循环流化床锅炉中灰循环倍率与炉膛传热系数

循环流化床锅炉中灰循环倍率不仅影响燃烧 ,而且还影响传热。炉膛传热系数是其热力计算的关键数据 ,根据现场测得的数据 ,并参照有关文献 ,提出了一个经验计算公式 ,在几台循环流化床锅炉上亦已证明是正确的     

循环流化床锅炉中灰平衡与灰循环倍率

灰循环倍率,不仅影响燃尽而且影响传热。它与飞灰份额、底灰份额的定义一样,都应以入炉灰量（含石灰石带入灰量）为基准。否则,无法计算烟气焓和烟气中飞欢浓度。必须指出,灰循环倍率不是人为选取的,它取决于分离器效率和飞灰份额。     

循环流化床锅炉循环倍率计算模型

基于循环流化床(CFB)锅炉热平衡,并结合物料平衡关系,提出了一种"四平衡双循环"迭代计算方法,该方法在计算出循环倍率的同时,也可以求出分离器、炉膛和密相区燃烧份额以及密相区过量空气系数等重要参数.根据某300 MW CFB锅炉现场运行数据建立模型进行计算,并分析了煤质和一次风、二次风配比对循环倍率的影响.结果表明:该计算模型能够准确计算出相关参数,且能合理反映以上因素对CFB锅炉循环倍率的影响,为循环倍率的控制与优化提供了一定的参考.     

循环流化床锅炉的循环倍率

循环倍率是循环流化床锅炉设计和运行控制的重要参数之一。本文对循环倍率与燃烧效率,循环倍率与密相区床温特性的关系进行了讨论。     

中倍率循环流化床锅炉的设计与应用

介绍了中倍率循环流化床锅炉的设计理念、结构布局及使用特点,并与高倍率循环流化床锅炉进行了比较,证明中倍率循环化床锅炉的发展潜力.     

循环流化床锅炉平衡计算与循环倍率的确定

正确地确定循环流化床锅炉的灰平衡计算方法和循环倍率，是循环流化床锅炉性能设计的基础。本文阐述了循环倍率和灰平衡计算的重要性，并从灰平衡计算方法分析出发，给出了各节点的灰量计算公式和循环倍率计算公式，找到了完善这一计算方法的关键参数。     

循环流化床锅炉循环倍率的设计分析

本文分析了循环流化床锅炉循环倍率与燃烧及炉内传热工况的密切关系,对返料器的设计作了一定的分析;并阐明了循环倍率与锅炉低负荷运行及炉内真空度沿高度变化的关系。     

低倍率循环流化床锅炉的研制与推广

文章着重介绍哈工大学研制的低倍率循环流化床锅炉及其运行经验。     

应用低倍率循环流化床燃烧技术改造锅炉

介绍了应用低倍率循环流化床燃烧技术改造l台链条炉及3台沸腾炉的情况，并取得了良好的经济效益，1年回收单台炉改造的投资成本。     

确定循环流化床锅炉循环倍率的若干问题

本文从分离器分离效率、燃烧效率和颗粒夹带等几个方面探讨了循环流化床锅炉确定循环倍率时应注意的几个问题并提出了相应的计算公式,以确保循环流化床锅炉实际运行时不至与设计工况偏差过大。     

Influence of CFB (circulating fluidized bed) boiler bottom ash heat recovery mode on thermal economy of units

CFB (circulating fluidized bed) boiler bottom ash contains large amounts of physical heat. A BAC (bottom ash cooler) is often used to treat high temperature bottom ash to reclaim heat, and to have the ash easily transported. The unit thermal economic indicators of three CFB power plants in China were derived based on heat balance calculation and analysis on the principled thermal system in turbine heat acceptance condition, taking the influence of two different bottom ash heat recovery modes into account. One of the two bottom ash heat recovery modes was the FBAC (fluidized bed ash cooler) mode, and the other was the RAC (rolling-cylinder ash cooler) mode. The results indicated that two modes both improved the thermal economy of units. Compared with the RAC mode, the FBAC mode obtained higher plant thermal efficiency, lower plant heat rate and less standard coal consumption. The standard coal consumption rate of the FBAC mode was less nearly 2 g/(kW h) than the RAC mode in the three CFB power plants, when the net calorific power of standard coal was 29.27 MJ/kg.     

