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锡林浩特二电厂是1989年11月投产的新厂,燃用当地胜利煤矿的褐煤.l~#炉为北京 B&W公司制造的65t/h煤粉炉.制粉系统为风扇磨直吹式.采用正四角直吹式燃烧器.炉内呈切国燃烧.每个燃烧器的一次风喷口分上下二层,二次风喷口分上中下三层,中二次风喷口带有一支 300kg/h机械雾化油枪,供点火和稳燃用.一、存在的主要问题1、锅炉燃烧不稳定,经常发生灭火,特别是低负荷和冬季运行更严重.运行人员怕 相似文献
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针对燃用低质煤的煤粉炉提出采用脉动方式喷入二次风,强化炉内混合与扩散过程,强化燃烧,减小燃烧损失,提高锅炉运行的经济性.并对脉动二次风燃烧方式的实施与对锅炉运行的影响进行了探讨. 相似文献
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《湖北电力》2017,(5)
对一台1 000 MW超超临界前后墙旋流对冲燃烧煤粉锅炉,在HT-NR3型低NO_x旋流煤粉燃烧器不同外二次风叶片开度下(50%、75%、100%),进行了炉内流动、燃烧、传热与NO_x排放特性数值模拟研究。模拟结果与试验测量值符合性较好,结果表明:外二次风旋流叶片开度对炉内燃烧特性及排放特性影响较大,旋流叶片开度减小导致旋流强度增大,卷吸高温烟气增多,煤粉着火距离减小,煤粉燃烧剧烈程度增加,炉内主燃区温度水平升高,燃尽区温度水平有所降低,煤粉燃烬率增大,NO_x排放量减小。实际运行中采用外二次风开度为50%的高旋流强度工况,达到了燃烧稳定、高效低NO_x的目的。 相似文献
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四角切圆燃烧锅炉在低氮燃烧改造后,主燃烧区为欠氧燃烧,当燃用低灰熔点或低挥发分煤时易引起煤粉贴壁燃烧现象以及水冷壁出现强还原性气氛,导致锅炉高温腐蚀和结渣/结焦。为此提出了墙式风燃烧辅助系统,将二次风在水平方向进一步分级,增加直接进入煤粉射流中下游的墙式风,优化炉内燃烧组织。在某600MW锅炉热态运行下,进行有无墙式风的对比性试验,然后进行低灰熔点煤的掺配试验,结果表明:墙式风燃烧辅助系统既提高了一次风射流煤粉着火稳燃能力,又提高了射流中下游燃烧所需氧量,减小实际切圆,有效解决水冷壁高温腐蚀和结焦问题。在锅炉安全运行下,燃用低灰熔点银南煤与银北煤的最大安全掺配比为9:1,降低了燃煤发电成本,还在一定程度上降低了NOx排放量。 相似文献
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负荷分配对流化床-煤粉复合燃烧锅炉热力特性的影响 总被引:1,自引:0,他引:1
针对树皮流化床-煤粉复合燃烧锅炉的特点,提出了流化床按基本蒸汽负荷设计的思路。以75t/h树皮流化床-煤粉复合燃烧锅炉为例,预测了总蒸汽负荷一定条件下,燃树皮产汽负荷与燃煤产汽负荷变化时锅炉的热力特性。计算表明,随着燃树皮产汽负荷的增加,煤粉炉膛的绝热燃烧温度和流化床温度降低;而炉膛出口烟温、排烟温度、空气预热器出口风温和高温风风量、减温水量等热力参数升高,但变化幅度不大,证明了前述设计思路的可行性。在一定的基本蒸汽负荷下,燃树皮产汽负荷的上限值可根据流化床中树皮的稳定燃烧温度和减温系统的工作能力来确定。 相似文献
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P. V. Roslyakov 《Thermal Engineering》2016,63(7):495-510
Realization of the ecologically safe technologies for fuel combustion in the steam boiler furnaces and the effective ways for treatment of flue gases at modern thermal power plants have been analyzed. The administrative and legal measures to stimulate introduction of the technologies for air protection at TPPs have been considered. It has been shown that both the primary intrafurnace measures for nitrogen oxide suppression and the secondary flue gas treatment methods are needed to meet the modern ecological standards. Examples of the environmentally safe methods for flame combustion of gas-oil and solid fuels in the boiler furnaces have been provided. The effective methods and units to treat flue gases from nitrogen and sulfur oxides and flue ash have been considered. It has been demonstrated that realization of the measures for air protection should be accompanied by introduction of the systems for continuous instrumentation control of the composition of combustion products in the gas path of boiler units and for monitoring of atmospheric emissions. 相似文献
