 14的外径小 于整流叶片 15的内径; 所述油 /气燃烧器 1与一次风通道 2入口处的配合为可前后移动、 调整旋流叶片 14与整流叶片 15之间相对位置的动配合, 油 /气燃烧器 2前后移动的距离 大于整流叶片 15的长度。所述的多通道二次进风管包括套装在一次风通道 2外圆周上的 直流二次进风管 8, 直流二次进风管 8的外圆周上设有内部装有内旋流叶片 11的旋流内 二次进风管 10, 旋流内二次进风管 10的外圆周上设有内部装有外旋流叶片 13的旋流外 二次进风管 12; 所述直流二次进风管 8入口处设有前后运动调节风门一 7风量的直流风 门调节杆 6, 所述的旋流内二次进风管 10入口处设有前后运动调节风门二 9风量的旋流 风门调节杆 5; 所述的内旋流叶片 11上设有轴向角度可内旋流叶片调节杆 3, 外旋流叶 片 13上设有轴向角度可外旋流叶片调节杆 4。 An embodiment of the present invention will be further described below with reference to the accompanying drawings: The fuel-saving/gas ignition stable combustion low-nitrogen swirl pulverized coal burner of the present invention mainly comprises an oil/gas burner 1, a primary air passage 2, a damper, The adjusting rod, the secondary air inlet pipe 8, the secondary air inlet pipe 10 in the swirling flow, the outer air inlet pipe 12 and the swirling vane are formed. The oil/gas burner 1 extends into the primary air passage 2, and the outer wall of the horizontal pipe section of the primary air passage 2 is provided with a guide sleeve for moving the oil/gas burner 1 into the primary air passage 2, and oil/ The axial line of the gas burner 1 The axial line of the horizontal pipe section of the primary air passage 2 coincides. The outlet end of the primary air passage 2, the secondary air inlet duct 8, the secondary air inlet duct 10 in the swirling flow, and the secondary air inlet duct 12 in the swirling flow are all dilated vertebrae structures, and the dilatation angles are all 30°. The inner wall of the inlet passage of the reinforced combustion chamber 16 in the primary air passage 2 is evenly distributed with a plurality of rectifying blades 15 arranged at a horizontal angle, and the front outer wall of the oil/gas burner 1 is uniformly distributed with a circle at an oblique angle. Arranging the swirling vanes 14, the front end of the swirling vanes 14 is greater than or equal to the length of the front end of the oil/gas burner 1 and the outer diameter of the swirling vane 14 is smaller than the inner diameter of the rectifying vane 15; The cooperation between the gas burner 1 and the inlet of the primary air passage 2 is a dynamic fit that can move back and forth to adjust the relative position between the swirling vane 14 and the rectifying vane 15, and the oil/gas burner 2 moves forward and backward by a distance greater than that of the rectifying vane 15 length. The multi-channel secondary air inlet pipe comprises a DC secondary air inlet pipe 8 disposed on an outer circumference of the primary air passage 2, and an inner swirling blade 11 is disposed on an outer circumference of the direct current secondary air inlet pipe 8. The swirling inner secondary air inlet pipe 10, the outer circumference of the secondary air inlet pipe 10 in the swirling flow is provided with a swirling outer secondary air inlet pipe 12 with an outer swirling vane 13 therein; The inlet of the air inlet pipe 8 is provided with a DC damper adjusting lever 6 for adjusting the damper of the front and rear movements, and a swirling damper for adjusting the damper of the front and rear movement regulating damper is provided at the entrance of the secondary air inlet pipe 10 in the swirling flow. The inner swirling vane 11 is provided with an axial angle inner swirling vane adjusting rod 3, and the outer swirling vane 13 is provided with an axial angle outer swirling vane adjusting rod 4.
