75t/h生物质循环流化床锅炉风帽沉积特性研究  

Deposition performance of air nozzles in a 75t/h biomass fired circulating fluidized bed boiler

作　　者：苏余宁 伍征团 余春江[2] 

机构地区：[1]广东粤电湛江生物质发电有限公司,广东湛江524300 [2]浙江大学能源清洁利用国家重点实验室,浙江杭州310027

出　　处：《热力发电》2014年第12期77-81,共5页Thermal Power Generation

基　　金：国家国际科技合作项目(2011DFA61060);国家科技支撑计划项目(2012BAA09B01)

摘　　要：某生物质循环流化床(CFB)锅炉运行中发现风帽表面出现沉积,采用多种方法对该类沉积进行了分析检测,研究发现其具有典型的分层结构。SEM和EDS以及XRD分析表明:不同层之间的元素组成是类似的,K、Na、Cl是构成沉积的主要元素,KCl和NaCl等碱金属盐类是沉积的主要成分;气相碱金属盐类在风帽表面冷凝是初始沉积形成的主要方式,而局部高温是沉积发展的重要因素;保证流化质量,降低燃料中杂质可以抑制风帽表面沉积的形成。Deposition occurred on surface of air nozzles in a biomass-fired circulating fluidized bed （CFB） boiler.Several measurement methods were applied to identify the compositions.Visual inspection shows the deposition has a typical layered structure.Detailed study was carried out by analyzing the sample via SEM （Scanning Electron Microscope）,EDS （Energy Dispersive Spectrometer）and XRD （X-Ray Diffraction）.It founds each layer of the deposition has similar elemental composition and K,Na,Cl are the main elements constituting the deposition.From the viewpoint of chemical compounds,alkali metal salts like KCl and NaCl are the main components.Condensation of alkali metal salts in gas phase on nozzle surface was con-sidered to be the major way by which the initial deposit formed,while the local high temperature was an important factor in the development of the deposit.Therefore,decreasing the heavy impurities from fuel and keeping high quality fluidization are effective to control the deposition formation on air nozzles.

关 键 词：生物质 CFB锅炉 风帽 沉积 碱金属 高温腐蚀 

分 类 号：TK224.9[动力工程及工程热物理—动力机械及工程]