共查询到17条相似文献,搜索用时 109 毫秒
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循环流化床锅炉的原理与设计 总被引:5,自引:0,他引:5
根据循环流化床的原理和作者多年来的实践,分析了目前国内循环流化床锅炉存在的主要问题。指出:灰平衡是分析固体不完全燃烧热损失的基础,也是计算锅炉热平衡和热效率的关键数据之一。一台循环流化床锅炉设计和运行的成功取决于炉膛、分离器和回料器的设计。鉴于目前国内循环流化床锅炉中各种新型分离器工作现状,很有必要对采用旋风分离器的问题重新认识。此外,还对回料器、对流受热面的设计等,发表了看法。由于环保条例对锅炉和燃烧设备的排放作了限制,燃烧无烟煤循环流化床锅炉要达到SOx等排放标准还须深入研究。 相似文献
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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。 相似文献
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Zhou Yi-gong 《锅炉技术》1998,(4)
目前,国内的循环流化床锅炉存在不少问题,就性能问题而言,主要是两大问题,一是不能定量地确定循环倍率,导致燃烧性能的计算不准确,二是不正确的灰平衡计算导致传热性能的计算不准确。所以,正确地确定循环流化床锅炉的循环倍率和灰平衡计算方法不仅是必需的,而且是迫切的。本文从灰平衡的基本要素出发,对循环倍率和农平衡的计算方法进行探讨. 相似文献
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本文介绍了DL/T964-2005《循环流化床锅炉性能试验规程》中对循环流化床锅炉做热平衡计算时q5、q6、q7的取用方法。 相似文献
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循环流化床锅炉中灰循环倍率与燃烧产物热平衡方程式 总被引:1,自引:1,他引:1
循环流化床锅炉在炉膛、分离器和回料器组成的灰循环系统中 ,存在大量的循环灰量。它是载热体 ,从炉膛吸入或放出热量。虽然循环灰温降不大 ,然而循环灰量却极大 ,严重影响燃烧产物的热平衡。在循环流化床锅炉热力计算时 ,必须加以考虑 相似文献
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A study of the heat transfer about the heating surface of three commercial 300 MWe CFB boilers was conducted in this work. The heat transfer coefficients of the platen heating surface, the external heat exchanger (EHE) and cyclone separator were calculated according to the relative operation data at different boiler loads. Moreover, the heat transfer coefficient of the waterwall was calculated by heat balance of the hot circuit of the CFB boiler. With the boiler capacity increasing, the heat transfer coefficients of these heating surface increases, and the heat transfer coefficient of the water wall is higher than that of the platen heating surface. The heat transfer coefficient of the EHE is the highest in high boiler load, the heat transfer coefficient of the cyclone separator is the lowest. Because the fired coal is different from the design coal in No.1 boiler, the ash content of the fired coal is much lower than that of the design coal. The heat transfer coefficients which calculated with the operation data are lower than the previous design value and that is the reason why the bed temperature is rather high during the boiler operation in No.1 boiler. 相似文献
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循环流化床动态灰平衡计算方法 总被引:2,自引:0,他引:2
本文建立了以煤燃烧成灰为床料的循环流化床总体质量平衡数学模型。它采用将固体颗粒划分为若干个直径档的方法来描述宽筛分特性;尽可能全面地考虑了进出流化床系统的物质流,以增强模型的通用性。由于考虑了给风流量同流化床压降间的耦合关系,并建立了诸多操作量和部件特性与流化床运行参数间的动态作用关系,使得本模型能够更真实、全面地模拟流化床的实际运行情况。通过试验数据,模型得到部分验证。 相似文献
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In the present work, the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes (38mm-O.D.) in a commercial circulating fluidized bed (CFB) boiler. Heat transfer behavior in a 1296t/h supercritical CFB furnace has been analyzed for Geldart B particle with Sauter mean diameter of 0.219 and 0.246mm. The heat transfer experiments were conducted for the active heat transfer surface in the form of membrane tube with a longitudinal fin at the tube crest under the normal operating conditions of CFB boiler. A heat transfer analysis of CFB boiler with detailed consideration of the bed-to-wall heat transfer coefficient and the contribution of heat transfer mechanisms inside furnace chamber were investigated using mechanistic heat transfer model based on cluster renewal approach. The predicted values of heat transfer coefficient are compared with empirical correlation for CFB units in large-scale. 相似文献