共查询到19条相似文献,搜索用时 109 毫秒
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该通对对阳泉第二发电厂双进双出磨煤机招标情况的介绍,论述了不同生产厂家的双进双出磨煤机的结构,特点,并对磨煤机的性能参数进行了比较,可为今后选择该类磨煤机提供参考。 相似文献
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对双进双出磨煤机进行了冷态模型试验研究,得到了滚筒式磨煤机中气固两相流场的运行特性,进一步弄清了不同流场运行方式对磨煤机干燥、研磨和气力输送过程的影响。所得结果对双进双出磨煤机的设计和控制具有指导作用。 相似文献
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根据钢球磨煤机噪声的形成机理,对目前国内外控制钢球磨煤机噪声的技术进行了评述。重点论述了磨煤机衬板的结构及材质对降噪效果的影响,指出无源噪声控制技术是一种行之有效的控制技术,阐述了各种新型降噪材料的降噪效果,认为从噪声源和振动源上对噪声进行控制,开发出性能更优越的降噪材料是钢球磨煤机噪声控制技术的发展方向。 相似文献
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基于 40· 5 3型双进双出磨煤机实际工况条件 ,对双进双出磨煤机内流场进行了数值模拟。通过分析磨煤机入口风速和磨煤机填充率对内部流场的影响规律 ,获得了一些有利于磨煤机的研磨、干燥、气力选粉和输粉过程的相关条件。图 5表 2参 7 相似文献
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作为电场锅炉制粉系统的关键环节,磨煤机在具体运行中会受电负荷、供热量等因素的影响,需要不断对设备进行调整与启停,这导致磨煤机经常会出现堵塞现象.而容易引发磨煤机堵塞的原因,还有其自身结构的缺陷、煤质的波动及人员操作失误或对其运行状态判断失误的.在具体应用中,磨煤机堵塞现象无法彻底根除,其中一次风管是磨煤机中易造成堵塞的... 相似文献
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Pre-treatments, such as torrefaction, can improve biomass fuels properties. Dedicated and coal co-firing plants, in which pulverised biomass and torrefied biomass can be used, are exposed to explosion hazards during handling, storage and transport from the mills to the boiler. Data on the explosion characteristics of biomass and torrefied biomass are scarce. This study presents explosion characteristics (maximum explosion pressure, deflagration index and minimum explosible concentration) of two torrefied wood samples and compares their reactivity to that of their corresponding untreated biomass materials and to a sample of Kellingley coal. Torrefied biomass samples showed higher reactivity, overpressures were around 9 bar (0.9 MPa, 1 bar = 105 Pa) for all biomass samples irrespective of size or sample composition. Derived laminar burning velocities ranged between 0.1–0.12 m s−1, and were therefore similar to that of coal (0.12 m s−1). The differences in explosion reactivity influence the design of explosion protection measures and can be used to introduce suitable modifications for safe operations with torrefied biomass. 相似文献
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众所周知,影响风扇磨煤机的性能参数主要有:煤质特性,风扇磨的结构特笥和运动特性,传统的风扇磨的选型往往是根据煤的可磨度,煤粉细度和原煤水份等系数来确定风扇磨的性能参数,实践证明,该选型方法是不完善的,其通用性较差,采用煤种的试磨方法是风扇磨选型和制粉系统设计较为可靠的方法,本文介绍了根据流动和几何相似原理建立起的S02.300型风扇磨试验系统,通过对扎赉诺尔和零林河褐煤的试验验证,把试磨的有关参数移值到大型风扇磨的选型设计中去,为设计院根据煤种合理选择风扇磨及其制粉系统设计提供依据。 相似文献
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九江公司三期两台350 MW机组锅炉为美国FOSTER WHEELER公司生产的W型火焰、一次中间再热、平衡通风、固态排渣、亚临界参数自然循环汽包炉,配备4套正压直吹式制粉系统,两台离心式一次风机,四台双进双出钢球磨煤机。设计煤种低位发热量为24849 kJ/kg,挥发分为10.7%,为降低入炉煤成本和适应复杂多变的煤炭市场,实际入炉煤种为2~3种原煤按一定比例物理掺配后的混煤。对混煤煤质的约束条件、混煤的燃烧特性及变化规律,燃烧混煤可能出现的问题及应对措施进行讨论。 相似文献
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对两种典型无烟煤进行了工业分析及热重试验,应用双混合分数(PDF)模型对不同无烟煤掺烧方式下直吹式制粉系统W型火焰锅炉进行了数值模拟,得到了炉内烟气温度场、氧体积分数分布场及烟气速度场.结果表明:两种无烟煤的工业分析参数基本相当,但可磨性和燃烧特性存在明显差异;在炉前掺烧方式下,炉膛温度、氧体积分数分布以及速度场均较对称,但煤粉燃尽率比分磨掺烧方式下明显偏低,炉膛出口烟气温度比分磨掺烧方式下偏高;在分磨掺烧方式下,磨煤机运行模式对燃烧经济性有较大影响;无烟煤与无烟煤也存在混煤掺烧优化的空间,分磨掺烧方式可提高燃烧经济性. 相似文献
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M. Siddhartha Bhatt 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2013,35(1):43-58
This article reports the secondary energy effects (wear/erosion/abrasion, slagging, and fouling) of ash in coal on the energy performance of coal fired thermal power plants of capacity range 30–500 MW. It also gives the extent of capacity reduction in equipment due to firing of coals with higher ash contents. At an ash content of 75% in coal, the effects on the system (without fuel oil support) follow: (a) decrease in Hardgrove index from 80 to 44; (b) 20% of the specific energy consumption (SEC) of induced draft (ID) fans, 10%–12% of that of forced draft (FD) and primary air (PA) fans, 17% of that of drum mills, and 12%–13% of that of ball-race mills and bowl mills, are accounted for by wear/erosion/abrasion effects; (c) decrease of fan efficiencies by 5%–6% points due to wear/erosion/abrasion effects; (d) capacity loss originating from wear/erosion/abrasion effects alone is 8% due to ID fans, 1% due to PA fans, and 6% due to mills; (e) fouling effects are high fouling factor, decrease in boiler efficiency by 3%, and capacity reduction of 2%; and (f) CFs based on overall unit performance are 31% for units below 210 MW, 26% for 210 MW units, and 40% for 500 MW. Considering the capacity restrictions due to individual equipment, CF at an ash content of 57% is 85% due to the boiler fans, 84% due to Raymond bowl mills and drum type ball mills, 71% due to slow speed large ball and race mills, and 88% due to ash slurry pumps. When the coal exceeds 70% and tends toward 76%, the heating value of coal tends toward zero. The effects of slagging (independent of ash content in coal) area 20% decrease in boiler water wall loading, a 3.5% points decrease in boiler efficiency, and capacity reduction of 14%. 相似文献
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