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介绍了焚烧城市生活垃圾掺烧20%煤的CFB锅炉的运行情况。描述了锅炉负荷、汽温、汽压和汽包水位的调节过程,并详细地说明了燃料量、风量、床温和流化质量等的控制方法。 相似文献
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在一台75t/h循环流化床锅炉上进行了燃用不同煤种、不同负荷和不同一次风量对床温影响的试验。试验表明,煤挥发分含量较低时,床温沿炉膛高度逐渐降低,但返料温度明显升高;负荷提高,床温整体升高,但炉膛底部与中部的温差减小;一次风量增加,会导致烟气从密相区带走的热量大于燃烧放热而使床温降低。 相似文献
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The desire to increase the efficiency of using the heat of burned solid fuel leads to the significant growth of the initial steam parameter at steam-turbine plants. At the maximum temperatures of fresh and secondary steam of 700–720°С, the price of connecting of steam pipelines between the boiler and turbine is up to 20% of the price of a power plant unit, which dictates the necessity to decrease their length. One of the methods to achieve this is the application of an inverter firebox. An M-shaped profile of boiler, allowing one to decrease the length of heat-resistant steam pipelines, was developed at NRU MPEI. A distinctive feature of the profile is two inclined connecting gas flues between the firebox and convective shaft, starting from the gas windows located in the lower third of the firebox height. The boiler was designed for the steam production of 2493 t/h with the parameters of fresh steam of 35 MPa and 710°C. Thermal and aerodynamic calculations made it possible to get the sizes of boiler and dimensions of heating surfaces, and they also allow one to get the values of temperatures in the characteristic points along the gas path. On the basis of the results of calculations, the coefficient of efficiency of the boiler was 93.07% and the fuel consumption was 91.13 kg/s. For this boiler, the technology of effective stepwise burning of coal in a direct-flow-vortex torch (DFVT) in a system of vertical and horizontal tangential torches in the mode of solid slag removal, previously successively used in boilers with a traditional profile and upgraded to an inverter firebox, is proposed. The layouts of the direct-flow burners and nozzles for even and odd vertical sections of the firebox and also in a horizontal section were proposed. Organization of staged air supply in the vertical direction with a high fraction of in-firebox recycle of hot gases leads to low concentration of nitrogen oxides. 相似文献
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某电厂HG240/100-1型燃煤锅炉,8只旋流燃烧采用两侧墙对冲布置;锅炉投产时制粉系统选型为直吹式制粉系统,后改为中间储仓式制粉系统;设计煤种为鹤岗烟煤,后燃用过淮南烟煤、淮北烟煤及混煤等。由于煤源不固定,煤质波动大,煤质特性远远偏离了设计煤种,造成锅炉存在很多问题。主要问题是凝渣管结渣和主蒸汽温度偏高。为了寻找问题的原因,本文通过现场测试、调节,从试验的角度分析了锅炉结渣和主蒸汽温度偏高的原因。结果表明,在电厂正常运行工况下,甲侧的风粉浓度比乙侧的低,导致甲侧的温度水平较高,甲侧受热面易结渣;乙侧烟气量较多,烟速增大,与受热面间交换的热量增加,是导致乙侧主汽温度偏高的主要原因。 相似文献
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