工作原理:节油 /气点火稳燃低氮旋流煤粉燃烧器中的油 /气燃烧器 1安装在一次风通 道 2内, 旋流内、外二次风均采用轴向角度可调叶片形式, 分别通过内旋流叶片调节杆 3 和外旋流叶片调节杆 4进行调节, 旋流内、 外二次风风量比例通过旋流风门调节杆 5带 动风门二 9前后运动实现调节。 直流内二次风通过直流风门调节杆 6带动风门一 7前后 运动调节风量; 调整油 /气燃烧器 1 的前后位置, 带动旋流叶片 14位移, 从而带动旋流 叶片 14与整流叶片 15之间相对位置的变化。 Working principle: oil/gas ignition stable combustion The low-nitrogen swirling pulverized coal burner oil/gas burner 1 is installed in the primary air passage 2, and the inner and outer secondary air in the swirling flow are all adjustable with axial angle. The form is adjusted by the inner swirling blade adjusting rod 3 and the outer swirling blade adjusting rod 4, respectively, and the ratio of the inner and outer secondary air volume of the swirling flow is adjusted by the swirling damper adjusting rod 5 to move the damper 2 and 9 forward and backward. The secondary air in the direct current through the DC damper adjusting rod 6 drives the damper 7 to adjust the air volume before and after; adjusting the front and rear position of the oil/gas burner 1 to drive the displacement of the swirling vane 14 to drive the swirling vane 14 and the rectifying vane 15 Relative position changes.
锅炉冷态启动时, 燃烧器如图 1所示位置, 油 /气燃烧器 1为投运状态, 一次风粉进 入一次风道 2后首先经过旋流叶片 14产生旋转运动, 从旋流叶片 14出来后, 进入整流 叶片 15,在整流叶片 15的整流作用下,在整流叶片 15的迎风面形成与整流叶片 15数量 相同的多股浓相煤粉气流, 在整流叶片 15的背面形成多股淡相煤粉气流。浓相煤粉气流 和淡相煤粉气流进入强化燃烧室 16, 在强化燃烧室 16内被油 /气燃烧器 2的火焰点燃后 喷出燃烧器。 此时, 通过直流风门调节杆 6带动风门一 7运动, 使直流风量较大, 冷却 强化燃烧室的壁面, 保护其不超温、 安全运行。 由于煤粉是浓相、 淡相间隔分布, 形成 了有利于降低 NOx产生的良好环境, 可大大降低 NOx的生成。 强化燃烧室 16相对于锅 炉炉膛是一个极狭小的空间环境, 因此用少量的油 /气火焰即可以将强化燃烧室 16 内部
升温至煤粉的着火温度以上, 实现用少量的油 /气将煤粉点燃的节油 /气目的, 从而以煤代 油 /气, 利用煤粉火焰的热量再将锅炉炉膛升温至煤粉的着火温度以上, 再投入其它煤粉 燃烧器的煤粉, 完成锅炉的启动过程。 When the boiler is started coldly, the burner is in the position shown in Fig. 1, and the oil/gas burner 1 is in the commissioning state. After the primary air powder enters the primary air passage 2, the rotary motion is first generated by the swirling vane 14, from the swirling vane 14 After coming out, the rectifying blades 15 are introduced, and under the rectifying action of the rectifying blades 15, a plurality of dense phase pulverized coal gas streams having the same number as the rectifying blades 15 are formed on the windward surface of the rectifying blades 15, and a plurality of light rays are formed on the back surface of the rectifying blades 15. Phase coal powder flow. The dense phase pulverized coal gas stream and the light phase pulverized coal gas stream enter the enhanced combustion chamber 16, and are ignited by the flame of the oil/gas burner 2 in the enhanced combustion chamber 16, and then ejected from the burner. At this time, the damper 7 is driven by the DC damper adjusting lever 6, so that the direct current air volume is large, and the wall surface of the combustion chamber is cooled and cooled to protect it from over-temperature and safe operation. Since the pulverized coal is densely phased and has a light phase interval distribution, a good environment is formed which is favorable for reducing NOx production, and the generation of NOx can be greatly reduced. The enhanced combustion chamber 16 is a very narrow space environment relative to the boiler furnace, so that the interior of the enhanced combustion chamber 16 can be reinforced with a small amount of oil/gas flame. Warming up to above the ignition temperature of the pulverized coal, to achieve the fuel-saving/gas purpose of igniting the pulverized coal with a small amount of oil/gas, thereby replacing the heating of the boiler with the heat of the pulverized coal by using the heat of the pulverized coal flame/gas. Above the ignition temperature, the pulverized coal of other pulverized coal burners is put into operation to complete the startup process of the boiler.