Compositional and structural study of ash deposits spatially distributed in superheaters of a large biomass-fired CFB boiler

Recognizing the nature and formation progress of the ash deposits is essential to resolve the deposition problem hindering the wide application of large-scale biomass-fired boilers. Therefore, the ash deposits in the superheaters of a 220 t/h biomass-fired CFB boiler were studied, including the platen (PS), the high-temperature (HTS), the upper and the lower low-temperature superheaters (LTS). The results showed that the deposits in the PSs and HTSs were thin (several millimeters) and compact, consisting of a yellow outer layer and snow-white inner layer near the tube surface. The deposits in the upper LTS appeared to be toughly sintered ceramic, while those in the lower LTS were composed of dispersive coarse ash particles with an unsintered surface. Detailed characterization of the cross-section and the initial layers in the deposits revealed that the dominating compositions in both the PSs and the HTSs were Cl and K (approximately 70%) in the form of KCl. Interestingly, the cross-section of the deposition in the upper LTS exhibited a unique lamellar structure with a major composition of Ca and S. The contents of Ca and Si increased from approximately 10% to approximately 60% in the deposits from the high temperature surfaces to the low temperature ones. It was concluded that the vaporized mineral matter such as KCl played the most important role in the deposition progress in the PS and the HTS. In addition, although the condensation of KCl in the LTSs also happened, the deposition of ash particles played a more important role.     

Experimental Study on an On—Line Measurement of High Temperature Circulating Ash Flux in a Circulating Fluidized Bed Boiler

A new kind of measuring method that may be used to measure high temperature circulating solid particles flux in a circulating fluidized bed boiler is studied in this paper. The measuring method is founded on the principle of thermal equilibrium. A series of cold tests and hot tests were carried to optimize the structure and collocation of water-cooling tubes and showed that the method had the advantage of simple, accurate, reliable and good applicability for on-line usage in a circulating fluidized bed boiler.     

燃用石油焦和煤添加脱硫剂循环流化床锅炉热效率计算

论述了循环流化床锅炉燃用石油焦和煤添加石灰石时对锅炉热效率计算的影响．通过分析循环流化床锅炉燃用石油焦和煤混合燃料添加脱硫剂时的物料平衡和灰平衡。得出采用国标GB10184-88《电站锅炉性能试验规程》计算锅炉热效率时，要对热量、烟气量和灰量进行修正。结合一台220t／h CFB锅炉实例，计算出实际测试工况下的热效率为89．5％。     

循环流化床锅炉排渣分选装置的冷态试验研究

在一个可视化冷态试验台上对新型排渣分选装置的气固流动特性进行了试验研究,试验结果表明：分选室和主床同时运行时,主床和分选室之间存在合理的压力分布以形成“主床-分选室-主床”的颗粒循环运动;初始床料特性对分选室分选效果有一定的影响;分选室分选效果随着流化风速比ξ的增大而变好。     

Research on Marine Boiler＇s Pressurized Combustion and Heat Transfer

The effect of pressure on combustion and heat transfer is analyzed. The research is based on the basic combustion and heat transfer theorem. A correction for the heat calculation method for pressurized furnace is made on the basis of the normal pressure case. The correction takes the effect of pressurizing into account. The results show that the correction is reasonable and the method is applicable to combustion and heat transfer of the marine supercharged boiler.     

影响循环流化床锅炉燃烧效率的因素分析及改善措施

循环流化床锅炉具有高效、低污染、煤种适应性广等优点，在我国得到大力发展。但目前存在一个较为普遍的问题：飞灰含碳量高，锅炉燃烧效率达不到设计值。在对实例进行分析的基础上，探讨了煤的热值及煤的粒径、燃烧室特点、循环系统运行状况对锅炉燃烧效率的影响。提出了维持锅炉稳定燃烧，降低飞灰含碳量，提高燃烧效率的一些措施，在实践中证明是行之有效的。     

Effect of circulating ash from CFB boilers on NO and N2O emission

NO and N₂O emissions from circulating fluidized bed (CFB) boilers are determined by their formation and destruction rates in the furnace. The effect of circulating ash from a CFB boiler on NO and N₂O emissions were investigated in a laboratory-scale fluidized bed reactor. The results show that the residue char in circulating ash and the CO generated from the char play an important role in NO reduction and N₂O formation; however, active components of circulating ash such as CaO, Fe₂O₃ accelerate the decomposition of N₂O. Experiment was also conducted on a 75 t/h CFB boiler fueled with the mixture of anthracite and biomass. The lower residue carbon content of circulating ash in this experiment is lower; therefore, the reacting rate of NO deoxidize is limited. This result verified the conclusion of laboratory research.     

越南高岸CFB锅炉飞灰含碳量高的分析与对策

对越南高岸电厂的循环流化床锅炉进行了概述。并对自运行以来出现的飞灰含碳高的问题进行了分析,随后提出了解决的办法和优化、改进的目标及措施。通过现场的测试和运行,证明措施有效,效果非常明显。