更新时间:06-04 上传会员:小婷
分类:工业大学 论文字数:14592 需要金币:1000个
摘 要:在掌握燃烧和流态化理论的前提下,阅读相关文献,收集和综述循环流化床富氧燃烧的最新研究结论和发展趋势;了解钙基脱硫剂在循环流化床富氧燃烧条件下的脱硫机理和存在问题,探明其磨损机理;同时对循环流化床富氧气氛下石灰石脱硫的磨损进行试验研究,通过实验室规模下流化床燃烧系统中石灰石连续破碎测试实验装置、固体燃料燃烧试验系统等,了解影响固硫效果因素,如:石灰石粒度、流化床砂质种类、燃料的种类、燃料的粗细、燃烧温度、时间、空气表面流速等。
通过通过小型流化床实验,研究不同气氛下固硫剂磨损的差别,在常压循环流化床上,对钙基吸收剂的反应特性和磨损性能进行研究,考察反应时间、流化数、反应温度、颗粒粒径、煅烧温度对吸收剂磨损性能的影响以及吸收剂的磨损率变化情况。结果表明,反应温度对吸收剂磨损的影响最大,流化时间等影响较小,同时吸收剂粒径也是磨损性能变化的重大因素,吸收剂在煅烧过程中受热应力和CO2析出时的内压力作用是颗粒发生破碎的主要原因。
关键词:循环流化床富氧燃烧 钙基脱硫剂 破碎 磨损
Abstract:Under the premise of mastering theories of combustion and fluidization, read the relevant literature to collect the latest Attrition/fragmentation findings of limestone under simulated fluidized bed oxyfiring conditions. Understand the mechanism and search relative problems of calcium-based sorbent oxygen in circulating fluidized bed combustion and desulfurization. Meanwhile, take the reaserch of attrition and fragmentation of limestone during the fluidized bed (FB) oxyfuel combustion of sulfur-bearing fuels. With laboratory scale tests under the continuous limestone crushing test in fluidized bed combustion system or solid fuel combustion test systems, to know the relative factors which may affect limestone sulfation . such as Limestone particle size, fluidized bed sand type, fuel type, fuel physical size, combustion temperature, combustion time, surface air flow rate and etc.
Take the study on the difference of limestone attrition and fragmentation under different atmosphere with laboratory scale CFB oxyfuel tests. The effects of reaction time, fluidization number, particle size, calcination temperature on the sorbent attrition were investigated and know the changes of sorbent attrition rate. The results show that reaction temperature presents the greatest effect on sorbent attrition while the fluidization number and reaction time affect less. Otherwise, the particle size is important factor. The thermal shock and internal pressure due to CO2 releasing during the calcination were the main cause for the sorbent attriton.
Keywords: oxygen circulating fluidized bed combustion; calcium-based sorbent ;attrition;fragmentation