锅炉启动过程完成后, 油 /气燃烧器 1为停运状态, 油 /气燃烧器 1向前移动至强化燃 烧室 16内, 如图 2所示位置, 一次风粉进入一次风道 2后首先经过整流叶片 15, 产生比 较均匀的煤粉气流, 从整流叶片 15出来的风进入旋流叶片 14后产生旋转运动, 煤粉在 离心力的作用下形成外浓内淡的分布,这种煤粉分布方式与二次风配合可以降低 NOx的 生成。 调节直流风门调节杆 6带动风门一 7运动, 使直流内二次风减小; 调节旋流风门 调节杆 5带动风门二 9运动, 使旋流内二次风比例减小, 旋流外二次风比例加大; 内旋 流叶片调节杆 3和外旋流叶片调节杆 4使旋流内二次风和旋流外二次风的旋流强度均较 小。 这样可使二次风和煤粉火焰的混合减弱, 延迟燃烧, 降低 NOx的生成。 相反的调节 方式, 可以提高整个气流的旋流强度, 强化煤粉和空气的混合, 强化前期燃烧, 使飞灰 可燃物得到降低, 提高燃烧效率。 通过调试调节杆减小或加大风流强弱两种方式, 可以 找到平衡 NOx和飞灰可燃物的最佳理想点。 After the boiler start-up process is completed, the oil/gas burner 1 is in a stopped state, and the oil/gas burner 1 is moved forward to the enhanced combustion chamber 16, as shown in Fig. 2, after the primary air powder enters the primary air passage 2, first After the rectifying blade 15, a relatively uniform pulverized coal gas flow is generated, and the wind from the rectifying blade 15 enters the swirling vane 14 to generate a rotary motion, and the pulverized coal forms a distribution of the outer rich and the inner light under the action of the centrifugal force. The combination with the secondary air can reduce the formation of NOx. Adjusting the DC damper adjusting rod 6 to drive the damper 7 movement, so that the secondary air in the DC is reduced; adjusting the swirling damper adjusting rod 5 to drive the damper 2 to move, so that the proportion of the secondary air in the swirl is reduced, and the swirling is twice The proportion of wind is increased; the inner swirling vane adjusting rod 3 and the outer swirling vane adjusting rod 4 make the swirling intensity of the secondary air in the swirling flow and the secondary air in the swirling flow smaller. This weakens the mixing of the secondary air and the pulverized coal flame, delays combustion, and reduces NOx formation. The opposite adjustment method can improve the swirling intensity of the entire airflow, strengthen the mixing of pulverized coal and air, strengthen the pre-combustion, reduce the fly ash combustibles, and improve the combustion efficiency. By adjusting the adjustment rod to reduce or increase the intensity of the wind, the best ideal point for balancing NOx and fly ash combustibles can be found.
一、 二次风道喷口均为扩椎 7结构, 扩椎 7的扩椎角为 30° , 通过外扩结构使一、 二次风的混合延迟, 使燃烧器喷口区域形成风包粉的流场结构, 达到着火初期一次风内 部形成缺氧气氛, 使初期的氮氧化物得到充分还原, 同时利用外扩结构形成的风墙达到 隔离煤粉颗粒和喷口水冷壁区域管屏的目的, 从而可有效缓解燃烧器区域水冷壁结焦和 高温腐蚀的几率。
1. The secondary air duct spouts are all structures of the expanding vertebrae 7. The expansion angle of the expanding vertebra 7 is 30°. The mixing of the secondary air is delayed by the external expansion structure, so that the flow of the wind-blown powder is formed in the burner nozzle area. The field structure reaches an oxygen-deficient atmosphere inside the primary air at the beginning of the fire, so that the initial nitrogen oxides are fully reduced, and the wind wall formed by the externally expanded structure achieves the purpose of isolating the pulverized coal particles and the nozzle wall of the nozzle water wall region, thereby Effectively alleviate the chance of water wall coking and high temperature corrosion in the burner area.